JP4715269B2 - Direct drawing type waterless planographic printing plate precursor - Google Patents

Description

  The present invention relates to a waterless lithographic printing plate precursor, and more particularly to a direct-drawing waterless lithographic printing plate precursor that can be directly made with a laser beam.

  The so-called direct drawing type plate making, which does not use a plate-making film directly from a manuscript, is a simple drawing that does not require skill, quickness to obtain a printing plate in a short time, quality from various systems Taking advantage of features such as rationality that can be selected according to cost, the company has begun to enter not only the light printing industry but also general offset printing and flexographic printing.

  Particularly recently, various types of direct-drawing lithographic printing plates have been developed due to rapid progress in output systems such as prepress systems, imagesetters, and laser printers.

  These direct-drawing lithographic printing plates are classified according to the plate making method: a method of irradiating with laser light, a method of writing with a thermal head, a method of partially applying a voltage with a pin electrode, a silicone rubber layer or an ink-implanted layer by inkjet The method of forming is mentioned. Among them, the method using laser light is superior to other methods in terms of resolution and plate making speed, and there are many types.

  This printing plate using laser light is further divided into two types: a photon mode by photoreaction and a heat mode in which photothermal conversion is performed to cause a thermal reaction. In particular, the heat mode method has the advantage that it can be handled in a bright room. The usefulness of semiconductor lasers as light sources has recently been reviewed due to rapid progress.

  The following proposals have been made for the heat-mode direct-drawing waterless planographic printing plate.

  For example, a thermal destruction direct-drawing waterless lithographic printing plate (for example, see Patent Documents 1 and 2) using laser light as a light source is disclosed.

  The heat sensitive layer of the printing plate precursor mainly uses carbon black as a laser light absorbing compound and nitrocellulose as a thermal decomposition compound. The carbon black absorbs the laser beam to be converted into thermal energy, and the heat sensitive layer is destroyed by the heat. Finally, by removing this portion by development, the silicone rubber layer on the surface is peeled off at the same time to form an image portion.

  However, this thermal destruction printing plate forms an image by destroying the heat-sensitive layer, so that the cell depth of the image area becomes deep, the ink deposition property at a minute halftone dot is poor, and the ink mileage There was a problem of being bad. Furthermore, in order to make the heat sensitive layer easily destroyed by heat, a crosslinked structure is formed, and there is a problem that the printing durability of the printing plate is poor. Further, this printing plate has a low sensitivity, and there is a problem that a high laser beam intensity is required to destroy the heat-sensitive layer.

  As a method of improving such a problem, the image is formed by having a heat-sensitive layer and a silicone rubber layer on the substrate and reducing the adhesion between the heat-sensitive layer and the silicone rubber layer by converting laser light into heat. A direct-drawing waterless lithographic printing original plate that can be formed and a method of providing a heat insulating layer between a substrate and a heat-sensitive layer are disclosed (for example, see Patent Documents 3 and 4).

  In recent years, there is a need for plate inspection that reads the reflection density of a printing plate with a densitometer (machine reading). However, the conventional printing plate has a problem that the halftone dot area ratio of the printing plate cannot be measured with sufficient accuracy in practice with a reflection densitometer or the like (insufficient machine readability of halftone dots). In addition, there is a problem that the printing plate is easily scratched during handling, ink is deposited on the scratch, and the non-image area is stained. As a method for improving these problems, a method is disclosed in which a heat insulating layer having a transmittance of 15% or less for all wavelengths of light having a wavelength of 400 to 650 nm is provided (for example, see Patent Document 5).

Although various improvements have been made in this way, conventionally known printing plates tend to have printing scratches on the printing plate when handling the printing plate, washing the printing plate, and printing, and the ink is attached to the scratches. There was a problem that the non-image area became dirty. As a method for solving this problem, a method for improving scratch resistance by providing a heat insulating layer with flexibility has been disclosed (for example, see Patent Document 6). However, when the heat-insulating layer is softened, the scratch resistance is improved, but the scratches generated during the handling and printing of the plate are not completely eliminated, and further, the development latitude is narrowed. In particular, when an automatic processor is used, good image reproducibility cannot be obtained at a high development speed, and it is difficult to achieve both scratch resistance and printing durability and a wide development latitude.
JP-A-6-55723 (page 2-4) JP-A-7-164773 (page 4-5) JP 2000-330266 A (page 3-8) JP-A-11-268436 (page 3-15) JP-A-2004-199016 (page 2-7) JP 2004-334025 A (page 3-10)

  An object of the present invention is to provide a direct-drawing waterless lithographic printing plate precursor having excellent scratch resistance and printing durability and having a wide development latitude.

  The direct-drawing waterless planographic printing plate precursor of the present invention has the following characteristics in order to solve the above problems. That is, “a direct-drawing waterless lithographic printing plate precursor having at least a heat insulating layer, a heat sensitive layer, and a silicone rubber layer in this order on a substrate, the heat insulating layer comprising at least a polyurethane resin, an active hydrogen group-containing aromatic compound, and The metal chelate compound is contained, the content of the polyurethane resin is 40% to 55% with respect to the weight of the heat insulation layer, and the active hydrogen group-containing aromatic compound and the metal chelate compound with respect to the weight of the polyurethane resin in the heat insulation layer A direct-drawing waterless lithographic printing plate precursor characterized in that the ratio of the sum of weights (polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) is 1.5 to 3.0. is there.

  According to the present invention, a direct-drawing waterless lithographic printing plate precursor having excellent scratch resistance and printing durability and having a wide development latitude can be obtained.

  The present invention is described in detail below.

  The direct-drawing waterless lithographic printing plate of the present invention is a direct-drawing waterless lithographic printing plate precursor having at least a heat insulating layer, a heat-sensitive layer, and a silicone rubber layer in this order on a substrate, and the heat insulating layer is at least a polyurethane. A resin, an active hydrogen group-containing aromatic compound and a metal chelate compound, the content of the polyurethane resin is 40% to 55% based on the weight of the heat insulating layer, and the active hydrogen relative to the weight of the polyurethane resin in the heat insulating layer Direct drawing characterized in that the ratio of the sum of the weight of the group-containing aromatic compound and the metal chelate compound (polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) is 1.5 to 3.0 A waterless lithographic printing plate precursor.

  First, the heat insulation layer in the direct-drawing waterless planographic printing plate precursor of the present invention will be described. The heat insulation layer in the present invention contains at least a polyurethane resin, an active hydrogen group-containing aromatic compound and a metal chelate compound.

  In the present invention, the polyurethane resin serves as a binder polymer for imparting film formability, and as a component for maintaining the scratch resistance and printing durability, which are the properties necessary for flexibility and the printing plate of the heat insulating layer. Included in the layer. As the polyurethane resin, those generally used obtained from polyisocyanates and polyhydric alcohols can be used. Examples of polyisocyanates include, but are not limited to, paraphenylene diisocyanate, toluylene diisocyanate, diphenylmethane diisocyanate, tolidine diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, glycerin, trimethylolpropane, and the like. It is not limited.

  It is important that the content of these polyurethane resins is 40 to 55% with respect to the weight of the heat insulating layer. When the content of the polyurethane resin is less than 40%, the scratch resistance is lowered. On the other hand, if it exceeds 55%, the image reproducibility is adversely affected and the development latitude becomes narrow.

  In addition, the polyurethane resin may be extracted by the heat-sensitive layer solvent during coating of the heat-sensitive layer, but the proportion of the polyurethane resin in the component extracted by the heat-sensitive layer solvent affects the image reproducibility, so this proportion is specified. It is preferable that it exists in the range. The ratio of the polyurethane resin in the heat insulation layer extract by the heat sensitive layer solvent can be specified by an infrared transmission spectrum using the FT-IR method. Below, the method of measuring the extract extracted from the heat insulation layer with the heat sensitive layer solvent in the direct drawing type waterless planographic printing plate precursor of the present invention using an infrared spectrometer (FT-IR method) will be described.

  Any infrared spectrometer may be used as long as it can measure an infrared transmission spectrum using the FT-IR method.

  Infrared transmission spectra are susceptible to atmospheric water vapor and carbon dioxide. Therefore, 1) a method of measuring the infrared absorption spectrum by replacing the inside of the sample chamber with nitrogen gas, and 2) a method of subtracting the previously measured water vapor and carbon dioxide spectra from the infrared transmission spectrum of the sample. It is desirable to remove the effects of water vapor and carbon dioxide in the atmosphere.

When measuring the extract extracted from the heat insulation layer with the heat-sensitive layer solvent using an infrared spectrometer (FT-IR method), it is preferable to carry out under the conditions of resolution: 4 cm ⁻¹ or more and integration: 64 times or more. . By performing measurement under these conditions, it is not possible to detect what is supposed to be detected, and the detection limit is not exceeded.

  The method of extracting the extract from the heat insulating layer with the heat sensitive layer solvent is as follows. First, the heat insulating layer is immersed in a heat-sensitive layer solvent to be used under predetermined conditions. Next, the heat-sensitive layer solution containing the extract is distilled off to some extent. As a method for distilling off, any method may be used as long as it is a method capable of distilling only the heat-sensitive layer solvent, such as distilling with an evaporator or distillation. Further, the amount of the heat-sensitive layer solvent to be distilled off is not limited to the complete extraction, but may be any amount as long as the extract is dissolved in the heat-sensitive layer solvent. Thereafter, a heat-sensitive layer solvent containing an extract obtained by distilling a certain amount is applied to the substrate. The substrate to be used may be any substrate as long as the infrared transmission spectrum using the FT-IR method can be measured, and any of known wafers, metals, films, and the like can be used. An infrared transmission spectrum is measured using an infrared spectrometer for a sample in which a heat-sensitive layer solvent containing an extract obtained by distilling a certain amount is applied to a substrate. The measurement conditions at this time are the above-mentioned conditions.

The resulting infrared transmission spectra, the absorption band derived from the carbonyl group of the polyurethane resin is a heat-insulating layer component in the vicinity of 1715 cm ^-1, an aromatic having active hydrogen group-containing aromatic compound of the insulating layer component in the vicinity of 1510 cm ^-1 It has an absorption band derived from the carbon-carbon bond of the ring. When there is no compound having a carbonyl group in addition to the polyurethane resin in the heat insulation layer component, and there is no compound having an aromatic ring other than the active hydrogen group-containing aromatic compound, extraction is performed with a heat-sensitive layer solvent when applying the heat-sensitive layer. It is possible to reproduce the heat insulating layer extract to be expressed and to express the ratio of the polyurethane resin in the extract based on the aromatic ring of the active hydrogen group-containing aromatic compound.

In the direct drawing type waterless planographic printing plate precursor of the present invention, an infrared transmission spectrum measured using an infrared spectrometer (FT-IR method) in a heat insulating layer extract with a heat sensitive layer solvent, a peak at 1735 cm ⁻¹ . The value obtained by dividing the intensity by the peak intensity at 1510 cm ⁻¹ (represented as (d1735 / d1510)) is polyurethane based on the active hydrogen group-containing aromatic compound among the uncured components of the heat insulating layer extracted by the heat-sensitive layer solvent. It represents the proportion of resin. (D1735 / d1510) is preferably 1.5 to 2.5. When (d1735 / d1510) is 1.5 to 2.5, the ratio of the polyurethane resin in the extract extracted with the heat-sensitive layer solvent is within the appropriate range, and the development is good without adversely affecting the image reproducibility. There is no development failure during processing, and a wide development latitude can be obtained.

  The polyurethane resin has a ratio of the sum of the weights of the active hydrogen group-containing aromatic compound and the metal chelate compound to the weight of the polyurethane resin in the relationship of the weight ratio between the active hydrogen group-containing aromatic compound and the metal chelate compound described later ( It is important that polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) is 1.5 to 3.0. By maintaining this relationship, the image reproducibility and scratch resistance of the printing plate are improved. If it is less than 1.5, the active hydrogen group-containing aromatic compound and the metal chelate compound are excessively present and are extracted by the heat-sensitive layer solvent during coating of the heat-sensitive layer, which may adversely affect image reproducibility. If it exceeds 3.0, the curing reaction between the active hydrogen group-containing aromatic compound and the metal chelate compound is inhibited by the polyurethane, and the amount of the polyurethane resin extracted by the heat-sensitive layer solvent during coating of the heat-sensitive layer is increased, and the image reproducibility is increased. May adversely affect

  Moreover, in the heat insulation layer in this invention, it is also possible to mix and use another binder polymer with a polyurethane resin. Representative binder polymers include, but are not limited to, polyolefins, polystyrenes, vinyl polymers such as (meth) acrylic ester polymers, unvulcanized rubber, polyesters, and the like.

  In the present invention, the heat insulating layer contains an active hydrogen group-containing aromatic compound. Examples of the active hydrogen group-containing aromatic compound include a hydroxyl group-containing aromatic compound, an amino group-containing aromatic compound, a carboxyl group-containing aromatic compound, and a thiol group-containing aromatic compound. A hydroxyl group-containing aromatic compound is used. It is preferable.

