Patent ID: 7815696

Claim:
A process for improving oxidation stability of at least one partial ester composed of a di- or polyhydric alcohol and a fatty acid mixture of unsaturated and optionally also saturated fatty acids whose carbon chain lengths are between 8 and 30 carbon atoms, wherein at least 60% of said fatty acids have fatty acid radicals containing at least one double bond, said process comprising adding to the at least one partial ester, at least one alkylphenol-aldehyde resin, obtained by the condensation of (i) at least one alkylphenol having at least one C 6 -C 24 -alkyl or C 6 -C 24 -alkenyl radical and (ii) at least one aldehyde or ketone, to a degree of condensation of between 2 and 50 alkylphenol units.