Global Patent Index - EP 0539974 A1

EP 0539974 A1 19930505 - Method for preventing color copying of documents.

Title (en)

Method for preventing color copying of documents.

Title (de)

Verfahren zur Verhinderung des Farbkopierens von Dokumenten.

Title (fr)

Méthode pour empêcher la copie couleur de documents.

Publication

EP 0539974 A1 19930505 (EN)

Application

EP 92118496 A 19921029

Priority

IL 9993091 A 19911101

Abstract (en)

A method of producing a certificate on a substrate which is difficult to reproduce using color copiers including the steps of printing a first portion of the certificate in a first color and printing the second portion of the certificate in a second color, wherein the first and second portions have substantial color contrast in the original and, when reproduced using conventional color copiers, have substantially the same color. Preferably, the step of printing the second portion includes printing with a fluorescent ink.

IPC 1-7

G03G 21/00

IPC 8 full level

G03G 21/04 (2006.01)

CPC (source: EP)

G03G 21/043 (2013.01)

Citation (search report)

  • [X] EP 0428828 A2 19910529 - JUNG BAYROPA GMBH [DE]
  • [AD] US 4325981 A 19820420 - SUGIURA TAKEO, et al
  • [AD] US 4118122 A 19781003 - REES JAMES D, et al
  • [A] US 4281921 A 19810804 - VAN AUKEN JOHN A
  • [A] GB 2139955 A 19841121 - GEN ELECTRIC PLC
  • [AD] US 3713861 A 19730130 - SHARP J
  • [X] PATENT ABSTRACTS OF JAPAN vol. 4, no. 70 (P-12)(552) 23 May 1980 & JP-A-55 036 873 ( DAINIPPON INSATSU K.K. ) 14 March 1980
  • [A] PATENT ABSTRACTS OF JAPAN vol. 4, no. 70 (P-12)(552) 23 May 1980 & JP-A-55 036 873 ( DAINIPPON INSATSU K.K. ) 14 March 1980
  • [A] PATENT ABSTRACTS OF JAPAN vol. 5, no. 17 (P-47)(689) 31 January 1981 & JP-A-55 146 471 ( FUJI XEROX K.K. ) 14 November 1980
  • PATENT ABSTRACTS OF JAPAN vol. 1, no. 165 (E-079)26 December 1977 & JP-A-52 110 636 ( CANON K.K. ) 16 September 1977

Designated contracting state (EPC)

AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

EP 0539974 A1 19930505; CA 2081437 A1 19930502; IL 99930 A0 19920818

DOCDB simple family (application)

EP 92118496 A 19921029; CA 2081437 A 19921026; IL 9993091 A 19911101