JPH11235882A - Laser sensitive lithographic printing plate master - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser sensitive lithographic printing plate master drawable by a laser and having a high ink repellency without desensitizing, a wide control width of a dampening water without IPA of the water and excellent printing durability. SOLUTION: In the lithographic printing plate master comprising a hydrophilic swell layer and a thermosensitive cured layer adjacent at least on a base plate, the cured layer contains (a) a substance for absorbing a light to generate a heat, (b) a compound having an ethylenic unsaturated group, (c) a compound having a thiol group, and (d) a substance for generating a radial by heating. And, the substance for absorbing the light to generate the heat has an absorption in a wavelength band of 700 to 1,100 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing plate precursor. More specifically, in a plate making process, digitally processed image information can be drawn by using a laser, and in a printing process, it is insensitive. The present invention relates to a novel laser-sensitive lithographic printing plate precursor that has high ink repellency without performing a grease treatment, has a wide control range of dampening solution, and can eliminate IPA (isopropanol) without dampening solution. .

[0002]

2. Description of the Related Art Conventionally, as a plate to be subjected to lithographic printing, a lipophilic photosensitive layer is applied on an aluminum substrate which has been subjected to a hydrophilic treatment, and the photosensitive layer is left in the image area by a photolithography technique. In the non-image area, the surface of the aluminum substrate is exposed, and a dampening water layer is formed on the surface to repel the ink. Instead, a waterless PS plate using a silicone rubber layer as an ink repellent layer, a so-called waterless lithographic plate, is known.

The PS plate with water is a printing plate excellent in practical use. The substrate is usually made of a grained aluminum substrate and, if necessary, is subjected to a treatment such as anodizing the surface of the grain. In addition, the water retention of the dampening solution is improved, and the adhesion to the photosensitive layer is reinforced. Also, in order to obtain the storage stability of the photosensitive layer, the surface of the aluminum substrate is generally subjected to a chemical treatment with zirconium fluoride, sodium silicate or the like.

The PS plate with water is widely used because of its excellent printing characteristics such as printing durability and image reproducibility. On the other hand, the PS plate with water has such a complicated manufacturing process,
Simplification is desired.

JP-A-5-19460 discloses a lithographic printing plate comprising an inorganic porous material such as polyvinyl alcohol, a crosslinking agent and titanium oxide. This printing plate compensates for the lack of water holding power of polyvinyl alcohol by containing a large amount of inorganic porous material such as titanium oxide, but the layer itself is hard and cannot substantially swell, so the ink repellency is not necessarily It was not good and the printing durability was poor.

On the other hand, lithographic printing plates provided with a hydrophilic swelling layer have been proposed, for example, in JP-A-8-282142, JP-A-8-282144 and JP-A-8-292558. . Since this lithographic printing plate is provided with a hydrophilic swelling layer that swells in a high ratio with respect to water and can store water in the layer, it exhibits high ink repellency without desensitizing treatment, It has the feature that the control range of the fountain solution is wide and the IPA-free fountain solution can be used.

[0007] As a simple form of the PS plate with water,
Provide an image receiving layer such as toner on a support such as paper,
A direct-drawing lithographic printing plate precursor that forms an image using electrophotographic technology, desensitizes non-image areas with an etchant, etc., and converts the image receiving layer to an ink repellent layer for use is widely used. I have. Specifically, an image-receiving layer comprising a water-soluble binder polymer, an inorganic pigment, a water-proofing agent and the like is generally provided on a water-resistant support. For example, US Pat.
No. 65, JP-B-40-23581, JP-A-48-9802, JP-A-57-205196, JP-A-60-2309, JP-A-57-179
No. 1, JP-A-57-15998, JP-A-57-15998
-96900, JP-A-57-205196, JP-A-63-166590, JP-A-63-1
No. 66591, JP-A-63-317388,
JP-A-1-114488, JP-A-4-36786
No. 8 has been proposed. These direct-drawing lithographic printing plate precursors include PVA, starch, hydroxyethylcellulose, casein, gelatin, polyvinylpyrrolidone, and vinyl acetate as an image receiving layer to be converted into an ink repellent layer.
Water-dispersible polymers such as crotonic acid copolymers, styrene-maleic acid copolymers and other water-soluble binder polymers and acrylic resin emulsions that exhibit hydrophilicity before desensitization treatment, silica, calcium carbonate, etc. A composition comprising such an inorganic pigment and a waterproofing agent such as a melamine-formaldehyde resin condensate has been proposed. In order to convert the image receiving layer into an ink repellent layer, the direct drawing type lithographic printing plate requires desensitization treatment, and shows no ink repellency without the treatment. Special agents had to be used as fountain solution.

[0008] These PS plates are made into a printing plate through a plate making process by photolithography techniques such as exposure and development through an original film or the like. In recent years, as an alternative technique, a laser has been used without using an original film. There has been proposed a laser-sensitive lithographic printing plate for directly drawing image information digitally processed on a plate surface.

As a method for making a PS plate with water that requires dampening water into a laser-sensitive type, there have been many proposals of a type in which direct drawing is performed using a high-sensitivity photopolymer sensitive to a He-Ne or Ar laser. However, because of their high sensitivity, plate materials could not be handled in a light room, and a large-scale and expensive automatic exposure and development plate-making apparatus was required. On the other hand, as a method of making a waterless lithographic printing plate a laser-sensitive type, for example, DE-A 2512038 discloses that a lipophilic surface is supported or a nitrocellulose and a carbon black are contained on a support having carbon black. After forming an image using a laser using a heat mode recording material in which a layer and an uncured silicone layer are laminated, the silicone layer in the exposed portion is dissolved using a solvent such as naphtha, and the silicone layer in the other portion is dissolved. A method of curing is proposed. However, in this method, it is difficult to handle a plate material during plate making, a curing step of a silicone layer is required in a development step, and the use of an organic solvent is indispensable from the viewpoint of environmental problems. Was something.

[0010] Also, FR-A1473751 discloses that
A heat mode recording material using a layer having nitrocellulose, carbon black, and silicone on a substrate having a lipophilic surface has been proposed. After forming an image using a laser, the image forming portion becomes lipophilic. Is converted to However, this method has a poor ink-adhesive property because the silicone in the ink-impregnated portion is not removed from the plate surface.

Further, US Pat. No. 5,379,698 discloses a heat-mode waterless planographic printing plate using a metal thin film as a heat-sensitive layer. This print version
Although the heat-sensitive layer is quite thin, a sharp image can be obtained, which is advantageous in terms of the resolution of the printing plate.However, the adhesion between the substrate and the heat-sensitive layer is poor, and the heat-sensitive layer in the non-image area peels off during printing. There is a problem that ink adheres and becomes a defect on printed matter.

Also, US Pat. No. 5,353,705 proposes a heat mode recording material in which polyvinyl alcohol is laminated as an ink repellent layer on a laser sensitive layer composed of nitrocellulose and carbon black. However, the ink repellency was extremely insufficient even under a dampening water supply.

[0013]

DISCLOSURE OF THE INVENTION The present inventors can directly draw image information digitally processed by using a laser on a printing plate, and control the dampening solution during printing more than the conventional PS plate with water. Laser-sensitive lithographic printing with a wide width, IPA-free fountain solution, high ink repulsion without going through complicated plate-making processes such as desensitization treatment, and excellent printing durability We have been working diligently to develop plate precursors, and the intended purpose of lithographic printing plates with at least a hydrophilic swelling layer and a laser-sensitive thermosetting layer on the substrate is to be achieved by using a specific compound for the thermosetting layer. The inventor has found that this is achievable and arrived at the present invention.

An object of the present invention is to enable digitally processed image information to be drawn using a laser in a plate making process, and to provide high ink repellency without performing desensitization in a printing process. The control range of the dampening solution is wide, and IPA (isopropanol) of the dampening solution
Another object of the present invention is to provide a novel laser-sensitive lithographic printing plate precursor that can be made less pressurized.

[0015]

SUMMARY OF THE INVENTION The present invention aims to achieve the above object, and a laser-sensitive lithographic printing plate precursor according to the present invention has the following constitution.

(1) A lithographic printing plate precursor comprising at least a hydrophilic swelling layer and a thermosetting layer adjacent to each other on a substrate,
The heat-sensitive layer comprises: (a) a substance that absorbs light and generates heat; (b)
A laser-sensitive lithographic printing plate precursor comprising: a compound having an ethylenically unsaturated group; (c) a compound having a thiol group; and (d) a substance that generates a radical by heating.

(2) The laser according to (1), wherein the compound (b) containing an ethylenically unsaturated group is a compound having two or more ethylenically unsaturated groups in one molecule. Sensitive lithographic printing plate precursor.

(3) The laser-sensitive lithographic plate as described in (1) or (2) above, wherein the compound having a thiol group (c) is a compound having two or more thiol groups in one molecule. Printing plate original.

(4) The above (1) to (3), wherein the thermosetting layer contains (f) an epoxy compound.
The described laser-sensitive lithographic printing plate precursor.

(5) The laser-sensitive lithographic printing plate precursor as described in (1) to (4), wherein the compound (b) having an ethylenically unsaturated group further has a hydroxyl group.

(6) The laser-sensitive lithographic printing plate precursor as described in any of (1) to (5) above, wherein the thermosetting layer contains (e) a substance which generates an acid upon heating.

(7) The laser-sensitive lithographic plate as described in (1) to (6) above, wherein the substance (a) that absorbs light and generates heat has absorption in a wavelength range of 700 to 1100 nm. Printing plate original.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A lithographic printing plate obtained from the lithographic printing plate precursor of the present invention has high ink repellency without performing desensitization treatment, has a wide control range of dampening solution,
This is a lithographic printing plate which can be printed with a fountain solution without using IPA or the like and which can form an image with a laser and has excellent printing durability.

The lithographic printing plate obtained from the printing plate precursor of the present invention has such excellent characteristics because of the presence of a hydrophilic swelling layer which can swell at a high water swelling ratio, and heat-curing by laser irradiation. This is considered to be due to the fact that the layer strongly adheres to the hydrophilic swelling layer to form a strong image portion.

Although the detailed reasoning is not always clear, the polymer containing a high proportion of water has high oil-based ink repellency per se and is stable on the surface even in a very thin dampening water layer. It is presumed that it has high ink repellency without desensitizing treatment, has a wide control range of dampening solution, and can be printed with dampening solution without using IPA. You. Further, the non-image area and the image area of a lithographic printing plate having a hydrophilic swelling layer are repeatedly subjected to pressure or ink peeling force during printing, but such a hydrophilic swelling layer swollen at a high water swelling ratio is used. The non-image area is excellent in printing durability in order to disperse and absorb a strong force.

An image is formed on the hydrophilic swelling layer which swells at such a high ratio with the aid of laser light, and the heat-sensitive cured layer made of a specific substance is adhered to the hydrophilic swelling layer. It is presumed that the cured heat-sensitive cured layer develops printing durability that can withstand the pressure of hundreds of thousands of times and the peeling force of the ink during printing as an ink deposition layer.

First, the thermosetting layer of the present invention will be described.

The thermosetting layer of the present invention comprises (a) a substance that absorbs light and generates heat, (b) a compound having an ethylenically unsaturated group, (c) a compound having a thiol group, and (d)
Contains a substance that generates radicals by heating as an essential component.

Since the lithographic printing plate precursor according to the present invention forms an image by irradiating a laser beam, the compound (a) that absorbs light and generates heat may be any compound that absorbs laser beam. Any substance can be used. The wavelength of the laser light used during plate making of the printing plate of the present invention can be used in any region of the ultraviolet, visible, and infrared regions, but has an absorption region that matches the wavelength of the laser light used. It is necessary to use a substance that absorbs light and generates heat. Among these, the laser light used in the present invention is preferably a laser light having a wavelength in the infrared region.

Therefore, it can be said that a compound having an absorption region in the infrared region is preferable as the substance that absorbs light and generates heat according to the present invention. Specifically, the maximum absorption wavelength is preferably 7
Cyanine dye, azurenium dye, squarylium dye, croconium dye, azo disperse dye, bisazostilbene dye, naphthoquinone dye, quinone imine dye, quinone diimine dye, methine dye in the range of 00 nm to 1100 nm , Trisazo dye,
Pyrylium dye, aminium dye, coumarin dye, anthraquinone dye, perylene dye, phthalocyanine dye, naphthalocyanine metal complex dye, dithiol nickel complex dye, indoaniline metal complex dye, intermolecular CT dye, benzothiopyran spiropyran And infrared or near infrared absorbing dyes.

