Pigment dispersions containing hydroxylated AB-block polymer dispersant

A pigment dispersion useful for forming coating composition comprising dispersed pigment, a carrier liquid and an AB-block polymer dispersant (binder);

• the AB block polymer has a number average molecular weight of about 5,000-20,000 and consists of 20-80% by weight of a polymeric A segment and correspondingly 80-20% by weight of a polymeric B segment;
• wherein
• the polymeric A segment of the block polymer consists essentially of polymerized glycidyl (meth)acrylate monomers reacted with an acid selected from the group consisting of aromatic carboxylic acids and aliphatic carboxylic acids;
• and
• the polymeric B segment containing reactive hydroxyl groups consists essentially of polymerized alkyl (meth)acrylate monomers having 1-12 carbon atoms in the alkyl group and hydroxy alkyl (meth)acrylate monomers having about 1-4 carbon atoms in the alkyl group and the polymeric B segment having a number average molecular weight of at least 1500;
• and
• wherein the AB block polymer is prepared by group transfer polymerization;
• and
• wherein the weight ratio of pigment to binder in the dispersion is about 1/100-200/100.