Electrophotographic varnish composition

Patent metadata

Field	Value
Publication number	US-10139742-B2
Application number	US-201515547744-A
Country	US
Kind code	B2
Filing date	Feb 11, 2015
Priority date	Feb 11, 2015
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

An electrophotographic varnish composition that comprises, in a liquid carrier, a polymeric resin; an epoxy-based cross-linking agent, a mono-epoxy diluent and a metal catalyst and/or a photo-initiator. Also described herein is a method for making such electrophotographic varnish composition.

First claim

The invention claimed is:

1. An electrophotographic varnish composition comprising, in a liquid carrier,
a. an epoxy-based cross-linking agent;
b. a mono-epoxy diluent;
c. a polymeric resin;
d. and a metal catalyst and/or a photo-initiator.

2. The electrophotographic varnish composition according to claim 1 wherein the mono-epoxy diluent is a linear mono-epoxy diluent, a branched mono-epoxy diluent or a mixture of linear and branched mono-epoxy diluents.

3. The electrophotographic varnish composition according to claim 1 wherein the mono-epoxy diluent is selected from the group consisting of 2-ethylhexyl glycidyl ether, glycidyl hexadecyl ether and dodecyl/tetradecyl glycidyl ether.

4. The electrophotographic varnish composition according to claim 1 wherein the mono-epoxy diluent is present in an amount representing from about 0.1 wt % to about 10 wt % of the total weight of the electrophotographic varnish composition.

5. The electrophotographic varnish composition according to claim 1 wherein the ratio epoxy-based cross-linking agent/mono-epoxy diluent is between 1/1 and 1/0.8.

6. The electrophotographic varnish composition according to claim 1 wherein the epoxy-based cross-linking agent is present in an amount representing from about 0.1 wt % to about 10 wt % of the total weight of the electrophotographic varnish composition.

7. The electrophotographic varnish composition according to claim 1 wherein the epoxy-based cross-linking agent has a molecular weight of 5000 Daltons or less.

8. The electrophotographic varnish composition according to claim 1 wherein the epoxy-based cross-linking agent is of the formula (X)-(Y[Z-F] m ) n wherein, in each (Y[Z-F] m ) n , Y, Z and F are each independently selected, such that F is an epoxide of the formula —CH(O)CR 2 H, wherein R 1 is selected from H and alkyl; Z is alkylene; Y is selected from (i) a single bond, —O—, —C(═O)—O—, —O—C(═O)— and m is 1 or (ii) Y is —NH 2-m , wherein m is 1 or 2; n is at least 1, and X is an organic group.

9. The electrophotographic varnish composition according to claim 1 wherein the epoxy-based cross-linking agent is selected from the group consisting of 1,2,7,8-diepoxy octane; trimethylolpropane triglycidyl ether, resorcinol diglycidyl ether; N,N-diglycidyl-4-glycidyloxyaniline; 4,4′-Methylenebis(N,N-diglycidylaniline); tris(4-hydroxyphenyl)methane triglycidyl ether; diglycidyl 1,2-cyclohexanedicarboxylate; 1,4-cyclohexanedimethanol diglycidyl ether; tris(2,3-epoxypropyl) isocyanurate; neopentyl glycol diglycidyl ether;
bisphenol-A diglycidyl ether; bisphenol-A propoxylate diglycidyl ether; 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate; poly[(o-cresyl glycidyl ether)-co-formaldehyde]; poly(ethylene-co-glycidyl methacrylate); poly(ethylene-co-methyl acrylate-co-glycidyl methacrylate); poly(bisphenol A-co-epichlorohydrin) glycidyl end-capped; poly(ethylene glycol) diglycidyl ether and poly(propylene glycol) diglycidyl ether.

10. The electrophotographic varnish composition according to claim 1 wherein a metal catalyst is present in an amount representing less than 5 wt % of the total weight of the electrophotographic varnish composition and is a chromium complex or a zinc complex.

11. The electrophotographic varnish composition according to claim 1 wherein a photo-initiator is present in an amount representing from about 0.01 to about 10 wt % of the total weight of the electrophotographic varnish composition and is a cationic photo-initiator.

12. The electrophotographic varnish composition according to claim 1 wherein the polymeric resin comprises two different polymers having acidic side groups that are co-polymers of ethylene and an ethylenically unsaturated acid of either acrylic acid or methacrylic acid or ionomers thereof.

13. The electrophotographic varnish composition according to claim 1 that further comprises a charge director.

14. An article comprising a substrate printed with an electrophotographic ink composition and with an electrophotographic varnish composition comprising in a liquid carrier, an epoxy-based cross-linking agent; a mono-epoxy diluent; a polymeric resin; and a metal catalyst and/or a photo-initiator.

15. A method of manufacturing an electrophotographic varnish composition comprising mixing, in a carrier liquid, a polymeric resin, an epoxy-based cross-linking agent, a mono-epoxy diluent, and a metal catalyst and/or a photo-initiator to form the electrophotographic composition.

Assignees

• Hp Indigo Bv

Inventors

• Azzam Tony
• Mor Ilanit
• Farran Samer
• Nesher Guy
• Biadglin Getahun
• Cohen Haim
• Kowal-Blau Yael
• Teishev Albert
• Carmel-Barnea Nurit

Classifications

• G03G9/133

  Graft-or block polymers · CPC title

• G03G9/132

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09D123/0869

  Acids or derivatives thereof · CPC title

• G03G9/131

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G8/00 Primary

  Layers covering the final reproduction, e.g. for protecting, for writing thereon · CPC title