Question 1

Are MicroCare Products Approved for Use in Clean Rooms?

Accepted Answer

Clean room solvents and cleaning fluids are often required to meet clean room standards. As for using MicroCare fluids in a clean room, it depends on the “class” or cleanliness standard of the clean room. There is no problem with the purity of the liquid; it’s fine. It’s the packaging that determines the use.

A Class 10,000 clean room is the norm for many industrial applications. As such, aerosols and pump sprays generally would be fine there.
Class 1000 clean rooms normally do not permit aerosol and pump spray products because of the droplets they put into the air. So, the customer would use the cleaner in bulk (unpressurized) packaging and pour the liquid into bottles and jars. This is one of the reasons MicroCare offers our products in pails.
Class 100 clean rooms require positive air pressure, air locks, complete covering of the body with face masks, etc. Therefore, anything put into the clean room must come with clean room packaging. This is basically a double-pack: an outer package, for shipping and handling, that is removed and then the product is put into an airlock, and opened on the other side, at which time the second packaging is opened or removed. MicroCare cleaners are not packaged in this manner.

So, it depends upon the specification for the clean room.

Question 2

How Do I Measure PCB Cleaning Results?

Accepted Answer

There are four ways to check for PCB cleanliness:

The first is a simple visual inspection – if there are no visible flux materials and no white residues, most people just call it “clean enough.” Not very sophisticated, but it works.

A less precise but faster measurement of cleanliness is ionograph testing. This also is called “ROSE” or Omegameter testing. This is the least sensitive of cleanliness measurement techniques. They do not detect the weak organic acids (WOA) residues left by many no-clean fluxes. This process requires the board to be immersed in a bath of deionized water for 5 minutes or so. After the water has had a few moments to circulate around the components, the water is tested for ionic contamination. Since the DI water will dissolve ionics from the boards, any change in resistivity of the water would indicate the relative dirtiness or cleanliness of the board. The Omegameter 600SMD probably is the industry standard for ionic testing. The system provides an accurate, repeatable and rapid method for determining cleanliness and complies with industrial specifications including MIL-STD-2000A, IPC-TM-650 and ANSI/J-STD-001B. In general, these tests are best used for monitoring process equipment, for bare PCB cleanliness testing and for finding halide residues.

Next, and at the other end of the complexity scale, is Surface Insulation Resistance (SIR) testing. A full SIR test takes 28 days, a big machine and serious system calibration; one of the industry leaders is Thermotron. Most users simply farm out the test to a research lab. The result of an SIR test is a measure of the resistance of electrical flow across the traces on a PCB caused by conductive contamination, such as the ionics from fluxes. High resistance is good and means the board is clean.

The best practice is to assess and control contamination through ion chromatography (IC) testing, the “gold standard.” Ion Chromatography is the only test that finds and quantifies WOAs. Because of the expense, very few PCB manufacturers define quality standards based based on IC results.

The number one cause of complaints about PCB cleaning are white residues on the board. These usually are salt crystals, residues of imperfect cleaning.

Question 3

Which Cleaner Is the Best to Remove HumiSeal 1B31 (Acrylic Conformal Coating)?

Accepted Answer

We are using MicroCare DC1 for lacquer removal, Humiseal 1B31. It works OK, but not perfect, and we do quite a few each day. Is there anything better?

(Editor's note: 'Lacquer' is a term often used in Europe to describe conformal coatings.)

We're a little surprised the No-Clean Flux Remover - VeriClean™ (#MCC-DC1) works at all. This cleaner is siloxane-based and is the best choice for silicone conformal coatings. Humiseal 1B31 is an acrylic. According to the Humiseal product spec sheet, “HumiSeal 1B31 is a fast air drying, single component, acrylic coating that provides excellent moisture and environmental protection for printed circuit assemblies.” Acrylics are best removed with the Lead-Free Flux Remover - PowerClean™ (#MCC-PW210A) or the Heavy Duty Flux Remover - SuprClean™ (#MCC-SPR) both of which are fast-drying, nonflammable, high Kb flux removers. You'll find them much better choices for cleaning the thin, hard acrylic coatings. Try one of them and you will see the results are much faster and better.

Be advised the one type of confiormal coating we CAN’T remove are the “thermoset” materials, which take a heat-cure process, such as epoxies and Paralene.

SuprClean™ is a powerful, HFC-based fluid used for traditional (RMA) fluxes, solder pastes, plus oils, grease, some inks and acrylic conformal coatings.

Question 4

How Can I Cost-Justify the Trigger Grip System?

Accepted Answer

It’s a funny thing — MicroCare’s biggest competitor is not some other aerosol company. Our biggest competition is cheap alcohol in a small bottle. “Dip-and-brush” cleaning is cheap to buy, but more expensive to use. In our opinion, dip-and-brush cleaning at the benchtop is an expensive way to get poor results.

Remember that alcohol is hygroscopic, which means it absorbs water from the air. This dilutes it, and weakens its ability to clean.

Alcohol also is often diluted with water by 20% or more, simply to keep costs down. This dramatically reduces its cleaning strength. So using a bad process with a weak cleaner leads to expensive cleaning.

If people want the lowest total cost per part cleaned then everybody should use the TriggerGrip™ dispensing system. With each TriggerGrip™ tool customers will get better, faster, more reliable cleaning at a lower cost per-part- cleaned.

The High Costs of Dip-and-Brush Cleaning

You see, its not the cost of the solvent that is the issue here — it’s the cost of wasted time. The TriggerGrip™ dispensing system forces techs to use all four steps of the cleaning process — wet, scrub, rinse and dry. Because the techs use all four steps, the results are better, safer, faster and less expensive. This results in substantial savings.

For example, MicroCare products typically cost $0.50 – $1.00 per day to use. With a TriggerGrip™ dispenser on their workbench, MicroCare helps the tech do more cleaning in less time. This time-saving is typically about 30 minutes per day per technician. So if the company has 15 techs in the rework area, MicroCare can save 30 minutes times 15 people — that’s about 8 hours per day. So the company gets one technician work-day for free, if they use MicroCare.

Here’s another way to figure it out: How many pieces of rework does each tech do in a day? What is the value of that rework? Usually it sounds something like this: “Well, our techs typically rework 60-80 pieces per day, and each box that leaves the factory is worth $50 profit to the company.” In an eight-hour day, that works out to roughly ten pieces per hour, or $500 gross profit per technician per hour. Now do the math. The TriggerGrip™ system saves 30 minutes per tech per day, which is 5 pieces, at $50 each piece, it produces a total of $250 additional profit per tech per day. With 15 techs, the TriggerGrip™ dispensing system will save enough time to rework $3,750 more products and produce more profit each day.

Or, putting it another way, NOT using the TriggerGrip™ dispensing system burdens the company with $3,750 worth of extra cleaning costs every single day.

To put it still another way: buying cheap alcohol may cost you 50¢ per benchtop per day and the TriggerGrip™ dispensing system might cost you $1 per day. But because dip-and-brush cleaning is slow and the quality is poor, your techs waste a lot of time doing it. This lost productivity costs you hundreds of times more than the money you save with cheap solvent.

So it’s not the cost of the can of solvent — it’s the lost profits, the hidden costs, and the lost productivity of your technicians that make MicroCare a great choice for benchtop cleaning.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 5

How Do I Dispose Empty Aerosol Cans and Pump Spray Bottles?

Accepted Answer

Safe disposal of cleaning fluids is important. Aerosol cans, pump sprays and bulk packages usually are considered hazardous waste in most communities. That’s important because these packages usually contain small amounts of residual solvents which could contaminate ground water. It’s important to keep those contaminants out of the landfills. So contact your local waste disposal expert and find our what’s right in your community and with the regulations under which you operate.

Guaranteed to Empty Completely

That being said, MicroCare has a unique advantage. MicroCare guarantees that our cans will empty completely when you use them with the TriggerGrip™ dispensing system AND the Bench Mounting Kit. To be precise, we guarantee the cans will contain less than 2% of their original weight of solvent and may be classified as “DOT empty.” In this mode, the disposal problems can be greatly reduced. Because only MicroCare has the Trigger Grip system, only MicroCare can offer you this cost savings.

In addition, MicroCare uses liquid propellants to help ensure that users dispense the full contents of each MicroCare aerosol can. This leads to three possible scenarios from a disposal perspective:

Under normal use the liquid propellant ensures all MicroCare aerosol cans are fully consumed during use and are “empty” as defined by 40 CFR 261.7b(1) and/or 40 CFR 261.7b(2). An “empty” aerosol can is not subject to hazardous waste regulation and the empty container should be recycled as scrap metal.
If during use, a user finds they are unable to fully dispense the contents of a MicroCare brand aerosol can, it may be returned to MicroCare under a MicroCare issued Returned Materials Authorization (RMA). Products returned to MicroCare as defective under an RMA are given a full quality review to determine root-cause of the quality issue, and ultimate disposition is within compliance with applicable regulations. Under such circumstances, MicroCare at its option, may either offer customer credit or replace the defective can.
If for any reason you should decide to dispose a MicroCare aerosol can that is either unused (full) or partially used, that full or partially filled aerosol can is declared as waste. The full or partially filled waste aerosol container may be identified for disposal as a universal waste under new EPA rules.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 6

What’s the Best Way to Dry a PCB on the Benchtop?

Accepted Answer

There are four steps to successfully cleaning PCBs (printed circuit boards). Wet, scrub, rinse and dry. The wet, scrub and rinse operations are obvious. Wet the board with a pure cleaning fluid. Scrub it using a good quality scrubbing brush. Then rinse it off with more clean fluid. However, the dry step is often overlooked or in some instances, completely left out of the PCB cleaning plan.

For reliable performance, circuit boards must not only be clean, they must be dry in order to function properly. Leftover moisture on a PCB surface can lead to a host of problems including corrosion, electrochemical migration, delamination, dendrite growth, pin holes and blow holes and adhesion problems with conformal coatings later in production. Modern PCBs often have bottom termination components like land grid arrays and QFN (quad-flat no-leads) with very tight standoff heights. Moisture can get trapped under these components, making drying even more complicated.

There are different ways to dry to ensure printed circuit boards are not only clean, but also dry for optimum reliability and performance.

Capture the excess spray of cleaning fluid on a circuit board or gently pushing the wipe under low-surface mounted components, wipes are a quick and effective way to dry the PCB without leaving lint or fuzz behind. There are many factors to consider when selecting a lint-free drying wipe including absorbency, material and packaging.

Manual Cleaning & Drying with Wipes and Dusters

One of the most commonly used methods technicians use to dry PCBs during benchtop cleaning is a simple lint-free wipe. Whether using it to capture the excess spray of cleaning fluid on a circuit board or gently pushing the wipe under low-surface mounted components, wipes are a quick and effective way to dry the PCB without leaving lint or fuzz behind. There are many factors to consider when selecting a lint-free drying wipe including absorbency, material and packaging.

The most important factor when choosing a drying wipe is the ability of the wipe to absorb the type of moisture encountered. For example, some wipes will absorb cleaning fluids, but they will not absorb water. The key is to match the type of wipe absorbency to the contamination to be removed.

The material makeup or the type of fiber used to make the wipe is also important. Nonwoven wipes, since they are made without glues or binders, don’t leave residue on the surface being cleaned, resulting in a cleaner PCB. Another way to limit re-contamination to the PCB is to choose pre-washed wipes or wipes with finished or heat-sealed edges. This eliminates loose fibers and dust, ultimately leaving the printed circuit board cleaner.

For some benchtop post reflow (rework) assembly a good drying method is to use a dust remover. A quick blast of from a duster can be effective at blowing trapped moisture from underneath larger components that a wipe alone might not reach. The dust remover can be targeted to a very small area on the PCB and works extremely well in getting into and under intricate and hard-to-reach nooks and crannies on the circuit board. Using a duster in combination with a wipe doubles the drying power and prevents the fluid from being pushed back onto on the board and spreading contaminant around.

When selecting a duster to use for a drying application, safety is key. Inexpensive canned air is readily available from a number of retail outlets. However, many of these formulations may pose a hazard due to their high flammability ratings. A safer alternative is to select a dust remover that is made with nonflammable gas. A 360° type of dust remover also adds drying convenience since the can operates at any angle, even upside down, allowing operators the flexibility to quickly dry very complex or intricate PCBs. Using the duster may take a little bit of practice, but once the operator understands the velocity of the high-purity gas, the moisture can be blown away quickly and efficiently with no residue left behind.

Question 7

How Do PCB Cleaning Pens Work?

Accepted Answer

PCB cleaning pens are big time savers and incredibly convenient.

For years, MicroCare has sold a very popular product called the TidyPen™. It’s very effective at removing sticky labels, tapes and adhesives from PCBs.

Using that same pocket-sized pen format, MicroCare developed a line of PCB cleaning pens for pin-point cleaning water soluble, RMA and no clean fluxes.

So, now if you just want to do a tiny little touch-up right on one small spot of a board or around a chip, you can do it very quickly, easily and with no mess. Simply tap the pen tip on the PCB and “erase” the contamination on the board. They are ideal for improving the performance and aesthetics of any complex or tightly-packed PCBs.

Types of PCB Cleaning Pens include:

Question 8

Any NSN Numbers Assigned to MicroCare Cleaning Products?

Accepted Answer

MicroCare has many 'National Stock Numbers' (NSN numbers) assigned to the MicroCare cleaning products. These are used by the U.S. government and most NATO countries to specify approved products for different tasks, including PCB cleaning. You can find these NSN numbers on the product specs, on the web page for each product and on the product labels. For convenience, the complete list of NSN numbers of currently active products is included here: MicroCare Current NSN Numbers

Question 9

Which MicroCare Aerosol Cleaner is the Strongest?

Accepted Answer

Cleaning strength is measured by the Kari-Butanol rating of the solvent, shown on MicroCare product specifications as the “Kb number.” (Some competitors do not offer Kb ratings on their products, which we find odd.) A rating of 20 or so is mild while anything over 70 is a aggressive solvent that will probably not be plastic-safe. Our strongest solvent, the Lead-Free Flux Remover – PowerClean™, has a Kb value over 100.

The Polar Flux Remover can be used with the TriggerGrip cleaning tool to deliver cleaner PCBs and lower cost.

All that being said, if you need real muscle for age-hardened rosin fluxes or maybe some nasty conformal coatings, try these: Lead-Free Flux Remover – PowerClean™ (#MCC-PW2) or Heavy Duty Flux Remover – SuprClean™ (#MCC-SPR) for fast-drying choices, and the Uncured Epoxy Remover – ExPoxy™ (#MCC-EPX) for a slower-drying choice. If the environment permits flammable cleaning fluids, a good choice is the Polar Flux Remover (#MCC-PFR). All are superior choices for most cleaning applications. If you are cleaning residues that may be soluble in water, go with the money-saving Reflow Oven Cleaner (#MCC-ROC).

