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EP0271673A1
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Multi-layer document
Assignee: Siemens Building Technologies AG
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Filing: 1987-10-23
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Granted: —
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Expires: 2007-10-23
Abstract
Abstract A multi-layer document consists of two protective layers (1; 2) and an intermediate information layer (3). This information layer (3) contains at least one water sensitive layer (6), which is applied, for example in a pattern, on a carrier layer (2), as protection against fraudulent copying of the microscopic optical markings (4) embedded therein, and at least one optically active intermediate layer (5). <IMAGE>
Inventors
- 👤 Eva Blazsò
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 22:03
CPC Classifications
B; B42; B42D; B42D25/00; B42D25/30; B42D25/324; B42D25/40; B42D25/405; B42D25/425; B42D25/45; G; G06; G06K; G06K19/00; G06K19/06; G06K19/08; G06K19/10; G06K19/14; G06K19/16; G07; G07F; G07F7/00; G07F7/08; G07F7/086; B42D2033/04; B42D2033/14; B42D2033/32; B42D2035/02; B42D2035/14; B42D2035/24; B42D2035/44; B42D25/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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