COMPOSITION DE REVETEMENT D'UNE HAUTE TENEUR EN MATIERES SOLIDES CONSTITUEE D'UN MELANGE D'UN POLYMERE ACRYLIQUE DE POIDS MOLECULAIRE PEU ELEVE, D'UN POLYMERE ACRYLIQUE DE POIDS MOLECULAIRE MOYEN ET D'UN AGENT DE RETICULATION MELAMINE ALCOYLEE, ET SUBSTRATS REVETUS D'UNE TELLE COMPOSITION

L'INVENTION SE RAPPORTE AUX PRODUITS DE FINITION, TELS QUE DES PEINTURES.ELLE CONCERNE UNE COMPOSITION DE REVETEMENT D'UNE HAUTE TENEUR EN MATIERES SOLIDES COMPRENANT UN LIANT A CONSTITUANTS FILMOGENES ET UN VEHICULE LIQUIDE NON AQUEUX; LES CONSTITUANTS FILMOGENES ETANT FORMES DE A UN POLYMERE ACRYLIQUE AYANT UN POIDS MOLECULAIRE MOYEN EN NOMBRE DE 5000-20000, ET B UN POLYMERE ACRYLIQUE AYANT UN POIDS MOLECULAIRE MOYEN EN NOMBRE DE 500-7500, LES POLYMERES A ET B AYANT UNE TENEUR EN GROUPES -OH DE 2-10 ET DERIVANT DE METHACRYLATE DE METHYLE, D'UN METHACRYLATE OU D'UN ACRYLATE D'ALCOYLE ET D'UN ACRYLATE OU D'UN METHACRYLATE D'HYDROXYALCOYLE; LA DIFFERENCE DE POIDS MOLECULAIRE ENTRE A ET B ETANT D'AU MOINS 3000; ET C UN AGENT DE RETICULATION FORMALDEHYDE-MELAMINE ALCOYLEE; LA COMPOSITION CONTENANT EN PLUS UN CATALYSEUR ACIDE.APPLICATION A LA FINITION D'AUTOMOBILES, CAMIONS, ETC. The high solids coating composition contains at least 50% by weight of a binder of film-forming constituents in which the constituents are of (A) a medium molecular weight acrylic polymer that has a number average molecular weight of about 5,000-20,000, a hydroxyl content of at least 2% by weight, a glass transition temperature of about -20 DEG C. to +25 DEG C., and is of an alkyl methacrylate, a hydroxy alkyl acrylate or a hydroxy alkyl methacrylate, and optionally, an alkyl acrylate or styrene; (B) a low molecular weight acrylic polymer that has a number average molecular weight of about 500-7,500 a hydroxyl content of at least 2% by weight, a glass transition temperature of about -20 DEG C. to +25 DEG C., and is of an alkyl methacrylate, a hydroxy alkyl acrylate or a hydroxy alkyl methacrylate, and optionally, an alkyl acrylate and styrene; (C) an alkylated melamine formaldehyde cross-linking agent; and an acid catalyst; the composition is particularly useful as an exterior finish for automobiles, trucks, airplanes and can be used as an appliance finish and for coil coatings.