| abstract |
A hydroxy-functional polymeric dispersant which is substantially free of acid groups, amine groups, and ethylenic unsaturation, the dispersant being especially adapted for dispersing pigments therein and being compatible with a variety of film-forming polymers, said dispersant being the free radical addition polymerization reaction product of a mixture of monomers consisting essentially of: n (a) 15-30% by weight styrene; and n (b) 15-30% by weight of at least one alkyl methacrylate monomer having 1 to 16 carbon atoms in the alkyl group; and n (c) 20-60% by weight of at least one alkyl acrylate monomer having 1 to 16 carbon atoms in the alkyl group; and n (d) 7-25% by weight of at least one hydroxy-functional ethylenically unsaturated monomer copolymerizable with monomers (a) (b) and (c); n wherein said polymeric dispersant has a weight average molecular weight of 18,000 to 24,000, a number average molecular weight of 4,500 to 7,400, and a polydispersity of 2.9 to 4.2. |