Identification matter

• US 4,500,116 A
• Filed: 07/14/1980
• Issued: 02/19/1985
• Est. Priority Date: 01/18/1978
• Status: Expired due to Term

• Current Assignee: Consignia Plc (International Distributions Services plc)
• Original Assignee: Post Office Limited (International Distributions Services plc)
• Inventors: Walker, Aubrey D., Ferro, Berkeley M.
• Primary Examiner(s): Bell, Paul A.
• Application Number:
  US06/168,151
• Time in Patent Office: 1,681 Days
• Field of Search: 428/916, 428/913, 430/10, 235/491, 283/7, 283/8, 283/74, 283/75, 283/89, 283/92, 283/94, 283/109, 283/904, 40/2 R
• US Class Current: 283/92
• CPC Class Codes: B42D 2033/04 Transparent material
• CPC Class Codes: B42D 2033/20 Coloured material; Pigments or inks
• CPC Class Codes: B42D 2033/28 Paper or card board
• CPC Class Codes: B42D 2033/30 Plastic material
• CPC Class Codes: B42D 2035/06 Picture of the user
• CPC Class Codes: B42D 2035/08 Alphanumerical data
• CPC Class Codes: B42D 25/00 Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof printing processes to produce identification or security features B41M3/14
• CPC Class Codes: B42D 25/309 Photographs
• CPC Class Codes: B42D 25/324 Reliefs
• CPC Class Codes: B42D 25/387 absorbing or reflecting ultraviolet light
• CPC Class Codes: B42D 25/415 using chemicals B42D25/445 takes precedence
• CPC Class Codes: B42D 25/425 by deformation, e.g. embossing
• CPC Class Codes: Y10S 283/904 Credit card
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10S 428/916 Fraud or tamper detecting

Abstract

A credential, such as a passport or an identification card, is provided, for example by impregnation or coating, with a phosphorescent composition which includes at least two phosphorescence activators which exhibit different emission characteristics both with respect to wavelength and lifetime so that, when the composition is irradiated, the initial afterglow changes color, for example from green to blue.

Claims

1. An article for establishing personal identity, comprising a substrate carrying identification markings, said substrate having thereon or therein a phosphorescent material comprising a rigid matrix in which there are dispersed two or more organic phosphorescense activators which are unresponsive to visible light and which during and after irradiation with ultraviolet light emit visible phosphorescense, said matrix being transparent to radiation at the excitation and emission frequencies of said phosphorescense activators, said emissions of said phosphorescense activators differing from one another with respect to both wavelengths and lifetime, whereby the total emission of said phosphorescent material after cessation of said irradiation changes from an initial colour representing the combined emissions of said activators to a final colour representing the emission of that activator having the longest phosphorescence lifetime.

2. An article as claimed in claim 1, wherein the phosphorescent material contains two phosphorescence activators.

3. An article as claimed in claim 2, wherein the phosphorescent material contains, as activators, carbazole sulphonic acid or a salt thereof and p-aminobenzophenone.

4. An article as claimed in claim 1, wherein the phosphorescent material comprises a cross-linked condensation resin prepared by a condensation reaction in the presence of the phosphorescence activators.

5. An article as claimed in claim 4, wherein the cross-linked resin is a condensation resin selected from the group consisting of urea formaldehyde resins and melamine-formaldehyde resins.

6. An article as claimed in claim 1, wherein the substrate comprises:

(a) a core of paper, board or plastics material, said core bearing said identification markings and

(b) an outer covering comprising at least one layer of transparent plastics material, said outer covering having at least one inner surface adjacent said core, said phosphorescent material being present in the form of printed matter on at least one of said core and said inner surface.

7. An article as claimed in claim 1, wherein the substrate comprises:

(a) a core of paper or board, said core bearing said identification markings, and

(b) an outer covering comprising at least one layer of transparent plastics material, said phosphorescent material being coated onto said core or distributed througout said core.