ANTI-GRAFFITY POWDER COATING COMPOSITION

• Main Authors: MARELLI, ERNESTO, RODRIGUEZ-SANTAMARTA, CARLOS, REKOWSKI, VOLKER
• Format: Patent
• Language: English; French; German
• Published: 23.09.2009
• 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 present invention provides an anti-graffiti powder coating composition comprising (A) 30 to 80 wt% of a mixture of at least one polyester resin A having a hydroxyl number in the range of 30 to 60 mg KOH/g, a weight average molar mass Mn in a range of 3100 to 5000 and a glass transition temperature Tg of 40 to 60 °C and at least one polyester resin B having a hydroxyl number in the range of 250 to 350 mg KOH/g, a weight average molar mass Mn in a range of 2000 to 3000, (B) 10 to 40 wt% of at least one hardeners selected from the group consisting of diisocyanates, polyisocyanates and urethdiones, and (C) 0,01 to 40 wt% of at least one coating additive, pigment and/or filler, the wt% being based on the total weight of the powder coating composition. The powder coating composition of this invention are coating compositions providing a very good anti-graffiti performance of the coatings for a long time period besides good coating properties, particularly, high exterior durability and chemical resistance as well as a gloss-control of the coated surface, to receive, e.g. matt to semi-matt coatings.