Mitsubishi Paper Mills Limited

Dainippon Screen Mfg. Co., Ltd.

Shigeyoshi Suzuki

Jun Yamada

Takao Senga

Yasuo Tsubai

Sadao Kuriu

Akira Furukawa

Eiji Kanada

Kazunaka Endo

Kyonosuke Yamamoto

Toshihito Maruyama

Koji Uchida

Akio Yoshida

Masahiko Saikawa

Shigeru Iguchi

Shin Nakagawa

Iwao Hirose

Tamotsu Iwata

Masahiro Yamasaki

Isamu Maruyama

Kenji Hirata

Masato Asano

Kunihiro Fukushima

Yoshitake Yoshihiro

Masayoshi Otsuka

Tokubee Maegawa

Kyonosuke Yammamoto

There is disclosed a method of processing a light-sensitive material which comprises exposing a light-sensitive material having at least one light-sensitive layer on a support, and subjecting to development by a dipping system or a coating system, and then, peeling at least the light-sensitive layer off by bringing a peeling material into close contact with the light-sensitive material, wherein the peeling material is a material having a liquid-absorbing rate in which a liquid-absorption amount within 0.1 second after getting in contact with a liquid is 60% or more based on a liquid-absorption amount within 0.2 second after the same.

Method of processing light-sensitive material

There are disclosed a processing apparatus for a photosensitive material having a coating device of a processing liquid to a photosensitive material, which comprises using a slot die having a manifold and a slot at the inside of the die as a coating device, and a processing apparatus for a photosensitive material which comprises a photosensitive material transferring device, a photosensitive material detecting device, a slot die for coating a processing liquid to the photosensitive material and having a manifold and a slot at the inside of the die, and a device for supplying a predetermined amount of the processing liquid to the slot die, wherein a detection result at the detecting device of the photosensitive material is fed back to the supplying device of the processing liquid to control operation of the processing liquid supplying device.

Apparatus for processing photosensitive material

This invention provides a method for making a lithographic printing plate of high resolving power and high printing endurance which comprises imagewise exposing a photoreceptor having a conductive layer and a printing sheet comprising a conductive support having thereon a dielectric non-photosensitive layer which are placed opposite to each other while applying a direct voltage between said conductive layer and said conductive support by a direct current source to form a positive electrostatic latent image on said non-photosensitive layer of the printing sheet and then subjecting the image to development and fixation.

Method for making lithographic printing plate

Disclosed is a panchromatic silver halide photographic emulsion for use in DTR process which exhibits a high sensitivity, especially to blue light, a high contrast and a high resolving power and a photographic element containing said silver halide emulsion layer. Said emulsion contains a blue-sensitizing dye represented by the general formula [I]: ##STR1## (wherein Z.sub.1, Z.sub.2, R.sub.1, R.sub.2, X.sub.1 and m are as defined before). Said emulsion may contain, as green- and red-sensitizing dyes, those represented by the general formula [II] and [III] to attain more effectively the objects: ##STR2## (wherein Z.sub.3, Z.sub.4, Z.sub.5, Z.sub.6, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, X.sub.2, X.sub.3 and m are as defined before). Said photographic element is an excellent ligtographic printing plate.

Panchromatic silver halide photographic element

Disclosed is a method for producing a resin dispersion type electrophotographic liquid developer containing resin particles dispersed in a high insulation hydrocarbon medium which comprises, in the presence of a first polymer dissolved in said medium which is soluble in said medium and has a polar functional group having adsorptivity to a second polymer, polymerizing a monomer having a polar functional group having adsorptivity to said first polymer to produce the second polymer which is low in solubility in said medium and is substantially particle.

Method for producing liquid developer for electrophotography

There is disclosed a method for exposing in two steps a photosensitive material to an original of a continuous tone image mingled with a line image through a lens of a process camera of the daylight type, which comprises feeding said photosensitive material to an exposure unit disposed in nearly vertical position in said camera and provided with a suction mechanism, and setting the sensitive material in place; (A) in case of the first step exposure being made to an original of a continuous tone image, (a) moving a contact screen from a position in front of the photosensitive material to establish a close contact with the photosensitive material and exposing the sensitive material imagewise to the continuous tone image, subsequently (b-1) moving the contact screen by the internal shift to the position in front of the sensitive material so that it is out of the exposure region while the sensitive material being remained as such, or (b-2) moving the contact screen internally to a position in front of the sensitive material and then shielding the latter against light in such a manner that the sensitive material can be released of the shield at the time of the second step exposure, the contact screen being absent at least in the exposure region at the time of second step exposure and subsequently (c) exposing the sensitive material to the line image (second step exposure), or (B) in case of the first step exposure being made to the line image, (a') exposing the sensitive material to the line image in the first step, then (b'-1) moving the contact screen, which is in front of the sensitive material and kept outside the exposure region, to establish close contact with the sensitive material while the sensitive material being remained as such, or (b'-2) shielding the sensitive material against light in such a manner that the sensitive material can be released of the shield at the time of bringing the contact screen into close contact with the sensitive material and moving the contact screen from a position in front of the sensitive material to establish a close contact with the photosensitive, and subsequently (c') exposing the sensitive material to the continuous tone image (second step exposure).