  Furthermore, as the hydroxyl group-containing aromatic compound, a phenolic hydroxyl group-containing compound and an aromatic epoxy resin can be used in the present invention.

  Examples of the phenolic hydroxyl group-containing compound include the following compounds. Hydroquinone, catechol, guaiacol, cresol, xylenol, naphthol, dihydroxyanthraquinone, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, bisphenol A, bisphenol S, novolac resin, resole resin, resorcinbenzaldehyde resin, pyrogallol acetone resin, hydroxystyrene Examples of the polymer include copolymers and copolymers, rosin-modified phenol resins, epoxy-modified phenol resins, lignin-modified phenol resins, aniline-modified phenol resins, melamine-modified phenol resins, and bisphenols.

  Examples of the aromatic epoxy resin include the following compounds. Bisphenol A glycidyl ester, other bisphenol A type epoxy resins, bisphenol F diglycidyl ester, other bisphenol F type epoxy resins, bisphenol AD diglycidyl ester, other bisphenol AD type epoxy resins, terephthalic acid diglycidyl ester, glycidyl phthalimide, Dibromophenyl glycidyl ester, phenol novolac epoxy resin, cresol novolac epoxy resin, aniline and epichlorohydrin reacted, phenol and aniline co-condensed with formaldehyde, epoxidized novolac type resin, tolylene diisocyanate and Although what reacted glycidol etc. is mentioned, It is not limited to these.

  Examples of the amino group-containing aromatic compound include methyl p-aminobenzoate, ethyl p-aminobenzoate, methyl m-aminobenzoate, ethyl m-aminobenzoate, methyl 4-amino-3-methylbenzoate, 4- Ethyl amino-3-methylbenzoate, ethyl 3-amino-2-methylbenzoate, methyl 3-amino-2-methylbenzoate, ethyl 4-amino-2-chlorobenzoate, 4-amino-2-chlorobenzoate Acid methyl, ethyl 3-amino-4-chlorobenzoate, methyl 3-amino-4-chlorobenzoate, ethyl 4-amino-3-methoxybenzoate, methyl 4-amino-3-methoxybenzoate, 3-amino Ethyl-4-methoxybenzoate, methyl 3-amino-4-methoxybenzoate, metaphenylenediamine, diaminodiphenylmethane, diaminodiphe Rusurufon, di- amino diethyl methane, and the like.

  The carboxyl group-containing aromatic compound includes an aromatic ring substituted with at least one carboxyl group in the molecule. The aromatic ring is preferably an aryl group such as a phenyl group or a naphthyl group. The carboxyl group may be directly bonded to the aromatic ring or may be bonded through a joint. Examples of aromatic compounds having a carboxyl group include salicylic acid, 4-methylsalicylic acid, 6-methylsalicylic acid, 4-ethylsalicylic acid, 6-propylsalicylic acid, 6-laurylsalicylic acid, 6-stearylsalicylic acid, 4,6-dimethylsalicylic acid. P-oxybenzoic acid, 6-methyl-4-oxybenzoic acid, 2,6-dimethyl-4-oxybenzoic acid, 2,4-dioxybenzoic acid, 2,4-dioxy-6-methylbenzoic acid, 2 , 6-dioxybenzoic acid, 2,6-dioxy-4-methylbenzoic acid, 4-chloro-2,6-dioxybenzoic acid, 4-methoxy-2,6-dioxybenzoic acid, gallic acid, phloroglucincarboxylic Acid, 2,4,5-trioxybenzoic acid, m-galloyl gallic acid, tannic acid, m-benzoyl gallic acid, m- (p-) tolu Gallic acid, protocatechuic oil-gallic acid, 4,6-dioxyphthalic acid, (2,4-dioxyphenyl) acetic acid, (2,6-dioxyphenyl) acetic acid, (3,4,5-trioxyphenyl) ) Acetic acid and the like, but not limited thereto.

  Examples of thiol group-containing aromatic compounds include 5- (4-methoxyphenyl) -1,3,4-oxadiazol-2-thiol, 5-methoxy-2-benzimidazolethiol, and 5-nitro-2-benzimidazole. There are thiols and the like, but not limited thereto.

  The content of the active hydrogen group-containing aromatic compound is the ratio of the sum of the weight of the active hydrogen group-containing aromatic compound and the metal chelate compound to the weight of the polyurethane resin in the relationship of the weight ratio between the polyurethane resin and the metal chelate compound described below. It is important that (polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) is 1.5 to 3.0. Moreover, it is preferable that content of an active hydrogen group containing aromatic compound is 5 to 30% with respect to the heat insulation layer weight, and it is more preferable that it is 10 to 25%. When the active hydrogen group-containing aromatic compound is 5% by weight or more, good adhesion to the substrate or the heat-sensitive layer is obtained, and the resistance to the solvent is high. Furthermore, the crosslinking reaction with the metal chelate compound described later proceeds sufficiently, and the polyurethane resin as the binder polymer is not extracted into the heat-sensitive layer solution when the heat-sensitive layer solution is applied. can get. On the other hand, if the active hydrogen group-containing aromatic compound is 30% by weight or less, the active hydrogen group-containing aromatic compound does not remain unreacted and is extracted into the heat-sensitive layer solution when the heat-sensitive layer solution is applied. The image reproducibility, which is the performance of the printing plate, is not adversely affected.

  In the present invention, the heat insulating layer contains a metal chelate compound. By containing a metal chelate compound, it has good adhesion to the substrate or the heat-sensitive layer, is stable over time, and further has high resistance to a developer or a solvent used during printing.

  Examples of the metal chelate compound referred to in the present invention include an organic complex salt in which an organic ligand is coordinated to a metal, an organic inorganic complex salt in which an organic ligand and an inorganic ligand are coordinated to a metal, and a metal and an organic molecule. Mention may be made of metal alkoxides covalently bonded through oxygen.

  As the main metal forming the organic complex salt, Al, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ge, In, Sn, Zr, and Hf are preferable. Al and Zr are preferable from the viewpoint of low colorability, and Al is more preferable from the viewpoint of reactivity.

  Examples of the ligand include compounds having the following coordination groups having O (oxygen atom), N (nitrogen atom), S (sulfur atom) and the like as donor atoms.

Specific examples of the coordinating group include those having an oxygen atom as a donor atom, -OH (alcohol, enol and phenol), -COOH (carboxylic acid),> C = O (aldehyde, ketone, quinone),- O- (ether), - COOR (ester), - N = O (nitroso compounds, N- nitroso compounds), - NO ₂ (nitro compound),> NO (N- oxide), - _SO 3 H (sulfonic Acids), —PO ₃ H ₂ (phosphorous acid) and the like having nitrogen atoms as donor atoms include —NH ₂ (primary amine, amide, hydrazine),> NH (secondary amine, hydrazine),> N-(3 amine), - N = N- (azo compounds, heterocyclic compounds), = N-OH (oxime), - NO ₂ (nitro compound), - N = O (nitroso compounds),> C = N- (Schiff base, For example, -SH (thiol), -S- (thioether),> C = S (thioketone, thioaldehyde), = S- (heterocyclic compound), -C (= O) -SH or -C (= S) -OH and -C (= S) -SH (thiocarboxylic acid), -SCN (thiocyanate, isothiocyanate), etc. Can be mentioned.

  A ligand containing two or more of these coordinating groups and forming one or more cyclic structures with a metal, specifically β-diketones, ketoesters, diesters, hydroxycarboxylic acids Examples thereof include, but are not limited to, esters and salts thereof, keto alcohols, amino alcohols, and enolic active hydrogen compounds.

Specific examples of such a ligand include the following.
(1) β-diketones: 2,4-pentanedione, 2,4-heptanedione, trifluoroacetylacetone, hexafluoroacetylacetone, dibenzoylmethane, benzoylacetone, benzoyltrifluoroacetone, and the like.
(2) Ketoesters: methyl acetoacetate, ethyl acetoacetate, butyl acetoacetate, octyl acetoacetate and the like.
(3) Diesters: malonic acid dimethyl ester, malonic acid diethyl ester, and the like.
(4) Hydroxycarboxylic acid or esters and salts thereof: lactic acid, methyl lactate, ethyl lactate, ammonium lactate, salicylic acid, methyl salicylate, ethyl salicylate, phenyl salicylate, malic acid, methyl malate, ethyl malate, tartaric acid, methyl tartrate , Ethyl tartrate, etc.
(5) Keto alcohols: 4-hydroxy-4-methyl-2-pentanone, 4-hydroxy-2-pentanone, 4-hydroxy-2-heptanone, 4-hydroxy-4-methyl-2-heptanone and the like.
(6) Amino alcohols: monoethanolamine, diethanolamine, triethanolamine, N-methyl-monoethanolamine, N-ethyl-monoethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine and the like.
(7) Enolic active hydrogen compounds: methylol melamine, methylol urea, methylol acrylamide and the like.

  The metal chelate compound used in the present invention can have the above-described ligand, and among them, an aluminum chelate compound in which one or more ligands selected from alcohols, enols, diesters, and ketoesters are coordinated. Is preferred. Since these aluminum chelate compounds easily cause an exchange reaction with the active hydrogen-containing compound, the aluminum chelate compound itself can be prevented from sublimating or evaporating during heating.

  Moreover, it is particularly preferable to use an aluminum chelate compound in which two or more ketoesters are coordinated. By using such an aluminum chelate compound, it becomes difficult to be affected by moisture, and the storage stability of the heat insulating layer solution is dramatically improved.

  Examples of organic inorganic complex salts include titanium lactate, bisacetylacetonate chloroplatinate, bis (acetylacetonato) diaqua calcium, bis (acetylacetonato) diaquachrome salt, bis (acetylacetonato) diaquacobalt, bis (Acetylacetonato) diaquastrontium, bis (acetylacetonato) diaquanickel, bis (acetylacetonato) diaquabarium, bis (acetylacetonato) diaquamanganese, bis (acetylacetonato) dioxouranium, bis (acetyl) Acetonato) dioxomolybdenum, bisacetylacetonato) dichlorogermanium, bis (acetylacetonato) dichlorogermanium, bis (acetylacetonato) dichlorozirconium, bis (a Chill acetonate) dichlorotitanium, bis (acetylacetonato) dichloro platinum salt, bis (acetylacetonato) dichloro hafnium, bis (there are acetylacetonato) dinitro cobalt salts such as, but not limited thereto.

  Examples of the metal alkoxide include zirconium-n-propoxide, zirconium butoxide, magnesium methoxide, magnesium ethoxide, potassium methoxide, potassium butoxide, sodium methoxide, sodium ethoxide, potassium methoxide, potassium butoxide. There is a side, but it is not limited to these.

  The content of the metal chelate compound is the sum of the weights of the active hydrogen group-containing aromatic compound and the metal chelate compound relative to the weight of the polyurethane resin in the relationship of the weight ratio between the active hydrogen group-containing aromatic compound and the metal chelate compound described later. It is important that the ratio (polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) is 1.5 to 3.0. Furthermore, it is preferable that content of a metal chelate compound is 1 to 30% with respect to the heat insulation layer weight, and it is more preferable that it is 2 to 20%. When the metal chelate compound is 1% by weight or more, good adhesion to the substrate or the heat-sensitive layer is obtained, and the resistance to the solvent is high. Furthermore, the crosslinking reaction with the active hydrogen group-containing aromatic compound described later sufficiently proceeds, and the polyurethane resin as the binder polymer is not extracted into the heat-sensitive layer solution when the heat-sensitive layer solution is applied. Image reproducibility is obtained. On the other hand, if the metal chelate compound is 30% by weight or less, the metal chelate compound remains unreacted and is extracted into the heat-sensitive layer solution when the heat-sensitive layer solution is applied, which adversely affects the performance of the printing plate. There is no.

  Furthermore, in order to improve the softening of the heat insulating layer, natural rubber or synthetic rubber may be contained in the heat insulating layer. These may be used as a softening agent by mixing with polyurethane.

  The heat insulating layer in the present invention preferably contains a pigment. By including the pigment, the light transmittance of the heat insulating layer can be 15% or less with respect to all wavelengths of 400 to 650 nm, thereby improving the plate inspection property by machine reading. Examples of pigments include inorganic white pigments such as titanium oxide, zinc white, and lithopone, inorganic yellow pigments such as yellow lead, cadmium yellow, yellow iron oxide, ocher, and titanium yellow. Organic yellow pigments include acetoacetic allyl monoazo pigments. Azo pigments such as acetoacetic allyl disazo pigments, condensed azo pigments, benzimidazolone monoazo pigments, isoindolinone pigments, isoindoline pigments, selenium pigments, perinone pigments, metal complex pigments, anthrapyrimidine pigments Polycyclic pigments such as acylamino yellow pigments, quinophthalone pigments, and flavantron pigments are preferably used. Among these pigments, titanium oxide is particularly preferable in terms of hiding power and coloring power.

  Titanium oxide particles include anatase type, rutile type, and brookite type, but the rutile type and anatase type are preferred from the standpoint of stability. Further, a titanium oxide surface treated with aluminum, silicon, titanium, zinc, zirconium or the like may be used.

