DE60304528T2 - Lithographic printing plate precursor - Google Patents

Abstract

A lithographic printing plate precursor containing: an aluminum support; and a photosensitive layer containing a water-insoluble and alkali-soluble resin and an infrared absorber, wherein the photosensitive layer has a coating weight of 0.5 to 3 g/m<2> and a thickness distribution with a relative standard deviation of 20% or less.

Description

FIELD OF THE INVENTION

These This invention relates to a lithographic printing plate precursor which is particularly suitable for the Direct-to-disk (DTP) or computer-on-disk (CTP) technology is where a picture in direct response to digital signals from a Computer is generated.

BACKGROUND OF THE INVENTION:

The Last years have seen a remarkable laser development. In particular, solid-state lasers and semiconductor lasers that are used in the near-infrared operate to infrared range, which have high performance yet compact, easily available. These lasers are very popular as an exposure light source for the DTP technology useful.

One Lithographic printing plate precursor for the DTP imaging with an infrared laser has a photosensitive layer, which is essentially an alkali-soluble Binder resin and an infrared absorber that absorbs light, for heat to generate (hereinafter sometimes referred to as "IR dye") includes. The IR dye and the alkali-soluble Binder resin interact with each other, and the IR dye serves as a dissolution inhibitor, the alkali solubility of the resin substantially reduced. In the imagewise exposure the IR dye absorbs in an exposed area (non-image area) Light to heat generate, thereby reducing the interaction between the IR dye and the binder resin is reduced. As a result, the binder resin becomes in the exposed area alkali-soluble and can with an alkali developer be removed to a lithographic printing plate with image and non-image areas to disposal to deliver.

If a grained and anodized aluminum plate is used as a carrier, diffused a part of the heat generated at the interface with the carrier ins Inside of the carrier, before the imaging reaction, i. the alkali solubilization sufficiently progresses, because the carrier much stronger thermally conductive as the photosensitive layer. It would turn out that the Part of the exposed photosensitive layer near the interface with the carrier insufficient solubility reached in a developer and tends to stay there, where it should be removed to become a non-image area. The remaining film is noticeable where the photosensitive Layer a large thickness, i. a large basis weight, has. To that To avoid problem of the remaining film, it is necessary to use a highly active developer or the basis weight to reduce. However, such an approach can lead to an image of the image area is missing. That means a small change the developer activity, by the electrical conductivity represented by a developer can easily result in developmental failure, e.g. that a movie remains or an image is missing. A problem in the essentially associated with IR-sensitive lithographic printing plate precursors, that freedom of development is considerably narrower than with conventional ones presensitized plates. To solve this problem are various improvements of lithographic printing plate precursor materials, the opposite IR lasers are sensitive, have been proposed, what procedure to improve the developability of a photosensitive Layer in the border areas of the interface with a carrier and Method for suppressing developer solubility an unexposed photosensitive layer, however So far no satisfactory results have been achieved.

If the part of a photosensitive layer that should remain, to create an image area is damaged by any cause, would the Part continues for a development with a developer become vulnerable. That means, the Printing plate precursor this type is opposite damage very sensitive to scratching during practical use. For example, image missing was caused by scratching by light Contact with other objects due to, for example, shocks handling, sliding contact with an intermediate sheet or a finger touch occur. Therefore, the printing plate precursors of this type are known in the art the technique very difficult to handle.

In order to solve the above-mentioned problems, JP-A-2002-72458 proposes a lithographic printing plate precursor in which the amount of aluminum etched by alkali etching an aluminum plate is 0.5 to 4 g / m ² and the middle one Thickness of the thinnest 10% of a photosensitive layer formed on projections of the aluminum support 0.2 to 2 μm observed under a SEM. This plate precursor still can not be considered sufficient in scratch resistance and development freedom.

SUMMARY OF THE INVENTION:

A The object of the present invention is to provide a lithographic printing plate precursor for Available too which has a great freedom of development and hardly suffers from image missing by scratching.

As a result of extensive research, the inventors have found that the above object is achieved by a lithographic printing plate precursor comprising an aluminum support, which is preferably prepared by subjecting an aluminum plate to at least graining and alkali etching, and a photosensitive layer comprising a water-insoluble and alkali-soluble Resin and an infrared absorber, wherein the photosensitive layer has a basis weight of 0.5 to 3 g / m ² and a thickness distribution having a relative standard deviation of 20% or less. The basis weight of the photosensitive layer is preferably 0.7 to 1.5 g / m ² , more preferably 0.7 to 1.2 g / m ² . Too low a basis weight results in a poor press life, and a too large basis weight results in an increased stress during development.

It it is assumed that the specific basis weight (i.e., the film thickness) and the film thickness distribution of a photosensitive layer due to for the following reasons lead to improved freedom of development. Because an aluminum carrier one Lithographic printing plate precursor generally a surface roughness that is characterized by graining and other surface treatments is prepared, has the photosensitive formed thereon Layer generally on a non-uniform thickness. The image missing tends to occur in areas with a small thickness, while the Film remains prone to being in areas with a large thickness occur. Therefore, it is believed that providing a photosensitive Layer with a uniform Thickness eliminate the problems of image defect and film remaining becomes.

you assumes that the specific basis weight (i.e., the film thickness) and the film thickness distribution of a photosensitive layer due to for the following reasons leads to improved scratch resistance. Image missing because of scratching tends to occur in areas of low film thickness. Therefore, the provision of a photosensitive layer having a uniform Eliminate thick areas with an extremely small thickness and that Solve image corruption problem due to scratching.

The Inventors made a number of samples and the thickness the photosensitive layer provided on a granular support is accurately measured to obtain a relative standard deviation. As a result, they found that a lithographic printing plate precursor having a specific film thickness and a specific film thickness distribution solves the problem of the invention and have made the present invention.

BRIEF DESCRIPTION OF THE DRAWING:

1 schematically illustrates a device configuration used to carry out continuous application and drying of a coating film.

DETAILED DESCRIPTION OF THE INVENTION:

The lithographic printing plate precursor of the present invention comprises an aluminum support prepared by subjecting an aluminum plate to at least graining and alkali etching, and a photosensitive layer comprising a water-insoluble and alkali-soluble resin and an infrared absorber, wherein the photosensitive layer has a basis weight of 0.5 to 3 g / m ² , preferably 0.7 to 1.5 g / m ² , more preferably 0.7 to 1.2 g / m ² , and has a thickness distribution with a relative standard deviation of 20% or less.

The relative standard deviation of the film thickness distribution is preferably 15% or less, more preferably 10% or less.

Methods for controlling the relative standard deviation of the film thickness distribution by 20% or less include, but are not limited to, a method which comprises rapidly drying the coating layer by blowing hot compressed air or permeating the coating layer with a hot roll, a method comprising Adjusting the concentration of the coating composition of the photosensitive layer, and a method comprising adjusting the viscosity or the surface tension of the coating composition by properly selecting a solvent or various comprises additives to be used herein.

1 shows a configuration of an apparatus for continuously applying a coating composition to a grained aluminum net as a carrier and for continuously drying the coating layer.

In the 1 The device shown has a coating head ( 2 ) for applying a photosensitive coating composition to a grained aluminum net ( 1 ), a first drying zone ( 3 ), wherein the coating film is subjected to hot-air drying and rapid drying by blowing high-pressure air, and a second drying zone ( 4 ), in which the coating film is subjected to hot-air drying. The first drying zone ( 3 ) is equipped with a feed inlet ( 5 ), through which hot air is introduced, a high-pressure air generator ( 9 ), to achieve rapid drying, a heat exchanger ( 10 ), a pressure indicator ( 11 ) High pressure air nozzles ( 12 ), Air flow regulating dampers ( 18 ) and ( 19 ) and a vent ( 6 ) for discharging hot air. The second drying zone ( 4 ) has a hot air supply opening ( 7 ) and a hot air outlet opening ( 8th ) on. Guide rollers ( 13 ) to ( 17 ) are at appropriate positions in the device ( 1 ) arranged around the aluminum mesh ( 1 ) to wear.

In the device ( 1 ) the grained aluminum net ( 1 ) continuously at a speed of 5 to 150 m / min, is passed through the coating head ( 2 ) is coated with 5 to 40 ml / m ^{2 of} a photosensitive coating composition, and is placed in the first drying zone ( 3 ). In the first drying zone ( 3 ) is hot air, typically at a temperature of 50 to 150 ° C, through the feed opening ( 5 ) to the coated network ( 1 ) to dry. Solvent gas from the coating composition is mixed with hot air through the vent (FIG. 6 ) omitted. The coating film containing the hot air near the inlet of the first drying zone ( 3 ) is usually still wet.

The high-pressure air nozzles ( 12 ) are each with their slots over the current network ( 1 ) are arranged at substantially right angles to the network running direction. The still wet coating film on the net ( 1 ) is due to the high velocity air flow from the nozzles ( 12 ) dried extremely quickly.

High pressure air is in the high pressure air generator ( 9 ), which has a compressor or a high-pressure fan, generated with the heat exchanger ( 10 ) heated to 50 to 200 ° C, through the damper ( 18 ) and ( 19 ) to a desired air flow, and to the first drying zone ( 3 ) through the slot nozzles ( 12 ). The high-pressure air having the thus-regulated desired temperature and flow rate is vigorously directed against the wet coating film, whereby the solvent of the coating film is evaporated in an extremely short time to form a photosensitive layer. The air pressure in the nozzles ( 12 ) is usually about 300 mmAq (H ₂ O) to 3 kg / cm ² , preferably about 1,000 mmAq to 1 kg / cm ² . The velocity of the air from the nozzles ( 12 ) is about 20 to 300 m / sec. The slot width of the nozzles ( 12 ) is about 0.1 to 5 mm, preferably 0.3 to 1 mm. The blowing angle of the high-pressure air with respect to the aluminum support ( 1 ) is 0 to 90 °, preferably 10 to 60 °. The number of nozzles used in the in 1 may be from 1 to about 8.

The drying with high-pressure air is preferably combined with drying by means of a heating roller. For example, the guide roller ( 14 ) are replaced by a heat roller. In this case, the surface temperature of the heating roller can be maintained at 80 to 200 ° C by circulating a heating medium such as steam inside the roller. The heating roller transfers heat energy from the underside of the aluminum net by heat conduction. The combined use of such a heating roller leads to a more rapid evaporation of the solvent than when drying with high pressure air alone and leads to a more uniform distribution of the film thickness.

Thus, the coating film in the first drying zone ( 3 ) are dried rapidly to give a dry film with a certain thickness distribution. The network ( 1 ) is then transferred to the second drying zone ( 4 ), where it is heated with hot air from 100 to 150 ° C coming from the feed opening ( 7 ), is heated. By this second drying, the solvent content remaining as a trace in the film is reduced to 30 to 200 mg / m ² . The solvent gas is passed through the outlet ( 8th ) led out of the system.

Consequently becomes a desired film thickness distribution by these drying operations reached.

While in the embodiment described above the coating layer first with hot air and then with high pressure air is dried, can be dispensed with the hot air drying. That means it is possible that the net with the high-pressure air, immediately after it is coated was, can be dried.

