Kyocera Mita Corporation

Hisakazu Honma

Jun Azuma

Yukimasa Watanabe

Ayako Yashima

Eiichi Miyamoto

Kazunari Hamasaki

Kyoichi Nakamura

Daisuke Kuboshima

Maki Uchida

The present invention provides an electrophotosensitive material which realizes uniform dispersion of phthalocyanines in a photosensitive layer and has high sensitivity to a digital light source, and also excellent in charge stability under the high temperature atmosphere, weatherability and NOx resistance. The electrophotosensitive material is produced by forming a single-layer type or multi-layer type photosensitive layer containing phthalocyanine as an electric charge generating material, an electric charge transferring material, a predetermined insoluble azo pigment and a predetermined binder resin on a conductive substrate and using, as the insoluble azo pigment, an insoluble azo pigment having no OH group in the molecule wherein (i) an absorbance in an absorption wavelength range of phthalocyanine is &#x2153; or less of an absorbance of the phthalocyanine in the wavelength range, or (ii) an absorbance in a wavelength range of an exposure light source of an image forming apparatus is &#x2153; or less of an absorbance of the phthalocyanine in the wavelength range.

Electrophotosensitive material

The present invention relates to a novel titanyl phthalocyanine crystal which can prepare a coating solution having excellent storage stability because it satisfies both of the following two characteristics (a) and (b), a method of producing the same, an electrophotosensitive material using the above crystal as an electric charge generating material.

Titanyl phthalocyanine crystal and production method of the same, and electrophotosensitive material

A single-layer type electrophotosensitive material comprising a conductive substrate and a photosensitive layer made of a binder resin containing at least an electric charge generating material and a hole transferring material and an electron transferring material as an electric charge transferring material, which is formed on the conductive substrate, characterized in that the binder resin contains a polycarbonate resin having a repeating structural unit represented by the general formula &lsqb;1&rsqb; and the solid content of the hole transferring material and the electron transferring material is not less than 30% by weight and not more than 50% by weight relative to the entire solid content, exhibits good wear resistance with respect to the photosensitive layer and is also superior in durability.

Single-layer type electrophotosensitive material

Disclosed is a single-layer type electrophotosensitive material comprising a conductive substrate and a photosensitive layer made of a binder resin containing at least an electric charge generating material and an electric charge transferring material, which is formed on the conductive substrate, wherein an oxygen transmission rate of the binder resin is not more than 35 cc&middot;mm/m &middot;day&middot;atom, wherein it is preferred that a mobility at an electric field strength of 5&times;10 V/cm of the hole transferring material is not less than 5&times;10 cm /V/sec and a solid content of the electric charge transferring material is not less than 30% by weight and not more than 50% by weight based on the whole solid content; said electrophotosensitive material has good ozone resistance and does not cause defects such as image black belt due to lowering of the charge capability, an ozone of which is 5.0 ppm at most, and is also superior in sensitivity and wear resistance.

Growing community of inventors

Osaka, Japan

Hisakazu Honma