JPH0882922A - Original plate of waterless planographic printing plate - Google Patents

Abstract

PURPOSE: To enhance sensitivity, to ensure superior image reproducibility over the region from a highlight part to a shadow part and to improve the property to prevent the image from being disturbed by a film edge, dust, etc., at the time of image forming by exposure by using a specified photosensitizer. CONSTITUTION: This original plate has a photosensitive layer contg. a photosensitizer selected from among bis(alkylamino)benzophenone, a thioxanthone deriv. and a compd. having the absorption max. in a wavelength region of >400nm. The bis(alkylthio)benzophenone is represented by formula I (where each of R<1> -R<4> is 1-20C alkyl). The thioxanthone deriv. is represented by formula II (where each of R<5> -R<8> is a functional group such as H or halogen). The compd. having the absorption max. in a wavelength region of >400nm is an acridone deriv. represented by formula III (where each of R<9> -R<13> is a functional group such as H, halogen or 1-20C optionally substd. alkyl).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterless lithographic printing plate, and more particularly to a waterless lithographic printing plate which has high sensitivity and is excellent in plate-making workability such as burn-off property of film edges and dust. It is a thing.

[0002]

2. Description of the Related Art Waterless lithographic printing means that an image area and a non-image area are basically on the same plane, and the image area is ink receptive and the non-image area is ink repellent. In the lithographic printing method, in which the ink is applied only to the image area using the difference in the ink adhesion, and then the ink is transferred to the material to be printed, such as paper, for printing, the non-image area is silicone. It means a printing method comprising a substance having ink repulsion property such as rubber and a fluorine-containing compound and capable of printing without using fountain solution.

By the way, as a waterless planographic printing plate having excellent performance in practical use, one using a silicone rubber layer as an ink repellent layer, for example, as a positive working one, Japanese Patent Publication No. 54- 26923
JP-A-60-21050 and JP-A-60-21050 for negative working, and JP-B-46-16044, JP-A-55-59466 and JP-A-56-8.
Japanese Patent Publication No. 0046, Japanese Patent Publication No. 61-54222 and the like are listed.

These waterless lithographic printing plates are usually exposed to actinic radiation through a positive or negative film. Then, after that, by being developed, only the silicone rubber layer corresponding to the image area is peeled off to expose the photosensitive layer, and the ink image receptive area is formed.

By the way, among the waterless lithographic printing plates described above, many proposals have been made as a photosensitizer used for the photopolymerizable photosensitive layer of a waterless lithographic printing plate for positive working.

In Japanese Patent Publication No. 60-26125,
A system combining bis (dialkylamino) benzophenone as a photosensitizer and thioxanthone as a specific aromatic carbonyl compound has been proposed.

This system is an excellent photosensitizer system having both the sensitivity improving effect of a benzoin sensitizer and the storage stability of a ketone sensitizer. However, such a thioxane derivative alone or a photosensitizer is used. In the combination system of sensitizers, 4
Since the photosensitizer component having the maximum absorption wavelength is not included in the long wavelength region exceeding 00 nm, the sensitivity of the lithographic printing plate having a light emission intensity to the metal halide lamp, which is a general-purpose exposure light source, is insufficient. Met.

Further, JP-A-61-145203 proposes a system in which a nuclear halogen-substituted acridone and bis (dialkylamino) benzophenone are combined as a photosensitizer. Nuclear halogen substituted acridone is 40
It is an excellent photosensitizer with an absorption maximum wavelength in the long wavelength region exceeding 0 nm, and improves the burn-off property of film edges and dust, but the sensitivity improvement effect, especially the sensitivity improvement effect for a single wavelength light source. Was insufficient.

