QUANTUM DOT-BASED LUMINESCENT MARKING MATERIAL

• US 20090045360A1
• Filed: 08/13/2007
• Published: 02/19/2009
• Est. Priority Date: 08/13/2007
• Status: Abandoned Application

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: IFTIME, Gabriel, WOSNICK, Jordan H., VANBESIEN, Daryl W.
• Application Number:
  US11/837,585
• Publication Number:
  US 20090045360A1
• Time in Patent Office: Days
• US Class Current: 250/586
• CPC Class Codes: B41M 3/144 using fluorescent, luminescent or iridescent effects
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G03G 21/046 by discriminating a special original, e.g. a bank note
• CPC Class Codes: G03G 2215/00299 Confidential, e.g. secret documents
• CPC Class Codes: G03G 2215/00932 Security copies

Abstract

A luminescent marking material includes a luminescent material, which includes quantum dots, and a vehicle for delivering the luminescent material to an object. A method of embedding information on a substrate includes assigning information to luminescent material, which includes quantum dots, forming luminescent marking material by combining luminescent material and marking material, and creating an image on a substrate with the luminescent marking material. A system that embeds and recovers information on a substrate includes an image forming device containing such a luminescent marking material for forming an image on the a substrate and a document reading device including a radiation emitting unit, which emits radiation that causes the luminescent marking material to illuminate, and a reader that detects the data on the substrate while the luminescent marking material is illuminated.

Claims

1. A luminescent marking material comprising:

at least one luminescent material; and

at least one vehicle that delivers the at least one luminescent material to an object,

wherein the at least one luminescent material comprises quantum dots.

2. The luminescent marking material of claim 1, wherein the at least one luminescent material is two or more luminescent materials, wherein emitted or reflected light wavelengths are created by varying the type, number, and concentration of the luminescent materials in the luminescent marking material, and the light wavelength emitted or reflected by each of the two or more luminescent materials is at least machine differentiable from the light wavelength emitted or reflected by the other luminescent materials of the two or more luminescent materials.

3. The luminescent marking material of claim 1, wherein the average size of the quantum dots is from about 2 to about 50 nm.

4. The luminescent marking material of claim 1, wherein the concentration of the quantum dots in the luminescent marking material is from about 0.01 to about 10%.

5. The luminescent marking material of claim 1, wherein the vehicle that delivers the quantum dots to an object comprises material suitable for use in ink jet or bubble jet printing.

6. The luminescent marking material of claim 1, wherein the vehicle that delivers the quantum dots to an object comprises toner suitable for use in electrophotographic imaging.

7. The luminescent marking material of claim 6, wherein the toner is prepared by either conventional or chemical means.

8. The luminescent marking material of claim 6, wherein toner comprises quantum dots imbedded in the toner or contained on the surface of the toner.

9. The luminescent marking material of claim 1, wherein the at least one vehicle for delivering the at least one luminescent material to an object comprises at least one colorant.

10. The luminescent marking material of claim 9, wherein the percentage of the colorant in the vehicle for delivering the at least one luminescent material to an object is from about 1 to about 75% by weight.

11. The luminescent marking material of claim 9, wherein the at least one vehicle for delivering the luminescent material to an object is from 1 to 4 vehicles for delivering the luminescent material to an object, wherein the 1 to 4 vehicles for delivering the luminescent material to an object comprise:

cyan, magenta, yellow, and black toners or inks or a combination thereof; and

at least one luminescent material.

12. The luminescent marking material of claim 1, wherein the vehicle that delivers the at least one luminescent material to an object comprises no colorant.

14. The method according to claim 12, wherein the at least one luminescent material is two or more luminescent materials, and emitted or reflected light wavelengths are created by varying the type, number, and concentration of the luminescent materials in the luminescent marking materials, and the light wavelength emitted or reflected by each of the two or more luminescent materials is at least machine differentiable from the light wavelength emitted or reflected by the other luminescent materials of the two or more luminescent materials.

15. The method according to claim 12, wherein the at least one luminescent marking material comprises colorant.

16. The method according to claim 15, wherein the at least one luminescent marking material is from 1 to 4 luminescent marking materials, wherein the 1 to 4 marking materials comprise cyan, magenta, yellow, and black toners or inks or a combination thereof

17. The method according to claim 16, wherein emitted or reflected light wavelength combinations are created by varying the type, number, and concentration of luminescent materials in each of the 1 to 4 luminescent marking materials.

18. The method according to claim 12, wherein the at least one luminescent marking material comprises no colorant.

13. A method of embedding information on a substrate comprising:

assigning information to at least one luminescent material;

forming at least one luminescent marking material by combining the at least one luminescent material and at least one marking material; and

creating an image on a substrate with the at least one luminescent marking material,

wherein the at least one luminescent material comprises quantum dots.

19. A system for embedding and recovering readable information on a substrate, comprising:

an image forming device containing at least one luminescent marking material, wherein the image forming device receives data representative of the readable information, and forms an image corresponding to the data with the at least one luminescent marking material on an image receiving substrate; and

a document reading device including a radiation emitting unit that emits radiation effecting luminescence of then at least one luminescent marking material, and a reader that detects the data in the image on the image receiving substrate while the at least one luminescent marking material is illuminated,

wherein the at least one luminescent marking material comprises at least one luminescent material; and

at least one vehicle that delivers the at least one luminescent material to an object, wherein the at least one luminescent material comprises quantum dots.

20. The method according to claim 19, wherein the machine capable of detecting and differentiating light wavelengths emitted or reflected by the at least one luminescent material is a spectrometer, spectrophotometer, spectrofluorimeter, or a combination thereof.