Mitsubishi Paper Mills Limited

Dainippon Screen Mfg. Co., Ltd.

Kyonosuke Yamamoto

Eiji Kanada

Shigeyoshi Suzuki

Kazunaka Endo

Toshiro Kondo

Jun Urasaki

Eiji Miyasaka

Tsuyoshi Harada

Sadao Kuriu

Kazuyoshi Yamamoto

Masaharu Kimura

Yoshikazu Takano

Akira Kunihiro

Isamu Maruyama

Kunihiro Tanabe

Kazuo Yokoyama

Yasu Sato

Yasuhiro Kawaguchi

Fumito Fukuhara

Kazuyuki Ebara

Masaharu Tatikawa

Kazuhito Hasegawa

Satoshi Katano

The apparatus for coating a photosensitive material (M) with a processing liquid comprises an activator coating mechanism (43) for metering a constant amount of activator to apply the metered activator to the photosensitive surface of the photosensitive material fed by the pair of introduction rollers. The activator is supplied form a plurality of discharge holes (121) bored in a pipe (122) and is once received by a receiving portion (124). The activator is diffused horizontally and flows downwardly through a plurality of openings (123) bored at the bottom of the receiving portion onto a coating roller (125). The activator is diffused again at the contact between the coating roller and a diffusion film (126) and is coated to the photosensitive material by the coating roller.

Apparatus for processing photosensitive material

A screen dot image recording method is disclosed in which whether or not each minimum recording element of an image recording system is to be recorded is determined on the basis of a gray level obtained from an original. A matrix is prepared which has a size capable of including each of screen dot blocks arranged at a predetermined pitch in directions inclined at a predetermined angle with respect to an orthogonal coordinate system based on recording directions of the recording system and has a plurality of matrix elements one of which is defined as a reference element. From among reference points which have a fixed positional relationship therebetween in the screen dot blocks, there is determined a reference point which exists in a screen dot block including a recording element. Another recording element has a coordinate value obtained by converting the coordinate of the determined reference point into an integer value. There is selected a matrix element having a positional relation of that matrix element with the reference element of the matrix which is the same as a positional relation of the recording element with said another recording element. The selected matrix element is compared as a threshold value with a gray level assigned to the recording element to determine whether or not the recording element is to be recorded as a part of a screen dot. Thereby, there is recorded a screen dot image which has any screen angle and any screen pitch and in which each screen dot has a desired form and a desired size corresponding to a gray level.

Screen dot image recording method

A method for forming an image on a dye. The dye absorbing visible light of a first wavelength, but not visible light of a second wavelength. The dye is decolorized when visible light of the first and second wavelength irradiate the dye simultaneously. Decolorization will be effected only if visible light of the first wavelength and visible light of the second wavelength are simultaneously applied. The method utilizes lasers as the source of the visible light of the first and second wavelengths; thus insuring formation of high resolution images.

Method for image formation

A method for lithographic printing of paginal publications which comprises applying onto a flexible supporting base two or more lithographic printing plates arranged in the rotational direction of a master cylinder and to form such a structure with front and rear edge portions of the adjacent lithographic printing plates as to prevent penetration of damping solution between the supporting base and the lithographic printing plates, the portion of said structure receiving substantially no ink. This supporting base is mounted on a master cylinder of a printing machine and printing is carried out.

Method for preventing penetration of damping solution between supporting

Disclosed is a direct making of multicolor printing plates by the procedure of exposing a photosensitive material (P) of the lithographic type for making a black plate to an original bearing both the continuous tone image and the line images. The said procedure comprises (1) exposure to the continuous tone image which is performed by exposing the sensitive material (P) through a contact screen to the original in which the line images are covered with a mask (M-1) having an optical reflectance of 2% or less and the continuous tone image is covered with a mask (M-2) having a large optical reflectance, then again exposing, in the absence of contact screen, the sensitive material (P) to the original in which the line images are covered with said mask (M-1), and the mask (M-2) for the continuous tone image is removed, and (2) exposure to the line images which is performed by exposing the sensitive material (P) to the original in which the continuous tone image is covered with the mask (M-1).

Method for direct making of lithographic printing plates

Disclosed is a lithographic printing plate material which comprises a support and at least an undercoat layer, a silver halide emulsion layer and a catalytic layer containing physical development nuclei provided in this order on said support and which utilizes silver complex diffusion transfer process, wherein content of calcium ion in at least one of lime treated gelatin-containing layers is 1000 ppm or less.

Lithographic printing plate excellent in printing endurance

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

Growing community of inventors

Tokyo, Japan

Kyonosuke Yamamoto