04711690 is referenced by 87 patents and cites 17 patents.

The multilayer identification card comprises several synthetic layers compounded by the effects of heat and pressure. An inside interface of at least one of these layers exhibits depressions which are filled with the material of the adjacent layer during the laminating process. The adjacent layers are selected in such a way that they are of different transparency. Thus a light and shadow effect is produced in incident light which is reversed in transmitted light.

Title
Method for making an identification card having features for testing in incident and transmitted light
Application Number
521264
Publication Number
4711690
Application Date
December 18, 1985
Publication Date
December 8, 1987
Inventor
Yahya Haghiri Tehrani
Munich
DE
Agent
Stevens Davis Miller & Mosher
Assignee
GAO Gesellschaft fur Automation und Organisation mbH
DE
IPC
B32B 27/00
B32B 5/00
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