METHOD FOR PRODUCING EPOXY VISCOUS AGENT FOR CATIONIC ELECTRODEPOSITION COATING MATERIAL

• Main Authors: MIYAMAE, Nobuhiro, AKAGI, Saki, SHIMODAIRA, Yosuke
• Format: Patent
• Language: English; French; German
• Published: 19.04.2023
• Subjects: ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF MATERIALS THEREFOR; WOODSTAINS

The objective of the present invention is to improve the edge corrosion resistance of a cationic electrodeposition coating composition. The present invention provides a method for producing an epoxy viscous agent for a cationic electrodeposition coating material, the method comprising: (1) an amine modification step in which an amine-modified epoxy resin is obtained by reacting an amine compound and a chain-extended epoxy resin that is obtained by extending a chain of a polyphenol polyglycidyl ether-type epoxy resin and has a material having a relative molecular weight of 100,000 or more in a proportion of 13.0-18.0 mass%, (2) a dispersion step in which a portion or the entirety of an amine group of the obtained amine-modified epoxy resin is neutralized with an acid and dispersed in an aqueous solvent, and (3) a high molecular weight obtaining step in which an obtained dispersion is mixed and reacted with a polyphenol polyglycidyl ether-type epoxy resin to obtain an epoxy viscous agent. Also provided is a cationic electrodeposition coating composition including said epoxy viscous agent.