Sharp Kabushiki Kaisha Corporation

Sharp Corporation

Mitsubishi Kasei Corporation

Sharp Kabushiki

Mitsubhishi Kasei Corporation

Kunio Ohashi

Takashi Hayakawa

Shoichi Nagata

Syoichi Nagata

Shiro Narikawa

Yoshiharu Tsujimoto

Masatsugu Nakamura

Mitsuru Tokuyama

Tadashi Tonegawa

Kazuki Wakita

Yoshikazu Fujiwara

Hiroshi Kinashi

Hiromu Sasaki

Katsuhiro Nagayama

Toshiaki Ino

Mamoru Nozomi

Motoyuki Itoyama

Tadashi Umehara

Toshiya Asari

Eiichi Kido

Toshiaki Kobayashi

Mitsuru Ogura

Haruo Nishiyama

Shunju Anzai

Shougo Iwai

Hiroshi Mori

Yoshiaki Imanaka

Ikuo Itoh

Kazuo Maeyama

Hidenobu Yamane

Osamu Hashimoto

Yoshikazy Fujiwara

Shiro Narukawa

An electrophotographic photoreceptor comprising a cylindrical electrically conductive substrate having thereon at least a photoconductive layer, the conductive substrate having a marking portion in which the light reflectance of the surface of the conductor substrate has been changed by a laser light treatment, a method for producing the photoreceptor, and an image correcting method using the photoreceptor.

Electrophotographic photoreceptor and method for producing the

Image correcting method using an electrophotographic photoreceptor

A process control apparatus of electrophotographic apparatus has an optical sensor for optically detecting the density of toner patches formed on a photoreceptor drum. The present apparatus is further provided with a control device for controlling lamps for the copying process, chargers and other elements. A toner patch is formed on the photoreceptor so as to be located between every two toner images for a copying operation. The control device controls the lamps, chargers and other elements in accordance with the result of the toner patches detected by the optical sensor so as to stabilize the copying picture quality. With the arrangement, it is avoided that the job efficiency during the copying operation deteriorates, and the control data obtained from the toner patches is soon used for the toner image formation for the copying operation, thereby ensuring that the process control improves in accuracy.

Electrophotographic image stabilization control apparatus

An apparatus includes a system controller which calculates a ratio of a first signal to a second signal and adjusts a control parameter of an electrophotographic reproduction process so that the density of fog indicated by the ratio is within a predetermined range. A first optical sensor outputs the first signal by detecting a reflectance of a non-image area on the photoreceptor between a developing unit and a transfer charger. A second optical sensor outputs the second signal by detecting a reflectance of a surface of the photoreceptor between a cleaning unit and a charger. The system controller controls developer including toner and carrier to be agitated when the ratio obtained after adjusting the control parameter is still outside the predetermined range. Since the density of fog is detected with accuracy by calculating the ratio, copy quality is stabilized even when temperature changes. Moreover, even if the ratio is outside the predetermined range as a result of the supply of toner which has deteriorated due to a heat history, the deterioration of toner is restored by agitating the developer. It is thus possible to prevent copy quality from being degraded.

Electrophotographic reproduction apparatus controllable toner density

The present invention provides a process control stabilizing system including a cleaning device for the corona wires which allows the process control to be carried out optimally based on exact information which is obtained by certain sensors while a discharge from the main charger unit is kept uniform. The system is constructed so that an electrode cleaner is activated before the detection of the surface potential and/or the detection of the optical density, and in addition, the cleaning operation will be operated until the detection result falls within a predetermined range. Alternatively, the system causes detection of the surface potential and/or detection of the optical both before and after a cleaning operation by the electrode cleaner. The cleaning operation will be repeated until the difference between the first and second detections falls within a predetermined range. In the above operations, if the repetitions of the operations in excess of the predetermined number of times cannot make the detection result fall within the predetermined range, the system preferably activates a warning device and/or prohibits a copying operation.

Process control stabilizing system including a cleaning device for the

A photosensitive sheet comprising a sheet-shaped substrate, one surface of which is coated with a light-reflective substance or which is made of a light-reflective substance, and pressure-rupturable capsules that coat the light-reflective surface of the substrate or the other surface of the substrate, the pressure-rupturable capsules containing chromogenic materials and photosensitive materials that are hardened when illustrated with light, and a method for the formation of images using the said photosensitive sheet.

