Infrared-ray photosensitive planographic printing plate precursor
The infrared-ray photosensitive planographic printing plate precursor of the present invention comprises a support, a recording layer provided on one side of the support, and a back coating layer provided on a side opposite to a side having the recording layer of the support, and the recording layer contains (a) a long chain alkyl group-containing polymer containing a vinyl monomer having a carboxyl group at a composition ratio within a range from 20 to 99 mol %, and (b) an infrared absorbing agent, and can form an image by infrared-ray irradiation. According to this planographic printing plate precursor, even when the precursor is packaged and transported without using a protective paper (interleaving paper) between plate materials, a recording layer is hardly scratched.
1 . An infrared-ray photosensitive planographic printing plate precursor, comprising:
a support,
a recording layer provided on one side of the support, and
a back coating layer provided on a side opposite to a side having the recording layer of the support,
wherein the recording layer contains (a) a long chain alkyl group-containing polymer constituted from a vinyl monomer having a carboxyl group at a composition ratio within a range from 20 to 99 mol %, and (b) an infrared absorbing agent, and can form an image by infrared-ray irradiation.
2 . The infrared-ray photosensitive planographic printing plate precursor of claim 1 , wherein the back coating layer is a back coating layer (A) containing at least one kind of resin selected from the group consisting of a polymerized saturated polyester resin, a phenoxy resin, a polyvinyl acetal resin, and a vinylidene chloride copolymer resin, or a back coating layer (B) containing the following (i) to (iii):
(i) a metal oxide obtained by hydrolyzing and polycondensing an organic metal compound or an inorganic metal compound,
(ii) a colloidal silica sol, and
(iii) an organic polymer compound.
3 . The infrared-ray photosensitive planographic printing plate precursor of claim 1 , wherein (a) the long chain alkyl group-containing polymer is a copolymer represented by the following formula (I).
In the formula (I), X and X′ each represents, independently, a single bond or a bivalent connecting group, m represents an integer of 20<m<99, n represents an integer of 6 to 40, and a bond indicated by a dotted line means that there is a methyl group or hydrogen atom at its terminal.
4 . The infrared-ray photosensitive planographic printing plate precursor of claim 3 , wherein in the formula (I), 30<m<90, and 12<n<30.
5 . The infrared-ray photosensitive planographic printing plate precursor of claim 4 , wherein in the formula (I), 45<m<80, and 14<n<20.
6 . The infrared-ray photosensitive planographic printing plate precursor of claim 1 , wherein (a) the long chain alkyl group-containing polymer is an acryl-based copolymer represented by the following formula (II):
In the formula (II), X and X′ each represents, independently, a single bond or a bivalent connecting group, m represents an integer of 20<m<99, n represents an integer of 6 to 40, and a bond indicated by a dotted line means that there is a methyl group or hydrogen atom at its terminal.
7 . The infrared-ray photosensitive planographic printing plate precursor of claim 6 , wherein in the formula (II), 30<m<90, and 12<n<30.
8 . The infrared-ray photosensitive planographic printing plate precursor of claim 7 , wherein in the formula (II), 45<m<80, and 14<n<20.
9 . The infrared-ray photosensitive planographic printing plate precursor of claim 1 , wherein (a) the long chain alkyl group-containing polymer is an acryl-based copolymer represented by the following formula (III):
In the formula (III), X and X′ each represents, independently, a single bond or a bivalent connecting group, m represents an integer of 20<m<99, n represents an integer of 6 to 40, and a bond indicated by a dotted line means that there is a methyl group or hydrogen atom at its terminal.
10 . The infrared-ray photosensitive planographic printing plate precursor of claim 9 , wherein in the formula (III), 30<m<90, and 12<n<30.
11 . The infrared-ray photosensitive planographic printing plate precursor of claim 10 , wherein in the formula (III), 45<m<80, and 14<n<20.
12 . The infrared-ray photosensitive planographic printing plate precursor of claim 1 , wherein (a) the long chain alkyl group-containing polymer is an acryl-based polymer represented by the following formula (IV) or the formula (V):
In the formula (IV) and the formula (V), X and X′ each represents, independently, a single bond or a bivalent connecting group, m represents an integer of 20<m<99, n represents an integer of 6 to 40, and a bond indicated by a dotted line means that there is a methyl group or hydrogen atom at its terminal.
13 . The infrared-ray photosensitive plangraphic printing plate precursor of claim 12 , wherein in the formula (IV) and the formula (V), 30<m<90, and 12<n<30.
14 . The infrared-ray photosensitive plangraphic printing plate precursor of claim 13 , wherein in the formula (IV) and the formula (V), 45<m<80, and 14<n<20.
15 . The infrared-ray photosensitive plangraphic printing plate precursor of claim 1 , wherein surface roughness (Ra) of the back coating layer is 0.25 or lower.
16 . The infrared-ray photosensitive planographic printing plate precursor of claim 2 , wherein a glass transition temperature of the resin used in the back coating layer (A) is 60° C. or higher.
17 . An infrared-ray photosensitive planographic printing plate precursor, comprising:
a support,
a recording layer provided on one side of the support, and
a back coating layer provided on a side opposite to a side having the recording layer of the support,
wherein, the recording layer contains (a) a long chain alkyl group-containing polymer containing a vinyl monomer having a carboxyl group at a composition ratio within a range from 20 to 99 mol %, and (b) an infrared absorbing agent, and can form an image by infrared-ray irradiation, and
the back coating layer is a back coating layer (A) containing at least one kind of resin selected from the group consisting of a saturated polymerized polyester resin, a phenoxy resin, a polyvinyl acetal resin, and a vinylidene chloride copolymer resin.
18 . The infrared-ray photosensitive planographic printing plate precursor of claim 17 , wherein a glass transition temperature of the resin used in the back coating layer (A) is 60° C. or higher.
19 . An infrared-ray photosensitive planographic printing plate precursor, comprising:
a support,
a recording layer provided on one side of the support, and
a back coating layer provided on a side opposite to a side having the recording layer of the support,
wherein the recording layer contains (a) a long chain alkyl group-containing polymer containing a vinyl monomer having a carboxyl group at a composition ratio within a range from 20 to 99 mol %, and (b) an infrared absorbing agent, and can form an image by infrared-ray irradiation, and
the back coating layer is a back coating layer (B) containing the following (i) to (iii):
(i) a metal oxide obtained by hydrolyzing and polycondensing an organic metal compound or an inorganic metal compound,
(ii) a colloidal silica sol, and
(iii) an organic polymer compound.