  As for the particle diameter of the titanium oxide particles, the primary particle diameter is preferably 0.2 to 0.3 μm. If the primary particle size is 0.2 μm or more, the concealment performance intended by the present invention can be obtained, and if it is 0.3 μm or less, it is difficult to spontaneously settle, and a heat insulating layer solution with stable dispersion can be obtained. A good coating film can be obtained.

  In the present invention, the surface of the titanium oxide particles may be treated with a titanate coupling agent. By treating the surface of the titanium oxide particles with a titanate coupling agent, the dispersibility of the titanium oxide particles can be improved and a large amount of titanium oxide particles can be contained. Furthermore, the dispersion stability of the coating liquid containing titanium oxide particles is improved.

The content of titanium oxide is preferably 2% by volume or more and 30% by volume or less in the heat insulating layer. If it is 2% by volume or more, good concealment performance is obtained, and if it is 30% by volume or less, good coating performance is exhibited, and scratch resistance, printing durability, and image reproducibility are not adversely affected.
In the present invention, the heat insulating layer contains an alkyl ether (for example, ethyl cellulose, methyl cellulose, etc.), a fluorine-based surfactant, a silicone-based surfactant, or a nonionic surfactant for the purpose of improving coatability. You can also.

  The components constituting the heat insulation layer are preferably dissolved using a solvent. It is preferable that the solvent used for the heat insulating layer composition liquid has a property of sufficiently dissolving an active hydrogen group-containing aromatic compound, a metal chelate compound, a polyurethane resin, and other additives. A solvent can also be used independently and can also be used in mixture of 2 or more types. In addition, when adding a pigment, it is preferable to select a solvent that wets the pigment surface well and provides good pigment dispersibility.

  As a method for preparing the heat insulation layer solution, for example, a titanium oxide dispersion is put into a container, stirring is started, and a resin, a metal chelate compound, and other additives are sequentially added thereto to obtain a high concentration heat insulation layer solution. After that, the insulating layer solution can be obtained by further diluting with a solvent to an arbitrary concentration.

  The titanium oxide dispersion can be obtained, for example, by adding titanium oxide in a solvent and dispersing with a paint shaker, a ball mill or the like.

The thickness of the heat insulating layer in the present invention is preferably 1 to 30 g / ^{m 2,} more preferably from 10 to 20 g / ^{m 2.} If it is 1 g / m ² or more, concealability and good scratch resistance can be obtained, and if it is 30 g / m ² or less, it is economically advantageous.

  In this invention, it is preferable that the light transmittance of a heat insulation layer is 15% or less in all the wavelengths of 400-650 nm, It is more preferable that it is 10% or less, More preferably, it is 5% or less.

  The light transmittance of the heat insulation layer can be measured using, for example, a visible spectrophotometer. If the substrate is transparent, measurement can be performed by the transmission method, and if the substrate is opaque, measurement can be performed by the reflection method. As such a visible spectrophotometer, U-3210 self-recording spectrophotometer manufactured by Hitachi, Ltd. may be mentioned.

  In the present invention, the initial elastic modulus of the heat insulating layer is preferably 5 to 500 MPa, more preferably 5 to 300 MPa. If the initial elastic modulus is 500 MPa or less, sufficient scratch resistance can be obtained, and problems in printing durability are unlikely to occur. Further, the breaking elongation is preferably 10% or more, and more preferably 15% or more. If the elongation at break is 10% or more, the heat insulating layer is brittle, so that the problem that the heat insulating layer is damaged during printing and the printing durability is lowered is unlikely to occur. By adjusting the amount of the polyurethane resin, the active hydrogen group-containing aromatic compound, the metal chelate compound and the pigment contained in the heat insulating layer, a preferable initial elastic modulus and elongation at break can be obtained for the present invention. By adjusting the resin content, the initial elastic modulus and elongation at break within the above ranges can be obtained.

  These tensile properties can be measured according to JIS K6301. Specifically, the heat insulating layer solution is uniformly spread on a Teflon (registered trademark) petri dish, and the solvent is volatilized, followed by heat curing at a curing temperature of 200 ° C. and a curing time of 1 hour. Thereafter, the sheet is peeled off from the Teflon petri dish to obtain a sheet having a thickness of about 100 μm. A 5 mm × 40 mm strip sample is cut out from this sheet, and the initial elastic modulus and elongation at break are measured at a tensile rate of 20 cm / min using Tensilon RTM-100 (Orientec Co., Ltd.). The elongation at break is measured at a temperature of 25 ° C. and a humidity of 50%.

  Next, the heat sensitive layer in the direct-drawing waterless planographic printing plate precursor of the present invention will be described. The heat-sensitive layer in the present invention is a layer having a function of converting laser light used for drawing into heat (photothermal conversion). The heat-sensitive layer of the present invention preferably contains at least (a) a photothermal conversion substance, (b) a metal-containing organic compound, (c) an active hydrogen group-containing compound, and (d) a binder polymer.

  From the printing plate precursor of the present invention, a negative direct-drawing waterless lithographic printing plate can be obtained. That is, the adhesive force between the heat-sensitive layer and the silicone rubber layer in the laser beam irradiation portion is reduced, and the silicone rubber layer in the portion irradiated with the laser beam is removed by subsequent development processing. Although the detailed mechanism is not yet elucidated, the crosslinked structure formed by the reaction between (b) a metal-containing organic compound and (c) an active hydrogen group-containing compound during the production of the original plate is probably converted to (a) photothermal conversion by laser irradiation. It is thought that it was partially decomposed by the heat generated by the action of the substance. As a result, it is considered that the solvent resistance at the interface between the silicone rubber layer and the heat-sensitive layer is lowered, and the silicone rubber layer in the laser irradiated portion is removed by the development treatment. The silicone rubber layer alone or both the silicone rubber layer and the heat-sensitive layer may be removed by development, but it is preferable that the heat-sensitive layer remains because ink mileage is improved.

(A) Photothermal conversion material The photothermal conversion material is not particularly limited as long as it absorbs laser light. For example, black pigments such as carbon black, aniline black, cyanine black, phthalocyanine, naphthalocyanine green pigments , Carbon graphite, iron powder, diamine metal complex, dithiol metal complex, phenol thiol metal complex, mercaptophenol metal complex, crystal water-containing inorganic compounds, copper sulfate, chromium sulfide, silicate compounds, titanium oxide, oxidation Examples thereof include metal oxides such as vanadium, manganese oxide, iron oxide, cobalt oxide, and tungsten oxide, hydroxides of these metals, sulfates, and metal powders of bismuth, iron, magnesium, and aluminum.

  Among these, carbon black is preferable from the viewpoints of photothermal conversion, economic efficiency, and handleability.

  In addition to the above substances, dyes that absorb infrared rays or near infrared rays are also preferably used as photothermal conversion materials.

  As these dyes, all dyes having a maximum absorption wavelength in the range of 400 nm to 1200 nm can be used. Preferred dyes are cyanine-based, phthalocyanine-based, phthalocyanine metal complex-based, naphthalocyanine-based dyes for electronics and recording. , Naphthalocyanine metal complex, dithiol metal complex, naphthoquinone, anthraquinone, indophenol, indoaniline, pyrylium, thiopyrylium, squarylium, croconium, diphenylmethane, triphenylmethane, triphenylmethanephthal , Triallylmethane, phenothiazine, phenoxazine, fluoran, thiofluorane, xanthene, indolylphthalide, spiropyran, azaphthalide, chromenopyrazole Leucooramine, rhodamine lactam, quinazoline, diazaxanthene, bislactone, fluorenone, monoazo, ketoneimine, disazo, polymethine, oxazine, nigrosine, bisazo, bisazostilbene, bis Azooxadiazole, bisazofluorenone, bisazohydroxyperinone, azochrome complex, trisazotriphenylamine, thioindigo, perylene, nitroso, 1: 2 type metal complex, intermolecular CT , Quinoline, quinophthalone, fulgide acid dyes, basic dyes, dyes, oil-soluble dyes, triphenylmethane leuco dyes, cationic dyes, azo disperse dyes, benzothiopyran spiropyran, 3,9-dibromoant Antron, Indanthron, Feno Rufutarein, sulfo phthalein, ethyl violet, methyl orange, fluorescein, methyl viologen, methylene blue, and the like gym loss betaine.

  Among these, cyanine dyes, azurenium dyes, squarylium dyes, croconium dyes, azo disperse dyes, bisazostilbenes, which are dyes for electronics and recording and have a maximum absorption wavelength in the range of 700 nm to 900 nm. Dyes, naphthoquinone dyes, anthraquinone dyes, perylene dyes, phthalocyanine dyes, naphthalocyanine metal complex dyes, polymethine dyes, dithiol nickel complex dyes, indoaniline metal complex dyes, intermolecular CT dyes, benzothiopyrans Spiropyran, nigrosine dye and the like are preferably used.

Further, among these dyes, those having a large molar absorbance coefficient are preferably used. Specifically, ε is preferably 1 × 10 ⁴ or more, and more preferably 1 × 10 ⁵ or more. This is because if ε is 1 × 10 ⁴ or more, the effect of improving sensitivity is easily exhibited.

  These photothermal conversion substances alone have an effect of improving the sensitivity, but the sensitivity can be further improved by using two or more kinds in combination. Further, it is possible to cope with two or more kinds of lasers having different transmission wavelengths by using two or more kinds of photothermal conversion substances having different absorption wavelengths.

  The content of these photothermal conversion substances is preferably from 0.1 to 70% by weight, more preferably from 0.5 to 40% by weight, based on the heat-sensitive layer composition. When the content is 0.1% by weight or more, the sensitivity to laser light is improved, and when the content is 70% by weight or less, the printing durability of the printing plate is improved.

(B) Metal-containing organic compound The metal-containing organic compound referred to in the present invention is a complex compound comprising a central metal and an organic substituent, and the organic metal is coordinated to the central metal, or the central metal is organic. An organometallic compound that is covalently bonded to a substituent. Inorganic compounds such as metal oxides are not in that category. These metal-containing organic compounds are characterized by undergoing a substitution reaction with a compound containing an active hydrogen group.

  Examples of the central metal include metals and semiconductor atoms in the second period to the sixth period of the periodic table. Among these, metals and semiconductor atoms in the third period to the fifth period are preferable, and Al, Si, The four-period metals Ti, Mn, Fe, Co, Ni, Cu, Zn, Ge, and the fifth-period metals In and Sn are particularly preferable.

  A metal-containing organic compound is formed between the above-described metal and an organic substituent, and examples of such forms include the following specific examples.

(1) Metal diketenate A hydrogen atom of an enol hydroxyl group of a diketone is substituted with a metal atom, and the central metal is bonded through an oxygen atom. Since the diketone carbonyl can be further coordinated to the metal, it is a relatively stable compound.

  Specifically, the organic substituent is 2,4-pentadionate (acetylacetonate), fluoropentadionate, 2,2,6,6-tetramethyl-3,5-heptanedionate, benzoylacetonate , Metal pentanedionates (metal acetonates) such as thenoyl trifluoroacetonate and 1,3-diphenyl-1,3-propanedionate, methyl acetoacetate, ethyl acetoacetate, methacryloxyethyl acetoacetate and allyl aceto Examples thereof include metal acetoacetates such as acetate and salicylaldehyde complex salts.

(2) Metal alkoxide A compound in which an organic substituent is bonded to a central metal via an oxygen atom. Examples include metal alkoxides whose organic substituents are methoxide, ethoxide, propoxide, butoxide, phenoxide, allyl oxide, methoxyethoxide, aminoethoxide and the like.

(3) Alkyl metal An organic substituent is directly bonded to the central metal, and in this case, the metal is bonded to a carbon atom. Even if the organic substituent is a diketone, it is classified here if the metal is bonded by a carbon atom. Of these, acetylacetone metal is preferably used.

(4) Metal carboxylates Acetate metal salts, lactic acid metal salts, acrylic acid metal salts, methacrylic acid metal salts, stearic acid metal salts and the like can be mentioned.

(5) Others A metal oxide chelate compound such as titanium oxide acetonate, a metal complex such as titanocene phenoxide, and a hetero metal chelate compound having two or more metal atoms in one molecule can be mentioned.

  Specific examples of the metal-containing organic compounds that are preferably used among the metal-containing organic compounds as described above include the following compounds.

