Patent ID: 6919400

Claim:
A fluid opacifying pigment mixture having a titanium dioxide pigment volume concentration of about 40 to about 100%, a titanium dioxide volume solids content of at least about 15%, and a Stormer viscosity of about 50 to about 250 KU, which mixture comprises: (a) about 600 to about 1500 lbs/100 gallons of at least one universal-grade titanium dioxide; (b) about 0.2 to about 20 lbs/100 gallons of at least one hydrophobically-modified ethylene oxide-urethane polymer (HEUR) thickener selected from the group consisting of: (i) a HEUR having a C 4 -C 12 hydrophobe and a molecular weight of about 10,000 to about 200,000, (ii) a HEUR having a C 6 -C 30 hydrophobe and a molecular weight of about 10,000 to about 200,000, and (iii) combinations thereof, (c) about 1.5 to about 16 lbs/100 gallons of at least one dispersant selected from the group consisting of a maleic acid/diisobutylene copolymer, a butyl methacrylate/methacrylic acid copolymer, and an acrylic acid/hydroxypropyl acrylate copolymer; and (d) water.