Sharp Kabushiki Kaisha Corporation

Kotaro Fukushima

Koichi Toriyama

Hisayuki Utsumi

Tomoko Kanazawa

Takatsugu Obata

Akiko Kihara

Kohichi Toriyama

Takahiro Kurauchi

Satoshi Katayama

Akihiro Kondoh

Mikio Kakui

Junichi Washo

Rikiya Matsuo

Mami Adachi

Katsuya Takano

Chikako Iibachi

Masaki Hashimoto

Masanori Matsumoto

Hiroshi Sugimura

Katsuru Matsumoto

Takayuki Yamanaka

Tatsuhiro Morita

Shinya Mimura

Sayaka Fujita

Yohichi Takesawa

Takuya Arimura

Kimiko Kumazawa

Akiko Uchino

The present invention provides an electrophotographic photoreceptor comprising a multilayered photosensitive layer or a monolayer photosensitive layer,

Electrophotographic photoreceptor and image forming apparatus provided with the same

An electrophotographic photoreceptor having a photosensitive layer formed on a conductive substrate, wherein the photosensitive layer contains oxygen-containing fluorinated fine particles in a surface layer thereof, and the oxygen-containing fluorinated fine particles have an oxygen composition ratio of 0.9 to 3.0% by atom based on the whole composition of the fine particles according to an X-ray fluorescence composition analysis.

Electrophotographic photoreceptor and image forming apparatus including the same

A coating liquid for an undercoat layer of an electrophotographic photoreceptor which is formed by sequentially stacking the undercoat layer and a photosensitive layer on an electrically conductive support, wherein the coating liquid comprises titanium oxide microparticles and silicon nitride microparticles as an inorganic compound, a binder resin and an organic solvent.

Electrophotographic photoreceptor, coating liquid for undercoat layer of electrophotographic photoreceptor, and method for producing the same

An electrophotographic photoconductor of the invention comprising: an conductive support; a light-sensitive layer formed on the conductive support and containing a charge generating material and a charge transport material; and a surface protective layer formed on the light-sensitive layer and made of a resin composition, wherein the resin composition constituting the surface protective layer contains an amine compound represented by the following formula (1):  wherein R1 and R2 are, the same or different, each an alkyl group or an allyl group which may have a substituent or a heterocyclic residue to be formed through or not through a nitrogen atom or an oxygen atom together with the nitrogen atom to which R1 and R2 are bonded, R3 and R4 are, the same or different, each an alkyl group having a substituent and n denotes 1 or 2, provided that when n is 1, X is a hydrogen atom, a halogen atom, or an alkyl group, a hydroxyl group or a mercapto group which may have a substituent, or a ring optionally containing an oxygen atom and a nitrogen atom between carbon atoms and when n is 2, X is an oxygen atom or a sulfur atom.

Electrophotographic photoconductor, method of producing the same and image forming apparatus

An electrophotographic photoreceptor comprising a layered-type photosensitive layer in which a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material are stacked, formed on a conductive supporting member made of a conductive material, wherein the electrophotographic photoreceptor has high sensitive characteristics to a semiconductor laser beam having a wavelength ranging from 380 to 500 nm; the charge transporting layer of the layered-type photosensitive layer contains as the charge transporting material, a triarylamine dimer compound represented by the general formula (1): wherein Arand Armay be the same or different, and represent an unsubstituted or substituted arylene group or heterocyclic derivative bivalent group, Arand Armay be the same or different, and represent an unsubstituted or substituted aryl group or heterocyclic group, Rand Rmay be the same or different, and represent an alkyl group, m and n represent an integer of 1 to 4, a and b may be the same of different, and represent a hydrogen atom, a halogen atom, or unsubstituted or substituted alkyl group, alkoxy group or amino group;and a film thickness of the photosensitive layer is 30 &#x3bc;m or less.

Electrophotographic photoreceptor, image forming apparatus and process cartridge

The present invention therefore provides an image forming apparatus, comprising: a photoconductor; a charge means for charging the photoconductor; an exposure means for irradiating a surface of the photoconductor with light to form an electrostatic latent image; a development means for developing the electrostatic latent image formed; a transfer means for transferring the image developed onto a paper sheet; and a discharge means for irradiating the surface of the photoconductor with light to eliminate charges, wherein the photoconductor contains a titanylphthalocyanine having absorption bands in a wavelength region of 380 nm to 420 nm and a wavelength region of 600 nm to 850 nm as a charge generation material, the exposure means irradiates the surface of the photoconductor with light having a wavelength of 380 nm to 420 nm to form the electrostatic latent image, and the discharge means irradiates the surface of the photoconductor with light having a wavelength of 600 nm to 850 nm to eliminate the charges.

