We have compiled a list of frequent questions below, which may help you. However please don’t hesitate to contact us if you have any questions which are not answered sufficiently well.
SF79 is a brand new Patented non-flammable, fast drying cleaning solvent from Chemours™ designed to clean a wide range a soils form mechanical components, Electronics, Optics, Military hardware etc both in existing solvent cleaning systems and for hand cleaning applications. SF79 has been designed to be safe for the operators and for the Environment and will successfully replace many of the High cost HFE materials as well as nPB, HFC-365 blends and other hazardous Chlorinated solvents such as Trik, Methylene Chloride and Perk. SF79 can also be used as a safe, viable alternative to fast evaporating flammable materials such as IPA, Acetone, Thinners, MEK, typically used in hand cleaning applications.
SF79 is a blend of two key chemicals and both have been registered under REACH. SF79 has no chemicals registered as SVHC.
SF79 is typically used as a replacement for either Hazardous or high cost cleaning solvents for the removal of oils, flux, liquors, paint, machining or sanding particulate. SF79 has a very high wetting index (low surface tenSF79, viscosity and density) and can remove particulate down to submicron levels and will leave no residues.
SF79 has a high solvency (KB value of100) comparable to Methylene chloride, Trik, Perk, nPB, it solvency is twice that of similar HFE materials providing significant improvements in cleaning and in service life.
SF79 has an 8 hr WEL of 200 ppm (EH40). Typical exposure levels around standard equipment would be around 5 – 10 ppm providing a significant margin of safety. The figure of 200 ppm is comparable to IPA (Isopropyl Alcohol) widely used as a hand cleaning chemical.
SF79 is the lowest cost HFO based Fluorinated solvent on the market today however material costs are only one element to consider and the overall cost of the process should be considered when looking at the cost of a solvent cleaning process as each application is different. Due to the unique characteristics of SF79 emissive losses in typical equipment will be around half that of Chlorinated solvents and around a 25% reduction over older generation high value HFC or HFE materials.
SF79 is very effective on a wide range of soils however cleaning trials should be carried out to ensure that the required results are achievable. Fraser Technologies can run trials to ascertain the effectiveness and compatibility of SF79 ™ with your components.
SF79 has a GWP of less than 15 meaning it is the lowest GWP of any fluorinated solvent on the market today by a significant margin.
Global-warming potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere. It compares the amount of heat trapped by a certain mass of the gas in question to the amount of heat trapped by a similar mass of carbon dioxide. A GWP is calculated over a specific time interval, commonly 20, 100 or 500 years. GWP is expressed as a factor of carbon dioxide (whose GWP is standardized to 1). For example, the 20 year GWP of methane is 72, which means that if the same mass of methane and carbon dioxide were introduced into the atmosphere, that methane will trap 72 times more heat than the carbon dioxide over the next 20 years.
SF79 contains no materials regulated under the F-Gas regulations.
SF79 is an R20 based solvent and as such the SED does apply however the SED threshold limit for SF79 is 2 metric tons.
nPb is an R60 chemistry which is Mutagenic and, therefore, strictly regulated in its use. With the US now recommending 0.1 ppm exposure limit nPb is becoming very difficult to use safely. SF79 has a similar solvency to nPB and in most cases will work equally as well as nPB however it does have a slightly lower boiling point so applications that rely on the high temperature of nPB to assist the cleaning may struggle. Fraser Technologies can run cleaning trials with SF79 to ascertain if the process is suitable for your application.
Trik is an R45 chemistry which is Carcinogenic and, therefore, strictly regulated in use with specific permits required. SF79 has a similar solvency to Trik and in most cases will work equally as well as Trik however it does have a lower boiling point so applications that rely on the high temperature of Trik to assist the cleaning may struggle. Fraser Technologies can run cleaning trials with SF79 to ascertain if the process is suitable for your application.
SF79 has the highest solvency power of any Fluorinated solvent, in general terms this will improve cleaning, allow a higher level of contamination (reducing the frequency of tank clean outs) and has the lowest GWP of any Fluorinated solvent on the market today. SF79 also has a low “in use” cost with significant savings to be had over traditional Fluorinated solvents.
Despite containing a flammable chemistry SF79 is not a flammable Solvent. This is down to the unique patented “Azeotropic” mix of a special inerting agent used to eliminate the flammable element of the solvent. As this is a true Azeotrope the % mix of the chemistry remains unchanged providing a stable, non-Flammable solvent.
An azeotrope is a mixture of two or more liquids in such a way that its components cannot be altered by simple distillation. This happens because, when an azeotrope is boiled, the vapor it produces has proportionate constituents as the original mixture.
Because their composition is unchanged by distillation, azeotropes are also called (especially in older texts) constant boiling mixtures. The word azeotrope is derived from the Greek words ζέειν (boil) and τρόπος (state) combined with the prefix α- (no) to give the overall meaning, “no change on boiling”.
SF79 is an azeotrope having no Flash Point (FP) either in open cup or in a closed cup. Its fluorinated components give this unique no Flash Point property to solvents containing high levels of Trans.
However, there are statements in the material safety data sheet (MSDS) and Technical data sheet (TDS) that warrant further explanation:
- In section 9 of the MSDS it is detailed that although there is no FP there is an upper explosion ™ limit and lower explosion ™ limit (UEL and LEL) of 7 to 14 % (70,000 – 140,000 ppm). When using any solvent in cleaning equipment there are 2 possibilities:
- The vapour is totally saturated (1,000,000 ppm), in which case there is no risk.
- The vapour is condensed and the concentration is well below 0.002 % wt (200
Both of these potential scenarios are well away from the 7-14% LEL and UEL’s. Many solvents have no flash point but have LEL – UEL’s.
See table below for similar products and limits
|SOLVENT||Lower Explosion ™ Limit||Upper Explosion ™ Limit|
|HCFC – 141b||7.6%||16.7%|
|Novec HFE 72DA||5.9%||14.5%|
In section 2 of the MSDS there is a sentence ” In use, may form flammable/explosive vapour-air mixture “. Although this is not true for SF79, we have to insert this statement to comply with DIRECTIVE 1999/45/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 31 May 1999 concerning the approximation of the laws, regulations and administrative provisions of the Member States relating to the classification, packaging and labelling of dangerous preparations, on page 43 of this directive it is stated that:
10. Liquid preparations containing halogenated hydrocarbons
For liquid preparations which show no flashpoint or a flashpoint higher than 55°C and which contain a halogenated hydrocarbon which is more than 5% flammable or highly flammable, the packaging must bear the following inscription as appropriate:
Can become highly flammable in use
Can become flammable in use.
As stated above, SF79 is safe in use and the labelling is based on legislative compliance.
SF79 can be used in almost any solvent cleaning system however some of the older systems may not be suitable due to their overall condition or the fact that the cooling system is not sufficient to contain the solvent properly meaning the process would not be economic to run. An FCT product specialist will be able to advise you on the suitability of your existing equipment.
Yes, SF79 is stable and non-flammable in use. The only recommendation would be to follow the recommendations in the MSDS and insure adequate ventilation. You should always do a risk assessment of any new process and SF79 is no exception to this.
Detailed testing of SF79 has shown that this product is safe for use with these materials. Further material compatibility is available on request.
SF79 is currently being used by a number of major Aerospace companies and new approvals are being granted on a regular basis. An FCT representative will be able to advise you of the latest status.