Substrate improvements for thermally imageable composition and methods of preparation

• US 6,692,890 B2
• Filed: 04/04/2001
• Issued: 02/17/2004
• Est. Priority Date: 04/04/2001
• Status: Expired due to Fees

• Current Assignee: Eastman Kodak Company
• Original Assignee: Kodak Polychrome Graphics Company Limited (Eastman Kodak Company)
• Inventors: Saraiya, Shashikant, Zhong, Xing-Fu, Pappas, S. Peter, Huang, Jen-Chi
• Primary Examiner(s): Baxter, Janet
• Assistant Examiner(s): Walke, Amanda C.
• Application Number:
  US09/826,315
• Publication Number:
  US 20020172888A1
• Time in Patent Office: 1,049 Days
• Field of Search: 430/270.1, 430/302, 430/303, 205/214
• US Class Current: 430/270.1
• CPC Class Codes: B41C 1/1025 using materials comprising a polymeric matrix containing a polymeric particulate material, e.g. hydrophobic heat coalescing particles
• CPC Class Codes: B41C 2201/04 Intermediate layers
• CPC Class Codes: B41C 2210/04 Negative working, i.e. the non-exposed (non-imaged) areas are removed
• CPC Class Codes: B41C 2210/06 Developable by an alkaline solution
• CPC Class Codes: B41C 2210/10 Developable by an acidic solution
• 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: B41C 2210/262 Phenolic condensation polymers, e.g. novolacs, resols
• CPC Class Codes: B41N 3/03 Chemical or electrical pretreatment
• CPC Class Codes: B41N 3/038 Treatment with a chromium compound, a silicon compound, a phophorus compound or a compound of a metal of group IVB; Hydrophilic coatings obtained by hydrolysis of organometallic compounds

Abstract

The present invention includes a radiation-imageable element for lithographic printing having a hydrophilic anodized aluminum base with a surface having pores and a image-forming layer having polymer particles coated on the aluminum base. The ratio of the average pore diameter to the average particle diameter is from 0.4:1 to 10:1. The present invention further includes a method of producing the imaged element. The method includes the steps of imagewise exposing the radiation-imageable element to radiation to produce exposed and unexposed regions and contacting the imagewise exposed radiation-imageable element and a developer to remove the exposed or the unexposed regions.

Claims

1. A radiation-imageable element for lithographic printing comprising:

a hydrophilic anodized aluminum base having a surface comprising pores characterized by an average pore diameter; and

coated thereon

an image-forming layer comprising polymer particles characterized by an average particle diameter, the ratio of said average pore diameter to said average particle diameter being from 0.4;

1 to 10;

1.

2. The radiation-imageable element of claim 1, wherein said average pore diameter to said average particle diameter ratio is from about 0.5:

1 to about 5;

1.

3. The radiation-imageable element of claim 1, wherein said pores have an average pore diameter from about 10 to about 100 nm.

4. The radiation-imageable element of claim 1, wherein said average pore diameter is from about 10 to about 75 nm.

5. The radiation-imageable element of claim 1, wherein said polymer particles have an average particle diameter from about 1 to about 250 nm.

6. The radiation-imageable element of claim 1, wherein said polymer particles have an average particle diameter from about 10 to about 200 nm.

7. The radiation-imageable element of claim 1, wherein said polymer particles comprise a thermoplastic or thermoset polymer.

8. The radiation-imageable element of claim 1, wherein said image-forming layer further comprises a pigment.

9. The radiation-imageable element of claim 1, wherein said polymer particles comprise a graft polymer having a hydrophobic polymer backbone and a plurality of pendant groups represented by the formula:

10. The radiation-imageable element of claim 1, wherein said polymer particles comprise a homopolymer or a copolymer formed from polymerization of one or more monomers selected from the group consisting of:

acrylic acid, methacrylic acid, acrylamide, methacrylamide, ester of acrylic acid, ester of methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, acrylamide, methacrylamide, N-hydroxyethyl acrylamide, N-hydroxyethyl methacrylamide, styrene, p-hydroxystyrene, α

-methylstyrene, p-methylstyrene, vinyl acetate, methyl vinyl ether, ethyl vinyl ether, hydroxyethyl vinyl ether, vinylphosphonic acid, vinyl chloride, vinylidene chloride, acrylonitrile, N-vinyl pyrrolidone and N-vinyl carbazole.

11. The radiation-imageable element of claim 1, wherein said polymer particles comprise latex particles, phenol-formaldehyde resin, a cresol-formaldehyde resin, melamine-formaldehyde resin, a polyurethane resin and a combination thereof.

12. The radiation-imageable element of claim 1, wherein said polymer particles have a coagulation temperature of at least 40°

C.

13. The radiation-imageable element of claim 12, wherein said coagulation temperature is at least 60°

C.

14. The radiation-imageable element of claim 1, further comprising a photoconverter.

15. The radiation-imageable element of claim 14, wherein said photoconverter is a dye or pigment.

16. The radiation-imageable element of claim 14, wherein said photoconverter is selected from the group consisting of:

an infrared absorbing dye, carbon black, a metal boride, a metal carbide, a metal nitride, a metal carbonitride, bronze-structured oxide and a conductive polymer particle.

17. The radiation-imageable element of claim 1, wherein said hydrophilic anodized aluminum base is an oxide base which comprises oxides and one or both of phosphates and sulfates of aluminum.

18. The radiation-imageable element of claim 17, wherein said oxide base is present in a coverage of greater than 100 milligrams per square meter of said hydrophilic anodized aluminum base.

19. The radiation-imageable element of claim 18, wherein said oxide base is present in a coverage of greater than 500 milligrams per square meter of said hydrophilic anodized aluminum base.