Method of exposing photosensitive material

Disclosed is a method for the direct making of printing plates for multicolor lithography capable of faithfully reproducing repeatedly continuous gradation multicolor original, which comprises using color separation filters for at least blue, green, and, red and repeating a sequence of the steps of shielding an exposure section against light by a light shielding means; feeding to said exposure section a magazine containing a sensitive material convertible into lithographic printing plate, which material bears a panchromatically sensitized photographic layer; bringing said sensitive material into close contact with a contact screen; exposing said sensitive material through a lens and a color separation filter to the reflected light from a continuous gradation multicolor original; and sending the exposed sensitive material to a processing bath section.

Method for direct plate making from multicolor original

A liquid developing apparatus for electrophotograph in which an electrostatic latent image surface of a photoconductive material is confronted with developing electrodes and at the same time is transferred in the liquid toner to be developed, the developing apparatus characterized by comprising a developing chamber defined by a bottom plate held substantially in a horizontal position or slanted with a downstream side in the photoconductive material transferring direction being kept at a lower level, developing electrodes facing the bottom plate at predetermined intervals and forming ceiling plates and side plates, the developing chamber being divided into a front section and a rear section with respect to the photoconductive material transferring direction, an interval between the developing electrode in the front section of the developing chamber and the electrostatic latent image surface being smaller than that between the developing electrode in the rear section of the developing chamber and the electrostatic latent image surface, both end faces on the upstream and downstream sides being opened, and at least one supply passage for the liquid toner being provided at the front section of the developing chamber, between the front and rear sections and/or at a portion of the rear section near to the front section.

Liquid developing apparatus for electrophotography

Disclosed is a method for electrophotographically making a printing plate excellent in resolving power and having a high printing endurance by using a liquid developer containing a copolymer comprising an acrylate ester or methacrylate ester having an alkyl group of 4 or more and a styrene or a styrene derivative, preferably said copolymer additionally containing an acrylate ester or a methacrylate ester having an alkyl group of 3 or less carbon atoms, more preferably said binary or ternary copolymer additionally containing a vinyl monomer having a basic group or an acidic group.

Method for making printing plates

Image recording sheet materials having a relatively hard support, e.g., printing plate sheet materials, can be simply, efficiently, automatically fed to a subsequent step without damaging a photo-sensitive surface by the present feeding method which comprises piling plural units each of which comprises a combination of an image recording sheet material having a relatively hard support and a spacing paper put on said sheet material in such a manner that the leading edge portion of the sheet material protrudes beyond the leading edge of the spacing paper and the trailing edge portion of the spacing paper protrudes beyond the trailing edge of the sheet material and the trailing edge portion of the spacing paper is held so as not to be fed and applying a feeding means to the leading edge portion of said sheet material to feed only the sheet materials to a subsequent step.

Method for feeding recording sheet materials

Disclosed is a method for making a complex layer type lithographic printing plate by forming a toner image on a printing original plate having organic electrophotographic photosensitive layer by electrophotographic process and treating non-image area other than the toner image area with an etching solution mainly composed of an alcohol solvent and/or an alkali solvent, said photosensitive layer being a complex layer type photosensitive layer which comprises a charge carrier generating layer comprising a charge carrier generating substance and a binder mainly composed of a polyamide resin soluble in alcohol solvent and a high molecular substance having compatibility with said resin and having a group soluble in alcohol solvent and/or alkali solvent and a charge carrier transport layer containing a high molecular substance having a group soluble in an etching solution mainly composed of alcohol solvent and/or alkali solvent and thereafter treating non-image area other than the toner image area with the etching solution.

Method for making complex layer type lithografic printing plate

Disclosed is a method for making a printing plate which comprises forming a toner image by electrophotography on a master plate which comprises a base and an organic photo-conductive compound-containing layer, the binder for said organic photo-conductive compound being a half ester resin of a styrene-maleic anhydride copolymer and then subjecting non-image areas other than the toner image areas to an etching treatment with a solution mainly composed of an alkali and/or an alcohol. Thus obtained printing plate is excellent in printing endurance and, besides, can be rapidly etched.

Method for making printing plates employing an organic photo-conductive

There is disclosed an electrophotographic lithographic printing plate having a precoat layer having improved water resistance and organic solvent resistance and an improved photoconductive layer which comprises:

Electrophotographic lithographic printing plate

The present invention provides a lithographic printing plate, which is made by exposing a photographic material having a silver halide photosensitive emulsion layer, developing the exposed material and treating the developed material with a conversion liquid comprising a solvent for a silver halide and an organic compound capable of forming a compound which is more stable and has a lower solubility than a soluble silver complex formed by said solvent.

Lithographic printing plate from silver halide emulsion

A lithographic printing plate which utilizes a photographic process and which is excellent in ink-repellency of non-image areas, have no stains with oily materials or fingerprints of workers, shows no reduction of ink-repellency of non-image areas and ink-receptivity of image areas with the lapse of time and can provide prints with no stains and clear images is produced by a neutralizing solution used in photographic treatment containing colloidal fine particles, preferably in combination with a hygroscopic polyol compound.

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Nagaokakyo, Japan

Shigeyoshi Suzuki