Tamper and copy protected documents
US5454598A · kind A · utility
Inventor
Key dates
| Filing date | Apr 19, 1993 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | Apr 19, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB42D2033/22
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A tamper and copy protected document includesn array of fine blind holes (or, alternatively, of fine perforations) impressed on the document in areas where specific information is to be imprinted. Imprinting of information on the array of holes (or perforations) results in penetration of ink into the fibrous interior of the document, between its surfaces. A resinous coating, applied over the array and over the imprinted information, also penetrates into the interior to encapsulate the ink. A copy protected document is produced by imprinting it with specific alphanumeric information which includes perforations in the imprinted characters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.