| 摘要 |
<p>1373498 Coating process E T E R N I TWERKE LUDWIG HATSCHEK and UOBSA 21 Oct 1971 [30 Oct 1970] 49022/71 Heading B2E [Also in Division C3] Decorative and/or protective coatings on water-absorbant substrates are produced by mixing an aqueous dispersion of a saturated water-insoluble synthetic resin with a polymerisable organic liquid capable of swelling the synthetic resin particles, coating the substrate with the resultant mixture, and then hardening the coating by free radical polymerisation and/or free radical graft copolymerisation of the organic liquid effected thermocatalytically, or by irradiation with ultra violet light, or by exposure to high energy rays. (Graft copolymerisation is stated to occur as the major reaction when hardening is effected with high energy radiation.) Examples of the waterinsoluble synhtetic resins are vinyl chloride polymers and copolymers (e.g. with vinyl acetate), acrylic or methacrylic polymers and copolymers, styrene polymers and copolymers (e.g. with butadiene or acrylic acid), chlorinated rubber and polyurethanes. Suitable polymerisable liquids include vinyl acetate, vinylidene chloride, vinyl sulphonic acid, acrylic acid, acrylonitrile, acrylic or methacrylic esters, styrene, vinyl carbazole, esters and ethers of allyl alcohol, and maleic acid and its derivatives. The liquid may comprise a higher boiling polymerisable component to prevent evaporation losses, e.g. hydroxyalkyl (meth) acrylates and other (meth)acrylic esters of glycols or other polyalcohols, and allylic esters of polybasic acids. Thermocatalytic hardening may be effected with a peroxide, azo compound or redox system. With ultraviolet radiation, a sensitiser such as benzoin, benzophenone, anthraquinone and their derivatives or certain sulphur- or halogen-containing compounds is normally used. The preferred form of high energy radiation is electron radiation. Optional components in the coatings include pigments, finely divided fillers and silicones. Examples of water-absorbant substrates are wood (e.g. plywood), fiberboard, cardboard, paper; textiles, concrete, asbestos cement and natural stone. The coating mixture can be applied to the substrate by painting, pouring on, or spraying.</p> |