The present invention is preferably carried out by continuous application, followed by continuous drying using such a device as in 1 shown, executed. In terms of productivity, it is preferable to carry out the graining of an aluminum plate also in a continuous manner, eg by adding means for graining (upstream) the coating head ( 2 ).

The relative standard deviation of the thickness distribution of the photosensitive layer is determined as follows. A 1 cm ² test piece excised from a printing plate precursor is analyzed without deposition on a Jeol JXA8000 electron probe microanalyser (EPMA) to measure the characteristic X-ray intensity of carbon by a stage scan method under conditions of an acceleration voltage of 20 kV. a sample voltage of about 5 × 10 ⁷ A, a sample diameter of 2 μm, a measurement interval of 2 μm in the x-direction and 2 μm in the y-direction, a measurement point number of 512 × 256, a dwell time of 50 ms and a diffraction angle (θ) of 46.4 °. LDE1H is selected as an LDE (layered dispersive element) analyzer crystal. A relative standard deviation RSD is calculated from a mean characteristic X-ray intensity I of 512 × 256 measurement points and the standard deviation σ according to the equation RSD = σ / I × 100 (%).

The Elements corresponding to the inventive Compose lithographic printing plate precursor, are described below.

(1) Alkali-soluble Resin:

The Photosensitive layer comprises a water-insoluble and alkali-soluble Resin (hereinafter simply referred to as alkali-soluble resin or polymer). The alkali-soluble Polymer includes a homopolymer having an acidic group in its Main chain and / or its side chain contains, a copolymer containing the unit of the homopolymer, and a mixture of such a homopolymer and / or a copolymer. Therefore, the photosensitive layer be removed with an alkaline developer.

While either as alkali-soluble a known polymer can be used, one which is preferred has a functional group that is a phenolic Hydroxyl group, a sulfonamide group and an active imide group selected becomes. Non-limiting Examples of such alkali-soluble Polymers are given below.

polymers with a phenolic hydroxyl group include novolac resins, such as phenol-formaldehyde resins, m-cresol-formaldehyde resins, m-cresol-formaldehyde resins, p-cresol-formaldehyde resins, Xylenol-formaldehyde resins, mixed m / p-cresol-formaldehyde resins and mixed phenol / cresol (m, p or mixed m / p) formaldehyde resins; pyrogallol acetone; and polymers having a phenolic hydroxyl group in the side chain. The polymers with a phenolic hydroxyl group in the side chain include those obtained by polymerizing a low molecular weight monomer having a phenolic hydroxyl group and a polymerizable unsaturated bond, either alone or with a comonomer.

The Monomer having the phenolic hydroxyl group includes acrylamides, Methacrylamides, acrylic esters and methacrylic esters, each one having phenolic hydroxyl group, and hydroxystyrenes. suitable Examples are N- (2-hydroxyphenyl) acrylamide, N- (3-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) acrylamide, N- (2-hydroxyphenyl) methacrylamide, N- (3-hydroxyphenyl) methacrylamide, N- (4-hydroxyphenyl) methacrylamide, o-hydroxyphenyl acrylate, m-hydroxyphenyl acrylate, p-hydroxyphenyl acrylate, m-hydroxyphenyl methacrylate, p-hydroxyphenyl methacrylate, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (2-hydroxyphenyl) ethyl acrylate, 2- (3-hydroxyphenyl) ethyl acrylate, 2- (4-hydroxyphenyl) ethyl acrylate, 2- (2-hydroxyphenyl) ethyl methacrylate, 2- (3-hydroxyphenyl) ethyl methacrylate and 2- (4-hydroxyphenyl) ethyl methacrylate. These resins with a phenolic Hydroxyl group can either individually or in a combination of two or more be used thereof. Polycondensates between phenol, substituted with an alkyl group of 3 to 8 carbon atoms, and formaldehyde, such as t-butylphenol-formaldehyde resin, and an octylphenol-formaldehyde resin may be used in combination as taught in US Pat. No. 4,123,279.

Alkali-soluble polymers having a sulfonamide group include those prepared by polymerizing a monomer having a sulfonamide group, either alone or with a comonomer. Monomers having a sulfonamide group include low molecular weight compounds having a sulfonamide group having at least one hydrogen atom on the nitrogen atom (-NH-SO ₂ -) and a polymerizable unsaturated bond in the molecule. Preferred are those having an acryloyl group, an allyl group or a vinyloxy group and a monosubstituted or unsubstituted aminosulfonyl group or a substituted sulfonylimino group in the molecule.

Alkali-soluble polymers with an active imide group include those obtained by polymerizing a low molecular weight monomer containing an active imide group and a polymerizable unsaturated Bond in his molecule , either alone or with a comonomer become. Examples of such a monomer are N- (p-toluenesulfonyl) methacrylamide and N- (p-toluenesulfonyl) acrylamide.

Also For example, the preferred alkali-soluble resins include copolymers that prepared by copolymerizing at least two monomers which are mentioned under (1) the monomer having a phenolic hydroxyl group, (2) the monomer having a sulfonamide group and (3) the monomer with an active amide group, and copolymers which by copolymerizing at least two of the monomers (1), (2) and (3) and (4) other comonomer (s) are produced. When copolymerizing of the monomer (1) with the monomer (2) and / or the monomer (3) a preferred copolymerization ratio of (1) to (2) and / or (3) 50:50 to 5:95, especially 40:60 to 10:90.

The A copolymer prepared from the monomers mentioned under (1), (2) and (3) and the comonomer (4), preferably contains at least 10 mol%, in particular 20 mol% or more, of the units, which originate from these monomers which are responsible for alkali solubility contribute. With an amount of less than 10 mol% of the units, the alkali solubility contribute, the copolymer tends to insufficient in alkali solubility and can not have improved freedom of development.

The Comonomers (4) which are copolymerizable with the monomers (1), (2) and (3) include, but are not limited to, the following connection groups (m1) to (m12).

• (m1) Acrylsäureester und Methacrylsäureester mit einer aliphatischen Hydroxylgruppe, wie 2-Hydroxyethylacrylat und 2-Hydroxyethylmethacrylat.
• (m2) Alkylacrylate, wie Methylacrylat, Ethylacrylat, Propylacrylat, Butylacrylat, Amylacrylat, Hexylacrylat, Octylacrylat, Benzylacrylat, 2-Chlorethylacrylat und Glycidylacrylat.
• (m3) Alkylmethacrylate, wie Methylmethacrylat, Ethylmethacrylat, Propylmethacrylat, Butylmethacrylat, Amylmethacrylat, Hexylmethacrylat, Cyclohexylmethacrylat, Benzylmethacrylat, 2-Chlorethylmethacrylat und Glycidylmethacrylat.
• (m4) Acrylamide, Methacrylamide und deren Derivate, wie N-Methylolacrylamid, N-Ethylacrylamid, N-Hexylmethacrylamid, N-Cyclohexylacrylamid, N-Hydroxyethylacrylamid, N-Phenylacrylamid, N-Nitrophenylacrylamid und N-Ethyl-N-phenylacrylamid.
• (m5) Vinylether, wie Ethylvinylether, 2-Chlorethylvinylether, Hydroxyethylvinylether, Propylvinylether, Butylvinylether, Octylvinylether und Phenylvinylether.
• (m6) Vinylester, wie Vinylacetat, Vinylchloracetat, Vinylbutyrat und Vinylbenzoat.
• (m7) Styrol und dessen Derivate, wie α-Methylstyrol, Methylstyrol und Chlormethylstyrol.
• (m8) Vinylketone, wie Methylvinylketon, Ethylvinylketon, Propylvinylketon und Phenylvinylketon.
• (m9) Olefine, wie Ethylen, Propylen, Isobutylen, Butadien und Isopren.
• (m10) N-Vinylpyrrolidon, Acrylnitril und Methacrylnitril.
• (m11) Ungesättigte Imide, wie Maleimid, N-Acryloylacrylamid, N-Acetylmethacrylamid, N-Propionylmethacrylamid und N-(p-Chlorbenzoyl)methacrylamid.
• (m12) Ungesättigte Carbonsäuren, wie Acrylsäure, Methacrylsäure, Maleinsäureanhydrid und Itaconsäure.

The alkali-soluble copolymers can be prepared by known techniques involving graft copolymerization, block copolymerization and random copolymerization.

• (m1) Acrylic acid esters and methacrylic acid esters having an aliphatic hydroxyl group such as 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate.
• (m2) alkyl acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, benzyl acrylate, 2-chloroethyl acrylate and glycidyl acrylate.
• (m3) Alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-chloroethyl methacrylate and glycidyl methacrylate.
• (m4) acrylamides, methacrylamides and their derivatives such as N-methylolacrylamide, N-ethylacrylamide, N-hexylmethacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide and N-ethyl-N-phenylacrylamide.
• (m5) vinyl ethers, such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether.
• (m6) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.
• (m7) Styrene and its derivatives such as α-methylstyrene, methylstyrene and chloromethylstyrene.
• (m8) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone.
• (m9) Olefins such as ethylene, propylene, isobutylene, butadiene and isoprene.
• (m10) N-vinylpyrrolidone, acrylonitrile and methacrylonitrile.
• (m11) Unsaturated imides such as maleimide, N-acryloylacrylamide, N-acetylmethacrylamide, N-propionylmethacrylamide and N- (p-chlorobenzoyl) methacrylamide.
• (m12) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride and itaconic acid.

The Homo- or copolymers containing at least one of the monomers (1) to (3) preferably have a weight average molecular weight (Mw) of more than 2,000 and a number average molecular weight (Mn) of more than 500, in particular a Mw of 5,000 to 300,00 and a Mn of 800 to 250,000, and a molecular weight distribution (Mw / Mn) from 1.1 to 10.

The Phenol-formaldehyde resins, the cresol-formaldehyde resins, and the like preferably have a Mw of 500 to 20,000 and a Mn of 200 up to 10,000.

The above alkali-soluble Polymers can either individually or as a combination of two or more be used thereof. The alkali-soluble polymers are in in an amount of 30 to 99% by weight, preferably 40 to 95% by weight preferably from 50 to 90% by weight, based on the total solids content the photosensitive layer used. At a salary of less than 30% by weight of the alkali-soluble Polymer, the photosensitive layer has a reduced durability on. A content of alkali-soluble Polymer exceeding 99% by weight, results in a reduction of both the sensitivity as well as the durability.

(2) Infrared absorber:

Of the Infrared absorber used in the photosensitive layer (hereinafter sometimes referred to as "IR dye") not particularly limited as long as it can absorb infrared rays of light to generate heat. It can various known IR dyes are used.

Commercially available IR dyes and IR dyes known from the literature (e.g., Senryo Binran, The Society of Synthetic Organic Chemistry, Japan (editor), 1970) be used. helpful Dyes include azo dyes, metal complex azo dyes, pyrazolone azo dyes, Anthraquinone dyes, phthalocyanine dyes, carbonium dyes, Quinoneimine dyes, methine dyes and cyanine dyes. From these are given the suitability for lasers, the infrared light or near-infrared light, those which prefer infrared light or absorb near-infrared light.