Photosensitive sheet and a method for the formation of images using the

A photoconductor coupled liquid crystal light valve comprising a photoconductor layer, a liquid crystal layer and electrodes for applying voltage to the layers. The photoconductive layer is made of amorphous silicon containing hydrogen and/or halogen at more than 40 at%. The photoconductive layer preferably has a resistivity of between 10.sup.11 and 10.sup.12 ohm-cm and a photonconductivity of 10.sup.-8 and 10.sup.-6 cm.sup.2 /V. The photoconductive layer is preferably formed by electron cyclotron resonance.

Liquid crystal light valve with amorphous silicon photoconductor of

An image forming apparatus makes use of a photosensitive sheet having a surface coated with microcapsules encapsulating a light-curable agent and a colorless dye and an image transfer sheet having one surface coated with a developing agent having an chromogenic effect on the encapsulated colorless dye. These sheets are superposed one on top of the other and pressed together by a compression device to selectively rupture the microcapsules on the photosensitive sheet, forming a visible image on the image transfer sheet which is thereafter heated by a heating device. Either the speed at which the image transfer sheet is passed through the compression device or the temperature at which the image transfer sheet is heated by the heating device is controlled according to a characteristic of the image transfer sheet such as its thickness, electrostatic capacity and light transmissivity.

Image forming apparatus

A method for image formation comprising the steps of exposing a light-receiving sheet coated with a layer of microcapsules containing photopolymerization agent and colorless dye selectively to light so as to form a cured image thereon opposite in sense to the desired final image, laying an image-receiving sheet uniformly coated with a layer of a developing material for reacting with and coloring the colorless dye on the light-receiving sheet, heating the resulting sandwich configuration and pressing these sheets against each other thereby rupturing the uncured microcapsules to form a colored image.

Image forming method combining heat and pressure to produce a color image

A photosensitive body for electrophotography has as its principal constituent a photoconductive layer having amorphous silicon with hydrogen, a surface layer having a greater optical band gap than the photoconductive layer formed on a photoconductive base member, and an intermediate layer sandwiched therebetween.

Photosensitive body for electrophotography containing amorphous silicon

An improved photosensitive member for electrophotography which comprises an intermediate layer, a photoconductive layer and a surface protecting layer each formed upwardly in this order on a conductive substrate, the photoconductive layer comprising a non-doped a-Si layer made of a amorphous silicon containing hydrogen and/or halogen of 40 at. % or more.

Photosensitive member for electrophotography

An image forming apparatus comprising an optical device for forming a latent image on a photo and pressure sensitive sheet coated with microcapsules in which at least a photocuring material and a dyestuff are enveloped, a pressure developing device for superposing the photo and pressure sensitive sheet on which the latent image is formed on an image receiving sheet and breaking uncured microcapsules by pressure to form images on the image receiving sheet through use of the dyestuff, a light source for irradiating light on the image receiving sheet developed by the pressure developing device and a discharge device for discharging the image receiving sheet on which the light from the light source is irradiated to the outside.

A photosensitive member for electrophotography which comprises a conductive substrate and a photoconductive layer which is composed of an amorphous silicon layer and an amorphous silicon germanium layer containing a specific amount of hydrogen and/or halogen respectively, and being prepared by electron cyclotron resonance method respectively, which is useful for xerographic systems.

Amorphous, layered, photosensitive member for electrophotography and ECR

A digital picture image forming apparatus is disclosed which includes a media sheet coated with micro-capsules, each of which contains one of the dyes capable of coloring to yellow, magenta and cyan and curable by irradiating to one of blue, green and red light. It further includes an optical system for irradiating to the media sheet a blue, green or red light including digital picture image information, to form latent images on the media sheet. Finally, a device for pressing an image receiving sheet on the irradiated media sheet and rupturing the uncured micro-capsules is included to form a picture image information on the image receiving sheet. Further the three colors of digital picture image information light do not contain cross talk wavelength ranges overlapping with each other.

Digital picture image forming apparatus for eliminating cross talk

Image-forming light from a light source is projected to form a latent image with color information on a photosensitive sheet having a surface coated with microcapsules each containing a light-curable agent sensitive to light in a wavelength range corresponding to blue, green or red and a specified chromogenic agent which produces yellow, magenta or cyanic. An image transfer sheet with a surface coated with a developing agent having chromogenic effects on these encapsulated chromogenic agents is superposed on such a photosensitive sheet with a latent image formed thereon by selectively hardened microcapsules and these sheets are compressed together to rupture only those of the microcapsules which have not been hardened. The emission characteristics of the lamp used as the light source are such that the emission intensity is concentrated in wavelength ranges where the light-curable agents have peak photosensitivities.

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Nara, Japan

Kunio Ohashi