Browse Prior Art Database

DOCUMENT SECURITY SYSTEM

IP.com Disclosure Number: IPCOM000022944D
Original Publication Date: 1976-May-31
Included in the Prior Art Database: 2004-Mar-27
Document File: 2 page(s) / 184K

Publishing Venue

Xerox Disclosure Journal

Abstract

A document security system is provided in which all copiers in a users premises have the same actinic response. The only copy paper available for use contains a pre~printed pattern. The copier is unable to discriminate between the pre-printed pattern and the information pattern.

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At least one non-text object (such as an image or picture) has been suppressed.
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Page 1 of 2

XEROX DISCLOSURE JOURNAL

DOCFJMENT SECtJRITY SYSTEM Proposed Classification

J. M. Randall 15,5. Cl. 96/42
mt. ci. G03c 5/04

A document security system is provided in which all copiers
in a users premises have the same actinic response. The
only copy paper available for use contains a pre~printed
pattern. The copier is unable to discriminate between
the pre-printed pattern and the information pattern.

For example, a copy prepared by placing a black toner image
on paper containing a pre~printed red pattern is visibly
useful, However, such a copy cannot itself be usefully
copied by a copier which Ttsees~ red and black as being
the same color,

When it is attempted to make second generation copies
(copies of properly made first copies), the document
security produces an image of substantially constant
density comprised of the pre~printed background and the
copied image. Such an image is not visibly useful.

An additional safeguard against the information and the
background being printed at visibly different densities
can be provided by the use of a densitometer or a potenti~-
ometer to prevent transfer or development, respectively, of
second generation copies which have undesirably high density
variables,

Volume 1 Number 5 May 1976 21

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22 XEROX DISCLOSURE JOURNAL

Volume 1 Number 5 May 1976

[This page contains 1 picture or other non-text object]