Further, in JP-A-3-274051, trimethylolpropane triacrylate 10 is used.
A proposal was made to add a thioxanthone derivative having a solubility of 5 g or more to 0 ml to the photosensitive layer, and in the examples of the publication, ethyl Michler's ketone (4,4'-bis (diethylamino) benzophenone) and various thioxanthone derivatives were added. A combination is proposed. However, such a thioxane derivative alone or a combination of photosensitizers does not include a photosensitizer component having an absorption maximum wavelength in a long wavelength region of more than 400 nm, and thus emits light in a long wavelength region. It cannot be said that the energy of the light source having a component is efficiently used, and the effect of improving sensitivity to a metal halide lamp, which is a general-purpose exposure light source of a lithographic printing plate having emission intensity in the long wavelength region, and film edge and dust The burn-off property of was insufficient.

Further, JP-A-4-174437, JP-A-4-324865, JP-A-4-338954, JP-A-5-34921, and JP-A-5-349.
24, JP-A-5-53318, and JP-A-5-
In Examples such as 88378, JP-A-5-94009, JP-A-5-100432, JP-A-5-142762, and JP-A-5-281714, ethyl Michler's as a photosensitizer is used. Ketone (4
A system in which 4'-bis (diethylamino) benzophenone) and 2,4-diethylthioxanthone are combined has been proposed. Such a combination also has the same effect of improving the sensitivity and burning of film edges and dust as in the above case. The flyability was insufficient.

As a result of intensive studies made by the present inventors on these conventional problems, a combination of (I) bis (dialkylamino) benzophenone, (II) thioxanthone and its derivatives, which has been proposed hitherto, and 400 n
Simple addition by combining three photosensitizers of (III) acridone and its derivative having a specific structure having an absorption maximum wavelength in a long wavelength region exceeding m, preferably in a specific composition range. It has been found that a dramatic improvement in sensitivity that cannot be explained by the properties is exhibited, and that excellent image reproducibility is exhibited from the highlight part to the shadow part, and the burn-off property of film edges and dust is improved.

[0012]

That is, the present invention provides a waterless lithographic printing plate precursor in which at least a photosensitive layer and an ink repellent layer are provided in this order on a substrate, the photosensitive layer having the following (I) and (II): And a waterless planographic printing plate precursor characterized by containing at least one photosensitizer selected from each of the groups (III).

(I) Bis (alkylamino) benzophenone (II) Thioxanthone derivative (III) A compound having an absorption maximum in a wavelength region exceeding 400 nm.

The ink repellent layer used in the present invention will be described.

Examples of the ink repellent layer include silicone rubber and fluorine-containing compounds (for example, rubber having fluorine in the molecule), but silicone rubber is preferably used because of easy material supply. Such a silicone rubber layer is prepared by diluting a polyorganosiloxane with a silicone gum composition obtained by adding a crosslinking agent and a catalyst, if necessary, to a suitable solvent, coating the same on the photosensitive layer, and heating and drying. It is formed by curing.

As the silicone gum composition which is preferably used in the present invention, a wet heat-curable condensation reaction crosslinkable silicone gum composition and a heat-curable addition reaction crosslinkable silicone gum composition are preferably used.

First, a moisture-heat curable condensation reaction crosslinkable silicone gum composition will be described.

The polyorganosiloxane used herein means a linear polyorganosiloxane represented by the following general formula (1). The silicone gum composition referred to in the present invention means an uncured (non-rubberized) solution composition prepared by dissolving the polyorganosiloxane in an appropriate solvent to form a solution, and then mixing the solution with a crosslinking agent, a catalyst and the like. On the other hand, the silicone rubber means a cured product obtained by subjecting the silicone gum composition to a crosslinking reaction under an appropriate curing condition to form a rubber.

