Laser-imageable printing members and methods for wet lithographic printing

• US 6,632,584 B1
• Filed: 09/08/2000
• Issued: 10/14/2003
• Est. Priority Date: 10/04/1999
• Status: Expired due to Fees

• Current Assignee: Creo Incorporated (Eastman Kodak Company)
• Original Assignee: Creo Incorporated (Eastman Kodak Company)
• Inventors: Morgan, David A.
• Primary Examiner(s): Baxter, Janet
• Assistant Examiner(s): Lee, Sin J.
• Application Number:
  US09/657,826
• Time in Patent Office: 1,131 Days
• Field of Search: 430/271.1, 430/275.1, 430/278.1, 430/281.1, 430/300, 430/302, 430/945, 101/456, 101/457, 101/458, 101/459
• US Class Current: 430/271.1
• CPC Class Codes: B41C 1/1008 by removal or destruction of lithographic material on the lithographic support, e.g. by laser or spark ablation; by the use of materials rendered soluble or insoluble by heat exposure, e.g. by heat produced from a light to heat transforming system; by on-the-press exposure or on-the-press development, e.g. by the fountain of photolithographic materials
• CPC Class Codes: B41C 2210/04 Negative working, i.e. the non-exposed (non-imaged) areas are removed
• CPC Class Codes: B41C 2210/08 Developable by water or the fountain solution
• CPC Class Codes: B41C 2210/22 characterised by organic non-macromolecular additives, e.g. dyes, UV-absorbers, plasticisers
• CPC Class Codes: B41C 2210/24 characterised by a macromolecular compound or binder obtained by reactions involving carbon-to-carbon unsaturated bonds, e.g. acrylics, vinyl polymers
• CPC Class Codes: Y10S 430/146 Laser beam

Abstract

A thermosensitive composition consisting of a mixture of polyacrylic acid, a salt of a long chain fatty acid such as silver behenate, an infra-red absorbent and modifiers such as additional polymers and fillers. Both the water solubility and affinity to water and oil changed when composition is heated.

Claims

1. A negative working wet printing member imageable by laser radiation, said member comprising:

(a) a hydrophilic surface layer comprising one or more polymers and an absorber, said absorber being characterized by absorption of said laser radiation and said surface layer being characterized by non-ablative absorption of said laser radiation;

(b) a substrate underlying said surface layer;

wherein said surface layer comprises metal salts of organic acids, and poly(meth)acryloyl polymer binder.

2. The member of claim 1 wherein said metal of said metal salts comprises silver or copper.

3. The member of claim 2 wherein said polymer comprises polyacrylic acid.

4. The member of claim 2 wherein said metal salts comprises a salt of a sulfamide.

5. The member of claim 4 wherein said polymer comprises polyacrylic acid.

6. The member of claim 2 wherein said metal salts comprises a salt of a sulfadiazine.

7. The member of claim 6 wherein said polymer comprises polyacrylic acid.

8. A laser imaged lithographic printing master derived from the member of claim 1 comprising a substrate and a surface layer said substrate comprises a dimensionally stable substrate coated with a layer of the surface layer, the surface layer also containing an absorber for absorbing radiation of said laser.

9. The member of claim 1 wherein the metal salt is selected from the group consisting of metal salts of sulfamide, sulfanylamide, acetosulfamine, sulfapyridine, sulfaguanidine, sulfamethoxazole, sulfathiazole, sulfadiazine, sulfamerazine, sulfamethazine, sulfaisoxazole, homosulfamine, sulfisomidine, sulfaguanidine, sulfamethizole, sulfapyradine, phthalisosulfathiazole, and succinylsulfathiazole.

10. The member of claim 9 wherein the metal of the metal salt comprises silver or copper.

11. A process for forming a negative working wet printing member imageable by laser radiation, said member comprising:

a hydrophilic surface layer comprising one or more polymers and an absorber, said absorber being characterized by absorption of said laser radiation and said surface layer being characterized by non-ablative absorption of said laser radiation;

a substrate underlying said surface layer;

wherein the surface layer comprises metal salts of organic acids, polymer binder, and an acryloyl composition and the member is addressed by a laser to alter the properties of the surface layer.

12. The process of claim 11 wherein said metal of said metal salts comprises silver or copper.

13. The process of claim 12 wherein the surface layer also contains zinc oxide.

14. The process of claim 13 wherein the metal salt is selected from the group consisting of silver or copper salts of sulfamide, sulfanylamide, acetosulfamine, sulfapyridine, sulfaguanidine, sulfamethoxazole, sulfathiazole, sulfadiazine, sulfamerazine, sulfamethazine, sulfaisoxazole, homosulfamine, sulfisomidine, sulfaguanidine, sulfamethizole, sulfapyradine, phthalisosulfathiazole, and succinylsulfathiazole.

15. The process of claim 14 wherein the acryloyl composition comprises polyacrylic acid.

16. The process of claim 13 wherein the acryloyl composition comprises polyacrylic acid.

17. The process of claim 12 wherein the metal salts comprises a salt of a sulfamide.

18. The process of claim 12 wherein the metal salts comprises a salt of a sulfadiazine.

19. The process of claim 11 wherein the surface layer also contains zinc oxide.

20. A negative working wet printing member imageable by laser radiation, said member comprising:

(d) a hydrophilic surface layer comprising one or more polymers and an absorber, said absorber being characterized by absorption of said laser radiation and said surface layer being characterized by non-ablative absorption of said laser radiation;

(b) a substrate underlying said surface layer;

wherein said surface layer comprises metal salts of organic acids, polymer binder, and an acryloyl compound.

21. The member of claim 20 wherein said metal of said metal salts comprises silver or copper.

22. The member of claim 21 wherein said metal salts comprises a salt of a sulfamide.

23. The member of claim 22 wherein said sulfamide comprises sulfadiazine.

24. The member of claim 21 wherein acryloyl compound comprises polyacrylic acid.

25. The member of claim 20 wherein the acryloyl compound comprises an acid.

26. The member of claim 20 wherein the metal salt is selected from the group consisting of metal salts of sulfamide, sulfanylamide, acetosulfamine, sulfapyridine, sulfaguanidine, sulfamethoxazole, sulfathiazole, sulfadiazine, sulfamerazine, sulfamethazine, sulfaisoxazole, homosulfamine, sulfisomidine, sulfaguanidine, sulfamethizole, sulfapyradine, phthalisosulfathiazole, and succinylsulfathiazole.

27. The member of claim 26 wherein the metal of the metal salt comprises silver or copper.