Ricoh Company, Ltd.

Toshio Fukagai

Kiyoshi Taniguchi

Toshiyuki Kabata

Masaomi Sasaki

Hiroshi Tamura

Naoshi Mishima

Kayoko Yokoyama

Mitsuru Hashimoto

Katsuichi Ohta

Tomohiro Inoue

Yoshio Watanabe

Junichi Yamazaki

Noriyuki Iwata

Minoru Umeda

Katsuhiko Tani

Yuka Miyamoto

Takuji Katoh

Hiroyuki Kishi

Tatsuya Katoh, Deceased

Kiyoshi Sakai

Masafumi Ohta

Yoshiaki Kawasaki

Takamichi Enomoto

Michio Kimura

Takeo Kazami

Kayoko Suzuki

Tatuya Kato

By Mankichi Katoh, Heir

By Mankichi Katoh, Legal Representative

An image forming method including charging an upper surface of a photoconductor having a photoconductive layer with a charger located in contact with or spaced apart a distance of not greater than 100 &mgr;m from the upper surface, and scanning the charged upper surface with a light beam having a wavelength of &lgr; &mgr;m and a spot diameter &phgr; &mgr;m to form an electrostatic latent image thereon. The upper surface of the photoconductor and a lower surface of the photoconductive layer have such roughness that the maximum heights in a unit length of &phgr; &mgr;m give minimum values R and R , respectively, satisfying the following conditions: R &lE;&lgr;/2n &mgr;m, R &lE;&lgr;/2n &mgr;m and (R &plus;R )&gE;&lgr;/2n &mgr;m.

Image forming method, image forming apparatus, process cartridge and photoconductor

An image forming method wherein a surface of a photoconductor having a photoconductive layer provided on a conductive support is scanned at least along a main scanning direction of the photoconductor with a writing light beam having a wavelength of &lgr; &mgr;m and a spot diameter &phgr; &mgr;m to form an electrostatic latent image thereon. The surface of the photoconductor has such a roughness that the sectional curve thereof along the main scanning direction is represented by a function y&equals;f(x) when the main scanning direction and the direction of the vertical height are assumed to be the X-axis and the Y-axis, respectively. The maximum height of the sectional curve in a region from an arbitral position x on the X-axis to a position (x&plus;&phgr;) on the X-axis is at least &lgr;/2n &mgr;m where n is a refractive index of the photoconductive layer at the wavelength of the light beam.

A photoreceptor including a support and a photosensitive layer formed thereon, optionally an undercoat layer between the support and the photosensitive layer, wherein when a group of data consisting of N samples of the height x(t) (&mgr;m) of a profile at the interface of the support on the side of the photosensitive layer, the interface of the photosensitive layer on the side of the support, and/or the interface of the undercoat layer on the side of the photosensitive layer, measured perpendicular to a horizontal direction of the support, taken at &Dgr;t (&mgr;m) intervals in the horizontal direction, is subjected to Fourier transformation in accordance with a formula as specified in the specification, in a power spectrum obtained by the Fourier transformation, I(S) represented by a formula specified in the specification has a particular value, a method of evaluating the above photoreceptor, a method of producing the photoreceptor, and an image formation apparatus in which the photoreceptor is incorporated are disclosed.

Photoreceptor, method of evaluating a photoreceptor, and method of producing the photoreceptor

A photoreceptor including a support and a photosensitive layer formed thereon, optionally an undercoat layer between the support and the photosensitive layer, wherein when a group of data consisting of N samples of the height x(t)(&mgr;m) of a profile at the interface of the support on the side of the photosensitive layer, the interface of the photosensitive layer on the side of the support, and/or the interface of the undercoat layer on the side of the photosensitive layer, measured perpendicular to a horizontal direction of the support, taken at &Dgr;t(&mgr;m) intervals in the horizontal direction, is subjected to Fourier transformation in accordance with a formula as specified in the specification, in a power spectrum obtained by the Fourier transformation, I(S) represented by a formula specified in the specification has a particular value, a method of evaluating the above photoreceptor, a method of producing the photoreceptor, and an image formation apparatus in which the photoreceptor is incorporated are disclosed.

Photoreceptor, method of evaluating the photoreceptor, method of producing the photoreceptor, and image formation apparatus using the photoreceptor

An image forming apparatus including a photoreceptor including a photosensitive layer on a surface of an electroconductive substrate and a light irradiator configured to irradiate the photoreceptor with a light beam having a wavelength &lgr; represented in units of micrometers and a diameter &phgr; represented in units of micrometers to form a dot latent image on the photoreceptor, wherein a maximum height in a part of a profile of the lower surface of the photosensitive layer in a sampling range of &phgr; is not less than &lgr;/(2n), where n is a refractive index of the photosensitive layer at the wavelength &lgr;.

Electrophotographic image forming apparatus, and photoreceptor therefor

A layered type electrophotographic photoconductor includes an electroconductive support; and a photoconductive layer formed thereon, which photoconductive layer contains a charge generation layer and a charge transport layer, which are overlaid, with the charge generation layer containing a polyalkylene glycol and/or a derivative thereof and/or a crown ether, and the charge transport layer containing an antioxidant. Alternatively, an undercoat layer may be interposed between the electroconductive support and the photoconductive layer, with the undercoat layer containing a polyalkylene glycol and/or a derivative thereof and/or a crown ether, and the charge transport layer containing an antioxidant.

