Abstract: Provided is a water-based coating composition capable of forming a multilayer coating film having an excellent finished appearance and having excellent storage stability. A water-based coating composition to be used as a water-based first colored coating (X) in a 3-coat-1-bake multilayer coating formation method which sequentially applies a water-based first colored coating (X), a water-based second colored coating (Y), and a clear coating (Z) and heats and cures the obtained three-layer multilayer coating film simultaneously, wherein the water-based coating composition contains at least one resin selected from acrylic resins (A) and polyester resins (B), a curing agent (C), and urethane resin particles (D) obtained from structural components including a polyisocyanate component (d1) containing at least one diisocyanate (d1-1) selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate and a polyol component (d2).

Abstract: The present invention provides acrylic resin-modified silica particles which, when used in a coating composition, enable the coating composition to form a coating film that exhibits excellent scratch resistance and excellent adhesion during recoating (recoat adhesion). The acrylic resin-modified silica particles contain silica particles (A) and an acrylic resin (B) bonded to the silica particles (A), the acrylic resin (B) having at least one chain selected from the group consisting of a polyoxyalkylene chain and a polyester chain and having a polysiloxane structure.

Abstract: Provided is a water-based coating composition capable of forming a multilayer coating film having an excellent finished appearance and having excellent storage stability. A water-based coating composition to be used as a water-based first colored coating (X) in a 3-coat-1-bake multilayer coating formation method which sequentially applies a water-based first colored coating (X), a water-based second colored coating (Y), and a clear coating (Z) and heats and cures the obtained three-layer multilayer coating film simultaneously, wherein the water-based coating composition contains at least one resin selected from acrylic resins (A) and polyester resins (B), a curing agent (C), and urethane resin particles (D) obtained from structural components including a polyisocyanate component (d1) containing at least one diisocyanate (d1-1) selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate and a polyol component (d2).