Minolta Camera Kabushiki Kaisha

Minolta Company, Ltd.

Toeisangyo Co., Ltd.

Shuji Iino

Izumi Osawa

Hideo Hotomi

Isao Doi

Mitsutoshi Nakamura

Toshimitsu Fujiwara

Akihito Ikegawa

Kenji Masaki

Hidetoshi Miyamoto

Masaki Asano

Seishi Ojima

Masaharu Kanazawa

Masanori Fujiwara

Takaji Kurita

Yukio Tanigami

Kenzo Tanaka

Hiroshi Mizuno

Masami Yamada

Ken Matsubara

Eiichi Sano

Hirohisa Kitano

Noriko Yoshida

Hotomi Hideo

(1) Electrophotographic liquid developer comprising electrically insulating medium liquid and toner dispersed in the medium liquid, wherein the toner has a melt viscosity (.eta.) in a range from 2.times.10.sup.2 poises to 1.times.10.sup.5 poises at 100.degree. C. in a dry state, and has a glass transition temperature of 20.degree. C. or more. (2) Electrophotographic liquid developer comprising electrically insulating medium liquid and toner dispersed in the medium liquid, wherein the toner contains binder resin exhibiting at least one peak in each of ranges of a molecular weight lower than 5000 and of a molecular weight of 5000 or more when detected by a gel permeation chromatography (GPC). (3) An image forming apparatus comprising an electrostatic latent image carrier for forming an electrostatic latent image; a liquid developing device developing the electrostatic latent image formed on the electrostatic latent image carrier into a visible toner image with liquid developer; an intermediate transfer member carrying the toner image transferred thereto from the electrostatic latent image carrier for further transferring the transferred toner image to a record member; and a heating device for heating the intermediate transfer member, wherein the liquid developing device develops the electrostatic latent image with the liquid developer of the above (1) or (2).

Electrophotographic liquid developer and image forming apparatus

A liquid developer having a superior sedimentation characteristic and floating characteristic and an image forming apparatus using said liquid developer, wherein said liquid developer comprising toner dispersed in liquid medium and the difference in specific gravity between said toner and said liquid medium is at or lower than a prescribed level.

Liquid developer and image forming apparatus

A liquid developer having polymer particles dispersed in a dispersion medium, wherein the polymer particles have a mean volume particle size d.sub.50 of 0.5.about.5.0 .mu.m, and degree of flatness (longest diameter of a single particle/shortest diameter of a single particle) is greater than 1.5 but less than 30.

Liquid developer having polymer particles of a flat configuration

A color image forming method and apparatus of the electrophotographic type with a plurality of liquid developing devices. In a plurality of liquid developing devices accommodating liquid developer comprising colored microparticles dispersed in an electrically insulated fluid medium are used to form toner images of different colors, which are electrostatically transferred and overlaid one over another on a transfer medium to produce an overlaid toner image. The color image forming method and apparatus providing excellent overlay transfer characteristics for toner images transferred to a transfer medium.

Color image forming method and apparatus providing for efficient toner

The present invention provides a liquid developer for electrophotography comprising: carrier liquid, and toner particles, dispersed in the carrier liquid, formed of binder resin and colorant, wherein said carrier liquid contains acidic dispersion resin and basic dispersion resin which are soluble in said carrier liquid. Further, the present invention provides a liquid developer for electrophotography comprising: carrier liquid, and toner particles, dispersed in the carrier liquid, formed of binder resin and colorant, wherein said liquid developer contains a basic dispersion resin that is soluble in said carrier liquid and has a moisture content of 500.about.20,000 ppm, and has an acidic group on the surface of the toner particle.

Liquid developer

A liquid developer transfer device disposed between a reservoir accommodating a liquid developer having a fluid medium and electrically charged toner particles dispersed therein and an electrostatic latent image carrying member, which performs toner transfer by repeating electrodeposition.