Further, black dyes such as Acid First Black, Acid Black, Direct Black, Azoic Black, Bat Black, Disperse Black, Solvent Black, Reactive Black, and Chrome Black as referred to by the color index name are also included.

The dyes are roughly classified into acid dyes, basic dyes, direct dyes, disperse dyes, reactive dyes, oil-soluble dyes and the like according to their dyeing modes, and any of them may be used. In this case, the dye is preferably a black dye. Preferred black dyes include acid dyes and basic dyes. As acid dyes, metal complex azo dyes such as chromium, copper, and cobalt, and as basic dyes, polymethine dyes having an amino group or a substituted amino group such as a quaternary ammonium salt, azo dyes, azomethine dyes, and anthraquinone A system dye, a triphenylmethane dye and the like are particularly preferable.

Of these black dyes, nigrosine dyes can be preferably used. Specific examples of these nigrosine dyes include those described as CISolvent Black 7, specifically, Nigrosine Base; N (Natio
nal Aniline Div.Alliee Chemical & Dry Corp), Ni
grosine BaseNB (manufactured by Williams Ltd.), Nigrosine BaseGB
(Farbenfabriken Bayer AG), Nigrosine BaseLK (Ba
dische Anilin & SodaFabrik AG), CIAcid Black
OrientNigrosin marked as 2
e BR, OZ (Orient Chemical Co., Ltd.), Nigrosine Ba
se NB conc (Sumitomo Chemical Co., Ltd.), Nigrosine WLA (Fa
rbenfabriken Bayer AG).

Specific examples of the metal complex salt type azo dyes include Aizen spiron black BNH, MH, RLH, BH
And specific examples of the basic dye include Eizenkatilon black SBH, BXH, SH, NH, MH, AWH,
KBH (all above, Hodogaya Chemical Industry Co., Ltd.) and the like.

As a pigment, a black pigment is preferable.
Specific examples thereof include carbon black, aniline black, iron black, titanium black, and a pigment resin color (pigment resin printing agent) in which a pigment and a resin are mixed and dispersed. Carbon black is roughly classified into gas black, acetylene black and oil black depending on its raw material, and is roughly classified into channel black, furnace black, acetylene black and the like according to the production method, and any of them can be used. Pigment resin colors include water-in-oil type (W / O type) and oil-in-water type (O / W type)
Are roughly divided into The W / O type comprises a paste in oil in which a pigment is dispersed in a solvent solution of a resin and a W / O type emulsion (extender) as a diluent. On the other hand, O /
The W type is a color base in which a pigment is dispersed in water with a surfactant (dispersant) and a stabilizer, and an O / W resin emulsion (binder) for fixing the pigment to a non-colored material. And O / W emulsion for imparting the same. Any pigment resin color is not particularly limited.

Of these light-to-heat conversion materials, which are also preferred compounds such as metal powders such as titanium, infrared or near-infrared absorbing dyes, black dyes and black pigments are preferably used.

In the present invention, the proportion of the substance (a) which absorbs light and generates heat in the heat-sensitive cured layer is preferably 3 to 70% by weight, more preferably 5 to 50% by weight on a solid basis. If it exceeds 70% by weight, the original function of each layer is significantly reduced, and if the proportion of the black substance is less than 3% by weight, the laser sensitivity is insufficient.

Next, the compound (b) having an ethylenically unsaturated group of the present invention is not particularly limited as long as it is a compound having an ethylenically unsaturated group in a molecule. Alternatively, a compound having a methacryloyl group, a vinyl group, or an allyl group is preferable. As the compound having an ethylenically unsaturated group, a compound having two or more ethylenically unsaturated groups in one molecule is preferably used.

As the compound having two or more ethylenically unsaturated groups in one molecule, all known compounds can be used. Particularly preferred compounds are those having two acryloyl groups or two methacryloyl groups in one molecule. These are compounds having the above, and specific examples thereof include the following. Hereinafter, “□□□□ (meth) acrylate” means □□□□ acrylate and □□□□ methacrylate.

(I) Esterified product of a compound having two or more hydroxyl groups in one molecule and acrylic acid or methacrylic acid: Specific examples of the compound having two or more hydroxyl groups in one molecule include ethylene glycol, diethylene glycol, Triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol,
Dipropylene glycol, polypropylene glycol,
1,3-butanediol, 1,4-butanediol,
1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 2-butene-1,4-diol, 5-hexene-
1,2-diol, 7-octene-1,2-diol,
3-mercapto-1,2-propanediol, hydroquinone, dihydroxyanthraquinone, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, bisphenol A, bisphenol S, phenol formaldehyde novolak resin, resole resin, resorcinbenzaldehyde resin,
Pyrogallol acetone resin, hydroxystyrene polymer and copolymer, glycerin, diglycerin, trimethylolpropane, 1,2,4-butanetriol, pentaerythritol, dipentaerythritol, sorbitol, sorbitan, polyvinyl alcohol, cellulose and derivatives thereof And hydroxyethyl (meth) acrylate polymers and copolymers.

The compound having two or more hydroxyl groups in one molecule and acrylic acid or methacrylic acid can be esterified by a known method to obtain a desired (meth) acrylate compound.

(R) Reacted product of an epoxy compound having two or more epoxy groups in one molecule and acrylic acid or methacrylic acid: As an epoxy compound that can be preferably used in the heat-sensitive layer of the present invention, a hydroxyl group is used in one molecule. Epoxy compounds obtained by reacting epihalohydrin with a compound having two or more compounds are exemplified.

The desired (meth) acrylate compound can be obtained by reacting these epoxy compounds with acrylic acid or methacrylic acid by a known method.

(A) Reaction product of a compound having two or more amino groups in one molecule and glycidyl (meth) acrylate: A compound having two or more amino groups in one molecule is represented by the following general formula (1) The polyamine shown by these is mentioned.

R ¹ HN-A-NHR ² (1) (wherein R ¹ and R ² are a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted phenyl group, A substituted or unsubstituted aralkyl group, which may be the same or different, and examples of the substituent include an alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, and an aryl group. , Hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, hydroxymethyl group, hydroxypropyl group, chloromethyl group, bromomethyl group, phenyl group, p-hydroxyphenyl Group, p
-Bromophenyl group, p-tolyl group, o-tolyl group, benzyl group and the like. A represents a divalent linking group, and is specifically represented by-(A1) p- (A2) q-. Where A1 Is a substituted or unsubstituted cyclic or acyclic alkylene having 1 to 20 carbon atoms, a substituted or unsubstituted phenylene, and the substituent is an alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, an aryl group. And the like. A2 is -OB1-, -SB2-, -NH-B3
-, -CO-O-B4-, -SO2-NH-B5-,
1, B2, B3, B4 and B5 are the same as A1 described above. p represents an integer of 1 or more, and q represents 0 or an integer of 1 or more. Specific examples of the divalent or higher valent amino compound represented by the general formula (1) include dioxyethylene diamine, trioxyethylene diamine, tetraoxyethylene diamine, pentaoxyethylene diamine, hexaoxyethylene diamine, peptaoxyethylene diamine, octaoxyethylene diamine, Nonaoxyethylenediamine, decaoxyethylenediamine, tritriacontaoxyethylenediamine, monooxypropylenediamine, dioxypropylenediamine, trioxypropylenediamine,
Tetraoxyethylenediamine, pentaoxypropylenediamine, hexaoxypropylenediamine, heptaoxypropylenediamine, octaoxypropylenediamine, nonaoxypropylenediamine, decaoxypropylenediamine, tritriacontaoxypropylenediamine, polymethylenediamine, polyetherdiamine, diethylenetriamine Aliphatic polyamine compounds such as iminobispropylamine, bis (hexamethylene) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dimethylaminopropylamine, diethylaminopropylamine, substituted polyamine, and m-xylylene diamine Aliphatic polyamine compounds having an aromatic ring such as amines and tetrachloro-p-xylylenediamine , Menthane diamine, N- aminoethylpiperazine, 1,3-diaminocyclohexane,
Alicyclic polyamines such as isophorone diamine, m-phenylenediamine, diaminodiphenyl ether, 4,4 ′
-Methylene dianiline, diamino diphenyl sulfone,
Benzidine, 4,4′-bis (o-toluidine), 4,
4'-thiodianiline, o-phenylenediamine, dianisidine, methylenebis (o-chloroaniline), 2,
4-toluenediamine, bis (3,4-diaminophenyl) sulfone, diaminoditrisulfone, 4-chloro-
o-phenylenediamine, 4-methoxy-6-methyl-
Examples include aromatic polyamine compounds such as m-phenylenediamine and m-aminobenzylamine, dicyandiamide, and adipic dihydrazide.

Further, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-ethylimidazole, 2,4-dimethylimidazole and the like are also examples of preferred amino compounds. Further, polyamidoamine obtained by reacting the above-mentioned polyamine and carboxylic acid so that both terminals become amino groups can also be mentioned.

The compound having two or more amino groups in one molecule and glycidyl (meth) acrylate can be reacted by a known method to obtain a desired (meth) acrylate compound.

(Ii) A reaction product of a compound having two or more amino groups in one molecule with acrylic acid or methacrylic acid: a compound having two or more amino groups in one molecule and acrylic acid or methacrylic acid as described in the preceding section. The desired (meth) acrylate compound can be obtained by reacting the acid by a known method.

(V) Reaction product of a compound having two or more carboxyl groups in one molecule and glycidyl (meth) acrylate: Specific examples of the compound having two or more carboxyl groups in one molecule are as follows. However, the present invention is not limited to these.

Malonic acid, succinic acid, malic acid, thiomalic acid, racemic acid, citric acid, glutaric acid, adipic acid,
Pimelic acid, spearic acid, azelaic acid, sebacic acid,
Divalent organic carboxylic acids such as maleic acid, fumaric acid, itaconic acid and dimer acid; trivalent organic carboxylic acids such as trimellitic acid; and 3,9-bis (2-carboxyalkyl)
2,4,8,10-tetraoxaspiroundoundane and the like.

Further, carboxy-modified unvulcanized rubber can be used. Specifically, it is a carboxy-modified product of natural rubber, butadiene, isoprene, styrene, acrylonitrile, acrylate, or a homopolymer or copolymer selected from the group consisting of, for example, carboxy-modified polybutadiene and carboxy-modified styrene-butadiene copolymer. And carboxy-modified acrylonitrile-butadiene copolymer and carboxy-modified methyl methacrylate-butadiene copolymer.

Further, a compound obtained by subjecting the above polycarboxylic acid to an esterification reaction with polyethylene glycol or polypropylene glycol can also be used. These compounds preferably have carboxyl groups at both ends.

A compound having two or more carboxyl groups in one molecule and glycidyl (meth) acrylate are
The desired (meth) is obtained by reacting in a known manner.
An acrylate compound can be obtained.

(F) Esterified product of a compound having two or more carboxyl groups in one molecule and hydroxy (meth) acrylate: As the compound having two or more carboxyl groups in one molecule, the compound described in the preceding section can be used. Can be mentioned. The compound having two or more carboxyl groups in one molecule and hydroxy (meth) acrylate can be reacted by a known method to obtain a desired (meth) acrylate compound.

Of these, the (meth) acrylate compound preferably has a hydroxyl group from the viewpoint of the adhesiveness between the hydrophilic swelling layer and the heat-sensitive layer.
(R), (H) and (H) are preferably (meth) acrylate compounds.

Further, as the compound having two or more ethylenically unsaturated groups in one molecule, the following compounds can be preferably used in addition to the above-mentioned compounds.

(A) Allyl urethanes: products obtained by the addition reaction of a polyvalent isocyanate and an allyl alcohol such that two or more allyl groups are present in one molecule.

