A lithographic printing plate precursor comprising a support and a photosensitive layer, wherein the photosensitive layer comprises a photosensitive resin composition containing (A) a sensitizing dye absorbing light of from 350 to 450 nm, (B) a polymerization initiator, (C) a polymerizable compound and (D) a binder polymer, and (D) the binder polymer is an acrylic resin containing a hydrophilic group and a crosslinkable group and having an acid value of 0.3 meq/g or less.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a structure of an automatic development processor.
Claims
1. A lithographic printing plate precursor comprising: a support; and a photosensitive layer,
the photosensitive layer comprising:a sensitizing dye absorbing light of from 350 to 450 nm;a polymerization initiator;a polymerizable compound; anda binder polymer,wherein the binder polymer is an acrylic resin containing a hydrophilic group and a crosslinkable group and having an acid value of 0.3 meq/g or less.
2. A lithographic printing plate precursor comprising: a support; and a photosensitive layer,
the photosensitive layer comprising:a sensitizing dye absorbing light of from 350 to 450 nm;a polymerization initiator;a polymerizable compound; anda binder polymer,wherein the binder polymer is an acrylic resin having an SP value of from 19.0 to 21.5 (MPa)1/2 and an acid value of 0.3 meq/g or less.
3. The lithographic printing plate precursor as claimed in claim 2, wherein the acrylic resin contains a hydrophilic group and a crosslinkable group.
4. The lithographic printing plate precursor as claimed in claim 1, wherein the acrylic resin contains a polymerization unit containing a hydrophilic group and a crosslinkable group.
5. The lithographic printing plate precursor as claimed in claim 4, wherein the crosslinkable group is an ethylenically unsaturated bonding group.
6. The lithographic printing plate precursor as claimed in claim 5, wherein the ethylenically unsaturated bonding group is an allyl group or a methacryloyl group.
7. The lithographic printing plate precursor as claimed in claim 1, which further comprises a protective layer, so that the support, the photosensitive layer and the protective layer are provided in this order.
8. The lithographic printing plate precursor as claimed in claim 1, wherein a part or all of components of the photosensitive layer is encapsulated in a microcapsule.
9. The lithographic printing plate precursor as claimed in claim 1, wherein the polymerization initiator is a hexaarylbiimidazole compound.
10. The lithographic printing plate precursor as claimed in claim 1, wherein the photosensitive layer further comprises a chain transfer agent.
11. The lithographic printing plate precursor as claimed in claim 10, wherein the chain transfer agent is a thiol compound represented by the following formula (I):
12. The lithographic printing plate precursor as claimed in claim 1, wherein a total amount of the polymerizable compound and the binder polymer is 80% by weight or less based on a total component of the photosensitive layer.
13. The lithographic printing plate precursor as claimed in claims 1, which further comprises an undercoat layer between the support and the photosensitive layer, and the undercoat layer contains a polymer compound having s crosslinkable group.
14. A method for preparation of a lithographic printing plate comprising:
imagewise exposing a lithographic printing plate precursor comprising a support and a photosensitive layer containing a sensitizing dye absorbing light of from 350 to 450 nm, a polymerization initiator, a polymerizable compound and a binder polymer of an acrylic resin containing a hydrophilic group and a crosslinkable group and having an acid value of 0.3 meq/g or less with a laser beam of from 350 to 450 nm; andrubbing a surface of the exposed lithographic printing plate precursor with a rubbing member in a presence of a developer having pH of from 2 to 10 in an automatic processor equipped with the rubbing member to remove an unexposed area of the photosensitive layer.
15. A method for preparation of a lithographic printing plate comprising:
imagewise exposing a lithographic printing plate precursor comprising a support and a photosensitive layer containing a sensitizing dye absorbing light of from 350 to 450 nm, a polymerization initiator, a polymerizable compound and a binder polymer of an acrylic resin having an SP value of from 19.0 to 21.5 (MPa)1/2 and an acid value of 0.3 meq/g or less with a laser beam of from 350 to 450 nm; andrubbing a surface of the exposed lithographic printing plate precursor with a rubbing member in a presence of a developer having pH of from 2 to 10 in an automatic processor equipped with the rubbing member to remove an unexposed area of the photosensitive layer.
16. The method as claimed in claim 14, wherein the pH of the developer is from 3 to 8.
17. The method as claimed in claim 14, wherein the rubbing member comprises at least two rotating brush rollers.
18. The method as claimed in claim 14, wherein the exposed lithographic printing plate precursor is subjected to a heat treatment between the exposing and the rubbing.
Patent Application
20070212641
