COLORED METALLIC PIGMENT FOR POWDER COATING AND POWDER COATING COMPOSITION CONTAINING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve the appearance of a coating film by attaching a coloring pigment to the surface of a base metallic pigment, coating the surface of the resultant colored metallic pigment with a polymer formed in-situ, and reducing the residual solvent content to a specified value or lower. ;SOLUTION: A coloring pigment having a primary particle size of 0.01-1μm and in an amt. of 0.01-0.5g per m² of the surface of a base metallic pigment comprising metal flakes (pref. aluminum flakes having a thickness of 0.1-5μm and an average flake size of 5-100μm), an arom. monocarboxylic acid in an amt. of 0.2-100wt.% of the coloring pigment, and if necessary an Al or Ti chelate compd. in an amt. of 0.1-50wt.% of the colorinrg pigment are dispersed in a nonpolar solvent to give a surface-treated coloring pigment dispersion. After the dispersion is mixed with the above-mentioned base metallic pigment to form a colored metallic pigment, a polymerizable monomer and a polymn. intiator are added to the mixture, which is then heated under stirring to polymerize the monomer, thus causing 100 pts.wt. colored metallic pigment to be coated with 0.5-100 pts.wt. polymer. The resultant product is subjected to solid-liq. separation to give a paste, from which the solvent is removed by stirring under heating and reduced pressure.;COPYRIGHT: (C)1997,JPO