Abstract: A developing device includes a container, a toner holding member, a developing electric field forming unit, a layer forming unit, an electrode member, and a low-frequency electric field forming unit. The container accommodates toner. The toner holding member holds toner and transports the toner to a developing region where the toner holding member and the latent image holding member face. The developing electric field forming unit forms a developing electric field for developing a latent image held on a latent image holding member. The layer forming unit forms a toner layer on the toner holding member prior to the developing region. The electrode member faces the toner holding member. The low-frequency electric field forming unit forms a low-frequency electric field acting on residual toner between the electrode member and the toner holding member, and forms stripe-shaped projections in accordance with a period of the low-frequency electric field.

Abstract: A developing device includes a container, a toner holding member, a developing electric field forming unit, a layer forming unit, an electrode member, and a low-frequency electric field forming unit. The container accommodates toner. The toner holding member holds toner and transports the toner to a developing region where the toner holding member and the latent image holding member face. The developing electric field forming unit forms a developing electric field for developing a latent image held on a latent image holding member. The layer forming unit forms a toner layer on the toner holding member prior to the developing region. The electrode member faces the toner holding member. The low-frequency electric field forming unit forms a low-frequency electric field acting on residual toner between the electrode member and the toner holding member, and forms stripe-shaped projections in accordance with a period of the low-frequency electric field.

Abstract: A developer containing device includes: a developer container having an opening through which developer can be filled in; a closing member that is removably installed to the developer container to close the opening; a stirring and feeding member that is rotatably supported in the closing member and stirs and feeds the developer contained in the developer container by rotating in one direction; and a fitting part that fixes the closing member to the developer container by rotating the closing member in the same direction as the rotational direction of the stirring and feeding member.

Abstract: The toner cartridge is provided with: a toner storing container of a rectangular shape having a toner feeding opening in an angular portion of the toner storing container; a stirring conveying member that is disposed so as to rotate in a predetermined rotation direction in the toner storing container and stirs and conveys toner in the toner storing container toward the toner feeding opening; a waste toner storing container that stores reclaimed toner; and a partition member that is held by the toner storing container, partitions between the toner storing container and the waste toner storing containers and has a bearing portion axially supporting a rotating shaft of the stirring conveying member and extending into inside of the waste toner storing container. The toner stored in the toner storing container has an average value of a shape factor (SF1) of about 130 or less.

Abstract: The toner cartridge is provided with: a toner storing container of a rectangular shape having a toner feeding opening in an angular portion thereof; and a stirring conveying member that is rotatably disposed inside the toner storing container in a predetermined rotation direction and that stirs and conveys toner toward the toner feeding opening in the toner storing container. Compression ratio defined by the following equation (1) of the toner stored in the toner storing container is 0.25 to 0.38. Compression ratio=(P?A)/P ??(1) (Provided that in the equation (1), P represents a packed bulk density of toner and A represents an aerated bulk density of toner.

Abstract: A developer containing device includes: a developer container having an opening through which developer can be filled in; a closing member that is removably installed to the developer container to close the opening; a stirring and feeding member that is rotatably supported in the closing member and stirs and feeds the developer contained in the developer container by rotating in one direction; and a fitting part that fixes the closing member to the developer container by rotating the closing member in the same direction as the rotational direction of the stirring and feeding member.

Abstract: The toner cartridge is provided with: a toner storing container of a rectangular shape having a toner feeding opening in an angular portion thereof; and a stirring conveying member that is rotatably disposed inside the toner storing container in a predetermined rotation direction and that stirs and conveys toner toward the toner feeding opening in the toner storing container. Compression ratio defined by the following equation (1) of the toner stored in the toner storing container is 0.25 to 0.38. Compression ratio=(P?A)/P ??(1) (Provided that in the equation (1), P represents a packed bulk density of toner and A represents an aerated bulk density of toner.