[0019]

Embedded image (Here, n is an integer of 1 or more, R ¹ and R ² are each a carbon number of 1 to 1.
10 alkyl groups, alkoxy groups, aminoalkyl groups,
Haloalkyl group, hydroxyalkyl group, carbon number 2 to 1
A carboxyalkyl group of 0, a cyanoalkyl group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, an aryloxy group, an aralkyl group, or a group selected from a hydrogen atom and a hydroxyl group, which may be the same or different. May be. Further, it has at least one hydroxyl group in the molecular chain in the form of a chain end or a side chain. As the condensation reaction crosslinkable silicone gum composition preferably used in the present invention, a crosslinking agent and, if necessary, a catalyst are added to an organic solvent solution of the linear polyorganosiloxane represented by the general formula (1). In addition, it takes a so-called room temperature (low temperature) moisture curing type. As the cross-linking agent used for constituting the silicone gum composition, acetoxysilane, ketoxime silane, alkoxysilane, aminosilane, amidosilane and the like, which are represented by the following general formula (2), are preferably used, and are usually used. , A cross-linking agent that reacts with a linear polyorganosiloxane having at least one or more hydroxyl groups in the molecular chain and cross-links in a condensation reaction in the form of deacetic acid, deoxime, dealcohol, deamine, deamide, etc. , In single or mixed form or in the form of condensates.

Particularly in the present invention, ketoxime silane, alkoxy silane and the like are preferably used.

Rm · Si · Xn (2) (where m and n are integers satisfying m ≧ 0 and n ≧ 1 and m + n = 4. R is a substituted or unsubstituted C 1 to C 20 Alkyl group, aminoalkyl group, aminoalkyleneaminoalkyl group, aminoalkyleneaminomethylphenethyl group, substituted or unsubstituted carbon number 6 to 2
0 represents an aryl group, and X represents —OR ¹ , —OCOR ² ,
^{-O-N = CR 3 -R 4} , a -O-C = CR ⁵ H. R ^{1 to} R ⁵ mean a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms) Specific examples of the crosslinking agent alone or its condensate are as follows.

Tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, tetraacetoxysilane, methyltriacetoxysilane, Ethyltriacetoxysilane, dimethyldiacetoxysilane, γ-aminopropyltriethoxysilane, N- (βaminoethyl) -γ-aminopropyltrimethoxysilane, N- (βaminoethyl) -γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-chloropropyltriethoxysilane, N- (βaminoethyl) aminomethylphenethyltrimethoxysilane, - (beta-aminoethyl) aminomethyl phenethyl triethoxysilane, tris (methyl ethyl ketoxime) methylsilane, tris (methyl ethyl ketoxime) ethylsilane, tris (methyl ethyl ketoxime) vinylsilane, tetrakis (methyl ethyl ketoxime) silane.

Organotin compounds such as dibutyltin diacetate, dibutyltin dilaurate and dibutyltin dioctoate are preferably used as the catalyst.

The general form of the condensation reaction-crosslinkable silicone gum composition preferably used in the present invention is as follows.

(1) Polyorganosiloxane represented by the general formula (1) 100 parts by weight (2) Condensation reaction cross-linking agent represented by the general formula (2) 3 to 20 parts by weight (3) Condensation catalyst 0.01 ~ 20 parts by weight (4) Solvent 100-4000 parts by weight

Next, a thermosetting addition reaction-crosslinking silicone gum composition will be described.

As used herein, polyorganosiloxane refers to polyvalent hydrogen polyorganosiloxanes and polyorganosiloxanes having two or more --CH.dbd.CH-- groups in the molecule, which are suitable solvents. After being melted to form a mixed solution, a catalyst, a curing retarder and the like are added if necessary to obtain an uncured (unrubbed) silicone gum composition.

The following is a general form of the addition reaction-crosslinkable silicone gum composition that is preferably used in the present invention.

(1) 100 parts by weight of polyorganosiloxane having at least two alkenyl groups (preferably vinyl groups) directly bonded to a silicon atom in one molecule (2) at least two —SiH groups in one molecule Hydrogen polyorganosiloxane having the above 0.1 to 1000 parts by weight (3) Addition catalyst 0.00001 to 20 parts by weight (4) Solvent 100 to 4000 parts by weight

The alkenyl group of the polyorganosiloxane represented by the component (1) may be at the terminal or in the middle of the molecular chain, and the organic group other than the alkenyl group may be a substituted or unsubstituted alkyl group or aryl group. You can choose. Moreover, you may have a trace amount of hydroxyl groups as needed. The polyorganosiloxane shown in component (2) is a component
Although it reacts with (1) to form a silicone rubber layer, it also plays the role of imparting adhesiveness to the photosensitive layer. component
The hydrogen group of (2) may be at the terminal or in the middle of the molecular chain, and the organic group other than hydrogen can be selected from the same functional groups as the component (1).