Infrared- or near-infrared absorbing dyes include cyanine dyes, JP-A-58-125246, JP-A-59-84356, JP-A-59-202289 and JP-A-60-78787 are described; Methine dyes disclosed in JP-A-58-173696, JP-A-58-181690 and JP-A-58-194595; Naphthoquinone dyes which are in JP-A-58-112793, JP-A-58-224793, JP-A-59-48187, JP-A-59-73996, JP-A-60-52940 and JP-A-60-63744; Squarylium dyes that are in JP-A-58-112792; and cyanine dyes used in GB PS 434 875 are described.

The Near-infrared sensitizers disclosed in U.S. Patent 5,156,938, are also suitable as dyes. Particularly preferred dyes include arylbenzo (thio) pyrylium salts described in U.S. Patent 3,881,924 are; Trimethine thiapyrylium salts disclosed in U.S. Patent 4,327,169 (corresponding to U.S. Pat JP-A-57-142645); Pyrylium compounds described in JP-A-58-181051, JP-A-58-220143, JP-A-59-41363, JP-A-59-84248, JP-A-59-84249, JP-A-59-146063 and JP-A-59-146061; Cyanine dyes described in JP-A-59-216146 are described; Pentamethine thiopyrylium salts described in U.S. Patent 4,283 475 are described; Pyrylium compounds described in JP-B-5-13514 and JP-B-5-19702; and Epolight III-178, III-130 and III-125 (trade names, available from Epolin, Inc.). The near-infrared absorbing dyes by the formulas (I) and (II) shown in U.S. Patent 4,756 993 are also particularly preferred.

Of the Infrared absorber is based on the total solids content of photosensitive layer, in an amount of 0.01 to 50% by weight, preferably 0.1 to 50% by weight, more preferably 0.1 to 30% by weight, used. Infrared absorbent contents of less than 0.01% tend to cause insufficient sensitivity. Infrared absorber content of more than 50% can the uniformity and durability of the photosensitive layer.

(3) dissolution inhibitor:

The Photosensitive layer may contain a dissolution inhibitor which the durability of an unexposed area versus dissolution in an alkali developer strengthen can. The dissolution inhibitors include, but are not limited to, quaternary ammonium salts and polyethylene glycol compounds.

The quaternary ammonium salts include tetraalkylammonium salts, trialkylarylammonium salts, dialkyldiarylammonium salts, alkyltriarylammonium salts, tetraarylammonium salts, cyclic ammonium salts and bicyclic ammonium salts. Specific examples are tetrabutylammonium bromide, tetrapentylammonium bromide, tetrahexylammonium bromide, Tetraacetylammoniumbromid, tetralaurylammonium, tetraphenylammonium bromide, tetranaphthylammonium, tetrabutylammonium chloride, tetrabutylammonium iodide, Tetrastearylammoniumbromid, lauryltrimethylammonium bromide, stearyltrimethylammonium bromide, Behenyltrimethylammoniumbromid, Lauryltriethylammoniumbromid, Phenyltrimethylammaniumbromid, 3-trifluoromethylphenyltrimethylammonium, benzyltrimethylammonium bromide, Dibenzyldimethylammo ammonium bromide, distearyldimethylammonium bromide, tristearylmethylammonium bromide, benzyltriethylammonium bromide, hydroxyphenyltrimethylammonium bromide and N-methylpyridinium bromide.

A suitable addition amount of the quaternary ammonium salt is based on the total solids content of the photosensitive layer, 0.1 to 50% by weight, in particular 1 to 30% by weight. An addition of less as 0.1% is less effective. An addition of more than 50% can the film-forming ability of the binder resin adversely affect.

dargestellt werden, worin R¹ einen mehrwertigen Alkoholrest oder einen mehrwertigen Phenolrest darstellt; R² stellt ein Wasserstoffatom, eine substituierte oder unsubstituierte Alkyl-, Alkenyl-, Alkinyl- oder Alkyloylgruppe mit 1 bis 25 Kohlenstoffatomen oder eine substituierte oder unsubstituierte Aryl- oder Aryloylgruppe mit 6 bis 25 Kohlenstoffatomen dar; R³ stellt eine substituierte oder unsubstituierte Alkylengruppe dar; m ist im Durchschnitt eine ganze Zahl von 10 oder grösser; und n ist eine ganze Zahl von 1 bis 4.The polyethylene glycol compounds as dissolution inhibitors include compounds represented by the formula:

wherein R ^{1 represents} a polyhydric alcohol radical or a polyhydric phenol radical; R ² represents a hydrogen atom, a substituted or unsubstituted alkyl, alkenyl, alkynyl or alkyloyl group having 1 to 25 carbon atoms or a substituted or unsubstituted aryl or aryloyl group having 6 to 25 carbon atoms; R ³ represents a substituted or unsubstituted alkylene group; On average, m is an integer of 10 or greater; and n is an integer from 1 to 4.

The Polyethylene glycol compounds of the above formula include polyethylene glycol, Polypropylene glycol, polyethylene glycol alkyl ethers, polypropylene glycol alkyl ethers, Polyethylene glycol aryl ether, polypropylene glycol aryl ether, polyethylene glycol alkyl aryl ether, Polypropylene glycol alkylaryl ether, polyethylene glycol glyceryl ether, polypropylene glycol glyceryl ether, Polyethylene glycol sorbitol ether, polypropylene glycol sorbitol ether, Polyethylene glycol fatty acid ester, Polypropylene glycol fatty acid ester, polyethylene glycolated ethylenediamines, polypropylene glycolated ethylenediamines, polyethylene glycolated diethylenetriamine and polypropylene glycolated Diethylenetriamines.

specific Examples of the polyethylene glycol compounds are polyethylene glycol 1,000, polyethylene glycol 2,000, polyethylene glycol 4,000, polyethylene glycol 10,000, polyethylene glycol 20,000, polyethylene glycol 50,000, polyethylene glycol 100,000, polyethylene glycol 200,000. Polyethylene glycol 500,000, polypropylene glycol 1,500, Polypropylene glycol 3,000, polypropylene glycol 4,000, polyethylene glycol methyl ether, Polyethylene glycol ethyl ether, polyethylene glycol phenyl ether, polyethylene glycol dimethyl ether, Polyethylene glycol diethyl ether, polyethylene glycol diphenyl ether, polyethylene glycol telluryl ether, Polyethylene glycol dilauryl ether, polyethylene glycol nonyl ether, polyethylene glycol cetyl ether, Polyethylene glycol stearyl ether, polyethylene glycol distearyl ether, Polyethylene glycol behenyl ether, polyethylene glycol dibehenyl ether, Polypropylene glycol methyl ether, polypropylene glycol ethyl ether, polypropylene glycol phenyl ether, Polypropylene glycol dimethyl ether, polypropylene glycol diethyl ether, polypropylene glycol diphenyl ether, Polypropylene glycol telluryl ether, polypropylene glycol dilauryl ether, Polypropylene glycol nonyl ether, polyethylene glycol acetate, polyethylene glycol diacetate, Polyethylene glycol zoate, polyethylene glycol laurate, polyethylene glycol dilaurate, Polyethylene glycol nonylate, polyethylene glycol cetylate, polyethylene glycol stearate, Polyethylene glycol distearate, polyethylene glycol behenate, polyethylene glycol dibehenate, Polypropylene glycol acetate, polypropylene glycol diacetate, polypropylene glycol zoate, Polypropylene glycol dibenzoate, polypropylene glycolollaurate, polypropylene glycol dilaurate, Polypropylene glycol nonylate, polyethylene glycol glyceryl ether, polypropylene glycol glyceryl ether, Polyethylene glycol sorbitol ether, polypropylene glycol sorbitol ether, polyethylene glycolated ethylenediamine, polypropylene glycolated Ethylenediamine, polypropylene glycolated ethylenediamine, polyethylene glycolated Diethylenetriamine, polypropylene glycolated diethylenetriamine and polyethylene glycolated pentamethylenehexamine.

A Recommended addition amount of the polyethylene glycol compound is 0.1 to 50% by weight, in particular 1 to 30% by weight, on a solids basis of the total solids content the photosensitive layer. An addition of less than 0.1 % leads to a low dissolution inhibiting Effect. When the polyethylene glycol compound is added in amounts which exceeds 50%, can the surplus, not capable is to act interactively on a binder resin, the penetration accelerate a developer, resulting in negative influences the image generation results.

The Addition of the dissolution inhibitor leads to a reduction in sensitivity, effectively by the addition a lactone compound is balanced. If a developer in penetrates an exposed area, the lactone compound reacts with the developer to form the corresponding carboxylic acid compound, the to the resolution contributes to the exposed area, i.e. she leads to improved sensitivity.

worin X¹, X², X³ und X⁴, die gleich oder unterschiedlich sein können, jeweils ein(e) substituierte(s) oder unsubstituierte(s) Atom oder atomare Gruppe darstellt, die den Ring vervollständigen; zumindest eines von X¹, X² und X³ in Formel (L-I) und zumindest eines von X¹, X², X³ und X⁴ in Formel (L-II) besitzt jeweils eine elektronenanziehende Gruppe oder eine mit einer elektronenanziehenden Gruppe substituierte Gruppe.Lactone compounds useful for this purpose include, but are not limited to, Compounds represented by formulas (LI) and (L-II):

wherein X ¹ , X ² , X ³ and X ⁴ , which may be the same or different, each represents a substituted or unsubstituted atom or atomic group completing the ring; at least one of X ¹ , X ² and X ³ in formula (LI) and at least one of X ¹ , X ² , X ³ and X ⁴ in formula (L-II) each has an electron-attracting group or an electron-attracting group-substituted group Group.

The atom or atomic group represented by X ¹ , X ² , X ³ or X ⁴ is a non-metal atom having two single bonds or an atomic group containing such a non-metal atom. Preferred non-metal atoms or atomic groups are selected from methylene, sulfinyl, carbonyl, thiocarbonyl, sulfonyl, sulfur, oxygen and selenium. A methylene group, a carbonyl group and a sulfonyl group are more preferable.

