Foam inhibitors for aqueous synthetic resin compositions

摘要

The formation of troublesome microfoams in aqueous lacquer and synthetic resin dispersions, particularly in gloss lacquers, is prevented by the addition of from about 0.01 to about 1.5% by weight of a silicone-free foam inhibitor mixture. This mixture consists of (a) from about 70 to about 98% by weight of a mineral oil liquid at room temperature or a mixture of such mineral oil with a C16-C30 branched alcohol of the following formula R1-CH2-CH2-CHR2-CH2-CH2-CH2OH(I) in which R1 and R2 are C4-C16 alkyl radicals, (b) from about 0.2 to about 5% by weight of a microcrystalline wax, (c) from about 0.5 to about 20% by weight of hard paraffin, (d) from 0.05 to 5% by weight of hydrophobized finely divided silica, and (e) from 0 to about 10% by weight of a soft paraffin (M.p. 32 DEG -42 DEG C.). Component (a) preferably consists of a mixture of mineral oil and branched alcohol (I) in a ratio of from 50:1 to 1:1.