Abstract: The toner cartridge is provided with: a toner storing container of a rectangular shape having a toner feeding opening in an angular portion of the toner storing container; a stirring conveying member that is disposed so as to rotate in a predetermined rotation direction in the toner storing container and stirs and conveys toner in the toner storing container toward the toner feeding opening; a waste toner storing container that stores reclaimed toner; and a partition member that is held by the toner storing container, partitions between the toner storing container and the waste toner storing containers and has a bearing portion axially supporting a rotating shaft of the stirring conveying member and extending into inside of the waste toner storing container. The toner stored in the toner storing container has an average value of a shape factor (SF1) of about 130 or less.

Abstract: An optical printer head with a plurality of light-emitting devices arranged in two dimensions is capable of providing a desired amount of exposure using light-emitting devices having even small luminance, ease of corrections to a sensitivity of a photosensitive body and to a positional displacement of an object to be printed, performing printing on multiple gray scales and implementing high density and miniaturization. The optical printer head is so configured that a picture element array including picture elements containing light-emitting devices arranged in line and string directions in two dimensions, a horizontal scanning circuit to feed data signals to each picture element string in the picture element array and a vertical scanning circuit to sequentially select and activate each picture element in the picture element array are formed on a same insulating substrate to support production of the above effects.

Abstract: A liquid electrophotographic developing apparatus capable of preventing image drift and reducing the load in the squeezing process. A developing roller faces a photoreceptor belt with a predetermined spacing to supply a liquid developer to the photoreceptor belt while rotating at a peripheral velocity in the opposite direction to that of the photoreceptor belt in a developing region thereon. A peripheral velocity ratio of the peripheral velocity to a moving velocity of the photoreceptor belt is determined so as to maximize a solid component ratio of a developed toner layer on the photoreceptor belt.

Abstract: An image forming apparatus of the present invention includes a particle conveying body made up of a light-transmitting conductive layer, an insulative'screen provided on the conductive layer and formed with a number of pores, and a screen electrode formed on the screen. Photoconductive, colored particles are charged to negative polarity and then caused to fill the pores by an electric field. When the particles in the pores are exposed via the conductive layer, electron-hole pairs are generated in the particles. An electric field of as high as 104 V/cm or above is formed between the conductive layer and the screen electrode and separates the electrons and holes. The electrons leak to the conductive layer and cause the particles to be charged to positive polarity. An electric field formed between a facing electrode positioned behind a recording medium and the conductive layer causes the particles to fly toward and deposit on the medium.

Abstract: In a wet-type developing apparatus in which a latent image carrying member and a squeeze roller are moved in the opposite directions to each other while they are not brought into contact with each other at the closest position thereof, a liquid toner layer on the latent image carrying member which is smaller in thickness than the gap interval between the latent image carrying member and the squeeze roller is made to invade into the gap, and the liquid toner invading into the gap between the squeeze roller and the latent image carrying member are brought into contact with the squeeze roller by electrical attractive force based on electric field formed between the squeeze roller and the latent image carrying member, thereby forming meniscus.

Abstract: A porous photosensitive body is provided which is excellent for mass production and lower in production costs and is capable of obtaining a good degree of image-formation and of increasing its productivity and reliability. The porous photosensitive body is provided with a drum used for forming a photosensitive body constructed by stacking, in order, an insulating layer, a photo-conductive layer and a translucent conductive layer on an inner circumferential face of a surface electrode which is composed, of a metal jointless cylinder drum having a large number of fine holes which are aligned at equal intervals both in a circumferential direction and in a direction of an axial line of the cylindrical drum and are opened on inner and outer circumferential faces of the metal jointless cylinder and wherein the insulating layer is provided with a through hole communicating with each of the fine holes.

Abstract: A drive roller is rotated and a high voltage periodically alternating between plus and minus based on the potential of a conductive portion of the drive roller 2 is applied by a high voltage power source 4 to an electric charger, so that the surface of the drive roller 2 is charged plus and minus alternately. Since the drive roller 2 is charged, a sleeve 1 is absorbed to and held by the drive roller 2 so as to be rotated and fed together with the drive roller. Moreover, the sleeve 1 is separated from the drive roller 2 by a separator so as to obtain a sag. When the drive roller rotates further, the sleeve 1 is again absorbed to and held by the drive roller 2 charged periodically plus and minus, so as to be rotated together with the drive roller. Thus, the present invention eliminates scratches which may be caused by friction on a developing roller or on a photosensitive body surface and also eliminates contamination with oil.

