Method and compositions for authenticating a product or document

• US 5,786,509 A
• Filed: 09/27/1996
• Issued: 07/28/1998
• Est. Priority Date: 05/31/1995
• Status: Expired due to Fees

• Current Assignee: Nocopi Technologies, Inc.
• Original Assignee: Nocopi Technologies, Inc.
• Inventors: Stevenson, Kevin Bruce, Belding, Blake Quenten, Stovold, Terry William, Silknitter, JoAnn
• Primary Examiner(s): Gerstl, Robert
• Application Number:
  US08/722,329
• Time in Patent Office: 669 Days
• Field of Search: 568/716, 106/21 A, 106/21 R, 564/223
• US Class Current: 564/223
• CPC Class Codes: B41M 3/142 using chemical colour-formers or chemical reactions, e.g. leuco-dye/acid, photochromes
• CPC Class Codes: B41M 5/124 using pressure to make a masked colour visible, e.g. to make a coloured support visible, to create an opaque or transparent pattern, or to form colour by uniting colour-forming components
• CPC Class Codes: G03G 21/04 Preventing copies being made of an original
• CPC Class Codes: G03G 21/043 by using an original which is not reproducible or only reproducible with a different appearence, e.g. originals with a photochromic layer or a colour background

Abstract

A method and compositions for authenticating a document or article comprises applying a mixture of a carrier, a leuco dye and an activator to a surface of a document or article, wherein the leuco dye and activator react in response to a rubbing force applied to the surface to change color and wherein the activator is at least one selected from the group consisting of amidophenol, anilides with hydroxyl groups and benzoamides with hydroxyl groups and authenticating the document or article by applying a rubbing force to the surface to effect a color change.

Claims

1. A composition for use as an activator for a leucodye, wherein the activator is wet micronized and comprises at least one selected from the group consisting of amidophenol, anilides with hydroxyl groups and benzoamides with hydroxyl groups.

2. The composition according to claim 1, wherein the activator has a melting point above 115°

C.

3. The composition according to claim 1, wherein the activator comprises ##STR6## wherein R₁ is a phenolic derivative or --C₆ H₄ OH;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

4. The composition according to claim 1, wherein the activator comprises ##STR7## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

5. The composition according to claim 1, wherein the activator comprises ##STR8## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is a branched or unbranched alkyl group or an aryl group;

R₃ is H, a branched or unbranched alkyl group or an aryl group; and

R₄ is H, a branched or unbranched alkyl group or an aryl group.

6. The composition according to claim 1, wherein the activator comprises ##STR9## where R=H, alkyl or aryl derivatives.

7. The composition according to claim 1, wherein the activator comprises ##STR10## where R=hydroxyalkyl or hydroxyaryl derivatives.

8. A compound for use as an activator for a leucodye, wherein the activator is wet micronized and consists essentially of at least one selected from the group consisting of amidophenol, anilides with hydroxyl groups and benzoamides with hydroxyl groups.

9. The compound according to claim 8, wherein the activator has a melting point above 115°

C.

10. The compound according to claim 8, wherein the activator comprises ##STR11## wherein R₁ is a phenolic derivative or --C₆ H₄ OH;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

11. The compound according to claim 8, wherein the activator comprises ##STR12## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

12. The compound according to claim 8, wherein the activator comprises ##STR13## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is a branched or unbranched alkyl group or an aryl group;

R₃ is H, a branched or unbranched alkyl group or an aryl group; and

R₄ is H, a branched or unbranched alkyl group or an aryl group.

13. The compound according to claim 8, wherein the activator comprises ##STR14## where R=H, alkyl or aryl derivatives.

14. The compound according to claim 8, wherein the activator comprises ##STR15## where R=hydroxyalkyl or hydroxyaryl derivatives.

15. A composition for use as an activator for a leucodye, wherein the activator has a melting point above 115°

and comprises at least one selected from the group consisting of amidophenol, anilides with hydroxyl groups and benzoamides with hydroxyl groups.

16. The composition according to claim 15, wherein the activator comprises ##STR16## wherein R₁ is a phenolic derivative or --C₆ H₄ OH;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

17. The composition according to claim 15, wherein the activator comprises ##STR17## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is H, a branched or unbranched alkyl group or an aryl group; and

R₃ is H, a branched or unbranched alkyl group or an aryl group.

18. The composition according to claim 15, wherein the activator comprises ##STR18## wherein R₁ is a o-, m-, or p-phenolic group;

R₂ is a branched or unbranched alkyl group or an aryl group;

R₃ is H, a branched or unbranched alkyl group or an aryl group; and

R₄ is H, a branched or unbranched alkyl group or an aryl group.

19. The composition according to claim 15, wherein the activator comprises ##STR19## where R=H, alkyl or aryl derivatives.

20. The composition according to claim 15, wherein the activator comprises ##STR20## where R=hydroxyalkyl or hydroxyaryl derivatives.