FLEXOGRAPHIC PRINTING PLATE ASSEMBLY

Abstract

A printing plate assembly for use in flexographic printing application is provided which includes an integral carrier layer, one or more cushion layers, and one or more photopolymer layers. The photopolymer layer(s) in the integral assembly are provided with relief images using digital imaging photopolymerization, which eliminates the need for a back exposure step and provides a precise relief depth for the plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a printing plate assembly according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a printing plate assembly according to another embodiment of the present invention;

FIG. 3 is a cross-sectional view of a printing plate assembly according to another embodiment of the present invention; and

FIG. 4 is a schematic diagram of a digital imaging device used to produce a relief image on the printing plate assembly.

Claims

1. A printing plate assembly for use in flexographic printing comprising: a carrier layer having first and second major surfaces; at least one cushion layer on at least one of said first and second major surfaces of said carrier layer; and at least one imageable photopolymer layer over said carrier layer; said carrier layer, at least one cushion layer, and at least one photopolymer layer forming an integral printing plate assembly.

2. The printing plate assembly of claim 1 wherein said at least one cushion layer is on said first surface of said carrier layer and said at least one photopolymer layer is on said second surface of said carrier layer.

3. The printing plate assembly of claim 1 wherein said at least one cushion layer is overlies said second surface of said carrier layer and said at least one photopolymer layer is on said cushion layer.

4. The printing plate assembly of claim 1 comprising first and second cushion layers and a first photopolymer layer; wherein first cushion layer is on said first surface of said carrier layer; said second cushion layer is on said second surface of said carrier layer, and said first photopolymer layer is on said second cushion layer.

5. The printing plate assembly of claim 1 further including a second photopolymer layer on said at least one imageable photopolymer layer.

6. The printing plate assembly of claim 1 wherein said carrier layer is non-extensible.

7. The printing plate assembly of claim 1 wherein said carrier layer is comprised of vinyl, polyester film, or metal.

8. The printing plate assembly of claim 1 wherein said at least one cushion layer is selected from the group consisting of an open cell foam, a closed cell foam, or a volume displaceable material.

9. The printing plate assembly of claim 1 wherein said at least one cushion layer has a thickness of between about 0.25 mm and 3.25 mm.

10. The printing plate assembly of claim 1 wherein said at least one cushion layer has a thickness of between about 1.0 mm and 1.5 mm.

11. The printing plate assembly of claim 1 wherein said photopolymer layer has been imaged and wherein the relief depth of said printing plate assembly is from about 0.50 mm to about 2.0 mm.

12. The printing plate assembly of claim 1 wherein said at least one photopolymer layer comprises a solid photopolymer selected from a styrenic block copolymer-based material, a urethane-based material, or a rubber-based material.

13. The printing plate assembly of claim 1 wherein said at least one photopolymer layer comprises a liquid photopolymer selected from acrylates, exoxies, urethanes, and unsaturated polyesters.

14. The printing plate assembly of claim 1 wherein said at least one photopolymer comprises a semi-solid photopolymer.

15. A method of making a printing plate assembly for use in flexographic printing comprising: providing a cushion layer;applying a carrier layer on said cushion layer;applying at least one photopolymer layer on said carrier layer to form an integral printing plate assembly; andexposing portions of said at least one photopolymer layer to a source of radiation to cure said photopolymer and form a relief image; andremoving unexposed portions of said photopolymer layer.

16. The method of claim 15 wherein said radiation source is a digital light imaging system.

17. The method of claim 15 including applying a tie coating to said carrier layer prior to applying said photopolymer layer.

18. The method of claim 15 wherein said photopolymer layer comprises a liquid photopolymer.

19. The method of claim 15 wherein said photopolymer layer comprises a solid photopolymer.

20. The method of claim 15 wherein said photopolymer layer comprises a semi-solid photopolymer.

21. The method of claim 15 including exposing said photopolymer layer to radiation at a wavelength of about 365 nm.

22. The method of claim 15 wherein said photopolymer layer has a thickness of between about 1.0 and about 1.5 mm.

23. The method of claim 15 including applying a second photopolymer layer over said at least one photopolymer layer.

24. A method of making a printing plate assembly for use in flexographic printing comprising: providing a first cushion layer;applying a carrier layer on said cushion layer;applying a second cushion layer on said carrier layer;applying a first photopolymer layer on said second cushion layer to form an integral printing plate assembly;exposing portions of said first photopolymer layer to radiation to form a relief image.

25. The method of claim 24 wherein said radiation source is a digital light imaging system.

26. The method of claim 24 including applying a second photopolymer layer on said first photopolymer layer.

27. The method of claim 24 including applying a tie coating to said carrier layer prior to applying said first photopolymer layer.

28. A method of making a printing plate assembly for use in flexographic printing comprising: providing a carrier layer;applying a cushion layer on said carrier layer;applying a photopolymer layer on said cushion layer to form an integral printing assembly; andexposing portions of said photopolymer layer to a source of radiation to form a relief image; andremoving unexposed portions of said photopolymer layer.