| 摘要 |
1337276 Embossing FISONS Ltd 1 June 1971 [11 June 1970] 28434/70 Heading B6J [Also in Divisions B2 and C3] A thermoplastic polymer is embossed by selective expansion by forming into sheet form an expandable mix containing the polymer, a blowing agent and at least one tin compound, applying to selected areas of the sheet surface a composition containing a kicker for the blowing agent and heating so that in those areas in contact with the kicker, the blowing agent is decomposed to a greater degree and the sheet thereby differentially expanded. The polymer may be polycaprolactam, polyaminoundecanoic acid, a terephthalate polyester, polyethylene, polypropylene, polymethylmethacrylate, polystyrene, PVC or a copolymer of vinyl chloride with vinyl acetate, vinylidene chloride, acrylic acid or styrene. The tin compound may be dibutyl tin maleate, a dialkyl tin laurate, a thiotin compound or a tin mercaptide and the blowing agent is especially azodicarbonamide. Numerous kickers are specified but it may especially be zinc octoate or nitrate. The kicker composition consists of a mixture of a solution or dispersion of the kicker and a solution or dispersion of a film former or binder resin (a number of these being specified) and a dye or pigment. Before printing, the expandable mix is gelled usually by heating at 100-150‹C for 2À5-0À5 minutes. The mix may be extruded, cast, calendered or spread as a plastisol on to a backing of resinous material, woven fabric, impregnated felt or a release paper coated with silicone, alginate or casein. The printed and gelled layer may be coated with a further PVC layer prior to expansion. The expanded material may be used in the manufacture of flooring, wall and ceiling coverings. |
