Patent GB-673129-A (GB)
Title: Coated sheet materials and processes for making the same
IPC: D04H13/00
Filed: 1949-11-23
Abstract: 673,129. Compound sheet materials. AMER-. ICAN VISCOSE CORPORATION. Nov. 23, 1949, No. 30054/49. Class 140. Coated fibrous sheet material suitable for artificial leather is made by adhering a film of thermoplastic material to a surface of a fibrous web consisting of carded fibres or fibres arranged in haphazard fashion and having thermoplastic fibres therein by pressing the film and web together under a pressure which only partly compresses the fibrous web, and simultaneously or subsequently pressing selected areas of the film to form depressed areas therein and to compress further the fibres beneath said selected areas, the film and the web being subjected during at least a portion of each pressing step to heat sufficient to render the film and the thermoplastic fibres in the web adhesive, the film and web being restored to the non-adhesive state, as by cooling, while the web is still compressed so as to form a permanent depressed design. The film may be mounted on a temporary backing sheet through which the pressure is exerted. The backing may be retained or removed before the embossing step. The film may be of thermoplastic resin, thermoplastic cellulose derivative, thermosetting resin in a thermoplastic state, or mixtures of thermoplastic and thermosetting resin in a thermoplastic state, e.g. polyvinyl chloride, vinyl chloride copolymerized with vinyl acetate or vinylidene chloride, polyamides, rubber, cellulose acetate, butyl cellulose, phenol- or ureaformaldehyde. Suitable temporary backings: are regenerated cellulose film, smooth paper;' and polished metal. The web contains non- adhesive fibressuch as cotton, wood pulp, wool, silk, hemp, flax, hair, fur, or regenerated. cellulose and a minor proportion of fibres, thermoplastic materials or of thermosetting materials in a thermoplastic state, e.g. vinyl chloride polymerized alone or with vinyl acetate, vinylidene chloride, or methyl methacrylate, polyvinylidene chloride, polystyrene, polymethyl methacrylate, polyvinyl acetal or butyral, polythene, polyamides, natural or synthetic rubber, phenol-formaldehyde resin, or cellulose acetate. The different fibres are mixed and formed into a web by depositing from a current of air on a perforated surface or by carding, garnetting, felting, or the papermaking process. The fibrous web may be heated before union with the film to bond fibres and give it coherence. As shown, a fibrous web 20 from a card or garnet machine passes between rollers 1, 2 which may be heated to cause some fibre-bonding to take place, and is pressed together with a thermoplastic film 3 on a temporary backing sheet 4 against a heated drum 6 by means of a tensioned endless belt 7 passing around rollers 8-11. After cooling the resulting unitary structure in a chamber 12, the backing sheet is removed by a stripping roller 13 and wound up at 16 while the coated fibrous sheet proceeds between an embossing roller 14 and a heated roller 15 and is immediately thereafter cooled by an air blast 17 and wound up at 18. The film may be applied to the temporary backing as a paste comprising a finely-divided vinyl resin in a volatile non-solvent liquid and a minor proportion of solvent. Specification 648,816 is referred to.