Ishihara Sangyo Kaisha, Ltd.

Other

Dainippon Screen Mfg. Co., Ltd.

Sadao Murasawa

Hajime Murakami

Mitsuru Watanabe

Akira Fujishima

Kazuhito Hashimoto

Yasuro Fukui

Masatsuyo Maruo

Kei Takahata

Hiroshi Ichida

Shoji Komatsubara

Yukio Hatabe

Hitoshi Ando

Mizuho Okada

Yoshio Hirobe

Nobuharu Oka

Takao Nakayama

Tooru Horikawa

A photocatalyst composite is provided which comprise a substrate having particles of a photocatalyst such as titanium oxide, adhered thereon via a less degradative adhesive such as a fluorinated polymer comprising a copolymer of a vinyl ester and/or vinyl ether and a fluoroolefin, or a silicon based polymer or cement. Furthermore, a process for producing the photocatalyst composite and a coating composition containing the photocatalyst composite are provided.

Photocatalyst composite and process for producing the same

An electrophotographic photosensitive element for use in offset printing masters comprises an electrically conductive support having an photosensitive layer formed thereon where said layer comprises titanium dioxide and zinc oxide in a specific amount of zinc oxide based on the total amount of titanium dioxide and zinc oxide and a method for manufacturing the masters from the elments by subjecting the same to charging, exposure, development and lipophobicating treatment.

Electrophotographic photosensitive element and a process for

The present invention provides novel titanium dioxide aggregates especially suitable for an electrophotographic photosensitive material. This titanium dioxide aggregates comprise sintered aggregates of fine primary particles and have a rutile type crystal structure and an oil absorption of 35-65. This titanium dioxide aggregates which are treated with a mineral acid is also provided. There is also provided an electrophotograpic photosensitive material which contains such titanium dioxide in a photosensitive layer.

Titanium dioxide aggregates process for producing same and

Disclosed is an electrophotographic photoreceptor which is superior in sensitivity to light of longer wavelength region with good stability of the sensitivity and is suitable for formation of high quality color image by scanning exposure with laser beam. This photoreceptor comprises an electroconductive support and, provided thereon, a photosensitive layer containing a titanium dioxide sensitive to light of longer wavelengths which is obtained by treating the surface of titanium dioxide particles with a mineral acid and then supporting on the surface of the particles a cyanine dye sensitizer and a hydrophobic organic compound. The mineral acid is preferably hydrofluoric acid and the hydrophobic organic compound is preferably aromatic or aliphatic organic acid and acid anhydride thereof.

Electrophotographic photoreceptor containing titanium dioxide

An apparatus for producing an electrophotographic print on a photosensitive receptor which is movable through a plurality of predetermined stations so as to produce an electrostatic latent image on the photosensitive receptor, the apparatus including a rotary drum having a peripheral surface which defines an image forming section and a non-image forming section, the photosensitive sheet being placeable on the image forming section of the drum surface, a developing unit having at least one developing section for supplying a developer to the photosensitive sheet on the drum, thereby making the electrostatic latent image visible, and a device for collecting the used developer from the photosensitive sheet, the collecting device being provided axially of the drum in the non-image forming section of the peripheral surface.

Apparatus for producing an electrophotographic print

This invention is a method of color electrophotography in which toner images are superposed sequentially on a photosensitive material sheet to form a multi-color image by using a liquid developer. According to this method, the photosensitive material sheet is made to pass by a conductive doctor member and then by an air blasting member in sequence immediately after development, so as to form the multi-color image. By this method, the multi-color image can be formed in the condition that most of a excess developer is removed while a small quantity of carrier liquid containing no residual toner particles is made to exist as a uniform liquid layer on the surface of the photosensitive material sheet, and thus a clear image free from a fogging of the surface can be obtained.

Method of color electrophotography

In practicing multi-step reproduction of color image by electrophotography using an electrophotographic photosensitive material prepared by overlaying a photosensitive layer composed mainly of titanium dioxide and a binder on an electroconductive substrate, exposure to an optical image is first carried out, then positive corona charging is carried out to form a positive electrostatic latent image and subsequently developing is carried out. Further, prior to the exposure to an optical image, negative corona charging and/or AC corona charging are additionally carried out. By this electrophotographic process effectively utilizing the photomemory effect of titanium dioxide, multi-color images can be produced, and an image having good contrast can be reproduced easily and stably.

Multicolor electrophotographic process using TiO.sub.2

This invention relates to a liquid developer for use in color electrophotography for obtaining a photographic image by subjecting an electrostatic latent image to liquid development, and more particularly it relates to such a liquid developer for electrophotography comprising a coloring agent, a binder and an electrically insulating liquid, the particles of said coloring agent having coated or distributed thereon aluminum or zinc hydroxide.

Liquid developer for color electrophotography

A liquid developing apparatus for developing a latent electrostatic image by contacting a liquid developer with an electrophotographic photoreceptor bearing said latent electrostatic image on the undersurface thereof while moving the electrophotographic photoreceptor horizontally over a liquid developing bath. In the apparatus, a number of horizontally spaced developing electrodes in the form of bars having a vertical cross-section in the shape of a tetragon are disposed in the bath very near the undersurface of the photoreceptor. When the liquid developing apparatus is used, an electrophotographic image can be obtained having a high quality but being free from non-uniformity of image density, edge effect and flow of image or streaks.

Liquid developing apparatus

A liquid developer for subjecting an electrostatic latent image to wet development to obtain a copied image, which contains as a charge controlling agent a reaction product or mixture of zirconium (tetravalent) alkoxide or vanadyl (trivalent) alkoxide and an organic compound containing hydroxyl group, carboxyl group or carbon-carbon double bond in its molecule can reproduce an original clearly and exactly.

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Kusatsu, Japan

Sadao Murasawa