Browse Prior Art Database

IDENTIFICATION TECHNIQUE FOR TRACING COPIES TO A PARTICULAR COPIER

IP.com Disclosure Number: IPCOM000024353D
Original Publication Date: 1980-Jun-30
Included in the Prior Art Database: 2004-Apr-02
Document File: 2 page(s) / 71K

Publishing Venue

Xerox Disclosure Journal

Abstract

Traditional forms of documentation, whether typewritten or handwritten, carry identifiable signatures due to a combination of paper type, handwriting type, pen and typewriter characteristics, etc. Xerographic copies are more difficult to identify since the paper and toner tends to be standardized to one of a few types.

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XEROX DISCLOSURE JOURNAL

Proposed Classification
U.S. C1. 252/408 Int. C1. C09k 3/00

David E. Damouth

Traditional forms of documentation, whether typewritten or handwritten, carry identifiable signatures due to a combination of paper type, handwriting type, pen and typewriter characteristics, etc. Xerographic copies are more difficult to identify since the paper and toner tends to be standardized to one of a few types.

A technique for tracing copies is disclosed wherein a small proportion of color coded tag particles are mixed with standard xerographic toners. The tag particles charge and develop in a manner similar to the toner. All toner is coded systematically by date, production batch, etc. It is then possible to examine a xerographic copy with a standard optical microscope and rapidly determine the serial number of the toner batch. It is necessary that the tag particles be compatible with standard xerographic developers. This means that the micro- particles must tribocharge in a manner similar to the toner and achieve a charge of approximately the same magnitude in order to insure that toner and microparticles develop out at approximately the same proportional rates.

Concentrations of below one percent are sufficient to allow rapid location of a particle with the right orientation for a color code to be visually read under a microscope. As additional identification techniques, the tag particles could be added to the copy paper during its manufacture as well...