Patent GB-1088005-A (GB)
Title: Decorative materials
Inventor: COBB LESLIE HAMILTON
IPC: B32B15/08
Filed: 1964-10-02
Abstract: 1,088,005. Laminates and laminating. IMPERIAL CHEMICAL INDUSTRIES Ltd. Sept. 15, 1965 [Oct. 2, 1964], No. 40148/64. Heading B5N. In a process in which decorative materials are produced by delaminating a laminate comprising two films of plastics material with a metal film 0.0004 to 0.0008 mil thick between them, the angles between the laminate and the delaminated films of plastics material are so varied that a portion of the metal film is retained by each plastics film in turn, thus resulting in a series of spaced transverse metallic stripes on each plastics film. In one embodiment, Fig. 4, rolls 11 supply the laminate to be delaminated and rolls 12, 13 draw off the two delaminated plastics films. Before delaminating the laminate is fed between a pair of oscillating rollers 14<SP>1</SP>, 14<SP>11</SP> which vary the angle between the laminate and each drawn-off film. At its minimum the angle between the laminate and one of the films is preferably less than 45 degrees. The plastics films are of e.g. cellulose acetate, regenerated cellulose, polyvinylidene chloride, polyethylene terephthalate and polypropylene, and are preferably biaxially oriented and heat set films of one of the latter two materials. One of the plastics films may be in the form of a coating which when carried by a plastics or fibrous backing, e.g. of paper or fabric, acts as an adhesive. The adhesive is a vinyl polymer or copolymer, e.g. a copolymer of vinyl chloride and vinyl acetate, which may be modified by partial hydrolysis of the polyvinyl acetate to polyvinyl alcohol or by the inclusion of maleic anhydride as a further copolymer. Alternatively the adhesive is a polyester, e.g. a co-polyester obtained from a glycol and a mixture of dibasic acids, applied in solution in e.g. methyl ethyl ketone, acetone, ethyl acetate, or a mixture of solvents. The metallic layer is preferably of aluminium but zinc, silver, gold, lead, cobalt, platinum, tungsten, tantalum, molybdenum, nickel; or chromium may be used. One or both of the plastics layers may be dyed or pigmented. In one embodiment the laminate comprises layers of polyethylene terephthalate, aluminium, adhesive, and a further layer of polyethylene terephthalate or paper, the laminate being delaminated as shown in Fig. 4. To prevent oxidization of the exposed metallic stripes a film-carrying adhesive layer may be hot-pressed on to each delaminated plastics film. In a further embodiment the starting laminate comprises a central metal layer to which outer layers of polyethylene terephthalate are secured by adhesive. After delaminating the plastics layers may be coated and rejoined to form a laminate with their metallic stripes coincident. In a further embodiment the starting laminate comprises a central layer of polyethylene terephthalate having a layer of metal on each side and outer layers of regenerated cellulose secured to the metal layers by adhesive. One of the metal layers is divided by apparatus as shown in Fig. 4, and the delaminated films coated before the thicker film is delaminated along the second metallic layer by a second apparatus, thus producing two more plastics films which are again coated. The decorative films may be slit into threads or used for packaging.