Here are the details…

Heavy Duty Flux Remover – SuprClean™ was first introduced late in 1998. Formulated specifically for high-powered defluxing, it cleans great, dries fast, has almost no aroma, and is nonflammable. It is a great choice for cleaning traditional fluxes, pastes, oils, grease and some inks. Ozone-safe, easy-to-use SuprClean™ rocks with cleaning power. It knows no bounds! TriggerGrip™ compatible.
Lead-Free Flux Remover – PowerClean™ is the strongest of the nonflammable, fast-drying solvents. Most importantly, it works great on the high-temperature lead-free solders and pastes and easily eliminates the white residues that often occur when cleaning those materials. It’s the least expensive product in it’s class. It also can be used with the TriggerGrip™ system.
The Uncured Epoxy Remover is a combination defluxer, degreaser and stencil cleaner. Based on a hydrocarbons it’s relatively slow-drying and about as strong as the old 1,1,1-TCA (especially on grease, oils and other heavy contamination). This means it is ideal when you are cleaning more than just circuit boards — such as mechanical parts, housings and work benches. Overall, it cleans well, is very versatile and highly affordable, with superior toxicity ratings and less expensive than other choices.
The Reflow Oven Cleaner is a powerful, water-based cleaner. It is an aggressive, nonflammable, slow-drying solvent engineered specifically to remove baked-on fluxes from inside wave solder machines and reflow ovens. This cleaner dissolves conveyor-clogging flux residues inside the ovens. The chemical is safe on pallets, baffles, heating elements, clamps, chains, pulleys, drive gears and housings. Rinsing is never required. The refillable pump spray makes cleaning easy and fast.

One final warning: all of these products are very, very aggressive cleaners. Before putting them into wide-spread use, you should test them thoroughly, especially on soft plastics, gaskets, insulation and rubber. While they will not damage today’s tough SMT components, they can easily chew up older passive components, housings and mechanical parts (e.g., platens, drive wheels) coming in for repair.

Question 10

How Do I Clean Fiber Optic Components on PCB Circuit Cards?

Accepted Answer

Using a fiber smaller than human hair, digital fiber optic networks have transformed our world. Today’s highly mobile world, with email anywhere, video on-demand and endless streaming video all is a direct result of powerful, reliable fiber optic networks. But amazingly, the signal carried by the fiber is astoundingly fragile. So cleaning connectors and end-faces is not merely important; it is critical to the speed and the long-term reliability of any network. If fiber end-faces and connectors are not cleaned properly, the network will not run at its best, guaranteed.

Almost every fiber network is connected at each end to printed circuit boards using fiber optic transceivers. These are tiny devices mounted on the PCB that takes the optical signal and converts it to an electrical pulse. Manufacturers know that the boards need to be clean to operate successfully, preventing signal noise, dendrite growth and corrosion. But the optical end of the fiber optic transceiver can’t be cleaned with a the same products used on the PCB itself; that will not nearly be clean enough.

Here are the tools needed for successful end-face cleaning:

Wipes: The wipes need to be lint-free prevent leaving glue residue or lint on the fiber end faces.
Cleaning Sticks: Avoid foam swabs since they tend to hold the contamination and deposit them back onto the surfaces being cleaned. Opt for ultra-clean synthetic polymer tipped stick instead.
Fluids. Don’t use alcohol since it is difficult to keep clean and uncontaminated during day-to-day operations. For the very best results, technicians should be provided cleaning fluids that are ultra-pure, water-free, not refillable, and have a fast rate of evaporation. These characteristics will ensure that cleaning fluid will not leave excessive moisture or residues on the fiber.

One last thing: Never re-use any stick or wipe. Contamination can easily be transferred from one end-face to the next by reusing these tools.

Question 11

What's a TriggerGrip™ and How Does It Help Me?

Accepted Answer

The TriggerGrip™ cleaning system is an inexpensive tool that is used to clean printed circuit boards at the benchtop. Based on decades of satisfied customers, MicroCare can justifiably claim this is the single best way to clean PCBs during rework and repair. It helps companies get their boards cleaner, faster, more safely and at lower cost than any other method or product.

The TriggerGrip™ tool includes four parts: the TriggerGrip™ dispenser, the Bench Mounting Kit, an aerosol can of your favorite cleaning solvent, and a brush or two that fits on to the TriggerGrip™.

The big advantage of the TriggerGrip™ is that the normal cleaning power of the solvent is amplified by the mechanical scrubbing action of the brush. The system also makes it easy to rinse contamination off the PCB and, as we like to say at MicroCare, if you can't rinse, you can't clean. It's that simple.

This web site contains dozens of FAQs, videos and white papers that document the savings and process improvements available from using the TriggerGrip™ tool. Check out the related FAQs and other links, below:

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 12

What's the Best Way to Clean PCBs at the Benchtop?

Accepted Answer

Almost everybody uses the dip-and-brush method to clean circuit boards during rework and repair. But this process doesn’t work very well.

Other companies suggest you should use high-pressure aerosols and blast the contamination off the board. Which will work fine, if you don’t mind buying lots of aerosol cans.

At MicroCare, we think the best way to clean PCBs is with the TriggerGrip™ cleaning system. We invented it after watching people try to clean PCBs using the older processes. The reason the TriggerGrip™ system works great is because it forces the benchtop techs to use the four-step cleaning process: Wet, Scrub, Rinse and Dry.

When you think about it, everything gets cleaned using these same four steps. Your car. The dishes in the sink. Your teeth. A baby in the bath, your hair in the shower in the morning, and so on.

So if everything is cleaned using wet-scrub-rinse-and-dry, why do we only use two steps (wet-scrub) when we try to clean circuit boards? Remember: if you can’t rinse you can’t clean. It simply doesn’t work.

The TriggerGrip™ system allows you to obtain great cleaning quickly, easily and without a lot of chemical waste. Get one today!

Messy aerosol sprays volatilize the cleaning fluid, exposing workers to fumes. The excess fluid also can puddle below the cleaning site, creating a flammability hazard if the solvent has flammable characteristics

Question 13

Is Dip-and-Brush Cleaning Good for Cleaning Circuit Boards?

Accepted Answer

Why do engineers like dip-and-brush so much? Because they THINK it works fine and it appears to be inexpensive. Many don't know there are better alternatives to IPA and a brush. In fact, there are three things wrong with dip-and-brush cleaning: the process, the tool and the solvent. Let's take a look...

If You Can't Rinse, You Can't Clean

First, dip-and-brush cleaning isn't sufficient with today's modern electronics. In general, everything gets cleaned using the same four steps: Wet, Scrub, Rinse and Dry. But since dip-and-brush method doesn't enable techs to rinse the board, the contamination stays on the board. The techs can move it around, but most of the contamination stays on the PCB. As we like to say, techs can MOVE the residues but cannot REMOVE it. So they waste a lot of time, which is far more expensive than a TriggerGrip™ cleaning tool.

The Brush and the Bottle

It's very hard to get clean PCBs when you're using a dirty brush and dirty solvent. If the brush was cleaned after each use this might be an acceptable process. if the solvent was changed frequenrly and the bottle completely cleaned, that might be acceptable. But in truth, nobody does that. So the flux residues get re-deposited on the PCB. In December 2007, there was a very interesting technical note in Circuits Assembly Magazine by Mr. Terry Munson who bills himself as 'The Process Doctor.' Mr. Munson measured the contamination left on the boards after dip-and-brush cleaning using SIR testing, the most advanced form of board cleanliness testing. He concluded that rarely, if ever, would dip-and-brush cleaning achieve satisfactory results. It's simple. Most techs would love to have a better PCB cleaning tool, if one was available, and the Trigger Grip™ is the benchtop cleaning tool your techs need.

The Problems with IPA

Now, let's talk about the solvent. Alcohol has problem in general: it's flammable, it's hygroscopic, and it's smelly, and it's a weak cleaner. Technicians try to make IPA work. But they don't like it. They spend a lot of time (and your money) trying to clean with a old-fashioned solvent and an inappropriate process. No wonder they get inconsistent results. Most techs care about the following characteristics of their solvent, in this order of importance:

Smell. No smell is better than a nice smell, which is better than a bad one
Evaporation Speed. The faster the better
Cleaning Strength. If it cleans fast and easily, that makes their job easier
Safety. Nonflammable is better than flammable

Our recommendation: give everybody a can of the General Purpose Flux Remover (#MCC-FRC), a TriggerGrip™ cleaning tool and a Bench Mounting Kit. It's an inexpensive little system that works great, is priced right and solves all of the technician's worries.

Question 14

How Do I Use the TriggerGrip™ System?

Accepted Answer

Companies around the globe have selected the TriggerGrip™ cleaning system for their benchtop cleaning. Here are the simple steps that will produce great results when cleaning with a TriggerGrip™ system:

Wet. First, hold the PCB at a slight angle, supporting it on a workbench or tabletop. Position the area to be cleaned on the lowest side. Spray a small amount of cleaning fluid on to the board, wetting the surface.
Scrub. Gently scrub the board with the TriggerGrip™ system. A little squirt every now and then will help loosen the grime; there is no need to spray continuously. Many techs customize the TriggerGrip™ system with different brushes or syringes to clean more quickly with less solvent, or use their lead trimmers to shape the brushes to get into hard-to-reach corners.
Rinse. Once the contamination is dissolved, briefly spray and rinse the board. Rinsing off on to a lint-free wipes shows the flux residues clearly, helping techs to be sure they have cleaned properly.
Dry. After rinsing, gently shake the board to dry it quickly. For slow-drying solvents, expedite drying with a gentle squirt of compressed air or by absorbing the liquid into a lint-free wipe (for example, the popular #MCC-W66 wipe).

If any step is skipped, the boards will not be cleaned in a speedy and cost-effective manner. For example, “dip-and-brush” cleaning skips the rinsing step leaving contamination on the board. Old-style aerosols are great at wetting and rinsing, but use too much solvent and may expose workers to hazardous fumes. That’s why customers appreciate the TriggerGrip™ cleaning system.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 15

How Long Will A TriggerGrip™ Last?

Accepted Answer

Fundamentally, you are asking about the value of the TriggerGrip™ system: will each tool last long enough to save me the money I spend to buy it? That’s a great question. And you’ll be pleased to know the TriggerGrip™ system will meet your expectations.

Each rugged, static-safe TriggerGrip™ dispenser (#MCC-ESD) should last years in normal use. A minimum life for those products in a normal production environment should be at least three years. You can make your TriggerGrip™ systems last longer by (a) using it in conjunction with the Bench Mounting Kit (#MCC-BK3), (b) not coiling the hose around the can at the end of the day for storage, and (c) keeping the hose from rubbing against sharp metal edges, such as are found on some workbenches.

The TriggerGrip™ brushes, by the way, last 3-4 months in normal use.

Proper training for your people also helps wonderfully. MicroCare offers a snappy, 7-minute training video that shows your team how to connect the TriggerGrip™ system, how to use the device, and then how to disconnect it safely. Again, just contact MicroCare and we’ll get you copies of the DVD for your training team.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 16

Why Does MicroCare Have So Many Different Benchtop Cleaning Choices?

Accepted Answer

That's a simple question with a complex answer. The fact is that customers want lots of choices and a wide array of options. PCBs are changing, too — the way we made electronics in the 1970s has nothing in common with the advanced microelectronics being sold today; it makes sense that cleaning would evolve as well. In addition, local rules are always changing — like the new F-gas rules in Europe and the demand for VOC-free cleaning in California. Lastly, the chemistries themselves are constantly evolving and improving: consider our new offers, the VOC-Free Flux Remover - UltraClean™ and the Universal Flux Remover, both of which offer chemistries simply not available years ago.

So, while cleaning experts at MicroCare are absolutely convinced that we could meet 90% of our customers' requirements with just three or four choices, we're here to provide what people really want, and they really want the most variety and versatilty they can get.

The favorite choices right now are:

Lead-Free Flux Remover - PowerClean™ for cleaning lead-free PCBs,
General Purpose Flux Remover for cleaning other PCBs,
The best-selling No-Clean Flux Remover - VeriClean™ for cleaning in areas where VOC restrictions are tight
Aqueous Stencil Cleaner for almost all other degreasing and cleaning applications.

Of course, you can't blame engineers who want to optimize their processes. We've seen engineers spend a lot of time evaluating very small differences between solvents. That's why we have so many choices. In fact, part of our service at MicroCare is to develop the new solvents and cleaners for tomorrow's applications. It's a burden we are pleased to shoulder.

The MicroCare family of cleaners the the electronics industry’s widest array of the most versatile cleaning choices. Whatever your application, MicroCare has an answer for the benchtop

Question 17

How Long Does a Can of MicroCare Cleaning Fluid Last?

Accepted Answer

The life span of an aerosol can being used on the benchtop varies by the amount of cleaning that is performed and the skill of the operator doing the cleaning. But — and this is important — the key is to let those operators use the TriggerGrip™ dispensing system. In general, the TriggerGrip™system will double or even triple the life of an aerosol can. This means in a normal manufacturing environment, where a old-fashioned high-pressure aerosol might last 2-3 days working days, a can of Lead-Free Flux Remover – PowerClean™ will last 5-6 days, No-Clean Flux Remover – VeriClean™ will last typically 8-10 working days, and a can of the slower-drying Alcohol-Enhanced Flux Remover – ProClean™ might last 15-20+ days.

In addiiton, to maximize can life and maximize savings, you should switch (whenever possible) to the slower-drying solvents. Since these fluids evaporate more slowly, operators have more time to work with the solvent, so consumption declines. Almost always, slower-drying fluids are flammable so there is a trade-off in economics and safety.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 18

How Long Does a Can of MicroCare Flux Remover Solvent Last?

Accepted Answer

The correct answer is, it depends on (a) what you are cleaning, (b) how much you are cleaning and (c) how well trained your people are.

If your people are using the TriggerGrip™ dispensing system it should double or even triple the life of an aerosol can. This means in a normal manufacturing environment, where a traditional high-pressure aerosol might last 2-3 days working days, a can of the fast-drying solvents the Lead-Free Flux Remover — PowerClean™ (#MCC-PW210A) or the No-Clean Flux Remover — VeriClean™ (#MCC-DC1) will last 5-10 working days. In the same scenario, a can of the medium-drying speed product, Alcohol-Enhanced Flux Remover–ProClean™ (#MCC-PRO) might last 15 days and a can of slow-drying Citrus-Based Flux Remover (#MCC-EC7M) might last 20+ days.

Companies that use the TriggerGrip™ system also will find that the aerosol cans are guaranteed to empty completely, a promise no other company makes.

In addition, to maximize can life and maximize savings use slower-drying solvents. Since they evaporate more slowly, operators have more time to work with the solvent, so consumption declines.

It’s not the cost-per-can that really matters, it’s the cost per-board-cleaned! Nothing cleans more affordably than the MicroCare TriggerGrip™ cleaning system.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 19

Which Cleaner Works Best on Lead-Free Fluxes and Pastes?

Accepted Answer

Lead-free fluxes and pastes are difficult to clean. They are soldered at higher temperatures and the residues become “cured” and hard to remove. You need real muscle for age-hardened lead-free fluxes, even no-clean lead-free products.

For best results, try Lead-Free Flux Remover – PowerClean™ (#MCC-PW2). This is the strongest of the nonflammable, fast-drying solvents because it contains a large proportion of the solvent “trans.” Most importantly, it works great on the high-temperature lead-free solders and pastes and easily eliminates the white residues that often occur when cleaning those materials. It’s the least expensive product in it’s class. For best results, use it with the TriggerGrip™ cleaning system.

For stencil cleaning, the Uncured Epoxy Remover — Expoxy™ (#MCC-EPX) is a combination defluxer, degreaser and stencil cleaner. Based on a hydrocarbons it’s relatively slow-drying and about as strong as the old 1,1,1-TCA (especially on grease, oils and other heavy contamination). This means it is ideal when you are cleaning more than just circuit boards — such as mechanical parts, housings and work benches. Overall, it cleans well, is very versatile and highly affordable, with superior toxicity ratings and is less expensive than other choices. This is most often used in presaturated wipes.

