Aqueous two-package type clear coating composition and process for the formation of multilayer finish coating film

• Main Authors: NOGUCHI TAKASHI, WADA SEIJI, ONOYAMA HIROYUKI, SUGAI HIDEO, CHIGA KOKI, ADACHI TAKATO, BABA YUTA
• Format: Patent
• Language: English
• Published: 22.10.2013
• Subjects: ADHESIVES; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; PERFORMING OPERATIONS; POLISHES; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; SPRAYING OR ATOMISING IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS; USE OF MATERIALS THEREFOR; WOODSTAINS

The present invention provides an aqueous two-package type clear coating composition comprising: (A) an aqueous dispersion of a hydroxyl group- and acid group-containing acrylic resin having a hydroxyl value of 30 to 200 mg KOH/g, an acid value of 5 to 50 mg KOH/g, a weight average molecular weight of 3,000 to 30,000, and a glass transition temperature of -30 to +40° C. obtained by radical polymerization of 10 to 50 mass % of a secondary hydroxyl group-containing monomer (a) and 50 to 90 mass % of at least one other unsaturated monomer (b); and (B) a polyisocyanate curing agent obtained by mixing (c) a polyisocyanate compound and (d) a compound containing an anionic functional group, a polyoxyethylene group, and a hydrocarbon group, and a process for forming a multilayer topcoat film using the same.