The following are examples of the polyvalent isocyanate, but the present invention is not limited thereto.
Paraphenylene diisocyanate, 2,4- or 2,
6-toluylene diisocyanate (TDI), 4,4-
Diphenylmethane diisocyanate (MDI), tolidine diisocyanate (TODI), xylylene diisocyanate (XDI), hydrogenated xylylene diisocyanate, cyclohexane diisocyanate, metaxylylene diisocyanate (MXDI), hexamethylene diisocyanate (HDI or HMDI), lysine diisocyanate (LDI) (Also known as 2,6-diisocyanatomethylcaproate), hydrogenated MDI (H12MDI)
(Alias 4,4'-methylenebis (cyclohexyl isocyanate)), hydrogenated TDI (HTDI) (alias methylcyclohexane 2,4 (2,6) diisocyanate),
Hydrogenated XDI (H6XDI) (also known as 1,3- (isocyanatomethyl) cyclohexane), isophorone diisocyanate (IPDI), diphenyl ether isocyanate, trimethylhexamethylene diisocyanate (T
MDI), tetramethylxylylene diisocyanate,
Polymethylene polyphenyl isocyanate, dimer acid diisocyanate (DDI), triphenylmethane triisocyanate, tris (isocyanate phenyl) thiophosphate, tetramethyl xylylene diisocyanate, lysine ester triisocyanate, 1, 6,
11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,
Examples include 3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, and polymers of polyisocyanates.

Alternatively, a compound obtained by reacting the isocyanate compound and the polyol in such a ratio that the isocyanate group remains can also be used as the isocyanate compound. Examples of the polyol that can be used in this case include the polyols described in the preceding section.

(B) Allyl esters: Products obtained by subjecting a polyvalent carboxylic acid or its anhydride to an allyl alcohol to an esterification reaction such that two or more allyl groups are present in one molecule. The polyhydric carboxylic acid and allyl alcohol are esterified by a known method to obtain a desired allyl ester.

Specific examples of the polycarboxylic acid used at this time include malonic acid, succinic acid, malic acid, racemic acid,
Divalent carboxylic acids such as citric acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, itaconic acid and dimer acid, and trivalent carboxylic acids such as trimellitic acid , 3,9-bis (2-carboxyalkyl) -2,4,8,10-tetraoxaspiroundecane and the like.

Further, carboxy-modified unvulcanized rubber can be used. Specifically, natural rubber, butadiene,
Isoprene, styrene, acrylonitrile, carboxy-modified homopolymer or copolymer selected from acrylates, such as carboxy-modified polybutadiene, carboxy-modified styrene-butadiene copolymer,
Examples thereof include carboxy-modified acrylonitrile-butadiene copolymer and carboxy-modified methyl methacrylate-butadiene copolymer.

Specific examples of the acid anhydride include acetic anhydride, propionic anhydride, butyric anhydride, maleic anhydride, citraconic anhydride, crotonic anhydride, phthalic anhydride and the like.

(C) Vinyl ethers: products obtained by adding two or more vinyl groups to one molecule by an addition reaction between polyol and acetylene or an ether exchange reaction between polyol and vinyl ether. In this case, the polyol described in the preceding section can be used as the polyol. These polyols can be subjected to an addition reaction with acetylene by a known method to obtain desired vinyl ethers.

The desired vinyl ethers can also be obtained by subjecting the polyol to a transesterification reaction with methyl vinyl ether or ethyl vinyl ether by a known method.

Specific examples of vinyl ethers include dipropylene glycol divinyl ether, triethylene glycol divinyl ether, and m-phenylenebis (ethylene glycol) divinyl ether.
The present invention is not limited to these.

These compounds having two or more ethylenically unsaturated groups in one molecule may be used alone or in combination of two or more.

Among these compounds having two or more ethylenically unsaturated groups in one molecule, allyl urethanes for the purpose of imparting flexibility to the photosensitive layer and improving the printing durability of the printing plate,
Urethane acrylate is preferable, and it is more preferable to use epoxy acrylate in combination from the viewpoint of adhesion to the hydrophilic swelling layer.

The proportion of the compound having an ethylenically unsaturated group (b) in the heat-sensitive cured layer in the present invention is preferably from 5 to 70% by weight, more preferably from 1 to 70% by weight on a solids basis.
0 to 80% by weight. If it exceeds 80% by weight, the original function of each layer is significantly reduced, and if it is less than 5% by weight, the laser sensitivity is insufficient. Next, (c) the compound having a thiol group used in the thermosetting layer of the present invention will be described. The compound having a thiol group is not particularly limited as long as it has at least one thiol group in one molecule, but it is preferable to use a compound having two or more thiol groups in one molecule.

As the compound having two or more thiol groups in one molecule, known dithiols and polythiols can be used. Specific examples of more preferable compounds include the following.

(1) Dithiols having an aliphatic hydrocarbon as a main chain: methanedithiol, ethanedithiol, propanedithiol, butanedithiol, heptanedithiol, hexanedithiol, octanedithiol, nonanedithiol, decanedithiol, undecanedithiol, dodecanedithiol , Tridecanedithiol, tetradecanedithiol, heptadecanedithiol, hexadecanedithiol, octadecanedithiol, 4,8-
Dithiaundecane-1,11-dithiol, bis (2-
Mercaptoethyl) sulfide, 1,3-dihydroxy-2-propyl-2 ', 3'-dimercaptopropylether, 2,3-dihydroxypropyl-2', 3'-
Dimercaptopropyl ether, 2,6-dimethyloctane-2,6-dithiol, 2,6-dimethyloctane-3,7-dithiol, 3,3, -dimethylbutane-
2,2-dithiol, 2,2-dimethylpropane-1,
3-dithiol, 3,4-dimethoxybutane-1,2-
Dithiol, 3,4-dimercaptobutanol, 2,3
-Dimercapto-1-propanol, 1,3-dimercapto-2-propanol, 1,2-dimercapto-1,
3-butanediol, 1,2-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl-2 ', 3'-
Dimethoxypropyl ether, 3,5,5-trimethylhexane-1,1-dithiol, 3,4,5-trimethoxypentane-1,2-dithiol, neopentanetetrathiol, bis (11-mercaptoundecyl) sulfide, Bis (2-mercaptoethyl) sulfide, bis (18-mercaptooctadecyl) sulfide, bis (8-mercaptooctyl) sulfide, bis (10-
Mercaptodecyl) sulfide, bis (12-mercaptodecyl) sulfide, bis (9-mercaptononyl)
Sulfide, bis (4-mercaptobutyl) sulfide, bis (3-mercaptopropyl) sulfide, bis (6-mercaptohexyl) sulfide, bis (7-mercaptoheptyl) sulfide, bis (5-mercaptopentyl) sulfide, 2,2 -Bis (mercaptomethyl) -1,3-propanedithiol.

(2) Dithiols having an aromatic or heterocyclic ring as a main chain: 9,10-anthracenedimethanethiol;
1,3-diphenylpropane-2,2-dithiol,
2,4-dimethylbenzene-1,3-dithiol, 4,
5-dimethylbenzene-1,3-dithiol, 4,4 ′
-Dimercaptobiphenyl, 4,4'-dimercaptobibenzyl, 2,4-di (p-mercaptophenyl) pentane, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,4-naphthalenedityl, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol,
2,7-naphthalenedithiol, 1,1, -bis (mercaptomethyl) cyclohexane, phenylmethane-1,
1-dithiol, 4-tert-butylcyclohexane-1,1-dithiol, 1,2-benzenedithiol,
1,3-benzenedithiol, 1,4-benzenedithiol, 1,3,5-benzenetrithiol.

(3) Esterified product of a polyol and a thiol compound having a carboxyl group: Examples of the thiol having a carboxyl group include mercaptoacetic acid, thioglycolic acid, α-mercaptopropionic acid, β-mercaptopropionic acid, 4-mercaptobutyric acid, Mercaptoundecylic acid, o-mercaptobenzoic acid, p-mercaptobenzoic acid.

The polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, Dipropylene glycol, neopentyl glycol, triethylene glycol, p-xylylene glycol, hydrogenated bisphenol A, bisphenol dihydroxypropyl ether, glycerin, trimethylolethane, trimethylolpropane, trishydroxymethylaminomethane, pentaerythritol, dipenta Erythrit, sorbitol and the like can be mentioned.

Further, polypropylene glycol, polyethylene glycol, polytetramethylene glycol,
Ethylene oxide-propylene oxide copolymer,
Tetrahydrofuran-ethylene oxide copolymer, tetrahydrofuran-propylene oxide copolymer, etc., and polyester diols such as polyethylene adipate, polypropylene adipate, polyhexamethylene adipate, polyneopentyl adipate, polyhexamethylene neopentyl adipate, polyethylene hexamethylene Adipate and the like can also be mentioned, such as poly-ε-caprolactone diol, polyhexamethylene carbonate diol, polytetramethylene adipate, sorbitol, methyl glucozite, and shucrose. Further, various phosphorus-containing polyols, halogen-containing polyols and the like can be used as the polyol.

These polyols and thiol compounds having a carboxyl group can be used in all combinations, and the desired compounds can be obtained by an esterification reaction according to a known method.

Among the above compounds having two or more thiol groups in one molecule, aliphatic hydrocarbons for the purpose of imparting flexibility to the heat-sensitive layer of the present invention and improving the printing durability of the printing plate are also used. The esterified product of a dithiol and a polyol having a main chain and a thiol compound having a carboxyl group is preferable, and more preferably trimethylolpropane or pentaerythritol and thioglycolic acid or β
-Esterified products by a combination of mercaptopropionic acid or a mixture thereof are preferred.

The proportion of the compound having a thiol group (c) of the present invention in the heat-sensitive layer is preferably from 5 to 80% by weight, more preferably from 10 to 80% by weight on a solids basis. If it exceeds 80% by weight, the original function of each layer is significantly reduced, and if it is less than 5% by weight, the laser sensitivity is insufficient.

Next, (d) a substance which generates a radical by heating, which is used in the present invention, will be described.

As the substance which generates a radical by heating, all known compounds can be used. Specific examples include organic peroxides, azo compounds and sulfides.

As the organic peroxide, those having a decomposition temperature of 120 ° C. or higher for a half-life of 1 minute are preferable from the viewpoint of the storage stability of the unexposed printing plate precursor. Specific examples of such an organically modified oxide include 2,4-dichlorobenzoyl peroxide, cumyl peroxy octoate, acetyl peroxide, succinic peroxide, t
-Butylperoxy (2-ethylhexanoate), m
-Toluolyl peroxide, benzoyl peroxide, t-butylperoxysobutyrate, 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxide) Oxy) cyclohexane, t-butylperoxymaleic acid, t-
Butylperoxylaurate, t-butylperoxy 3,5,5-trimethylhexanoate, cyclohexanone peroxide, t-butylperoxyallyl carbonate, t-butylperoxyisopropyl carbonate, 2,5-dimethyl-2, 5-di (benzoylperoxy) hexane, 2,2-bis (t-butylperoxy) octane, t-butylperoxyacetate,
2-bis (t-butylperoxy) butane, t-butylperoxybenzoate, n-butyl-4,4-bis (t-butylperoxy) valerate, di-t-butylperoxyisophthalate, methyl ethyl ketone peroxide, Dicumyl peroxide, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane, α,
α'-bis (t-butylperoxy-m-isopropyl) benzene, t-butylcumyl peroxide, diisopropylbenzene hydroperoxide, di-t-butyl peroxide, p-menthanehydroperoxide, 2,5-dimethyl- 2,5-di (t-butylperoxy) hexyne, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethylhexane-
Examples thereof include 2,5-dihydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide and the like.

Specific examples of the azo compound include azobisisobutylnitrile, 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2-cyano-2-propylazoformamide, 1,1-azobiscyclohexane- Examples thereof include 1-carbonitrile, 1,1′-azobis (1-acetoxy-1-phenylene), and 2,2′-azobis (2-amidobutane) dihydrochloride.

Specific examples of the sulfides include known monosulfides, disulfides, tetramethylthiuram disulfide and the like.

Among these substances which generate radicals by heating, organic peroxides are preferred.

The proportion of the substance (d) of the present invention which generates radicals by heating in the heat-sensitive layer is preferably 0.1 to 10% by weight, more preferably 0.1 to 7% by weight, based on the solid content. is there. If it exceeds 10% by weight, the original function of each layer is reduced, and if it is less than 0.1% by weight, the laser sensitivity is insufficient.

Further, the heat-sensitive layer of the present invention preferably contains (e) a substance which generates an acid upon heating. The acid generated by heating accelerates the thermosetting reaction of the thermosensitive layer,
As a result, the sensitivity of the printing plate precursor can be improved. Specific examples of the substance that generates an acid by heating include the following, but the present invention is not limited thereto.

(1) Onium salt: Examples include an iodinium salt, a sulfonium salt, a phosphonium salt, a pyridium salt, and a diazonium salt. Preferably, diphenyliodonium triflate, diphenyliodonium pyrene sulfonate, diphenyliodonium dodecylbenzenesulfonate, triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium naphthalenesulfonate, (hydroxyphenyl) benzylmethylsulfonium toluenesulfonate and the like is there.

