Patent GB-1199195-A (GB)
Title: Chemically Embossed Surface Coverings Using Barrier Film
IPC: D06N7/00
Filed: 1967-08-16
Abstract: 1,199,195. Embossing thermoplastics material. ARMSTRONG CORK CO. 16 Aug., 1967 [16 Aug., 1966], No. 37818/67. Heading B6J. [Also in Divisions B1-B2] An embossed thermoplastic sheet is prepared by (1) blending in the absence of a blowing agent activator (a) a vinyl resin, (b) a plasticizer resin, and (c) a blowing agent which decomposes when heated to a temperature above the glass transition temperature of the vinyl resin and below the decomposition temperature of the resin, (2) forming the blending to a sheet, (3) applying to the sheet in a design a barrier layer which will either prevent penetration of activator for the blowing agent into the sheet or destroy the effectiveness of such an activator, (4) applying over the surface of the sheet, at least in those areas that are not screed by the barrier layer a liquid resin containing an activator for the blowing agent so that the activator penetrates the sheet and produces in those parts of the sheet that are not screened by the barrier layer, a blowing system comprising the blowing agent and the activator which accelerates the rate of decomposition of the blowing agent, and (5) heating the thus treated sheet to decompose the blowing system. The vinyl resin may be a polymer or copolymer of vinyl chloride. Comonomers specified are vinyl esters, alkyl substituted vinyl esters or acrylic compounds, such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylic acid and methacrylic acid and acrylates or methacrylates. The copolymer may also contain units of maleic anhydride. The plasticizer may be an organic ester type plasticizer or a phosphate ester type plasticizer of which many are specified. Numerous blowing agents are specified. The blowing agent may be present in amount 0.5 to 50% of the weight of the vinyl resin. The compositions may also contain a pigment, dye, and up to 20% of the total weight of the blend of a granular filler such as clay, limestone or a silicate. Heat and light stabilizers in amount of not more than 3% of the total blend may also be present. The sheet may be made by applying a blend to a backing material or on to a strippable carrier, such as by doctoring, roll coating or knife coating. The backing may be a conventional floor covering, a steel or rubber belt or a release coated paper of felt. The barrier layer may be a film of thermoplastic resin, metal foil, resin saturated paper, thin dry laid sheet saturated with a resinous binder, a cellulosic tape or film or a thin sheet of rubber having openings cut therein. Alternatively the barrier layer may take the form of pieces of sheet material laid on selected portions of the sheet. The barrier layer may also be a layer of polymer printed on to the sheet. The thermoplastic film used as the barrier layer may be of polyvinyl chloride, vinyl chloride/vinyl acetate copolymer or a polyacrylate film. The barrier layer may also be a thermosetting ink based on an epoxy-polyamide system, a phenol-formaldehyde system or an acrylic-epoxy system. The barrier layer may also be a chemical that reacts with the activator and destroys its effectiveness. Such compounds may be a chelating agent, a Lewis acid, stannous stearate or stannous maleate, phosphoric acid or a barium-sodium organophosphate. The activator may be a metallic soap, or a zinc, lead or cadmium salt of naphthenic or phthalic acid. The metal of the metallic soap may be zinc, lead or cadmium, and a fatty acid portion of the soap may contain 7-18 carbon atoms. The activator may be applied to the sheet in solution or suspension in a liquid that will penetrate the material of the sheet, whilst the liquid may be solvent or a plasticizer for the vinyl resin or a mixture of a solvent and a plasticizer.