The Reflow Oven Cleaner (#MCC-ROC) is a powerful, water-based cleaner designed to remove uncured lead-free materials. It is an aggressive, nonflammable, slow-drying solvent engineered specifically to remove baked-on fluxes from inside wave solder machines and reflow ovens. This cleaner dissolves conveyor-clogging flux residues inside the ovens. The chemical is safe on pallets, baffles, heating elements, clamps, chains, pulleys, drive gears and housings. Rinsing is never required. The refillable pump spray makes cleaning easy and fast.

PowerClean™ is a super-strong, nonflammable, fast-drying solvent that prevents the formation of white residues on PCBs

Question 20

What's Best for Cleaning RMA Fluxes and Pastes?

Accepted Answer

Some PCB makers are using the dip-and-brush method to clean circuit boards during rework and repair. However this process doesn't allow you to easily rinse contamination off the PCBs after they are scrubbed.

Other companies use high-pressure aerosols to blast the contamination off the board, but that often wastes cleaning fluid due to overspray.

At MicroCare, we think the best way to clean PCBs is with the TriggerGrip™ cleaning system with a planet-friendly cleaning fluid. The TriggerGrip™ system allows you to obtain great cleaning quickly, easily and without a lot of chemical waste, even under tight-fitting BGA components.

For R, RA, RMA and SA fluxes and solder pastes, the best choices from MicroCare have high density, high Kb values, low surface tension and low viscosity. The best choices might be: the Heavy Duty Flux Remover — SuprClean™, the General Purpose Flux Remover and the Alcohol-Enhanced Flux Remover — ProClean™.

Messy aerosol sprays volatilize the cleaning fluid, exposing workers to fumes. The excess fluid also can puddle below the cleaning site, creating a flammability hazard if the solvent has flammable characteristics

Question 21

What's the Best Cleaner for 'No Clean' Solders and Pastes?

Accepted Answer

The No-Clean Flux Remover – VeriClean™ (#MCC-DC1) works great on “no clean” materials. However, a newer formulation from MicroCare — the VOC-Free Flux Remover – UltraClean™ (#MCC-VOC10A) — is an excellent choice and some users report the fast-drying, nonflammable General Purpose Flux Remover – Flux Remover C (#MCC-FRC) delivers good results as well.

The UltraClean™ products is a radically different cleaning formulation engineered exclusively by MicroCare. It is a highly effective circuit cleaner, offering superior results on “no-clean” fluxes and very good cleaning on rosin- and lead-free fluxes as well. This product also easily removes silicone conformal coatings and silicone glues. An excellent choice for defluxing circuit boards during rework and repair, this fast-drying fluid is the strongest cleaner on the market in its class (non-chlorinated, non-halogenated solvents).

VeriClean™ is another quick-drying cleaner with almost lower aroma than the UltraClean product; it’s widely used in areas where VOCs are a concern.

Lastly, the General Purpose Flux Remover C is an excellent choice. it is based on HFC solvents so it is nonflammable. It cleans great, is generally plastic safe, has a modest aroma, fast drying, and a very competitive price.

Special Note: If you are cleaning no-clean pastes from stencils or misprinted boards, the best choice is either the water-based Aqueous Stencil Cleaner (#MCC-BGA) or the solvent-based MultiTask™ Surface Cleaner Economy Wipes (#MCC-MLCW).

The number one cause of complaints about PCB cleaning are white residues on the board. These usually are salt crystals, residues of imperfect cleaning.

Question 22

Why Should I Clean 'No Clean' Fluxes and Pastes? Can I Just Skip the Cleaning and Save Some Money?

Accepted Answer

Why would anybody want to clean no-cleans? Well, it happens all the time. Cleaning delicate circuitry is easy with MicroCare solvents, even when no-clean fluxes are used. Probably most of the companies using the No-Clean Flux Remover - VeriClean™, the Alcohol-Enhanced Flux Remover - ProClean™ sales and almost all of our Lead-Free Flux Remover - PowerClean™ customers are using them on 'no clean' flux residues. An unofficial estimate from the sales team at MicroCare suggests that about 50% of our business now involves helping people clean 'no cleans'. Here's why...

The Ten Most Common Reasons to Clean Circuit Boards Made with 'No Clean' Fluxes and Pastes

Flux residues are not the only material being removed (ink, salts and solder balls, fingerprints)
Flux residues make visual QC inspections nearly impossible
Flux residues cause automated visual alignment systems to fail
Flux residues cause 'bed of nails' test systems to fail
Flux residues cannot be tolerated on high-voltage systems
Flux residues add noise on analog-to-digital conversion circuits
Flux residues make troubleshooting field repairs failures very difficult
Flux residues make R&D work, like troubleshooting new designs, difficult
Flux residues detract from the cosmetic appearance of the boards
Flux residues make conformal coatings fail

And what are all these people cleaning? Many are cleaning circuit boards during manufacturing, rework and repair. But even if the classical benchtop cleaning process is ignored, there's lots of cleaning to be done in today's electronic assembly facilities:

Ten Common Cleaning Jobs Found Even in 'No Clean' Production Environments

Stencil cleaning
Cleaning mis-printed boards
Pre-tinning of components requires activated fluxes
Equipment maintenance (reflow ovens, pallets, degreasing light oils from pick-and-place machines, test machines) on the production line
Incoming inspection from subcontractors
Removing labels, tapes and adhesives, such as bar codes or Kapton tape
Head cleaning on tape recorders, VCRs and disk drives
Removing dirt and grime from cabinets and housings
Cleaning products before they are repaired (warranty repairs, product returns)
Repairing products which have failed in the field.

It makes you think about the 'no clean' claims!

Question 23

Which Is the Mildest MicroCare Cleaner?

Accepted Answer

Companies seek mild cleaners for many reasons, but the most common issue is materials compatibility. Strong cleaners deliver great results and clean quickly, but may attack soft plastics, rubber, conformal coatings or remove inks. If this are a concern, then you need for a cleaner with a low Kb value that will not dissolve, craze or attack softer substrates. From MicroCare, the most popular circuit board cleaners that are milder and plastic-safe would be:

Among the maintenance cleaners, the milder choices are the Streak-Free Glass Cleaner. Lastly, the Universal Contact Cleaner is a fine nonflammable choice for rinsing insoluble particulate from components.

Question 24

Which Cleaner is Best at Removing Conformal Coatings?

Accepted Answer

Conformal coatings are challenging. First, they are designed to be very durable and hard to remove. Then, there are many, many different types of coatings, and many are old formulations which require old solvent which are no longer widely acceptable. Let’s take a look at some good choices for more common applications:

Silicone Coatings

Dow Corning and other companies produce very popular conformal coatings based on silicones. They offer great protection while being light, durable and easy to rework. Almost without exception, silicone coatings may be removed by either the VOC-Free Flux Remover — UltraClean™ or the No-Clean Flux Remover – VeriClean™. This product is based on siloxane technologies, so it is chemically very similar to most silicone conformal coatings. In one test with a large Texas computer manufacturer, No-Clean Flux Remover – VeriClean™ removed in two minutes a coating which had been taking 45 minutes to remove with more traditional solvents.

Acrylic Coatings

Acrylic coatings, like Humiseal 1B31, can be difficult to remove. Your best choice is the Heavy-Duty Flux Remover – SuprClean™. It is a formidable cleaner with a high Kb value. If it dries a little too quickly for this application, soak the parts in a bath of the solvents. Put a lid on the container so the fluid does not evaporate too quickly.

Urethane Coatings

Urethanes are challenging to remove. Generally, a powerful, slow-drying solvent will work best, if anything works at all. Try the Uncured ExPoxy™ Remover as one option. Usually, these coatings can be removed with a good, long soaking bath in the solvent. Put a cover on the bath to control solvent evaporation.

Epoxy Coatings

Epoxy coatings are very difficult. There is no benchtop-safe chemical which can remove a cured epoxy coating, except physical abrasion. If the coating has not cured (hardened) the Uncured ExPoxy™ Remover will be the best option. Usually, these coatings can be removed with a good, long soaking bath in the solvent. Put a cover on the bath to control solvent evaporation.

Paralene Coatings

Paralene is a military-style coating, very thin and rock-hard. It simply cannot be removed chemically.

SuprClean™ is a powerful, HFC-based fluid used for traditional (RMA) fluxes, solder pastes, plus oils, grease, some inks and for cleaning acrylic conformal coatings

Question 25

Which Cleaner is Best at Removing Silicones?

Accepted Answer

This inquiry comes from customers frequently. Just recently, a customer in aviation needed to remove a silicone-based adhesive. Another customer was removing a silicone conformal coating. MicroCare solves these problems with the best-selling No-Clean Flux Remover – VeriClean™ and the VOC-Free Flux Remover – UltraClean™.

Both UltraClean™ and VeriClean™ are based on the chemical “siloxane” which is a chemical “cousin” to silicones. Since “like dissolves like” in the chemical world, siloxanes dissolve silicone glues, inks and coatings quickly and easily. In one case study conducted by a large Texas computer manufacturer, VeriClean™ removed in two minutes a coating which had been taking 45 minutes to remove with more traditional solvents.

Both choices work great, work fast, have almost no smell, dry promptly, and are priced right. Give either of them a try. The longer the solvent sits on the component, the more cleaning it will do.

Special Note: Some companies have a need to swell but not permanently deform silicone tubing. This usually is performed to make it easier to snap together mechanical assemblies. In this application, a silicone swelling fluid based on siloxanes is the optimal choice.

Question 26

What Cleaner Can I use for Removing Marking Inks, Sharpie Inks and Pen Ink?

Accepted Answer

Inks are very tough to remove. The best place to start is to determine the type of ink. There are generally three types of inks commonly used: alcohol-based, solvent-based and soy-based. The best all-round ink remover used to be the ketone solvents, but their nasty aromas and questionable toxicity have forced most companies to phase them out. Which, of course, leads to your question.

Stencil, Squeegee and Misprint Cleaner – ScreenClean™ (#MCC-CDI) is your best first choice because it has been initially formulated as an ink remover. The Alcohol-Enhanced Flux Remover – ProClean™ will remove alcohol-based inks, but this is a mild cleaner and alcohol-based inks are fairly rare. Another unusual application for the popular No-Clean Flux Remover – VeriClean™ can remove silicone-based inks. When nothing else works, try the Heavy Duty Flux Remover – SuprClean™. We have seen it wipe away ball-point pen inks. We have tried it on computer housings, keyboards, printers and even silk ties. It works great. But be careful: it will eat soft plastics!

The MicroCare Stencil, Squeegee and Misprint Cleaner is packaged as a presaturated wipe

Question 27

Which Cleaner Works Best on Light Grease, Oils and Other Lubricants?

Accepted Answer

Until recently, there would have been only one recommendation and it would have stood out so far above all others you couldn’t even read the names of the second choice. The leader: the Uncured Epoxy Remover (#MCC-EPX). This cleaner is as good as than the old ozone-depleting 1,1,1-TCA, it dries reasonably quickly, is very acceptable environmentally, and it has very good toxicity ratings. The only drawback? It has a flashpoint, so it is not suitable for use in heated vapor degreasers or ultrasonic systems.

But now there is a new top dog in town: the Lead-Free Flux Remover – PowerClean™. This product was formulated first as a defluxer and then we discovered it is a great degreaser as well. It is nonflammable, dries quickly and has an excellent environmental record.

The Reflow Oven Cleaner is a water-based degreaser is with exceptional handling. It’s nonflammable and slow-drying, but it works best when warm. Since many degreasers have heating capabilities, it’s ideal in applications where parts can be soaked for an hour or two in a dipping tank.

For automated cleaning of large quantities of products, MicroCare recently launched another great choice: Tergo™ XCF2 Specialty Cleaning Fluid. As degreasers go, the material is unbeatable. If your degreasing problems are causing headaches, and using a vapor degreaser seems feasible, then check out the Tergo™ family of cleaning choices.

Of all of these choices, we would recommend PowerClean™ as a starting point: it’s ozone-safe, nonflammable, and almost odor-free. Most of these cleaners are not completely plastic-safe, so be careful where you use them. Always test on soft plastics before deploying these cleaners widely. Get some samples and try them.

Question 28

Which Cleaner Works Best on OA Fluxes and Pastes?

Accepted Answer

Water-soluble fluxes are also called organic acid (OA) fluxes. These are fluxes primarily composed of organic materials other than rosin or resin. Water-soluble fluxes and pastes provide good soldering results and bright solder joints because they are highly activated fluxes. This means they have good wetting action and a strong ability to prepare a clean surface for soldering. However, they are aggressive, which calls for extra precautions during cleaning of the assemblies to avoid flux contamination. They must be thoroughly cleaned or those aggressive activators will corrode the PCBs very quickly.

Cleaning OA fluxes and pastes is fast and easy with Alcohol-Enhanced Flux Remover – ProClean™ (#MCC-PRO). ProClean™ is a mild, plastic-safe, low-cost defluxer that cleans rosin fluxes, water-based OA fluxes, synthetic fluxes and most “no-cleans.” Totally plastic-safe, it cleans most leaded flux residues, solder pastes, organic residues and oils. It is relatively slow-drying, which gives operators enough time to clean flux residues without wasting a lot of fluid. Water-free, non-corrosive and ESD-safe, ProClean™ is highly suitable for all types of electronics, including through-hole and SMT boards, insulators, cables and connectors.

Another great choice is the General Purpose Flux Remover (#MCC-FRC). This is a versatile product that is affordable, nonflammable, easy to use and safe to store. It features speedy drying and almost no aroma. Suitable for all types of electronics, this flux remover can be used on through-hole and SMT boards, hybrids, cables and connectors. It is highly effective on all flux residues (including some hard-to-clean lead-free products) and can serve double-duty as a general purpose degreaser for light oils, grease and inks. With an ultra-low surface tension and high density, this product even cleans under tight-fitting BGA chips, dissolving and flushing residues away.

Question 29

Which Flux Remover Is Best on Ceramic Hybrid Circuits?

Accepted Answer

For the general precision defluxing of hybrid circuits, nothing can beat the Lead-Free Flux Remover - PowerClean™ (#MCC-PW2). This is a powerful cleaner, functionally equivalent to the old Freon® TMC or Genesolv® 2004. PowerClean™ dries fast, offers powerful cleaning on most fluxes, it's nonflammable, it has a very low aroma, and is easy to use and to store. It's a great choice.

A newer choice, but slightly milder, is the VOC- Free Flux Remover - UltraClean™. This is a medium-strength cleaner that is engineered for communities with the tightest restrictions on using VOCs.

An older answer is the General Purpose Degreaser (#MCC-AXL). Originally developed by DuPont for cleaning hybrids, this is a hydrocarbon solvent that it is derived from petroleum products. Plastic-safe and slow drying, it has a modest aroma and delivers moderately powerful cleaning. It represents a very good combination of characteristics.

Question 30

What's Best for Cleaning Under Low Clearance SMT Components?

Accepted Answer

Contamination is one of the primary drivers of field failures in electronics today. Corrosion and electrochemical migration (“ECM”) is directly caused by residues left on PCBs. Contamination-related failures are pervasive and have been observed on batteries, LCDs, PCBAs, wiring, switches, under coatings, over coatings, etc. The problem is expected to get worse as continued reductions in pitch between conductors makes future packaging more susceptible. Contaminants are concentrated under these low standoff devices.