(2) Halogen-containing compounds: Examples include haloalkyl group-containing heterocyclic compounds, haloalkyl group-containing hydrocarbon compounds, and the like. Specific examples include an acetophenone compound containing a halogen, a pyrone compound, a triazine compound, and an oxazole compound. Preferably, phenyl-bis (trichloromethyl) -s-triazine, methoxyphenyl-bis (trichloromethyl) -s-triazine, naphthyl-bis (trichloromethyl) -s-triazine, 1,1-bis (4
-Chlorophenyl) -2,2,2-trichloroethane,
Trichloroacetophenone, decyl chloride (2-chloro-2-phenylacetophenone) and the like.

(3) Sulfone compound: β-ketosulfone, β-sulfonylsulfone and their α-diazo compounds can be mentioned. Preferred are phenacylphenylsulfone, mesitylphenacylsulfone, triboromomethylphenylsulfone, bis (phenylsulfonyl) methane, bis (phenylsulfonyl) diazomethane and the like.

(4) Sulfonate compounds: Examples thereof include alkylsulfonic acid esters, haloalkylsulfonic acid esters, arylsulfonic acid esters, and iminosulfonate. Preferred are benzoin tosylate, pyrogallol tris triflate, nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate, 2,6-dinitrobenzylsulfonate ester, o-nitrobenzylsulfonate ester and the like. Other examples include N-imidoyl ester, pyrogallol ester, nitrobenzyl ester, α-sulfonyloxyketone, and tris (trichloromethyl) triazine.

Among these substances that generate an acid by heating, there are substances that decompose even by visible light or ultraviolet light to generate an acid. In the case of such a compound that decomposes by light, it is possible to impart resistance to light exposure in a bright room by adding a dye that absorbs a wavelength range felt by the compound to the heat-sensitive layer. In addition, when the above-mentioned black dye is used, the black dye generally has an absorption range up to the visible light region and the ultraviolet region, so that exposure resistance can be imparted without using other dyes.

The proportion of the substance (e) of the present invention which generates an acid by heating in the heat-sensitive layer is preferably 0.1 to 10% by weight, more preferably 0.1 to 7% by weight, based on the solid content. is there. If it exceeds 10% by weight, the original function of each layer is significantly reduced, and if it is less than 0.1% by weight, the laser sensitivity becomes low.

The heat-sensitive layer of the present invention comprises, in addition to the compounds described above,
It preferably contains a binder polymer. The binder polymer is not particularly limited as long as it is soluble in an organic solvent and has a film forming ability. However, from the viewpoint of the printing durability of the printing plate, the glass transition temperature (Tg) of the polymer is 0 ° C. or lower. It is preferable to use a polymer or copolymer of
Further, it is preferable to use a polymer having a Tg of −30 ° C. or less.

The glass transition temperature Tg (glass transition temperature)
The term “temperature” refers to a transition point (temperature) at which the physical properties of the amorphous polymer material change from a glassy state to a rubbery state (or vice versa). In a relatively narrow temperature region around the transition point, not only the elastic modulus, but also the expansion rate,
Various physical properties such as heat content, refractive index, diffusion coefficient, and dielectric constant also change greatly. Therefore, the measurement of the glass transition temperature includes a volume (specific volume) -temperature curve, a measurement of heat content by thermal analysis (DSC, DTA, etc.), a measurement of properties of the whole substance such as a refractive index and stiffness, and a measurement of mechanical properties. Some measure quantities that reflect molecular motion (such as dynamic viscoelasticity), dielectric loss tangent, and NMR spectra. It is customary to use a dilatometer to measure the volume of the sample while increasing the temperature and determine it as the point where the slope of the volume (specific volume) -temperature curve changes rapidly. In the present invention, any binder polymer which can be diluted with an organic solvent and has a film-forming ability can be used as the binder polymer which has the function of retaining the form. Specific examples of the binder polymer include the following,
The present invention is not limited to these examples.

(1) Vinyl polymers: polymers and copolymers obtained from the following monomers and their derivatives. For example, ethylene, propylene, 1-butene, styrene, butadiene, isoprene, vinyl chloride,
Vinyl acetate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, N-hexyl methacrylate, lauryl methacrylate, acrylic acid, methacrylic acid, maleic acid, itaconic acid, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate,
2-hydroxypropyl acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) acrylate, 2- (meth) acryloxyethyl hydrogen naphthalate, 2- (meth) acryloxyethyl Hydrogen succinate, acrylamide, N-methylol acrylamide, diacetone acrylamide, glycidyl methacrylate, acrylonitrile, styrene, vinyl toluene, isobutene, 3-methyl-1-butene, butyl vinyl ether, N-vinyl carbazole, methyl vinyl ketone, nitroethylene, α-Methyl cyaniacrylate, vinylidene cyanide, polyethylene glycol di (meth) acrylate, trimethylolethanetri (meth) acrylate Neopentyl glycol di (meth)
Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, glycerin and trimethylol Polymers and copolymers obtained by polymerizing and copolymerizing (meth) acrylates after adding ethylene oxide or propylene oxide to polyfunctional alcohols such as ethane and trimethylolpropane as binder polymers Can be used.

Specific examples of the vinyl polymer having a glass transition temperature of 0 ° C. or lower include, for example, the following polymers, but the present invention is not limited thereto.

(A) Polyolefins: Specific examples include poly (1-butene) and poly (5-cyclohexyl-1-)
Pentene), poly (1-decene), poly (1,1-dichloroethylene), poly (1,1-dimethylbutane), poly (1,1-dimethylpropane), poly (1-dodecene), polyethylene, poly ( 1-heptene), poly (1
-Hexene), polymethylene, poly (6-methyl-1-)
Heptene), poly (5-methyl-1-hexene), poly (2-methylpropane), poly (1-nomene), poly (1-octene), poly (1-pentene), poly (5-pentene)
Phenyl-1-pentene), polypropylene, polyisobutylene, poly (1-butene), poly (vinyl butyl ether), poly (vinyl ethyl ether), poly (vinyl isobutyl ether), poly (vinyl methyl ether) and the like.

(B) Polystyrenes: Specific examples are poly (4-[(2-butoxyethoxy) methyl] styrene), poly (4-decylstyrene), poly (4-dodecylstyrene), and poly [4- ( 2-ethoxyethoxymethyl) styrene], poly [4- (hexoxymethyl) styrene], poly (4-hexylstyrene), poly (4-nonylstyrene), poly [4- (octoxymethyl) styrene], poly (4 -Octylstyrene), poly (4-tetradecylstyrene) and the like.

(C) Acrylic acid ester polymer and methacrylic acid ester polymer: specific examples are poly (butyl acrylate), poly (sec-butyl acrylate), poly (tert-butyl acrylate), poly [2- (2-cyanoethyl) Thio) ethyl acrylate], poly [3- (2-cyanoethylthio) propyl acrylate], poly [2- (cyanomethylthio) ethyl acrylate], poly [6- (cyanomethylthio) hexyl acrylate], poly [2- (3 -Cyanopropylthio) ethyl acrylate], poly (2-ethoxyethyl acrylate), poly (3-ethoxypropyl acrylate), poly (ethyl acrylate), poly (2-ethylbutyl acrylate), poly (2-ethylhexyl acrylate), Poly (5 Ethyl-2-nonyl acrylate), poly (2-ethyl-thioethyl acrylate), poly (3-ethyl thio propyl acrylate),
Poly (heptyl acrylate), poly (2-heptyl acrylate), poly (hexyl acrylate), poly (isobutyl acrylate), poly (isopropyl acrylate), poly (2-methoxyethyl acrylate), poly (3-methoxypropyl acrylate), Poly (2-methylbutyl acrylate), poly (3-methylbutyl acrylate), poly (2-methyl-7-ethyl-4-undecyl acrylate), poly (2-methylpentyl acrylate), poly (4-methylbutyl acrylate) Methyl-2-pentyl acrylate), poly (4-methylthiobutyl acrylate), poly (2-methylthioethyl acrylate), poly (3-methylthiopropyl acrylate),
Poly (nonyl acrylate), poly (octyl acrylate), poly (2-octyl acrylate) poly (3-
Pentyl acrylate), poly (propyl acrylate), poly (hydroxyethyl acrylate), poly (hydroxypropyl acrylate) and the like.

Examples of polymethacrylates having a glass transition temperature of 0 ° C. or lower include poly (ethyl acrylate), poly (butyl acrylate), poly (decyl methacrylate), poly (dodecyl methacrylate), poly (2-ethylhexyl methacrylate), and poly (2-ethylhexyl methacrylate). Octadecyl methacrylate), poly (octyl methacrylate), poly (tetradecyl methacrylate), poly (n-hexyl methacrylate), poly (lauryl methacrylate), and copolymers of these polymers with other acrylic polymers.

(2) Unvulcanized rubber: natural rubber, (NR)
Or a homopolymer or a copolymer selected from butadiene, isoprene, styrene, acrylonitrile, acrylates and methacrylates, such as polybutadiene (BR) and styrene-butadiene copolymer (S
BR), carboxy-modified styrene-butadiene copolymer, polyisoprene (NR), polyisobutylene, polychloroprene (CR), polyneoprene, acrylate-butadiene copolymer, methacrylate-
Butadiene copolymer, acrylate-acrylonitrile copolymer (ANM), isobutylene-isoprene copolymer (IIR), acrylonitrile-butadiene copolymer (NBR), carboxy-modified acrylonitrile
Butadiene copolymer, acrylonitrile-chloroprene copolymer, acrylonitrile-isoprene copolymer, ethylene-propylene copolymer (EPM, EPDM), vinylpyridine-styrene-butadiene copolymer, styrene-isoprene copolymer, etc. Vulcanized rubber.

Further, poly (1,3-butadiene), poly (2-chloro-1,3-butadiene), poly (2-decyl-1,3-butadiene), poly (2,3-dimethyl-
1,3-butadiene), poly (2-ethyl-1,3-butadiene), poly (2-heptyl-1,3-butadiene), poly (2-isopropyl-1,3-butadiene), poly (2- Methyl-1,3-butadiene), chlorosulfonated polyethylene, and cyclized rubber.

Further, modified products of these rubbers, for example, rubbers which have been subjected to ordinary modification such as epoxidation, chlorination, carboxylation, etc., and blends with other polymers can also be used as the binder polymer.

(3) Polyoxides (polyethers): trioxane, ethylene oxide, propylene oxide, 2,3-epoxybutane, 3,4-epoxybutene, 2,3-epoxypentane, 1,2-epoxyhexane, epoxy Cyclohexane, epoxycycloheptane, epoxycyclooctane, styrene oxide,
-Phenyl-1,2-epoxypropane, tetramethylethylene oxide, epichlorohydrin, epibromohydrin, allyl glycidyl ether, phenyl glycidyl ether, n-butyl glycidyl ether, 1,4-
Polymers by ring-opening polymerization such as dichloro-2,3-epoxybutane, 2,3-epoxypropionaldehyde, 2,3-epoxy-2-methylpropionaldehyde, and 2,3-epoxydiethyl acetal, copolymers, and the like.

Specific examples of polyoxides having a glass transition temperature of 0 ° C. or lower include, for example, polyacetaldehyde, poly (butadiene oxide), poly (1-butene oxide), poly (dodecene oxide), poly (ethylene oxide) and poly (ethylene oxide). Isobutene oxide), polyformaldehyde, poly (propylene oxide), poly (tetramethylene oxide), poly (trimethylene oxide) and the like.

(4) Polyesters: Polyesters obtained by polycondensation of polyhydric alcohols and polycarboxylic acids, polyesters obtained by polymerization of polyhydric alcohols and polycarboxylic anhydrides, and lactones shown below. Examples include polyester obtained by ring polymerization and the like, and polyester obtained from a mixture of these polyhydric alcohols, polycarboxylic acids, polycarboxylic anhydrides, and lactones.

Specific examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butylene glycol, 1,5-pentanediol, 1,6- Hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, triethylene glycol, p-xylene glycol, hydrogenated bisphenol A, bisphenol hydroxypropyl ether,
Glycerin, trimethylolethane, trimethylolpropane, trishydroxymethylaminomethane, pentaerythritol, dipentaerythritol, sorbitol and the like can be mentioned.

