Corrosion-inhibiting compositions and functional fluids containing same

Abstract

The invention provides a composition comprising: (A) at least one dicarboxylic acid or anhydride or at least one ammonium or metal salt of the dicarboxylic acid or anhydride; and (B) at least one compound represented by the formula ##STR1## wherein R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently hydrogen, alkyl, hydroxyalkyl, polyhydroxyalkyl, polyalkoxyalkyl or hydroxypolyalkoxyalkyl; and R.sub.1 is a hydrocarbyl group. In another embodiment, the compositions include (C) at least one acid, or ammonium or metal salt of the acid represented by the formula: ##STR2## wherein R.sub.6, R.sub.7, R.sub.8 and R.sub.9 are each independently hydrogen or hydrocarbyl groups; and n is a number from 1 to about 10; (D) at least one ester-salt derived from at least alkyl or alkenyl succinic acid or anhydride of about 8 to about 28 carbon atoms and at least one alkanol amine; or mixtures of (C) and (D). The invention further provides for concentrates and functional fluids containing the above corrosion-inhibitors.

Dependencies are inferred from the claim text.