Composite plastic signs - mfd as blank sheets incorporating latent photo-sensitive tamperproof colourants

Abstract

Abstract Signs or data panels incorporating a synthetic supporting sheet and transparent protective covers together with intermediate matrix zones contg. a photosensitive material which can develop contrasting colours or shades by selective exposure to radiation of different frequencies. Pref. the intermediate layers also incorporate a layer or zones of a magnetisable compsn. Pref. the support sheet is made of PVC, polyvinylaceto-chloride, PET, cellulose acetate or polystyrene. Pref. the protective films comprise PET, PVC, polyvinylacetate-chloride or complex polymers of esters with ethylene, or vinylidene chloride. Pref. the photosensitive agent is "DYLUX" (RTM-Du Pont de Nemours). Esp. for mfr. of data sheets having visual markings which must be tamper-proof, viz identity cards, credit cards, season tickets, or labels.

Inventors

No inventors recorded.

Bibliographic Details