  Specific examples of the aluminum chelate compound include aluminum isopropylate, monosec-butoxyaluminum diisopropylate, aluminum sec-butyrate, ethyl acetate aluminum diisopropylate, propyl acetate aluminum diisopropylate, butyl acetate aluminum diisopropylate, heptyl acetate. Aluminum diisopropylate, hexyl acetate aluminum diisopropylate, octyl acetate aluminum diisopropylate, nonyl acetate aluminum diisopropylate, ethyl acetate aluminum diethylate, ethyl acetate aluminum dibutyrate, ethyl acetate aluminum diheptylate, ethyl acetate aluminum dino Elm , Diethyl acetate aluminum isopropylate, aluminum tris (ethyl acetoacetate), aluminum tris (propyl acetoacetate), aluminum tris (butyl acetoacetate), aluminum tris (hexyl acetoacetate), aluminum tris (nonyl acetoacetate), aluminum tris Acetylacetonate, aluminum bisethylacetoacetate monoacetylacetonate, aluminum diacetylacetonate ethylacetoacetate, aluminum monoacetylacetonate bispropylacetoacetate, aluminum monoacetylacetonate bisbutylacetoacetate, aluminum monoacetylacetonate bishexylacetate Acetate, aluminum monoethylene Acetoacetate bispropyl acetoacetonate, aluminum monoethyl acetoacetate bisbutyl acetoacetonate, aluminum monoethyl acetoacetate bishexyl acetoacetonate, aluminum monoethyl acetoacetate bisnonyl acetoacetonate, aluminum dibutoxide monoacetoacetate, aluminum di Propoxide monoacetoacetate, aluminum dibutoxide monoethyl acetoacetate, aluminum oxide acrylate, aluminum oxide octate, aluminum oxide stearate, trisalizarin aluminum, aluminum-s-butoxide bis (ethylacetoacetate), aluminum di-s-butoxide Ethyl acetoacetate, aluminum-9-oct Tadecenyl acetoacetate diisopropoxide, aluminum phenoxide, aluminum acrylate, aluminum methacrylate, etc.

  Specific examples of the titanium chelate compound include isopropyl triisostearoyl titanate, isopropyl tri-n-stearoyl titanate, isopropyl trioctanoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphite) titanate, tetraisopropyl bis (dioctyl) Phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, Bis (dioctyl pyrophosphate) ethylene titanate, Tris (dioctyl pyrophosphate) ethylene titanate Isopropyl dimethacrylisostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri (dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, isopropyl tri (N-aminoethylaminoethyl) titanate, dicumyl phenyloxyacetate titanate, Diisostearoyl ethylene titanate, isopropyl diisostearoyl cumylphenyl titanate, isopropyl distearoyl methacryl titanate, isopropyl diisostearoyl acryl titanate, isopropyl 4-aminobenzenesulfonyldi (dodecylbenzenesulfonyl) titanate, isopropyltrimethacryl titanate, isopropyldi ( 4-aminobenzoyl) iso Thearoyl titanate, isopropyl tri (dioctyl pyrophosphate) titanate, isopropyl triacryl titanate, isopropyl tri (N, N-dimethylethylamino) titanate, isopropyl trianthranyl titanate, isopropyl octyl, butyl pyrophosphate titanate, isopropyl di (butyl, methyl) Pyrophosphate) titanate, tetraisopropyl di (dilauroyl phosphite) titanate, diisopropyloxyacetate titanate, isostearoyl methacryloxyacetate titanate, isostearoyl acryloxyacetate titanate, di (dioctyl phosphate) oxyacetate titanate, 4-aminobenzenesulfonyldodecyl Benzenesulfonyloxyace Tate titanate, dimethacryloxyacetate titanate, dicumyl phenolate oxyacetate titanate, 4-aminobenzoylisostearoyloxyacetate titanate, diacryloxyacetate titanate, di (octyl, butylpyrophosphate) oxyacetate titanate, isostearoyl methacrylethylene titanate , Di (dioctyl phosphate) ethylene titanate, 4-aminobenzenesulfonyldodecylbenzenesulfonylethylene titanate, dimethacrylethylene titanate, 4-aminobenzoylisostearoylethylene titanate, diacrylethylene titanate, dianthranylethylene titanate, di (butyl, methylpyro Phosphate) ethylene titanate, titanium allyl Cetoacetate triisopropoxide, titanium bis (triethanolamine) diisopropoxide, titanium di-n-butoxide (bis-2,4-pentanedionate), titanium diisopropoxide bis (tetramethylheptanedionate), titanium Diisopropoxide bis (ethyl acetoacetate), titanium methacryloxyethyl acetoacetate triisopropoxide, titanium methylphenoxide, titanium oxide bis (pentanedionate), etc.

  Iron (III) acetylacetonate, dibenzoylmethane iron (II), tropolone iron, tristroporono iron (III), hinokitiol iron, tris hinokitioro iron (III), acetoacetate iron (III), iron (III) benzoyl Acetonate, iron (III) trifluoropentanedionate, salicylaldehyde copper (II), copper (II) acetylacetonate, salicylaldehyde imine copper, kojic acid copper, biscojato copper (II), tropolone copper, bistropolono copper ( II), bis (5-oxynaphthoquinone-1,4) copper, bis (1-oxyanthraquinone) nickel, acetoacetate copper, salicylamine copper, o-oxyazobenzene copper, copper (II) benzoyl acetate, copper (II ) Ethyl acetoacetate, copper (II) methacryloxyethyl acetoacetate, copper (II) Toxiethoxy ethoxide, copper (II) 2,4-pentanedionate, copper (II) 2,2,6,6-tetramethyl-3,5-heptanedionate, zinc N, N-dimethylaminoethoxide, Zinc 2,4-pentanedionate, zinc 2,2,6,6-tetramethyl-3,5-heptanedionate and the like are also preferably used in the present invention.

  Others: salicylaldehyde cobalt, o-oxyacetophenone nickel, bis (1-oxyxanthone) nickel, nickel pyromeconate, salicylaldehyde nickel, allyltriethylgermane, allyltrimethylgermane, ammoniumtris (oxalate) germanate, bis [bis (trimethylsilyl) ) Amino] germanium (II), carboxyethyl germanium sesquioxide, cyclopentadienyltrimethylgermane, di-n-butyldiacetoxygermane, di-n-butyldichlorogermane, dimethylaminotrimethylgermane, diphenylgermane, hexaallyldigerma Noxan, hexaethyldigermanoxane, hexamethyldigerman, hydroxygermatrane monohydrate, methacryloxymethyltrimethyl Tilgermane, methacryloxytriethylgermane, tetraallylgermane, tetra-n-butylgermane, tetraisopropoxygermane, tri-n-butylgermane, trimethylchlorogermane, triphenylgermane, vinyltriethylgermane, bis (2,4-pentanedio Nate) dichlorotin, di-n-butylbis (2,4-pentanedionate) tin, calcium 2,4-pentanedionate, cerium (III) 2,4-pentanedionate, cobalt (II) 2,4-pentane Dionate, cobalt (III) 2,4-pentanedionate, europium 2,4-pentanedionate, europium (III) thenoyl trifluoroacetonate, indium 2,4-pentanedionate, manganese (II) 2,4 -Pentandionate Such as manganese (III) 2,4-pentanedionate be used in the present invention.

  Among these specific examples, particularly preferable metal-containing organic compounds used are aluminum, iron (III), titanium acetylacetonate (pentanedionate), hexanedionate, heptanedionate, ethylacetoacetate, propylacetate. Examples include acetate, tetramethylheptanedionate, and benzoylacetonate.

  These metal-containing organic compounds can be used alone or in admixture of two or more. The content is preferably 5 to 300 parts by weight with respect to 100 parts by weight of the active hydrogen group-containing compound. -150 weight part is further more preferable. When the content is 10 to 300 parts by weight, image reproducibility and printing durability are good, and physical properties of the heat-sensitive layer are not deteriorated.

(C) Active hydrogen group-containing compound The heat-sensitive layer of the printing plate precursor according to the invention preferably contains an active hydrogen group-containing compound in order to form a crosslinked structure with the metal-containing organic compound. Examples of the active hydrogen group-containing compound include a hydroxyl group-containing compound, an amino group-containing compound, a carboxyl group-containing compound, a thiol group-containing compound, and the like, but a hydroxyl group-containing compound is preferable.

  Furthermore, as the hydroxyl group-containing compound, either a phenolic hydroxyl group-containing compound or an alcoholic hydroxyl group-containing compound can be used in the present invention.

  Examples of the phenolic hydroxyl group-containing compound include the following compounds. Hydroquinone, catechol, guaiacol, cresol, xylenol, naphthol, dihydroxyanthraquinone, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, bisphenol A, bisphenol S, novolac resin, resole resin, resorcinbenzaldehyde resin, pyrogallol acetone resin, hydroxystyrene Examples of the polymer include copolymers and copolymers, rosin-modified phenol resins, epoxy-modified phenol resins, lignin-modified phenol resins, aniline-modified phenol resins, melamine-modified phenol resins, and bisphenols.

  Examples of the alcoholic hydroxyl group-containing compound include the following compounds. 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, glycerin, diglycerin, trimethylolpropane, 1,2,4-butanetriol, pentaerythritol, dipentaerythritol, sorbitol, sorbitan, polyvinyl alcohol, cellulose and Derivatives, polymers and copolymers of hydroxyethyl (meth) acrylate and the like.

  In addition, epoxy acrylate, epoxy methacrylate, polyvinyl butyral resin, polymers having a hydroxyl group introduced by a known method, and the like can also be used in the present invention.

  As these hydroxyl group-containing compounds, phenolic hydroxyl group-containing compounds are particularly preferably used from the viewpoint of reactivity with metal-containing organic compounds. In particular, novolak resins, resole resins, resorcinbenzaldehyde resins, pyrogallol acetone resins, polymers and copolymers of hydroxystyrene, rosin modified phenol resins, epoxy modified phenol resins, lignin modified phenol resins, aniline modified phenol resins, melamine modified phenol resins More preferred is a phenolic hydroxyl group-containing resin.

  The amino group-containing compound is not particularly limited as long as it is a compound having a primary, secondary or tertiary amino group in the molecule, and the number of amino groups is not particularly limited. Specifically, aniline, 1-aminobenzene-2,5-disulfonic acid or a salt thereof, methanylic acid or a salt thereof, 4,4′-diaminostilbene-2,2′-disulfonic acid or a salt thereof, sulfamine and the like. is there.

  As carboxyl group-containing compounds, monocarboxylic acids such as formic acid and acetic acid, dicarboxylic acids such as oxalic acid and maleic acid, unsaturated carboxylic acids such as acrylic acid and methacrylic acid, carboxyl group-containing acrylic resins, and carboxyl group-containing compounds Examples include, but are not limited to, polyester resins.

  The kind of thiol group-containing compound is not particularly limited, and any compound having one or more thiol groups may be used. Examples of the thiol group-containing compound include alkyl thiols (eg, methyl mercaptan, ethyl mercaptan, etc.), aryl thiols (eg, thiophenol, thionaphthol, benzyl mercaptan, etc.), amino acids or derivatives thereof (eg, cysteine, glutathione). Etc.), peptide compounds (eg, dipeptide compounds containing cysteine residues, tripeptide compounds, tetrapeptide compounds, oligopeptide compounds containing 5 or more amino acid residues), or proteins (eg, metallothionein or cysteine residues on the surface) And the like, but are not limited thereto.

  It is preferable that the weight average molecular weight (polystyrene conversion) by the GPC (gel permeation chromatography) method of the active hydrogen group containing compound used for this invention is 6000 or less, and 2000-5000 are more preferable. When the weight average molecular weight is 6000 or less, good image reproducibility is obtained without adversely affecting the peeling of the silicone rubber layer in the non-image area, and there is no adverse effect on printing durability.

  In the heat-sensitive layer of the present invention, the above active hydrogen group-containing compounds can be used alone or in admixture of two or more. The content is preferably 5 to 99% by weight, more preferably 20 to 90% by weight, based on the heat-sensitive layer composition. If the content is 5% by weight or more, there will be no problem in printing durability and coating property, and if it is 99% by weight or less, the image reproducibility will not be adversely affected. Moreover, it is preferable that the weight ratio with the content of the (d) binder polymer to be described later is an active hydrogen group-containing compound / binder polymer ≦ 2.4. This improves the image reproducibility and printing durability of the printing plate. The ratio is particularly preferably 1 to 2.4. If it is 1 or more, good image reproducibility is obtained, and if it is 2.4 or less, the printing durability is not adversely affected.

(D) Binder polymer The heat-sensitive layer of the printing plate precursor according to the invention preferably contains a binder polymer from the viewpoint of printing durability. The binder polymer is not particularly limited as long as it is soluble in an organic solvent and has a film-forming ability, but preferably has a glass transition temperature (Tg) of 20 ° C. or lower, more preferably a glass transition temperature of 0 ° C. It is as follows.

  Specific examples of the binder polymer that is soluble in an organic solvent, has a film-forming ability, and also has a function of maintaining a shape include vinyl polymers, unvulcanized rubber, polyoxides (polyethers), polyesters, and polyurethane. However, the present invention is not limited to these.

  The content of these binder polymers is preferably 5 to 80% by weight, more preferably 10 to 60% by weight, based on the heat-sensitive layer composition. If it is 5% by weight or more, printing durability, coating property, and sensitivity are good, and if it is 80% by weight or less, image reproducibility is not adversely affected.

  The binder polymer may be used alone, or several kinds of binder polymers may be mixed and used.

  Furthermore, in the present invention, a leveling agent, a surfactant, a dispersant, a plasticizer and the like may be added to the heat sensitive layer as necessary. In addition, it is extremely preferable to add various coupling agents such as a silane coupling agent in order to enhance the adhesion to the heat insulating layer or the silicone rubber layer.

