Patent ID: 7432329

Claim:
A dispersing agent for pigments or extenders comprising an acrylic ester-acrylamide polymer having a weight average molecular weight of 1,000 to 50,000 comprising an aminolysis product of an acrylic acid alkyl ester polymer with at least one amine of a formula NH 2 —R 1 -Z, wherein R 1 is a divalent alkylene radical comprising 2-4 carbon atoms and Z is a 5- or 6-membered N-containing heterocycle of up to 2 nitrogen atoms and optionally an oxygen, wherein from 1% to 50% of the ester groups of the acrylic acid alkyl ester units of the polymer are converted to CONH—R 1 -Z groups, and wherein, the acrylic acid alkyl ester polymer is a polymer of acrylic acid alkyl ester monomer alone, or with one or more additional monomers selected from the group consisting of itaconic acid ester, maleic acid ester, methacrylic acid ester, (meth)acrylic acid, styrene, alkyl vinyl ether, vinyl acetate, and at least part of the ester groups of the acrylic ester-acrylamide polymer are transesterified with at least one long chain alcohol selected from the group consisting of oleyl alcohol, stearyl alcohol, benzyl alcohol, methoxy polyethylene glycol, butyl triglycol and allyl polyether.