ELECTRODEPOSITION COATING COMPOSITION AND ITS PREPARATION

• Main Authors: TANGVIJITSAKUL Pattarasai, WANG Lin, THEIL Hubert, XING Su Jie
• Format: Patent
• Language: English; Spanish
• Published: 20.05.2024
• Subjects: ADHESIVES; 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; 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 present invention provides a cathodic electrodeposition coating composition, which comprises (A) a cationic amino-containing epoxy resin, and (B) a blocked polyisocyanate having having neutralized amine, which is obtainable or obtained by a process comprising steps of (i) reacting a polyurethane prepolymer containing isocyanate groups with at least one blocking agent selected from oximes, pyrazoles and active methylene compounds, to provide a partially blocked polyisocyanate, (ii) reacting remaining isocyanate groups in the partially blocked polyisocyanate with an amine compound having having active hydrogen, to provide an amine-containing blocked polyisocyanates, and (iii) neutralizing the amine-containing blocked polyisocyanates with an acid and (C) a curing catalyst. The present invention also provides a process for preparing the cathodic electrodeposition coating composition, and coating bath for cathodic electrodeposition comprising a cathodic electrodeposition coating composition. La presente invención proporciona una composición de recubrimiento por electrodeposición catódica, que comprende (A) una resina epoxi que contiene un grupo amino catiónico, y (B) un poliisocianato bloqueado que tiene una amina neutralizada, que se puede obtener o se obtiene mediante un proceso que comprende las etapas de (i) hacer reaccionar un prepolímero de poliuretano que contiene grupos isocianato con al menos un agente bloqueante seleccionado entre oximas, pirazoles y compuestos de metileno activo, para proporcionar un poliisocianato parcialmente bloqueado, (ii) hacer reaccionar grupos isocianato restantes en el poliisocianato parcialmente bloqueado con un compuesto de amina que tiene hidrógeno activo, para proporcionar un poliisocianato bloqueado que contiene una amina, y (iii) neutralizar los poliisocianatos bloqueados que contienen amina con un ácido y (C) un catalizador de curado. La presente invención también proporciona un proceso para preparar la composición de recubrimiento por electrodeposición catódica, y el baño de recubrimiento para electrodeposición catódica que comprende una composición de recubrimiento por electrodeposición catódica.