The thickness of the heat-sensitive layer is preferably 0.1 to 10 g / m ² in terms of printing durability of the printing plate and the ability to easily dilute the diluting solvent, and is excellent in productivity, and more preferably 0.5 to 7 g / m ^2. a m ^2.

  The silicone rubber layer used in the present invention may be either an addition reaction type or a condensation reaction type.

  The components constituting the addition reaction type silicone rubber layer preferably include a vinyl group-containing polysiloxane, a SiH group-containing polysiloxane, and a reaction inhibitor and a curing catalyst for the purpose of controlling the curing rate.

  The vinyl group-containing polysiloxane has a structure represented by the following general formula (I) and has a vinyl group at the molecular end and / or main chain.

(In the formula, n represents an integer of 2 or more, R ¹ and R ² represent a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, and 4 carbon atoms. Represents at least one group selected from the group of ˜50 substituted or unsubstituted aryl groups, which may be the same or different.

From the viewpoint of ink repellency of the printing plate, it is preferable that 50% or more of R ¹ and R ² in the above formula are methyl groups. The molecular weight of the vinyl group-containing polysiloxane can be from several thousand to several hundred thousand, but the weight average molecular weight is 10,000 to 100 from the viewpoints of handleability, ink repellency and scratch resistance of the resulting printing plate. It is preferable to use 10,000, more preferably 50,000 to 600,000. It is also possible to use a mixture of two kinds of vinyl group-containing polysiloxanes having different molecular weights.

  The content of the vinyl group-containing polysiloxane is preferably 50 to 99.9% by weight, more preferably 70 to 98% by weight in the silicone rubber layer composition.

  Examples of the SiH group-containing polysiloxane include compounds having SiH groups in the molecular chain or at the ends, such as those represented by the following general formulas (II) to (V).

(In the general formulas (II) to (V), n represents an integer of 2 or more, and m represents an integer of 1 or more).

  The amount of SiH groups in the SiH group-containing polysiloxane is preferably 2 or more, more preferably 3 or more. As content of SiH group containing polysiloxane, it is preferable that it is 0.1-20 weight% in a silicone rubber layer composition, More preferably, it is 1-15 weight%. Speaking of the quantity ratio with the vinyl group-containing polysiloxane, the molar ratio of SiH group / vinyl group of the vinyl group-containing polysiloxane is preferably 1.5 to 30, and more preferably 10 to 20. When this molar ratio is 1.5 or more, good curability is obtained, and when it is 30 or less, the scratch resistance of the printing plate is not adversely affected.

  A reaction inhibitor may be added as a component of the silicone rubber layer. Examples of the reaction inhibitor include nitrogen-containing compounds, phosphorus compounds, unsaturated alcohols, and the like, and acetylene group-containing alcohols are preferably used. A preferable content of the reaction inhibitor is 0.01 to 10% by weight, further 0.1 to 5% by weight in the total silicone rubber layer.

  As the curing catalyst, for example, a group VIII transition metal compound is used, and a platinum compound is preferable. Specific examples include platinum alone, platinum chloride, chloroplatinic acid, olefin coordination platinum, alcohol-modified complexes of platinum, methylvinylpolysiloxane complexes of platinum, and the like. The amount of such a curing catalyst is preferably 0.01 to 20% by weight, more preferably 0.1 to 10% by weight as a solid content in the silicone rubber layer. If it is 0.01-20 weight%, favorable sclerosis | hardenability will be obtained and it will not have a bad influence on the scratch resistance as a printing plate. In terms of the amount of metal such as platinum in the total silicone rubber layer composition, it is preferably 10 to 1000 ppm, more preferably 100 to 500 ppm.

  In addition to the above-mentioned compounds, the silicone rubber layer improves hydroxyl group-containing organopolysiloxane, hydrolyzable functional group-containing silane or siloxane, known fillers such as silica for the purpose of improving rubber strength, and adhesion. For the purpose, a known silane coupling agent, titanate coupling agent, aluminum coupling agent and the like may be contained. As the silane coupling agent, alkoxysilanes, acetoxysilanes, ketoximine silanes and the like are preferable, and those having a vinyl group and ketoximine silanes are particularly preferable.

  The components constituting the condensation reaction type silicone rubber layer include a hydroxyl group-containing polysiloxane, a crosslinking agent (deacetic acid type, deoxime type, dealcohol type, deamine type, deacetone type, deamide type, deamidoxy type, etc. Here, the hydroxyl group-containing polysiloxane has a structure represented by the following general formula (I) and has a hydroxyl group in the molecular terminal and / or main chain.

(In the formula, n represents an integer of 2 or more, R ¹ and R ² represent a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, and 4 carbon atoms. Represents at least one group selected from the group of ˜50 substituted or unsubstituted aryl groups, which may be the same or different.

About R < ¹ >, R < ² >, it is preferable from the surface of the ink repellency of a printing plate that 50% or more of the whole is a methyl group. Further, molecular weights of several thousands to several hundred thousand can be used, but weight average molecular weights of 10,000 to 200,000, and further 3 from the viewpoints of handling properties, ink repellency and scratch resistance of the obtained printing plate, and the like. It is preferable to use one having 10,000 to 150,000. The content of the hydroxyl group-containing polysiloxane is preferably 50 to 99.9% by weight, more preferably 70 to 99% by weight, based on the total silicone rubber layer composition. It is also possible to use a mixture of two hydroxyl group-containing polysiloxanes having different molecular weights.

  Examples of the crosslinking agent include acetoxysilanes, alkoxysilanes, ketoximine silanes, allyloxysilanes, amidosilanes and aminosilanes represented by the following general formula (VI).

(R ³ ) _4-k SiXk (VI)
(In the formula, k represents an integer of 2 to 4, R ³ represents a substituted or unsubstituted alkyl group having 1 or more carbon atoms, an alkenyl group, an aryl group, or a combination thereof. X represents a halogen atom. And a functional group selected from an alkoxy group, an acyloxy group, a ketoximine group, an aminooxy group, an amide group, and an alkenyloxy group.) In the above formula, the number k of hydrolyzable groups is preferably 3 or 4.

  Specific compounds represented by the general formula (VI) include methyltriacetoxysilane, ethyltriacetoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane. , Tetraethoxysilane, tetrapropoxysilane, vinyltrimethoxysilane, vinyltriphenoxysilane, vinyltriethoxysilane, allyltriethoxysilane, vinyltriisopropoxysilane, vinyltrisisopropenoxysilane, vinylmethylbis (methylethylketoximine) Silane, methyltri (methylethylketoximine) silane, vinyltri (methylethylketoximine) silane, tetra (methylethylketoximine) silane, diisopropenoxydimethyl Orchids, bird isopropenoxysilane carboxymethyl silane, but like tetra allyloxy silanes, but it is not limited thereto. Among these, acetoxysilanes and ketoximinesilanes are preferable from the viewpoints of the curing speed of the ink repellent layer, handling properties, and the like. Moreover, you may mix 2 or more types of these crosslinking agents.

  As content of the crosslinking agent represented by general formula (VI), it is preferable that it is 1.5 to 20 weight% in a silicone rubber layer composition, More preferably, it is 3 to 10 weight%. Speaking of the quantitative ratio with the hydroxyl group-containing polysiloxane, the molar ratio of functional group X / hydroxyl group of the hydroxyl group-containing polysiloxane is preferably 1.5 to 10.0. When this molar ratio is 1.5 or more, good curability is obtained, and when it is 10.0 or less, the scratch resistance of the printing plate is not adversely affected.

  Examples of the curing catalyst include organic carboxylic acids such as acetic acid, propionic acid and maleic acid, acids such as toluenesulfonic acid and boric acid, alkalis such as potassium hydroxide, sodium hydroxide and lithium hydroxide, amines, and titanium tetra Examples thereof include metal alkoxides such as propoxide and titanium tetrabutoxide, metal diketenates such as iron acetylacetonate and titanium acetylacetonate dipropoxide, and metal organic acid salts. Among these, it is preferable to add a metal organic acid salt, and particularly, a metal organic acid salt selected from tin, lead, zinc, iron, cobalt, calcium, and manganese is preferable. Specific examples of such compounds include dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, zinc octylate, and iron octylate. The amount of such a curing catalyst is preferably 0.01 to 20% by weight, more preferably 0.1 to 10% by weight in the silicone rubber composition. When the amount of the curing catalyst is 0.01% by weight or more, sufficient curing of the silicone rubber layer is obtained, and when it is 20% by weight or less, the pot life of the silicone rubber layer solution is not adversely affected.

  In addition, the silicone rubber layer includes a known filler such as silica for the purpose of improving rubber strength, a known silane coupling agent, a titanate coupling agent, an aluminum coupling agent for the purpose of improving adhesiveness, and the like. You may contain.

As for the film thickness of the silicone rubber layer used for this invention, 0.5-20 g / m < ² > is preferable in weight conversion, More preferably, it is 1-4 g / m < ² >. If the film thickness is 0.5 g / m ² or more, an effect of improving ink resilience and scratch resistance is obtained, and if it is 20 g / m ² or less, developability and ink mileage are not adversely affected.

  As the substrate used in the direct-drawing waterless planographic printing plate precursor of the present invention, any known metal, film, etc. can be used as long as it is a dimensionally stable plate-like material. As such a dimensionally stable plate-like material, those conventionally used as a substrate for a printing plate are preferably exemplified.

  A method for producing a direct-drawing waterless planographic printing plate precursor in the present invention will be described.

  Using a normal coater such as a reverse roll coater, air knife coater, gravure coater, die coater, Mayer bar coater, or spin coater such as a whaler, a heat insulating layer solution is applied on the substrate and heated at 100 to 300 ° C. for several minutes. After being cured by heating or actinic ray irradiation, the heat sensitive layer solution is applied and dried by heating at 100 to 180 ° C. for several tens of seconds to several minutes. Thereafter, a silicone rubber solution is applied and heat treated at a temperature of 100 to 200 ° C. for several minutes to obtain a silicone rubber layer.

  If necessary, a protective film is laminated or a protective layer is formed. Examples of the protective film include polyester film, polypropylene film, polyvinyl alcohol film, saponified ethylene vinyl acetate copolymer film, polyvinylidene chloride film, and films on which various metals are deposited.

  Next, a plate making method for producing a printing plate from a direct-drawing waterless lithographic printing plate precursor will be described. The plate-making method usually comprises at least (1) an exposure step, (2) a “pretreatment step” for reducing the adhesion between the silicone rubber layer of the laser-irradiated part and the heat-sensitive layer, and (3) a silicone rubber layer of the laser-irradiated part. It consists of a “development process” for peeling. Further, (4) a “post-treatment step” for dyeing the heat-sensitive layer in the image area with a dyeing solution, and (5) a “water-washing step” for completely washing off the treatment solution and the dyeing solution may be added. Each step will be described in detail.

(1) Exposure process The direct drawing type waterless lithographic printing plate precursor is exposed to a desired image with a laser beam after peeling off the protective film or on the protective film.

  As the laser light source used in the exposure process, one having an emission wavelength region in the range of 300 nm to 1500 nm is usually used. Among these, a semiconductor laser or a YAG laser having an emission wavelength region near the near infrared region is used. Preferably used. Specifically, from the viewpoint of handling of the plate material in a bright room, laser beams having wavelengths of 780 nm, 830 nm, and 1064 nm are preferably used for plate making.

  The surface of the heat-sensitive layer becomes high temperature due to the action of the photothermal conversion substance by laser irradiation, and a decomposition product is generated. On the other hand, since the inside of the heat-sensitive layer is heated to a temperature lower than that of the surface of the heat-sensitive layer, decomposition does not occur and curing proceeds.

(2) Pretreatment step The pretreatment step is a step of immersing the plate in a pretreatment liquid maintained at a predetermined temperature for a predetermined time.

  If the laser irradiation energy in the exposure process is large, the silicone rubber layer in the laser irradiation part can be peeled off without going through the pretreatment process and proceeding directly to the development process. However, when the irradiation energy is small, since the thermal layer is less modified, it is difficult to detect ON / OFF of laser irradiation only by the development process, and development is likely to be impossible. Therefore, the plate is treated with a pretreatment liquid in order to amplify the ON / OFF difference of laser irradiation and develop the low-energy laser irradiation portion.

  In the pretreatment step, the plate is preferably immersed in a pretreatment liquid at a temperature of 30 to 60 ° C. for 10 to 100 seconds. When the plate is immersed in a pretreatment solution at a temperature of 30 to 60 ° C. at 10 to 100 ° C., the heat-sensitive layer is sufficiently swollen and dissolved, so that the adhesive force with the silicone rubber layer can be reduced.