This didn’t used to be a problem. Until the 1970s, almost all electronics were built from individual components, with the labor-intensive assembly of thousands of separate diodes and transistors. The miniaturization demanded by the space race led to the first computer chips called “plated through-hole” circuit board designs. The defining physical feature of a through-hole PCB are the “legs” that extend from the components. These chips have a high “stand-off” from the board which makes it easy to clean the rosin flux residues that migrated under the components.

The late 1980s saw the evolution to the first SMT “surface mount technology” components. Shorter legs and tighter stand-offs enabled more chips per-square centimeter, making the resulting tools “smarter.” Many chip designs, such as the popular QFP format, had 200+ electrical connections which made the chips extremely powerful.

But by the turn of the century, ball grid array (“BGA”) components were becoming commonplace. BGA components jammed even more transistors into the smallest possible package. Each chip supported thousands of tiny solder connections (hidden underneath the chip) which make them extremely rugged, even in harsh environments. BGA designs have stand-offs measured in microns. The increased use of leadless and bottom termination components (QFN, land grid array, etc.), multi-chip modules and other advanced component designs results in a reduction in standoff height which reduces the efficiency of cleaning.

These dense designs are difficult to clean, and cleaning is absolutely critical to longevity and performance. Specifically, heat from the component accelerates the reactions formed with salt complexes which can then cause corrosion or dendrite growth on the PCBs, causing the PCB to fail. Dense PCB designs run hot, so corrosion that might take years in a benign office environment can happen in just days in a hot, humid environment.

For best cleaning results, PCB fabricators should seek out cleaning fluids that are very pure and uncontaminated, with a high Kb value, with low surface tension and low viscosity. Water simply will not get under these tight-fitting components, and if somehow it does get under the chip it will rarely ever comes back out. For best results, consider the Heavy Duty Flux Remover — SuprClean™ (#MCC-SPR). Other good options are the No-Clean Flux Remover — VeriClean™ (#MCC-DC1) and the General Purpose Flux Remover (#MCC-FRC).

BGA components like this one link their electrical connections with thousands of tiny solder joint hidden beneath the component. These can be very difficult to clean with traditional liquids

Question 31

Which MicroCare Products Meet Mil-spec Cleaning Requirements?

Accepted Answer

Military customers know they must clean their electronics if they are going to get reliable performance under battlefield conditions. Many MicroCare solvents and cleaners have been and continue to be used for the cleaning of military devices, avionics systems, air frames, ground-based weapon systems and ground support equipment.

MicroCare cleaners can be used to remove fluxes and solder paste from mil-grade PCBs, to remove conformal coatings before rework or repair, to clean dusty or dirty connectors, and to cleaning housings and tools.

Military customers can be grouped into three 'clusters': (a) companies making new military products, (b) products being built/maintained to MIL-STD-2000, and then (c) companies making or repairing older mil-spec electronics.

For customers in the first group, many clients build to the SAE specs. (Note: The 'Society of Automotive Engineers' does not limit itself to just automobiles; 'automotive' means 'self-propelled' so cars, trains and ships fit into the category as well.) Oddly, there is no SAE specification for avionics cleaners. However, many avionics manufacturers use the MicroCare cleaners on their products. Companies using MicroCare cleaners include BAE, Marconi, Hamilton/Sunstrand, Raytheon, Boeing, L-3, Honeywell, Rockwell, Hughes, General Dynamics and Lockheed.

We have a smaller group of customers working to MIL-STD-2000, the world's first military 'performance-based' cleaning standard (which today has generally be replaced with new commercial standards). The Citrus-based Flux Remover (#MCC-EC7M) meets this old standard.

In addition, for the very oldest products carrying the strictest and least-flexible cleaning requirements, the Alcohol-Enhanced Flux Remover - ProClean™ (#MCC-PRO) meets WS-6538, among other specifications.

MicroCare is the world leader in benchtop precision cleaning. For almost four decades we've helped bring new tools and solvents to help the military reduce their costs while accomplishing their mission. If your military customers have any questions about these cleaners, please contact MicroCare right away.

Military electronics need to operate under challenging conditions, take a great deal of abuse and have an extremely long service life. Quality cleaning helps these tools keep soldiers safe.

Question 32

Which Cleaners Work Best in Ultrasonic Tanks or Dip Tanks?

Accepted Answer

Yes, MicroCare has a number of choices here. But for maximum safety there are some rules you will want to follow:

Given those criteria, it should be no surprise that water — even deionized water — is not a particularly good choice for these machines. Instead, MicroCare has excellent choices for you to consider.

For situations requiring a simple dip tank equipped with ultrasonics, such as the stencil cleaners made by JNJ Industries, SmartSonic and others, try the Aqueous Stencil Cleaner (#MCC-BGA). This product works great in small, desktop ultrasonic systems because it is powerful, non-foaming, slow drying (you don't lose a lot to evaporation), it holds a lot of contamination (you don't have to change the solvent very often) and it is inexpensive. Cleaner is water-based products and users can add small amounts of water to dilute the solvent and save money, with only a modest decrease in the cleaning horsepower.

For more complex cleaning applications, consider cleaning in vapor degreasers. MicroCare has a full-line of solvents for vapor cleaning and they deliver fast, consistent and highly affordable cleaning for many different applications.

Question 33

What is Causing White Residue on my PCBs?

Accepted Answer

White residues are the bane of the electronics industry. The white residues themselves usually (but not always) are salts, which are the “activators” in the fluxes. When these salts meet heat or other chemicals, white residues can result. These residues can corrode delicate circuits. There are dozens of different possible sources — the boards, the solvent and fluxes, the people, the processes, the way the fluxes and solder paste are stored, and even the weather. It is very hard to determine precisely what might be causing the problem.

Since the industry switched primarily to lead-free soldering materials, problems with white residues have skyrocketed. These materials use different ingredients, operate at higher temperatures and respond to solvents differently than the older products. MicroCare has introduced new cleaners specifically to help deal with these high-temperature issues.

But lead-free isn’t the only source of residues. For example, if somebody uses the wrong flux, white residues can result. If cleaning is not performed properly, white residues can result. Even improperly cured substrates can manifest white residues after reflow. So determining the true root cause can be tricky.

All too often, people blame the solvent because it’s the last chemical to touch the board even when the true cause is some other process or change. The good news is that you can be absolutely sure that the source of the problem is NOT contamination in the MicroCare solvent itself. All MicroCare cleaners are filtered to 0.2 microns. This means they are factory-pure. And — unlike some cleaning companies — we never use reclaimed (recycled) materials in our cleaning solvents.

The number one cause of complaints about PCB cleaning are white residues on the board. These usually are salt crystals, residues of imperfect cleaning.

So, what is causing the residues?

There are three likely places to look: the contamination, the solvent, and then the process.

First, look for a change in what you’re trying to clean. For example, have you just switched to lead-free? Or, did a spool of RMA solder get slipped into a “no clean” process? These material changes can cause unexpected residues and cleaning problems.

Next, look for a mismatch between the solvent and the contamination. If the residues are an even, smooth layer of white film across a large area this usually indicates you have the wrong solvent for that flux. For example, the Heavy-Duty Flux Remover – SuprClean™ generally will leave white residues on “no-clean” fluxes. As another example, once in a great while the ingredients in the Alcohol- Enhanced Flux Remover – ProClean™ also will react with “no clean ” fluxes and produce white residues. Change the solvent and the problem goes away.

Lastly, check the cleaning process. When people report white residue problems, it often is a process problem. Look for streaks or spots of white residues. These are the indicators of improper cleaning technique. If your people are using the TriggerGrip™ circuit board cleaning system, check and see if they are using it correctly. Remember the four-step cleaning process: Wet, Scrub, Rinse and Dry.

To select a solvent, use this very simplified progression from the mildest cleaners to the strongest:

Alcohol-Enhanced Flux Remover – ProClean™ → No-Clean Flux Remover – VeriClean™ → Lead-Free Flux Remover – PowerClean™

If all the other possibilities have been eliminated, contact MicroCare for more personalized assistance.

Question 34

Does MicroCare Have Any Replacements for HCFC-225?

Accepted Answer

HCFC-225 was an “Class II” ozone-depleting substance and is no longer made in the USA or Japan. In the 1980s, in response to the depletion of the ozone layer, more than 100 nations worked together on a treaty called “the Montreal Protocol.” This treaty set the rules for eliminating ozone-depleting substances around the globe. The first chemicals to go were the refrigerants and solvents called CFCs, halogenated fire suppressants and other “Class I ozone-depleting substances.” Then the less damaging HCFCs, which are “Class II” products, had to go. The last HCFC on the market today was HCFC-225, made in Japan, and it was phased out in 2015. MicroCare has never packaged HCFC-225, which is also called AsahiKlean and other names. While there are no restrictions on using HCFC cleaners in the U.S., since nobody has produced the fluid for a number of years it has become very scarce and expensive. MicroCare has many new, ozone-safe solvents that are perfect answers to replace HCFC- 225 solvents.

Does This Involve “SNAP”?

Yes, it does. In the USA, the Clean Air Act defines the “Significant New Alternatives Program” (SNAP). This process prevents people from switching from one ozone-depleting chemical to something worse. Customers will need to switch to new SNAP-accepted alternatives to replace HCFC-225. The first step they should take with any substitute is to confirm the proposed alternative is SNAP- approved as a replacement for HCFC-225 in their specific application. All of the MicroCare alternatives are “SNAP” approved.

So What Are the Alternatives?

If you are still using HCFC-225, it’s time to RUN, not walk, to the alternative choices. You’ve put this off for years; the time has come.

There are a number of great alternatives to consider for cleaning on the benchtop:

If you were using HCFC-225 in vapor degreasers, see the excellent cleaning options from MicroCare in the Precision Cleaning web site.

The 'ozone hole' over Antarctica has shrunk by 4 million square kilometers from 2002-2015, mostly due to the reduction in ozone-depleting solvents. Source: BCC

Question 35

What's the Best Replacement for nPB Aerosols?

Accepted Answer

The U.S. Environmental Protection Agency, State OSHA offices and governments around the world have been considering measures to reduce and restrict the uses of nPB, TCE, perc and methylene chloride. Here’s a quick look at the particular situation involving nPB:

Normal propyl bromide (also called nPB, 1-bromopropane, CAS #106-94-5) is an affordable, nonflammable, versatile industrial chemical used in a wide variety of applications (e.g., carrier fluid for adhesives, to clean fluxes from printed circuit boards, degrease metal and ceramic parts, cleaning optics, aerospace maintenance and as an intermediate product in the production of certain synthetic fibers). It has a very high Kb value and operates at higher temperatures than low-boiling solvents, which is useful in many applications.

In 2014 the American Conference of Governmental Industrial Hygienists (ACGIH) concluded the 8-hour time-weighted average exposure limit for 1-bromopropane should be reduced from 10 parts per million (ppm) to 0.1 ppm. In 2016, the U.S. Environmental Protection Agency (EPA) added nPB to the Toxic Release Inventory which requires companies using nPB to file an annual report on the emissions and disposal of nPB. It is now almost impossible to use nPB in an industrial setting and maintain a worker exposure below the minimum safety standard.

MicroCare has never packaged nPB in aerosol packages, but many other companies have. This presents a serious safety hazard to workers. MicroCare offers advice and engineering expertise to customers to help them use nPB and other solvents safely. These include:

If you were using nPB in a vapor degreaser, learn more about the new Tergo™ performance fluids from MicroCare which are excellent replacements for nPB.

The Universal Flux Remover is an ultra-low GWP formulation that is completely free of HFC ingredients and is a good replacement for nPB as well

Question 36

Can I Get HCFC-141b Alternatives for Cleaning?

Accepted Answer

Genesolv 2004, Arklone 141b and other cleaners based on the hydrochlorofluorocarbon molecule HCFC-141b has been phased-out of production and is no longer available from MicroCare and other reputable firms. On a label or MSDS sheet you might see brand names such as “Genesolv®” or “Forane.” The cleaner’s precise chemical name is dichlorofluoroethane and it usually will be further identified as “CAS #1717-00-6.”

MicroCare packaged four products using HCFC-141b: Genesolv® 2004, Genesolv® 2010, HyperClean™ and Precision Contact Cleaner II. There are no restrictions on using HCFC cleaners in the U.S. But, since nobody has produced the fluid since the end of 2002 (except in China) it has become very scarce and expensive. MicroCare has many new, ozone-safe solvents that are perfect answers to replace HCFC- 141b solvents.

Was HCFC-141b a Big Problem for the Environment?

Under the terms of the Montreal Protocol, all of the production and importation of HCFC-141b ended in the U.S. on December 31, 2002. The general phase-out schedules were defined years ago. This effort was based on research by the British in the 1960s detected changes in the ozone layer in the Antarctic. It took almost another decade to figure out the cause, and it was Mario Molina, a lowly post-graduate researcher in California, who first realised that man-made chemicals such as CFCs were damaging the ozone layer. Fortunately his mentor, Dr. Sherwood Rowland, took his findings seriously and the pair went on to publish an article in 1974 in which they spelled out the dangers of continued use of CFCs.

In the 1980s, in response to the depletion of the ozone layer, more than 100 nations worked together on a treaty called “the Montreal Protocol.” This treaty set the rules for eliminating ozone-depleting substances around the globe. The first chemicals to go were the refrigerants and solvents called CFCs, halogenated fire suppressants and other “Class I ozone-depleting substances.” Then the less damaging HCFCs, which are “Class II” products, had to go. The last HCFC on the market today was HCFC-225, made in Japan, and it was phased out in 2015.

The good news is that the ozone layer is rebuilding itself. Recent research (2015) suggests first clear evidence that the ozone layer above Antarctica is starting to heal. As of September 2015 the “ozone hole” was around 4 million square kilometers smaller than in the year 2000 — an area roughly the size of India. The gains have been credited to the long term phase-out of the ozone-destroying chemicals.

How Much HCFC-141b Was Produced?

Yes, it was. This cleaner had become more popular than anybody expected thirty years ago. Since then more than $50 million of this product was sold across the U.S. each year, about 10 million pounds just in the electronics industry. At it’s peak, about 200 million pounds of HCFC-141b was used around the world annually. The EPA was worried that as long as the electronics industry was “addicted” to convenient and inexpensive HCFC-141b, the ozone layer would never regenerate.

Does This Involve “SNAP”?

Yes, it does. The Clean Air Act defines the “Significant New Alternatives Program” (SNAP). This process prevents people from switching from one ozone-depleting chemical to something worse. Customers will need to switch to new SNAP-accepted alternatives to replace HCFC-141b. The first step they should take with any substitute is to confirm the proposed alternative is SNAP- approved as a replacement for HCFC-141b in their specific application. All of the MicroCare alternatives are “SNAP” approved.

So What Are the Alternatives?

If you are still using HCFC-141b, it’s time to RUN, not walk, to the alternative choices. You’ve put this off for years; the time has come.

There are a number of great alternatives to consider:

Samples are available from MicroCare.

The “ozone hole” over Antarctica has shrunk by 4 million square kilometers from 2002-2015, mostly due to the reduction in ozone-depleting solvents. Source: BCC

Question 37

Are MicroCare Products Safe or Hazardous?