Electrophotographic photoconductor

An electrophotographic photoconductor is composed of a substrate and a photoconductive layer formed thereon. The photoconductive layer is composed of a polymer including an acrylic acid ester moiety of formula (I) as repeat unit: ##STR1## wherein R.sup.1 represents hydrogen or a methyl group; R.sup.2, R.sup.3, and R.sup.4 each represent an alkyl group having 1 to 4 carbon atoms, a benzyl group, a phenyl group, a phenoxyl group, chlorine or bromine; n is an integer of 1 to 4; m is 0 to 1; and k is 0 or 1. The polymer and the monomer from which the polymer is prepared are synthesized.

Polymers of acrylic acid ester derivatives having a triphenyl amine

An electrophotographic photoconductor is composed of a substrate and a photoconductive layer formed thereon. The photoconductive layer is composed of a polymer including an acrylic acid ester moiety of formula (I) as repeat unit: ##STR1## wherein R.sup.1 represents hydrogen or a methyl group; R.sup.2, R.sup.3, and R.sup.4 each represent an alkyl group having 1 to 4 carbon atoms, a benzyl group, a phenyl group, a phenoxyl group, chlorine or bromine; n is an integer of 1 to 4; m is 0 or 1; and k is 0 or 1. The polymer and the monomer from which the polymer is prepared are synthesized.

Acrylic acid ester derivative having a triphenyl amine skeleton

An electrophotographic photoconductor composed of an electroconductive substrate and a photoconductive layer formed thereon, containing an interpenetrating polymer network prepared by polymerizing a composition composed of a binder resin and at least one polymerizable carbon-carbon double-bond-containing charge transporting monomer selected from the group consisting of monomers of formulas (I), (II) and (III) by the application of light or heat thereto: ##STR1##

Electrophotographic Photoconductor

An electrophotographic image formation method using an electrophotographic photoconductor composed of an electroconductive support, and a photoconductive layer including a charge generation layer and a charge transport layer which are successively overlaid on the support, having the steps of charging the surface of the electrophotographic photoconductor uniformly to a predetermined polarity, exposing the charged surface of the photoconductor to light images to form electrostatic latent images thereon, developing the electrostatic latent images to visible toner images by a developer, transferring the toner images to an image-receiving medium, and cleaning the surface of the photoconductor, with the concentration of ozone in the ambient atmosphere around the photoconductor being controlled in the range from 5 to 50 ppm, and the abrasion of the photoconductive layer being controlled to 300 .ANG. or less per 1000 revolutions of the photoconductor.

Electrophotographic image formation method

Electrophotographic photoconductor and acrylic acid ester polymer for

An electrophotographic photoconductor is disclosed, which comprises an electroconductive substrate, an undercoat layer formed on the electroconductive substrate, and a photoconductive layer comprising a charge generation layer and a charge transport layer formed on the undercoat layer, wherein the undercoat layer comprises a binder resin and a modified indium oxide having exothermic peaks in the range of 200.degree. to 600.degree. C. detected by the differential thermal analysis, which modified indium oxide is prepared by pretreatment with a hydroxyl-group-containing compound, an amino-group-containing compound, or an ether-group-containing compound.

Electrophotographic photoconductor having intermediate layer comprising

An electrophotographic photoconductor is disclosed, which comprises an electroconductive support, a photoconductive layer formed on the electroconductive support, and an overcoat layer formed on the photoconductive layer, in which the overcoat layer comprises a binder resin and one component selected from the group consisting of a crown ether, a polyalkylene glycol, a polyalkylene glycol ester and a polyalkylene glycol ether. The overcoat layer may be composed of an intermediate layer formed on the photoconductive layer, and a protective layer formed on the intermediate layer in such a manner that any of the crown ether and polyalkylene glycol derivatives is contained in the intermediate layer.

Electrophotographic photoconductor having overcoat layer

An electrophotographic photoconductor which comprises an electroconductive support; an undercoat layer formed thereon comprising (i) a reaction product between an active-hydrogen-containing compound having a plurality of active hydrogens and an isocyanate-group-containing compound, which reaction product serves as a binder resin, and (ii) finely-divided particles of indium oxide dispersed in the reaction product; and a photo-sensitive layer formed on the undercoat layer. The indium oxide may be partly replaced by metal oxide, metal fluoride, metal nitride, metal carbide or metal boride in an amount of not more than 50 wt. %.

An electrophotographic photoconductor is disclosed, which comprises an electroconductive support, an undercoat layer formed on the electroconductive support, comprising at least one metal oxide selected from the group consisting of zirconium oxide, magnesium oxide, calcium oxide, beryllium oxide and lanthanum oxide, and a photoconductive layer comprising a charge generating layer and a charge transporting layer, formed on the undercoat layer.

Growing community of inventors

Numazu, Japan

Toshio Fukagai