Organic photoconductor drum having an overcoat containing nano metal oxide particles and method to make the same

Patent metadata

Field	Value
Publication number	US-10678153-B2
Application number	US-201916398842-A
Country	US
Kind code	B2
Filing date	Apr 30, 2019
Priority date	Nov 3, 2017
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.

First claim

What is claimed is:

1. A method of preparing an organic photoconductor drum comprising:
providing an electrically conductive substrate;
preparing a charge generation layer dispersion:
coating the charge generation layer dispersion over the electrically conductive substrate to form a charge generation layer;
preparing a charge transport layer dispersion:

coating the charge transport layer dispersion over the charge generation layer to form a charge transport layer;
preparing an overcoat layer formulation including:
about 70 percent to about 95 percent by weight of a urethane acrylate resin having at least six radical polymerizable functional groups;
about 5 percent to about 30 percent by weight of indium tin oxide particles sized less than 200 nm; and
an organic solvent;

coating the overcoat layer formulation over the charge transport layer; and
curing the overcoat layer formulation to form a photoconductor having an overcoat layer over the charge transport layer and the charge generation layers, wherein the overcoat layer does not include charge transport materials.

2. The method of claim 1 , wherein the urethane acrylate resin having at least six radical polymerizable functional groups is a hexa-functional aromatic urethane acrylate resin having the following structure:

3. The method of claim 1 , wherein the urethane resin having at least six radical polymerizable functional groups is a hexa-functional aliphatic urethane acrylate resin having the following structure:

4. The method of claim 1 , wherein the overcoat layer is cured by an electron beam.

5. The method of claim 4 , wherein the cured overcoat layer has a thickness of about 0.1 μm to about 10 μm.

6. The method of claim 1 , wherein the overcoat layer formulation further includes a monomer or oligomer having at most five radical polymerizable functional groups.

7. The method of claim 1 , wherein the overcoat layer formulation further includes a coating aid additive at an amount equal to or less than about 10 percent by weight of the curable composition.

8. The method of claim 7 , wherein the amount of the coating aid additive is about 0.1 to about 5 percent by weight of the curable composition.

9. The method of claim 7 , wherein the coating aid additive is a surfactant.

Assignees

• Lexmark Int Inc

Inventors

• Luo Weimei
• Bellino Mark Thomas

Classifications

• G03G5/147

  Cover layers · CPC title

• G03G5/0592 Primary

  Macromolecular compounds characterised by their structure or by their chemical properties, e.g. block polymers, reticulated polymers, molecular weight, acidity · CPC title

• G03G5/14713

  Macromolecular material · CPC title

• G03G5/102

  consisting of or comprising metals · CPC title

• G03G5/06

  characterised by the photoconductive material being organic · CPC title