GB1159119A - Polymerisable Paint Binders and a Coating Method Employing such Binders - Google Patents

Abstract

1,159,119. Coated surfaces. FORD MOTOR CO. Ltd. 9 Aug., 1966 [13 Aug., 1965], No. 35513/66. Heading B2K. [Also in Division C3] Substrates (e.g. of wood or metal) are coated by applying thereto a film of paint binder comprising a film-forming solution of a vinyl resin in one or more liquid vinyl monomers copolymerisable with the resin by ionising radiation, the resin having a molecular weight in excess of about 1000, containing 0.5-3 olefinic unsaturation units per 1000 of the numerical value of the molecular weight, and at least a major proportion by weight of the resin being derived from acrylic monomers; and subjecting the applied film to ionising radiation to copolymerise the resin and vinyl monomers. (The term "acrylic monomers" is used to include α,#-monoethylenically unsaturated monocarboxylic acids and esters thereof, e.g. acrylic, methacrylic or chloroacrylic acid and their esters.) The paint binder may, if desired, contain a pigment (e.g. TiO 2 ,) and/or filler. The ionising radiation is preferably an electron beam but other high energy particle radiation or ionising electromagnetic radiation may be used. The film of binder may be applied by spraying, brushing, roll coating, flow coating, or by the silk screen process, preferably in a depth of 0.1-4.0 mils. Suitable liquid vinyl monomers include vinyl hydrocarbons such as styrene and acrylic monomers such as methyl methacrylate. The vinyl resin component of the paint binder is preferably one obtained by copolymerising monomers (acrylic or mainly acrylic) to give a polymer having reactive groups such as hydroxyl or glycidyl groups, and reacting said polymer with an ethylenically unsaturated monomer containing a complementary reactive group, e.g. a carboxyl group, whereby unsaturation is introduced into the polymer; particularly suitable vinyl resins are reaction products of {a) a copolymer of methyl methacrylate, ethyl acrylate, glycidyl methacrylate and, optionally, styrene with (b) methacrylic acid. The cured films are wear- and weather-resistant and can be applied for decorative purposes.