Abrasion-resistant coating composition e.g. for painting cars, buildings, furniture and white goods comprises hard, hollow micro-particles concentrated at surface of the coating

摘要

A resin-based coating composition (I) contains at least 1 wt.% (based on solids in I) of hollow micro-particles (II), at least 30 wt.% of which consists of material with a Mohs hardness of more than 5.5, the particles being so light and the composition being so mobile that the particles can concentrate at or move on the surface of a liquid film without sinking into it. A surface-coating composition (I), especially for metals, alloys, wood, timber products, plastics, polymer-containing materials and/or composites, e.g. as an anti-wear coating, the upper layer of a multi-layer system or for coating films, comprises a dispersion containing resin and optionally crosslinker, photoinitiator(s), additive(s), solvent, reactive diluent and/or water. Composition (I) contains micro-particles consisting of or including hard, hollow micro-particles (II), at least 30 wt.% of which consists of material(s) with a Mohs hardness of more than 5.5, in amounts of at least 1 wt.% (II) based on total solids in (I), the particles (II) being so light and the composition (I) being so mobile that at least part of (II) is able to concentrate at the surface of a liquid film and/or to move on the surface without sinking into the film. Independent claims are also included for: (1) a method for coating surfaces by applying dispersion (I) with a viscosity which enables at least part of the hard particles (II) to concentrate in the surface of the liquid film thus formed (2) substrates coated with (I) so that the particles (II) are distributed over the surface in an essentially homogeneous manner (3) dried and optionally hardened compositions (I), especially clear varnish, matt paint, colored paint, anti-wear coatings or anti-corrosion coatings, which show an abrasion loss of less than 6 mg in the Taber test over 1000 revolutions with a CS-17 abrasive wheel (corundum particles) under a load of 1000 g.