Photoconductor having an overcoat with tetrafunctional radical polyermizable charge transport molecule and non-radical polymerizable additive

Abstract

An organic photoconductor drum includes a support element, a charge generation layer over the support element, a charge transport layer over the charge generation layer, and an overcoat layer. The overcoat layer includes a curable composition having both a non-radical polymerizable additive and a charge transport molecule containing four radical polymerizable functional groups exemplified as:where R1 and R2 contain a spacer group and a radical polymerizable functional group, R3 and R4 are hydrogen atoms, and R5 and R6 contain a spacer group and a radical polymerizable functional group wherein the spacer group of R1, R2, R5, and R6, is an ethyl group and the radical polymerizable functional group of R1, R2, R5 and R6 is an acrylate group. The non-radical polymerizable additive may be a surfactant. The curable composition may also include a curing agent.

Description

CROSS REFERENCES TO RELATED APPLICATIONS[0001]This application is a continuation application of U.S. patent application Ser. No. 15 / 898,687, filed Feb. 19, 2018, entitled “METHOD TO MAKE A PHOTOCONDUCTOR HAVING AN OVERCOAT WITH TETRAFUNCTIONAL RADICAL POLYMERIZABLE CHARGE TRANSPORT MOLECULE”, which is a continuation application of U.S. patent application Ser. No. 14 / 983,928, filed on Dec. 30, 2015, now U.S. Pat. No. 9,927,727 and issued Mar. 27, 2018, entitled “METHOD TO MAKE A PHOTOCONDUCTOR HAVING AN OVERCOAT WITH TETRAFUNCTIONAL RADICAL POLYMERIZABLE CHARGE TRANSPORT MOLECULES”, which is a continuation application of U.S. patent application Ser. No. 14 / 145,309, now U.S. Pat. No. 9,256,143, filed Dec. 31, 2013 and issued Feb. 9, 2016, entitled “PHOTOCONDUCTOR OVERCOAT HAVING TETRAFUNCTIONAL RADICAL POLYMERIZABLE CHARGE TRANSPORT MOLECULE”, all of which are assigned to the assignee of the present application.BACKGROUND1. Field of the Disclosure[0002]The present disclosure relates g...

AI Technical Summary

Benefits of technology

This patent is about an organic photoconductor drum that has a support element, a charge generation layer, a charge transport layer, and an overcoat layer. The overcoat layer includes a curable composition with a non-radical polymerizable additive and a charge transport molecule. The charge transport molecule has four radical polymerizable functional groups. The non-radical polymerizable additive is a surfactant, and the curable composition may also include a curing agent. The technical effect of this patent is to improve the performance and reliability of organic photoconductor drums by optimizing the composition of the overcoat layer.

Problems solved by technology

Therefore, the failure mechanism for organic photoconductor drums typically arises from mechanical abrasion of the surface layer due to repeated use.

Abrasion of photoconductor drum surface may arise from its interaction with print media (e.g. paper), paper dust, or other components of the electrophotographic image forming device.

The abrasion of the photoconductor drum surface degrades its electrical properties, such as sensitivity and charging properties.

Electrical degradation results in poor image quality, such as lower optical density, and background fouling.

When a photoconductor drum is locally abraded, images often have black toner bands due to the inability to hold charge in the thinner regions.

However, such overcoat layer does not have the robustness for edge wear of photoconductor drums used in mono printers.

If the overcoat layer is too electrically insulating, the photoconductor drum will not discharge and will result in a poor latent image.

On the other hand, if the overcoat layer is too electrically conducting, then the electrostatic latent image will spread resulting in a blurred image.

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