“Normal Propyl Bromide” (nPB) is the full chemical name for the active ingredient in the Bromothane™ solvents. It also can be called 1-bromopropane or 1-propyl bromide, and is a colorless, nonflammable organic cleaning fluid engineered to be used in vapor degreasers. It has the chemical formula C3H7Br and the CAS number 106-94-5. Based on the element bromine, nPB is a unique liquid selected by MicroCare and Chemtura to be the cornerstone upon which the Bromothane™ family of cleaners is built.
Bromine is a halogenated material. It is related chemically to the other halogens, which means they are all in the same column on the periodic table of the elements (if you’re interested, see col. 17 on the right-hand side of the Table). Other halogens include chlorine, fluorine and iodine, all of which are widely used as cleaning products. nPB is a great replacement for the chlorinated solvents like perc and TCE, the old CFC cleaners, and more modern ozone-depleting hydrochlorofluorocarbons like HCFC-141b and HCFC-225, and the fully-fluorinated materials (PFCs).
Vertrel® is the brand name for a family of ozone-safe solvents made by the DuPont Company for precision cleaning. Specifically, the term Vertrel® describes a group of fluorinated solvents and specialty fluids. At their core, each product is based on HFC-43-10mee which is also known as 2,3-dihydrodecafluoropentane; the chemical formula for the material is C5H2F10 and the CAS Number is 138495-42-8. It is a clear, colorless liquid with “zero” ozone depletion and low global warming potential.
Unique physical properties of HFC-43-10 include a high density, low viscosity and low surface tension. These attributes, combined with its nonflammability, chemical and thermal stability, low toxicity, and ease of recovery by distillation, make HFC-43-10mee ideal for a broad range of applications including vapor degreasing and cold-wiping.
By itself, it is a very mild solvent, but the solvency can easily be enhanced by use of appropriate azeotropes of alcohols, hydrocarbons, esters, etc. Most of the commercial products also contain other ingredients, such as alcohols, trans-1,2 dichloroethylene, and/or HFC-365, which tailor the solvent’s performance to specific cleaning requirements. All but two of the Vertrel® products are true azeotropes or exhibit azeotropic-like behavior, which means they can be used repeatedly and safely in heated cleaning systems.
Today’s electronics are often cleaned with either (a) MicroCare CMS defluxer, (b) DuPont™ Vertrel® SFR flux remover, or (c) Bromothane™ R. Each has different benefits and weaknesses; see the product specs for details.
The MicroCare fluids easily dissolve all types of oils, lubricants and even light greases. Once the oil is dissolved in the cleaning fluid, the oil will be removed from the parts and trapped in the “boil sump” of the vapor degreaser where it can be easily cleaned out during routine maintenance. The parts come out clean, dry and at room temperature.
Another common chore for MicroCare fluids is displacement cleaning. In this application, the specific gravity of the MicroCare fluids and the very low surface tension of the solvent deliver cleaning results simply not possible with aqueous or hydrocarbon cleaners. The addition of an alcohol or other polar solvent to a formulation is also very helpful in removing particulates from non-conductive surfaces such as plastics. The polar solvent makes the formulation more electrically conductive and helps wickaway static charges which cause particulates to adhere to the surface.
For these applications, MicroCare normally recommends MicroCare CCA degreaser, DuPont™ Vertrel® SDG, or Bromothane™ R. These are highly polar, extremely dense solvents. They will flush the contamination away in a manner that aqueous cleaners simply cannot match. See the Product Specifications for details.
Using a MicroCare cleaner to remove excess water after an aqueous or semi-aqueous pre-cleaning process is a great “one-two” punch. This is technically called “solvent drying.” If there is only a small amount of water to remove, DuPont™ Vertel® XP or MicroCare® CFIPA are good choices. Drying with these types of products is called absorption drying because the polar components in these products absorb the water on the parts. For applications with large amounts of water, DuPont Vertrel® XDA/XFA is an excellent combination. These products are used in a process called displacement drying. The additives in these products cause water to bead up and float to the surface of the immersion sump. See the Product Specifications for details; also visit the Learning Center.
This is another application that showcases the versatility of the MicroCare products. When components are dipped into the bath containing the coating, diluted in the MicroCare fluid, the coating goes on smoothly and evenly across the surface on the part. Drips and runs are minimized because the MicroCare fluids evaporate quickly as the part is removed from the bath. It’s a fast, simple and highly effective process.