At least one of X ¹ , X ² and X ³ in formula (LI) and at least one of X ¹ , X ² , X ³ and X ⁴ in formula (L-II) each have an electron attracting group. As used herein, the term "electron withdrawing group" refers to a group having a Hammett positive substituent constant σp. With respect to the Hammett substituent constant, reference may be made to Journal of Medicinal Chemistry (1973), Vol. 16, No. 11, 1207-1216 Examples of such electron-attracting groups include halogen atoms [eg, fluorine (σp: 0.006), bromine (σp: 0.23), and iodine (σp: 0.18)]; trihaloalkyl [eg, tribromomethyl (σp: 0.29), trichloromethyl (σp: 0.33) and trifluoromethyl (σp: 0.54)], a cyano group (σp: 0.66), a nitro group (σp: 0.78), aliphatic aryl or heterocyclic sulfonyl groups [eg methanesulfonyl (σp: 0.72)]; aliphatic aryl or heterocyclic acyl groups [eg, acetyl (σp: 0.50) and benzoyl (σp: 0.53)], alkynyl groups [eg, ethynyl (σp: 0.23)], aliphatic aryl or heterocyclic oxycarbonyl groups [eg, methoxycarbonyl (σp: 0.45) and phenoxycarbonyl (σp: 0.44)]; a carbamoyl group (σp: 0.36); a Sul famoyl group (σp: 0.57), a sulfoxide group, heterocyclic groups, an oxo group and a phosphoryl group. Preferred electron-attracting groups are amido, azo, nitro, fluoroalkyl of 1 to 5 carbon atoms, nitrile, alkoxycarbonyl of 1 to 5 carbon atoms in the alkyl moiety, acyl of 1 to 5 carbon atoms, alkylsulfonyl of 1 to 9 carbon atoms, arylsulfonyl of 6 to 9 carbon atoms, Alkylsulfinyl of 1 to 9 carbon atoms, arylsulfinyl of 6 to 9 carbon atoms, arylcarbonyl of 6 to 9 carbon atoms in the aryl moiety, thiocarbonyl, fluoroalkyl of 1 to 9 carbon atoms, fluoroaryl of 6 to 9 carbon atoms, fluoroalkyl of 3 to 9 carbon atoms, oxo and halogen , More preferred are nitro, fluoroalkyl of 1 to 5 carbon atoms, nitrile, alkoxycarbonyl of 1 to 5 carbon atoms in the alkyl moiety, acyl of 1 to 5 carbon atoms, arylsulfonyl of 6 to 9 carbon atoms, arylcarbonyl of 6 to 9 carbon atoms in the aryl moiety, oxo, and the like Halogen.

specific Examples of the lactone compounds represented by the formula (L-I) or (L-II) are shown below for illustrative purposes only, but not to the limit shown.

A appropriate addition amount of the lactone compound of the formula (L-I) or (L-II) is 0.1 to 50 wt.%, In particular 1 to 30 wt.%, Based on the total solids content the photosensitive layer. An addition of less than 0.1 % is not very effective. An addition of more than 50% leads to a poor imaging performance. Since the lactone compounds of the formulas (L-I) and (L-II), as indicated above, reactive with a developer are, it is desirable that the contact of the photosensitive layer with a development is selective.

The Lactone compounds of formula (L-I) or (L-II) may be either individually or as a mixture of two or more thereof in an arbitrary mixing ratio used as long as the total amount within the above Area lies.

The contains photosensitive layer preferably a thermally decomposable substance having the alkali solubility of alkali-soluble Resin significantly reduced before thermal decomposition. A such substance sharpens the solubility contrast between exposed and unexposed areas. Various onium salts and quinone diazide compounds are as such, thermally decomposable Substance useful. Onium salts are preferred because of their thermal decomposability.

Useful onium salts include diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts and armonium salts. Suitable onium salts include diazonium salts described in SI Schelsinger, Photogr. Sci. Eng., 18, 387 (1974), TS Bal et al., Polymer, 21, 423 (1980) and JP-A-5-158230; Ammonium salts described in U.S. Patents 4,069,055, 4,069,056 and RE 27,992 and Japanese Patent Application No. 2001-140140; Phosphonium salts described in DC Necker et al., Macromolecules, 17, 2468 (1984), CS Wen et al., Tech. Proc. Conf. Curing ASIA, page 478, Tokyo (October 1988), and U.S. Patents 4,069,055 and 4,069,056; Iodonium salts described in JV Crivello et al., Macromolecules, 10 (6), 1307 (1977), Chem. & Eng. News., November 28, page 31 (1988), EP 104 143 U.S. Patents Nos. 339,049 and 410,202, JP-A-2-150848 and JP-A-2-296514; Sulfonium salts as described in JV Crivello et al., Polymer J., 17, 73 (1985), JV Crivello et al., J. Org. Chem., 43, 3055 (1978), WR Watt et al., J. Polymer Sci., Polymer Chem. Ed., 22, 1789 (1984), JV Crivello et al., Polymer Bull., 14, 179 (1985), JV Crivello et al., Macromolecules, 14 (5), 1141 (1981). , JV Crivello et al., J. Polymer Sci., Polymer Chem. Ed., 17, 2877 (1979), EP 370 693 . EP 3 902 114 . EP 233 567 . EP 297 443 . EP 297 442 U.S. Patent Nos. 4,933,377, 161,811, 410,201, 339,049, 4,760,013, 4,734,444 and 2,833,827, and German Patent Specifications Nos. 29 04 626, 36 04 580 and 36 04 581; Selenonium salts described in JV Crivello et al., Macromolecules, 10 (6), 1307 (1977) and JV Crivello et al., J. Polymer Sci., Polymer Chem. Ed., 17, 1047 (1979) ; and arsonium salts described in CS Wen et al., Proc. Conf. Curing ASIA, page 478, Tokyo (October 1988).

From the onium salts are diazonium salts for use in the invention prefers. The diazonium salts described in JP-A-5-158230 are particularly preferred.

counterions the onium salts include a tetrafluoroborate ion, a hexafluorophosphate ion, a triisopropylnaphthalenesulfonate, a 5-nitro-o-toluenesulfonate, a 5-sulfosalicylation, a 2,5-dimethylbenzenesulfonate ion 2,4,6-trimethylbenzenesulfonate, a 2-nitrobenzenesulfonate, a 3-chlorobenzenesulfonate, a 3-bromobenzenesulfonate, a 2-fluoro-caprylnaphthalenesulfonate, a dodecylbenzenesulfonate ion, a 1-naphthol-5-sulfonate ion 2-methoxy-4-hydroxy-5-benzoylbenzenesulfonate ion and a p-toluenesulfonate ion. Among these are a hexafluorophosphate ion and alkylaromatic sulfonate ion, e.g. a triisopropylnaphthalenesulfonate ion and a 2,5-dimethylbenzenesulfonate ion, prefers. A recommended amount of the onium salt is 0.1 to 50% by weight, preferably 0.1 to 30% by weight, more preferably 0.3 to 30 wt.%, Based on the total solids content of the photosensitive Layer.

The Quinone diazide compounds are preferably o-quinone diazide compounds. Orthochinonediazide compounds for use in the invention are suitable have different structures as long as they have at least one o-quinone diazide group and are thermally decomposable to the alkali solubility to increase the photosensitive layer. In thermal decomposition o-Quinone diazide compounds not only lose their inhibitory properties Effect on the resolution of alkali-soluble Resin, but themselves become alkali-soluble, causing them to dissolve light-sensitive layer in an alkali developer support. The o-quinone diazide compounds used in the invention can, include those which are e.g. in J. Kosar, Light-Sensitive Systems, John Wiley & Sons, Inc., pages 339-352. In particular, sulfonates or sulfonamides of o-quinone diazide by reacting with different aromatic polyhydroxy compounds or aromatic amino compounds are obtained, preferably. Also, esters of benzoquinone are (1,2) -diazidosulfonyl chloride or naphthoquinone (1,2) -diazido-5-sulfonyl chloride and a pyrogallol-acetone resin, described in JP-B-43-2840, and esters of benzoquinone (1,2) -diazidosulfonyl chloride or naphthoquinone (1,2) -diazido-5-sulfonyl chloride and a phenol-formaldehyde resin, described in U.S. Patents 3,046,120 and 3,188,210. ester of naphthoquinone (1,2) -diazido-4-sulfonyl chloride and a phenol-formaldehyde resin or a cresol-formaldehyde resin and esters of naphthoquinone (1,2) -diazido-4-sulfonyl chloride and a pyrogallol-acetone resin are also preferable. additional Examples of useful o-quinone diazide compounds are disclosed in U.S. Pat JP-A-47-5303, JP-A-48-63802, JP-A-48-63803, JP-A-48-96575, JP-A-49-38701, JP-A-48-13354, JP-B-41-11222, JP-B-45-9610, JP-B-49-17481, U.S. Patents 2,797,213, 3,454,400, 3,544,323, 3,573,918, 3,674,459 and 3,785 825, British Patents 1 227 602, 1 251 345, 1 267 005, 1 329 888 and 1 330 932 and DE-PS 854 890.

A Recommended addition amount of the o-quinone diazide compound is 1 to 50% by weight, preferably 5 to 30% by weight, more preferably 10 to 30 % By weight, based on the total solids content of the photosensitive Layer. The above-mentioned o-quinone diazide compounds can be either individually or as a mixture of two or more thereof be used. An addition of less than 1% of the o-quinone diazide compound is ineffective at improving imaging performance. A Addition of more than 50% of the o-quinone diazide compound may result in a Reduction of the durability of the image area or reduction lead the sensitivity.

from Point of thermal decomposition are onium salts over the Quinone diazide compounds are preferred. The onium salt with a higher thermal Decomposability will increase the distinction (contrast) between exposed and unexposed Regions of the photosensitive layer considered to be more effective.

The Photosensitive layer provided on the aluminum support can be either a single layer structure or a multilayer structure, which comprises two or more layers. The multilayer structure will be described using a bilayer structure, which is composed of a lower layer and an upper layer, as an example.

At the For planning a bilayer structure, it is preferable to use alkali-soluble resins to make the upper and lower layers so that the alkali-soluble Upper layer resin is less soluble in an alkali developer as that of the lower layer.

Of the Infrared absorber may be attached to any or both of the top and bottom be added to lower layers. The infrared absorbers, which in Different layers can be used the same or different be. Each layer may contain a plurality of infrared absorbers. Independently of which layer the infrared absorber is used in the amount of the infrared absorber in a range of 0.01 to 50 % By weight, preferably 0.1 to 50% by weight, more preferably 0.1 to 30 % By weight, based on the solids content of the layer to which it added becomes. If the infrared absorber incorporated in two or more layers it is preferred that the total amount of the infrared absorber, which are present in the multilayer photosensitive layer is within the range given above.

If the photosensitive layer has a multilayer structure, For example, the thermally decomposable substance described above may be used the alkali solubility of alkali-soluble Resin significantly reduced before the thermal decomposition, to any or both of the upper and lower layers. Because the thermally decomposable substance partly over the However, it is preferred to decompose the time to the lower layer added. If the thermally decomposable substance to two or more layers are added, the to be added to each layer Amount preferably selected so that the total content is within the range specified above.

The Lactone compound may be added to any or both of the top and the bottom be added to lower layers. It is more effective that the lactone compound is added to the upper layer.

(4) Other ingredients:

If desired the photosensitive layer may further contain various additives, as described below, so long as the effects of the present invention are not affected.

Around to increase the distinction between image and non-image areas or scratch resistance It is preferable to improve a polymer of a (meth) acrylate monomer to use two or three perfluoroalkyl groups in its molecule having 3 to 20 carbon atoms, such as the polymer disclosed in JP-A-2000-187318 is described. When the photosensitive layer has a double-layered structure The polymer may be any of the upper or lower ones Layer are added, but the addition to the upper layer stronger effective. The addition amount of the polymer is typically 0.1 to 10% by weight. preferably 0.5 to 5 wt.%, Based on the layer-forming Materials.

