Polymeric gravure printing form and process for preparing the same with curable composition having a multifunctional urethane

Patent metadata

Field	Value
Publication number	US-10166754-B2
Application number	US-201815899464-A
Country	US
Kind code	B2
Filing date	Feb 20, 2018
Priority date	Apr 2, 2015
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

The invention pertains to a printing form and a process for preparing a polymeric printing form from a curable composition that includes a multifunctional urethane in a specified reactive group equivalent weight range, and an initiator. The process includes coating the curable composition onto a supporting substrate, such as a print cylinder, to form a layer, curing the layer with heat or by exposure to actinic radiation, and engraving the resulting cured layer to form at least one printing cell in the cured layer. The process prepares novel polymeric printing forms, particularly novel polymeric gravure printing forms, having a cured polymer-based composition layer that is engravable, resistant to solvent inks, and capable of printing gravure-quality images. The present invention shortens the time to prepare gravure printing cylinders and removes the need for and disposal of toxic heavy metals such as copper and chrome associated with conventional gravure print cylinder preparation.

First claim

What is claimed is:

1. A printing form comprising a supporting substrate and a print surface adjacent to the supporting substrate, wherein the print surface is a cured layer of a curable composition comprising a multifunctional urethane, and an initiator, and optionally a reactive diluent, wherein the composition is characterized by a reactive group equivalent weight of the multifunctional urethane and the optional reactive diluent that is between 250 and 450 g/equivalent, and wherein the initiator is a photoinitiator, and is not an organic epoxide.

2. The printing form of claim 1 wherein the multifunctional urethane has two or more ethylenically unsaturated groups, and the curable composition further comprises one or more reactive diluents having two or more ethylenically unsaturated groups, and the reactive group equivalent weight of the curable composition is the weighted average of the reactive group equivalent weights of the one or more reactive diluents and the multifunctional urethane, and is between 250 and 450 g/equivalent.

3. The printing form of claim 1 wherein the multifunctional urethane is a multifunctional acrylated urethane having two or more (meth)acrylate groups, and the reactive group equivalent weight is an acrylate equivalent weight that is between 250 and 450 g/equivalent.

4. The printing form of claim 1 wherein the curable composition further comprises one or more resin modifiers independently selected from the reactive diluent, monofunctional diluents, monomers, auxiliary resin modifying compounds, or combinations thereof.

5. The printing form of claim 1 wherein the multifunctional urethane comprises one or more multifunctional acrylated urethanes having two or more (meth)acrylate groups, the initiator is a photoinitiator; and the optional reactive diluent comprises one or more reactive diluents having two or more (meth)acrylate groups, and the reactive group equivalent weight of the composition is an acrylate equivalent weight that is the weighted average of the acrylate equivalent weights of the one or more reactive diluents and the multifunctional acrylated urethane, and is between 250 and 450 g/equivalent.

6. The printing form of claim 1 wherein the multifunctional urethane comprises one or more multifunctional acrylated urethanes having two or more (meth)acrylate groups, at least one reactive diluent having two or more (meth)acrylate groups, and an auxiliary resin modifying compound having two or more (meth)acrylate groups, and wherein the reactive group equivalent weight of the curable composition is an acrylate equivalent weight that is the weighted average of the acrylate equivalent weights of the one or more multifunctional acrylated urethanes, the at least one reactive diluent, and the auxiliary resin modifying compound, and is between 250 and 450 g/equivalent.

7. The printing form of claim 1 wherein the curable composition further comprises at least one reactive diluent that has a viscosity of less than or equal to 300 cp and is selected from the group of difunctional (meth)acrylate monomers, difunctional (meth)acrylate oligomers, trifunctional (meth)acrylate monomers, trifunctional (meth)acrylate oligomers, and combinations thereof.

8. A printing form precursor comprising:
a supporting substrate; and
a layer of a curable composition adjacent to the supporting substrate, wherein the curable composition comprises a multifunctional urethane, and an initiator, and optionally a reactive diluent, wherein the curable composition has reactive group equivalent weight between 250 and 450 g/equivalent, based upon the multifunctional urethane and the optional reactive diluent, and wherein the initiator is a photoinitiator, and is not an organic epoxide.