Accepted Answer

There is no standardized “cert” about hazards and safety but, in general, the MicroCare cleaners are just about as safe as you can get. Their exact performance is documented on the Product Specs and on the Safety Data Sheets (SDS) prepared for every cleaning fluid. For European customers, all MicroCare products are REACH registered for safety. Let’s take a look at the details:

(NOTE: The following discussion applies to customers in the US. Safety rules change in every country; check your own local regulations for the details as they apply to your company.)

In the US, a chemical can be considered “hazardous” because of (a) the toxicity of the chemical itself, (b) the flammability of the chemical, (c) the packaging of the chemical, (d) the reactivity of the chemical, and/or (e) the applications in which it is used.

For example, many MicroCare products are sold in aerosol packaging. When shipped to a customer by air, they will be considered hazardous. This is because the aerosols are “pressurized containers” and pose some slight safety risk to airplanes if they exploded in flight. So the packaging can make a big difference.

As an example, the Lead-Free Flux Remover – PowerClean™ (#MCC-PW210A) is safer because it is nonflammable, and so customers might choose PowerClean for that reason. This is documented on the Product Specification under “Flash Point” and “Flammability Rating.”

Another option is to improve the handling of the chemical. The TriggerGrip™ system minimizes worker exposures, and is much safer than messy dip-and-brush cleaning on PCBs.

In terms of toxicity (long-term skin, eye and breathing exposure to the chemicals), all three of these products are very safe. This is measured by the Threshold Limit Value (TLV, AEL, PEL, or similar term) assigned to the chemical by government safety scientists. This is an attempt to measure the greatest amount of solvent a person could be exposed to for 8 hours each day, five days a week, for a thirty-year working life AND have no health effects at all. A high score is good (a perfect score is 1,000 parts per million), and a low score (say, 5 or 25 ppm) is considered pretty dangerous. VeriClean, for example, has a TLV of 200 ppm, which is right in the middle of the average scores. Alcohol is 400 ppm. Some solvents (not provided by MicroCare) are in the 10 ppm range, and we think that is sufficiently dangerous that we won’t package them in aerosols or let novice users buy them in bulk.

In short, if a company is concerned about hazards to workers and to their factories, they need to read the product specifications and SDS sheets. These documents have all the important facts included on them, and we take great pride in offering complete, accurate and up-to-date information on them.

Messy aerosol sprays volatilize the cleaning fluid, exposing workers to fumes. The excess fluid also can puddle below the cleaning site, creating a flammability hazard if the solvent has flammable characteristics

Question 38

Are Any MicroCare Products Nonflammable?

Accepted Answer

Benchtop cleaning fluids must meet a number of criteria to make them viable choices for workers to use. Worker safety is the paramount issue, topping all others. A proposed cleaner must have exceptionally good toxicity profiles due and preferably with no flashpoint. MicroCare offers a number of nonflammable choices which will help you lower costs and improve worker safety:

Universal Flux Remover (#MCC-UFR)
Heavy Duty Flux Remover – SuprClean™ (#MCC-SPR)
Lead-Free Flux Remover – PowerClean™ (#MCC-PW2)
General Purpose Flux Remover (#MCC-FRC)

In addition, only MicroCare offers the TriggerGrip™ cleaning system which makes it easy to use flammable solvents safely.

Question 39

Do Flammable Cleaners Create a Hazard on the Rework Bench?

Accepted Answer

Solvent flammability is a very difficult issue. The chemical behavior itself is difficult to measure precisely because it varies greatly, according to circumstances. Flammability is difficult to manage because of the environment in which the solvent is packaged, stored, shipped and used; and the risk can be difficult to predict because of exogenous factors such as employee training.

Every country regulates flammability differently. In the US in years past, there were three categories of flammability: nonflammable, combustible and flammable. These were based on 'closed cup' and 'open cup tests' which had defined ANSI standard testing protocols, and the 'flame extension tests' which were used exclusively on aerosols. Naturally, Canada and Europe had different standards and tests. The Globally Harmonized System of packaging and labelling was deployed in 2015 and the rules changed again. Although flammability standards are NOT uniform globally they generally are moving in the direction of making it more difficult to claim the golden 'nonflammable' status. For more details about flammability testing, see your company's local health, environmental and safety (HES) experts.

Messy aerosol sprays volatilize the cleaning fluid, exposing workers to fumes. The excess fluid also can puddle below the cleaning site, creating a flammability hazard if the solvent has flammable characteristics

Additionally, there is a move to use cleaning fluids that are more gentle on the environment. High global warming potential fluids (GWP) often are nonflammable, but low GWP fluids often are volatile organic compounds (VOCs) that contribute to smog in cities. There is a trend to ban certain nonflammable aerosol propellants that have high GWP ratings but the effect is to make the products more flammable; it's becoming harder to pass the flammability test with the new ingredeints that have improved environmental characteristics. Aerosol companies around the globe are wrestling with this dilemma. In the photo below, all three cans contain roughly the same ingredients but the two cans on the left use a nonflammable propellant; the product on the right does not. The effect of a flammable propellant is obvious. [Note: The is NOT a photo of an ANSI-standard test, merely an illustrative demo.]

Three different aerosol cleaners tested for flammability show very different results. See text for explanations.

MicroCare has a different 'take' on the problem. MicroCare sells both flammable and nonflammable cleaning fluids, in both aerosol and bulk packaging. Properly used by trained staff, they work great. However, it is hard for a client to be sure the product is always properly used. That's why MicroCare invented the TriggerGrip™ cleaning system. The TriggerGrip™ avoids wasteful solvent over-spray. Only exactly the minimum amount of solvent is used, and it is only applied exactly where needed. There is no puddled liquid to burn. This makes it much safer to use low-cost flammable cleaners.

Question 40

Are There Toxicity Issues with Trans?

Accepted Answer

As noted elsewhere in this web site, MicroCare is proud to be one of the first companies in the industry to commercialize cleaning products using 1,2-trans-dichloroethylene which is also known by the CAS #156-60-5 but more commonly called “trans”.

We often get inquiries about trans, mainly because it is such a new ingredient in many solvents. But once in a while we get inquiries which question the “dangers” of trans. Since there is some bad information in the market place about trans. Let’s take a moment to review the details. Most often, the question revolves around the two most common safety issues: flammability and/or toxicity.

Flammability

Many customers worry about the flammability of trans. We use standardized tests to measure flammability and can confirm that trans is highly flammable, similar to alcohol. But trans is rarely used alone. For example, it is a major ingredient in our Heavy Duty Flux Remover – SuprClean™ (#MCC-SPR), one of MicroCare’s most popular cleaners. Despite containing about 40% trans, SuprClean™ is completely nonflammable. How does that happen?

The solvent is nonflammable because MicroCare uses an HFC dilutant AND an HFC propellant which are nonflammable. These ingredients suppress the flammability of other ingredients. This suppression factor works very well. In fact, at MicroCare we can recall a competitor had a salesman actually try to show their products were safer than MicroCare’s solvents. So he sprayed a competing solvent and a MicroCare solvent into two glasses and dropped a match into them. The MicroCare solvent put the match out while the competing product started to burn. Naturally, this was pretty embarrassing for that salesman. But the point is, our packaging and blending helps make these products safer. (NOTE: This is NOT the recommended way to test for flammability!)

Three different aerosol cleaners tested for flammability show very different results. See text for explanations.

It’s useful to note that that the industry is moving to a newer, more comprehensive method of testing flammability; we’ll publish those details when they become available. In general, using nonflammable solvents like SuprClean™ will be a big boost for safety when compared, for example, to using IPA in a dip-and-brush mode.

Toxicity

MicroCare tries to be pro-active and solve toxicity issues before they become problems. And trans clearly is one of the answers, not one of the problems.

There are several “versions” of trans and one of them is more toxic than the other. Trans is a molecule consisting of two carbon atoms, two chlorine atoms and two hydrogen atoms. The carbon atoms are always in the center with a strong double-bond between them. But the chlorine and the hydrogen can be arranged several different ways. If they are arranged in the “trans” form, or trans “isomer” as the chemists call it, there is one chlorine and one hydrogen atom attached to each carbon atom. This is very symmetrical, stable and safe. ACGIH has assigned the trans isomer a threshold limit value (TLV) of 200 ppm, which is a very good “safety score” in today’s world.

But if both chlorines are locked on to one carbon and both hydrogen atoms are over on the other side of the molecule, the molecule is not symmetrical. This is the “cis” formation. In the pure form the “cis” isomer has a toxicity level of 10 ppm, which is a low score (highly toxic). A solvent made of purely the “cis” isomer would be a very nasty product indeed.

Now, when people make trans, a small portion of “cis” also is made in the same reaction. In the old days, people just shrugged their shoulders and said “well, that’s how it comes out.” But in today’s world we do better. Our factory actually filters out the “cis” isomer using temperature and other processes, and throws the “cis” back into the tank for further processing. So the “trans” found in MicroCare solvents is a very, very pure “trans” isomer.

Is there some “cis” in the solvent? Probably. But those levels are so low that they are not a health and safety factor in the slightest. The trans in MicroCare products is clean, pure and very safe when used as suggested by MicroCare.

Dispensing Control

Which brings us back to the TriggerGrip™ dispensing system. This has been and remains one of our most important innovations. It completely eliminates the messy, wasteful and dangerous over-spray from “high pressure” aerosols. It also delivers better and cheaper cleaning than the classic “dip-and-brush” system. In short, there is no better, safer or cheaper way to clean a PCB than with a powerful safe solvent, like SuprClean™, and the Trigger Grip dispenser.

The calculated overall threshhold limit value for SuprClean™ is about 200 ppm. This means you can inhale 200 ppm of SuprClean™ for 8 hours a day, for a 30-year career, and have no noticeable ill-effects. (In fact, the 8-hour Time- Weighted Average is actually 1/10th of the “no observed effects level” — which means it really is about 4,000 ppm — as still a further buffer for safety.) See the SDS sheet for each product for more details.

However, in tests with the TriggerGrip™ dispensing system the worst (highest) exposure levels observed were in the 15-20 ppm range for an 8-hour work day. This means that customers using SuprClean™ with the TriggerGrip™ tool have a 10-fold buffer of safety before they even begin to reach exposure levels of concern. That’s another reason why we think the TriggerGrip™ dispenser is such a good idea.

If you still have questions or concerns, contact MicroCare for more details.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Question 41

How Can I Ensure My People Are Handling Chemicals Properly?

Accepted Answer

We suggest deploying the TriggerGrip™ system for all your techs doing PCB cleaning. The whole point of the TriggerGrip™ system is to use the solvent properly — that is, to produce cleaner PCBs faster, more safely, with less solvent. This immediately translates into a cost saving: with the TriggerGrip™ system you buy fewer cans of solvent.

Once you have reduced the amount of chemicals in use, a whole host of good things happen:

Since you use less solvent, your cleaning costs go down.
Since you use less solvent, people get less chemical on their hands, in their eyes, and in their lungs, boosting safety.
Since the solvent is pre-packaged, your risk of spilled chemicals and fire hazards is reduced.
Since you are never pouring solvents from pails and drums, you always have the right safety data because it’s right on the can.
Since the cans can be tracked, you can monitor which tech is using the solvent.

Proper training for your people also helps wonderfully. MicroCare offers a 7-minute training video that shows your team how to connect the TriggerGrip™ system, how to use the device, and then how to disconnect it safely. You can watch it on this web site, download it from YouTube or just contact MicroCare and we’ll get you copies for your training team.

There’s no reason to waste solvent. Techs should be trained to only use what they need, and the TriggerGrip™ system reduces their needs. The TriggerGrip™ dispensing system is simply a better way.

TriggerGrip™ system being used with a strong solvent to clean a PCB

Question 42

My People Are Complaining About Solvent Fumes. What Can I Do?

Accepted Answer

Let's assume your people are cleaning PCBs or stencils by hand. Try this three-step process to improve worker safety.

Check the Ventilation

First and foremost, you must make sure your work areas are properly ventilated. How do we define 'properly ventilated'? If you lit a cigarette in the work area, would the smoke from your cigarette rise straight to the ceiling, or would it move off to one side fairly quickly and be dissipated through the room? If it rises straight to the ceiling, your ventilation would be considered poor. Good ventilation is essential in a modern factory. It improves worker health, reduces absenteeism, and boosts productivity. You need to install fans in the area, open windows, install dedicated fume extraction equipment, and/or get your facility manger to turn up the A/C a bit.

Switch to the TriggerGrip™ Cleaning System

Open trays of solvent are obviously a bad idea. Improper use of cleaning machines can create clouds of fumes that could choke a horse. The TriggerGrip™ system from MicroCare (#MCC-ESD) dramatically cuts solvent waste and thereby minimizes solvent fumes. Slow-flow brushes on your TriggerGrip™ can further reduce solvent consumption and fumes. Also, be sure everybody is using them properly. If in doubt, call your sales rep for refresher training or get a copy of the TriggerGrip™ training video.

The TriggerGrip™ cleaning system connects to a MicroCare aerosol can and delivers fast, better and safer benchtop cleaning

Change Your Solvent

You might want to change your solvent. Today's solvents tend to be fast-drying, nonflammable, powerful and easy to use. So switching to a low-aroma solvent such as the Lead-Free Flux Remover - PowerClean™ (#MCC-PW2) the No-Clean Flux Remover - VeriClean™ (#MCC-DC1) might make a big difference in your work area.

Question 43

What Are the NFPA Ratings for the MicroCare Cleaners?

Accepted Answer

All of the “hazard” information about a chemical made in the USA is summarized in the NFPA ratings assigned to every product. (NFPA stands for National Fire Protection Agency.) An NFPA rating often is displayed in a diamond pattern and includes four codes, like this:

“Health” means impact upon human health and well-being; a zero or 1 rating is very good. “Fire” measures how easily something can begin to burn and what happens when it does burn; a 1 or 2 is OK but a “3” would be a highly flammable material and you would want to store it and use it carefully. “Reactivity” specifically pertains to how the chemical mixes with water, as during a fire-fighting event. “0” is great – it means you can spray water on the product and no chemical reaction happens. In text forms, NFPA ratings often are shown like this:

NFPA Health: 1; Fire: 2; Reactivity: 0

Again, and confusingly when compared to TLV ratings, LOW scores are better and HIGH scores (like a “3”) are more risky.

In short, if a customer is concerned about hazards to workers and to their factories, the NFPA ratings can be very helpful. However, these ratings have been generally replaced by the new Globally Harmonized Standards (GHS) which came into effect in 2015. Since NFPA ratings were only used in the USA, the GHS standards are better for products around the world. The MicroCare product specs have all the important facts included on them, and we take great pride in offering complete, accurate and up-to-date information on them.

Question 44

Do I Need Gloves When Working With  MicroCare Cleaners?

Accepted Answer

While casual and intermittent skin contact with most of the MicroCare cleaners does not represent a significant health risk, wearing gloves is certainly is a good practice, especially if skin contact is likely and prolonged. This is particularly true when cleaning stencils by hand, using the presaturated wipes. Gloves, splash goggles, aprons (when handling open drums) and safety shoes with steel toes are highly recommended.

Common sense strongly recommends that prolonged or repetitive skin contact with any solvent or chemical should be avoided. After all, the MicroCare solvents are defluxers and degreasers. They are designed to remove oils and grease. This can result in the temporary drying, itching, swelling and roughening of the skin. This temporary irritation of sensitive skin is called temporary local dermatitis. Healing is rapid after the exposure ceases. But why work so hard? Wear gloves or finger cots and stop worrying about it.

