Patent GB-1149246-A (GB)
Title: Method for coating surfaces
Inventor: MARRIOTT ANTHONY GEOFFREY
IPC: D06N3/04
Filed: 1965-09-30
Abstract: 1,149,246. Coated sheet material. DUNLOP CO. Ltd. 15 Sept., 1966 [30 Sept., 1965], No. 41666/65. Addition to 1,105,481. Heading B2E. Articles having a surface consisting at least in part of a natural or synthetic rubber composition are coated by applying to the surface an interlayer of a composition of a graft polymer of a vinyl monomer and a natural or synthetic rubber, gelling the composition of the graft polymer, applying to the gelled composition a solution or emulsion of a polyacrylate whilst the graft polymer composition is still wet, drying the gelled composition containing the polyacrylate and applying to the interlayer an outer layer of an aqueous polymeric composition. The polyacrylate may be ammonium polyacrylate, which may be applied in the form of an aqueous solution, an acrylic polymer e.g. a polymer of methyl methacrylate with one or more acrylic or non-acrylic monomers, examples of which are given. The solution or emulsion of a polyacrylate may be applied by spraying. The composition of a graft polymer may be gelled by heating such as by subjecting the composition to live steam, for example, for three minutes. The gelled composition containing the polyacrylate may be dried by heating at 70‹C. The aqueous polymeric composition may be a composition of acrylic polymer e.g. a polymer of methyl methacrylate with one or more different acrylic or non acrylic monomers, examples of which are given, or nitrocellulose. The vinyl monomer may be an alkyl acrylate or methacrylate e.g. ethyl acrylate or methyl methacyrlate, acrylo nitrile, acrylamide, vinyl pyridine, styrene, vinyl ester, or vinylidene compound. The graft polymer may comprise a backbone chain of natural or synthetic rubber e.g. copolymers of butadiene and styrene, acrylonitrile or methyl isopropyl ketone, or polybutadiene. The graft polymer may be prepared by subjecting the vinyl monomer to ionising radiation in the presence of a rubber latex, or by stirring the vinyl monomer with a rubber latex in the presence of an initiator system, examples of which are given. The graft polymer may contain from 5 to 50% by weight of polymer units derived from the vinyl monomer. The coatings may be applied to the surface of leather-like sheet material comprising a textile web bonded with a natural or synthetic rubber composition. Suitable sheet material comprise a consolidated mat interpenetrated crimped continuous filaments bonded together with a resinous or elastomeric bonding agent (as described in Specification 989433); a mat of interpenetrated crimped continuous filaments having a non woven layer of unspun staple fibres needled on to or otherwise adhered to at least one surface, the non woven layer of unspun staple fibres being impregnated with a resinous or elastomeric bonding agent (as described in Specification 1042028); or a consolidated mat of interpenetrated crimped continuous filaments bonded together with a resinous or elastomeric bonding agent having a woven fabric bonded to one surface of the mat with a resinous or elastomeric bonding agent, and a surface layer of a resinous or elastomeric composition on that surface of the woven fabric which is remote from the mat (as described in Specification 1,105,483). Examples of bonding agents are given. A particularly suitable sheet material comprises a web of crimped continuous nylon yarns with or without a layer of non- woven polypropylene staple fibres needled on to one of its surfaces using a natural rubber latex as impregnant; the surface of the sheet material may be reinforced and smoothed by the application of a rubber latex composition.