From the viewpoint of ink repellency, it is preferable that the organic groups of the components (1) and (2) are methyl groups in 60% or more of the total number of functional groups. The molecular structures of the components (1) and (2) may be linear, cyclic or branched, and it is preferable that at least one of them has a number average molecular weight of more than 1000 from the viewpoint of rubber physical properties, and more preferably Ingredient (1)
It is preferable that the polyorganosiloxane (1) has a number average molecular weight of 1,000 or more.

Specific examples of the polyorganosiloxane of the component (1) include α, ω-divinylpolydimethylsiloxane and (methylvinylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both ends.

Specific examples of the polyorganosiloxane as the component (2) include polydimethylsiloxane having hydrogen groups at both ends,
Examples include α, ω-dimethyl polymethyl hydrogen siloxane, (methyl hydrogen siloxane) (dimethyl siloxane) copolymers having methyl groups at both ends, and polymethyl hydrogen cyclics.

The addition catalyst of the component (3) can be freely selected from known ones, but a platinum compound is particularly preferably used. Specific examples include platinum simple substance, platinum chloride, chloroplatinic acid, and olefin-coordinated platinum chain. Further, a curing retarder or the like is added for the purpose of appropriately suppressing the curing rate of these addition reaction-crosslinkable silicone gum compositions.
Specific examples thereof include vinyl group-containing organopolysiloxanes such as tetracyclo (methylvinyl) siloxane, carbon-carbon triple bond-containing alcohols such as acetylacetone alcohol, acetone, methyl ethyl ketone, methanol, ethanol and propylene glycol monomethyl ether.

These addition reaction-crosslinkable silicone gum compositions include hydroxyl group-containing polyorganosiloxanes and hydrolyzable functional groups defined in known silane coupling agents and condensation reaction-crosslinkable silicone gum compositions. It is also possible to add a small amount of a condensation reaction cross-linking agent containing.

These silicone gum compositions which are preferably used in the ink repellent layer of the present invention include known fillers and fillers for the purpose of appropriately reinforcing the ink repellent layer formed by the silicone gum composition. It is also possible to add inorganic particles, silicic acid sol, or the like, or to add a small amount of a known modified silicone oil having no crosslinkable functional group.

As a solvent for diluting and dissolving these silicone gum compositions, paraffinic hydrocarbons, isoparaffinic hydrocarbons, cycloparaffinic hydrocarbons and aromatic hydrocarbons are used alone or in a mixed form. Typical of these hydrocarbon solvents are:
Examples include fractionated petroleum products and modified products thereof.

The thickness of the silicone rubber layer preferably used as the ink repellent layer of the present invention is 0.5 in terms of dry weight from the viewpoint of maintaining printing durability and ink repellent property and maintaining good image reproducibility. It ranges preferably to 10 g / m ^2, more preferably in the range of 1 to 3 g / m ^2.

Next, the photosensitive layer used in the present invention will be described.

As the photosensitive layer of the present invention, a photopolymerizable photosensitive layer in which a monomer or an oligomer initiates radical polymerization by photoexcitation of a photosensitizer is used.

The monomer used in the present invention will be described. The monomer preferably used in the present invention includes a monomer represented by the following general formula (3).

