Kyocera Mita Corporation

Kyocera Document Solutions Inc.

Daisuke Kuboshima

Kazunari Hamasaki

Jun Azuma

Keiji Maruo

Yoshio Inagaki

Yuko Iwashita

Norio Nakai

Eiichi Miyamoto

Hideki Okada

Junichiro Otsubo

Tetsuya Ichiguchi

Mitsuo Ihara

Hisakazu Honma

Shiho Kuboshima

Yukimasa Watanabe

Susumu Hiroshima

Hirofumi Kawaguchi

Maki Uchida

Yukikatsu Imanaka

Hiromi Nakatsu

Teruyo Taguchi

Provided is a monolayer type photoconductor superior in sensitivity characteristics that allows reliable production by easy confirmation of the sensitivity characteristics, and an image forming device using such a monolayer type photoconductor. A monolayer type photoconductor including a base body and a single photo sensitive layer formed on the base body, the single photo sensitive layer containing a charge generating agent, a hole transfer agent, an electron transfer agent and a binding resin, wherein a maximum absorption wavelength (&#x3bb;) of the photo sensitive layer is set to a value of below 850 nm and an absorbance (A) of light at a wavelength of 850 nm per unit thickness of the photo sensitive layer is set to a value of 0.05 &#x3bc;mor less.

Monolayer type photoconductor and image forming device

The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor. The oxo-titanylphthalocyanine crystal has predetermined optical characteristics and thermal properties and is produced by a production method including the following steps (a) to (d): (a) a step of dissolving a crude oxo-titanylphthalocyanine crystal in an acid to obtain an oxo-titanylphthalocyanine solution; (b) a step of adding the oxo-titanylphthalocyanine solution dropwise in a poor solvent to obtain a wet cake; (c) a step of washing the wet cake with an alcohol having 1 to 4 carbon atoms; and (d) a step of stirring the washed wet cake under heating in a nonaqueous solvent to obtain an oxo-titanylphthalocyanine crystal.

Oxo-titanylphthalocyanine crystal, method for producing the same and electrophotographic photoreceptor

The present invention provides an electrophotographic photoreceptor comprising a photosensitive layer that contains at least a charge generating agent, a hole transport agent and a prede mulas (A) and (B). The electrophotographic photoreceptor prevents image defect termined additive. The hole transport agent satisfies the following for from occurring and can meet the demand for higher speed image forming apparatuses, by reducing the adhesion of paper dust and preventing the occurrence of cracks. 

Electrophotographic photoreceptor and image forming apparatus

Oxo-titanylphthalocyanine crystal, method for producing the same, and electrophotographic photoreceptor

The present invention provides a monolayer type electrophotographic photoconductor which can effectively suppress the generation of an exposure memory and exhibits high sensitivity and an image forming apparatus using the monolayer type electrophotographic photoconductor. In an electrophotographic photoconductor which has a monolayer type photoconductive layer including at least a charge generating agent, a hole transfer agent, an electron transfer agent and a binding resin on a substrate, the charge generating agent contains oxo-titanyl phthalocyanine crystal, the electron transfer agent has a reduction potential thereof set to a value which falls within a range from &#x2212;0.97 to &#x2212;0.83 V, and the reflection absorbance (A/&#x2212;) of the photoconductive layer with respect to light having a wavelength of 700 nm, a film thickness (d/m) of the photoconductive layer, and the concentration (C/weight %) of the oxo-titanyl phthalocyanine crystal of the photoconductive layer (100 weight %) satisfy a following formula (1).&#x3e;1.75&#xd7;10&#x2003;&#x2003;(1)

Electrophotographic photoconductor having titanyl phthalocyanine and image forming apparatus

The present invention provides an electrophotographic photoconductive member comprising a substrate, and a photoconductive layer containing a hole transferring material, a charge generating material and a binder resin, wherein a value (IV/OV value) in which the inorganic value is divided by the organic value of the binder resin is 0.36 or more and the hole transferring material contains an amine compound represented by the following general formula (1): 

Electrophotographic photoconductive member and image forming apparatus

An electrophotographic photoconductor having an excellent crack resistance and wear resistance as well as excellent sensitivity characteristics, while keeping good image characteristics of the photoconductor is provided. In addition, an image-forming apparatus equipped with such an electrophotographic photoconductor is also provided. The electrophotographic photoconductor includes a photosensitive layer containing at least a charge-generating agent, a hole-transfer agent, and a binder resin on a conductive substrate. The hole-transfer agent has a solubility of 5 to 35% by weight with respect to triglyceride oleate and the photosensitive layer contains a compound represented by the following general formula (1) as an additive: 

Electrophotographic photoconductor and image-forming apparatus

The present invention provides a single layer type electrophotographic photoconductor which exhibits the small number of generated black spots in a formed image and exhibits the excellent sensitivity characteristic even when the photoconductor is used for a long time or a photoconductor drum is rotated at a high speed and an image display device which includes the single layer type electrophotographic photoconductor. In the single layer type electrophotographic photoconductor which includes a photoconductive layer containing a binding resin, a hole transporting agent and an charge generating agent, the photoconductor contains a water-repellant polycarbonate resin as the binding resin, and a contact angle of pure water (measured temperature: 25&#xb0; C.) with respect to the photoconductive layer is set to 100&#xb0; or more.

Single layer type electrophotographic photoconductor and image forming device

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

Stilbeneamine derivative and electrophotosensitive material using the same

The present invention relates to a titanyl phthalocyanine crystal having excellent storage stability of coating solution, to satisfy that (a) the crystal does not have a peak of a change in temperature except for a peak associated with evaporation of adsorbed water in differential scanning calorimetry or that (b) the crystal recovered after dipping in an organic solvent for 24 hours at least a maximum peak at a Bragg angle 2&thgr;&plusmn;0.2&deg;&equals;27.2&deg; and has no peak at 26.2&deg; in a CuK &agr; characteristic X-ray diffraction spectrum, and a method of producing the same; and an electrophotosensitive material using the above crystal, and a method of producing the same.

Growing community of inventors

Osaka, Japan

Daisuke Kuboshima