Pigment dispersion composition

摘要

The present invention discloses a pigment dispersion composition for depositing a multiplicity of pores existing in anodic oxide films formed on a surface of an aluminum or aluminum alloy material by way of electrophoresis for coloration, the pores being preliminarily enlarged to have a diameter of 50 nm to 250 nm. The pigment dispersion composition comprises water, a pigment dispersant and a pigment. The pigment dispersed in the pigment dispersion composition has a median particle size of not greater than 250 nm in a particle-size distribution thereof with not greater than 30% of the pigment particles being impassable through a sieve having a mesh size of 300 nm. The pigment dispersion composition is useful for coloration of the anodic oxide films, and has excellent repeated-coloration characteristics.