Patent ID: 8298402

Claim:
An alkylphenol-aldehyde resin containing oligo- or polymers having a repeat structural unit of the formula wherein R 1 is a branched alkyl or alkenyl radical having from 10 to 40 carbon atoms and at least one carboxyl, carboxylate and/or ester group, R 2 is hydrogen or R 1 , wherein R 1 and R 2 are bonded to the aromatic ring system via a secondary carbon atom, R 3 is hydrogen or an alkoxy group of the formula -(A-O) m —H, A is a C 2 - to C 4 alkylene group, m is from 1 to 100, R 4 is hydrogen, a C 1 - to C 11 -alkyl radical or a carboxyl group. R 5 is C 1 -C 200 -alkyl or -alkenyl, or O—R 6 . R 6 is C 1 -C 200 -alkyl or -alkenyl, n is from 1 to 100 and k is 1 or 2.