In order to improve the scratch resistance, a compound which reduces the static friction coefficient may be added to the photosensitive layer. For example, long-chain alkylcarboxylic acid esters such as those described in US Pat. No. 6,117,913 can be used. While such a compound may be added to any of the upper layer or the lower layer, the addition to the upper layer is more effective. The addition amount of the compound is typically 0.1 to 10 Wt.%, Preferably 0.5 to 5 wt.%, Based on the layer-forming materials.

If required, the photosensitive layer may be a low molecular weight Compound having an acidic group, such as a sulfonic acid group, a carboxylic acid group or a phosphoric acid group, contain. Compounds with a sulfonic acid group, the aromatic sulfonic acids (e.g., p-toluenesulfonic acid and naphthalenesulfonic acid) and aliphatic sulfonic acids are preferred. The connection can be to any layer be added. The addition amount of the compound is typically 0.05 to 5 wt.%, Preferably 0.1 to 3 wt.%, Based on the layering materials. An addition of more than 5% leads to unfavorable increased solubility the layer in a developer.

The Photosensitive layer may include various dissolution suppressors Löslichkeitskontrolle contain. Include suitable dissolution suppressors Disulfone compounds and sulfone compounds such as 4,4'-bishydroxyphenylsulfone, as described in JP-A-11-119418. The dissolution suppressor can be added to each layer. The amount added is typically 0.05 to 20 wt.%, Preferably 0.5 to 10 wt.%, Based on the Layer to which it is added.

Around to increase the sensitivity can a cyclic acid anhydride, a phenolic compound or an organic acid is used in combination become. helpful cyclic acid anhydrides include those described in U.S. Patent 4,115,128, like phthalic anhydride, tetrahydrophthalic anhydride, cis-1,2,3,6-endoxytetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, Chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride and pyromellitic anhydride. helpful Phenolic compounds include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4,4-trihydroxy, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone, 4,4 ', 4' '- trihydroxytriphenylmethane and 4,4', 3 '', 4 '' - tetrahydroxy-3,5,3 ', 5'-tetramethyltriphenylmethane. Useful organic acids include those described in JP-A-60-88942 and JP-A-2-96755 are, like sulfonic acids, sulfinic, alkylsulfuric phosphonic, organophosphate and carboxylic acids. Examples are p-toluenesulfonic acid, dodecylbenzenesulfonic p-toluene sulfinic acid, ethylsulfuric, phenylphosphonic acid, phenylphosphinic Phenylphosphate, diphenylphosphate, benzoic acid, isophthalic acid, adipic acid, p-toluic acid, 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 4-cyclohexane-1,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid and Ascorbic acid. The addition amount of the cyclic acid anhydride, of phenol or organic acid is generally from 0.05 to 20 wt.%, Preferably 0.1 to 15 wt.%, Further preferably 0.1 to 10% by weight, based on the layer-forming materials.

In order to increase the stability of the photosensitive layer under development conditions, the photosensitive layer may include nonionic surfactants (such as those described in JP-A-62-251740 and JP-A-3-208514), amphoteric surfactants (such as those described in U.S. Pat. JP-A-59-121044 and JP-A-4-13149), siloxane compounds (such as those described in U.S. Pat EP 950 517 described) or copolymers of fluorine-containing compounds (such as those described in JP-A-11-288093). These compounds may be added to one or both of the upper and lower layers.

Examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate, Sorbitan trioleate, glycerol monostearate and polyoxyethylene nonylphenyl ether. Examples of the amphoteric surfactants include alkyldi (aminoethyl) glycines, Alkylpolyaminoethylglycine hydrochlorides, 2-alkyl-N-carboxyethyl-N-hydroxyethyl-imidazolinium betaines and N-tetradecyl-N, N-betaines (e.g., Amogen K from Dai-ichi Kogyo Seiyaku Co., Ltd.).

Examples preferred siloxane compounds include trimethylsiloxane / alkylene oxide block copolymers, such as DBE-224, DBE-621, DBE-712, DBP-732 and DBP-534 (all available from Chisso Corp.) and Tego Glide 100 (polyethersiloxane copolymer, available from Tego Chemie Service GmbH).

The Nonionic or amphoteric surfactant may be present in an amount of generally 0.05 to 15 wt.%, Preferably 0.1 to 5 wt.%, Based to the coating composition.

The Photosensitive layer can be an expressing agent to a visible Picture when warming up to disposal to ask, or a colorant, including a dye and a pigment, around a colored image area to disposal to ask.

The printout agent typically includes a combination of a compound that is capable of production an acid upon heating by exposure, namely a photoacid generator, and a salt-forming organic dye. For example, a combination of an o-naphthoquinonediazido-4-sulfonyl halide and a salt-forming organic dye described in JP-A-50-36209 and JP-A-53-8128, and a combination of a trihalomethyl compound and a salt-forming organic dye described in U.S. Pat JP-A-53-36223, JP-A-54-74728, JP-A-60-3626, JP-A-61-143748, JP-A-61-151644 and JP-A-63-58440 , The trihalomethyl compound includes an oxazole compound and a triazine compound, both of which provide a clear printed image with high stability over time.

The dye for image coloring includes the salt-forming organic dyes described above and other dyes. Suitable dyes, including the salt-forming organic dyes include oil-soluble dyes and basic dyes. Specific examples are Oil Yellow # 101, Oil Yellow # 103, Oilpink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, oil black BS and oil black T-505 (all available from Orient Chemical Industries Ltd.), Victoria Pure Blue, Crystal Violet (C.I. 42555), methyl violet (C.I. 42535), ethyl violet, rhodamine B (C.I. 145170B), malachite green (C.I. 42000) and methylene blue (C.I. 52015). The dyes that in JP-A-62-293247 are particularly preferred. The dye is in an amount of generally 0.01 to 10 wt.%, Preferably 0.1 to 3 wt.%, Based on the total solids content of the photosensitive Layer, added.

If the photosensitive layer has a double layer structure, For example, the printout or colorant may be any or all of be added to both the upper and lower layers.

If desired For example, a plasticizer may be added to the photosensitive layer be to the flexibility and the like of the layer to improve. Suitable plasticizers include butyl phthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, Dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, Tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate and Oligomers or polymers of (meth) acrylic acid.

Of the Expression "lower Shift, "he said used here refers to the layer of a variety of layers on the support are provided, closer on the carrier is. According to this definition denotes in the case where a photosensitive Layer on the support is formed of two layers, the term "lower layer" means the lower photosensitive layer Layer. If a layer without imaging function between the photosensitive layer and the carrier is provided, a such non-imaging layer may be referred to as "lower layer". In the first case, if there is no likelihood of confusion, the upper photosensitive Layer sometimes simply as "photosensitive Layer ", while the lower photosensitive layer is sometimes referred to as a "lower layer". The lower layer without imaging function, as in the second Case mentioned can be made from the same constituents except an infrared absorber, as used in the photosensitive layer exist. The proportions of ingredients, except an infrared absorber, in the lower layer, corresponding to those given above Selected areas. To make the lower layer stronger soluble As the upper layer should be designed to lower this Layer to be added amounts of a dissolution inhibitor, a dissolution accelerator and a development sensitivity-enhancing compound be set or additional Additives could be used in this lower layer.

Of the invention Lithographic printing plate precursor is achieved by coating an aluminum support with a coating composition, by dissolving the above ingredients in a suitable solvent is produced. The photosensitive layer and the lower layer can by successively applying the corresponding coating compositions, by dissolving the corresponding components separately prepared in a solvent were on a carrier be generated.

The to be used solvent include, but are not limited to, ethylene dichloride, cyclohexanone, Methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, Dimethoxyethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, Dimethyl sulfoxide, sulfolane, γ-butyrolactone and toluene. These solvents can either used individually or as a mixture thereof.

When a photosensitive coating composition is applied to a previously formed lower layer when the solvent used in the coating composition is capable of dissolving the alkali-soluble resin contained in the lower layer, mixing of the layers at the interface may occur to an extent that is no longer negligible. In extreme cases, the two layers can be mixed to one. If such interfacial mixing occurs from adjacent layers, or if adjacent layers are compatible with each other to behave as a uniform single layer, the effects that should be exerted by the provision of two independent layers could not be achieved. It is therefore desirable that the solvent used to form the photosensitive layer be a poor solvent for the alkali-soluble resin contained in the lower layer.

each Coating composition preferably has a total solids content from 1 to 50% by weight.

When the photosensitive layer is composed of an upper layer and a lower layer, the preferred basis weight of the upper layer is 0.05 to 1.0 g / m ² , and that of the lower layer is 0.3 to 3.0 g / m ² both based on solids, while they can be varied according to use. If the top layer has a basis weight of less than 0.05 g / m ² , the imaging performance may decrease. If the upper layer has a basis weight of more than 1.0 g / m ² , the sensitivity may decrease. The total coating amount of the upper and lower layers is preferably 0.5 to 3.0 g / m ² . A total areal weight of less than 0.5 g / m ² results in deteriorated film properties, and a total areal weight exceeding 3.0 g / m ² tends to result in lowered sensitivity. As the basis weight decreases, the apparent sensitivity increases, but the film properties of the upper and lower layers will deteriorate.

The Upper layer and the photosensitive layer may be through various techniques are applied, such as bar coating, Spin coating, spray coating, Curtain coating, dip coating, roller coating with airbrush, Doctor blade coating and roller blade coating.

The photosensitive coating composition may contain surfactants to improve the coating properties, such as the fluorine-containing Surfactants disclosed in JP-A-62-170950. An appropriate amount of such a surfactant 0.01 to 1 wt.%, In particular 0.05 to 5 wt.%, Based on the Total solids content of the layer to which it is added.

each the coating compositions for the lower layer and the Photosensitive layer is dried after application. The Drying is done on conventional Way, which is known as such performed. For example, the Coating film by a convection heating method, in which hot Air on the carrier applied coating film is blown, a radiation heating method, in which the coating film is dried by heat, the above and below the coated carrier arranged heating plates is emitted (see JP-A-60-149871), or a Konduktionserwärmungsverfahren, in which a coated carrier is brought into contact with a roller which is a heating medium, which circulates herein (see JP-A-60-21334 and JP-A-60-62778), be dried.

The Konvektionserwärmungsverfahren is preferred among these drying methods. To the water content the photosensitive layer is the water content the hot air to be blown preferably 0.007 kg / kg or less, more preferably 0.05 kg / kg or less.

In relating to viability of the printing plate precursor A photosensitive layer tends to be in harsher conditions was dried, for sufficient development, a developer with a higher electrical conductivity to demand.

The means, the harder the drying conditions, the lower the developability the photosensitive layer. Conversely, a photosensitive tends Layer which has been dried under milder conditions, with a developer with a lower electrical conductivity viable to be. In other words, the milder the drying conditions, the higher the developability. The planned drying conditions are set by adjusting the Air temperature, the amount of air, the direction of air flow, the Temperature and the material of a Kontakterwärmungsmedium and the like realized.

For the lower layer, it is preferred that, immediately before being treated with a photosensitive material coated coating composition having as low a residual solvent content as possible, preferably a residual solvent content of not more than 80 mg / m ² , in particular not more than 60 mg / m ² .