  When the plate is immersed in the pretreatment liquid, the pretreatment liquid penetrates into the silicone rubber layer and eventually reaches the heat sensitive layer. In the upper part of the heat-sensitive layer of the irradiated part, a thermal decomposition product is generated or the solubility in the pretreatment liquid is increased, so the upper part of the heat sensitive layer is swollen or partially dissolved by the pretreatment liquid, The adhesive force between the silicone rubber layer and the heat sensitive layer is reduced. When the printing plate surface is rubbed lightly in this state, the silicone rubber layer in the laser irradiation part is peeled off, and the lower heat-sensitive layer is exposed to form an ink deposit layer. On the other hand, since the heat-sensitive layer in the unirradiated part is insoluble or hardly soluble in the pretreatment liquid, the silicone rubber layer is strongly bonded to the heat-sensitive layer and does not peel off even when rubbed strongly. In this way, the unirradiated portion of the silicone rubber layer is not developed, and this portion repels the ink, thereby forming an image of a waterless lithographic printing plate.

  Since the sensitivity of the printing plate is increased by such a mechanism, the selection of the pretreatment liquid is important. When a pretreatment liquid having a high heat-sensitive layer dissolving ability is used, the unirradiated silicone rubber layer is peeled off, and depending on the degree, even the heat-sensitive layer is developed. As a result, the life of the pretreatment liquid is shortened by contaminating the pretreatment liquid and the like. On the other hand, when a pretreatment solution having a low heat-sensitive layer solubility is used, even the silicone rubber layer in the irradiated area cannot be developed, and the sensitivity of the printing plate cannot be increased.

  As such a pretreatment liquid, a solvent formed by adding a polar solvent such as alcohol, ketone, ester, carboxylic acid or amine to water, or a solvent comprising at least one kind such as aliphatic hydrocarbons and aromatic hydrocarbons. A polar solvent is used in which at least one kind of polar solvent is added. Furthermore, it is preferable to use a glycol compound or glycol ether compound represented by the following general formula (VII) as a main component.

(Here, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ⁵ and R ⁶ represent a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, and l is an integer of 1 to 12). .)
Generally, the glycol ether compound has a higher solubility in the heat sensitive layer than the glycol compound. Therefore, by selecting an appropriate compound among them or mixing them, a pretreatment liquid having optimal selective solubility can be obtained with respect to plate materials having different heat-sensitive layer curing conditions. . The effect as the pretreatment liquid takes into account not only the selective solubility of the heat-sensitive layer but also the swelling ability of the silicone rubber layer. When the silicone rubber layer swells, it becomes easy to peel off the silicone rubber layer, and therefore, it becomes easy to develop even with a pretreatment liquid in which the heat-sensitive layer has low solubility. However, if the silicone rubber layer swells too much, it becomes easy to be scratched during development. Therefore, the pretreatment liquid is designed in consideration of both the selective solubility of the heat sensitive layer and the swelling ability of the silicone rubber.

  Examples of the glycol compound include ethylene glycol, propylene glycol, butylene glycol (1,2-butanediol), 2,3-butanediol, polyethylene glycol of 1 = 2 to 12 in the general formula (VII), and polypropylene glycol. It is done. These glycol compounds can be used alone or in combination of two or more. Among these, from the viewpoint of selective solubility, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, and tetrapropylene glycol, where l = 2 to 4 in the general formula (VII), are the former. It is particularly preferably used as a treatment liquid.

Examples of the glycol ether compound include monoalkyl ethers and dialkyl ethers of the above glycol compounds. Examples of the alkyl group for R ⁵ and R ⁶ include methyl group, ethyl group, propyl group, iso-propyl group, butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, 2 -Ethylhexyl group, nonyl group, decanyl group, undecanyl group, dodecanyl group may be mentioned. Preferred glycol ether compounds include diethylene glycol monomethyl ether (methyl carbitol), diethylene glycol monoethyl ether (ethyl carbitol), diethylene glycol monopropyl ether (propyl carbitol), diethylene glycol monobutyl ether (butyl carbitol), diethylene glycol monohexyl. Ether, diethylene glycol mono-2-ethylhexyl ether, diethylene glycol dimethyl ether (diglyme), diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, trie Lenglycol monobutyl ether, triethylene glycol monohexyl ether, triethylene glycol mono-2-ethylhexyl ether, triethylene glycol dimethyl ether (triglyme), triethylene glycol methyl ethyl ether, triethylene glycol diethyl ether, tetraethylene glycol monomethyl ether, tetra Ethylene glycol monoethyl ether, tetraethylene glycol monopropyl ether, tetraethylene glycol monobutyl ether, tetraethylene glycol monohexyl ether, tetraethylene glycol-2-ethylhexyl ether, tetraethylene glycol dimethyl ether (tetraglyme), tetraethylene glycol methyl ethyl ether Tetra Tylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monohexyl ether, dipropylene glycol mono-2-ethylhexyl ether, tripropylene Glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tripropylene glycol monohexyl ether, tripropylene glycol mono-2-ethylhexyl ether, tetrapropylene glycol monomethyl ether, tetrapropylene glycol Monoech Examples include ether, tetrapropylene glycol monopropyl ether, tetrapropylene glycol monobutyl ether, tetrapropylene glycol monohexyl ether, and tetrapropylene glycol mono-2-ethylhexyl ether.

  The content of the glycol compound or glycol ether compound represented by the general formula (VII) in the pretreatment liquid is preferably 50% by weight to 100% by weight, and more preferably 70% by weight to 95% by weight. When the content is 50% by weight to 100% by weight, the selective solubility of the heat-sensitive layer is excellent and the image reproducibility is good.

  Moreover, it is also preferable to make an amine compound coexist in a pretreatment liquid. Although the amine compound is inferior in selective solubility, it may be added as a secondary component in the pretreatment liquid for the purpose of increasing the sensitivity because the heat-sensitive layer has high solubility.

  As amine compounds, glycol amine compounds such as ethylene glycol amine, diethylene glycol amine, triethylene glycol amine, tetraethylene glycol amine, propylene glycol amine, dipropylene glycol amine, tripropylene glycol amine, methylamine, ethylamine, dimethylamine, Diethylamine, trimethylamine, triethylamine, propylamine, butylamine, amylamine, dipropylamine, dibutylamine, diamylamine, tripropylamine, tributylamine, methyldiethylamine, ethylenediamine, trimethylenediamine, tetramethylenediamine, polyethyleneimine, benzylamine, N, N-dimethylbenzylamine, N, N-diethylbenzyl , N, N-dipropylbenzylamine, o-, or m-, or p-methoxy, or methylbenzylamine, N, N-di (methoxybenzyl) amine, β-phenylethylamine, γ-phenylpropylamine, cyclohexyl Amine, aniline, monomethylaniline, dimethylaniline, toluidine, α- or β-naphthylamine, o- or m-, or p-phenylenediamine, aminobenzoic acid, 2- (2-aminoethyl) ethanol, 2-amino- Examples include 2-methyl-1,3-propanediol, 2-amino-1,3-propanediol, and 2-amino-2-hydroxymethyl-1,3-propanediol.

  The content of the amine compound in the pretreatment liquid is preferably 25% by weight or less, and more preferably 15% by weight or less. When it is 25% by weight or less, the image reproducibility is good.

  In the pretreatment liquid, water, alcohols, carboxylic acids, esters, aliphatic hydrocarbons (hexane, heptane, etc.), aliphatic hydrocarbons (toluene, xylene, etc.), halogenated as necessary Hydrocarbons (such as trichlene) may be contained. Further, a surfactant such as sulfate, phosphate, carboxylate or sulfonate may be added to the pretreatment liquid in order to prevent scratches when rubbing the plate surface during development.

(3) Development process By the pretreatment, since the surface of the heat sensitive layer is swollen or partially dissolved in the laser irradiation portion, the silicone rubber layer is easily peeled off selectively. Therefore, development is performed by rubbing the plate surface with water or another solvent. Development with water is most preferable from the viewpoint of drainage. The pretreatment liquid contains a hydrophilic compound as a main component. Accordingly, development with water is preferable because the processing liquid penetrating the printing plate can be washed away with water. Development may also be performed by spraying warm water or water vapor onto the plate surface. In order to improve developability, water added with a pretreatment liquid may be used. Although the temperature of a developing solution may be arbitrary, 10 to 50 degreeC is preferable.

(4) Post-processing step In order to facilitate confirmation of the image area formed by development, a post-processing step of dyeing with a staining solution may be provided. As a dye used in the dyeing solution, a basic dye, an acid dye, a direct dye, a disperse dye, a reactive dye, or the like can be used alone or in admixture of two or more. Of these, water-soluble basic dyes and acid dyes are preferably used.

  Basic dyes include “Crystal Violet”, “Ethyl Violet”, “Victoria Pure Blue”, “Victoria Blue”, “Methyl Violet”, “DIABACIS MAGENTA” (Mitsubishi Chemical Corporation), “AIZEN BASIC CYANINE 6GH” "(Hodogaya Chemical Co., Ltd.)", "PRIMOCYANINE BX CONC." (Sumitomo Chemical Co., Ltd.), "ASTRAZON BLUE G" (FARBENFARRIKEN BAYER), "DIACRYL SUPRA BRILLIANT 2B" (Mitsubishi Chemical Co., Ltd.) ), “AIZEN CATHILON TURQUOISE BLUE LH” (made by Hodogaya Chemical Co., Ltd.), “AIZEN DIAMOND GREEN GH” (made by Hodogaya Chemical Co., Ltd.), “AIZEN MALACHITE GREEN” (made by Hodogaya Chemical Co., Ltd.), etc. Is used.

  Acid dyes include “ACID VIORET 5B” (Hodogaya Chemical Co., Ltd.), “KITON BLUE A” (CIBA), “PATENT BLUE AF” (BASF), “RAKUTO BRILLIANT BLUE FCF” (Santo Chemical) Kogyo Co., Ltd.), “BRILLIANT ACID BLUE R” (GEIGY), “KAYANOL CYANINE 6B” (Nippon Kayaku Co., Ltd.), “SUPRANOL CYANINE G” (FARBENFARRIKEN BAYER), “ORIENT SOLUBLE BLUE OBB” (Orient Chemical Co., Ltd.), “ACID BRILLIANT BLUE 5G” (manufactured by Chugai Kasei Co., Ltd.), “ACID BRILLIANT BLUE FFR” (manufactured by Chugai Kasei Co., Ltd.), “ACID GREEN GBH” (Takaoka Chemical Industry ( "ACID BRILLIANT MILLING GREEN B" (Hodogaya Chemical Co., Ltd.) etc. are used.

  The content of these dyes in the dyeing solution is preferably 0.01% by weight to 10% by weight, and more preferably 0.1% by weight to 5% by weight.

  Water, alcohols, glycols, glycol monoalkyl ethers, glycol dialkyl ethers are used as the solvent for the dyeing solution. These solvents are used alone or in combination of two or more. Glycols, glycol monoalkyl ethers, and glycol dialkyl ethers have an effect as a processing solution. Therefore, even if the ink repellent layer in the laser irradiation area cannot be developed in the development process and is attached, it is developed in the post-processing process. It can also be made.

  In addition, dyeing assistants, organic acids, inorganic acids, antifoaming agents, plasticizers, and surfactants may be optionally added.

  The temperature of the staining solution may be arbitrary, but is preferably 10 ° C to 50 ° C. It is also possible to dye the image area simultaneously with development by adding the above dye to the developer.

(5) Washing process If the pretreatment liquid or the dyeing solution is still infiltrated into the plate surface, the silicone rubber layer in the non-image area may easily peel off over time. You may provide the water-washing process to wash off completely. The temperature of the washing water may be arbitrary, but is preferably 10 ° C to 50 ° C.

  The development method according to the steps described so far may be either manual development or development by an automatic development apparatus. Development by hand can be carried out by wiping the plate surface by impregnating a nonwoven fabric, absorbent cotton, cloth, sponge or the like with these processing solution, developer and dyeing solution in order. In the case of using an automatic developing device, it is preferable that a pre-processing unit, a developing unit, and a post-processing unit are provided in this order. In some cases, a water washing section may be further provided behind the post-processing section. As such an automatic developing machine, “TWL-1160” and “TWL-650” manufactured by Toray Industries, Inc., or Japanese Patent Laid-Open Nos. 4-2265, 5-2272, and 5-6000 are disclosed. And the like.

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

<Measuring method of (d1715 / d1510)>
The heat insulating layer solution was dried on a 0.225 mm aluminum substrate at 190 ° C. for 78 seconds to provide a heat insulating layer having a thickness of 10 g / m ² . The sample to which the heat insulating layer was applied was cut into a size of 10 cm square and immersed in 2 liters of a heat sensitive layer solvent at 35 ° C. for 20 minutes to extract uncured components in the heat insulating layer in the heat sensitive layer solvent. . After immersion, the heat insulation layer application sample was taken out from the heat sensitive layer solution. The heat-sensitive layer solution containing the extract was evaporated with an evaporator to obtain a solution containing 100 ml of the extract.

The obtained solution containing the extract was applied onto a silicone wafer, and a transmission spectrum was measured under the following conditions using an infrared spectrometer (FTS-55A, manufactured by Bio-Rad DIGILAB) using the FT-IR method. did.
Light source: Special ceramics Resolution: 4cm ^-1
Number of integration: 128 times 1715cm absorption band intensity (d1715) the value obtained by dividing the intensity (d1510) of the absorption band of 1510 cm ^-1 of ^-1 (d1715 / d1510) was calculated.

