Patent GB-726657-A (GB)
Title: Improvements in or relating to impregnated sheet materials and to compositions suitable for use in preparing the same
IPC: D06M15/693
Filed: 1951-05-22
Abstract: A mixture of rubber and a novolak resin together with sufficient curing agent (e.g. hexamine) to cause the resin to cure on heating is used to impregnate a fibrous base material. The composition may contain 1-9 parts (by weight of solids) of rubber to 3 parts of resin.  The novolak resin may be dissolved with the hexamine in ethyl acetate to give a 50 per cent solution which may be emulsified in water.  The rubber latex may be stabilized by means of a solution containing urea and casein as in Specification 674,885.  The two compositions may be mixed as required, and the resultant solution used to impregnate cotton bandage.  Motor vehicle upholstery may be made by placing strips of the impregnated material on a backing sheet of fibre board or tinplate, and covering with a layer of wadding following with a layer of display material such as leather cloth. The assembly is pressed in a press having a flat lower platen and ribbed upper platen giving the finished article a quilted appearance. In an example a novolak resin is dissolved, together with 10 per cent of its weight of hexamine, in ethyl acetate, and the resultant solution emulsified in water with the aid of casein and an emulsifying agent.  A stabilizer for rubber latex is prepared by reacting urea and casein in water, and when reaction has ceased, adding ammonia and glycine.  This is mixed with rubber latex made alkaline with ammonia and formaldehyde added in amount to leave an excess after reacting with the ammonia present.  The two solutions are mixed to give a composition containing a rubber: resin ratio of 2 : 1 by weight.  Cotton bandage is impregnated with this composition and air dried.  Specification 684,687, [Group V], also is referred to.ALSO:A mixture of rubber and a novolak resin together with sufficient curing agent (e.g. hexamine) to cause the resin to cure on heating is used to impregnate a fibrous base material.  The composition may contain 1-9 parts (by weight of solids) of rubber to 3 parts of resin.  The novolak resin may be dissolved with the hexamine in ethyl acetate to give a 50 per cent. solution which may be emulsified in water.  The rubber latex may be stabilized by means of a solution containing urea and casein as in Specification 674,885. The two compositions may be mixed as required, and the resultant solution used to impregnate cotton bandage.  Motor vehicle upholstery may be made by placing strips of the impregnated material in a backing sheet of fibre board or tinplate, and covering with a layer of wadding following with a layer of display material such as leather cloth.  The assembly is pressed in a press having a flat lower platen and ribbed upper platen giving the finished article a quilted appearance.  In an example a novolak resin is dissolved, together with 10 per cent. of its weight of hexamine, in ethyl acetate, and the resultant solution emulsified in water with the aid of casein and an emulsifying agent.  A stabilizer for rubber latex is prepared by reacting urea and casein in water, and when reaction has ceased, adding ammonia and glycine.  This is mixed with rubber latex made alkaline with ammonia and formaldehyde added in amount to leave an excess after reacting with the ammonia present.  The two solutions are mixed to give a composition containing a rubber: resin ratio of 2 : 1 by weight.  Cotton bandage is impregnated with this composition and air dried.  Specification 684,687 also is referred to.