MicroCare CF is the most commonly used carrier agent for PTFE coatings because both PTFE and the MicroCare fluids are based on fluorine, so they work well together. The Bromothane™ fluids are better for silicone coatings and lubricants and can be dissolved in concentrations up to 15% or so. See the Product Specifications for details.
MicroCare produces a family of PTFE coatings pre-mixed and ready-for-use. These are marketed under the "DuraGlide™" name. For more details, visit the MicroCare Medical web site.
Many of the MicroCare cleaners are used on newer military applications but not for the very oldest mil specs. In the 1990s the military, in conjunction with the I.P.C., developed MIL-STD-2000 as a performance-based cleaning specification for military applications. In effect, MIL-STD-2000 allowed the manufacturer to use any solvent they wanted provided the manufacturer could prove the new cleaning method was at least as good as the old cleaning method. Today, virtually all cleaning is done to these new standards (with the exception of a very few old military and nuclear projects). Contact MicroCare for more details.
For hand-dipping or hand-wiping application, use MicroCare HDS precision degreaser. Many MicroCare cleaners also are available in aerosol and pump sprays; visit the MicroCare web site for details on those products. In general, the Bromothane™ solvents are not suitable for hand-wipe applications because the worker exposure would jump far over the recommended safety level of 10 ppm.
Usually, yes. MicroCare packages a wide variety of the cleaning fluids into aerosol packages. For more details about the specific products and where their applications, visit the MicroCare web site.
However, MicroCare feels strongly that while the Bromothane™ family of cleaners are very safe when properly used in engineered systems which minimize worker exposures, aerosols are prone to abuse and will subject workers to exposures in excess of the recommended Bromothane™ exposure limits of 10 ppm. So the Bromothane™ cleaners are not available in aerosol.
Absolutely. There are many different blends and mixtures of the MicroCare cleaners and the Bromothane™ in the MicroCare labs. Many are just sitting on the shelf waiting for the right application. We have a wide array of options already on the market (which will save you money) but if you need something extra special we have a proven track record of delivering custom blends, as well. Contact MicroCare for details.
There is no doubt that many companies will continue to take a long, hard look at the “traditional” chlorinated solvents such as trichloroethylene (“trike” or “TCE”), methylene chloride and perchloroethylene (“perc”). Their main appeal is that they are far, far less expensive than more modern solvent choices.
But there are problems. Traditional chlorinated solvents may be incompatible with many of the modern elastomers and plastics. There is a concern over the toxicity and environmental safety of many of the cleaners. All are regulated as NESHAP pollutants and can only be used in totally contained equipment. Any facility using them will need stringent air quality testing procedures or other risk-management controls.
In contrast, the MicroCare cleaners and the Vertrel® products have a much higher (safer) AEL of around 200 ppm. The MicroCare Cleaners are not NESHAP-regulated so they can be used in less expensive vapor degreasing equipment. The list goes on and on: if you have tough cleaning problems, then the MicroCare cleaners and specialty fluids are the choice for you.
In general, when comparing a vapor degreaser with a comparable aqueous, semi-aqueous, or hydrocarbon cleaning system, those types of cleaning systems will tend to be much larger than the vapor degreaser, more complex than the vapor degreaser to operate and maintain, be more expensive to operate and maintain than the vapor degreaser, consume more energy than the vapor degreaser, and clean more slowly than a similarly-sized vapor degreaser (slower through-put).
For more details, visit the Learning Center.
In general (and this is a large generalization) the old-style chlorinated solvents were used for the toughest cleaning applications. In that sense, the Bromothane™ products are an excellent, almost-drop-in replacement, and will provide safe, effective and environmentally acceptable alternatives to the old-style, chlorine-based solvents. Specifically, the Bromothane™ cleaners are an excellent replacement for many solvents such as trichloroethylene (TCE or “trike”), trichloroethane (TCA or“1-1-1”) and perchloroethane (“perc”). Properly used, Bromothane™ will deliver faster, better and cheaper cleaning than any equivalent alternative on the market today.
In addition, several of the DuPont Vertel® and MicroCare cleaning fluids, including MicroCare CMS, MicroCare HDS and DuPont Vertel® SDG usually can handle these applications. Contact your MicroCare representative for more guidance.