Image forming apparatus having a photoconductor containing titanylphthalocyanine

An electrophotographic photoreceptor comprising at least a photosensitive layer formed by laminating a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material in this order, on a conductive support, wherein the charge generation layer contains an oxotitanylphthalocyanine as the charge generation material and metal oxide microparticles, and the electrophotographic photoreceptor has photosensitive properties in light source of wavelength range from 360 to 420 nm.

Electrophotographic photoreceptor and image formation device provided with the same

An electrophotographic photoreceptor comprising a conductive support and a photosensitive layer obtained by laminating at least a charge generation layer and a charge transport layer containing a charge transport material in this order on the conductive support, the photosensitive layer being provided with a surface protective layer on the surface thereof, wherein the protective layer contains at least filler particles which exhibit a dispersed state defined by Rf given by the following equations (1) and (2):=()/()&#x2003;&#x2003;(1)1.0&#xd7;10&#x2266;2.5&#xd7;10&#x2003;&#x2003;(2)and a diamine compound represented by the following formula (I): 

An image forming apparatus having excellent cleaning property for an electrophotographic photoreceptor and capable of forming a high-quality, high-resolution image. A surface free energy (&#x3b3;) of a photoreceptor (), which is provided in the image forming apparatus (), is set to 20 to 35 mN/m. A volume average diameter of toner particles included in a developer stored in a developing unit () to develop an electrostatic latent image and form a toner image is set to 4-7 &#x3bc;m When &#x3b3; of the photoreceptor () is set to within a small range as the particle size of toner is reduced, even small-particle-size toner having increased specific surface area and largely affected by a inter-molecular force is limited in adhesion to the surface of the photoreceptor () to provide a good cleaning property and a high-quality image can be formed.

Image forming apparatus equipped with an electrographic photoreceptor having a surface with low surface free energy

An electrophotographic photoconductor containing a conductive substrate and at least a charge generating layer and a charge transporting layer successively layered on the substrate, wherein the charge transporting layer contains a charge transporting material (M) and a binder resin (B) and further has a layered structure composed of a plurality of the charge transporting layers wherein the outermost layer of the charge transporting layers show 50% or higher elastic power (&#x3b7;) and hardness (Hplast) of plastic deformation in a range from 220 N/mmor higher to 275 N/mmor lower.

Electrophotographic photoconductor

An electrophotographic photoreceptor having an organic photosensitive layer at the surface layer is provided which can improve the wear resistance, durability and operation stability of the surface layer and can form images with no injury and unevenness in the density for a long period of time. The electrophotographic photoreceptor includes a conductive substrate, an undercoat layer, and a photosensitive layer having a charge generating layer and a charge transporting layer. In the photoreceptor, the photosensitive layer has a creep value Cof 2.70% or more and an elastic ratio &#x3b7;of 47% or more in a case where an indentation maximum load of 5 mN is loaded on the surface under a circumstance at a temperature of 25&#xb0; C. and at a relatively humidity of 50%.

Electrophotographic photoreceptor and image forming apparatus

An electrophotographic photoreceptor having excellent electric characteristics such as sensitivity characteristic and light responsiveness with an excellent life duration of abrasion resistance so that no flaw and density unevenness are generated on to-be-formed images for a long period of time, is provided. In an electrophotographic photoreceptor (), an enamine compound represented by the following general formula (1), for example, an enamine compound represented by the following structural formula (1-1) is contained in a charge transporting layer (), and a creep value (C) in a case where a maximum indentation load of 30 mN is put on a surface for 5 seconds under circumstances of temperature of 25&#xb0; C. and relative humidity of 50%, is set to 2.70% or more and 5.00% or less, and a plastic deformation hardness value (Hplast) of the surface is set to 220 N/mmor more and 275 N/mmor less. 

An electrophotographic photoreceptor of excellent durability having high sensitivity and light responsiveness, not suffering from lowering of the electric characteristics by exposure to light, change of circumstance, or repetitive use, and excellent in the cleaning property and not suffering from lowering of the picture quality of formed images for a long times, in which an enamine compound represented by the general formula (1), for example, an enamine compound represented by the following structural formula (1-1) is incorporated in a photosensitive layer, and the surface energy (&#x3b3;) on the surface of the photosensitive layeris set to 20.0 mN/m or more and 35.0 mN/m or less, the electrophotographic photoreceptor: 

An electrophotographic photoreceptor is provided that in excellent in the electrical characteristics such as the charging property, the sensitivity and the responsiveness, the oxidizing gas resistance such as the ozone resistance and the nitrogen oxide resistance, and the electrical durability such that even after repetition use the foregoing excellent electrical characteristics are not deteriorated. A photosensitive layer of an electrophotographic photoreceptor contains an amine compound represented by the general formula (1). 

Growing community of inventors

Kawanishi, Japan

Kotaro Fukushima