Page 1 SWA Safewash Original SWA is ideally suited for the removal of flux resides and many other cleaning applications that do not contain sensitive metals and substrates. Used for cleaning metals prior to plating operations to provide an extremely clean and slightly roughened surface, allowing excellent bonding of the plated material. It is ready to use and is part of the Electrolube Safewash range water-based, non-flammable, biodegradable solvent blends designed to clean to within military cleanliness standards, (ANSI-J-001B/IPC TM-650). Removes flux residues and other contaminants suitable for micro-etching processes prior to plating Good for general degreasing applications ideal for applications that do not contain sensitive metals Ready to use for ultrasonic applications no dilution required Non-flammable product, 100% ozone friendly suitable for use in standard cleaning equipment Approvals RoHS-2 Compliant (2011/65/EU): Yes Typical Properties Appearance Green Liquid Boiling Point (C) 98 Flash Point (C) None Freezing Point (C) -5 Density 20C (g/ml) 1.002 Viscosity 20C (mPa s) 5-10 pH 11.7 Conductivity 18C (mS) 1.15 Description Packaging Order Code Shelf Life Safewash Original 5 Litre SWA05L 48 Months 25 Litre SWA25L 48 Months 200 Litre SWA200L 48 Months Page 2 Directions for Use SWA has been specifically developed for use in 3 or 4 stage batch cleaning systems using ultrasonic or spray- under-immersion. It is supplied at a concentration suitable for immediate use and further dilution is not recommended. In typical usage times and temperatures, SWA has good compatibility with most materials used in the electronics industry, and with materials used in cleaning equipment. For sensitive plastics such as polycarbonate and ABS, testing is recommended to confirm compatibility. Stage 1 - Cleaning: Typically 3-5 minutes with agitation. Safewash is designed to be used at ambient temperature, though if required this can be increased up to 45C. The temperature of the rinsing solution can be ambient, but higher temperatures in Stage 2 Tap water rinse: addition to agitation, will accelerate and improve rinsing. Stage 3 Deionised water rinse: This may either consist of a re-circulating rinse or a spray system that is activated when the PCBs leave the tap water rinse. If military standard cleanliness is not required, this deionised rinse may not be necessary, though the PCBs may show some white streaking due to tap water impurities. For ferrous metal cleaning operations it is possible to add a rust inhibitor (Code: SRIA) at 0.5% into this stage. This will prevent flash rusting of ferrous metals when they are dried at high temperatures. Stage 4 Drying: The length of time required to dry the PCB depends on the circuit design and the efficiency of the drying unit itself. This is enhanced by equipment that uses high air flow as opposed to heat only systems. In general, this stage takes approximately 5 minutes at 90C. Air-knives can be used as an optional extra to reduce temperature or total energy required. Evaluation of Flux Concentration - Conductivity Method The electrical conductivity of a Safewash solution will increase with flux concentration (and other ionic contami- nants). Once it has been determined how much flux the Safewash can take up, while still achieving the cleanliness level required, the method below can be used to determine a method for monitoring the solution. Whilst conductivity and other methods may be used to assess the contamination level, the critical test for replacement is when the process is not cleaning the boards to the desired standards. A range of flux / Safewash solutions should be made up at 0.5, 2.5, 5, 7.5, 10 and 15%. For solder pastes, thoroughly mix 100g of the paste with 100g of Safewash. Heat the mixtures to 50C for 4 hours. Cool to room temperature and measure the conductivity of the liquid at a suitable fixed temperature. If the flux content of the paste is 10%, this gives a figure for the 10% flux in Safewash. Serial dilution of this master solution will allow a graph of conductivity/ concentration to be prepared.