The MicroCare products and the DuPont Vertrel® solvents meet and exceed the performance of HCFC-141b in almost every cleaning application. The new cleaners generally have superior materials compatibility to HCFC-141b, slightly higher boiling points than HCFC-141b, and they are completely ozone-safe. In fact, all of the MicroCare cleaners are SNAP-approved as replacements for HCFC-141b.
The Bromothane™ materials have a materials compatibility that is almost identical to HCFC-141b and they work in the same equipment used with HCFC-141b. But the Bromothane™ solvents have a toxicity rating of 10 ppm. Because of this, Bromothane™ solvents are only sold for applications using engineered systems – no dipping, wiping, cold cleaning or aerosol sprays are permitted. If those types of applications are required, switch to the MicroCare aerosol cleaners.
HCFC-225 is no longer a great choice for most cleaning applications. First and foremost, HCFC-225 is being phased-out in 2015 because it is an ozone-depleting substance. Specifically, it is a Class II Ozone-Depleting Substance under the U.S. Clean Air Act. It’s already banned in Europe. In addition, HCFC-225 is has a fairly limited product line with just a few azeotropes to chose from. HCFC-225 also has some toxicity worries due to one of the HCFC-225 isomers which is substantially more toxic than the other (although it normally is present in the solvent at very low levels).
All of the MicroCare precision cleaners, all of the Bromothane™ blends, and most of the DuPont Vertrel® products are azeotropes. This is important because it lowers your costs, boosts cleaning effectiveness and enhances worker safety. Azeotropic behavior delivers the benefits of a chemical mixture with the convenient handling and storage of a single compound.
For example, azeotropes are very easy to distill and recover. Another important benefit of an azeotrope is the unexpected ability to mix flammable and nonflammable ingredients to produce a stable nonflammable mixture. Lastly, azeotropes permit the “tweaking” of a blend to obtain unique physical behavior (aggressiveness, temperature range, etc.) that makes the blends more useful across a broader range of applications.
Check each product specification or the Learning Center for more details.
The cleaning power of a solvent usually is measured by an industry benchmark called the Kari-Butanol test. This is usually reported on product spec sheets as a Kb value. Higher is better and means the fluid is a stronger, more aggressive cleaner. Mild cleaners have low scores in the tens and twenties; powerful cleaners like the old chlorinated solvents have ratings in the low hundreds.
The MicroCare and Vertrel precision cleaners have Kb values ranging from 20 to 70. The Bromothane™ solvents have Kb values near 125. See the product specifications for details or the Learning Center for a general overview of cleaning.
The MicroCare cleaners are the best choice for precision cleaning of difficult shapes and awkward pieces. The reason for this success is the inherent chemical characteristics of the liquids:
- A low surface tension means the solvent can get into tight spaces more easily than solvents with high surface tensions (like aqueous systems).
- A dense, heavy solvent literally can float away contamination that other types of cleaning agents cannot move.
- And a solvent with low viscosity flows in and around objects more effectively than solvents with high viscosity (think molasses, or maple syrup).
A clever way to combine all these different measurements is to unify them into a single index, called the wetting index. The formula for computing the wetting index is:
Wetting Index = (Density x 1000)/( Surface Tension x Viscosity)
The wetting index of alcohol is 15. The wetting index for the MicroCare cleaners is around 150. For more details, see the Learning Center.
No, you will not have an acidity problem with the MicroCare cleaners and the DuPont Vertrel® products. Since these products do not contain “free” halogens like chlorine they cannot turn acid. This means that the MicroCare cleaners and the DuPont Vertrel® productsare much safer and easier to handle than the old chlorinated solvents.
But Bromothane™ solvents can turn acid. This is prevented by testing the solvent and adding additional stabilizer. MicroCare sells BromoBooster™, a concentrated stabilizer that you add to the solvent from time time to time. A simple test kit is available from MicroCare contains everything you need to test the solvent and compute the quantity of booster to add. It takes about ten minutes once a week, and is as simple as being able to count drops falling from an eyedropper.
For more details, see the Learning Center.