20. The radiation-imageable element of claim 1, further comprising an overlying layer.

21. The radiation-imageable element of claim 1, wherein the ratio of said average pore diameter to said avenge particle diameter is from about 0.95:

1 to about 2.5;

1.

22. The radiation-imageable element of claim 1, wherein said average pore diameter is from about 10 to about 40 nm.

23. The radiation-imageable element of claim 1, wherein said polymer particles have an average particle diameter from about 15 to about 60 nm.

24. The radiation-imageable element of claim 1, and further comprising an interlayer.

25. The radiation-imageable element of claim 24, wherein the interlayer comprises silicate, polyvinyl phosphoric acid, or polyacrylic acid.

26. A radiation-imageable element for lithographic printing comprising:

a hydrophilic anodized aluminum base having a surface comprising pores having an average pore diameter from about 10 to about 100 nm; and

coated thereon

an image-forming layer comprising polymer particles having an average particle diameter from about 1 to about 250 nm;

the ratio of said average pore diameter to said average particle diameter being from about 0.5;

1 to about 5;

1.

27. The radiation-imageable element of claim 26, wherein said average pore diameter is from about 10 to about 75 nm.

28. The radiation-imageable element of claim 26, wherein said polymer particles have an average particle diameter from about 10 to about 200 nm.

29. The radiation-imageable element of claim 26, wherein said polymer particles comprise a thermoplastic or thermoset polymer.

30. The radiation-imageable element of claim 26, wherein said image-forming layer further comprises a pigment.

31. The radiation-imageable element of claim 26, wherein said polymer particles comprise a graft polymer having a hydrophobic polymer backbone and a plurality of pendant groups represented by the formula:

32. The radiation-imageable element of claim 26, wherein said polymer particles comprise a homopolymer or a copolymer formed from polymerization of one or more monomers selected from the group consisting of:

acrylic acid, methacrylic acid, acrylamide, methacrylamide, ester of acrylic acid, ester of methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, acrylamide, methacrylamide, N-hydroxyethyl acrylamide, N-hydroxyethyl methacrylamide, styrene, p-hydroxystyrene, α

-methylstyrene, p-methylstyrene, vinyl acetate, methyl vinyl ether, ethyl vinyl ether, hydroxyethyl vinyl ether, vinylphosphonic acid, vinyl chloride, vinylidene chloride, acrylonitrile, N-vinyl pyrrolidone and N-vinyl carbazole.

33. The radiation-imageable element of claim 26, wherein said polymer particles comprise latex particles, phenol-formaldehyde resin, a cresol-formaldehyde resin, melamine-formaldehyde resin, a polyurethane resin and a combination thereof.

34. The radiation-imageable element of claim 26, wherein the ratio of said average pore diameter to said average particle diameter being from about 0.95:

1 to about 2.5;

1.

35. The radiation-imageable element of claim 26, wherein said average pore diameter is from about 10 to about 40 nm.

36. The radiation-imageable element of claim 26, wherein said polymer particles have an average particle diameter from about 15 to about 60 nm.

37. The radiation-imageable element of claim 26, and further comprising an interlayer.

38. The radiation-imageable element of claim 37, wherein the interlayer comprises silicate, polyvinyl phosphonic acid, or polyacrylic acid.

39. The radiation-imageable element of claim 26, wherein said hydrophilic anodized aluminum base is an oxide base which comprises oxides and one or both of phosphates and sulfates of aluminum.

40. The radiation-imageable element of claim 39 wherein said oxide base is present in a coverage of greater than 100 milligrams per square meter of said hydrophilic anodized aluminum base.

41. The radiation-imageable element of claim 39, wherein said oxide base is present in a coverage of greater than 500 milligrams per square meter of said hydrophilic anodized aluminum base.

42. A method of producing an imaged element for lithographic printing comprising the steps of:

providing a hydrophilic anodized aluminum base having a surface comprising pores characterized by an average pore diameter;

coating thereon an image-forming layer comprising polymer particles characterized by an average particle diameter, the ratio of said average pore diameter to said average particle diameter being from 0.4;

1 to 10;

1; and

imagewise exposing said image-forming layer to radiation to produce exposed and unexposed regions.

43. The method of claim 42, wherein said radiation is thermal radiation.

44. The method of claim 43, wherein said step of exposing said image-forming layer to thermal radiation is carried out using an infrared laser.

45. The method of claim 42, further comprising postbaking said imaged element.

46. An imaged element prepared by the method of claim 42.

47. The method of claim 42, wherein the step of providing the anodized aluminum base comprises anodizing an aluminum base in phosphoric acid.

48. The method of claim 42, wherein the step of providing the anodized aluminum base comprises anodizing an aluminum base in sulfuric acid.

49. The method of claim 42, wherein the step of providing the anodized aluminum base comprises etching the anodized aluminum base to increase the average pore diameter.

50. The method of claim 42, and further including the step of forming an interlayer on the anodized aluminum base.

51. A method of producing an imaged element having complementary ink receiving and ink rejecting regions, said method comprising the steps of:

providing a radiation-imageable element for lithographic printing comprising;

a hydrophilic anodized aluminum base having a surface comprising pores; and

coated thereon, a image-forming layer comprising polymer particles, the ratio of said average pore diameter to said average particle diameter being from about 0.4;

1 to about 10;

1;

imagewise exposing said image-forming layer to radiation to produce exposed and unexposed regions; and

contacting said imagewise exposed image-forming layer and a developer to selectively remove said exposed or said unexposed regions.

52. The method of claim 51, wherein said contacting selectively removes said unexposed regions.

53. An imaged element prepared by the method of claim 51.