<Measurement method of insolubilization rate>
The heat insulating layer solution was applied onto a 0.225 mm aluminum substrate, dried at 190 ° C. for 78 seconds, provided with a heat insulating layer, cut into a 10 cm square size for insolubilization measurement, and the initial weight (S) was measured. . The heat insulation layer sample was immersed in tetrahydrofuran at 35 ° C. for 20 minutes. After immersion, the weight (T) was measured. The weight (U) of the remaining aluminum plate was measured, and the insolubilization rate (O) was calculated by the following formula (a).
O = (T−U) / (S−U) × 100 (a)
<Measurement method of initial elastic modulus and elongation at break of thermal insulation layer>
The heat insulating layer solution was uniformly spread on a Teflon (registered trademark) petri dish, and the solvent was volatilized, followed by heat curing at a curing temperature of 200 ° C. and a curing time of 1 hour. Thereafter, the sheet was peeled off from the Teflon petri dish to obtain a sheet having a thickness of about 100 μm. A 5 mm × 40 mm strip sample was cut from this sheet, and the initial elastic modulus and fracture were performed at a tensile speed of 20 cm / min using Tensilon RTM-100 (manufactured by Orientec Co., Ltd.) at a temperature of 25 ° C. and a humidity of 50%. The elongation was measured.

<Measurement method of light transmittance of heat insulation layer>
The heat insulation layer solution was applied to a 150 μm thick polyethylene terephthalate film (Lumirror (registered trademark) manufactured by Toray Industries, Inc.), and a heat insulation layer having a desired film thickness was applied at a curing temperature of 200 ° C. and a curing time of 1 minute. About the obtained film, the transmittance | permeability of the light with a wavelength of 400-650 nm was measured using the spectrophotometer U-3210 (made by Hitachi, Ltd.).

<Image reproducibility evaluation method>
A direct-drawing waterless lithographic printing plate precursor is exposed and developed at 2,400 dpi, 1, 2, 3, 4, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 95, respectively. Printing plates having 96, 97, 98, and 99% halftone dots were prepared.

  The obtained printing plate was observed with a magnifying glass, and the reproducibility of each halftone dot was examined. If a dot of 1 to 99% can be reproduced, it can be said that the image has good image reproducibility.

<Measurement method of halftone dot readability>
A direct-drawing waterless lithographic printing plate precursor is exposed and developed at 2,400 dpi, 1, 2, 3, 4, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 95, respectively. Printing plates having 96, 97, 98, and 99% halftone dots were prepared.

  The obtained printing plate was measured for the dot area ratio using a dot area ratio measuring device “ccDot4 type 3” (manufactured by Center Fax). Measurements were made from a direction perpendicular to and parallel to the aluminum stretch of the substrate of the printing plate, and the difference in measurement results due to the difference in direction was compared. If this difference is 1.0% or less, it can be said that the halftone dot readability is good.

<Scratch resistance evaluation method>
The direct-drawing waterless lithographic printing plate precursor was exposed and developed to prepare a printing plate. Using a continuous weight type scratch strength tester HEIDON-18 (manufactured by Shinto Kagaku Co., Ltd.) on the specific exposure part (non-image part) of this printing plate, on a sapphire needle having a diameter of 0.05 mm The printing plate was moved at 30 cm / min while being continuously loaded from no load to 50 g, and scratched. This printing plate was printed, and the minimum load (g) at which scratches were observed on the printed matter after ink was deposited on the scratches was defined as the scratch resistance value. If the scratch resistance is 15 g or more, the printing plate will not be damaged when the printing plate is handled, the plate surface is washed, and the printing is performed, and there is a problem that the ink is deposited on the scratch and the non-image area is stained. It can be said that it has sufficient scratch resistance.

<Method for evaluating printing durability>
The direct-drawing waterless lithographic printing plate precursor was exposed and developed to prepare a printing plate. The obtained printing plate is attached to an offset printing machine (Komori Sprint 4-color machine) and "Dryo Color" (Dainippon Ink Chemical Co., Ltd.) is used to make high-quality paper using black, red, indigo and yellow ink. A printing test was carried out. The number of prints on which the print paper surface was smeared due to the silicone rubber layer in the non-image area being peeled off in a pinhole shape was defined as the printing durability. If printing durability of 100,000 sheets or more is obtained, it can be said that the printing has good printing durability.

<Preparation of titanium oxide dispersion>
In 10 parts by weight of N, N-dimethylformamide, 10 parts by weight of titanium oxide “CR-50” (manufactured by Ishihara Sangyo Co., Ltd.) was added and stirred for 5 minutes. Furthermore, 15 parts by weight of glass beads (No. 08) was added, and the mixture was vigorously stirred for 20 minutes. Thereafter, the glass beads were removed to obtain a titanium oxide dispersion.

<Composition of heat insulation layer solution 1>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 50 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 500 parts by weight (polyurethane: 100 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemicals Co., Ltd.): 12 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (titanium oxide: 40 parts by weight)
(F) N, N-dimethylformamide: 507 parts by weight (g) Methyl ethyl ketone: 406 parts by weight.

<Composition of heat insulation layer solution 2>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 35 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 375 parts by weight (polyurethane: 75 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 8 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (titanium oxide: 40 parts by weight)
(F) N, N-dimethylformamide: 401 parts by weight (g) Methyl ethyl ketone: 318 parts by weight.

<Composition of heat insulation layer solution 3>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 45 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 550 parts by weight (polyurethane: 110 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 13 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 70 parts by weight (titanium oxide: 35 parts by weight)
(F) N, N-dimethylformamide: 477 parts by weight (g) Methyl ethyl ketone: 408 parts by weight.

<Composition of thermal insulation layer solution 4>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 48 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-SZ18D (manufactured by Sanyo Chemical Industries, Ltd., concentration 15%) , N, N-dimethylformamide solution): 700 parts by weight (polyurethane: 105 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 11 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 76 parts by weight (titanium oxide: 38 parts by weight)
(F) N, N-dimethylformamide: 349 parts by weight (g) Methyl ethyl ketone: 406 parts by weight.

<Composition of the heat insulation layer solution 5>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 35 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-SZ18D (manufactured by Sanyo Chemical Industries, Ltd., concentration 15%) N, N-dimethylformamide solution): 533 parts by weight (polyurethane: 80 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 10 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 70 parts by weight (titanium oxide: 35 parts by weight)
(F) N, N-dimethylformamide: 289 parts by weight (g) Methyl ethyl ketone: 322 parts by weight.

<Composition of heat insulation layer solution 6>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 28 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 500 parts by weight (polyurethane: 100 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 6 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (titanium oxide: 40 parts by weight)
(F) N, N-dimethylformamide: 376 parts by weight (g) Methyl ethyl ketone: 350 parts by weight.

<Composition of heat insulation layer solution 7>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 16 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-SZ18D (manufactured by Sanyo Chemical Industries, Ltd., concentration 15%) N, N-dimethylformamide solution): 480 parts by weight (polyurethane: 72 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 4 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 16 parts by weight (titanium oxide: 8 parts by weight)
(F) N, N-dimethylformamide: 151 parts by weight.

<Composition of the heat insulation layer solution 8>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 18 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 285 parts by weight (polyurethane: 57 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 4 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.1 parts by weight (e) Titanium oxide dispersion (concentration 50%): 42 parts by weight (titanium oxide: 21 parts by weight)
(F) N, N-dimethylformamide: 48 parts by weight (g) Methyl ethyl ketone: 270 parts by weight.

<Composition of the heat insulation layer solution 9>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 8 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 750 parts by weight (polyurethane: 150 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 3 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (titanium oxide: 40 parts by weight)
(F) N, N-dimethylformamide: 303 parts by weight (g) Methyl ethyl ketone: 404 parts by weight.

<Composition of the heat insulation layer solution 10>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 45 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 1400 parts by weight (polyurethane: 280 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 14 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.2 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (titanium oxide: 40 parts by weight)
(F) N, N-dimethylformamide: 616 parts by weight (g) Methyl ethyl ketone: 761 parts by weight.

<Composition of the heat insulation layer solution 11>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 30 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 200 parts by weight (polyurethane: 40 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 8 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.1 parts by weight (e) Titanium oxide dispersion (concentration 50%): 72 parts by weight (36 parts by weight of titanium oxide)
(F) Dimethylformamide: 700 parts by weight (g) Methyl ethyl ketone: 200 parts by weight

<Composition of the heat insulation layer solution 12>
(A) Epoxy resin: Epicoat (registered trademark) 1010 (manufactured by Japan Epoxy Resin Co., Ltd.): 6 parts by weight (b) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%) N, N-dimethylformamide / 2-ethoxyethanol solution): 235 parts by weight (polyurethane: 47 parts by weight)
(C) Aluminum tris (ethyl acetoacetate): “Aluminum chelate” ALCH-TR (manufactured by Kawaken Fine Chemical Co., Ltd.): 3 parts by weight (d) Vinyl polymer: Disparon (registered trademark) LC951 (Enomoto Kasei Co., Ltd.) )): 0.1 parts by weight (e) Titanium oxide dispersion (concentration 50%): 80 parts by weight (40 parts by weight of titanium oxide)
(F) Dimethylformamide: 222 parts by weight (g) Methyl ethyl ketone: 193 parts by weight.

<Composition of thermosensitive layer solution 1>
(A) Infrared absorbing dye: “PROJET” 825LDI (manufactured by Avecia Co., Ltd.): 16 parts by weight (b) Titanium di-n-butoxide bis (2,4-pentanedionate): NACEM (registered trademark) titanium (Nippon Chemical Industries) Manufactured by Co., Ltd., titanium concentration of about 8.8%, n-butanol solution): 37.5 parts by weight (c) phenol novolac resin: Sumilite Resin (registered trademark) PR53195 (manufactured by Sumitomo Bakelite Co., Ltd.): 60 weights Part (d) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%, N, N-dimethylformamide / 2-ethoxyethanol solution): 125 parts by weight (polyurethane: 25 parts by weight) )
(E) 3-glycidoxypropyltrimethoxysilane: 15 parts by weight (f) Tetrahydrofuran: 993 parts by weight (g) Ethanol: 64 parts by weight

<Composition of thermosensitive layer solution 2>
(A) Infrared absorbing dye: “PROJET” 825LDI (manufactured by Avecia Co., Ltd.): 10 parts by weight (b) Titanium di-n-butoxide bis (2,4-pentanedionate): NACEM (registered trademark) titanium (Nippon Chemical Industries) (Co), titanium concentration of about 8.8%, n-butanol solution): 22 parts by weight (c) Phenol novolac resin: Sumilite Resin (registered trademark) PR54652 (manufactured by Sumitomo Bakelite Co., Ltd.): 60 parts by weight ( d) Polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%, N, N-dimethylformamide / 2-ethoxyethanol solution): 50 parts by weight (polyurethane: 10 parts by weight)
(E) 3-glycidoxypropyltrimethoxysilane: 15 parts by weight (f) Tetrahydrofuran: 668 parts by weight (g) Ethanol: 40 parts by weight

<Composition of thermosensitive layer solution 3>
(A) Infrared absorbing dye: “YKR-2900” (manufactured by Yamamoto Kasei Co., Ltd.): 10 parts by weight (b) Titanium di-n-butoxide bis (2,4-pentanedionate): Nursem® titanium (Japan) Chemical Industry Co., Ltd., titanium concentration of about 8.8%, n-butanol solution): 22.5 parts by weight (c) Phenol novolac resin: Sumilite Resin (registered trademark) PR54652 (manufactured by Sumitomo Bakelite Co., Ltd.): 60 parts by weight (d) polyurethane: Samprene (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., concentration 20%, N, N-dimethylformamide / 2-ethoxyethanol solution): 50 parts by weight (polyurethane: 10 Parts by weight)
(E) m-xylylenediamine / glycidyl methacrylate / 3-glycidoxypropyltrimethoxysilane = 1/3/1 mol ratio addition reaction product: 15 parts by weight (f) tetrahydrofuran: 800 parts by weight (g) dimethylformamide: 100 Parts by weight.

<Composition of silicone rubber layer solution 1>
(A) α, ω-divinylpolydimethylsiloxane DMS-V52 (weight average molecular weight 155,000, manufactured by GELEST Inc.): 100 parts by weight (b) Both end methyl (methylhydrogensiloxane) (dimethylsiloxane) copolymer , SiH group-containing polysiloxane HMS-151 (Mole% of MeHSiO: 15-18%, manufactured by GELEST Inc.): 4 parts by weight (c) vinyltri (methylethylketoximine) silane: 3 parts by weight (d) platinum catalyst: “ SRX-212 "(Toray Dow Corning Silicone Co., Ltd.): 10 parts by weight (e) Isopar (registered trademark) E (Esso Chemical Co., Ltd.): 1222 parts by weight.

