Abstract: There is provided a method for producing a carboxyl group-containing polymer composition that is excellent in all of the following: dispersibility in water or the like immediately after the preparation, storage stability, and the transparency of a neutral viscous solution thereof. A method for producing a carboxyl group-containing polymer composition, the carboxyl group-containing polymer composition comprising a carboxyl group-containing polymer (A) that is a copolymer of monomers comprising an ?,?-unsaturated carboxylic acid (a-1) and a compound (a-2) having at least two ethylenically unsaturated groups per molecule; and a nonionic surfactant (B), the method comprising the step of copolymerizing the monomers, wherein in the step, the nonionic surfactant (B) is added into the system when the polymerization degree of the ?,?-unsaturated carboxylic acid (a-1) has reached 70 to 100%.

Abstract: There is provided a gel composition that can be suitably used as a thickener for cosmetic preparations and the like. A gel composition comprising a neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of monomers comprising 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of a (meth)acrylic acid alkyl ester (b) in which the alkyl group has 18 to 24 carbon atoms, and 0.1 part by mass or less of a compound (c) having two or more ethylenically unsaturated groups; and at least one of an anionic emulsifier and a nonionic emulsifier.

Abstract: There is provided a gel composition that can be suitably used as a thickener for cosmetic preparations and the like. A gel composition comprising a neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of monomers comprising 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of a (meth)acrylic acid alkyl ester (b) in which the alkyl group has 18 to 24 carbon atoms, and 0.1 part by mass or less of a compound (c) having two or more ethylenically unsaturated groups; and at least one of an anionic emulsifier and a nonionic emulsifier.

Abstract: There is provided a gel composition that comprises a betaine-based emulsifier and can be suitably used as a thickener for cosmetic preparations and the like. A gel composition comprising a neutralized product of an alkyl-modified carboxyl group-containing polymer, which is a copolymer of monomers comprising 100 parts by mass of (meth)acrylic acid (a), 2.5 to 5 parts by mass of a (meth)acrylic acid alkyl ester (b) in which the alkyl group has 18 to 24 carbon atoms, and 0.1 part by mass or less of a compound (c) having two or more ethylenically unsaturated groups; and a betaine-based emulsifier.

Abstract: There is provided a method for producing a carboxyl group-containing polymer composition that is excellent in all of the following: dispersibility in water or the like immediately after the preparation, storage stability, and the transparency of a neutral viscous solution thereof. A method for producing a carboxyl group-containing polymer composition, the carboxyl group-containing polymer composition comprising a carboxyl group-containing polymer (A) that is a copolymer of monomers comprising an ?,?-unsaturated carboxylic acid (a-1) and a compound (a-2) having at least two ethylenically unsaturated groups per molecule; and a nonionic surfactant (B), the method comprising the step of copolymerizing the monomers, wherein in the step, the nonionic surfactant (B) is added into the system when the polymerization degree of the ?,?-unsaturated carboxylic acid (a-1) has reached 70 to 100%.