Pfu Limited

Eri Yamanishi

Shigeharu Okano

Hironaga Hongawa

Isao Nagata

Satoshi Sakai

Yutaka Nakashima

Akihiko Inamoto

Norihiro Yamasaku

Tadashi Nishikawa

Masanobu Hongo

Motoharu Ichida

Satoshi Miyamoto

Seiichi Takeda

Jiyun Du

Shigeki Uesugi

Yasuhiko Kishimoto

Tatsuo Nozaki

Yoshiro Kawamoto

Tadasuke Yoshida

Yoshiaki Fujimoto

Satoshi Moriguchi

A full-color electrophotographic apparatus of the present invention is configured such that a toner image is formed on an intermediate transfer member. The intermediate transfer member is heated to a temperature equal to or higher than the softening start temperature of resin contained in a liquid toner and equal to or lower than the withstand temperature of a photoconductor member. A carrier-removing roller to which bias can be applied abuts the intermediate transfer member so as to remove a carrier while packing softened toner by the force of an electric field induced by bias. In a transfer section for transfer to a printing medium, a backup roller presses the printing medium against the intermediate transfer member, and the toner image is transferred from the intermediate transfer member to the printing medium. Before being pressed against the toner image on the intermediate transfer member, the printing medium is heated. Bias is applied to the backup roller such that the toner image on the intermediate transfer is attracted toward the printing medium by the action of an electric field, thereby assisting transfer. By so doing, the intermediate transfer member does not need to undergo cooling before coming into contact with the photoconductor member, thereby avoiding occurrence of thermal damage to the photoconductor member.

Full-color electrophotographic apparatus using liquid toner containing resin

A cleaning apparatus for a liquid-development electrophotographic apparatus in which, after a toner image formed on a surface of an intermediate transfer member by use of a liquid developer is transferred to a printing medium, the liquid developer remaining on the intermediate transfer is removed and collected. The cleaning apparatus includes a cleaning-liquid application device for applying a cleaning liquid to the intermediate transfer member which has transferred an image to the printing medium; a bias voltage application device for applying a bias voltage opposite in polarity to charged toner particles of the developer to the intermediate transfer member; and a collection device for removing the cleaning liquid which has been applied to and the residual developer which remains on the intermediate transfer member from the intermediate transfer member without transfer of an image to the printing medium, and collecting the removed cleaning liquid and residual developer.

Method and device for cleaning liquid development electrophotographic device

A liquid-development electrophotographic apparatus forms on a toner-image-bearing body a plurality of color images developed by a plurality of developing units, one for each color, that use liquid toner. One or more carrier-removing units for removing excessive carrier from a toner layer that forms a toner image are disposed downstream of each developing unit and upstream of the next developing unit disposed upstream of the former developing unit with respect to a process progress direction. Each carrier-removing unit includes two or more conductive collection rollers to which a bias voltage is applied in such a direction as to press toner against the toner-image-bearing body and which is brought into contact with the toner-image-bearing body. The upstream roller is rotated in the same direction as the direction of surface movement of the toner-image-bearing body, whereas the downstream roller is rotated in the opposite direction. The result is that influence of carrier on the already transferred image is suppressed, and hence occurrences of irregular transfer of the images and occurrences of disturbance of the already transferred image are minimized.

Liquid development electrophotographic device

In the present invention, a toner image produced through a development process of supplying a liquid toner onto an image bearing body bearing an electrostatic latent image is transferred from the image bearing body onto an intermediate transfer body and then transferred from the intermediate transfer body onto a printing medium by use of a backup roller in a transfer-and-fixation zone. The printing medium is preheated to a temperature required for transfer and fixation before the printing medium reaches the transfer-and-fixation zone. No heating means is provided in the transfer-and-fixation zone, and the intermediate transfer body and the backup roller are pressed against each other at a high pressure ranging from 10 kg/cm to 60 kg/cm . Alternatively, the intermediate transfer body is provided with heating means; resin for use in the liquid toner has a softening temperature not higher than withstand temperatures of members other than the intermediate transfer body such as a photosensitive drum; and the intermediate transfer body is heated to a temperature not lower than the softening temperature of the resin and not higher than the withstand temperatures of the other members.

Transfer-and-fixation system with preheated printing medium for creating images using liquid-development electrophotographic apparatus

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Hakui, Japan

Eri Yamanishi