Patent ID: 7402627

Claim:
A colorant composition suitable as a precursor to an aqueous latex paint, which colorant composition consists essentially of at least one pigment, water, and a copolymer surfactant having a number average molecular weight of from about 400 Daltons to about 200,000 Daltons comprising the following monomers (a) from about 10% to about 80% by weight of at least one C 3 -C 12 α,β-ethylenically unsaturated carboxylic acid or anhydride, (b) from about 10% to about 80% by weight of at least one C 2 -C 12 α,β-ethylenically unsaturated vinyl monomer, and (c) from about 0.01% to about 20% by weight of at least one surfactant monomer, wherein each said surfactant monomer is either an acrylic or methacrylic ester moiety joined with a hydrophobic moiety which is styrylphenyl by a bridging group consisting essentially of a poly(ethyleneoxy) moiety, which colorant composition is not itself an aqueous latex paint, and which colorant composition is capable of causing the Stormer low-shear viscosity of an aqueous latex paint formed of a mixture comprising said composition and a tint-base to be within about ±10% of the Stormer low-shear viscosity of said tint-base.