Fuji Photo Film Company, Limited

Fujifilm Corporation

Fumikazu Kobayashi

Kazuyoshi Mizutani

Katsuji Kitatani

Koichi Kawamura

Yoshiaki Inoue

Keitaro Aoshima

Ikuo Kawauchi

Kazuo Maemoto

Tsukasa Yamanaka

Norio Aoshima

Yasuhito Oshima

Akira Nagashima

Shunichi Kondo

Mitsumasa Tsuchiya

Koichiro Aono

Toshihiro Watanabe

Yoshihiro Yagi

Makoto c/o Fuji Photo Film Co Ltd Sugizaki

Yoshiaki c/o Fuji Photo Film Co Ltd Inoue

A dot pattern with a plurality of pixels representing a two-dimensional image is formed on a printing plate material by applying laser beams, which are turned on and off for each pixel depending on dot pattern data, to the printing plate material in a main scanning direction, while the laser beams are moved in an auxiliary scanning direction that is orthogonal to the main scanning direction. A threshold matrix having an array of thresholds is obtained for generating a dot where the degree of a variation of the dot periphery length in a main scanning direction is smaller, i.e., a dot where the dot periphery length in the main scanning direction has a smaller standard deviation.

Threshold matrix, a method of generating the same, and a method of reproducing color image

A normalization threshold side size Nr which serves as an index indicative of how many times the pattern frequency r is repeated in one threshold matrix is defined as Nr=N&#xd7;r/R where N represents a size of one side of the threshold matrix as the number of pixels, and the threshold array of the threshold matrix is determined such that the normalization threshold side size Nr is of an value greater than 65.

Threshold matrix, storage unit for storing threshold matrix as data, and raster image processor incorporating storage unit

A method for evaluating planographic printing plates according to the present invention includes: a step (A) of exposing a planographic printing plate precursor by irradiating a thin-line image of a one-pixel line and at least one thin-line image selected from two- to eight-pixel lines by incrementally altering the plate-surface energy; developing the exposed plate precursor with a standard developer; and identifying an exposure intensity (hereinafter, 'thin-line sensitivity') that respectively provides the images thus formed, with the same density; a step (B) of preparing another planographic printing plate precursor under the same conditions as in the step (A) and identifying the thin-line sensitivity, except that the planographic printing plate precursor is developed with a test developer; a step (C) of comparing the thin-line sensitivities respectively obtained in the steps (A) and (B); and a step (D) of adjusting plate-making conditions when the results of the comparison in the step (C) show a difference between the respective thin-line sensitivities that exceeds a predetermined value.

Method for evaluating planographic printing plates and quality-control method thereof

The present invention relates to a presensitized plate useful for making a lithographic printing plate comprising an intermediate layer and a photopolymerizable photosensitive layer on an aluminum substrate in this order, wherein the roughness of a surface of said aluminum substrate (Ra) is in the range of 0.2 to 0.55 &mgr;m and the intermediate layer comprises a polymer compound comprising at least one monomer unit having a sulfonic acid group and a method for making a lithographic printing plate by imagewise exposing the presensitized plate described above and developing the imagewise exposed presensitized plate with a developer comprising an inorganic alkali salt and a nonionic surfactant comprising a polyoxyalkylene ether group. The presensitized plate or the method of the present invention provides a lithographic printing plate showing good contrast between an image area and non-image area, no background contamination during printing, good stability with time and good printing durability.

Presensitized plate useful for making lithographic printing plate and method for making lithographic printing plate therefrom

Negative working image recording material

An image recording material comprises at least a diazonium salt represented by following general formula (1), an infrared ray absorbing agent, a cross-linking agent which is cross-linked in the presence of an acid, and a binder. The image recording material enables direct planographic printing plate production from digital computer signals by conducting recording by using an infrared laser. Further, the image recording material has excellent storability. ##STR1##

Image recording material

A negative-working image recording material is disclosed, which comprises a substance which absorbs light to generate heat, a water-insoluble and aqueous alkali-soluble resin, and a phenol derivative having in its molecule from 4 to 8 benzene rings, at least one phenolic hydroxyl group and at least two groups represented by the following general formula (I):

Negative-working image recording material

A negative type image recording material which is capable of effecting direct plate making by recording using a solid-state laser or semiconductor laser emitting an infrared-ray based on digital signals outputted from computers or the like, having components (A) to (E) which are more specifically a compound (A) which is degraded by the action of light or heat to generate an acid such as sulfonic acid or the like, a cross-linking agent (B) which has preferably two or more hydroxymethyl groups or alkoxymethyl groups, bonded to a benzene ring, which contains 3 to 5 benzene nuclei in the molecule, and which is cross-linked in the presence of an acid, such as a phenol derivative having a molecular weight of not greater than 1,200, at least one kind of alkali-soluble resin (C), an infrared absorbing agent (D), and organic basic compound (E) such as guanidine, aminomorpholine, pyridine and the like, or at least one compound selected from amino acids such as phenylalanine, tyrosine, alanylalanine, N-phenyl-.beta.-alanine, nicotinic acid and the like and derivatives thereof.

