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Security documents

Assignee: 3M Innovative Properties Co
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Filing: 1993-03-22
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Granted: 1994-11-22
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Expires: 2013-03-22
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Abstract

Abstract A method for making security documents using an electro photographic printer, particularly a photocopier or laser printer, includes the step of exposing the printed image to an accelerator, in liquid or vapour form. Under the influence of the accelerator, a second dye contained in the toner, used in producing the image, migrates into the document, thereby producing a second image in the paper in registration with the printed image. The process is applicable to images created on paper, security paper, and synthetic papers.

Inventors

  • 👤 Joel F. Shaw
  • 👤 Gary A. Van Beek

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:22
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08784; G03G9/08791; B; B41; B41M; B41M3/00; B41M3/14; G03G11/00; G03G13/00; G03G13/01; G03G13/013; G03G13/0137; G03G8/00; G03G9/08775; G03G9/08782; G03G9/08795; G03G9/08797; G03G9/09; G03G9/0902; G03G9/0904; G03G9/0926

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 130 words
A process for printing a security document which comprises: (i) creating an image pattern by means of an electro photographic printer; (ii) applying to the generated image, within the electro photographic printer, at least one particulate toner, which toner includes a first dye, and at least a minor proportion of a second dye; (iii) transferring and bonding the at least one particulate toner to the surface of the document to provide a document including an electro photographically printed image; and (iv) exposing at least a part of the electro photographically printed image on the document to an accelerator in liquid or vapour form to cause a major proportion of the second dye to migrate into the document, in registration with at least a part of the electro photographically printed image.
Claim 2
Dependent Claim 130 words
A process for printing a security document which comprises: (i) creating an image pattern by means of an electro photographic printer; (ii) applying to the generated image, within the electro photographic printer, at least one particulate toner, which toner includes a first dye, and at least a minor proportion of a second dye; (iii) transferring and bonding the at least one particulate toner to the surface of the document to provide a document including an electro photographically printed image; and (iv) exposing at least a part of the electro photographically printed image on the document to an accelerator in liquid or vapour form to cause a major proportion of the second dye to migrate into the document, in registration with at least a part of the electro photographically printed image.
Claim 3
Dependent Claim 22 words
A process according to claim 1 wherein the second dye forming the migrated image is a different colour to the printed image.
Claim 4
Dependent Claim 19 words
A process according to claim 1 wherein only a part of the printed image is exposed to the accelerator.
Claim 5
Dependent Claim 17 words
A process according to claim 1 wherein all of the printed image is exposed to the accelerator.
Claim 6
Dependent Claim 20 words
A process according to claim 1 wherein the printed image is black, and the migrated image is a different colour.
Claim 7
Dependent Claim 30 words
A process according to claim 1 wherein the printed image is polychromatic, and the second dye comprises a minor proportion of the coloured dye in the at least one toner.
Claim 8
Dependent Claim 13 words
A process according to claim 1 wherein the accelerator is an organic solvent.
Claim 9
Dependent Claim 23 words
A process according to claim 7 wherein the organic solvent is chosen from the group consisting of isopropanol, ethanol, methanol, acetone and methylethylketone.
Claim 10
Dependent Claim 13 words
A process according to claim 1 wherein the document is printed onto paper.
Claim 11
Dependent Claim 14 words
A process according to claim 9 wherein the document is printed onto security paper.
Claim 12
Dependent Claim 14 words
A process according to claim 1 wherein the document is printed onto synthetic paper.
Claim 13
Dependent Claim 25 words
A process according to claim 11 wherein the synthetic paper comprises a microporous, single layer, highly filled, polyolefin plastic film, wherein the filler is silica.
Claim 14
Dependent Claim 15 words
A process according to claim 1 wherein the electro photographic printer is a laser printer.
Claim 15
Dependent Claim 14 words
A process according to claim 13 wherein the electro photographic printer is a photocopier.

References Cited (Backward Citations)

US4680458A Cited
US4579754A Cited
US4903254A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-11-21 1998-05-23 1998-11-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-11-21 2002-05-23 2002-11-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-11-21 2006-05-23 2006-11-22 $7700.00 Window Closed / Lapsed

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