Method for producing printed matter

Patent metadata

Field	Value
Publication number	US-10906294-B2
Application number	US-201716094639-A
Country	US
Kind code	B2
Filing date	May 19, 2017
Priority date	May 27, 2016
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

The present invention aims to provide a method of producing a printed matter that shows suppressed scumming in planography. A method of producing a printed matter, the method including the steps of: allowing a dampening water to adhere to a hydrophilic layer of a planographic printing plate having at least the hydrophilic layer and a heat sensitive layer; allowing an ink to adhere to the heat sensitive layer; and transferring the ink adhering to the heat sensitive layer to an object to be printed; wherein the pH (A) of the ink and the pH (B) of the dampening water are both from 1 to 6.5.

First claim

The invention claimed is:

1. A method of producing a printed matter, the method comprising the steps of:
providing a planographic printing plate having disposed thereon a hydrophilic layer and a heat sensitive layer disposed on the hydrophilic layer;
providing dampening water to adhere to the hydrophilic layer;
providing an ink to adhere to the heat sensitive layer; and
transferring the ink adhering to the heat sensitive layer to an object to be printed; wherein
the ink comprises a resin having an acidic group, and a polyfunctional (meth)acrylate having a hydroxyl group; and
the pH (A) of the ink and the pH (B) of the dampening water are both from 1 to 6.5.

2. The method of producing a printed matter according to claim 1 , wherein the pH (A) of the ink and the pH (B) of the dampening water satisfy (A)>(B).

3. The method of producing a printed matter according to claim 1 , wherein the pH (B) of the dampening water is from 3 to 6.

4. The method of producing a printed matter according to claim 1 , wherein the pH (A) of the ink is from 3 to 6.

5. The method of producing a printed matter according to claim 1 , wherein the difference between the pH (A) of the ink and the pH (B) of the dampening water (pH (A)−pH (B)) is from 1 to 2.

6. The method of producing a printed matter according to claim 1 , wherein the step of transferring the adhering ink to the object to be printed is a step of transferring the adhering ink to the object to be printed, directly or through a blanket.

7. The method of producing a printed matter according to claim 1 , comprising a step of irradiating the ink transferred to the object to be printed, with an active energy ray.

8. The method of producing a printed matter according to claim 7 , wherein the active energy ray is an emission line having a wavelength of from 350 to 420 nm emitted from a light emitting diode.

9. The method of producing a printed matter according to claim 1 , comprising a step of washing the printing plate and/or the blanket with wash water after printing.

10. The method of producing a printed matter according to claim 9 , wherein the wash water has a pH of from 8 to 13.

11. The method of producing a printed matter according to claim 1 , wherein the acidic group of the resin having an acidic group has at least one selected from the group consisting of a carboxyl group, a sulfo group, and a phosphate group.

12. The method of producing a printed matter according to claim 1 , wherein the resin having an acidic group has an acid value of from 30 mg KOH/g to 250 mg KOH/g.

13. The method of producing a printed matter according to claim 1 , wherein the resin having an acidic group has an ethylenically unsaturated group.

14. The method of producing a printed matter according to claim 13 , wherein the resin having an acidic group has an iodine value of from 0.5 mol/kg to 3.0 mol/kg.

15. The method of producing a printed matter according to claim 1 , wherein the polyfunctional (meth)acrylate having a hydroxyl group has a hydroxyl value of from 50 mg KOH/g to 200 mg KOH/g.

16. The method of producing a printed matter according to claim 1 , wherein the ink comprises a photopolymerization initiator.

17. The method of producing a printed matter according to claim 1 , wherein the ink comprises a surfactant.

18. The method of producing a printed matter according to claim 17 , wherein the surfactant has an HLB value of from 8 to 18.

19. The method of producing a printed matter according to claim 17 , wherein the content of the surfactant in the ink is from 1% by mass to 10% by mass.

20. The method of producing a printed matter according to claim 1 , wherein the ink comprises the resin having an acidic group in an amount of 5% to 50% by mass, and the polyfunctional (meth)acrylate having a hydroxyl group in an amount of 20% to 70% by mass.

Assignees

• Toray Industries

Inventors

• Tsuji Yuichi
• Inoue Takejiro

Classifications

• B41F35/06

  for offset cylinders · CPC title

• B41F35/02

  for forme cylinders · CPC title

• B41N3/08

  Damping; Neutralising or similar differentiation treatments for lithographic printing formes; {Gumming or finishing solutions, fountain solutions, correction or deletion fluids, or on-press development (treatment of materials containing silver salts G03F7/063; developers per se for processing photosensitive materials G03F7/32)} · CPC title

• C09D11/03

  characterised by features other than the chemical nature of the binder · CPC title

• B41M5/26

  Thermography (B41M5/20, B41M5/24 take precedence); {Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used (B23K takes precedence; thermographic or photothermographic systems using noble metal compounds G03C1/494)} · CPC title