Ricoh Company, Ltd.

Itsuo Ikeda

Tsuneo Kurotori

Manabu Mochizuki

Ichiro Tsuruoka

Katsuhiro Echigo

Yoshihiro Sakai

Katsuo Sakai

Hiroshi Tanabe

Hideya Furuta

Yuji Sawai

Minoru Iwamoto

Satoshi Shinguryo

Tsukasa Adachi

Mayumi Miyao

Seiichi Miyagawa

Hiroshi Goto

Yutaka Koizumi

Kenji Kojima

Noriyoshi Tarumi

Shigeru Suzuki

Masaru Shimada

Makoto Obu

Yusuke Takeda

Wasaburo Ohta

Seiichi Miyakawa

Kenzo Ariyama

Sadayuki Iwai

Mitsuo Hasebe

Koji Hirakura

Junji Kurokawa

Tadashi Fujii

Mitsuru Mamizuka

Toshio Inada

Eiichi Akutsu

Yuichi Kobayashi

Haruhiko Fukuda

Mitsuhiro Nonaka

Zenjiro Okuno

By Noriko Tsuiki, A Legal Representative

Tsuiki, Deceased Harunobu

Hisayuki Ushiyama

Manami Tsuiki, Legal Representive

Tomohiro Tsuiki, Legal Representive

Hajime Hariu

In an image forming apparatus, a fixing device fixes a toner image transferred to a sheet, but held in an unstable state, temporarily on the sheet by a Johnson Rahbeck effect. The fixed image firmly adhere to the sheet and is free from disturbance or suffers from a minimum of disturbance.

Image forming apparatus and fixing device therefor

An apparatus for displaying a recording medium sheet and for printing an image thereon includes a plurality of sheets each of which is made of an erasable recording medium, a recording unit for recording information on one of the plurality of sheets, a displaying unit for displaying the sheet on which information is recorded by the recording unit, the sheet being set at a display position when it is displayed, a sheet supplying unit for supplying one of the sheets to the recording unit, and for receiving the displayed sheet from the displaying unit, a sheet passage in which one of the sheets is transported from the displaying unit to the sheet supplying unit via the recording unit, and a sheet passage in which the sheet is transported from the sheet supplying unit to the displaying unit via the recording unit.

Apparatus for displaying a recording medium sheet and printing an image

A wet-type image formation apparatus comprising a latent electrostatic image formation unit capable of forming on a latent-electrostatic-image-bearable photoconductive member a latent electrostatic image corresponding to an original image; and a wet-type development unit capable of developing the latent electrostatic image into a visible toner image with a liquid developer composed of (i) a carrier liquid comprising a petroleum aliphatic hydrocarbon and a silicone oil with a siloxane structure, and (ii) toner particles comprising a coloring agent and a binder resin, which are dispersed in the above-mentioned carrier liquid.

Wet-type image formation apparatus

An image-receiving sheet for use with an electrophotographic method, including a transparent support and an overcoat layer formed thereon is disclosed, in which the overcoat layer (i) includes a thermoplastic resin which has a fluidification initiation temperature lower than that of a toner for image formation to be employed or that of a resin for use in said toner, and (ii) is white and opaque from being in a porous state. Furthermore, an electrophotographic method using the above image-receiving sheet is also disclosed.

Image-receiving sheet for electrophotography and electrophotographic

A control device for image forming equipment capable of reducing ozone ascribable to an image forming process and detecting failures of the equipment caused by the ozone. Mists are produced from a liquid developer which is a toner-dispersed carrier liquid containing silicone oil during developing, image transferring and fixing steps. The mists and the ozone are discharged to the outside of the equipment by a fan. A filter liquifies the mists and ozone by mixing them together. Errors are detected on the basis of ozone concentration which is sensed by an ozone concentration sensor.

Image forming apparatus with ozone detection and deodorizer

An image formation apparatus including a latent electrostatic image formation unit for forming on a latent-electrostatic-image-bearable photoconductive member a latent electrostatic image corresponding to an original image; a development unit for developing the latent electrostatic image into a visible toner image with a developer; an image-transfer unit for transferring the visible toner image from the photoconductive member to a transfer sheet; an image-fixing unit for fixing the visible toner image to the transfer sheet, including an image fixing roller, the surface of which is coated with a release agent comprising a silicone oil; a solvent mist generation unit for generating a solvent mist; and an ozone decomposing unit for trapping and decomposing ozone generated in the image formation apparatus by mixing the ozone with the solvent mist.

Apparatus for decomposing ozone by using a solvent mist

In a wet-type image formation apparatus, a latent electrostatic image formation unit; a wet-type development unit for developing a latent electrostatic image into a visible toner image with a liquid developer constituted of (a) a carrier liquid constituted of or including a silicone oil with a siloxane structure and (b) toner particles constituted of or including a coloring agent and a binder resin, which are dispersed in the carrier liquid; an image-transfer unit; and an image-fixing unit including a heat-application roller, the surface of which is coated with a release agent constituted of or including silicone oil with a siloxane structure.