Specific examples of polycarboxylic acids and polycarboxylic anhydrides include phthalic anhydride, isophthalic acid, terephthalic acid, succinic anhydride, adipic acid, azelaic acid, and the like.
Sebacic acid, Tetrahydrophthalic anhydride, Hexahydrophthalic anhydride, Tetrabromophthalic anhydride, Tetrachlorophthalic anhydride, Hetic anhydride, Hymic anhydride, Maleic anhydride, Fumaric acid, Itaconic acid, Trimellitic anhydride, Methylcyclohexentricarboxylic acid Anhydride, pyromellitic anhydride and the like can be mentioned.

Examples of the lactone include β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone and the like.

Specific examples of the polyester having a glass transition temperature of 0 ° C. or lower include, for example, poly [1,4- (2-butene)
Sebacate], [1,4- (2-butyne) sebacate], poly (decamethylenadipate), poly (ethylene adipate), poly (oxydiethylene adipate),
Poly (oxydiethylene azelate), poly (oxydiethylene dodecanediate), poly (oxydiethylene glutarate), poly (oxydiethylene heptyl malonate), poly (oxydiethylene nonyl malonate), poly (oxydiethylene octadecandiate) Eight), poly (oxydietin oxalate), poly (oxydiethylene pentyl malonate), poly (oxydiethylene pimerate), poly (oxydiethylene propyl malonate), poly (oxydiethylene sebacate), poly (oxydiethylene sebacate) Oxydiethylene superate), poly (oxyethylene succinate), poly (pentamethylene adipate), poly (tetramethylene adipate), poly (tetramethylene sebacate), poly (trimethylene adipate) and the like. .

(5) Polyurethanes: Polyurethanes obtained from the following polyisocyanates and polyhydric alcohols can also be used as the binder polymer. As the polyhydric alcohol, the polyhydric alcohols described in the section of the polyester and the following polyhydric alcohols,
Polyester polyols having both hydroxyl groups at both ends obtained by polycondensation of the polyhydric carboxylic acids described in the section of the polyesters and the polyhydric alcohols, polymerized polyester polyols obtained from the above lactones, polycarbonate diols, propylene oxide and tetrahydrofuran. Examples thereof include polyether polyols obtained by ring-opening polymerization or modification of an epoxy resin, acrylic polyols which are a copolymer of a (meth) acrylic monomer having a hydroxyl group and a (meth) acrylic acid ester, and polybutadiene polyols.

As the isocyanates, paraphenylene diisocyanate, 2,4- or 2,6-toluylene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (MDI), tolidine diisocyanate (TODI), xylylene diisocyanate (XD
I), hydrogenated xylylene diisocyanate, cyclohexane diisocyanate, meta-xylylene diisocyanate (MXDI), hexamethylene diisocyanate (H
DI or HMDI), lysine diisocyanate (L
DI) (alias 4,4′-methylenebis (cyclohexyl isocyanate)), hydrogenated TDI (HTDI) (alias methylcyclohexane 2,4 (2,6) diisocyanate), hydrogenated XDI (H6XDI) (alias 1,3- ( Isocyanatomethyl) cyclohexane), isophorone diisocyanate (IPDI), diphenyl ether isocyanate, trimethylhexamethylene diisocyanate (TMDI), tetramethyl xylylene diisocyanate, polymethylene polyphenyl isocyanate, dimer acid diisocyanate (DDI), triphenylmethane triisocyanate, tris (Isocyanate phenyl) thiophosphate, tetramethyl xylylene diisocyanate, lysine ester triisocyanate,
1,6,11-undecane triisocyanate, 1,8
-Diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene triisocyanate,
Examples include bicycloheptane triisocyanate and the like, polyhydric alcohol adducts of polyisocyanates, and polymers of polyisocyanates.

Representative polyhydric alcohols other than those described in the section of polyester include polypropylene glycol, polyethylene glycol, polytetramethylene glycol, ethylene oxide-propylene oxide copolymer, and tetrahydrofuran-propylene oxide copolymer. , And as the polyester diol, polyethylene adipate, polypropylene adipate,
Polyhexamethylene neopentyl adipate, polyneopentyl adipate, polyhexamethylene neopentyl adipate,
Examples thereof include polyethylene hexamethylene adipate and the like, and poly-ε-caprolactone diol, polyhexamethylene carbonate diol, polytetramethylene adipate, sorbitol, methyl glucosit, sucrose and the like.

In addition, various phosphorus-containing polyols and halogen-containing polyols can be used as the polyol.

The above-mentioned isocyanates and polyols can be reacted by a known method to obtain a desired polyurethane. These polyurethanes generally have a glass transition temperature of 0 ° C. or lower and can be used in the present invention. .

(6) Polyamides: Copolymers of the following monomers may be mentioned. As monomers, ε
-Caprolactam, ω-laurolactam, ω-aminoundecanoic acid, hexamethylenediamine, 4,4-bis-
Examples include aminocyclohexylmethane, 2,4,4-trimethylhexamethylenediamine, isophoronediamine, glycols, isophthalic acid, adipic acid, sebacic acid, dodecanoic acid and the like.

More specifically, polyamides are generally classified into water-soluble polyamides and alcohol-soluble polyamides. Examples of the water-soluble polyamide include polyamides containing a sulfonic acid group or a sulfonate group obtained by copolymerizing sodium 3,5-dicarboxybenzenesulfonate as disclosed in JP-A-48-72250. JP-A-49-43465
Japanese Patent Application Laid-Open No. Sho 50-7605 discloses a polyamide having an ether bond obtained by copolymerizing any one of dicarboxylic acids, diamines and cyclic amides having an ether bond in a molecule as disclosed in JP-A-50-7605. Polyamide containing basic nitrogen obtained by copolymerizing N, N'-di (γ-aminopropyl) piperazine and the like as disclosed in the official gazette and polyamide obtained by quaternizing these polyamides with acrylic acid or the like A copolymer polyamide containing a polyether segment having a molecular weight of 150 to 1500 proposed in JP-A-55-74537;
Ring-opening polymerization of (N, N′-dialkylamino) -ε-caprolactam or α- (N, N′-dialkylamino)
And polyamide obtained by ring-opening copolymerization of -ε-caprolactam and ε-caprolactam.

Examples of the alcohol-soluble polyamide include linear polyamides synthesized from dibasic acid fatty acids and diamines, ω-amino acids, lactams or derivatives thereof by a known method. Polymers and the like can also be used. Typical examples include nylon 3, 4, 5, 6, 8, 1
1, 12, 13, 66, 610, 6/10, 13/1
3, polyamide from meta-xylylenediamine and adipic acid, polyamide from trimethylhexamethylenediamine or isophoronediamine and adipic acid, ε-caprolactam / adipic acid / hexamethylenediamine /
4,4′-diaminodicyclohexylmethane copolymerized polyamide, ε-caprolactam / adipic acid / hexamethylenediamine / 2,4,4′-trimethylhexamethylenediamine copolymerized polyamide, ε-caprolactam / adipic acid / hexamethylenediamine / isophorone Diamine copolymerized polyamides, polyamides containing these components, N-methylol and N-alkoxymethyl derivatives thereof can also be used.

The above polyamides can be used alone or in combination for the primer layer of the present invention.

As the polyamide having a glass transition temperature of 0 ° C. or less, a copolymerized polyamide containing a polyether segment having a molecular weight of 150 to 1500, more specifically, a polyether segment having an amino group at a terminal and having a molecular weight of 150 to 1500 is preferred. A structural unit composed of polyoxyethylene of 1500 and an aliphatic dicarboxylic acid or diamine of 30 to
Copolymer polyamides containing 70% by weight may be mentioned, but the present invention is not limited to these.

These polymers that can be used as the binder polymer may be used alone, or a mixture of several kinds of polymers may be used.

Among the above-mentioned polymers, polyurethane, polyester, vinyl-based polymer and unvulcanized rubber are preferable as the polymer which can be preferably used in the heat-sensitive layer of the present invention.

When the substrate is made of a material having a relatively high thermal conductivity such as a metal and the like, and the substrate is made of a material having a relatively high thermal conductivity, a heat insulating layer is provided between the substrate and the heat sensitive layer for the purpose of a heat insulating effect. It is preferred to provide a layer.

The heat insulating layer used in the present invention must satisfy the following conditions. That is, the substrate and the heat-sensitive layer are well adhered to each other and stable over time, and have good solvent resistance to a developing solution and a solvent used for printing. Further, the heat insulating layer also has a role as a thermal insulating layer for preventing the heat when the heat-sensitive layer causes a thermal reaction from diffusing to the substrate. Those satisfying such conditions include those containing an epoxy resin as disclosed in JP-B-61-54219, as well as polyurethane resins, phenol resins, acrylic resins, alkyd resins, polyester resins, polyamide resins, melamine resins. , Urea resin, benzoguanamine resin, vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, polyvinyl butyral resin, ethylene
Vinyl acetate copolymer, polycarbonate resin, polyacrylonitrile-butadiene copolymer, polyether resin, polyethersulfone resin, milk casein, gelatin and the like can be used. These resins can be used alone or in combination of two or more. Further, a composition obtained by photocuring a composition similar to that of the heat-sensitive layer may be used.

Among these, it is preferable to use a polyurethane resin, a polyester resin, an acrylic resin, an epoxy resin, a urea resin, or the like alone or as a mixture of two or more.

As the anchoring agent constituting the heat insulating layer, a known adhesive such as a silane coupling agent can be used, and a phosphorus-containing compound, an organic titanate or the like is also effective.

For the purpose of further improving the coatability, it is optional to add a surfactant.

It is preferable that the heat insulating layer contains an additive such as a white pigment to improve plate inspection.

The composition for forming the above-mentioned heat insulating layer is as follows:
It is prepared as a composition solution by dissolving in a suitable organic solvent such as DMF, methyl ethyl ketone, methyl isobutyl ketone, dioxane and the like. Such a composition solution is uniformly applied on a substrate and heated at a required temperature for a required time to form a heat insulating layer.

[0130] The thickness of the heat insulating layer is 0.5 to 50
g / m ² , more preferably 1 to 10 g / m ²
It is. When the thickness is less than 0.5 g / m ² , the effect of blocking morphological defects and chemical adverse effects on the substrate surface is inferior, and 50 g / m ²
If the thickness is greater than / m ^2, it is disadvantageous from an economic viewpoint, so the above range is preferable.

The heat-sensitive layer of the present invention may further contain a dye having absorption in a region other than the wavelength of the laser beam, a known polymerization inhibitor, an acid, a leveling agent, a surfactant, a plasticizer, and the like.
It can be arbitrarily added as needed.

Further, the heat-sensitive layer of the present invention may optionally contain a dye having absorption in a region other than the wavelength of the laser beam, a known polymerization inhibitor, an acid, a leveling agent, a surfactant, a plasticizer, and the like, if necessary. Can be added.

The heat-sensitive cured layer of the present invention preferably contains (f) an epoxy compound. The epoxy compound used for the thermosetting layer of the present invention is not particularly limited, but a polyfunctional epoxy compound is particularly preferably used.

The proportion of the epoxy compound (f) in the photosensitive layer of the present invention is preferably 30% by weight or less based on the solid content. If it exceeds 30% by weight, the laser sensitivity tends to decrease.

These compositions are preferably diluted in a known organic solvent and prepared as a heat-sensitive layer solution before use.

The composition for forming the heat-sensitive layer is as follows:
The composition solution is prepared by dissolving in a suitable organic solvent such as DMF, methyl ethyl ketone, methyl isobutyl ketone, dioxane, and ethyl cellosolve. Such a composition solution is uniformly applied on a substrate by a known method, and heated at a required temperature for a required time to form a heat-sensitive cured layer.

The thickness of the heat-sensitive layer is 0.1 to 1 as a coating layer.
0 g / m ² is preferable, and more preferably 1 to 7 g / m ²
It is. The thickness tends to decrease printing durability of thin, the printing plate than 0.1 g / m ² is not preferable, 10 g / m ²
When the thickness is larger than the above range, it takes time to volatilize the diluting solvent, which is disadvantageous in terms of productivity.

Next, the hydrophilic swelling layer of the present invention will be described.

The hydrophilic swelling layer used in the present invention contains a hydrophilic polymer as a component. The hydrophilicity in the present invention means a property of being substantially insoluble in water and exhibiting water swelling property, and a known hydrophilic polymer is laminated on a substrate by coating or transfer, and a known method is used. A water-swellable hydrophilic swelling layer which is cross-linked or pseudo-cross-linked and made insoluble in water is used.

