Lithographic printing plate precursor comprising graphite oxide

Patent metadata

Field	Value
Publication number	US-10632734-B2
Application number	US-201615746515-A
Country	US
Kind code	B2
Filing date	Jul 18, 2016
Priority date	Jul 23, 2015
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

A lithographic printing plate precursor includes, on a support, a layer of graphite oxide capable of switching from a hydrophilic state into a hydrophobic state upon exposure to heat and/or light.

First claim

The invention claimed is:

1. A heat-sensitive lithographic printing plate precursor comprising:
a support; and
a coating on the support and including an imaging layer including graphite oxide that converts from a hydrophilic state to a hydrophobic state upon exposure to heat and/or light; wherein
the imaging layer has a thickness up to 10 μm.

2. The printing plate precursor according to claim 1 , wherein the graphite oxide is present in the imaging layer in an amount from 0.05 mg/m 2 to 10 g/m 2 .

3. The printing plate precursor according to claim 1 , wherein the support includes aluminum.

4. The printing plate precursor according to claim 3 , wherein the aluminum is grained and anodized.

5. The printing plate precursor according to claim 1 , wherein the coating further includes an IR-dye.

6. The printing plate precursor according to claim 5 , wherein the IR-dye is water-soluble.

7. The printing plate precursor according to claim 5 , wherein the IR-dye includes a cyanine dye.

8. The printing plate precursor according to claim 7 , wherein the cyanine dye has a chemical structural according to one of the following formulas:

wherein
A represents hydrogen, a halogen, —NR 1 —CO—R 2 , or —NR 1 SO 2 R 3 ;
R 1 represents hydrogen or an optionally substituted alkyl or (hetero)aryl group, SO 3 − , COOR 4 , or forms a ring structure together with R 2 or R 3 ;
R 2 and R 3 independently represent an optionally substituted alkyl or (hetero)aryl group, OR 5 , NR 6 R 7 , or CF 3 ;
R 4 and R 5 independently represent an optionally substituted alkyl or (hetero)aryl group;
R 6 and R 7 independently represent hydrogen, an optionally substituted alkyl or (hetero)aryl group, or form a ring structure with each other;
R y and R y′ independently represent hydrogen, an optionally substituted alkyl group, or represent necessary atoms to form an optionally substituted ring structure; and
* represent linking positions to a remaining portion of the IR-dye.

9. The printing plate precursor according to claim 8 , wherein A represents:
—NR 8 —CO—OC(CH 3 ) 3 ;
—NR 8 —SO 2 —CF 3 ; or
—NR 8 —SO 2 —C 6 H 4 —R 9 ; and
R 8 and R 9 independently represent hydrogen or an alkyl group.

10. The printing plate precursor according to claim 9 , wherein the IR-dye has a chemical structure:

wherein
T and T′ independently represent one or more substituents or an annulated ring;
Z and Z′ independently represent —O—, —S—, —CR 10 R 11 C—, or —CH═CH— in which R 10 and R 11 independently represent an alkyl or aryl group;
R z and R z′ independently represent an optionally substituted alkyl group; and
X − renders the IR-dye neutral.

11. The printing plate precursor according to claim 5 , wherein the IR-dye is present in the coating in an amount between 5 and 50% by weight.

12. A method for making a lithographic printing plate precursor comprising the steps of:
providing a support;
applying on the support a coating as defined in claim 1 ; and
drying the coating.

13. A method for making a lithographic printing plate comprising the steps of:
providing the printing plate precursor according to claim 1 ; and
image-wise exposing the printing plate precursor to heat and/or infrared light.

14. The method according to claim 13 , wherein the image-wise exposing step converts exposed areas of the printing plate precursor from a hydrophilic state to a hydrophobic state.

15. A method of lithographic printing comprising the steps of:
providing the printing plate precursor according to claim 1 ;
image-wise exposing the printing plate precursor to heat and/or infrared light to convert exposed areas of the printing plate precursor from a hydrophilic state to a hydrophobic state at exposed areas; and
mounting the exposed printing plate precursor on a printing press and starting printing by applying ink and/or dampening liquid to the exposed printing plate precursor.

Assignees

• Agfa Nv
• Agfa Gevaert

Inventors

• Desmet Tim

Classifications

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• G03F7/20

  Exposure; Apparatus therefor (photographic printing apparatus for making copies G03B27/00) · CPC title

• B41N1/14

  Lithographic printing foils {(B41N1/003, B41N3/03 take precedence; compositions of the image-forming layer B41C1/10)} · CPC title

• B41C1/1041 Primary

  by modification of the lithographic properties without removal or addition of material, e.g. by the mere generation of a lithographic pattern · CPC title

• B41M1/06

  Lithographic printing · CPC title