Patent ID: 6177065
Filing Date: 2001-01-23
Classification: A61K,A61Q

Abstract:
A method for producing an aqueous nail enamel composition which comprises kneading under heating an aqueous mixture comprising, as essential components, water and a pigment of 3 .mu.m or less in average particle size at a concentration of the pigment of 60% or less and previously subjected to contact treatment with a substance having ion exchangeability, with a polyester polymer having a chemical structure containing a phenyl group and having a weight-average molecular weight of 2000-20000 and a softening point of 120.degree. C. or lower in the state of the polymer being molten and simultaneously removing the volatile matter contained under reduced pressure; dissolving the resulting mixture (A) comprising the polyester polymer and the pigment dispersed in the polyester polymer, said pigment having finally the inherent average particle size, in an organic solvent at a concentration of the mixture (A) of 50% by weight or less; mixing the resulting solution with an organic solvent solution (B) containing 80% or less of a resin containing 1-5 meq/g of a functional group capable of being dissociated to a cation or an anion; neutralizing the resulting mixture and allowing the mixture to contact with a substance having ion exchangeability to remove ionic impurities before and/or after carrying out phase inversion by dilution with addition of water; distilling off the organic solvent; and again allowing the residue to contact with a substance having ion exchangeability to obtain an aqueous nail enamel composition comprising a color polymer composition dissolved in only water as an essential component and containing less ionic impurities and substantially no organic solvent and film-forming aid.