Coating compositions for precoated metal sheets

• Main Authors: FUKUDEN, KOICHI, KENNY, JOHN, YUASA, KOUICHI, MORIHARA, MIWA, SAWADA, HARUHIKO
• Format: Patent
• Language: English; French; German
• Published: 04.02.1998
• Edition: 6
• Subjects: ADHESIVES; 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; POLISHES; USE OF MATERIALS THEREFOR; WOODSTAINS

A coating composition suitable for use in precoated metal sheets comprising: (A) a hydroxyl group-containing film-forming resin having a hydroxyl number of from 5 to 100; (B) 0.5 to 10 parts by weight as solids of a first curing agent per 100 parts by weight as solids of said film-forming resin (A), said first curing agent having a solubility parameter lower than the solubility parameter of said film-forming resin (A) by at least 0.5; (C) 10 to 50 parts by weight as solids of a second curing agent per 100 parts by weight as solids of said film-forming resin (A), said second curing agent having a solubility parameter not lower than by 0.5 or higher than the solubility parameter of said film-forming resin (A); (D) 0.1 to 2.0 parts by weight of an acid catalyst per 100 parts by weight as solids of said film-forming resin (A) for promoting the reaction between said film-forming resin (A) and said first curing agent (B); and (E) an amount in excess for neutralizing said acid catalyst (D) of a volatile amine having a boiling point not lower than 40 DEG C but lower than the baking temperature of the composition.