<Composition of silicone rubber layer solution 2>
(A) α, ω-divinylpolydimethylsiloxane DMS-V52 (weight average molecular weight 155,000, manufactured by GELEST Inc.): 100 parts by weight (b) both end methyl (methylhydrogensiloxane) (dimethylsiloxane) copolymer, SiH group-containing polysiloxane HMS-151 (Mole% of MeHSiO: 15-18%, manufactured by GELEST Inc.): 7 parts by weight (c) Vinyltri (methylethylketoximine) silane: 3 parts by weight (d) Platinum catalyst: “SRX- 212 "(manufactured by Toray Dow Corning Silicone): 5 parts by weight (e) Isopar (registered trademark) E (manufactured by Esso Chemical Co., Ltd.): 1035 parts by weight.
Example 1
The heat insulating layer solution 1 was applied on a 0.225 mm thick degreased aluminum substrate (Mitsubishi Aluminum Co., Ltd.) and dried at 200 ° C. for 1 minute to provide a heat insulating layer having a thickness of 10 g / m ² . The heat-sensitive layer solution 1 was applied on the heat insulating layer and dried at 150 ° C. for 80 seconds to provide a heat-sensitive layer having a thickness of 1.5 g / m ² . On this heat-sensitive layer, the silicone rubber solution 1 was applied and dried at 125 ° C. for 80 seconds to provide a silicone rubber layer having a thickness of 2.0 g / m ² to obtain a direct-drawing waterless lithographic printing plate precursor. Further, a 6 μm polypropylene film was laminated on the surface of the silicone rubber layer.

The obtained direct-drawing waterless planographic printing plate precursor is mounted on a plate making machine “TDL-4400” (manufactured by Toray Industries, Inc.), and image exposure is performed using a semiconductor laser (wavelength 830 nm) at an irradiation energy of 150 mJ / cm ^2. Went. After the polypropylene film is peeled off, an automatic processor “TWL-860KII” (manufactured by Toray Industries, Inc.) is used, and after immersion for 30 seconds in a pretreatment liquid “NP-1” (manufactured by Toray Industries, Inc.), water Brush development was performed under washing, and dyeing was performed with a post-treatment solution “PA-FII” (manufactured by Toray Industries, Inc.). By this series of operations, a negative directly drawn waterless lithographic printing plate in which the silicone rubber layer in the laser-irradiated part was peeled off and the exposed heat-sensitive layer surface was dyed was obtained. Further, using a directly imageable waterless planographic printing plate precursor described above, to obtain a directly imageable waterless planographic printing plate of a negative type of immersion time in the pre-treatment solution after the setting was same process in 24 seconds .

When the obtained printing plate was observed by a loupe, the pretreatment liquid 1 to 99% those immersion time 30 seconds, the thing of 24 seconds has been reproduced dots of 1 to 99%, good It had image reproducibility. Moreover, the difference of the halftone dot area ratio measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good.

  This printing plate is attached to an offset printing machine (Komori Sprint 4-color machine), and “Dryo Color” (Dainippon Ink Chemical Co., Ltd.) is used to print on high-quality paper using black, red, indigo and yellow ink. went. Even after printing 20,000 sheets, a good printed matter was obtained in which the non-image area was not stained. Further, as a result of inspecting the printing plate after completion of printing, it was found that there was no damage such as peeling of the silicone rubber layer in the non-image area part into a pinhole shape, and the printing durability was 150,000 sheets.

  When the scratch resistance was evaluated by the method described above for the laser non-irradiated portion (non-image portion) of the printing plate, the ink was attached to the scratch from the position of the load 30 g, and good scratch resistance was obtained. Had.

Further, a heat insulating layer solution 1 was coated on a polyethylene terephthalate film having a thickness of 150 [mu] m (Toray Industries Co., Ltd. Lumirror (registered trademark)), and dried for 1 minute at 200 ° C., a heat insulating layer having a thickness of 10 g / ^{m 2} Provided. About the obtained film, as a result of measuring the transmittance | permeability of the light of wavelength 400-650nm using the spectrophotometer U-3210 (made by Hitachi, Ltd.), the light transmittance is 1.0% or less in all the wavelengths. Met.

  Further, when the initial elastic modulus and elongation at break of the sheet obtained from the heat insulating layer solution 1 were measured by the method described above, the initial elastic modulus was 211 MPa and the elongation at break was 395%. Moreover, it was 1.6 when (d1715 / d1510) of the sheet | seat obtained from the heat insulation layer solution 1 was measured by the method described previously.

(Examples 2 to 5 )
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that a heat insulating layer was provided as shown in Table 2 .

  In the same manner as in Example 1, image exposure and development were performed to obtain a direct-drawing waterless lithographic printing plate. The evaluation results of the obtained printing plate are as shown in Table 2. When the printing plate was observed with a magnifying glass, halftone dots with an immersion time of 30 seconds were reproduced with 1 to 99%, and those with 24 seconds were reproduced with 1 to 99%. Was. In addition, the difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch marks was 0.5% or less, and the halftone dot readability was good. As a result of printing using these printing plates, all of them had a printing durability of 150,000 sheets. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-image area) of the printing plate, as shown in Table 2, the scratch resistance was good.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 1% or less at all wavelengths. Further, the initial elastic modulus and elongation at break of the sheet prepared from the heat insulating layer solution were as shown in Table 1. It was as Table 1 when the measurement of (d1715 / d1510) was performed.

(Comparative Example 1)
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the heat-insulating layer solution 7 was used and the film thickness of the heat-insulating layer was 8 g / m ² .

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed by a loupe, it was 1 to 99% of that of the immersion time of 30 seconds, the ones 24 seconds has decreased 1 to 70 percent and image reproducibility, poor Met. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 1.0% or less, and the halftone dot readability was good. As a result of printing using this printing plate, it had a printing durability of 150,000 sheets. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-image portion) of the printing plate, ink started to deposit on the scratch from a position where the load exceeded 35 g and had good scratch resistance.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 12% or less. Table 1 shows the initial elastic modulus and elongation at break of a sheet prepared from the heat insulating layer solution 7. When (d1715 / d1510) was measured, it was as shown in Table 1.

(Comparative Example 2)
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the heat-insulating layer solution 8 was used and the film thickness of the heat-insulating layer was 8 g / m ² .

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe, those pickles time 30 seconds immersion is was 1 to 99%, and that of 24 seconds have reduced dot reproducibility, satisfactory image reproducibility It was not obtained. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good. As a result of printing using this printing plate, it had a printing durability of 150,000 sheets. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-imaged portion) of the printing plate, ink started to deposit on the scratch from the position of 17 g load and had good scratch resistance.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 1% or less at all wavelengths. Table 1 shows the initial elastic modulus and elongation at break of the sheet produced from the heat insulating layer solution 8. When (d1715 / d1510) was measured, it was as shown in Table 1.

(Comparative Example 3)
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the heat insulating layer solution 9 was used.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe, those pickles time 30 seconds immersion is was 1 to 99%, and that of 24 seconds have reduced dot reproducibility, satisfactory image reproducibility It was not obtained. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good. As a result of printing using this printing plate, it had a printing durability of 150,000 sheets. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-image portion) of the printing plate, ink started to deposit on the scratch from the position where the load was 32 g and had good scratch resistance.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 1% or less at all wavelengths. Table 1 shows the initial elastic modulus and elongation at break of the sheet produced from the heat insulating layer solution 9. When (d1715 / d1510) was measured, it was as shown in Table 1.

(Comparative Example 4)
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the heat insulating layer solution 10 was used.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed by a loupe, immersion time 30 seconds 1-99% is intended, those of 24 seconds has been reproduced dots of 1% to 50%, good image reproducibility is obtained I couldn't. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 1.0%, and the halftone dot readability was good. As a result of printing using this printing plate, it had a printing durability of 150,000 sheets. Result of scratch resistance test to laser non-irradiation part of the printing plate (non-image portion), and adheres ink to the wound from the position of the load 36g Haji meta.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The maximum transmittance was 20%. Table 1 shows the initial elastic modulus and elongation at break of the sheet produced from the heat insulating layer solution 10. When (d1715 / d1510) was measured, it was as shown in Table 1.

(Comparative Example 5)
Example 1 was used except that the heat insulating layer solution 11, the heat sensitive layer solution 2, and the silicone rubber layer solution 2 were used, the film thickness of the heat insulating layer was 5 g / m ² , and the drying time of the heat insulating layer was 2 minutes. A direct-drawing waterless lithographic printing plate precursor was obtained.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe 1 to 99 percent those zuke time 30 seconds immersion, those of 24 seconds has been reproduced dots of 1 to 99%, have good image reproducibility Was. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good. As a result of printing using this printing plate, the printing durability was 50,000 sheets, which was insufficient. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-image portion) of the printing plate, ink started to deposit on the scratch from the position of 10 g load, and the scratch resistance was insufficient.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 1% or less at all wavelengths. Table 1 shows the initial elastic modulus and elongation at break of the sheet produced from the heat insulating layer solution 11. When (d1715 / d1510) was measured, it was as shown in Table 1.

(Comparative Example 6)
Direct-drawing waterless lithographic printing plate in the same manner as in Example 1 except that the heat-insulating layer solution 7, the heat-sensitive layer solution 3, and the silicone rubber layer solution 2 were used, and the film thickness of the heat-insulating layer was 8 g / m ^2. I got the original version.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe 1 to 99 percent those zuke time 30 seconds immersion, those of 24 seconds are reproduced 1 to 80% of the halftone dot image reproducibility is insufficient there were. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 1.0% or less, and the halftone dot readability was good. As a result of printing using this printing plate, the printing durability was 50,000 sheets, which was insufficient. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-imaged portion) of the printing plate, ink started to deposit on the scratch from the position where the load was 35 g and had good scratch resistance.

(Comparative Example 7)
Direct-drawing waterless lithographic printing plate in the same manner as in Example 1 except that the heat insulating layer solution 8, the heat sensitive layer solution 3, and the silicone rubber layer solution 2 were used and the film thickness of the heat insulating layer was 8 g / m ^2. I got the original version.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe 1 to 99 percent that of the immersion time of 30 seconds, the ones 24 seconds have been reproduced dots of 1 to 95%, the image reproducibility is insufficient there were. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good. As a result of printing using this printing plate, the printing durability was 50,000 sheets, which was insufficient. As a result of performing a scratch resistance test on the laser non-irradiated portion (non-image portion) of the printing plate, ink started to deposit on the scratch from the position of the load 17 g and had good scratch resistance.

(Comparative Example 8)
A direct-drawing waterless lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the heat insulating layer solution 12 was used.

Image exposure and development were performed in the same manner as in Example 1 to obtain a direct-drawing waterless lithographic printing plate. When the obtained printing plate was observed with a loupe 1 to 99 percent that of the immersion time of 30 seconds, the ones 24 seconds have been reproduced dots of 1 to 75%, the image reproducibility is insufficient there were. The difference between the halftone dot area ratios measured from the perpendicular direction and the parallel direction with respect to the aluminum stretch was 0.5% or less, and the halftone dot reading property was good. As a result of printing using this printing plate, it had a printing durability of 150,000 sheets. As a result of conducting a scratch resistance test on the laser non-irradiated portion (non-imaged portion) of the printing plate, ink started to deposit on the scratch from the position where the load was 30 g and had good scratch resistance.

Moreover, as a result of measuring the transmittance | permeability of light with a wavelength of 400-650 nm of the heat insulation layer of the film thickness of Table 2 apply | coated on the 150-micrometer-thick polyethylene terephthalate film (Toray Co., Ltd. Lumirror (trademark)), light The transmittance was 1% or less at all wavelengths. Table 1 shows the initial elastic modulus and elongation at break of the sheet prepared from the heat insulating layer solution. When (d1715 / d1510) was measured, it was as shown in Table 1.

Claims (4)

A direct-drawing waterless lithographic printing plate precursor having at least a heat insulating layer, a heat sensitive layer, and a silicone rubber layer in this order on a substrate, wherein the heat insulating layer is at least a polyurethane resin, an active hydrogen group-containing aromatic compound, and a metal chelate compound The content of the polyurethane resin is 40% to 55% with respect to the weight of the heat insulating layer, and the sum of the weights of the active hydrogen group-containing aromatic compound and the metal chelate compound with respect to the weight of the polyurethane resin in the heat insulating layer The ratio (polyurethane resin / (active hydrogen group-containing aromatic compound + metal chelate compound)) of 1.5 to 3.0 is a direct drawing type waterless planographic printing plate precursor. The direct drawing according to claim 1, wherein the transmittance of the heat insulating layer with respect to light having a wavelength of 400 to 650 nm is 15% or less at all wavelengths, and the initial elastic modulus of the heat insulating layer is 5 to 500 MPa. Waterless lithographic printing plate precursor. 3. The direct-drawing waterless lithographic printing plate precursor according to claim 1, wherein the elongation at break of the heat insulating layer is 10% or more. The directly imageable waterless planographic printing plate precursor according to claim 1, wherein the thickness of the heat insulating layer is 1 to 30 g / m ^2.