JPS6410284A - Film laminate with disabled copy - Google Patents

Abstract

PURPOSE: To make copying infeasible and to make understanding possible in exactly the same manner as usual by visual sensation by superposing and bonding two sheets of thermoplastic polymer films molded to a specific rugged shape in such a manner that the rugged surfaces coincide with each other. CONSTITUTION: The one plane of the transparent thermoplastic polymer film having 30 to 100 micron thickness is molded to the rugged shape of a saw tooth shape or the shape resembling the same in plural directions intersecting with each other at an arbitrary angle. Two sheets of such films 1, 3 with these surfaces faced on the inner side are superposed on each other. An extremely thin air layer is interposed in the spacing between the films and substantially all of the incident light rays from any surfaces are totally reflected and, therefore, the copying of documents by a third person's illicit camera or a copying device is entirely impossible and the contents of articles are readable in exactly the same way as usual when these contents are to be read by the visual sensation.