METHOD FOR FORMING DOUBLE-LAYERED COATING FILM

• Main Authors: TAKEZAWA SHOICHIRO, SHIRAI NOBUYOSHI
• Format: Patent
• Language: English
• Published: 25.03.1997
• Edition: 6
• 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; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; 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; TRANSPORTING; USE OF MATERIALS THEREFOR; WOODSTAINS

PROBLEM TO BE SOLVED: To obtain a cured coating film with excellent mechanical physical properties, scratch resistance, weatherability etc., by applying a water-based base coat resin compsn. and performing powder coating of a powder coating resin compsn. contg. a specified epoxy group-contg. vinyl polymer and an aliph. dibasic acid as essential components. SOLUTION: When a double-layered coating film is formed on an automotive car body, after a water-based base coat resin compsn. is applied on an article to be coated, a powder coating resin compsn. contg. a vinyl polymer contg. epoxy groups in a molecule obtd. by using a polymerizable monomer of the formula (wherein R1 is hydrogen atom or a methyl group) as an essential monomer component and polymerizing it and an aliph. clibasic acid as essential film forming components is applied thereon and this is baked and dried. As the vinyl polymer with epoxy groups, such a polymer that has a softening point based on a ring and ball softening point method in the range of about 80 - about 150 deg.C and has a number average MW in the range of about 1,000 - about 10,000, is used.