The MicroCare cleaners and the Vertrel® products have excellent materials compatibility across almost all of the common materials of construction, including metals (zinc, stainless steel, carbon steel, aluminum and copper, for example), FR-4 substrates, fiber glass, resins, plastics, ceramics, glass and most elastomers. Some of the stronger blends have minor compatibility concerns with soft plastics, such as acrylics, ABS, and polycarbonate. Gaskets and elastomers will demonstrate some swelling and will, in most cases, revert to within a few percent of original size after drying. EPDM, butyl rubber, Buna-S, and neoprene are recommended for elastomeric parts.
The Bromothane™ solvents are much more aggressive but still have generally good materials compatibility. Bromothane™ products are compatible with zinc, stainless steel, carbon steel, aluminum and copper, plus fiber glass, resins, plastics, ceramic and glass. Under certain circumstances they may react with white metals. Bromothane™ products have compatibility issues with soft plastics such as polycarbonates and certain component, such as capacitors. Contact with highly basic process materials, pH 10 or above, is not recommended. Thorough testing prior to deployment is particularly important.
For more details, check the individual product spec sheets, or contact MicroCare.
Below is an abbreviated listing of the major vapor degreaser manufacturers. They are all good companies and make fine products:
Branson Ultrasonics – Connecticut
Contacts: Tel: 203-796-2298
On the web at www.BransonCleaning.com
DGB Sale, Inc. - Minnesota
Contact: David G Blackstone, Tel952-693-5526
Contact: Mr. James Jaworski Tel: 609-883-4000
On the web at www.crest-ultrasonics.com
Ultronics – Pennsylvania
Contacts: Carl Wolf, Tel: 800-553-7881
On the web at www.ultronix.com
Tiyoda-Serac – Rhode Island
Contacts: Bill McCormick, Tel: xxx-539-5471
On the web at: www.TIYODA.Com
UKI (Ultra-Kool, Inc.)– Pennsylvania
Contacts: Al Hartman, Sales Manager, Tel: (610) 367-2019, Fax: (610) 367-8396
On the web at: www.ultra-kool.com
The recommended maximum speed for work entry and removal from degreaser/defluxers is 10 ft/min. Higher throughput rates can cause vapor/air interfacial disturbances that result in high vapor losses.
Yes, you can and should recycle the MicroCare Cleaners. Every vapor degreaser is a recycling still, in addition to being a vapor cleaning system. That means that every vapor degreaser automatically recycles the solvent while it is operating.
In addition, there are companies with a thriving business in reclaiming solvents. They will pick up your exhausted solvent, distill it and purify it, and then re-sell it at a reduced cost. This was an excellent program because it allowed companies to re-use perfectly good solvent that otherwise would have been disposed.
If you need the name of a company that offers a solvent reclamation service, contact MicroCare.
A variety of drum pumps are available for transferring the contents of pails or drums of solvents to the point of use. MicroCare strongly recommends the use of drum pumps as a convenient way to empty a drum.
Drum pumps are small portable pumps inserted through the opened bung in the head of a drum or pail. During pumping, the drum rests on the floor in a vertical position. Drum pumps minimize both solvent losses through evaporation and worker exposure to solvent vapors, and provide a safer, more flexible and economical way of discharging drum contents.
The following companies can help you with drum pump selection:
625 East Bunker Court,
Vernon Hills, IL 60061
On the web at: www.coleparmer.com
Lab Safety Supply
P.O. Box 1368
Janesville, WI 53547
On the web at: www.labsafety.com
500 West 7th Street
Auburn, IN 46706
On the web at: www.riekepackaging.com
United States Plastic Corporation
1390 Neubrecht Road
Lima, OH 45801
On the web at: www.usplastic.com
Industrial Safety Company
1390 Neubrecht Road
Lima, OH 45801
On the web at: www.indlsafety.com
The MicroCare cleaners are shipped in drums which can weigh in excess of 600 lb./280 kilos. Moving such heavy objects is a serious undertaking and not to be attempted without the proper equipment, training and supervision. Whenever drums are handled, several cautions should be observed. Visit the Learning Center for more details.
Another important issue: while the MicroCare cleaners are extremely cost-effective, they are not cheap. When storing the drums, always double-check that the bungs are tightly sealed. This will minimize evaporation losses and save money.
The MicroCare fluids and the DuPont Vertrel fluids do have a global warming impact, although it is lower than older technologies. This means that these fluids are a safe, nonflammable, middle-of-the-road choice when compared to the major global warming chemicals (such as halogenated fire supressants and fully-fluorinated solvents like PFCs).
