Laminate

Abstract

A multilayer body which is obtained by stacking a slip sheet and a planographic printing original plate having an image recording layer that contains an infrared absorbent, a polymerizable compound and a polymerization initiator, wherein the air resistance of the slip sheet is 55 seconds or more. Alternatively, a multilayer body which is obtained by stacking a slip sheet and a planographic printing original plate having an image recording layer that contains an infrared absorbent, a polymerizable compound and a polymerization initiator, wherein: the planographic printing original plate and the slip sheet are superposed upon each other such that the image recording layer-side surface of the planographic printing original plate is in contact with the slip sheet; and the color difference ∆E of the image recording layer between before and after storage for three days in a dark room at 25°C and 55% RH is less than 3.0.

Claims

1. A lithographic printing plate master having an image recording layer containing an infrared absorbent, a polymerizable compound, and a polymerization initiator is laminated with a sheet of paper. The image recording layer side of the lithographic printing plate is placed in contact with the laminate, and the color difference ΔE of the image recording layer before and after storage in a darkroom at 25°C and 55% RH for three days is less than 3.

0. Laminated structure.

2. The laminate according to claim 1, wherein the air permeability resistance of the interleaving paper is 55 seconds or more.

3. The laminate according to claim 1, wherein the image recording layer further comprises an acid colorant.

4. The laminate according to claim 3, wherein the acid colorant comprises a leuco dye.

5. The laminate according to claim 1, wherein the polymerization initiator comprises an electron-donating polymerization initiator.

6. The laminate according to claim 5, wherein the electron-donating polymerization initiator comprises a borate compound.

7. The laminate according to claim 1, wherein the HOMO value of the infrared absorber is -5.30 eV or less.

8. The laminate according to claim 5, wherein the HOMO-HOMO value of the infrared absorber minus the HOMO of the electron-donating polymerization initiator is 0.60 eV or less.

9. The laminate according to claim 1, wherein the lithographic printing plate further comprises a support.

10. Brightness L of the surface on the image recording layer side of the support ＊ The laminate according to claim 9, wherein the value of is 85 or less.

11. The laminate according to claim 1, wherein the pH of the interleaving paper is less than 5.

12. The basis weight of the aforementioned laminated paper is 51 g / m². ２ The laminate according to claim 1, wherein the above is true.

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