As the hydrophilic polymer here, known water-soluble polymers (meaning those completely soluble in water),
Pseudo water-soluble polymer (meaning amphipathic, macro means soluble in water but micro means insoluble), water swelling polymer (meaning that swells in water but does not dissolve) ). That is, it refers to a polymer that adsorbs or absorbs water under normal use conditions, and a polymer that dissolves in or swells in water.

In the present invention, as the hydrophilic polymer, known hydrophilic polymers can be used, including animal-based polymers, plant-based polymers, and synthetic polymers. For example, "Functional Monomers"
(Y. Nyquist, Dekker), "Water-soluble polymer" (Nakamura, Chemical Industry Co., Ltd.), "Latest processing / modification technology of water-soluble polymer water-dispersible resin and application development Comprehensive technical materials" (Management Development Center Publishing Department), and “Applications and Markets of New Water-Soluble Polymers” (CMC). Specific examples are shown below.

(A) Natural polymers: starch-acrylonitrile-based graft polymer hydrolyzate, starch-acrylic acid-based graft polymer, starch-styrene sulfonic acid-based graft polymer, starch-vinyl sulfonic acid-based graft polymer , Starch-acrylamide-based graft polymer, carboxylated methylcellulose, methylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, xanthate cellulose,
Cellulose-acrylonitrile-based graft polymer, cellulose-styrenesulfonic acid-based graft polymer, carboxymethylcellulose-based cross-linked product, hyaluronic acid, agarose, collagen, milk casein, acid casein, rennet casein, ammonia casein, calicase casein, borax Casein, glue, gelatin, gluten, soy protein, alginate, ammonium alginate, potassium alginate, sodium alginate gum arabic,
Tragacanth gum, karaya gum, guar gum, locust bean gum, Irish moss, soy lecithin, pectic acid, starch, carboxylated starch, agar, dextrin, mannan, etc.

(B) Synthetic polymers: polyvinyl alcohol, polyethylene oxide, poly (ethylene oxide-CO-propylene oxide), aqueous urethane resin, water-soluble polyester, hydroxyethyl (meth)
Acrylate-based polymer ((meth) □□□□
The abbreviations for □□□□ or meta □□□□ are abbreviated. ), Poly (vinyl methyl ether-CO-maleic anhydride), maleic anhydride copolymer, vinylpyrrolidone copolymer, polyethylene glycol di (meth)
Acrylate-based crosslinked polymer, polypropylene glycol di (meth) acrylate-based crosslinked polymer, poly (N-vinylcarboxylic amide), N-vinylcarboxylic amide copolymer, and the like.

The above-mentioned hydrophilic polymer may contain one or more monomers or copolymer components having different substituents for the purpose of imparting flexibility or controlling hydrophilicity, as long as the effects of the present invention are not impaired. It is possible to mix and use more than one kind as appropriate.

Specific examples of the hydrophilic polymer preferably used in the present invention are shown below, but the present invention is not limited to these examples.

(1) maleic acid or maleic anhydride,
Maleic acid derivatives such as maleic amide or maleic imide and ethylene, propylene, butylene, isobutylene or diisobutylene having 2 to 12 carbon atoms;
Preferably, a crosslinked product of a reaction product of a copolymer with a linear or branched α-olefin having 2 to 8 carbon atoms and an alkali metal compound, an alkaline earth metal compound, ammonia, or an amine.

(2) A copolymer of maleic acid or a derivative thereof with a vinyl or vinylidene compound such as styrene, vinyl acetate, methyl vinyl ether, acrylate, methacrylate or acrylonitrile, and an alkali metal compound or an alkaline earth metal Crosslinked product of reaction product with compound, ammonia and amine.

(3) A crosslinked product of a reaction product of a copolymer of acrylic acid or methacrylic acid with the vinyl or vinylidene compound of the above (2), and an alkali metal compound, an alkaline earth metal compound, ammonia and an amine.

A polyoxyalkylene hydrophilic polymer disclosed in JP-B-58-37027 and the like, polyvinylpyrrolidone disclosed in JP-A-60-104106 and the like, and a sulfonic acid group as a hydrophilic group Crosslinked products such as polystyrenesulfonic acid and acrylamidomethylpropanesulfonic acid copolymer
Polyurethane resins obtained by crosslinking a hydrophilic polymer having a hydroxyl group or an amino group with a polyisocyanate, which are disclosed in Japanese Patent No. 42416, and the like.

Next, a method for crosslinking a hydrophilic polymer will be described.

The hydrophilic swelling layer is formed by cross-linking or pseudo-cross-linking at least one of the above-mentioned hydrophilic polymers as necessary, and is formed on a substrate. Crosslinking is performed by performing a crosslinking reaction using a reactive functional group of the hydrophilic polymer. The cross-linking reaction may be covalent cross-linking or ionic cross-linking.

Examples of the compound used for the crosslinking reaction include known polyfunctional compounds having a crosslinking property, such as polyepoxy compounds, polyisocyanate compounds, poly (meth) acrylic compounds, polymercapto compounds, polyalkoxysilyl compounds, Polyvalent metal salt compounds, polyamine compounds, aldehyde compounds, polyvinyl compounds, hydrazine and the like, and the crosslinking reaction is performed by adding a known catalyst,
The reaction is promoted.

Specific examples of known cross-linkable polyfunctional compounds include the following compounds.

(1) Sublimation sulfur, by-product sulfur produced by oxidizing hydrogen sulfide, colloidal sulfur produced by oxidizing hydrogen sulfide in a wet manner, and the like: dithiomorpholine which is decomposed by heating to generate sulfur, Thioplast tetramethylthiuram disulfide, tetramethylthiuram monosulfide, thiuram-based compounds such as dipentamethylenethiuram tetrasulfide, piperidine pentamethylenethiocarbamate, pipecoline pipecolyl dithiocarbamate, dithiocarbamate compounds such as sodium dimethyldithiocarbamate, Xanthate compounds such as sodium isopropylxanthate and zinc butylxanthate; thiourea compounds such as thiourea and thiocarbanilide; zinc salts of thiazoles such as diphenylguanidine; mercap Sodium salt of benzothiazole, dibenzothiazyl disulfide, etc. thiazole compounds such as cyclohexylamine salt of mercaptobenzothiazole.

(2) Aldehydeamine compounds such as butyraldehyde-monobutylamine condensate, butyraldehyde-aniline condensate, heptaldehyde-aniline reactant, ethyl salt-formaldehyde-ammonia reactant, zinc oxide, tellurium, selenium, Ammonia zirconium carbonate, organic peroxides such as benzoyl peroxide, dicumyl peroxide, etc .: Further, as a crosslinking accelerator, zinc carbonate, stearic acid, oleic acid, lauric acid, zinc stearate, dibutylammonium oleate, diethanolamine , Triethanolamine, diethylene glycol and the like.

(3) Polyepoxy compounds, phenolic resins (polycondensates of phenols containing hydrocarbon-substituted phenols and formaldehyde), glycidyl etherified phenolic resins, urea resins, polyamines, melamine resins, benzoguanamine resins, acid anhydrides Etc. Specific examples of polyepoxy compounds include glycerin polyglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether,
Examples include trimethylolpropane polyglycidyl ether, trimethylolpropane polyglycidyl ether, sorbitol polyglycidyl ether, bisphenols, and polycondensates of hydrogenated products thereof and epihalohydrin. Specific examples of polyamines include:
Examples include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenediamine, propylenediamine, polyethyleneimine, and polyamideamine.

(4) Polyisocyanate compound: Examples of the polyisocyanate compound include tolylene diisocyanate, diphenylmethane isocyanate, liquid diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, xylylene diisocyanate, and the like.
Aromatic isocyanates such as naphthalene-1,5-diisocyanate, cyclohexanephenylene diisocyanate, isopropylbenzene-2,4-diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate and decamethylene diisocyanate; alicyclics such as cyclohexyl diisocyanate and isophorone diisocyanate Examples include diisocyanates and addition products of polypropylene glycol / tolylene diisocyanate.

(5) Silane compounds: methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane, vinyltriethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -Γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,
β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, 3-chloropropylmethyldimethoxysilane, vinyltris (methylethylketoxime) silane, methyltris (methylethylketoxime) silane , Vinyltriacetoxysilane, etc.

(6) Titanate compounds: tetraethyl orthosilicate, bis (dioctyl pyrophosphate) ethylene titanate, isopropyl triactanoyl titanate, isopropyl dimethacryl isostearyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl (dioctyl phosphate) titanate), Isopropyl tricumyl phenyl titanate, isopropyl tri (N-aminoethylaminoethyl) titanate, dicumyl phenyloxy acetate titanate, diisostearoyl ethylene titanate, isopropyl triin stearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl phosphate) Titanate, tetraisop Pyrbis (dioctyl phosphite) titanate, tetraoctyl bis (ditridisyl phosphite) titanate, tetra (2,2 diallyloxymethyl-1-butyl) bis (ditridecyl phosphite titanate, bis (dioctyl pyrophosphate) oxyacetate Titanates, bis (dioctyl pyrophosphate) oxyacetate titanates, and the like.

(7) Aldehyde compounds: formaldehyde, acetaldehyde, propylaldehyde, butyraldehyde, glyoxal, glutaraldehyde, terephthalaldehyde, etc.

These crosslinking agents can be used alone or in combination of two or more. Water is mainly used as the dispersion medium, but a known organic solvent can be added as necessary.

As a method for forming the hydrophilic swelling layer of the present invention, a method in which a crosslinking agent is added as necessary in an aqueous solution system is preferable since a uniform crosslinked structure is formed and ink repellency is improved. preferable.

Accordingly, it is particularly preferable to use a water-soluble polyfunctional compound as the crosslinking agent used in the present invention. That is, it is preferable to use a water-soluble polyepoxy compound, polyamine compound, melamine compound, aldehyde compound, or the like.

Further, a crosslinking agent present as an emulsion in water and an organic solvent mixed with water is also preferable.

In the hydrophilic swelling layer used in the present invention, it is preferable that the values of the water absorption, the water absorption, the initial elastic modulus and the water swelling calculated in accordance with the following methods are in specific ranges.

First, the water absorption is represented by the following equation.

Water absorption (%) = water absorption (g / m ² ) / hydrophilic swelling layer thickness (g / m ² ) × 100 where the water absorption means a value according to the following definition:
Each value is measured by the following measurement method.

Water absorption (g / m ² ) = W _WET −W _DRY W _DRY : Weight in dry state (g / m ² ) W _WET : Weight (g) after immersion in water at 25 ° C. × 10 minutes
/ M ² ) [Method of measuring water absorption] A non-image area of a lithographic printing plate to be measured is cut into a predetermined area and immersed in purified water at 25 ° C. After immersion for 10 minutes, excess liquid adhering to the front and back surfaces of the hydrophilic swelling layer of the printing plate was quickly wiped off with “Hize Gauze” (cotton cloth: manufactured by Asahi Kasei Kogyo Co., Ltd.).
The swelling weight W _WET of the printing plate is weighed. Thereafter, the printing plate is dried in an oven at 60 ° C. for about 30 minutes, and the dry weight W _DRY is weighed.

The water absorption of the non-image area composed of the hydrophilic swelling layer of the present invention is 1 from the viewpoint of ink repulsion and form retention.
５０50 g / m ² , preferably 2-40 g / m ^2
2 , more preferably 3 to 30 g / m ² . The water absorption of the non-image area composed of the hydrophilic swelling layer is 1 g /
If it is less than m ² , the ink resilience will be insufficient and background smear will easily occur during printing. On the other hand, if the water absorption exceeds 50 g / m ² , the form retention will tend to be significantly reduced.

The hydrophilic swelling layer used in the present invention may preferably have a water absorption of 10 to 2000%, and more preferably 50 to 1700% from the viewpoint of ink resilience and shape retention. More preferably 50 to
700%. If the water absorption is less than 10%, the resilience of the ink tends to be extremely reduced, and defects such as pinholes are likely to occur during coating. If it exceeds 2000%, the shape retention tends to be extremely reduced.

[0171] The thickness of the hydrophilic swelling layer in the present invention means a value measured by a gravimetric method after peeling off the coating layer of the hydrophilic swelling layer of a dried lithographic printing plate precursor coated on a substrate. . The thickness of the hydrophilic swelling layer is measured according to the following formula and according to the following measurement method.

