Patent GB-1140368-A (GB)
Title: Manufacture of synthetic resin mouldings from liquid synthetic resins
IPC: B29C33/00
Filed: 1966-04-13
Abstract: 1,140,368. Moulding building elements; laminated building elements. S. R. BARNETTE. 13 April, 1966, No. 16210/66. Headings B5A and B5N. In a process for moulding articles having a multi-faceted surface, e.g. building elements, a liquid resin 19, Figs. 5 and 6, is caused to gel in contact with a moulding surface which comprises a multiplicity of sharp creases forming a multiplicity of irregular randomly disposed facets which define elevations and depressions. The said moulding surface may comprise a sheet or film which is applied to or receives the liquid resin and may be stripped from the moulded article. A roller 20 and wooden blade 14, Fig. 6, may be used to apply the creased sheet to the resin in a mould or on a conveyer in such a way as to expel air from under the sheet. A reinforcing preferably permeable fibre mat and/or a perforated core, e.g. a honey-comb, may be embedded in the article, Fig. 7. A mottled effect may be obtained by using differentially coloured resins for different areas which may be defined by resin grouting which may be removed and replaced by more resin. The mottling effect may be increased by combing. A design pattern may be given to the article by a preliminary dispersing of a liquid resin in the desired pattern on a film 25, Fig. 14, which is drawn-up as the resin shrinks. The design may be produced or accentuated by displacing selected surface areas of the article by the action of weighted pressing members 21, Fig. 32, which may be heated. The article may have multifaceted sheets on opposite surfaces, Fig. 37, or may be flat on one side, e.g. by casting in contact with a glass sheet which may be removed. If the glass is to remain it may be coated with an epoxy resin. Structural elements, e.g. tubes and/or spring-loaded securing means may be embedded in the article during moulding. The panel may be removed from the mould after gelling and cured in a shelved cabinet or further shaped on a surface which is given the desired shape, Fig. 41. A mould cavity defined by inner and outer cylinders is used to mould a pipe having multi-faceted inside and outside surfaces. The reinforcing mat may be woven or non-woven glass fibre, textile fibre or plastics fibre or may be strands of metal or a plastics film. If the creased sheet is applied to the resin a further layer of liquid resin may be cast thereon, Fig. 17. The creased sheet may be of a reflective material, e.g. a metal foil or a plastics film having a reflective coating, e.g. a metal coating. A composite moulding may be formed in two stages, the first stage resulting in reinforced layer having a partially embedded core which, in the second stage, is impressed on to a second reinforcing web embedded in a second layer. The resin may include a pigment or the pigment may be applied as a coating or in a separate film which may absorb ultra-violet radiation. Other ingredients may be a catalyst, a light-absorbent and a flame retardant. The casting surface may have discrete solid decorative or design elements, e.g. leaves, mother of pearl flakes, tinsel or butterflies placed thereon or such elements may be placed on the liquid resin layer. The multi-faceted sheet may be produced by manually or mechanically creasing a thin sheet. The casting resin may be a polyester, epoxy, polymethylmethacrylate, a plastisol copolymer of P.V.C. with polyvinyl acetate or polyvinylidene chloride. The creased sheet may be of polyvinyl fluoride, polyvinylidene fluoride, polyester, polyamide, polyethylene, polypropylene, P.V.C. or a copolymer of P.V.C. and polyvinyl acetate, oiled or waxed paper, aluminium foil or copper foil. Suggested materials for inserts are wood, plywood, particle board, foamed plastics. Suggested articles are ornamental panels, e.g. imitation stained glass, Fig. 2, room dividers, signs, windows, lamp shades and other lamp parts, Fig. 9, wall awnings and doors.