Improvements in or relating to salts of hydrazinium hydrazones particularly useful as solder fluxes

摘要

The invention relates to bis-hydrazone salts of dibasic acids having the general formula FORM:0719889/IV (b)/1 wherein n is an integer from 1 to 8, R1 and R3 are alkyl radicals and R2 and R4 are hydrogen or alkyl radicals, preferably methyl radicals, the total number of carbon atoms in R1 plus R2 and R3 plus R4 respectively, being not more than 14. They may be prepared by reacting an appropriate aldehyde or ketone with a dihydrazinium salt of the dibasic acid or by first forming the hydrazone of the carbonyl compound and converting this into the salt by means of the stoichiometric amount of dibasic acid. The compounds may be used as fluxes (see Group II). Examples describe the production of bis (acetone hydrazone) adipate. Other carbonyl starting materials and dibasic acids mentioned are propionaldehyde, butyraldehyde, 2-ethyl butyraldehyde, n-hexaldehyde, 2-ethyl hexaldehyde, methyl ethyl ketone, diethyl ketone, isopropyl ketone, isobutyl ketone, ethyl butyl ketone, di-isobutyl ketone, trimethyl acetone, nonanone and malonic, succinic, glutaric, pimelic, suberic, azelaic and sebacic acids.ALSO:Compounds having the general formula FORM:0719889/II/1 wherein n is an integer from 1 to 8, R1 and R3 are alkyl radicals and R2 and R4 are hydrogen and alkyl radicals, the total number of carbon atoms in R1 plus R2 and in R3 plus R4 respectively, being not more than 14, may be used alone or with suitable additives as solder fluxes especially for use with soft solders. Fluxes p described comprise 5 to 10 parts bis (acetone hydrazone) adipate, 45-40 parts rosin and 50 parts iso propanol, The preparation of the above adipate is described and many starting materials for the reduction of similar compounds of the specified formula are given (see Group IV(b)).