Abstract: A liquid electrophotographic developing apparatus capable of preventing image drift and reducing the load in the squeezing process is disclosed. A developing roller faces a photoreceptor belt with a predetermined spacing to supply a liquid developer to the photoreceptor belt while rotating at a peripheral velocity in the opposite direction to that of the photoreceptor belt in a developing region thereon. A peripheral velocity ratio of the peripheral velocity to a moving velocity of the photoreceptor belt is determined so as to maximize a solid component ratio of a developed toner layer on the photoreceptor belt.

Abstract: An image forming apparatus of the present invention includes a particle conveying body made up of a light-transmitting conductive layer, an insulative screen provided on the conductive layer and formed with a number of pores, and a screen electrode formed on the screen. Photoconductive, colored particles are charged to negative polarity and then caused to fill the pores by an electric field. When the particles in the pores are exposed via the conductive layer, electron-hole pairs are generated in the particles. An electric field of as high as 104 V/cm or above is formed between the conductive layer and the screen electrode and separates the electrons and holes. The electrons leak to the conductive layer and cause the particles to be charged to positive polarity. An electric field formed between a facing electrode positioned behind a recording medium and the conductive layer causes the particles to fly toward and deposit on the medium.

Abstract: In a wet-type developing apparatus in which a latent image carrying member and a squeeze roller are moved in the opposite directions to each other while they are not brought into contact with each other at the closest position thereof, a liquid toner layer on the latent image carrying member which is smaller in thickness than the gap interval between the latent image carrying member and the squeeze roller is made to invade into the gap, and the liquid toner invading into the gap between the squeeze roller and the latent image carrying member are brought into contact with the squeeze roller by electrical attractive force based on electric field formed between the squeeze roller and the latent image carrying member, thereby forming meniscus.

Abstract: A porous photosensitive unit has a transparent conductive layer formed on a surface of a transparent substrate. A photoconductive layer is formed on a surface of the transparent conductive layer. A porous insulating layer formed on a surface of the photoconductive layer has a plurality of holes for holding conductive color particles. The plurality of holes includes a first hole and the adjacent second and third holes. An upper or screen electrode is formed on a surface of the porous insulating layer except where the holes are formed. The photosensitive unit includes an optical arrangement in which, when a light source emits light to cause conductive color particles to fly out of the first hole only, the light exposes a region, within the photoconductive layer, which substantially coextends with a surface portion of the photoconductive layer that is exposed by the first hole.

Abstract: An image recording apparatus and an image recording method enable high density and without blank space between pixels printed on a recording medium to be printed. The image recording apparatus comprises a multi-hole photoreceptor provided with a transparent conductive layer, photoconductive layer, and multi-hole layer having a plurality of holes arranged with equal interval, on a transparent supporting structure, and an opposite electrode arranged so as to be opposite to the multi-hole photoreceptor with interval while inserting a recording medium. Conductive colored particles which fly in order from a plurality of holes of the multi-hole photoreceptor form respective pixels by driving the multi-hole photoreceptor corresponding to the pixel.

Abstract: Disclosed herein is a photoreceptor for electrophotography having an over coating layer formed on a substrate and prepared by applying a composition containing silica particles, an organic compound chemically bonded thereto and a photo polymerization initiator and by curing said composition; said organic compound having an polymerizable unsaturated group, a group designated by Formula (1) or a group designated by Formula (2), and said silica particles and said organic compound being bonded with each other through a silyloxy group. The photoreceptor for electrophotography has not only excellent durabilities and an excellent resistance to printing but also excellent electrophoto characteristics such as sensitivity and a residual potential. ##STR1## (wherein --X-- is selected from --NH--, --O-- and --S--, --Y-- is an oxygen atom or a sulfur atom, and when --X-- is --O--, Y is said sulfur atom).