Light sensitive planographic printing plate material and planographic printing plate manufacturing process

Abstract

Disclosed is a light sensitive planographic printing plate material comprising a support and provided thereon, a light sensitive layer containing a polymeric binder, a polymerizable ethylenically unsaturated compound and a photopolymerization initiator, wherein the polymeric binder is a polymer having a acid value of from 40 to 120 and a glass transition temperature Tg of from 105 to 200 ° C.

Description

Claims

1. A light sensitive planographic printing plate material comprising a support and provided thereon, a light sensitive layer containing a polymeric binder, a polymerizable ethylenically unsaturated compound and a photopolymerization initiator, wherein the polymeric binder is a polymer having an acid value of from 40 to 120 and a glass transition temperature Tg of from 105 to 200° C.

2. The light sensitive planographic printing plate material of claim 1, wherein said polymer has an acid value of from 60 to 110 and a glass transition temperature Tg of from 110 to 180° C.

3. The light sensitive planographic printing plate material of claim 1, wherein said polymer is a copolymer containing two or more kinds of monomer units, the glass transition temperature of a homopolymer consisting of one of the monomer units constituting the copolymer being not less than 105° C.

4. The light sensitive planographic printing plate material of claim 3, wherein the copolymer comprises a (meth)acrylic acid monomer unit in the molecule.

5. The light sensitive planographic printing plate material of claim 1, wherein the polymerizable ethylenically unsaturated compound has both amide bond and a secondary or tertiary amino group in the molecule.

6. The light sensitive planographic printing plate material of claim 1, wherein the photopolymerization initiator is selected from the group consisting of a polyhalogenated compound, a biimidazole compound and an iron arene complex.

7. The light sensitive planographic printing plate material of claim 6, wherein the photopolymerization initiator is a combination of a polyhalogenated compound and an iron arene complex.

8. The light sensitive planographic printing plate material of claim 1, wherein the content of the polymeric binder in the light sensitive layer is from 10 to 90% by weight, based on the total weight of the light sensitive layer, the content of the polymerizable ethylenically unsaturated compound in the light sensitive layer is from 1.0 to 80% by weight, based on the total weight of the light sensitive layer, and the content of the photopolymerization initiator in the light sensitive layer is from 0.1 to 20% by weight, based on the weight of the polymerizable ethylenically unsaturated compound contained in the light sensitive layer.

9. The light sensitive planographic printing plate material of claim 8, wherein the content ratio by weight of the polymerizable ethylenically unsaturated compound to the polymeric binder in the light sensitive layer is from 0.5 to 2.2.

10. The light sensitive planographic printing plate material of claim 1, wherein the light sensitive layer further contains an organic amine.

11. The light sensitive planographic printing plate material of claim 10, wherein the organic amine content of the light sensitive layer is from 0.1 to 20% by weight.

12. The light sensitive planographic printing plate material of claim 10, wherein the organic amine is represented by formula (I),

13. A process for manufacturing a planographic printing plate from the light sensitive planographic printing plate material of claim 1, the process comprising the steps of: (a) imagewise exposing the light sensitive planographic printing plate material;(b) pre-heating the resulting imagewise exposed planographic printing plate material at a temperature of less than Tg of the polymeric binder; and(c) developing the pre-heated planographic printing plate material, whereby a planographic printing plate is obtained.