Laser engraving methods and compositions, and articles having laser engraving thereon

• US 20030234286A1
• Filed: 12/20/2002
• Published: 12/25/2003
• Est. Priority Date: 12/24/2001
• Status: Abandoned Application

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Jones, Robert, Labrec, Brian
• Application Number:
  US10/326,886
• Publication Number:
  US 20030234286A1
• Time in Patent Office: Days
• US Class Current: 235/380
• CPC Class Codes: B41M 3/14 Security printing securities B42D25/29
• CPC Class Codes: B41M 5/24 Ablative recording, e.g. by burning marks; Spark recording marking by high energetic means, e.g. by laser otherwise than burning or ablative removal B41M5/26; materials or methods for recording or reproduction by optical means G11B7/00
• CPC Class Codes: B41M 5/267 Marking of plastic artifacts, e.g. with laser
• CPC Class Codes: B41M 7/0027 using protective coatings or layers by lamination or by fusion of the coatings or layers
• CPC Class Codes: B42D 25/41 using electromagnetic radiation B42D25/435 takes precedence
• CPC Class Codes: C08K 3/16 Halogen-containing compounds
• CPC Class Codes: C08K 3/30 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: Y10S 430/146 Laser beam
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

The invention provides a composition having laser engraving properties, comprising a host material and an effective amount of a laser enhancing additive. The laser enhancing additive comprises a first quantity of least one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI), and a second quantity at least one substance selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester. The composition can be engraved with grayscale images by an Nd:Yag laser and can be added to laminates or coatings. The composition can be used during the manufacture of many articles of manufacture, including identification documents.

Claims

1. A composition having laser engraving properties, comprising:

a host material; and

an effective amount of a laser enhancing additive, the laser enhancing additive comprising;

a first quantity of at least one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI); and

a second quantity of at least one substance selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester.

2. The composition as recited in claim 1, wherein the laser enhancing additive is present in an amount from about 0.001 to 100 percent by weight based on the total weight of the composition.

3. The composition as recited in claim 1, wherein host material is substantially transparent and the laser enhancing additive is present in an amount from about 0.001 to 0.1 percent by weight based on the total weight of the composition.

4. The composition as recited in claim 1, wherein the laser enhancing additive is present in an amount that is about 0.06 percent by weight based on the total weight of the composition.

5. The composition as recited in claim 1, wherein the composition comprises a coating.

6. The composition as recited in claim 1, wherein the composition comprises a laminate.

7. The composition as recited claim 1, wherein the composition is laser engraveable to form a grayscale image.

8. An article of manufacture capable of being laser engraved with a grayscale image, comprising:

a core layer having a first surface;

a first layer comprising a first host material, the first host material comprising an effective amount of a first laser enhancing additive comprising at least one of one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI); and

a second layer comprising a second host material, the second layer oriented in relation to the first host material such that a single laser beam can penetrate both at least a portion of the first layer and at least a portion of the second layer, the second host material comprising an effective amount of a second laser enhancing additive, the second laser enhancing additive selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester;

wherein the first and second layers are operably coupled to each other and at least one of the first and second layers is operably coupled to the first surface of the core layer.

10. The article of manufacture as recited in claim 8, wherein the article of manufacture is an identification document.

9. The article of manufacture as recited in claim 9, further comprising a grayscale image laser engraved into at least one of the first and second layers.

11. A method of engraving a material by exposing the material to laser radiation, comprising:

adding to the material an effective amount of a laser enhancing additive, the laser enhancing additive comprising;

at least one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI); and

at least one substance selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester; and

exposing the material to laser radiation in a manner that causes the material to be engraved by the laser radiation.

12. The method recited in claim 12, wherein the effective amount of the laser enhancing additive comprises 0.001% to 100% by weight of the material.

13. The method recited in claim 12, further comprising laser engraving an indicium in grayscale in at least a portion of the material.

14. The method recited in claim 12, further comprising using the laser engraved material in the manufacture of an identification document.

15. An identification document, comprising:

a core layer;

a first layer overlaying at least a portion of the core layer and affixed to the portion of the core layer, the first layer comprising an additive that comprises;

an effective amount of least one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI); and

an effective amount of at least one substance selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester.

16. The identification document of claim 15, wherein the first layer is at least one of a coating and a laminate.

17. The identification document recited in claim 15, wherein the identification document bears a first indicium thereon, the indicium obtained by directing a laser beam through at least a portion of the first layer.

18. The identification document recited in claim 17, wherein the indicium comprises at least one of a gray scale image, photograph, text, tactile text, graphics, information, security pattern, security indicia, and digital watermark.

19. The identification document recited in claim 17 wherein the first indicia comprises variable information.

20. The identification document recited in 15 above, wherein the first layer further comprises:

a first sub layer comprising an effective amount of least one of copper potassium iodide (CuKI₃) or Copper Iodide (CuI); and

a second sub layer comprising an effective amount of at least one substance selected from the group consisting of zinc sulfide (ZnS), barium sulfide (BaS), alkyl sulfonate, and thioester.