Thickness of hydrophilic swelling layer (g / m ² ) = (W−W 0) / α W: dry weight of lithographic printing plate precursor (g) W 0: after peeling off hydrophilic swelling layer from W Dry weight (g) α: Measuring area of photosensitive lithographic printing plate precursor (m ² ) [Method of measuring hydrophilic swelling layer thickness] After cutting a lithographic printing plate precursor to be measured into a predetermined area α, 60 ° C. After drying in an oven for about 30 minutes, the dry weight W is weighed. Thereafter, the original plate is immersed in purified water to swell the hydrophilic swelling layer, and the swelling layer is peeled off using a scraper or the like. The original plate from which the hydrophilic swelling layer was peeled off was dropped again at 60 ° C
After drying in an oven for about 30 minutes, the dry weight W0 is weighed.

The hydrophilic swelling layer used in the present invention has a thickness of
It can be used at 0.1 to 100 g / m ² ,
From the viewpoints of ink repellency and shape retention, the amount is preferably 0.2 to 10 g / m ² . Its thickness is 0.1g / m
^If it is less than ² , the ink rebound tends to be extremely reduced, and defects such as pinholes are likely to occur during coating. If it is 10 g / m ² or more, the shape retention during water swelling tends to deteriorate, which is economically disadvantageous.

The hydrophilic swelling layer of the present invention preferably has rubber elasticity. That is, the initial elastic modulus of the hydrophilic swelling layer calculated by the following method is preferably within a specific range.

[Method of Measuring Initial Elastic Modulus] A solution having the same composition as the portion corresponding to the non-image area of the lithographic printing plate is spread on a Teflon dish and dried at 60 ° C. for 24 hours. The obtained dried and cured film is 40 mm long using a razor blade or the like.
The test piece is cut into a rectangular test piece having a width of 1.95 mm and a thickness of about 0.2 mm.

The obtained test piece was heated at 25 ° C. before measurement.
After being left for 24 hours or more in an environment of 50% RH and adjusting the humidity, the thickness is measured with a micro gauge, and the initial elastic modulus is measured under the following tensile conditions. Data processing is JIS K
6301.

Tensile speed: 200 mm / min. Distance between chucks: 20 mm. Number of repetitions: four. Measuring machine: "RTM-100" (manufactured by Orientec Co., Ltd.) The initial elastic modulus of the hydrophilic swelling layer is 0. .01 to 10 kgf /
mm ² is preferable from the viewpoint of ink repulsion and form retention, and is preferably 0.01 to 5 kgf / mm.
² is more preferable, and the range of 0.01 to ² kgf / mm ² is further preferable. Initial elastic modulus is 0.01kgf /
When it is less than ² mm ^2, the shape retention of the hydrophilic swelling layer is reduced, the printing durability is poor, and the initial elastic modulus is 10 kgf / m.
When it is larger than m ² , the ink rebound tends to be extremely reduced.

The hydrophilic swelling layer used in the present invention preferably has a water swelling ratio calculated according to the following method in a specific range. The water swelling ratio (%) is represented by the following equation.

Water swelling ratio (%) = (Θ _WET -Θ _DRY ) / Θ _DRY × 100 Θ _DRY : Thickness (μm) of hydrophilic swelling layer composed of non-image area in dry state Θ _WET : Non-swelling state Thickness (μm) of hydrophilic swelling layer composed of image area [Method of measuring water swelling rate (A)] Cut and slice so that a portion including a non-image area of a lithographic printing plate to be measured has a cross section. Is prepared. After vacuum-drying this section at room temperature for one day and night, the thickness of the hydrophilic swelling layer at the site is observed with an optical microscope, and this is defined as _ΘDRY (μm). The observation with an optical microscope is performed quickly in an environment of 23 ° C. and 20% RH.

Further, an excess water droplet was placed on this lithographic printing plate section, and the section was observed with an optical microscope in a state where the hydrophilic swelling layer was sufficiently swollen with water, and the thickness of the hydrophilic swelling layer at the site was read.と_する_WET (μm).

[Method of measuring water swelling ratio (B)] The non-image area of the lithographic printing plate to be measured was exposed to an OsO ₄ aqueous solution for one day and night, and the hydrophilic swelling layer was fixed with OsO ₄ . An ultrathin section is prepared by cutting with a microtome so that a predetermined portion has a cross section. The thickness of the hydrophilic swelling layer at the site is observed with a transmission electron microscope (TEM) at a magnification of about 10,000 to 50,000 times, and this is defined as Θ _DRY (μm).

On the other hand, the planographic printing plate to be measured is
The sO ₄ 2 to 3 days immersed hydrophilic swellable layer in the aqueous solution is solidified / fixed water swollen state. An ultra-thin section is prepared by cutting with a microtome so that a predetermined portion has a cross section, and the thickness of the hydrophilic swelling layer of the portion is determined by a transmission electron microscope (TEM) at a magnification of about 10,000 to 50,000 times. And read this and call it Θ _{WE T}
(Μm).

The water swelling ratio of the non-image area (ink repelling portion) composed of the hydrophilic swelling layer of the present invention is preferably 100 to 1000% from the viewpoint of ink repellency and form retention, and is preferably 500 to 1700. %, More preferably 50%
More preferably, it is in the range of 700%. When the water swelling ratio is less than 10%, the ink resilience of the non-image portion decreases, while when the water swelling ratio of the non-image portion exceeds 2000%, the non-image portion has poor shape retention and printing. Sometimes, the non-image area is easily damaged.

The hydrophilic swelling layer of the present invention may use a hydrophobic polymer. As the hydrophobic polymer, those mainly composed of an aqueous emulsion are preferably used.

The aqueous emulsion referred to in the present invention means an aqueous solution of a hydrophobic polymer suspension in which particles comprising fine polymer particles and, if necessary, a protective layer surrounding the particles are dispersed in water.

That is, it means a self-emulsifying or forced emulsifying aqueous solution basically composed of emulsion particles composed of polymer particles as a dispersoid, a protective layer formed as required, and a dilute aqueous solution as a dispersion medium. Specific examples of the aqueous emulsion used in the present invention include a vinyl polymer latex, a conjugated diene polymer latex, and an aqueous or water-dispersed polyurethane resin.

Among these aqueous emulsions, hydrophobic polymers particularly preferably used in the present invention include styrene / butadiene-based, acrylonitrile / butadiene-based and
Latexes containing conjugated diene compounds such as methyl methacrylate / butadiene and chloroprene are mentioned.

The hydrophilic swelling layer of the present invention may be formed by mixing the above-mentioned hydrophilic polymer and hydrophobic polymer, cross-linking or pseudo-cross-linking as necessary, and forming a laminate on a substrate. For the crosslinking, it is preferable to carry out a crosslinking reaction using a reactive functional group of the hydrophilic polymer and the hydrophobic polymer. The cross-linking reaction may be covalent cross-linking or ionic cross-linking.

As a method of mixing the hydrophilic polymer and the hydrophobic polymer constituting the hydrophilic swelling layer of the present invention, a method of kneading using a mixer such as a roll mixer such as a three-roller, a kneader, a homogenizer, a ball mill It is preferably mixed by a known method used when producing a paint or a putty, such as a method of wet mixing and dispersing using a disperser.

As a method for forming the hydrophilic swelling layer of the present invention, since an aqueous emulsion is preferably used as the hydrophobic polymer, each component (hydrophilic polymer, hydrophobic polymer, etc.) is mixed in an aqueous solution system, A method in which a crosslinking agent is added as necessary is preferable from the viewpoint of realizing a homogeneous structure and improving ink resilience.

Therefore, it is particularly preferable to use a water-soluble polyfunctional compound as the crosslinking agent. That is, it is preferable to use a water-soluble polyepoxy compound, polyamine compound, melamine compound, or the like.

In the hydrophilic swelling layer used in the present invention, in addition to the above-mentioned hydrophilic polymer, hydrophobic polymer and optionally a crosslinking agent, a known antioxidant usually added in a rubber composition. , An antioxidant, an antiozonant, an ultraviolet absorber, a dye, a pigment, and a plasticizer.

For the purpose of improving the adhesion to the lower layer, etc.,
Known silane coupling agents and isocyanate compounds,
It is also possible to add a catalyst or the like, or to provide an adhesive layer between the substrate and the substrate.

Further, the hydrophilic swelling layer used in the present invention can contain trace amounts of various additives such as dyes and pigments, pH indicators, leuco dyes, surfactants and organic acids.

The substrate of the lithographic printing plate used in the present invention is not limited at all, except that it is required to have flexibility that can be attached to a normal lithographic printing machine and to withstand a load applied during printing. Representative substrates include metal plates such as aluminum, copper, and iron, plastic films such as polyester films and polypropylene films, coated paper, and rubber sheets. Further, these substrates may be a composite of the above materials.

The surface of the substrate may be subjected to various surface treatments such as an electrochemical treatment, an acid-base treatment, and a corona discharge treatment for the purpose of improving plate inspection and adhesion.

Further, it is also possible to form a primer layer on such a substrate by applying a coating or the like for the purpose of improving adhesiveness or preventing halation, thereby forming a substrate. As the primer layer used in the present invention, for example, in addition to those containing an epoxy resin as shown in JP-B-61-54219, polyurethane resins, phenol resins,
Acrylic resin, alkyd resin, polyester resin, polyamide resin, melamine resin, urea resin, benzoguanamine resin, vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, polyvinyl butyral resin, ethylene-vinyl acetate copolymer, polycarbonate resin, poly An acrylonitrile-butadiene copolymer, a polyether resin, a polyether sulfone resin, milk casein, gelatin and the like can be mentioned. These resins can be used alone or in combination of two or more.

Of these, polyurethane resins, polyester resins, acrylic resins, epoxy resins, and urea resins are preferably used alone or in combination of two or more. Further, as the anchoring agent constituting the primer layer, for example, a known adhesive such as a silane coupling agent can be used, and an organic titanate is also effective.

Further, a surfactant may optionally be added for the purpose of improving coatability. The composition for forming the above primer layer is prepared as a composition solution by dissolving in a suitable organic solvent such as DMF, methyl ethyl ketone, methyl isobutyl ketone, and dioxane. A primer layer is formed by uniformly applying the composition solution on a substrate and heating it at a required temperature for a required time.

The thickness of the primer layer is 0.5 to 50 g / m
² is preferred, and more preferably 1 to 10 g / m ² . When the thickness is less than 0.5 g / m ² , the effect of blocking morphological defects and chemical adverse effects on the substrate surface is low, and the thickness is 50 g / m ^2.
If the thickness is larger than m ^2, it is disadvantageous from an economic viewpoint, so the above range is preferable.

Next, a method for making a laser-sensitive lithographic printing plate precursor according to the present invention will be described. In the present invention, the laser sensitivity means that an image can be formed in a heat mode. In other words, the part irradiated with the laser
The hydrophilic swelling layer becomes insoluble in the solvent and adheres to the lower layer of the hydrophilic swelling layer to form a non-image area (a dampening water film is formed during printing and becomes an ink repellent area), while laser irradiation is not performed. By dissolving and removing the portion in an appropriate solvent, the lower layer of the hydrophilic swelling layer is exposed to form an image portion (a dampening solution does not adhere at the time of printing and becomes an ink-coated portion). Such solvents can include organic solvents, water, or mixtures thereof. From the viewpoint of odor problems during development and handling problems such as disposal, it is preferable that the solvent that dissolves the laser non-irradiated portion of the hydrophilic swelling layer is water.

The printing plate can be obtained by subjecting the laser-sensitive lithographic printing plate precursor of the invention to imagewise exposure using a laser. Examples of the laser preferably used include, for example, a semiconductor laser, a YAG laser, an argon ion laser, a helium neon laser, a helium-cadmium laser, and a carbon dioxide gas laser, and are not particularly limited. Lasers are preferred. As the power output, a laser having a power output of 40 to 50,000 mW is preferably used. Among them, a semiconductor laser having a power of 500 to 30,000 mW is preferably used from the viewpoint of efficiently performing heat mode recording. Usually, the diameter of the ink-repellent convex portion formed by one laser irradiation is 3
About 100 μm.

Next, a printing method using a printing plate obtained from the laser-sensitive planographic printing plate precursor of the invention will be described.

For lithographic printing using the laser-sensitive lithographic printing plate precursor according to the invention, a known lithographic printing machine is used.
That is, sheet-fed and rotary printing machines of the offset and direct printing type are used.