(5) aluminum carrier:

The Aluminum plate which can be used in the invention consists from a dimensionally stable, aluminum-based metal, i.e. Aluminum or an aluminum alloy. It just can not a pure aluminum plate, but also a plate from one up Aluminum based alloy that leaves a trace of other elements contains and a plastic film or paper, on which aluminum or a Aluminum alloy is laminated or deposited, can be used. It can also be a composite sheet made of a polyethylene terephthalate film and an aluminum sheet.

in the Following are the various types of substrates mentioned above, comprising aluminum or an aluminum alloy, collectively as Designated aluminum plate. The other elements that are on aluminum based alloy, include silicon, iron, manganese, Copper, magnesium, chromium, zinc, bismuth, nickel and titanium. The total salary the other elements in the aluminum alloy is at most 10% by weight.

A pure aluminum plate is preferred according to the invention. Given the Difficulties in finishing technology while getting Completely Pure aluminum will also contain aluminum, which will leave a trace of contaminating Contains elements do. The invention aluminum plate to be used may be suitable among those in the art known and readily available Materials selected such as JIS A1050, JIS A1100, JIS A3005, JIS A3004 and International Registration Record (AA) 3103A. The aluminum plate can of a Ingots come either by continuous casting or discontinuous casting (DC casting) is produced. A Aluminum plate made by DC casting without process sealing yet Durchtränkungsvertiefungsbehandlung (soaking pit treatment) is also used become. An aluminum plate covered by laminate rollers, transfer and the like textured in the final rolling process is also useful. The invention to be used aluminum plate is about 0.1 to 0.6 mm thick. The Thickness is subject to change according to the size the printing press, the size a printing plate and the wishes of the user.

Of the in lithographic printing plate precursor used aluminum beams is made by (1) graining, (2) Alkali etching and (3) anodizing made. The manufacturing process of the aluminum support an aluminum plate may further comprise additional steps.

(1) Graining:

The Aluminum plate is grained, so that you have a desired surface profile having. The graining involves mechanical graining, chemical grain and electrolytic graining, which is disclosed in JP-A-56-28893; electrochemical graining in an electrolyte solution, the hydrochloric acid or nitric acid contains; and other mechanical graining techniques, like wire brush grains (the aluminum surface is scratched with a metal wire), ball granules with abrasive balls and a polishing agent, and brush grains with a nylon brush and a polish. These graining techniques can either individually or as a combination thereof.

The electrochemical graining in a hydrochloric acid electrolytic solution or a nitric acid electrolytic solution is preferred to prepare the aluminum support for use in the present invention. A suitable current density is 50 to 400 C / dm ² at the anode. More specifically, electrochemical graining is performed, for example, in an electrolytic solution having a hydrochloric acid or nitric acid concentration of 0.1 to 50% by weight at a temperature of 20 to 100 ° C for 1 second to 30 minutes using DC or AC at a current density of 100 to 400 C / dm ² performed. The electrochemical graining is preferable in view of the easiness of fine texturing of the aluminum surface, and thereby the adhesion between the support and the photosensitive layer can be improved.

As a result of the electrochemical graining, crater-like or honeycomb pits having a diameter of about 0.5 to 20 μm can be formed on the aluminum plate in an area ratio of 30 to 100%. The recesses formed contribute to the improvement of the stain resistance of the non-image areas and the press life of the resulting printing plate. For performing electrochemical graining, the amount of current, ie the product of current and time required, is Enough pits to form an important prerequisite. It is desirable from the viewpoint of energy saving to form enough wells with a small amount of current. The surface roughness after graining is preferably 0.2 to 0.5 μm in terms of arithmetic mean roughness (Ra) measured on a section of 0.8 mm over a evaluation length of 3.0 mm in accordance with JIS B0601-1994.

(2) Alkali etching:

The grained Aluminum plate is then chemically etched with an alkali etchant. The Alkali includes, but is not limited to, sodium hydroxide, sodium carbonate, Sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide and lithium hydroxide.

The alkali etching conditions are not particularly limited as long as 0.5 to 4 g / m ^{2 of} aluminum is etched out. In general, the etchant has an alkali concentration of 1 to 50 wt.%, In particular 5 to 30 wt.%, And a temperature of 20 to 100 ° C, in particular 30 to 50 ° C.

To the alkali etching is the aluminum plate acid, like nitric acid, Sulfuric acid, Phosphoric acid, Chromic acid, Hydrofluoric acid or fluoroboric acid cleaned (desmutted). The cleaning after the electrochemical graining becomes preferably carried out with 15 to 65 wt.% Sulfuric acid at 50 to 90 ° C, as it is taught in JP-53-12739.

(3) Anodizing:

The resulting aluminum plate is preferably conventional Anodized to form an anodized film on the aluminum surface. Anodizing is done by applying a direct current or alternating current in an aqueous or non-aqueous solution of sulfuric acid, Phosphoric acid, Chromic acid, oxalic acid, sulfamic, benzenesulfonic etc., or a mixture of two or more of this acid to the Aluminum plate performed.

The electrolyte solution may contain impurity components that are commonly used by an aluminum alloy plate, electrodes, tap water, good Well water etc. and / or additional components. additional Ingredients that may be present include Na, K, Mg, Li, Ca, Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn or the like metals; Cations, e.g. an ammonium ion; and anions, e.g. a nitration, a carbonate ion, a chloride ion, a phosphate ion, a fluoride ion, a sulphite ion, a titanation, a silication and a borate. The additional Ingredients can in a total concentration of up to about 10,000 ppm be.

The anodization conditions vary depending on the type of the electrolyte used. Generally speaking, the electrolyte concentration is 1 to 80% by weight, the liquid temperature is -5 to 70 ° C, the current density is 0.5 to 60 A / dm ² , the voltage is 1 to 100 V, and the electrolysis time is 10 to 200 seconds. The anodization method disclosed in GB Patent No. 1,412,768, in which a high current density is applied in an electrolytic solution with sulfuric acid, is particularly preferable.

A suitable thickness of the anodized film is 1 to 10 g / m ² , preferably 1.5 to 7 g / m ² , more preferably 2 to 5 g / m ² . With an anodized film thickness of less than 1 g / m ² , the aluminum support may easily be scratched. The production of an anodized film of more than 10 g / m ² requires a large electric power, which is economically disadvantageous.

(4) Alkali metal silicate treatment:

If required, the anodized aluminum plate with an aqueous solution an alkali metal silicate soaked. In an illustrative example of the treatment, the aluminum plate in an aqueous 0.01 to 5.0% by weight alkali metal silicate solution at 5 to 40 ° C, preferably 10 to 40 ° C, for 1 to 60 seconds, preferably 2 to 20 seconds, soaked, followed by washing with running water.

The alkali metal silicate includes sodium silicate, potassium silicate and lithium silicate. The aqueous solution of the alkali metal silicate may contain an appropriate amount of sodium hydroxide, potassium hydroxide, lithium hydroxide, etc. The solution may further contain an alkaline earth metal salt or a Group 4 metal salt (Group IVB). The alkaline earth metal salt includes nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate and barium nitrate, sulfates, hydrochlorides, phosphates, acetates, oxalates and borates. The metal salts of the group 4 (Group IVB) include titanium tetrachloride, titanium trichloride, potassium titanium fluoride, potassium titanium oxalate, titanium sulfate, titanium tetraiodide, zirconium dioxide, zirconium oxychloride and zirconium tetrachloride. These Group 4 (Group IVB) alkaline earth metal salts and metal salts may be used either individually or as a combination of two or more thereof.

The amount of silicon adsorbed by the soaking treatment measured by X-ray fluorescence analysis is about 1.0 to 15.0 mg / m ² . The alkali metal silicate treatment is effective to increase the resistance of the aluminum support to an alkali developer. As a result, the washing out of aluminum in the alkali developer is suppressed, and the foaming in a developer due to consumption can be reduced.

Of the invention Lithographic printing plate precursor essentially comprises the aluminum support described above and the photosensitive layer provided thereon. If desired, can a primer layer between the support and the photosensitive one Layer be provided. For producing the primer layer various organic compounds are used, the carboxymethylcellulose, Dextrin, gum arabic, organic phosphonic acids such as amino-containing phosphonic acids (e.g. 2-aminoethylphosphonic acid), substituted or unsubstituted phenylphosphonic acid, naphthylphosphonic acid, alkylphosphonic acids, glycerophosphonic acid, methylenediphosphonic acid and ethylenediphosphonic; organic phosphoric acids, such as substituted or unsubstituted phenylphosphoric acid, naphthylphosphoric acid, alkylphosphoric acid and glycerophosphoric; organic phosphinic acids, such as substituted or unsubstituted phenylphosphinic, naphthylphosphinic, alkylphosphinic and glycerophosphinic; Amino acids, such as glycine and β-alanine; and hydroxyl-containing amine hydrochlorides, such as triethanolamine hydrochloride, include. These organic compounds can be either individual or be used as a mixture of two or more thereof.

worin R¹¹ ein Wasserstoffatom, ein Halogenatom oder eine Alkylgruppe darstellt; R¹² und R¹³ stellen jeweils ein Wasserstoffatom, eine Hydroxylgruppe, ein Halogenatom, eine Alkylgruppe, eine substituierte Alkylgruppe, eine Arylgruppe, eine substituierte Arylgruppe, -OR¹⁴, -COOR¹⁵, -CONHR¹⁶, -COR¹⁷ oder -CN dar, oder R¹² und R¹³ bilden zusammen einen Ring; R¹⁴, R¹⁵, R¹⁶ und R¹⁷ stellen jeweils eine Alkylgruppe oder eine Arylgruppe dar; X stellt ein Wasserstoffatom, ein Metallatom oder NR¹⁸R¹⁹R²⁰R²¹ dar; R¹⁸, R¹⁹, R²⁰ und R²¹ stellen jeweils ein Wasserstoffatom, eine Alkylgruppe, eine substituierte Alkylgruppe, eine Arylgruppe oder eine substituierte Arylgruppe dar, oder R¹⁸ und R¹⁹ bilden zusammen einen Ring; und m stellt eine ganze Zahl von 1 bis 3 dar.A primer layer containing at least one of organic polymers having a repeating unit shown below is also preferable.

wherein R ^{11 represents} a hydrogen atom, a halogen atom or an alkyl group; R ¹² and R ¹³ each represents a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, -OR ¹⁴ , -COOR ¹⁵ , -CONHR ¹⁶ , -COR ¹⁷ or -CN, or R ¹² and R ¹³ together form a ring; R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each represents an alkyl group or an aryl group; X represents a hydrogen atom, a metal atom or NR ¹⁸ R ¹⁹ R ²⁰ R ²¹ ; R ¹⁸ , R ¹⁹ , R ²⁰ and R ²¹ each represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group or a substituted aryl group, or R ¹⁸ and R ¹⁹ together form a ring; and m represents an integer of 1 to 3.

