Matsushita Electric Industrial Co., Ltd.

Hodogaya Chemical Co., Ltd.

Yuji Takashima

Hajime Yamamoto

Eisuke Ishida

Hisanori Nishiguchi

Masahiko Nakamura

Keiichi Yubakami

Yoshihide Miyazawa

Soichiro Mima

Hiroshi Onishi

Kenichi Nakano

Yukimasa Kuramoto

Katsuichi Motohashi

Koji Ikeda

Ryoichi Takayama

Hiromu Matsuda

Osamu Kawasaki

Masayoshi Miura

Wataru Shimotsuma

Eiichiro Tanaka

Michihiro Gonda

Takahiko Nankou

Kimiaki Yoshino

Fujio Oda

Hidenori Kunishige

Shigeru Tsubusaki

Kazunori Kitagaki

Hiroshi Onhisi

Shigeru Endo

An ink jet recording apparatus is disclosed, which apparatus has a pressure chamber that holds an ink liquid, and a nozzle communicating with the pressure chamber for discharging the ink liquid when pressure is applied to the pressure chamber. The pressure chamber has a diaphragm disposed therein. A piezoelectric element made of a monocrystalline or polycrystalline piezoelectric member highly oriented along a polarization axis showing perovskite structure, and mainly composed of lead zirconate titanate or barium titanate, is used to vibrate the diaphragm. When a specified voltage is applied to the piezoelectric element, it causes the ink liquid in the pressure chamber to be discharged into a recording medium at the front side of the nozzle.

Ink jet recording apparatus including a pressure chamber and pressure applying means

An electrophotographic color image forming method whereby black, yellow, magenta and cyan toner images are superimposed on a photoconductor (54) to transfer to paper, exposure being changed between black and color in a method in which development of black is performed by a contact developing method, and development of color by a direct current electric field projection developing method. Also, in exposure for color, the exposure amount is adjusted between highlight and shadow areas. A full color image of high saturation with good balance between black and color components is reproduced by changing the exposure amount between black and color. It is also possible to obtain a color image with good reproducibility of highlight areas as well as shadow areas.

Electrophotographic image forming method

An ink jet recording method utilizes an inking medium containing a liquid electrolyte. A chamber is provided for accommodating the liquid inking medium and having a pair of electrodes disposed therein. A signal generator is provided for applying to the pair of electrodes an electrolyzing signal for electrolyzing at least a portion of the electrolyte contained in the inking medium, and a subsequent discharge signal for effecting a discharge explosion of gases produced as a result of the electrolyzing signal. The inking medium is discharged from the chamber in response to the discharge explosion pressure resulting from the application of the electrolyzing and discharge signals.

Ink jet recording method utilizing electrolysis to effect ink discharge

Color electrophotographic method and apparatus

An ink jet recording apparatus includes an inking medium containing a liquid electrolyte. A chamber is provided for accommodating the liquid inking medium and having a pair of electrodes disposed therein. A signal generator is provided for applying to the pair of electrodes an electrolyzing signal for electrolyzing at least a portion of the electrolyte contained in the inking medium, and a subsequent discharge signal for effecting a discharge explosion of gases produced as a result of the electrolyzing signal. The inking medium is discharged from the chamber in response to the discharge explosion pressure resulting from the application of the electrolyzing and discharge signals.

Ink jet recording apparatus utilizing electrolysis to effects ink

A printing apparatus is disclosed. A toner image is formed on an image carrier. A solvent supply device supplies a solvent to the toner image in a direction toward such a side that the toner image makes contact with an image bearing medium, the solvent lowering the viscosity of the powder image. A transfer device presses the image bearing medium against the toner image of which viscosity is lowered by the solvent, thereby transferring the toner image to the image bearing medium.

Printing apparatus

A charging process, an exposure process, and a development process are performed to form a toner image on a photosensitive member for each of a plurality of different colors. The toner images for the respective colors form a composite color image. Second color toner image forming processes are effected subsequently to first color toner image forming processes. The first color charging process charges the photosensitive member to a first potential. The second color charging process charges the photosensitive member to a second potential. The second potential is set equal to or lower than the first potential. The composite color image is transferred to a sheet.

Method and apparatus for color electrophotography

A color electrographic apparatus is provided including a latent image forming device for forming plural electrostatic latent images respectively corresponding to image signals of different colors on the surface of a photoconductor, a plurality of toners of different colors each of which has the same polarity as the photoconductor, and a plurality of developing devices which are disposed in the vicinity of the photoconductor and each of which contain a colored toner for respectively developing the latest image without contact with the photoconductor under a direct electric field. A toner image is formed by a repeating cycle of making electric charges on the surface of the photoconductor, activating the latent image forming device so as to light expose an image corresponding to respective image signals of different colors on the surface of the photoconductor and activating a respective developing device so as to develop the exposed image by a respective toner corresponding to the image signal. Even further, a reversal flying preventing device is provided for preventing reversal flying of toner of the image from the photoconductor to one of the developing devices which is not developing as the image passes before the developing device.

Color electrophotographic apparatus and method

A cleaning device for use in a color electrophotographic apparatus in which a photosensitive medium is made to rotate for a plurality of times so as to conduct repetitional cycles each including charging, exposure and development, thereby forming toner images of different colors on the photosensitive medium. The cleaning device comprises a conductive fur brush for cleaning the surface of the photosensitive medium so as to remove any toner remaining on the surface of the photosensitive medium; and a driving mechanism for placing the fur brush in contact with the photosensitive medium during cleaning and for keeping the same away from the photosensitive medium when the cleaning is not conducted. The cleaning device effectively prevents any part of the toner after the transfer from remaining on the surface of the photosensitive medium.

Color electrophotographic apparatus and method of cleaning a

Disclosed is a color electrophotographic method of forming a plurality of images of different colors on a photosensitive medium by repetitions of a series of operations including steps for charging, exposure and development. An exposure of photosensitive medium is conducted to form an electrostatic latent image adjacent to a first toner image which has been formed in the previous process with a non-image are provided at the boundary of the first toner image. The difference in potentials between the toner image and the adjacent image is thereby eliminated, thus preventing scattering of toner particles. This results in a clear color print the colors of which are not blurred and of high purity.

In a color electrophotographic process wherein color toners are developed by toner flying under D.C. electric field, electrostatic capacitance of photoconductor (29, 30, 46, 65) is selected under 170 pF/cm.sup.2, so that undesirable discharging through the toner layer is prevented, and color contamination due to the discharging is prevented thereby providing clear color image printing.

Color electrophotographic method

Image forming method using electrically conductive, light transmissive

The disclosure is directed to light-transmitting image forming particles each containing at least a colorless subliming dye which develops color through reaction with a color developing agent, and also a coloring agent, and moreover, having at least a pair of parallel faces. When applied to a particular image forming process as disclosed, the particles can provide color images with an expanded latitude and a superior color purity, while, by bevelling or planing-off the edges defining the parallel faces, exposure amount may be reduced as compared with particles without such bevelling.

Image forming particles

An image forming process comprising steps of arranging on a support member, in accordance with image signals, image forming particles containing dye former which develops its color in reaction with a color developing agent, heat-transferring the dye former from the particles to an image receiving substrate. After the heat-transfer step, the color developing agent is caused to adhere to the dye former heat-transferred on the image receiving substrate to provide colored images. Choice of the image receiving substrate and the color developing agent is expanded. Fogging is not caused, color purity is not lowered, and the other image receiving material is not polluted due to reevaporation of the dye former which is on the image receiving substrate and is not reacted with color developing agent.

Growing community of inventors

Nishinomiya, Japan

Yuji Takashima