IE33160B1 - A method of manufacturing a backer for use in the manufacture of leather substitutes - Google Patents

Abstract

1,273,386. Laminates. STATNI VYZKUMNY USTAV KOZEDELNY. 15 July, 1969 [16 Aug., 1968], No. 35525/69. Heading B5N. [Also in Division D2] A method of making a backer for use in the production of leather substitutes comprises applying a layer of swollen, untanned, collagencontaining fibrous material to one or both sides of a textile screen, treating the structure with a salt (e.g. Na Cl) to deswell the collagen fibres, pressing the structure, e.g. stepwise, needle punching the structure e.g. while it is still wet, tanning it, and applying a second textile screen to the exposed face of the collagen layer. Alternatively, before deswelling of the fibres, a natural or synthetic fibrous web may be applied to one or both faces of the structure. The textile screen, which may be of woven, knitted or non-woven fabric, and web may be of polyamide, polypropylene, polyester, polyacrylonitrile, staple regenerated cellulose, cotton, wool or flax fibres or mixtures of these. The collagen fibre material is prepared from split hides or waste from the machine treatment of hides, may be mixed with textile fibres or ground shavings of chrome-tanned leather, and may contain a non-ionic or cation-active fatliquoring agent or a binder such as latex, polyacrylate, polyisocyanate or their monomers. The salt may be added as a saturated solution or in finely powdered form. The tanning may be with a salt of Cr, A1 or Zr, or with formaldehyde and the backer is then preferably dried. After drying, the backer may be impregnated with a polyurethane or a latex. A ready-made artificial grain sheet may then be applied, or the backer may be buffed and finished by a conventional leather finish. [GB1273386A]