Patent ID: 8445579

Claim:
A method of preparing a paint, the method comprising: dry-grinding a calcium carbonate in the presence of a grinding aid agent comprising a copolymer comprising: a) an anionic monomer comprising acrylic acid methacrylic acid, or a mixture thereof; b) a non-ionic monomer of formula (I) wherein m, n, p, and q are integers such that m, n, and p≦150, q≧1, and 5≦(m+n+p) q≦150, R 1 and R 2 are independently hydrogen, methyl, or ethyl, R is a radical comprising an unsaturated polymerizable function selected from the group consisting of a vinylic, an acrylic ester, a methacrylic ester, a maleic ester, an acrylurethane, a methacrylurethane, an α-α′ dimethyl-isopropenyl-benzylurethane, an allylurethane, an optionally substituted allylic ether, an optionally substituted vinylic ether, an ethylenically unsaturated amide, an ethylenically unsaturated imide, an acrylamide, and a methacrylamide; R′ is hydrogen or a hydrocarbon radical comprising 1 to 40 carbon atoms; and c) optionally, a further monomer selected from the group consisting of (meth)acrylic anhydride, a (meth)acrylamide, an acrylate comprising 1 to 20 carbon atoms in its ester radical, a methacrylate with 1 to 20 carbon atoms in its ester radical, a hydroxylated methacrylate, an aromatic vinylic monomer, an acrylate phosphate of ethylene glycol, an acrylate phosphate of oxyethylene glycol, an acrylate phosphate of oxypropylene glycol, an acrylate phosphate of oxyethylene and oxypropylene glycol, a methacrylate phosphate of ethylene glycol, a methacrylate phosphate of oxyethylene glycol, a methacrylate phosphate of oxypropylene glycol, and a methacrylate phosphate of oxyethylene and oxypropylene glycol.