The lithographic printing plate precursor of the present invention is drawn with a laser beam, and the soluble portion of the hydrophilic swelling layer is dissolved with a solvent.
After removal and image formation, they are mounted on a plate cylinder of a lithographic printing press. The plate is supplied with ink from an inking roller in contact. The non-image area having the hydrophilic swelling layer on the plate swells with the dampening water supplied from the dampening water supply device and repels the ink. On the other hand, the image portion receives ink and supplies the ink to the surface of the offset blanket cylinder or the surface of the printing medium to form a printed image.

The fountain solution used for printing a lithographic printing plate having a hydrophilic swelling layer, which is drawn by the image forming method of the present invention, may be an etchant used in normal lithographic printing. Although possible, pure water without any additives can be used.

Hereinafter, the present invention will be described in more detail with reference to examples.

[0208]

EXAMPLES (Synthesis Example 1) A stirring rod, a thermometer, and a nitrogen inlet tube were attached to a 1-liter four-neck separable flask.
An aqueous solution in which 100 g of N-vinylacetamide was dissolved in 280 g of deionized water was charged. Dissolve dissolved oxygen by introducing nitrogen gas for about 10 minutes,
° C, and 2,2'-azobis-
20 g of a 5% aqueous solution of 2-aminopropane dihydrochloride was added, and a polymerization reaction was carried out for about 10 hours. The viscosity of each of the obtained polymers was 235 cps as measured by a B-type viscometer (0.2% aqueous solution: 30 ° C., rotation speed: 20 rpm).

(Synthesis Example 2) To 60 g of vinyl acetate and 40 g of methyl acrylate, 0.5 g of benzoyl peroxide was weighed as a polymerization initiator, and these were mixed with 3 g of partially saponified polyvinyl alcohol as a dispersion stabilizer and NaCl 10
g in 300 ml of water.

This dispersion was stirred at 65 ° C. for 6 hours to carry out suspension polymerization. The methyl acrylate component of the obtained copolymer was identified by NMR spectrum as a result of 48 mol%.
Met. The intrinsic viscosity in a benzene solution at 30 ° C. was 2.10.

Next, 8.6 g of the copolymer was added to 200 g of methanol, 10 g of water and 40 ml of 5N NaOH.
And suspended by stirring at 25 ° C.
After performing the saponification reaction for 1 hour, the temperature was raised to 65 ° C., and the saponification reaction was further performed for 5 hours.

The obtained saponification reaction product was sufficiently washed with methanol and freeze-dried. Its saponification degree was 98.3 mol%, and as a result of measurement of an infrared absorption spectrum, 340
An absorption attributed to a broad -OH group was observed at around 0 cm ^-1 and a strong absorption attributed to a -COO ^- group was observed at 1570 cm ^-1 .

(Example 1) The following primer layer coating solution was applied to a degreased aluminum plate (manufactured by Sumitomo Light Metal Co., Ltd.) having a thickness of 0.24 mm, and then heated and cured at 200 ° C. for 2 minutes to obtain 1 An ink deposit having a thickness of 0.5 g / m ² was applied.

<Primer layer coating solution (parts by weight)> (1) Epoxy / phenol resin “Cancoat 90t-
25-3094 "(manufactured by Kansai Paint Co., Ltd.): 15 parts by weight (2) Victoria Pure Blue BOH naphthalenesulfonic acid: 0.1 part by weight (3) Dimethylformamide: 85 parts by weight Next, a heat-sensitive cured layer having the following composition After applying the coating liquid, 13
Heat treatment was performed at 0 ° C. for 1 minute to form a thermosetting layer having a thickness of ² g / m ² .

<Coating solution of thermosetting layer (parts by weight)> (1) Allyl urethane compound obtained by reacting hexamethylene diisocyanate / ethylene glycol / allyl alcohol at a molar ratio of 3/2/2: 50 parts by weight ( 2) Epoxy acrylate “DA-314” (manufactured by Nagase Kasei Co., Ltd.): 15 parts by weight (3) Pentaerythritol tetrathioglycol: 25 parts by weight (4) Infrared absorbing dye “PA-1005” (Mitsui Toatsu Chemical ( (5) Benzoyl peroxide: 2 parts by weight (6) Organic peroxide "Perhexa 3M" (manufactured by NOF Corporation): 3 parts by weight (7) Methyl ethyl ketone: 100 parts by weight ( 8) 1,4-dioxane: 300 parts by weight Next, after applying the following hydrophilic swelling layer coating liquid, 120
Heat treatment was performed at 20 ° C. for 20 minutes to apply a hydrophilic swelling layer having a thickness of 3 g / m ² . When the water absorption and the water swelling ratio were measured, they were 300% and 350%, respectively.

<Coating Solution for Hydrophilic Swelling Layer (Parts by Weight)> (1) Copolymer of Synthesis Example 1: 90 parts by weight (2) Water-soluble melamine formaldehyde resin: 10 parts by weight (3) Ethanol: 100 parts by weight ( 4) Purified water: 800 parts by weight The surface of the obtained laser-sensitive lithographic printing plate precursor was irradiated with a semiconductor laser under the following conditions. This printing plate precursor was washed with water for about 1 minute, left to stand, and air-dried to obtain a printing plate. In the portion corresponding to the laser irradiation, the hydrophilic swelling layer remains,
In the unirradiated portion, the hydrophilic swelling layer was completely eluted, and the ink-coated layer was exposed.

Laser output: 1 W (830 nm) Spot diameter: 6 μm Pulse width: 10 μsec The obtained printing plate is printed on a sheet-fed offset printing machine “Sprint 2”.
5: Komori Corporation Co., Ltd. "and supplying high quality paper (6
2.5 kg / chrysanthemum).

At the time when about 1,000 sheets were printed, no ink stain was generated on each plate, and a clear printed matter having a sufficient contrast was obtained.

In the rub resistance test, no damage was observed on the plate surface, and the level of the rub resistance test was ○.

The evaluation of the rub resistance was carried out by the following method.

<Scratch resistance test> Three pieces of white cloth for triangular width cut into 6 x 6 cm pieces were stacked, and a 5 x 5 x 2.5 cm rectangular parallelepiped (made of iron, about 500 g) was placed thereon, and the printing was indicated with purified water. The plate was rubbed 500 times. The plate surface after the test is visually observed. When the plate surface has no scratches, ○, when the plate surface is slightly scratched (a level usable for a small number of copies), 印刷,
The case where peeling was seen on the plate surface was evaluated as x.

(Example 2) The following primer layer coating solution was applied to a degreased aluminum plate (manufactured by Sumitomo Light Metal Co., Ltd.) having a thickness of 0.24 mm, and then cured by heating at 200 ° C. for 2 minutes. An ink deposit having a thickness of 0.5 g / m ² was applied.

<Primer layer coating liquid (parts by weight)> (1) Epoxy phenol resin “Cancoat 90t-25-3094” (manufactured by Kansai Paint Co., Ltd.): 15 parts by weight (2) Victoria Pure Blue BOH naphthalenesulfonic acid : 0.1 part by weight (3) Dimethylformamide: 85 parts by weight Next, after applying the following hydrophilic swelling layer coating solution, 180 parts by weight
Heat treatment was performed at 20 ° C. for 20 minutes to apply a hydrophilic swelling layer having a thickness of ² g / m ² . When the water absorption and the water swelling ratio were measured, they were 300% and 350%, respectively.

<Hydrophilic Swelling Layer Coating Solution (Parts by Weight)> (1) 90 parts by weight of the copolymer of Synthesis Example 2 (2) 10 parts by weight of glyoxal (3) 100 parts by weight of ethanol (4) 800 parts by weight of purified water Next, after applying a thermosetting layer coating solution having the following composition, 12
Heat treatment was performed at 0 ° C. for 3 minutes to apply a thermosetting layer having a thickness of 3 g / m ² .

<Coating solution for thermosetting layer (parts by weight)> (1) Polyester polyol of adipic acid and hexane-1,6-diol, 2,2-dimethylpropane-1,3-diol and isophorone diisocyanate (2) Allyl urethane compound obtained by reacting hexamethylene diisocyanate / ethylene glycol / allyl alcohol at a molar ratio of 3/2/2: 70 parts by weight (3 ) Epoxy acrylate "DA-314" (manufactured by Nagase Kasei Co., Ltd.): 20 parts by weight (4) Pentaerythritol tetrathioglycol: 37 parts by weight (5) Infrared absorbing dye "PA-1005" (Mitsui Toatsu Chemical ( 5 parts by weight (6) Benzoyl peroxide: 2 parts by weight (7) Organic peroxide "Perhexa 3M" (Nippon Oil Co., Ltd.) (8) Diphenyliodonium triflate: 3 parts by weight (9) Methyl ethyl ketone: 100 parts by weight (10) 1,4-dioxane: 250 parts by weight The obtained laser-sensitive lithographic printing plate precursor. Was irradiated with a semiconductor laser under the following conditions. A developing pad (3) in which this printing plate precursor was impregnated with a developing solution having the following composition:
(Manufactured by M Co., Ltd.), rubbed lightly, developed, left to stand, and air-dried to obtain a printing plate.

In the part corresponding to the laser irradiation, the heat-sensitive cured layer remained, and in the unirradiated part, the heat-sensitive cured layer was completely eluted, exposing the hydrophilic swelling layer.

Laser output: 1 W (830 nm) Spot diameter: 6 μm Pulse width: 10 μsec The obtained printing plate is printed on a sheet-fed offset printing machine “Sprint 2”.
5: manufactured by Komori Corporation Co., Ltd., and while supplying commercially available purified water as a dampening solution, a high-quality paper (62.5
kg / chrysanthemum).

At the time when about 1000 sheets were printed, no ink stain was generated on each plate, and a clear printed matter having a sufficient contrast was obtained. Also, in the rub resistance test, no damage was seen on the plate surface, and the level of the rub resistance test was ○.

(Example 3) The lithographic printing plate used in Example 2 and a normal PS plate (FNS; manufactured by Fuji Photo Film Co., Ltd.)
Was exposed and developed to form a printing plate, which was mounted on the same plate cylinder, and printing was performed in the same manner as in Example 2 while supplying commercially available purified water as a dampening solution.

When the supply amount of the dampening solution is increased from the standard condition, the ink density of the image area is extremely reduced in the portion where the PS plate is used, and poor ink deposition due to so-called "water loss" occurs. did. On the other hand, in the part using the lithographic printing plate used in Example 2, the degree of incomplete deposition was slight.

Further, when the supply amount of the dampening solution was reduced from the standard condition, ink staining occurred on the entire surface of the portion using the PS plate. On the other hand, in the portion using the lithographic printing plate used in Example 1, good printed matter was obtained. The supply amount of dampening water was relatively compared with the dial scale value of the printing press. Table 1 shows the evaluation results.

[0232]

[Table 1]

[0233]

According to the present invention, it is possible to draw with a laser, and in the printing process, the ink has a high repulsion, the permissible range of dampening water is wide, and a good printed image can be obtained by using pure water as dampening water. Can be obtained, so that a fountain solution without IPA can be used, and a laser-sensitive lithographic printing plate having excellent printing durability can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/11 501 G03F 7/11 501

Claims (7)

[Claims] 1. A lithographic printing plate precursor comprising at least a hydrophilic swelling layer and a thermosetting layer adjacent to each other on a substrate, wherein the thermosetting layer comprises: (a) a substance which absorbs light and generates heat;
A laser-sensitive lithographic printing plate precursor comprising (b) a compound having an ethylenically unsaturated group, (c) a compound having a thiol group, and (d) a substance that generates a radical by heating. 2. The laser sensitivity according to claim 1, wherein the compound (b) containing an ethylenically unsaturated group is a compound having two or more ethylenically unsaturated groups in one molecule. Lithographic printing plate precursor. 3. The laser-sensitive lithographic printing plate precursor according to claim 1, wherein the compound (c) having a thiol group is a compound having two or more thiol groups in one molecule. 4. The laser-sensitive lithographic printing plate precursor according to claim 1, wherein the heat-sensitive cured layer contains (f) an epoxy compound. 5. The lithographic printing plate precursor as claimed in claim 1, wherein the compound (b) having an ethylenically unsaturated group is a compound further having a hydroxyl group. 6. The heat-sensitive cured layer contains (e) a substance which generates an acid upon heating.
The lithographic printing plate precursor according to any one of the above. 7. The laser-sensitive lithographic printing plate precursor according to claim 1, wherein (a) the substance that absorbs light and generates heat has an absorption in a wavelength range of 700 to 1100 nm.