Apparatus for forming and developing latent electrostatic images with

A developing device for developing an electrostatic latent image formed on an imaging surface includes a developing electrode disposed opposite to the imaging surface and a control circuit for controlling the potential of the developing electrode. In one form, when the control circuit causes the developing electrode to be electrically floating, the upper limit of the voltage excursion is set at different levels as desired. In another form, the control circuit includes a sensor for sensing the potential of the imaging surface thereby allowing to carry out so-called fixed bias or auto-bias developing modes. In a further form, the mode of developing operation is automatically set depending upon the position of a pressure plate which is to be placed on an original for keeping the original in position during copying process.

Developing device

A method of and an apparatus for producing duplicates of a document in color wherein a plurality of photosensitive members in drum form are rotated in the same direction and exposed to respective color-separated optical images of the document through respective arrays of gradient-index rod lenses to form electrostatic latent images on the photosensitive members while the document is supported on a document support member and moved in the same direction as the rotation of the photosensitive drums. The electrostatic latent images on the photosensitive members are developed in different colors into visible images of different colors which are printed by transfer-printing on a sheet of support material on a transfer-printing belt moved in a direction opposite the direction of movement of the document support member for light exposure of the photosensitive members. The speed at which the document support member is moved to its starting position in return movement is lower than the speed at which it starts from its starting position for light exposure of the photosensitive members.

Method of and apparatus for producing duplicates in color

Multicolored image forming apparatus wherein image processing is accomplished by exposing a photosensitive drum through an exposure optical device to the reflected light beam from the document illuminated with a lamp, reading the document image by an image sensor, energizing, by means of the processed signal of the output of the sensor, each LED in an eraser consisting of an LED array offset from the exposure slit center along the photosensitive drum in the width direction thereof, and erasing it. The light source simultaneously illuminates the document illumination position for slit exposure and a position offset from its center by a distance equal to the displacement between said erase position and the exposure position. The image sensor receives the light beam reflected from the document.

Multicolored image forming apparatus

A solid state corona discharger in corona chargers which charge and discharge photosensitive members in electrophotographic copying machines, ozone generators and the like. The solid state corona discharger has paired strip-shape ac electrodes which are arranged side by side nearly in parallel and spaced away from each other not to initiate discharge, a dielectric member layer which covers at least one side of the external surfaces enveloping both electrodes, and a thin dc-applied electrode which is in contact with one side of external surface of said dielectric layer and makes up a closed circuit loop of capacitances together with said ac electrodes (not connected in terms of direct current), as well as characterized by producing corona discharge between said ac electrodes and a dc-applied electrode with an ac power supply applied across said ac electrodes. In using the solid state corona discharger according to said configuration as a charger for a thin substance to be charged, the substance is charged by placing a dc-applied electrode opposite to the surface of the substance; connecting a dc power source between the dc-applied electrode and the surface to be charged; and generating a dc electric field between the solid state corona discharger and said surface to be charged; as well as by initiating corona discharge between an ac electrode and a dc-applied electrode.

Solid state corona discharger

An electrophotographic color image forming process wherein three light beams each representing image information of one of three primary colors or yellow, magenta and cyan of a color document to be recorded obtained by color separation are projected against an electrophotographic photosensitive member to form electrostatic latent images which are developed by toners of the three different colors, respectively, and printed by transfer-printing, to record a color image. The image information of three colors is simultaneously written to a surface of the photosensitive member as three scanning lines either by successively writing a plurality of sets of three scanning lines each representing image information of one color or by writing image information of different colors of the same set separately in three different zones, so that the scanning lines representing image information of different colors form a repeating series of three stripes of different colors. The electrostatic latent images formed on the scanning lines are excited in positions immediately before developing sections of respective colors and developed by the toners of respective colors to produce toner images of different color which are printed by transfer-printing on a transfer-printing sheet.

Color image forming method

A pressure sensitive adhesive toner for use in electrostatic photography which consists essentially of porous aggregates. Each aggregate consists essentially of a cluster of a multiplicity of individual granules of pressure sensitive adhesive substance, each granule being encapsulated by a coating film of a film-forming material. Particles of an inorganic or organic pigment and/or a magnetic substance are contained within the aggregate in the interstices between the granules and deposited on the surfaces of the encapsulated granules. The toner aggregates are free from a tendency to cohere, cake and agglomerate to each other. The toner can be readily pressure fixed, using a low impression pressure, onto a surface bearing an electrostatic latent image without causing any contamination thereon, thereby forming a distinct visible image.

Pressure sensitive adhesive toner of clustered encapsulated porous

In controlling the operation of an electrostatic apparatus to produce a large number of copies from an electrostatic image in a multiple copy process there is utilized a toner substance comprising a magnetic carrier composition in which each particle of the composition comprises a ferromagnetic material and a resin, the effective conductivity of the composition being determined by testing means separate from the electrostatic apparatus such that the effective conductivity is measured while the composition is free of absorbed water vapor and other gases encountered under operating conditions with the electrostatic apparatus.

Toner composition for multiple copy electrostatic photography

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Sagamihara, Japan

Itsuo Ikeda