The Bromothane™ cleaners are not a major contributor to global warming. The current estimate of Bromothane’s GWP is zero (0). This is because the Bromothane solvents break down in sunlight in 16-19 days, so they never have time to affect the climate.
Details on the GWP of the MicroCare, Vertrel and Bromothane cleaners are on the Product Specifications.
Yes, most of them do contain at least some portion of VOCs. In general, the Bromothane™ cleaners are 100% VOCs. Most of the MicroCare and Vertrel fluids have some, lower VOC content. For the specific details for each product, see the individual Product Specifications available on this web site.
The MicroCare fluids and the DuPont Vertrel® specialty fluids are all completely ozone-safe and are ideal replacements for ozone-depleting solvents such as CFC-113, 1,1,1-trichloroethane, HCFC-141b and HCFC-225, as well as high-global-warming solvents such as perfluorocarbons (PFCs).
The Bromothane™ solvents are slight – VERY slight – ozone-depleting solvents but are not listed in the Montreal Protocol. So it is technically correct to say that nPB is not listed as a “Class II” ODS, the more precise truth is that nPB has a slight ozone-depletion potential. According to the EPA, at the latitude of the US, nPB has an ozone depletion potential (ODP) of 0.013 to 0.018.
There is a perception that water cleaning is “green” but to say “water is better” is to over-simplify a very complex issue. MicroCare cleaning fluids are easily recycled and distilled inside the same machine that does the cleaning; it’s an inherent part of the process. Aqueous cleaning systems need a lot of water, which is becoming scarce in some areas, and a lot of electricity, which is expensive and contributes to global warming. MicroCare cleaning fluids are ozone-safe and also are low in global warming potential.
For more details, visit the Learning Center.
The Montreal Protocol is an international treaty that specifies the phase-out of ozone-depleting substances. Developed in the 1980s, more than 100 nations worked together to set the rules for eliminating ozone-depleting substances around the globe.
All the MicroCare cleaners have their toxicity ratings listed prominently on the MSDS sheets. In general, the MicroCare cleaning products and the Dupont Vertrel® specialty fluids can be considered very safe for workers and relatively “non-toxic.” The Bromothane™ cleaners do have some special toxicity concerns and MicroCare has implemented a strong product stewardship program to manage those.
Specifically, DuPont has set the Threshold Limit Values (TLV) for the Vertrel® fluids to be around 200 parts per million (ppm) which is considered very safe. MicroCare uses similar ratings for the MicroCare-branded materials. All of the Bromothane™ products are classed at 10 parts per million.
The Threshold Limit Value (TLV) of 10 ppm for the Bromothane™ solvents is much lower than the ratings some companies use. MicroCare uses the Threshold Limit Value (TLV) for nPB that was established by the American Conference of Industrial Hygienists (ACGIH). This TLV applies to the Bromothane™ brand solvents sold by MicroCare and to all other versions on nPB marketed by other companies under other brand names.
The decision on the TLV of nPB was not without controversy. Other companies had urged higher threshold levels, as high as several hundred ppm. But MicroCare feels strongly that the ACGIH decision is the best standard to use.
For more details, see the Learning Center.
The vapors from the MicroCare cleaners are generally not hazardous, but monitoring the vapors is an important part of a company’s worker safety program. MicroCare requires an annual air quality monitoring program as part of the Bromothane™ product stewardship program. All Bromothane™ users are required to conduct a simple workplace exposure test using air monitoring badges to assure worker safety. This is an excellent process and is applicable to the other MicroCare cleaners besides just the Bromothane products.
The exposures badges are an easy way for the employee to determine the exposure to a chemical. While wearing the badge on the collar of their shirt, each employee simply goes about their daily routine. After wearing the badge for eight hours, the badge is sent to an independent lab to determine exposure levels.
Yes, it is safe to heat the MicroCare cleaners, the Dupont Vertrel® products and the Bromothane™ cleaning agents. In fact, they are designed for it!
First, these cleaning products have no flashpoint and are nonflammable. In addition, they are extremely stable. This means that under normal conditions during storage and use the products will not deteriorate in any way.
