Patent ID: 7601790
Filing Date: 2009-10-13
Classification: C08F,C08L,C09D

Abstract:
1. An amphiphilic block copolymer having an ionic functional group, wherein a ratio (N10/N5) of a rotational viscosity (N10) of a 10% by mass solution of the copolymer in purified water to a rotational viscosity (N5) of a 5% by mass solution of the copolymer in purified water is 2.5 or lower, wherein the copolymer has a structure in which a hydrophobic block segment, a nonionic hydrophilic segment, and an ionic hydrophilic segment are arranged in that order, and wherein a degree of polymerization ratio between the hydrophobic block segment, nonionic hydrophilic segment, and ionic hydrophilic segment arranged in that order is such that a proportion of a degree of polymerization of the nonionic hydrophilic segment is 8 or lower and a proportion of a degree of polymerization of the ionic hydrophilic segment is 5 or lower when a proportion of a degree of polymerization of the hydrophobic block segment is regarded as 10.