The Primer layer may be prepared by applying a solution of the type described above organic compound in water, an organic solvent (e.g., methanol, ethanol or methyl ethyl ketone) or a mixture hereof on the aluminum support be provided. The solution Can be applied with different application agents and dried to form a primer layer. Alternatively, the aluminum support into the solution immersed to adsorb the compound, followed by washing with Water etc. and drying. Those to be used in the first method solution has a concentration of 0.005 to 10% by weight. The second Method to use solution has a concentration of 0.01 to 20% by weight, preferably 0.05 up to 5% by weight. The second method is by immersing the aluminum support into the solution at 20 to 90 ° C, preferably 25 to 50 ° C, for 0.1 Seconds to 20 minutes, preferably 2 seconds to 1 minute performed. The The solution to be used in the second method can be used with a basic Substance, e.g. Ammonia, triethylamine or potassium hydroxide, or an acidic substance, e.g. Hydrochloric acid or phosphoric acid, on a pH of 1 to 12 can be set. The solution can a yellow dye for improving hue reproducibility of the artwork.

The basis weight of the undercoat layer is suitably 2 to 200 mg / m ² , preferably 5 to 100 mg / m ² . An undercoating layer of less than 2 mg / m ² or more than 200 mg / m ² is used therein say to ensure a sufficient press life.

The thus prepared lithographic printing plate precursors are generally in a stack with an interleaf between each adjacent precursor packed, shipped, transported and stored. In a typical Plant for plate making and printing is a printing plate precursor with an intermediate sheet on it on an automatic loader (auto loader), carried, and mounted in a place where the plate making carried out becomes. Thereafter, the interleaf is removed. If a DTP system is used, is the place of plate production on a press.

After this the intermediate sheet has been removed, the printing plate precursor becomes imagewise exposed and developed.

A The light source used for imagewise exposure is preferred one that has a light emission wavelength in the near-infrared to infrared range has. The exposure can either be a raster exposure or planar exposure. The scanning exposure using a solid-state laser or a semiconductor laser is preferred. A preferred light emission wavelength is 760 to 1,080 nm.

One Developer that can be used to develop the printing plate precursor of the invention, is an alkaline solution with a pH ranging from 9.0 to 14.0, preferably 12.0 to 13.5. The term "developer" as used here is intended to include a replenisher. Known aqueous solutions of alkalis be used as a developer. The alkali agent includes inorganic alkali metal salts, e.g. Sodium silicate, potassium silicate, tertiary sodium phosphate, tertiary potassium phosphate, tertiary Ammonium phosphate, secondary Sodium phosphate, secondary Potassium phosphate, secondary Ammonium phosphate, sodium carbonate, potassium carbonate, ammonium carbonate, Sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, Sodium borate, potassium borate, ammonium borate, sodium hydroxide, ammonium hydroxide, Potassium hydroxide and silicon hydroxide; and organic alkalis, e.g. Monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, Triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, Diisopropanolamine, ethyleneimine, ethylenediimine and pyridine. The watery Solutions of the Alkali agent can either used individually or as a mixture thereof.

Under the above-mentioned aqueous solutions the alkali agent is a so-called silicate developer, the alkali metal silicate as a base or a mixture of a base and a silicon compound (capable of forming an alkali silicate in situ) and a pH of 12 or higher having. Another more preferred is a so-called non-silicate developer, not an alkali silicate, but a non-reducing sugar (an organic compound having a buffer effect) and a base contains.

The development performance of the silicate developer can be adjusted by controlling the concentration of the alkali metal silicate and the ratio of silica (SiO ₂ ) to an alkali metal oxide (M ₂ O) generally expressed as a molar ratio (SiO ₂ ) / (M ₂ O). Examples of suitable silicate developers are an aqueous sodium silicate solution having a molar SiO ₂ / Na ₂ O ratio of 1.0 to 1.5 [dh (SiO ₂ ) / (Na ₂ O) = 1.0 to 1.5] and a SiO _{2 2} content of 1 to 4% by weight (disclosed in JP-A-54-62004) and an aqueous alkali metal silicate solution having a molar (SiO ₂ ) / (M) ratio of 0.5 to 0.75 [ie (SiO ₂ ) / (M ₂ O) = 1.0 to 1.5) and an SiO ₂ content of 1 to 4 wt%, which further comprises potassium in an amount of at least 20%, based on the atomic gram weight of the total alkali metal content of Developer, contains.

The non-silicate developer is more advantageous than the silicate developer for developing the lithographic printing plate precursor of the present invention for the following reasons. The non-silicate developer does not damage the surface of the photosensitive layer and is effective for maintaining a satisfactory ink receptivity on the image area. Considering that a lithographic printing plate material has little freedom of development and tends to undergo a large change in line width with a change in the pH of the developer, the non-silicate developer containing a non-reducing sugar is its buffering effect at the pH Variation, advantageous over a silicate-containing developer. In comparison with a silicate, a non-reducing sugar is less likely to contaminate a conductivity sensor, a pH sensor, etc., used to control developer activity. Furthermore, the non-silicate developer is more effective in improving the discrimination between image and non-image areas. It is believed that this is because the non-silicate developer has a mild behavior in penetrating the photosensitive layer, which is important for achieving the discrimination and the maintenance of the film properties. As a result can a difference between image and non-image areas can be more easily obtained.

Of the non-reducing sugar is a saccharide that does not have free aldehyde or ketone-reducing group and therefore not reducing Owns properties. Non-reducing Sugars are transformed into trehalose-type oligosaccharides, the reducing ones Having groups that are connected to each other, glycosides with a non-sugar unit, which is bonded to the reducing group of a saccharide, and sugar alcohols, which are made by hydrogenating the corresponding reducing sugars are arranged. Any of these groups of non-reducing Sugaring can be suitably used. The non-reducing Sugars described in JP-A-8-305039 are preferred in the present invention used.

The Trehalose-type oligosaccharides include sucrose and trehalose. The glycosides include alkyl glycosides, phenol glycosides and mustard oil glycosides. The sugar alcohols include D, L-arabinotol, ribitol, xylitol, D, L-glucitol, D, L-mannitol, D, L-iditol, D, L-altritol, galactitol and allitol. additionally are also maltitol obtained by hydrogenation of disaccharide maltose, Syrup of reduced sugar obtained by hydrogenation of oligosaccharides and the like are also suitable. Under these non-reducing sugars are trehalose-type oligosaccharides and sugar alcohols are preferred. D-glucitol, sucrose, syrup of reduced sugar, etc. are especially because of their buffering effect in a suitable pH range and their low price is preferred.

The non-reducing sugars can either individually or as a mixture of two or more be used thereof. A preferred non-reducing sugar content in the non-silicate developer is 0.1 to 30% by weight, in particular 1 to 20% by weight. A content of non-reducing sugar of less 0.1% by weight tends to exert no substantial buffering effect. It It is difficult to produce such a highly concentrated solution that diluted use can be to a concentration of non-reducing sugar of more than 30% by weight. In addition, the use of more leads than 30% of the non-reducing sugar at an increased cost.

The to be used in combination with the non-reducing sugar Base is selected from known alkali agents, the inorganic alkali agents and organic alkali agents. The inorganic alkali agents include sodium hydroxide, potassium hydroxide, lithium hydroxide, trisodium phosphate, Tripotassium phosphate, triammonium phosphate, disodium phosphate, dipotassium phosphate, Diammonium phosphate, sodium carbonate, potassium carbonate, ammonium carbonate, Sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, Sodium borate, potassium borate and ammonium borate.

The organic alkalis include monomethylamine, dimethylamine, Trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, Diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, Diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, Ethyleneimine, ethylenediamine and pyridine.

The above indicated bases either individually or as a mixture of two or more be used thereof. Of these, sodium hydroxide and potassium hydroxide prefers.

One Non-silicate developer containing an alkali metal salt of a non-reducing Sugar instead of a combination of a non-reducing sugar and a base, is also useful.

Of the Non-silicate developer may contain an alkaline buffer solution the one weak acid and a strong base in combination with the non-reducing one Sugar includes. The weak acid is preferably one which has a dissociation constant (pKa) of 10.0 to 13.2, e.g. is selected among those in Ionization Constants of Organic Acids in Aqueous Solution, Pergman Press, are described. Specific examples more useful weak acids are alcohols such as 2,2,3,3-tetrafluoropropanol-1, trifluoroethanol and trichloroethanol; Aldehydes such as pyridine-2-aldehyde and pyridine-4-aldehyde; Compounds having a phenolic hydroxyl group, such as salicylic acid, 3-hydroxy-2-naphthonic acid, catechol, gallic acid, sulfosalicylic 3,4-dihydroxysulfonic, 3,4-dihydroxybenzoic acid, Hydroquinone (pKa: 11.56), pyrogallol, o-, m- or p-cresol and resorcinol; Oximes, such as acetoxime, 2-hydroxybenzaldehyde oxime, dimethylglyoxime, Ethanediamide dioxime and acetophenone oxime; in contact with nucleic acid standing substances, such as adenosine, inosine, guanine, cytosine, hypoxanthine and xanthine; Diethylaminomethylphosphonic acid, benzimidazole and barbituric acid.

If desired, various surfactants or organic solvents can be added to the developer and to the replenisher to accelerate or inhibit the development activity, to facilitate the dispersion of development foam, or to increase the ink receptivity of the image area. Anionic, cationic, nonionic or amphoteric surfactants are preferred. If necessary, the developer and the replenisher may contain a reducing agent such as hydroquinone, resorcinol and sodium or potassium salts of inorganic acids such as sulfites and hydrogensulfites; an organic carboxylic acid, a defoaming agent, a water softener, etc. included.

Of the Lithographic printing plate precursor, that has been developed with the developer and the refresher, is a post-treatment with washing water, a rinse solution, the contains a surfactant, or a desensitizing solution, the gum arabic or a starch derivative contains or a combination of such aftertreatments.

On The field of plate making and printing has recently become an automatic developing machine [(plate handler (plate processor)] for Rationalization and standardization spread. A plate handler is generally a development part and a post-treatment part divided and consists of a carrier, treatment solution tanks and spray units together. An exposed plate is developed while it is being processed horizontal on the carrier is transported by successively spraying each sprayed from each treatment solution through a spray nozzle. Recently became proposed a dip development process in which the plate precursor in immersing a holding tank containing a processing solution guided by submerged guide rollers. In these automatic treatment systems, each tank is with filled up with a refresher, as based on throughput, uptime and the like is fixed. A so-called "one-shot processing system", which is a substantially unused process solution used can also be used.

If a lithographic printing plate produced by exposure, development, Washing and / or rinsing and / or Gum is obtained, having an unnecessary image area (i.e., a part corresponding to the original film edges) becomes the unnecessary Image area removed. The removal is preferably carried out by applying a Image remover on the unnecessary Image area and leaving the plate for a prescribed period of time, followed by washing with water, carried out as described in JP-B-2-132293 is taught. A removal method that involves irradiating the unnecessary image area with active beams of light passing through an optical fiber and then developing as disclosed in JP-A-59-174842.