Lastly, these products are all true azeotropes or near-azeotropic blends which retain their proportions across all the normal temperature ranges, even when distilled. This specific feature makes them ideal for use in heated cleaning systems, and especially in vapor degreasers.
For more details, see the Learning Center.
The simple answer is no, none of the MicroCare precision cleaners are flammable. All of these products are nonflammable azeotropes or nonflammable near-azeotropes. Specifically, none of the the MicroCare precision cleaners exhibit a tag closed cup flash point. The products are rated as nonflammable according to the Tag Closed Cup Method ( ASTM-D-56). Because of these test results, none of the solvents are classified as flammable liquids by either the National Fire Protection Association (NFPA) or the Department of Transportation (DOT). For further details, check the Product Specification and/or the Safety Data Sheet for the specific product.
(SPECIAL NOTE: Vertrel® XSi and the BromoBooster™ concentrate are flammable mixtures. These two products need to be handled with all the normal care and caution used on any flammable material, such as isopropyl alcohol. See the Product Specifications for details.)
Skin and eye contact are the most common risks. Impervious gloves and protective clothing are the best choice if there is any potential for skin contact. Gloves, splash goggles, aprons (when handling open drums), and safety shoes with steel toes are highly recommended.
MicroCare recommends gloves made of butyl rubber or other materials to provide optimal protection; Viton® gloves also work adequately. Chose the powderless option if it is important to control nonvolatile residues in your production process. These are widely available from quality distributors everywhere.
Vapor degreasers filled with the MicroCare cleaners are very safe cleaning systems. However, during maintenance technicians may be exposed to unusually high concentrations of vapors. Users should be aware that solvent vapors are four to eight times heavier than air. These heavy vapors will displace the air in a confined space. In the event of a spill, and before attempting any remediation or control measures, evacuate the area and thoroughly ventilate the work spaces.
If there is any concern that a very high concentration of vapors may exist (such as during a spill) supervisors should follow the safety regulations specified by O.S.H.A. in the U.S. Code of Federal Regulations CFR 29 for safe tank entry procedures. Contact your company’s Health and Safety manager or O.S.H.A. for details on these specifications.
To ventilate a confined area, use fans to force air down to the lowest point in the area. Monitor the composition of the atmosphere in the area. Before it will be safe to enter the area safely without an independent air supply, the oxygen content should be at least 18.5% and the concentration of solvent vapors should be below the AEL for the solvent in use.
Because the MicroCare cleaners are nonflammable and non-corrosive, they are not regulated as hazardous materials by the Department of Transportation. Even though some cleaning agents are mixtures that include other solvents such as alcohol, none of the mixtures are classified as flammable, poisonous or corrosive by the friendly folks at the D.O.T. They all are shipped under the classification of “Non-Regulated/Non-Hazardous.”
(SPECIAL NOTE: The BromoBooster™ stabilizer concentrate and the Vertrel® XSi are flammable and are regarded as a hazardous for transportation purposes. From a practical point of view, this is only critical if you are shipping the material by air. For normal ground transportation, it’s mostly a paperwork issue.)
As for disposal, the same rules would apply unless the user has introduced a RCRA hazardous material during use. Users should test the exhausted product to ensure proper RCRA classification for waste disposal and should check local, state, and federal requirements in determining disposition of spent product. Most spent solvent is incinerated in cement kilns; typically that service costs $150 per drum. Contact your hazmat disposal service for details; normally they will require a chemical analysis of the material to determine the exact chipping classification.
Yes. All of the MicroCare cleaning fluids products and their ingredients have been reviewed under the Significant New Alternatives Program at the U.S. Department of Environmental Protection. The E.P.A. has made it’s final ruling and approved these cleaners for the marketplace. The approval for nPB (the Bromothane™ cleaners) is restricted to the metal finishing industry, electronics manufacturing and precision cleaning, but all other products have approvals that are unrestricted.
No, the MicroCare cleaning fluids are not themselves approved by the U.S. Food and Drug Administration. The F.D.A. approves products that are marketed as medicines and have proven medicinal benefits, or are part of machines, tools or systems used in medical procedures. It is perfectly acceptable to use the MicroCare cleaning fluids on medical products for cleaning and surface preparation because the solvents evaporate completely and leave no residues. The manufacturer needs to document the cleaning process and may need specific approvals from the F.D.A.