US 5,319,422 AGranted

Liquid electrophotographic developing device and method thereof

AssigneeFuji Photo Film Co., Ltd.

InventorsChikashi Ohishi, Chiaki Kawamoto, Hidefumi Sera, Sho Nakao

Life of this patent

Estimating the term…

Loading patent…

Abstract

A liquid electrophotographic developing device for developing a charged and exposed photoconductive material which includes a photoconductive layer formed on one surface of a conductive layer. The liquid electrophotographic developing device is comprised of developing section, a developing solution tank provided in a housing and filled with a developing solution, conveying rollers for conveying the photoconductive materials, a developing electrode and a back electrode which are disposed parallel along a conveying path of the photoconductive material in the developing section, and a developing solution supplying device disposed above the developing electrode. The developing electrode is spaced part from the photoconductive layer, and the back electrode is disposed to come into contact with the back surface of the photoconductive material. Upon directly connecting the electrodes, toner particles contained in the developing solution adhere to the photoconductive layer to achieve development. The developing electrode does not touch the photoconductive layer to make a developed image free from soiling. The housing is covered with a lid to prevent the vaporizing of the developing solution. The developing solution is circulated through the developing section by a circulating device.

Claims17

Dependent claims

A liquid electrophotographic developing device for developing a photoconductive material and which is made of a conductive base material with a photoconductive layer formed thereon by the use of a liquid toner functioning as a developing solution, comprising

a developing section having a lower housing and a lid mounted on the lower housing, and an entrance portion and an exit portion;
means for conveying the photoconductive material along a conveying path of the photoconductive material from the entrance portion to the exit portion of the developing section;
a developing electrode having a first end and a second end, and being disposed parallel to and above the conveying path between the conveying means and in confronting relation to a photoconductive surface of the photoconductive material;
a back electrode having a first end and a second end, disposed parallel to and below the conveying path between the conveying means so as to contact the back surface of the photoconductive material, the developing electrode and the back electrode being connected respectively to an electric source;
means for supplying the liquid toner to the photoconductive surface of the photoconductive material at the vicinity of the first end of the developing electrode;
means for circulating the liquid toner, said circulating means including a liquid toner tank, and a pump disposed in the liquid toner tank and being connected to the liquid toner supplying means, the liquid toner supplied to the photoconductive surface of the photoconductive material being collected in the liquid toner tank and being circulated through the liquid toner supplying means for developing the photoconductive mater;
means for preventing the liquid toner from vaporizing in cooperation with the lid;
and
a first guide plate provided at the entrance portion of the lower housing and a second guide plate provided in the exit portion of the lower housing for guiding the photoconductive material along the conveying path, said first and second guide plates extending externally of said lower housing and comprising a portion of said vaporizing preventing means.

6 more elements

a developing section having a lower housing and a lid mounted on the lower housing, and an entrance portion and an exit portion;
means for conveying the photoconductive material along a conveying path of the photoconductive material from the entrance portion to the exit portion of the developing section;
a developing electrode having a first end and a second end, and being disposed parallel to and above the conveying path between the conveying means and in confronting relation to a photoconductive surface of the photoconductive material;
a back electrode having a first end and a second end, disposed parallel to and below the conveying path between the conveying means so as to contact the back surface of the photoconductive material, the developing electrode and the back electrode being connected respectively to an electric source;
means for supplying the liquid toner to the photoconductive surface of the photoconductive material at the vicinity of the first end of the developing electrode;
means for circulating the liquid toner, said circulating means including a liquid toner tank, and a pump disposed in the liquid toner tank and being connected to the liquid toner supplying means, the liquid toner supplied to the photoconductive surface of the photoconductive material being collected in the liquid toner tank and being circulated through the liquid toner supplying means for developing the photoconductive mater;
means for preventing the liquid toner from vaporizing in cooperation with the lid;
and
a guide plate provided at the exit portion, extending outwardly from said lower housing along the conveying path, and a shutter pivotably provided adjacent said exit portion and being opposed to the guide plate to pivotally move in directions of approaching and moving away from the guide plate and being opposed to the guide plate so as to substantially tightly seal the developing section to prevent the liquid toner stored therein from coming in contact with the external air.

6 more elements

Dependencies are inferred from the claim text.