To provide a water-based primer composition capable of being used as a one-package type which can give a coating film excellent in water resistance, polishability, and adhesion to a substrate.
The water-based primer composition comprises (A) an emulsion-polymerized polymer comprising (a) styrene, (b) an acid group-containing polymerizable unsaturated monomer, (c) a hydroxy group-containing polymerizable unsaturated monomer, and (d) other polymerizable unsaturated monomers as comonomers, wherein the amount of styrene used is 30 wt.% or higher based on the entire monomer, (B) a water-based urethane resin, (C) an acrylic resin comprising (e) a bridged alicyclic hydrocarbon group-containing polymerizable unsaturated monomer, (b) an acid group-containing polymerizable unsaturated monomer, (c) a hydroxy group-containing polymerizable unsaturated monomer, and (f) other polymerizable unsaturated monomers as comonomers, and (D) a pigment, wherein the pigment (D) is present in an amount of 100 to 350 pts.wt. per 100 pts.wt. total resin solids content in the composition, and the pigment (D) comprises an extender in an amount of 50 to 200 pts.wt. per 100 pts.wt. total resin solids content in the composition.
NISHIZAWA YASUAKI
SAKAI HIROYUKI
