Electrophotographic composition

Patent metadata

Field	Value
Publication number	US-10474052-B2
Application number	US-201515745035-A
Country	US
Kind code	B2
Filing date	Oct 9, 2015
Priority date	Oct 9, 2015
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

The present disclosure relates to an electrophotographic composition that comprises a polymer resin mixture and a liquid carrier. The polymer resin mixture comprises (i) an olefin polymer A having acid and/or ester side groups and a melt index of 22 to 100 g/10 min; and (ii) an olefin polymer B having a melt index of 1 to 20 g/10 min. The olefin polymer B forms 1 to 50 weight % of the polymer resin mixture.

First claim

The invention claimed is:

1. A liquid electrophotographic varnish composition consisting of:
a polymer resin mixture consisting of:
(i) an olefin polymer A having acid and/or ester side groups and a melt index of 22 to 100 g/10 min, wherein the olefin polymer A forms 50 to 99 weight % of the polymer resin mixture or a blend of olefin polymers A; and
(ii) an olefin polymer B, wherein the olefin polymer B is a terpolymer of a) an olefin, b) an acrylic acid, methacrylic acid, an acrylate, or methacrylate, and c) a polar monomer selected from the group consisting of glycidyl methacrylate and maleic anhydride, wherein the olefin polymer B has a melt index of 1 to 20 g/10 min, and wherein the olefin polymer B forms 1 to 50 weight % of the polymer resin mixture; and

a liquid carrier.

2. The composition as claimed in claim 1 , wherein the olefin polymer A has a melting point of greater than 78 degrees C. and the olefin polymer B has a melting point of less than 75 degrees C.

3. The composition as claimed in claim 1 , wherein the olefin polymer B forms 5 to 25 weight % of the polymer resin mixture.

4. The composition as claimed in claim 1 , wherein the olefin polymer B has a melting point of 60 to 70 degrees C.

5. The composition as claimed in claim 1 , wherein the olefin polymer B is soluble in the liquid carrier.

6. The composition as claimed in claim 1 , wherein the olefin polymer B swells by at least 70% when soaked in the liquid carrier at a temperature of 45 degrees for 96 hours.

7. The composition as claimed in claim 1 , wherein the olefin polymer B has a melt index of 1 to 10 g/10 min.

8. The composition as claimed in claim 1 , wherein the terpolymer includes ethylene as the olefin, methyl acrylate as the acrylate, and glycidyl methacrylate as the polar monomer.

9. The composition as claimed in claim 1 , wherein the olefin polymer A is a copolymer of ethylene and acrylic acid or methacrylic acid.

10. The composition as claimed in claim 1 , wherein the olefin polymer A has a melt index of 25 g/10 min to 70 g/10 min.

11. The composition as claimed in claim 1 , wherein the blend of olefin polymers A consists of a first polymer having acid and/or ester side groups and a melt index of 22 to 30 g/10 min and a second polymer having acid and/or ester side groups and a melt index of 50 to 80 g/10 min.

12. The composition as claimed in claim 1 , wherein the olefin polymer A has an olefin content of 78 to 90 weight % and the olefin polymer B has an olefin content of 60 to 70 weight %.

13. A method of electrophotographically printing an image on a substrate, said method comprising:
electrophotographically printing an electrophotographic ink composition onto the substrate to form an image; and
electrophotographically printing the liquid electrophotographic varnish composition according to claim 1 over the image.

14. The composition as claimed in claim 1 , wherein the terpolymer includes ethylene as the olefin, the methacrylic acid, and glycidyl methacrylate as the polar monomer.

15. The composition as claimed in claim 1 , wherein the terpolymer includes ethylene as the olefin, ethyl acrylate as the acrylate, and maleic anhydride as the polar monomer.

16. The composition as claimed in claim 1 , wherein the terpolymer includes:
from 60 to 78 weight % of the olefin;
from about 20 to 35 weight % of the acrylic acid, the methacrylic acid, the acrylate, or the methacrylate; and
from about 0.1 to about 10 weight % of the polar monomer.

17. The composition as claimed in claim 1 wherein:
wherein the blend of olefin polymers A consists of a first polymer and a second polymer;
the first polymer is a copolymer of ethylene and methacrylic acid; and
the second polymer is copolymer of ethylene and acrylic acid.

18. A method of forming a liquid electrophotographic varnish composition, said method comprising:
melting (i) an olefin polymer A having acid and/or ester side groups and a melt index of 22 to 100 g/10 min; and (ii) an olefin polymer B to form a polymer resin mixture, wherein the olefin polymer B is a terpolymer of a) an olefin, b) an acrylic acid, methacrylic acid, an acrylate, or methacrylate, and c) a polar monomer selected from the group consisting of glycidyl methacrylate and maleic anhydride, wherein the olefin polymer B has a melt index of 1 to 20 g/10 min, and wherein the olefin polymer A forms 50 to 99 weight % of the polymer resin mixture and the olefin polymer B forms 1 to 50 weight % of the polymer resin mixture;
allowing the polymer resin mixture to cool;
grinding the polymer resin mixture to form particles consisting of the olefin polymer A and the olefin polymer B; and
dispersing the particles in a liquid carrier to form the liquid electrophotographic varnish composition consisting of the particles and the liquid carrier.

Assignees

• Hp Indigo Bv

Inventors

• Nesher Guy
• Biadglin Getahun
• Cohen Haim
• Azzam Tony
• Farran Samer
• Mor Ilanit
• Parvin Noam
• Teishev Albert

Classifications

• G03G8/00

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

• G03G9/081

  by mixing the toner components in a liquefied state; melt kneading; reactive mixing · CPC title

• G03G9/131 Primary

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

• G03G9/133

  Graft-or block polymers · CPC title

• G03G9/13

  characterised by polymer components · CPC title