摘要 |
A durable holographically imaged paper, plastic film or other product is produced by embossing the image into a thermoplastic coating thereon which comprises plastic pigment particles. The plastic pigment particles are preferably hollow but may be solid. The coating preferably also comprises a thermoplastic polymer or copolymer, for example a copolymer of vinyl acetate and versatic acid, an acrylic polymer, a styrene-acrylic or other acrylic copolymer, a vinyl chloride-vinyl acetate-ethylene terpolymer, a polyvinyl acetate or a polyvinyl alcohol. Preferably, the polymer or copolymer has a glass transition temperature (Tg value) in the range 20° C. to 110° C. The thermoplastic coating may also contain inorganic pigments, for example precipitated calcium carbonate (PCC), ground natural calcium carbonate, or kaolin or other clays, and/or a starch binder. Embossing is preferably carried out directly on the thermoplastic coating by means of a holographically engraved shim. |