If desired The printing plate thus obtained is treated with a desensitized gum coated before printing. If higher impression capacity is desired, the plate is subjected to a burn-in treatment. It is preferable the pressure plate before baking with a firing conditioner, as described in JP-B-61-2518, JP-B-55-28062, JP-A-62-31859 and JP-A-61-159655 described is to be treated. The treatment with a firing conditioner is applied by applying with a sponge or absorbent Fabric impregnated with a firing conditioner onto the board, or immersing the plate in a jar containing a firing conditioner filled is, or performed by an automatic coating device.

For better Results are the applied burn conditioner with a squeegee or a squeegee roller.

The firing conditioner is usually applied in an amount of 0.03 to 0.8 g / m ² on a dry basis. The applied firing conditioner is then heated as such or heated to a high temperature in a firing treatment after drying (eg, BP-1300, available from Fuji Photo Film Co., Ltd.). The heating is preferably carried out at 180 to 300 ° C for 1 to 20 minutes, which can be changed according to the imaging material.

The fired printing plate can be conventional Treatments according to need, such as washing with water and gumming, to be subjected. If a burn conditioner, the one water-soluble Contains polymer, etc. may be applied to a desensitizing treatment, like gumming, to be dispensed with. The resulting lithographic printing plate is used on an offset printing press to a large number Produce images.

EXAMPLES

The present invention will now be illustrated more specifically with reference to Examples. It should be understood, however, that the invention is not limited thereto. Unless otherwise stated, refer all percentages on the weight.

One aluminum support used in Examples and Comparative Examples prepared as follows.

A 0.3 mm thick aluminum plate (JIS A1050) was degreased with trichlorethylene and grained with a nylon brush and an aqueous pumice slurry (400 mesh). After thoroughly washing with water, the aluminum plate was immersed in a 25% sodium hydroxide aqueous solution at 45 ° C for 9 seconds to etch out about 3 g / m ^{2 of} aluminum, followed by washing with water. After neutralizing by immersion in 20% nitric acid for 20 seconds and washing with water, the plate was anodized in 7% sulfuric acid using direct current at a current density of 15 A / dm ² , 3 g / m ^{2 of} an anodized To produce films. After washing with water and drying, the anodized aluminum plate was treated with an aqueous 2.5% sodium silicate solution at 30 ° C for 10 seconds to prepare an aluminum support. A primer having the following composition was coated at a dry coating thickness of 15 mg / m 2 and dried at 80 ° C for 15 seconds to form a primer layer.

EXAMPLES 1 AND 2 AND COMPARATIVE EXAMPLE 1

A photosensitive layer coating composition having the formulation (A) shown below was coated on the primer layer of the aluminum support and coated in the in 1 was dried under the following conditions to prepare a lithographic printing plate precursor of Example 1. About 10 seconds after the application, high-pressure air of 3,000 mmAq was blown out of slit nozzles onto the wet coating film. The total drying time in the first drying zone ( 3 ) was 15 seconds. The temperature of the hot air leading to the first drying zone ( 3 ) was 80 ° C (velocity: 5 m / s) and the temperature of the high pressure air was 60 ° C (velocity: 200 m / s). In the second drying zone ( 4 ), the total drying time was 20 seconds and the temperature of the hot air was 120 ° C. The dry coating amount of the photosensitive layer thus prepared was 1 g / m ² . The film thickness distribution of the photosensitive layer was measured according to the aforementioned method. As a result, it was found that the relative standard deviation is 15%.

A lithographic printing plate precursor of Example 2 was prepared in the same manner as in Example 1 except that the guide roller (FIG. 14 ) was replaced by a heating roller which had been heated to 100 ° C to carry out heating roller drying for 1.2 seconds. The photosensitive layer thus formed had a basis weight of 1 g / m ² and a thickness distribution with a relative standard deviation of 10%.

For comparison, a lithographic printing plate precursor of Comparative Example 1 was prepared in the same manner as in Example 1 except that the coating film was dried by hot air drying at 100 ° C for 2 minutes (hot air velocity: 2 m / s). The photosensitive layer had a basis weight of 1 g / m ² and a thickness distribution with a relative standard deviation of 30%.

EXAMPLE 3 AND COMPARATIVE EXAMPLE 2

A lithographic printing plate precursor of Example 3 was prepared in the same manner as in Example 2 except that a photosensitive layer-coating composition having the below-described formulation (B) was wire-coated to have a wet basis weight of 1.8 g / m ² to get. The resulting photosensitive layer had a basis weight of 1.3 g / m ² and a thickness distribution with a relative standard deviation of 9%.

For comparison, a lithographic printing plate precursor of Comparative Example 2 was prepared in the same manner as in Example 3 except that drying in hot air (speed: 2 m / sec) was carried out at 100 ° C for 2 minutes. The photosensitive layer thus formed had a basis weight of 1.3 g / m ² and a thickness distribution with a relative standard deviation of 25%.

Synthesis of copolymer (1):

In a 20 ml three-necked flask equipped with a stirrer, a cooling tube and equipped with a dropping funnel were 6.39 g (0.045 mol) of n-propyl methacrylate, 1.29 g (0.015 mol) methacrylic acid and 20 g of 1-methoxy-2-propanol, and the mixture was stirred while at 65 ° C on heated in a hot water bath has been. To the mixture was added 0.15 g of the radical polymerization initiator V-601 (ex Wako Pure Chemical Industries, Ltd.) was added, and the Mixture was for 2 hours at 70 ° C kept while stirred in a stream of nitrogen has been. To the reaction mixture was further added a mixture of 6.39 g (0.045 mol) n-propyl methacrylate, 1.29 g (0.015 mol) methacrylic acid, 20 g of 1-methoxy-2-propanol and 0.15 g of V-601 through the dropping funnel over a 2 hours, followed by stirring at 90 ° C for 2 hours. After completion of the reaction, 40 g of methanol became the reaction mixture added, followed by cooling. The resulting mixture was poured into 2 liters of water with stirring. After pouring was stirring for further Continued for 30 minutes. The precipitate was filtered off and dried to give 15 g of a To obtain copolymer (1) as a white solid. The polystyrene equivalent Mw of the copolymer (1) was 53,000 as measured by gel permeation chromatography.

EXAMPLE 4 AND COMPARATIVE EXAMPLE 3

A lower layer coating composition having the formulation shown below was applied and dried in the same manner as in Example 2. A photosensitive layer coating composition having the formulation (C) shown below was then coated and dried in the same manner as in Example 2 to obtain a lithographic printing plate precursor of Example 4. The double-layered photosensitive layer had a basis weight of 1.2 g / m ² and a thickness distribution with a relative standard deviation of 10%.

For comparison, a lithographic printing plate precursor of Comparative Example 3 was prepared in the same manner as in Example 4 except that two coating films were each dried by drying with hot air at 100 ° C for 2 minutes (hot air velocity: 2 m / s). The double-layered photosensitive layer had a basis weight of 1.2 g / m ² and a thickness distribution with a relative standard deviation of 25%.

Evaluation of lithographic printing plate precursors:

The Lithographic printing plate precursor, obtained in Examples and Comparative Examples in terms of their scratch resistance and their freedom of development in accordance with those described below Test method evaluated. The results obtained are in Table 1 shown. In testing, a developer DT-1, available from Fuji Photo Film, for the photosensitive layers having the formulation (A) or (C) and an alkali developer (A) having the following formulation was for the photosensitive layers are used with the formulation (B).

(a) Scratch resistance:

Of the Printing plate precursor was on a Heidon scratch resistance tester mounted, and the photosensitive layer was coated with a sapphire needle (stylus) (1.0 mm) scratched under increasing load. The plate precursor was then diluted with DT-1 to an electrical conductivity of 45 mS / cm, or developer (A), diluted to electrical conductivity of 75 mS / cm, developed. The needle load, which is a visible Scratches after the development caused, was considered a measure of scratch resistance used. A bigger one Value denotes a higher one Scratch resistance.

(b) Freedom of development:

The printing plate precursor was imaged with Trendsetter, available from Creo, using a test pattern with an exposure energy of 90 mJ / cm ² .

In front the development became the initial one electric conductivity measured by every developer. The exposed plate was with the developed developer. The image density of the unexposed Area (image area) was measured with a reflection densitometer D196, available measured by GretagMacbeth. If the image density is different from the initial one Value reduced by 0.06 or more, became the conductivity of the developer (conductivity after use) in turn. A bigger difference between the initial one conductivity and the conductivity after use means a bigger one Tolerance to developer exhaustion, what indicates that the printing plate precursor a great freedom of development across from a change the developer activity has. The values given in Table 1, in the column "Development Freedom", e.g. 37-55, show that the initial one conductivity 37 mS / cm, and the conductivity after Use was 55 mS / cm.

Out From the results of Table 1, it can be seen that the lithographic printing plate precursors with a narrow thickness distribution of the photosensitive layer (Examples 1 to 4) with respect to the scratch resistance and freedom of development.

Of the invention infrared sensitive lithographic printing plate precursor has a uniform Film thickness on and shows high scratch resistance and outstanding Development freedom.

Claims (12)

A lithographic printing plate precursor comprising: an aluminum support; and a photosensitive layer comprising a water-insoluble and alkali-soluble resin and an infrared absorber, wherein the photosensitive layer has a basis weight of 0.5 to 3 g / m ² and a thickness distribution having a relative standard deviation of 20% or less, wherein the relative standard deviation as described in the description. A lithographic printing plate precursor according to claim 1, wherein the photosensitive layer has a basis weight of 0.7 to 1.5 g / m ² . A lithographic printing plate precursor according to claim 1, wherein the photosensitive layer has a basis weight of 0.7 to 1.2 g / m ² . A lithographic printing plate precursor according to any one of claims 1 to 3, wherein the photosensitive layer has a thickness distribution with a relative standard deviation of 15% or less. A lithographic printing plate precursor according to any one of claims 1 to 3, wherein the photosensitive layer has a thickness distribution with has a relative standard deviation of 10% or less. A lithographic printing plate precursor according to any one of claims 1 to 5, wherein the resin is a polymer having a functional group comprises that of a phenolic hydroxyl group, a sulfonamido group and an active imido group is selected. A lithographic printing plate precursor according to any one of claims 1 to 6, wherein the photosensitive layer further comprises a dissolution inhibitor includes. The lithographic printing plate precursor according to claim 7, wherein the dissolution inhibitor a quaternary ammonium salt or a polyethylene glycol compound. A lithographic printing plate precursor according to any one of claims 1 to 8, wherein the photosensitive layer is one of two or more layers has composite multi-layer structure. The lithographic printing plate precursor according to claim 9, wherein the photosensitive Layer with the multi-layer structure, an upper layer and a comprises lower layer, so that the Aluminum support the lower layer and the upper layer are in this order and the resin contained in the upper layer is less soluble in an alkaline developer than that in the lower one Layer is included. Process for the preparation of a lithographic Printing plate precursor, comprising: Instruct a photosensitive coating solution which is a water-insoluble and alkali-soluble Resin and an infrared absorber comprises, on an aluminum support to form a wet coating film; and Subject to the wet coating film at least one of high pressure air and Hot air, around the lithographic printing plate precursor according to any one of claims 1 to 10 to form. Method according to claim 11, wherein subjecting the wet coating film to at least one from high pressure air and hot air in combination with drying the wet coating film with a heat roller carried out becomes.