R ¹ R ² N- (X ¹ ) _p- (X ² ) _q -NR ³ R ⁴ (3) (wherein X ¹ is a substituted or unsubstituted cyclic or non-substituted ^one having 1 to 20 carbon atoms). Represents a divalent linking group selected from a cyclic alkylene, a substituted or unsubstituted phenylene, a substituted or unsubstituted aralkylene, a substituent having an alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, an aryl group; X ² is -OE ^1- , -SE ^2- , -NH-E ^3- , -C.
It represents a divalent linking group selected from OOE ⁴ -and -SO2-NH-E ^5- . E ¹ , E ² , E ³ , E ⁴ , E ⁵ are the above X ¹
Represents the same group as. p is an integer of 1 or more, q is 0 or 1
Represents the above integers. R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms,
A substituted or unsubstituted phenyl group, a substituted or unsubstituted aralkyl group, or a functional group selected from the following formulas (4), (5), and (6), and may be the same or different. Examples of the substituent include an alkyl group having 1 to 6 carbon atoms, a halogen atom, a hydroxyl group, and an aryl group. However, 1 of compound (3)
At least one ethylenically unsaturated group is contained in the molecule. R ⁵ , R ⁶ and R ⁷ are each a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted aralkyl group, CH ₂ = CH-
Represents a group, CH ₂ ═CCH ₃ — group. Y represents -CO-O-, -CO-NH-, or a substituted or unsubstituted phenylene group.
X ³ , X ⁴ and X ⁵ mean the same groups as those of X ¹ or X ² . m and n represent 0 or 1. )

Embedded image In particular, those obtained by subjecting the following diamine compound to an addition reaction with a glycidyl (meth) acrylate having a photopolymerizable group and a monoglycidyl ether compound having no photopolymerizable group are preferably used.

(1) Diamine compound (monooxyethylene diamine, dioxyethylene diamine, trioxyethylene diamine, tetraoxyethylene diamine, pentaoxyethylene diamine, hexaoxyethylene diamine, heptaoxyethylene diamine, octaoxyethylene diamine, nonaoxyethylene diamine, decaoxyethylene diamine, trioxyethylene diamine Triacontaoxyethylenediamine, monooxypropylenediamine, dioxypropylenediamine, trioxypropylenediamine,
Tetraoxypropylenediamine, pentaoxypropylenediamine, hexaoxypropylenediamine, heptaoxypropylenediamine, octaoxypropylenediamine, nonaoxypropylenediamine, decaoxypropylenediamine, tritriacontaoxypropylenediamine, N-hydroxyethylhexapropylenediamine, N-hydroxyisopropylhexapropylenediamine, N, N'-dihydroxyethylhexapropylenediamine, N, N'-dihydroxyisopropylhexapropylenediamine, trimethylenebis (4-aminobenzoate), (tetramethyleneglycolbis (4-aminobenzoate ), Dibutylene glycol bis (4-aminobenzoate), o-xylylenediamine, m-xylylenediene Amine, p-xylylenediamine, N-hydroxyethyl-m-xylylenediamine,
N-hydroxyisopropyl-m-xylylenediamine, N, N'-dihydroxyethyl-m-xylylenediamine, N, N'-dihydroxyisopropyl-m-xylylenediamine, etc.) 1 mol (2) glycidyl (meth) acrylate
4-n mol (3) monoglycidyl ether compound (methyl glycidyl ether, ethyl glycidyl ether, n-propyl glycidyl ether, isopropyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, n-hexyl glycidyl ether, 2 ethylhexyl Glycidyl ether, n-decyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, glycidol, etc.)
The addition reaction product of nmol (n is an integer of 0 ≦ n ≦ 4) is useful.

For the purpose of controlling the adhesive force between the photosensitive layer and the ink repellent layer, an ethylenically unsaturated compound having an organic silyl group as shown below is also preferably added to the photosensitive layer.

As the ethylenically unsaturated group compound having an organic silyl group which is preferably added to the present invention, a photopolymerizable ethylenically unsaturated compound is preferably used.

The organic silyl group referred to in the present invention can be roughly classified into two groups, a hydrolyzable active silyl group and a non-hydrolyzable silyl group.