9. The printing form precursor of claim 8 wherein the multifunctional urethane has two or more ethylenically unsaturated groups, and the curable composition further comprises one or more reactive diluents having two or more ethylenically unsaturated groups, and the reactive group equivalent weight of the curable composition is the weighted average of the reactive group equivalent weights of the one or more reactive diluents and the multifunctional urethane, and is between 250 and 450 g/equivalent.

10. The printing form precursor of claim 8 wherein the multifunctional urethane is a multifunctional acrylated urethane having two or more (meth)acrylate groups, and the reactive group equivalent weight is an acrylate equivalent weight that is between 250 and 450 g/equivalent.

11. The printing form precursor of claim 8 wherein the curable composition further comprises one or more resin modifiers independently selected from the reactive diluent, monofunctional diluents, monomers, auxiliary resin modifying compounds, or combinations thereof.

12. The printing form precursor of claim 8 wherein the multifunctional urethane comprises one or more multifunctional acrylated urethanes having two or more (meth)acrylate groups, the initiator is a photoinitiator; and the optional reactive diluent comprises one or more reactive diluents having two or more (meth)acrylate groups, and the reactive group equivalent weight of the composition is an acrylate equivalent weight that is the weighted average of the acrylate equivalent weights of the one or more reactive diluents and the multifunctional acrylated urethane, and is between 250 and 450 g/equivalent.

13. The printing form precursor of claim 8 wherein the multifunctional urethane comprises one or more multifunctional acrylated urethanes having two or more (meth)acrylate groups, at least one reactive diluent having two or more (meth)acrylate groups, and an auxiliary resin modifying compound having two or more (meth)acrylate groups, and wherein the reactive group equivalent weight of the curable composition is an acrylate equivalent weight that is the weighted average of the acrylate equivalent weights of the one or more multifunctional acrylated urethanes, the at least one reactive diluent, and the auxiliary resin modifying compound, and is between 250 and 450 g/equivalent.

14. The printing form precursor of claim 8 wherein the curable composition further comprises at least one reactive diluent that has a viscosity of less than or equal to 300 cp and is selected from the group of difunctional (meth)acrylate monomers, difunctional (meth)acrylate oligomers, trifunctional (meth)acrylate monomers, trifunctional (meth)acrylate oligomers, and combinations thereof.

15. A curable multifunctional urethane composition for use as a printing surface in a printing form comprising:
a) 30 to 95 wt % of at least one multifunctional urethane having two or more reactive groups;
b) 0.1 to 10 wt % of at least one initiator;
c) 0 to 40 wt % of one or more reactive diluents having two or more reactive groups;
d) 0 to 20 wt % of one or more monofunctional diluents;
e) 0 to 20 wt % of one or more monomers;
f) 0 to 35 wt % of one or more auxiliary resin modifying compounds; wherein the total of the reactive diluents, monofunctional diluents, monomers, and auxiliary resin modifying compounds is no more than 40 wt % of the curable composition;
g) 0 to 55 wt % of particulate filler selected from nanoparticles, microparticles, and combinations thereof; and
optionally, up to 10 wt % total of one or more of additives independently selected from adhesion promotors, slip agents, flow and leveling agents, wetting agents, plasticizers, flexibilizing agents, stabilizers, antioxidants, or dispersants;
wherein the wt % is based on the total of the solid components in the curable composition; wherein the curable composition has a reactive group equival

Assignees

• Du Pont

Inventors

• Shuey Steven W
• Lungu Adrian
• Shah Mukesh C
• Figuly Garret D

Classifications

• C08G18/672

  Esters of acrylic or alkyl acrylic acid having only one group containing active hydrogen · CPC title

• C08G18/00

  Polymeric products of isocyanates or isothiocyanates · CPC title

• B41N1/22

  made of other substances · CPC title

• B41N1/12

  non-metallic other than stone {, e.g. printing plates or foils comprising inorganic materials in an organic matrix (B41N1/003, B41N1/006 take precedence)} · CPC title

• B41M1/10

  Intaglio printing {; Gravure printing} · CPC title