| abstract |
Corrosion-inhibited compositions are described comprising a functional fluid in contact with a ferrous metal and, as corrosion inhibitor, a compound having the formula: <IMAGE> wherein X is H, an alkali- or alkaline earth metal, NH4, the residue of a protonated amine, or the group -OX is the residue of an alkanol having from 1 to 20 carbon atoms or of di-, tri- or tetra-ol having from 2 to 12 carbon atoms; R1, R2 and R4 are the same or different and each is H or -CH2CH2COOX wherein X has its previous meaning; R3 and R5 are the same or different and each is H, -CH2CH2COOX wherein X has its previous meaning, or R3 or R5 is a straight- or branched chain alkyl group having from 3 to 16 carbon atoms; or R3 and R5, together with the carbon atom to which they are each attached, may form a cycloalkanone ring containing from 5 to 15 carbon atoms. |