03.14.08
Patent No. U.S. 7,220,797 B2
Nippon A&L Inc. has obtained a patent for a method for producing a copolymer latex for chip-resistant aqueous paint. The method is comprised of emulsion-polymerizing 20-80 parts by weight of a conjugated diene as a monomer, 0.5-15 parts by weight of an ethylenically unsaturated carboxylic acid as a monomer, 5-40 parts by weight of an aromatic vinyl compound as a monomer, 5-40 parts by weight of an unsaturated alkyl carboxylate as a monomer and optionally not more than 69.5 parts by weight of other compound having vinyl group copolymerizable therewith as a monomer based on 100 parts by weight in the total of the monomers, wherein 100% weight of the amount of conjugated diene, 100% weight of the amount of ethylenically unsaturated carboxylic acid, 95-50% weight of the amount of aromatic vinyl compound and 95-50% weight of the amount of the unsaturated alkyl carboxylate are added in the former stage of the emulsion-polymerization, and 5-50% weight of the amount of the aromatic vinyl compound and 5-50% weight of the amount of the unsaturated alkyl carboxylate are added at the later stage of emulsion-polymerization.
Nippon A&L Inc. has obtained a patent for a method for producing a copolymer latex for chip-resistant aqueous paint. The method is comprised of emulsion-polymerizing 20-80 parts by weight of a conjugated diene as a monomer, 0.5-15 parts by weight of an ethylenically unsaturated carboxylic acid as a monomer, 5-40 parts by weight of an aromatic vinyl compound as a monomer, 5-40 parts by weight of an unsaturated alkyl carboxylate as a monomer and optionally not more than 69.5 parts by weight of other compound having vinyl group copolymerizable therewith as a monomer based on 100 parts by weight in the total of the monomers, wherein 100% weight of the amount of conjugated diene, 100% weight of the amount of ethylenically unsaturated carboxylic acid, 95-50% weight of the amount of aromatic vinyl compound and 95-50% weight of the amount of the unsaturated alkyl carboxylate are added in the former stage of the emulsion-polymerization, and 5-50% weight of the amount of the aromatic vinyl compound and 5-50% weight of the amount of the unsaturated alkyl carboxylate are added at the later stage of emulsion-polymerization.