PURPOSE: To provide titled solvent compsn. which is particularly suitable for the washing of circuit boards and by which the solubility of a flux is increased, by a method wherein 1,1-dichloroethane is added to a mixed solvent consisting of trichlorotrifluoroethane, ethanol and nitromethane.
CONSTITUTION: There is provided an azeotropic mixed solvent compsn. consisting of (i) 89.6wt% of 1,1,2-trichloro-1,2,2-trifluoroethane, (ii) 3.7wt% of ethanol, (iii) 6.5wt% of 1,1-dichloroethane and (iv) 0.2wt% of nitromethane. Each component may be added in any order. The compsn. can be obtd. by mixing the above components together in the mixing proportion stated above. Alternatively, the compsn. can be obtd. by mixing the above components in an arbitrary ratio and distilling the resulting mixt.
EFFECT: The compsn. excels in noncombustibility and corrosion inhibiting properties against metals.
USE: Useful for the removal of dust and a fingerprint and for the degreasing of precision apparatuses, glasses, plastics and ceramic parts.
MAEDA TOMOAKI
OOMURE YUKIO
NISHIWAKI MITSUHIRO