Negative type image recording material

The present invention provide a planographic printing plate comprising a substrate having thereon a recording layer which comprises at least one of a polymer compound carrying on a side chain a functional group which generates sulfonic acid under influence of an acid, base or heating; and a photo acid-generating agent or acid-generating agent; thermal base-generating agent; or an infrared ray absorbing agent, and by this structure, a high sensitive positive type planographic printing plate which can be developed with water or requires no developing is provided.

Planographic printing plate

A negative type image recording material comprising (A) an onium salt compound having sulfonic acid as the counter ion to generate sulfonic acid decomposed by light or heat, (B) a cross-linking agent cross-linkable by an acid such as a phenol derivative preferably having at least two hydroxymethyl or alkoxymethyl groups bonded to a benzene ring, (C) a polymer compound having an alkaline-soluble group such as a novolak resin, and (D) an infrared ray absorbing agent which is a dye or pigment to absorb an infrared ray having a wavelength of 720 to 1,200 nm. The negative type image recording material can allow direct production of a form plate from digital data, and provide excellent storability, a good latitude of heat treatment conditions after exposure, and excellent plate wear upon printing.

The present invention provides a negative-working image recording material which can be used as a lithographic printing plate for so-called direct plate making process comprising directly making plate from digital signal such as computer signal. A novel negative-working image recording material is provided, comprising a high-molecular compound having a weight-average molecular weight of from 5,000 to 400,000 and a repeating unit represented by the following general formula (I), and a substance which absorbs light to generate heat: ##STR1## wherein R.sup.1 represents a hydrogen atom, a halogen atom, a cyano group (--CN) or an alkyl group; R.sup.2 represents an alkyl group, an aralkyl group or an aromatic ring group; L.sup.1 represents a single bond or a phenylene group; L.sup.2 represents an alkylene group, an alkenylene group or an aromatic ring group; X represents a single bond, --O--, --OCO--, --COO--, --CONR.sup.3 --, --CONR.sup.3 CO--, --CONR.sup.3 SO.sub.2 --, --NR.sup.3 --, --NR.sup.3 CO--, --NR.sup.3 SO.sub.2 --, --SO.sub.3 --, --SO.sub.2 NR.sup.3 -- or --SO.sub.2 NR.sup.3 CO--; and R.sup.3 represents a hydrogen atom, an alkyl group, an aralkyl group or an aromatic ring group. The negative-working image recording material according to the present invention can provide a lithographic printing plate which can be exposed to infrared laser to undergo heat mode writing and exhibits a high sensitivity and developability when developed with an aqueous developer.

Disclosed is a photosensitive composition comprising a sulfonimide compound represented by formula (I):

Photosensitive composition comprising a sulfonimide compound according

A novel methoxymethyl- or hydroxymethyl-containing phenol compound represented by the following formula (I), (II), (III), (IV) or (V) is disclosed: ##STR1## wherein each R represents CH.sub.2 OCH.sub.3, CH.sub.2 OH, or H, provided that at least three of the R's are CH.sub.2 OCH.sub.3 or CH.sub.2 OH, with at least one thereof being CH.sub.2 OCH.sub.3 ; each R.sub.1 represents CH.sub.2 OCH.sub.3, CH.sub.2 OH, or H, provided that at least two of the R.sub.1 's are CH.sub.2 OH; and each R.sub.2 represents CH.sub.2 OCH.sub.3, CH.sub.2 OH, or H, provided that at least two of the R.sub.2 'S are CH.sub.2 OH.

Phenol compounds containing methoxymethyl group or hydroxymethyl group

A positive working photosensitive lithographic printing plate comprising a support having thereon a photosensitive layer comprising a positive photosensitive composition, wherein the positive photosensitive composition comprises a mixture of (a) a phenol derivative, (b) a water-soluble and aqueous alkali-soluble resin, and (c) o-quinonediazide or a mixture of a compound capable of forming an acid on exposure and a compound having at least one C--O--C group which is decomposable with an acid, and wherein the phenol derivative is a mixture of a compound represented by the following formula (I) and a compound represented by the following formula (II): ##STR1## wherein X.sup.1, X.sup.2, X.sup.3, X.sup.4, X.sup.5 and X.sup.6 are the same or different and each represents --CH.sub.2 OH or a hydrogen atom, provided that at least three of them are each --CH.sub.2 OH; ##STR2## wherein Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4, Y.sup.5 and Y.sup.6 are the same or different and each represents --CH.sub.2 OCH.sub.3, --CH.sub.2 OH or a hydrogen atom, provided that at least three of them are each --CH.sub.2 OCH.sub.3 or --CH.sub.2 OH, and at least one of the three is --CH.sub.2 OCH.sub.3.

Growing community of inventors

Shizuoka-ken, Japan

Fumikazu Kobayashi