| 摘要 |
1286061 Coating FARBENFABRIKEN BAYER AG 2 Jan 1970 [3 Jan 1969] 219/70 Heading B2E [Also in Division C3] Coatings are produced on substrates by applying thereto solid particles of a fusible binder, which crosslinks spontaneously on heating and has a softening point in the range 50-150‹C, and hardening the coating by heating above 130‹C. The binder used is the product obtained by reacting (a) a homopolymer or copolymer of an ethylenically unsaturated monomer containing a hydroxyl group with (b) an alkoxymethyl isocyanate having 1 to 18 carbon atoms in the alkoxy group or allyloxymethyl isocyanate. Suitable hydroxy monomers include mono- or bis-hydroxymethyl norbornene, phenylallyl alcohol, hydroxyalkyl esters of acrylic, methacrylic, fumaric or maleic acid, trimethylolpropane monoallyl ether and glycol monovinyl ether. The hydroxy monomers can be copolymerised with monomers which do not react with isocyanates, e.g. (meth) acrylate esters, styrene, alkylstyrenes, (meth) acrylonitrile, α-chloroacrylonitrile, vinyl acetate, vinylidene chloride, (meth) acrylamide and N-alkyl derivatives thereof, N-vinylacetamide, diacetone acrylamide and (meth) acrylic acid. Before being hardened the binder coating may be fused by heating at 50-150‹C. The binders may be admixed with pigments (e.g. titanium dioxide), extenders, fillers and plasticisers (e.g. dicyclohexyl phthalate). The binder can be applied with a spray gun (operated with compressed air) or it can be electrostatically sprayed; alternatively the article to be coated can be dipped in a fluidised bed of the binder. In Examples coatings are applied to steel panels. |
