Printing plate precursor, printing plate precursor laminate, method for making printing plate, and printing method

1. A method for making a printing plate, comprising:

providing a printing plate precursor comprising:

an aluminum support,

an image recording layer which is provided at a printing surface side of the aluminum support and includes a polymer compound having a particle shape, and

an optional layer which is provided at the printing surface side,

wherein the printing plate precursor contains particles in the image recording layer or the optional layer,

the modulus of elasticity of the particles is 0.7 GPa or more,

in a case where the Bekk smoothness of an outermost layer surface at the printing surface side is denoted by A second, the following expression (1) is satisfied,

the polymer compound is thermoplastic polymer particles or a microgel, and

the thermoplastic polymer particles include styrene and/or acrylonitrile as a constitutional unit:

A≤ 1,000  (1);

image-exposing the printing plate precursor; and

supplying at least one of printing ink or dampening water to remove an unexposed area of the image recording layer on a printing machine and make the printing plate.

2. The method for making a printing plate according to claim 1 ,

wherein the Bekk smoothness A second of the outermost layer surface at the printing surface side satisfies the following expression (2),

A≤ 300  (2).

3. The method for making a printing plate according to claim 1 ,

wherein, in a case where the Bekk smoothness of the outermost layer surface at the printing surface side is denoted by A second and the Bekk smoothness of an outermost layer surface at the side opposite to the printing surface side is denoted by B second, the following expressions (1) and (3) are satisfied,

A≤ 1,000  (1)

1/ A+ 1/ B≥ 0.002  (3).

4. The method for making a printing plate according to claim 1 ,

wherein the arithmetic average height Sa of the outermost layer surface at the printing surface side is in a range of 0.3 μm to 20 μm.

5. The method for making a printing plate according to claim 1 ,

wherein the arithmetic average height Sa of an outermost layer surface at a side opposite to the printing surface side is in a range of 0.1 μm to 20 μm.

6. The method for making a printing plate according to claim 1 ,

wherein the total value of the arithmetic average height Sa of the outermost layer surface at the printing surface side and the arithmetic average height Sa of an outermost layer surface at a side opposite to the printing surface side is more than 0.3 μm and 20 μm or less.

7. The method for making a printing plate according to claim 1 ,

wherein the image recording layer of the printing plate precursor includes an infrared absorbent, a polymerization initiator, and a polymerizable compound.

8. The method for making a printing plate according to claim 1 ,

wherein the image recording layer of the printing plate precursor contains the particles,

the average particle diameter of the particles is in a range of 0.5 μm to 20 μm, and

the in-plane density of the particles is 10,000 particle/mm 2 or less.

9. The method for making a printing plate according to claim 1 ,

wherein a protective layer is the optional layer provided at the printing surface side.

10. The method for making a printing plate according to claim 9 ,

wherein the protective layer contains the particles,

the average particle diameter of the particles is in a range of 0.5 μm to 20 μm, and

the in-plane density of the particles is 10,000 particle/mm 2 or less.

11. The method for making a printing plate according to claim 9 ,

wherein the thickness of the protective layer is less than 0.2 μm.

12. The method for making a printing plate according to claim 1 ,

wherein a non-photosensitive resin layer is the optional layer provided at the printing surface side.

13. The method for making a printing plate according to claim 12 ,

wherein the non-photosensitive resin layer contains the particles, the average particle diameter of the particles is in a range of 0.5 μm to 20 μm, and the in-plane density of the particles is 10,000 particle/mm 2 or less.

14. The method for making a printing plate according to claim 12 ,

wherein a protective layer is further provided at the printing surface side.

15. The method for making a printing plate according to claim 14 ,

wherein the protective layer includes a water-soluble polymer.