When using solvents for cleaning SMT stencils and other production equipment, most experts recommend the use of gloves

Protective Clothing Enhances Worker Safety

Whichever solvent you select, you should use gloves and other protective clothing if there is any risk of skin or eye contact. There is a very good web site which has excellent technical data about the huge array of glove choices available on the market. It’s organized by the Office of Environmental Health & Safety (EHS, formerly The Office of Radiation, Chemical & Biological Safety (ORCBS), at the Michigan State University) so it’s not tied to any one manufacturer or brand. When you identify a chemical it suggests the best type of glove to use. In the color chart, you’re looking for gloves rated in white or green. When selecting gloves, check the SDS sheet to get the EXACT chemical name or CAS number for the solvent you are using; different solvents require different types of gloves.

As a general rule for MicroCare products, latex gloves work adequately. In some applications a more durable two-part glove might be necessary. Chose the powderless option if it is important to control nonvolatile residues in your production process. These are widely available from quality distributors everywhere.

If you don’t have time to go to the ORCBS site, then select the best impervious gloves and protective clothing you can find if there is any risk of skin contact. Gloves, splash goggles, aprons (when handling open drums) and safety shoes with steel toes are highly recommended.

Question 45

What's the Shelf Life of MicroCare™ Cleaners?

Accepted Answer

MicroCare cleaners generally do not have any shelf life restrictions. In other words, MicroCare products have an indefinite or unrestricted shelf life. This guarantee means that if the products are unopened, properly handled and carefully stored they will remain safe and effective for use for many years. This includes our flux removers and presaturated wipes.

The date of manufacture is printed on the bottom of every aerosol can. The date of manufacture can also be determined by the lot number which is printed on the bottom of every aerosol can and pre-saturated tub and refill as well as on the outside of each case. Lot numbers are printed on the product labels for gallon, pail, and drum product. The first two digits represent the year in which the solvent was manufactured (e.g. lot number 21213 was manufactured in 2021 and lot number 17182 was manufactured in 2017).

The last three digits represent the day of the year; this can be calculated using the Julian Code (e.g. 21213 was manufactured in 2021 on the 213th day of the year).

If you have any questions, please feel free to contact MicroCare, LLC. at 800-638-0125.

“Proper” handling is defined as a reasonably cool, dry location out of direct sunlight and away from extreme heat. Any business facility in which people work comfortably is sufficiently cool. Unacceptable locations would be (a) outside exposed to rain; (b) on a hot loading dock exposed to direct summer sunlight for weeks at a time; or (c) in an unheated truck during winter months in Stockholm, just to pick a few examples. Also, do not store metal containers directly on concrete floors or the containers will rust. MicroCare is not responsible for products improperly stored.

Obviously, as soon as the container is opened the shelf life of the product is reduced. Opened containers should be used first and emptied as soon as practicable. It is common and unremarkable to find unopened containers of Micro Care products which work well after five and even eight years in storage.

Micro Care is aware that few companies in the industry offer an unlimited shelf life warranty. But we are extremely comfortable with our products, packaging and manufacturing processes. We feel this guarantee is clearly justified and easily fulfilled. If you have any questions regarding this unusual quality guarantee, please contact MicroCare directly.

Question 46

What Is the VOC Content of the MicroCare Flux Removers?

Accepted Answer

On the MicroCare Technical Data Sheets you will find a reference to the “non-exempt organic content.” This is the VOC content. You also can find this value on the flux remover can itself and on the SDS sheet.

In most cases, VOC content is expressed in grams-per-liter which allows an accurate comparison across materials with different specific gravities and at different temperatures. Check the product specs and the SDS sheets for the VOC content of other MicroCare products.

Low-VOC Choices from MicroCare

MicroCare engineers have reformulated many of the cleaning products for reduced VOC levels. Here’s just a short list, as some examples:

All MicroCare products have their non-exempt organic content listed on their product spec sheet, the SDS sheet, and on the can label, so you can always tell the VOC impact of the different selections. However, every community has different rules, so the savvy engineer will be careful to check their regulations before making a final selection. For example, California’s CARB rules regulate a chemical by both the ingredients AND the application, so an acceptable solvent for cleaning electronics may not be an acceptable choice for washing windows. Check the rules in your area.

The VOC-Free Flux Remover is engineered for regions where local air quality rules prohibit traditional cleaning fluids

Question 47

What Are VOCs? Which MicroCare Products Contain VOCs?

Accepted Answer

Volatile Organic Compounds (VOCs) are the primary sources of low-altitude smog. 'Organic' means the chemical comes from something that used to be alive; 'Volatile' means it evaporates quickly; 'Compound' means it's a complex molecule containing many ingredients and not just a simple element. If a VOC has a long atmospheric life, it will react with sunlight and cause smog.

The most common VOC is gasoline, which comes from dead dinosaurs and is responsible for about 40% of the smog we see. Paints are loaded with alcohol — another VOC — and when paints dry the alcohol evaporates and forms smog, too. VOCs are everywhere.

(Note: VOC-exempt is a special category of chemistries with very short duration in the atmosphere and hence do not contribute to smog.)

Low-VOC Choices from MicroCare

MicroCare engineers have reformulated many of the cleaning products for reduced VOC levels. Here’s just a short list, as some examples:

The VOC-Free Flux Remover – UltraClean™ (#MCC-VOC) contains no VOCs and is specifically engineered for those markets with tight VOC restrictions, such as California, Texas and parts of the EU. In terms of performance, it is a highly effective circuit cleaner, offering superior results on “no-clean” fluxes and very good cleaning on rosin and lead-free fluxes as well. This product also easily removes silicone conformal coatings and silicone glues. It’s an excellent choice for defluxing circuit boards during rework and repair. Importantly, this fast-drying fluid is the strongest cleaner on the market in its class.
The VOC value for No-Clean Flux Remover – VeriClean™ (#MCC-DC1) is 87 grams per liter.
The No-Clean Flux Remover Pen is 87 grams per liter.
The Polar Flux Remover is 72 grams per liter.
The RMA Flux Remover Cleaning Pen is 72 grams per liter.
The Universal Flux Remover (#MCC-UFR10A) is 59 grams per liter. Medium-strength, fast-drying, this product is available anywhere in the world without restriction.
The Universal Contact Cleaner (#MCC-CCH10A) is 59 grams per liter.
The Reflow Oven Cleaner (#MCC-ROC) is 50 grams per liter.
Some of the slower-drying solvents are borderline VOCs as defined by their slow evaporation rate. This means they may not be regulated in some communities. The Citrus-based Flux Remover (#MCC-EC7M) and the TidyPen2™ (#MCC-P02) all are 100% slow-drying organics, so they may (or may not) be regulated as VOCs in different communities.

All MicroCare products have their non-exempt organic content listed on their product spec sheet, the SDS sheet, and on the can label, so you can always tell the VOC impact of the different selections. However, every community has different rules, so the savvy engineer will be careful to check their regulations before making a final selection. For example, California’s CARB rules regulate a chemical by both the ingredients AND the application, so an acceptable solvent for cleaning electronics may not be an acceptable choice for washing windows. Check the rules in your area.

The VOC-Free Flux Remover is engineered for regions where local air quality rules prohibit traditional cleaning fluids

Question 48

Which MicroCare Cleaners Contain VOCs?

Accepted Answer

Volatile Organic Compounds (VOCs) are the primary sources of low-altitude smog. “Organic” means the chemical contains carbon atomas and that usually means it comes from something that used to be alive; “Volatile” means it evaporates quickly; “Compound” means it’s a complex molecule containing many ingredients and not just a simple element.

VOCs contribute to smog in our cities. The most common VOC is gasoline, which comes from dead dinosaurs and is responsible for about 40% of the smog we see. Paints are loaded with VOC which evaporate when the paint dries. VOCs are everywhere.

Low-VOC Choices from MicroCare

MicroCare engineers have reformulated many of the cleaning products for reduced VOC levels. Here’s just a short list, as some examples:

All MicroCare products have their non-exempt organic content listed on their product spec sheet, the SDS sheet, and on the can label, so you can always tell the VOC impact of the different selections. However, every community has different rules, so the savvy engineer will be careful to check their regulations before making a final selection. For example, California’s CARB rules regulate a chemical by both the ingredients AND the application, so an acceptable solvent for cleaning electronics may not be an acceptable choice for washing windows. Check the rules in your area.

The VOC-Free Flux Remover is engineered for regions where local air quality rules prohibit traditional cleaning fluids

Question 49

What Does It Mean to Be 'VOC Exempt'? Is the Chemical Still a VOC?

Accepted Answer

As noted elsewhere in this web site, a VOC is an organic chemical (containing carbon) which can evaporate and remain in the atmosphere. While these materials float in the atmosphere the VOCs react with sunlight and can contribute to smog in cities. However, to be a harmful VOC the organics must have a significant atmospheric life span (measured in months) and be reactive in sunlight, because it is the reaction with sunlight that breaks the VOCs down into the smog.

Low-VOC Choices from MicroCare

MicroCare engineers have reformulated many of the cleaning products for reduced VOC levels. Here’s just a short list, as some examples:

All MicroCare products have their non-exempt organic content listed on their product spec sheet, the SDS sheet, and on the can label, so you can always tell the VOC impact of the different selections. However, every community has different rules, so the savvy engineer will be careful to check their regulations before making a final selection. For example, California’s CARB rules regulate a chemical by both the ingredients AND the application, so an acceptable solvent for cleaning electronics may not be an acceptable choice for washing windows. Check the rules in your area.

The VOC-Free Flux Remover is engineered for regions where local air quality rules are strict

The air quality in cities can be very poor, mostly due to VOC emissions in the atmosphere. This photo is Mexico City in 2010.

Question 50

Is Global Warming a Problem With Any MicroCare Products?

Accepted Answer

The short answer is, maybe. Many of the cleaners used to replace alcohols, old- style chlorinated solvents, plus HCFCs and CFCs, all have Global Warming Potential (GWP) ratings of some degree or another. Careful engineers will need to determine which solvent works best in their application while minimizing the GWP. Most MicroCare product specifications list the solvent's 'Global Warming Impact' (GWP) when it is provided by the chemical manufacturers. Lower scores are better. The summary below might help you make a proper selection:

Low GWP Solvents

If you desire to use a low Global Warming Impact cleaning fluid, select the VOC-Free Flux Remover - UltraClean™ (#MCC-VOC) or the Universal Flux Remover (#MCC- UFR10A). Both are fast-drying solvents, with a very brief atmospheric life; low odor; great on no-clean fluxes; affordably priced. However, they may not be strong enough for every application, and UltraClean™ is flammable.

Low GWP 'Canned Air'

For customers in Europe, there is a new option: HFO-based cleaners. Today, this exciting new ingredient is used in the 'precision duster' and 'circuit chiller' aerosols (as well as two solvents, ProClean™ EU and VeriClean™ EU engineered by MicroCare for customers in Europe. Their ingredients have less than 1% of the global warming impact of older-style products while retaining the nonflammable status so important for worker safety.

Special Note about the Environment

Global temperature variation from the norm in 2015. Source: GISS

Readers should be aware there is a 'Catch 22' to the effort to phase- out global warming solvents. With the exception of the HFO-based products, UltraClean™ and VeriClean™, most products with low GWP ratings probably will be a high VOC ('volatile organic compound') solvent. VOCs contribute to low-altitude smog, so if the air in your city is brown then switching to a high VOC/low GWP cleaner may not be the best idea. In fact, it may not even be permitted by local air quality regulators. (Search these FAQs for more details on 'VOCs.') Conversely, many products with low VOC content (a good choice for fighting against smog) have high GWP scores. So in general if you're worried about Global Warming you will want to use a high-VOC cleaner. If you're worried about VOCs, you're almost for certain headed back towards solvents with higher GWP ratings unless you can use VeriClean™ EU. And here's the real rub: none of this deals with other pressing issues like worker safety, waste disposal or affordability. Those are another group of issues for the savvy engineer to deal with. It's a tough call. But don't worry -- in the next few years MicroCare will be going further with new solvents and technologies, and introducing new cleaners using make even more progress towards protecting the environment. If you have questions, contact MicroCare where our experts can help sort out your options.

Question 51

Do MicroCare Aerosol Products Damage the Ozone Layer?

Accepted Answer

No, there are no MicroCare products made with any ozone-depleting substances. In years past, MicroCare package products using HCFC-141b, 1,1,1-TCA, and CFCs. But those products were all phased-out years — even decades — ago, as the world became aware of the damage they were doing to the environment. MicroCare has many new, ozone-safe solvents that are perfect answers to replace HCFC- 141b solvents.

What Are the Alternatives?

If you are still using one of those ozone-depleting solvents — they're still made in China! — it’s time to RUN, not walk, to the alternative choices. You’ve put this off for years; the time has come. There are a number of great alternatives to consider:

Universal Flux Remover (#MCC-UFR)
No-Clean Flux Remover – VeriClean™ (#MCC-DC1)
Lead-Free Flux Remover – Powerclean™ (#MCC-PW2)
General Purpose Flux Remover (#MCC-FRC)

Contact MicroCare for more details and suggestions.

SuprClean™ is a powerful, HFC-based fluid used for traditional (RMA) fluxes, solder pastes, plus oils, grease, some inks and acrylic conformal coatings

Question 52

Which Cleaners Can be Used in California?

Accepted Answer

California has some of the most restrictive air quality regulations in the world. Not only are they different from the rest of the U.S., they vary from city to city within California. It’s a challenge keeping up with it all.

We use several sources of regulatory information. One is the California Air Resources Board (“CARB”) which has the challenge to promote and protect public health and the environment through the reduction of air pollutants while recognizing and considering the effects of such reductions upon the economy of the state. Another good source is a regional regulatory body, the South Coast Air Quality Management District (“SCAQMD”), which has promulgated some of the most restrictive environmental regulations in the nation.

What’s the Problem?

The principle issue the regulators are working on is low-altitude smog. Much of the smog is caused by emissions of Volatile Organic Compounds (“VOC”). These chemicals react with sunlight to cause the brown haze for which California is so rightly famous. While car exhausts and power plants are far-and-away the biggest cause of VOC emissions, there is no doubt that organic solvents like IPA alcohol also contribute to the problem. As an industry, we have to do our part to help fix things.

Here’s an important point: under the policies of the South Coast Air Quality Management District, facilities are allowed to use VOC solvents as long as the quantity stays below certain thresholds. If you must use VOC solvents, use them with the TriggerGrip™ dispensing system (#MCC-ESD). This will dramatically reduce solvent consumption and help your facility stay below the emissions thresholds.

Low VOC Solvents

Probably the best choice for users in California is the new VOC-Free Flux Remover – UltraClean™ (#MCC-VOC). This is a new cleaner is based on a “siloxanes,” a material that is 100% VOC exempt and listed as the #1 Preferred Solvent Choice of the South Coast Air Quality Management District. Available exclusively through MicroCare, the solvent has superior toxicity ratings. A medium-strength defluxer, it also is very good on many adhesives and silicone conformal coatings. It is flammable, however, so it must be used with the same caution one would handle isopropyl alcohol.