Liquid developer transporting device and liquid developing device

A method for producing a liquid developer comprising steps of:

Toner and liquid developer, liquid developer, and method of producing

An intermediate transfer member for use in image forming apparatus which produce images by transferring a toner image formed on an image-bearing member to an intermediate transfer member, and transferring the toner image held on said intermediate transfer member to a recording medium. The intermediate transfer member comprises at least three layers of a conductive substrate, intermediate layer, and surface layer, and the volume resistivity of said surface layer is lower than the volume resistivity of said intermediate layer.

Intermediate transfer member for image forming apparatus

This invention relates to a liquid developer monitoring device comprising a first electrode which contacts with a liquid developer comprising a liquid medium and electrically charged toner particles dispersed therein, a second electrode being either a developing roller or a separate roller which provides a fresh surface and immerses said surface in the liquid developer, an electric power source which applies a bias voltage between said first and second electrodes so as to deposit the toner particles on the second electrode, and a sensor which measures magnitude of current flowing between said first and second electrodes during the deposition of the toner particles. A cleaning device removes the deposited toner on the second electrode. The sensor includes an electric coil, a magnet inserted in the coil and a Hall element.

Liquid developer monitoring device, liquid developer controlling system,

A liquid developer for developing an electrostatic latent image having a carrier fluid and electrically charged toner particles dispersed therein, wherein the liquid developer satisfies the following relationship:

Liquid developer and developing method and developing apparatus using

An image forming apparatus including an device for developing an electrostatic latent image formed on a latent image carrying member using a liquid developer containing toner particles dispersed in a fluid medium, and an intermediate transfer member having a surface layer onto which is transferred the developer image from the image carrying member, water absorption of the surface layer being in the range between 0.15 and 10.0 percent by weight.

Image forming apparatus using an intermediate transfer member, an

Liquid developing method and liquid developing device for developing an electrostatic latent image formed on a latent image carrying member via a toner dispersed in a carrier liquid. An electrostatic latent image is formed on an image carrying surface, a liquid developer layer having a bottom layer of toner particles as the main constituent and a top layer of liquid carrier as the main constituent is formed on a developer holding surface and the electrostatic image is contacted with the top layer without substantially contacting the bottom layer with the image carrying surface. A member for maintaining a clearance between an image carrying member and a developer holding member at a predetermined space in which the top layer contacts with the electrostatic latent image without contacting the bottom layer to the image carrying member is provided.

Method and device for developing with a liquid

A charging device including a charging member which is in contact with or minutely spaced from a surface of a photosensitive member, device for applying a constant voltage to the charging member, and a controller for controlling the voltage applied to the charging member when a current flowing from the charging member to the surface of the photosensitive member exceeds a predetermined value.

Charging device for charging the surface of a photosensitive member in

A liquid-type developing device for use in an image forming apparatus such as a copying machine or printer, that develops an electrostatic latent image formed on a latent image holding member using a liquid-type developer. In the liquid-type developing device, a developer carrying member supplies the liquid-type developer to the surface of the electrostatic latent image carrier at a developing region, and a removing member removes residual liquid-type developer remained on the surface of the developer carrying member after development. Before removing the residual liquid-type developer remained by the removing member, a fluid supplying member supplies a fluid on the surface of the developer carrying member so that the removing member removes said residual liquid-type developer with said fluid.

Liquid-type developing device

A charging device and method in which a charging member, for example, of a brush, plate, film or roller type, for charging a charge-receiving member is disposed at a predetermined distance from the charge-receiving member. The distance is adjusted at not greater than a discharge start distance when the discharge is started and is adjusted at greater than the discharge start distance and less than a discharge stop distance after the discharge is started. The discharge start distance is the distance at the start of discharge when two electrodes are in close proximity as a voltage is applied, and the discharge stop distance is the distance directly before a stable discharge stops when two electrodes are separated while in state of discharge.

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Hirakata, Japan

Shuji Iino