The No-Clean Flux Remover – VeriClean™ is a another good choice for California. Also based on siloxanes, this cleaner is 93% VOC-exempt, which is excellent (but may no longer be good enough in certain locations). The solvent has superior toxicity ratings and is highly effective on most rosin-based and no-clean fluxes. It is flammable, so it must be used with caution.

Another excellent choice is the Universal Contact Cleaner. This nonflammable cleaner is based on proprietary HFO solvent technologies and is very gentle on the environment — ozone-safe, ultra-low global warming and zero VOCs. It is an excellent, safe and affordable aerosol light degreaser and medium-strength defluxer.

Lastly, for stencil cleaning we recommend the Aqueous Stencil Cleaner. This product replaces alcohol for stencil cleaning, eliminating a huge source of VOC emissions. This cleaner is water-based and with only a very small percentage of organics, so it offers excellent cleaning results with very low VOC emissions. This is a much, much better choice for stencil cleaning than IPA.

Local regulations vary around the globe. Every engineer should become familiar with the regulations which apply in your locality, and select the best solvent within those constraints.

The air quality in cities can be very poor, mostly due to VOC emissions in the atmosphere. This photo is Mexico City in 2010.

Question 53

What's a 'Wetting Index' and Why Is It Important In Cleaning?

Accepted Answer

A “wetting Index” is a measure of a fluid’s ability to clean complex shapes. Water has a very poor wetting index, which is a function of its inherent molecular structure while modern planet-friendly solvents do a much better job cleaning small, delicate or intricate shapes. Here’s why:

Aqueous or water-based cleaners have challenges that many engineers just did not anticipate. The basic chemical and physical properties of water are just not conducive to cleaning the complexity and miniaturization of a lot manufacturing processes today. The surface tension or “wettability” of water is the highest of any cleaning agent available, which means it will not clean well. As good chemists, we can add a surfactant to lower the surface tension. But even with surfactants, the surface tension will still be twice that of any solvent.

The viscosity of water and IPA also plays against good cleaning. Higher viscosities mean the solvent will not flow into tight spaces easily, and if you get the water into those nooks and crannies it probably won’t come out. That works against quality cleaning.

Water is heavy, but modern solvents are heavier — typically 20-30% heavier than water, and 50%+ heavier than alcohol. This means solvents can get under particulate, dissipate any static charge and lift particulate off the surface. Water lacks this capability and IPA is even worse.

Savvy engineers can combine all these factors into a scaleless index to compare the cleaning performance of different fluids. This score is called the “wetting index.” The higher the index the more likely the product will deliver excellent cleaning. Here’s a chart showing the wetting index of today’s popular cleaning choices:

Another factor in good cleaning is solubility, which normally is measured with pH for water-based cleaners and Kb value for solvents. Solvents can be tailored to have a wide range of Kb values, which gives them very versatile cleaning performance. Other factors include drying speed, aroma, toxicity, flammability and other concerns. Put it all together, and more often than not modern, planet-friendly solvents deliver better cleaning at lower cost.

(Note: For details about the mathematics behind a wetting index, contact MicroCare.)

Question 54

What Does 'Hygroscopic' Mean? Why Is It Important?

Accepted Answer

'Hygroscopic' is a chemical term which describes a behavior of certain chemicals. Hygroscopic chemicals absorb water; they love water. They want to pick up water molecules out of the air. Normal isopropyl alcohol (IPA, or rubbing alcohol) is infinitely hygroscopic.

Why is that important? Because solvents which carry water as a contaminant generally are weaker and less effective cleaners than solvents without water. Since people use alcohol on the workbench for touch-up cleaning, storing the alcohol in open jars, the alcohol will absorb water from the air and self-contaminate, especially if loosely-sealed. Later, when a technician tries to use the solvent again, he will find it doesn't work as well as it did before it became contaminated. In effect, hygroscopic solvents are self-diluting when exposed to air.

MicroCare makes a product, our Alcohol-Enhanced Flux Remover - ProClean™ (#MCC-PRO) that is a popular, alcohol-based solvent. When packaged, it is water-free to four decimal places — the purest, driest, most water-free alcohol we can find. These are typically called 'anhydrous' (water-free) or 'analytical grade' which is the highest, purest grade of alcohol. This costs a little more, but makes for a much better cleaner. This is also another reason why we highly recommend the TriggerGrip dispensing system, because the solvent is never exposed to air until the moment it is used.

Specific details about each product and water content can be found on this web site, on the product specification sheets, and in every safety data sheet, all available in this site.

Dip-and-brush cleaning allows the alcohol in the pump bottle to absorb water out of the air

Question 55

What Is a Kb Value? What Does It Tell Me About My Cleaning Fluid?

Accepted Answer

How well a fluid will clean depends on several variables including:

the contamination
the selected solvent
the application
the cleaning system
the physical shape of the parts being cleaned

When is pH a Good Enough Measure?

While the pH of a cleaning fluid can be a good indicator of a fluid’s cleaning strength, the pH test only works for fluids containing water. For non-aqueous fluids a better measure of cleaning effectiveness is the Kauri–Butanol (Kb) value.

pH measures the acidity or alkalinity of a fluid in comparison to water. The range goes from 0 – 14, with 7 being neutral. A pH lower than 7 indicates an acidic fluid which means it has more hydrogen ions than plain water) while a pH greater than 7 indicates a basic, or alkaline, fluid (more hydroxyl ions than standard water). Most aqueous cleaning systems use alkaline cleaning agents, often with pH ratings around 12-13. So for contamination that is water-soluble, looking at the pH makes sense.

Why Use the Kb Value?

Many types of contamination are not water-soluble. Non-aqueous solvents are a good choice for those cleaning jobs. Cleaing fluids are neither acidic nor alkaline; the pH test simply isn’t relevant because solvents don’t contain any water. That’s when the Kb value is your best guide to how strong a cleaner is.

The cleaning strength or solvency of non-aqueous cleaners usually is measured by an industry benchmark called the Kari-Butanol test. It is an industry standardized ASTM test (Method D-1133) that calibrates the relative strength of a cleaning fluid by immersing a test material called butanol — a thick, rubbery, eraser-like gum — in the solvent for a certain period of time under controlled conditions (e.g., temperatures, pressures, etc.). The lab technician then measures the remaining gum to determine the quantity of material that was dissolved by the solvent. It’s simple, fast and easy. The result of the test is an index called the Kari-Butanol, or Kb value.

The working ranges of Kb values go from 10 (very mild) to 200 or even higher (very strong cleaning). For years, the Kb value has been used to judge the relative cleaning “power” of cleaning fluids used on electronics, metals, optics and elsewhere. The Kb value is usually reported on MicroCare product spec sheets as “Kb value.” A higher Kb value is better and means the cleaner is more aggressive or active. Mild cleaners have low scores in the tens and twenties; powerful cleaners like the old chlorinated solvents have ratings in the low hundreds. Soft, mild MicroCare cleaners like the Alcohol-Enhanced Flux Remover – ProClean™ have Kb values in the mid-30s. Stronger cleaners, like the Heavy Duty Flux Remover – SuprClean™, will have values of 75-130.

Even Kb Values Have Their Limits

While it is convenient to state that higher Kb values indicate a “stronger” cleaner, it is not that precise. There are many limitations to the Kb test. For example, the test must be performed at 25°C (77°F) and one atmosphere pressure. Conducting the test under other conditions yields different results.

There are some solvents that cannot be evaluated using the Kb method since they dissolve the kauri gum almost instantly. Also, the original Kb test calibrated petroleum products but now it has been stretched to measure brominated, fluorinated, chlorinated, and other liquids. In other words, people are asking for the Kb test to deliver more than it can consistently provide.

Using Kb Values to Guide Cleaning of Fluxes, Oils and Grease

There is a general relation between the Kb value of a cleaning fluid and its capacity to clean fluxes, oils and grease. At MicroCare, our product specifications for cleaning fluids always include a Kb value to help you decide on the best solvents for the job you’re facing. Cleaning fluids with lower Kb values will dissolve greases but may not handle ionics and fluxes. Cleaning fluids with higher Kb values may be speedy and effective flux removers but attack plastic components or remove inks. Selecting a cleaner with the optimal Kb value is a balancing act. There are trade-offs. Many factors affect cleaning performance as well:

surface tension and density affect wetting
toxicity and flammability affect the handling of a material
costs certainly drive the economic analysis.

The Kb value is a handy benchmark and a good starting point for an analysis. A Kb number — like a pH value — is only a the first of many predictors of cleaning performance. In addition to the Kari-Butanol test, many engineers are also using systematic procedures to rigorously test cleaning fluids on their components, their contamination and their cleaning processes. This makes sense because it’s a test of real-world conditions. Often, the results are unexpected: the relatively mild fluids clean as well as or even better than cleaners with much higher Kb values. Informally, we call these surprising results “operational Kb values.” In these real-world cleaning of oils and fluxes, many MicroCare fluids clean much more effectively than the Kari-Butanol test would suggest while maintaining excellent materials compatibility. Special Note: You cannot compute a Kb value for a water-based cleaner, and you cannot compute a pH value for a solvent cleaner. Aqueous cleaners are profiled using the pH test for acidity or alkalinity. Different chemistries require different tools.

Special Note: The benchmark resin actually is the sap from the kauri tree (Agathis Australis) that only grows in New Zealand. Chemists searched for a solvent to liquefy that resin to make it useful industrially. They found that the gum was easily dissolved in butyl alcohol, so that became the benchmark solvent and is the source of the name of the test, the Kauri-Butanol test.

Question 56

What Is a Toxicity Rating (PEL, TLV, AEL)? Which Solvent Is the Safest (Has the Least Toxicity)?

Accepted Answer

At MicroCare, nothing is more important than safety. An important part of a strong safety program is understanding “toxicity ratings” for chemicals. This FAQ explains toxicity ratings and suggests how savvy engineers can use this information to improve safety in their facility.

What is a Good Score?

In the solvent world, chemists measure chemical safety in terms of toxicity ratings. These usually are called TLV (“Threshold Limit Value”, PEL (“Personal Exposure Limit”), AEL (“Assigned Exposure Limit”) or similar terms. These terms are generally (but not exactly) synonymous, and these rating systems work in the same general manner.

Note that these ratings are different from the popular NFPA ratings often found in the USA. Toxicity ratings are expressed in parts per million of chemical exposure. Like bowling, a high score is better and safer. It means you can be exposed to more of the chemical without any adverse effect. The scores are designed to estimate worker risk from exposure to the liquid for eight hours per day, five days a week, for a hypothetical thirty-year working career. A lower score means even a brief exposure to the cleaner may pose health hazards. A relatively hazardous liquid might have a TLV of 5 or 10 ppm. A safe fluid would be 400 ppm or higher. The highest possible rating is 1,000 ppm.

Field tests at MicroCare have shown that uncontrolled aerosol users are exposed to 75 ppm in normal use. TriggerGrip™ users and vapor degreaser users generally are exposed to 10-15 ppm.

MicroCare Uses Independent Toxicity Ratings

The best quality ratings are assigned by an independent safety organization ACGIH. Their toxicity ratings are based on data derived from very systematic testing protocols on animals. The actual lab results are then adjusted by trained hygienists and toxicologists to simulate a constant exposure to the solvent for hypothetical working career.

There are different types of TLVs, as well. MicroCare and most of the industry use “8-hour Time-Weighted Average” exposure ratings. There are longer and shorter and even instantaneous TLVs. Most of those are not relevant to cleaning fluids.

A “Rule of Thumb” About Toxicity Ratings

There is a good rule of thumb about TLV ratings. Toxicity ratings of over 400 ppm would be generally safe under most industrial situations. Isopropyl alcohol, also called rubbing alcohol, is a good benchmark. Super-pure, anhydrous IPA is available from MicroCare as the IPA-Based Flux Remover – IsoClean™ (#MCC-BAC) . It has a TLV of 400 ppm and a familiar aroma. While it is not a very powerful cleaner, it certainly isn’t going to make anyone sick.

Ratings from 100-400 ppm should require the product to be managed carefully. Ratings under 50 ppm are generally “pushing the envelope” and those chemicals should be used with caution.

It goes without saying that “toxicity” is NOT a perfect description of safety. Other important factors, such as flammability, storage, handling and disposal, need to be included in any safety analysis. Before selecting a solvent, contact a safety expert if you are unfamiliar with these issues and worried about the implications. Whenever the data is available, MicroCare uses ACGIH toxicity ratings. When that data is not available, MicroCare uses the toxicity ratings assigned by the solvent manufacturer. If that is not available, MicroCare lists all the toxicity data on the ingredients of each solvent within the MSDS sheet.

Good Solvent Choices with High TLV Ratings

If you like alcohol cleaning, we recommend Alcohol-Enhanced Flux Remover – ProClean™ (#MCC-PRO) which is a blend of three alcohols. It offers stronger cleaning than IPA with an improved safety rating of 568 ppm.

The No-Clean Flux Remover – VeriClean™ (#MCC-DC1) has a TLV of 200 ppm which sounds a bit on the low side, but in this case the TLV doesn’t tell the whole story. VeriClean™ is a remarkable solvent, based on siloxanes, and it is highly effective on most “no clean” fluxes and pastes. It is unique in that the raw material is quartz, also known as sand. (Yep, we mean S-A-N-D, as in high tide, sunburn and beach blanket bingo.) As for safety, the SDS sheet for the raw material says “No first aid should be required.” You don’t get much safer than that.

The nonflammable choices improve on worker safety even more. Choices like the General Purpose Flux Remover (#MCC-FRC), Heavy Duty Flux Remover – SuprClean™ (#MCC- SPR), the Lead-Free Flux Remover – PowerClean™ (#MCC-PW2) and so on) have very good toxicity ratings. Most of them have assigned TLV ratings in the range of 200 ppm. But in addition to being relatively safe they also are nonflammable. They dry quickly, have very little odor, have excellent materials compatibility profiles and some of them are azeotropes and so they can be used in heated cleaning systems.

Recommendations

Specific details about each product and its toxicity ratings can be found on every product specification sheet and in every safety data sheet (SDS) as published in this site.

MicroCare also recommends companies improve safety by improving the cleaning processes. This means to create a workplace environment where people use less solvent. MicroCare recommends using the TriggerGrip™ dispenser. in detailed field trials, the TriggerGrip™ dispensing system kept solvent vapors down to about 15 ppm, which improves worker safety. With the TriggerGrip™ dispensing system you will always use less solvent, get less on your hands, less in your lungs and less in your eyes. In this case, less is more — much, much more.

Question 57

What is an Azeotrope? Why Are They Important?

Accepted Answer

Many of the MicroCare cleaning products are azeotropes, and that's important because it lowers your costs, boosts cleaning effectiveness and enhances worker safety — all very good things. So the next question is, how does an azeotrope do that? For that answer, we have to go back to Chemistry 101.

Azeotropes Explained

An azeotrope is best described as “a constant boiling blend.” To be an azeotrope, the material has to be a mixture or a blend of at least two different compounds. For demonstration purposes, let's suppose we test an unscientific mixture that is 95% water and 5% ethanol.

Now let’s consider the boiling point of these materials. The boiling point of water is about 100 degrees Celsius.
But when we add that precise amount of 5% ethanol, the boiling temperature suddenly drops. This is very odd and unexpected. The two chemicals are still separate and distinct in the mixture, but when mixed together they jointly lower their combined boiling point.

Most importantly, as an azeotropic mix, the two constituents will boil off at the same rate. If we boil the mixture in a beaker and measure the fumes coming off the boiling liquid, we would notice that the mixture of the ingredients is still at the same 95:5 ratio. When we chill those fumes and condense the material back into a liquid state it again will have the same 95:5 mixture ratio. In fact, no matter what we do, the mixture always stays at the 95:5 proportions. This means we have created an azeotrope. With azeotropes the ingredients never separate.

Watch a video on azeotropes here.

MicroCare Azeotropes

There is a bit of magic to making azeotropes. Not all liquids form azeotropes because the density, boiling point and surface tension all has to be exactly right. Finding a true azeotrope is very difficult, but the Critical Cleaning Chemists at MicroCare have formulated a number of them for vapor degreasing including:

Tergo™ XCF3 Superior Cleaning Fluid and Degreaser
Tergo™ CCA Braod Range Degreasing Fluid
Tergo™ PF105 High Purity & Ionic Static Remover
Tergo™ PF100-IPA IPA Based High Purity & Ionic Static Remover

Azeotrope Benefits

Azeotropic behavior allows engineers to deliver the benefits of a mixture with the convenient handling and storage of a single compound. There are three main benefits of azeotropes:

Perhaps the most important benefit of an azeotrope is the unexpected ability to mix flammable and nonflammable ingredients to produce a stable nonflammable mixture. This is an amazing chemical phenomenon. Imagine mixing flammable products — like IPA alcohol — into a non-flammble chemical and yet still retain the convenient handling of a nonflammable chemical. In contrast, if a product is merely a mix of chemicals, when there is a spill of the solvent on the factory floor some flammable chemicals may evaporate faster than other chemicals, creating a cloud of flammable vapors above the spill. This is so important for safety that the process is simulated during the 'Tag Closed Cup' flammability test.
Another benefit of azeotropes is that they are very easy to distill and recover. If the solvent in a vapor degreaser is an azeotrope, then the solvent can be boiled and recycled. Meanwhile, while the contamination -- the non-azeotropic stuff mixed into the solvent, such as fluxes, oils, water, and such -- stay 'trapped' at the bottom of the machine. In effect, using azeotropic solvents allows us to trap and concentrate the contamination using distillation instead of using filters and membranes and such.
Lastly, azeotropes permit the 'tweaking' of a blend to obtain unique physical properties which makes the blends useful across a broad range of applications. For example, if you have a very mild cleaner, but add some other ingredients in azeotropic proportions, you can make a blend that is a very strong cleaner, or safe to use or really inexpensive. In other words, azeotropes allow us to customize cleaning fluids to fit almost any application or budget. The possibilities are almost limitless.

About Near-Azeotropes and Co-Solvents

Sadly, not all azeotropes are created equal. To a finicky chemist, a perfect “true” azeotrope only exists at a single temperature and specific pressure where the azeotropic behavior is observed. But “close” can be good enough. Many products are successfully marketed today which are not “perfect azeotropes” but near-azeotropes.

Near-azeotropes, also known as "azeotrope-like", can be repeatedly evaporated, condensed, and recycled without changing the blend’s composition or other properties. Even though it is technically just a mixture of different chemicals and does not meet the exact technical description of an azeotrope, a near-azeotropic solvent behaves as if it were a single pure component solvent rather than a solvent mixture. These cleaners are so close to being azeotropes that they exhibit stable azeotropic behavior.

These cleaners are not perfect azeotropes in the strictest definition of the word, but offer azeotrope-like stability and can deliver the performance, safety and time-saving convenience of single-solvent operations under almost all conditions. Some popular examples of near-azeotropes or azeotrope-like cleaning fluids include:

Tergo™ GCF General Cleaning Fluid
Tergo™ SFR Flux and Ionics Cleaning Fluid
Tergo™ XCF2 Specialty Cleaning Fluid, Flux Remover and Degreaser
Tergo™ HDF Heavy Degreasing Fluid
Opteon™ SF80 Specialty Cleaning Fluid

Co-Solvent Cleaning Fluids

Lastly, sometimes there is no single solvent or azeotrope which is sufficiently strong to get the job done. In this case, some customers switch to using a bi-solvent or a co-solvent system. These systems use two solvents — one aggressive cleaning solvent, and one milder rinsing — to remove the most difficult soils. The Tergo™ Chlorine-Free Cleaning Fluid is one such co-solvent product. For more details about co-solvents, contact MicroCare.

Question 58

Are There Any IPA Replacement Cleaners?

Accepted Answer

IPA (Isopropyl Alcohol) replacement cleaners are in high demand. Due to the COVID-19 outbreak, IPA for electronics cleaning is in very short supply. Since everyone from the medical industry to electronics manufacturers is using IPA for cleaning, it it quickly becoming a rare commodity. Many companies are now facing IPA shortages. Fortunately, MicroCare offers excellent alternatives to IPA for cleaning PCBs and other electronics. Many of the IPA replacement cleaners for electronics actually clean better than IPA and are safer to use.

Some of the IPA alternatives include:

See the IPA Replacement Cleaning Products Flyer here.

IPA Replacement Cleaning Products Flyer

Question 59

How Do I Choose a Contact Cleaner?

Accepted Answer

Electrical Contact Cleaners dissolve oils, remove dirt and other particulates and refresh electrical connectivity on relays, switches and other devices. They safely remove grit from hot motors and dust from inside electromechanical relays and keyboards. They are also effective at removing contaminants from hard-to-reach areas on electrical connectors, power supplies, junction boxes and distribution panels. The perfect contact cleaner should be nonflammable, noncorrosive, and have strong dielectric properties. Ideally, it could even be sprayed on energized electrical circuits without concern. It is also very important that the cleaning agent is safe for use on all component materials without the risk of damaging any delicate parts.

Know Your Materials

Although the capability of the contact cleaner is important, so is its compatibility with the parts being cleaned. When it comes to choosing the correct contact cleaner, first check for material compatibility. Does the device consist of just one type of material or is it made up of several materials with vulnerable components? Perhaps it has an LCD display made from transparent polycarbonate, contains inks, or includes rubber parts that may be damaged by aggressive solvents? If you are unsure about the materials of construction, it is important to test the contact cleaner for materials compatibility before the extensive use of the cleaner.

Keep the Kb Value Low

Quite often a strong contact cleaner is used to ensure cleanliness. It can deliver excellent results and clean quickly. However, if an electronic device is made from a variety of materials, and in particular includes plastic components, it is better to use a contact cleaner with a low Kauri Butanol (Kb) value. Too-strong contact cleaners may dissolve, craze or attack softer substrates; therefore, a milder plastic-safe cleaner is preferred. A contact cleaner with a Kb value of between 15-40 indicates that the contact cleaner is mild and suitable for most surfaces. Kb values can be found on the contact cleaner’s technical data sheet.

Test the Cleaner

To ensure the contact cleaner can be used without affecting materials you should conduct a ‘cleaning trial’ on a sacrificial or test part. Start with a mild cleaner first and progressively try stronger cleaners until the optimal cleaning result is achieved. Be sure to perform the testing in more than one area on the part to ensure it is safe for all the materials the cleaner may contact, either directly or indirectly. You can conduct your own in-house cleaning trials or MicroCare can conduct an in-lab cleaning assessment on some of your sacrificial test parts. The lab will conduct cleaning trials on your specific parts and contamination to ensure effective cleaning with the fewest risks to the parts.

Universal Contact Cleaner

Question 60

What are the Benefits of Better Quality Stencil Rolls?

Accepted Answer

Many customers think of stencil rolls ascommodities. They want the cheapest stencil roll they can get because they think there is no difference between the brands. However, there IS a difference in rolls, and cheap rolls can turn out to be very expensive.

Stencil printing is far more complex than many people think. There are over three dozen different stencil printing parameters that must be optimized on an SMT printer. Because of this complexity, the typical SMT line only runs at 90-95% yield. With proper stencil printing, SMT lines can run at 99%+ yields.

The key to better printing is to stop using alcohol during stencil cleaning. The alcohol leaves residue on the stencil that mixes with the solder paste and change its viscosity, resulting in a bad print. By eliminating the alcohol and only dry-wiping, it allows for faster production, higher throughput, higher yields, less scrap, less rework and fewer warranty claims, making your company more profitable and competitive.

However, most stencil rolls need to wipe wet because the paper is weak and leaves lint. A better answer is to use a stronger, cleaner stencil roll material that doesn’t need alcohol. Choose a better quality paper roll or opt for a fabric roll. They are stronger, more absorbent and can effectively dry clean stencils without leaving fibers or solder balls in the apertures. Using higher quality rolls help produce better-quality boards requiring very little rework.

Although the higher quality rolls cost more, many manufacturers are finding that they are wasting less time cleaning and spending more time printing, boosting throughput and productivity.

Benefits of Using Better Quality Stencil Rolls:

Increases productivity: At a major PCB subcontractor, better quality rolls boosted production from 32 to 55 boards per hour – a 60% increase in productivity.
Higher Yields: In a large-scale trial with five SMT lines switching to better quality rolls pushed the defect-free yield to 99.55% from an average of 97.25% — an 83% reduction in defects.
Reduces defects: A large subcontractor in Europe found that improved rolls eliminated 35% of their SMT defects at functional test.
Eliminates rework: A manufacturer in China made more than 2,000 boards without a single defect.

Question 61

My StatZap™ No Longer Fits on My Micro•Blast™ or Big•Blast™ -- What's Up With That?

Accepted Answer

The StatZap™ ESD (Electrostatic Discharge) Eliminator is a small tool that fits on most MicroCare aerosol cans and replaces the red plastic spray tube often used on aerosol sprays. The StatZAP™ reduces the static charge produced by fast-moving liquids to a harmless 50 volts. Made from aluminum and stainless steel, the StatZAP™ is probably the best $6 insurance policy money can buy.

However, someof the precision dusters from MicroCare are not compatible with the StatZap™. The General Purpose Dust Remover (#MCC-DST and -DST14A) is equipped with new, high-pressure spray valves. This new valve gives these products more “pushing power” to blow dust and lint from hard-to-reach places. But, these new valves are not compatible with the StatZap™ tool.

The StatZap™-compatible valve is solid white plastic (see photo, right). The new high-pressure valve is translucent plastic with three small vents on each side.

If you want dusters with the StatZap™, simply order the product with the old, tradition, StatZap- compatible valve. The part numbers for the StatZAP™ compatible valve are MCC-DSTZ and -AIRZ for General Purpose Dust Remover.

Both versions of the freeze spray products (the regular version and the ‘anti-stat’ version) are compatible with the StatZap™.

The TriggerGrip™ cleaning tool also is ESD-safe and eliminates static when cleaning during rework and repair.

The StatZAP™ is a handy tool that reduces the risk of electrostatic damage to PCBs

Question 62

What Can I Use to Clean Computer  Keyboards, Cabinets and Housings?

Accepted Answer

There are many different types of contamination which need to be removed simultaneously. First, we have to get dry contamination out from hard-to-reach areas, like dust and lint from deep inside your keyboard. Secondly, we have to remove oily fingerprints, tape residues and grime from the housings and cabinetry. As you might expect, there are several great answers for this problem.

The Universal Contact Cleaner (#MCC-CCH10A) is a nonflammable, fast-drying choice for washing contamination from switches, relays and hard to reach places. It has the best environmental characteristics of any cleaning solvent on the market today.

MicroCare also offers precision dust removers in several different sizes and two different formulations. The General Purpose Dust Remover is the best choice for lint in keyboards, CD drives and other delicate equipment, as well as simple dusty contamination. This economy-sized 400 gram canister is loaded with an ultra-pure gas, filtered to 0.2 microns. Blast it the keyboard or disk drive, and the dust goes flying. Ozone-safe, nonflammable, zero VOC content.

The TidyPen® Adhesive Remover also is helpful around offices and labs, removing tape residues quickly, easily and inexpensively.

Question 63

How Can I Remove Toner Off Laser Printers and Copiers?

Accepted Answer

The best cleaner for toner is (or perhaps we should say, “was”) the old-style solvent called 1,1,1-trichloroethane, also known as TCA. It just lifted toner away marvelously. But, since 1,1,1 is an ozone-depleting solvent, you’re not going to find much of it around any more.

As a replacement, try Stencil, Squeegee and Misprint Cleaner – ScreenClean™ (#MCC-CDI). It was formulated as an ink remover. It is excellent for cleaning the inside of printers and is generally plastic-safe. It dries slowly which gives you longer tack-time for cleaning. It is not quite as good on toner as 1,1,1-TCA used to be, but they’re better than anything else we have found so far.

ScreenClean™ is available in presaturated wipes and in bulk packaging (one gallon/3.9 liters; five gallons/nineteen liters, and 55 gallons/200 liters).

The MicroCare Stencil, Squeegee and Misprint Cleaner is packaged as a presaturated wipe

Question 64

Which Is the Best SMT Stencil Cleaner?

Accepted Answer

When it comes to SMT stencil cleaning, the best results come from nonflammable, slower-drying fluids working with lint-free fabric wipes (no paper with cellulose and glues) to get perfect results. Detailed results depend on the solder paste being used, the age of that paste, the design of the stencil and how it was made, whether you are applying it manually or in an automated system, how often you need to clean and the way you want to clean. It also depends on if you additionally want clean misprinted boards, or the epoxy dispensing systems, or the machinery itself.

Here are a few recommendations —

For simple, manual stencil cleaning our recommendation would be to use the Aqueous Stencil Cleaner (#MCC-BGA). Nonflammable, nontoxic and highly affordable, this cleaner vastly out-performs alcohol. One of our most reliable products, this Stencil Cleaner will never let you down. It removes even dried, hardened paste from the tiniest of apertures. It’s a great stencil cleaning choice and money-saving refills are available.

If your preference is for presaturated wipes, use the MultiTask™ Economy Surface and Stencil Wipes (#MCC-MLCW). Our unique “slam shut” lid makes one-handed cleaning easy, and ensures the tubs won’t dry out while waiting for the next cleaning event. These are the ONLY wipes in the industry without a shelf life and the ONLY wipes in the industry that use money-saving, planet-saving refills.

For stronger cleaning in a presaturated wipe, jump to the Uncured Epoxy Remover (#MCC-EPX) or the Stencil, Squeegee and Misprint Cleaner (#MCC-CDIW). As the names suggest, these are more powerful solvents to help remove more difficult contamination, like uncured chip bonders.

In any case, check out MicroCare’s broad selection of understencil wiping rolls and our huge array of lint-free wipes to use on the stencils you’re cleaning.

Part Number	PFR10A
Package	Aerosol
Weight	0.3 kg 0.66 lb.
Size	310 ml 10.5 oz.
Technical Data Sheet	TDS
Safety Data Sheet	SDS

Appearance	Clear, colorless
Odor	Acetone
PEL (ppm, 8-hr TWA)	50
Boiling Point	55ºC / 131ºF
Chemical Family	Organic Solvents
F-Gas Compliant
Evaporation Rate	Slow
Cleaning Strength (Kb)	72
Active Ingredients	Acetone, alcohols
Flashpoint	Not Available
Global Warming Rating (100yr)	Not available
VOC Organic Content (g/L)	184
Ozone Impact	0
REACH & ELINCS Compliant
RoHS & WEEE Compliant
Safety Rating	Flammable
Specific Gravity	0.75 g/mL

Polar Flux Remover

Product Information

Applications:

Features:

Product Details

Safety Data Sheet

AEROSOL

BULK

Technical Data Sheet

Electronics