The first hydrolyzable active silyl group is a silyl group such as an alkoxysilyl group, an acetoxysilyl group or an oximesilyl group, which is regenerated by a highly reactive group such as a silanol group by hydrolysis, and a trimethylsiloxy group, Examples thereof include those in which alcoholic hydroxyl groups are regenerated by hydrolysis such as triethylsiloxy group and triphenylsiloxy group.

Specific examples of the alkoxysilyl group include trimethoxysilyl group, triethoxysilyl group, methyldimethoxysilyl group, methyldiethoxysilyl group, vinyldimethoxysilyl group, vinyldiethoxysilyl group, allyldimethoxysilyl group and allyl. Diethoxysilyl group, 3-
Methacryloxypropyl dimethoxysilyl group, 3-methacryloxypropyl diethoxysilyl group, dimethylmethoxysilyl group, dimethylethoxysilyl group, divinylmethoxysilyl group, divinylethoxysilyl group, diallylmethoxysilyl group, diallylethoxysilyl group, 3-methacryl Roxypropylmethylmethoxysilyl group, 3-methacryloxypropylmethylethoxysilyl group, etc.

Specific examples of the acetoxysilyl group include triacetoxysilyl group, methyldiacetoxysilyl group,
Ethyldiacetoxysilyl group, dimethyldiacetoxysilyl group, diethylacetoxysilyl group, etc.

Specific examples of the oxime silyl group include tris (methylethylketoxime) silyl group, methyldi (methylethylketoxime) silyl group, ethyldi (methylethylketoxime) silyl group, vinyldi (methylethylketoxime) silyl group and the like.

As the ethylenically unsaturated group compound having a hydrolyzable active silyl group, the above active silyl group and the photopolymerizable or photocrosslinkable ethylenically unsaturated group may be present in the same molecule. For example, although the molecular structure is not limited, the following compounds are common because of their ease of synthesis and availability.

That is, as the photopolymerizable one, a (meth) acrylic acid ester or an allyl ester derived from a polyhydric alcohol having 30 or less carbon atoms, a polyhydric acid, an acid anhydride or a polyvalent amine, (meth) Acrylamide, an ethylenically unsaturated group compound such as an epoxy ester adduct, etc. may be reacted with a compound having an organic silyl group defined above in the same molecule during or after the step of synthesizing these compounds. The method of incorporating an organic silyl group is common.

Examples of the above-mentioned organic silyl group compound used in the reaction include a chloroalkylsilyl compound, an epoxyalkylsilyl compound, an aminoalkylsilyl compound, a mercaptoalkylsilyl compound, and an isocyanatopropylsilyl compound. Group, amino group, mercapto group, isocyanate group, etc. are used for the reaction. Further, it is also possible to react a part of the polyvalent acetoxysilyl group or the polyvalent oxime silyl group (for example, by reacting a trioxime silyl group to form a dioxime silyl group) to incorporate an organic silyl group.

Specific examples are shown below, but the present invention is not limited thereto.

Example 1 2-Hydroxypropyl (meth) acrylate 1 mol Vinyltris (methylethylketoxime) silane 1 mol Example 2 Pentaerythritol triacrylate 1 mol Trimethoxychlorosilane 1 mol Example 3 Ethylene glycol diglycidyl ether / methacrylic acid adduct 1 mol 3-isocyanatopropyltriethoxysilane nmol (n is an integer of 1 ≦ n ≦ 2) Example 4 Diethylenetriamine 1 mol Glycidyl (meth) acrylate 3-nmol 3-glycidoxypropyltrimethoxysilane nmol (n is 1 ≦ n ≦ 3) Example 5 Triethylenetetramine 1 mol Glycidyl (meth) acrylate 4-nmol 3-glycidoxypropyltrimethoxysilane nmol (n is 1 ≦ n ≦ 4 Example 6 diaminodiphenylmethane 1 mol glycidyl (meth) acrylate 4-n mol 3-glycidoxypropyltrimethoxysilane n mol (n is an integer of 1 ≦ n ≦ 4) Example 7 m-xylylenediamine 1 mol glycidyl (Meth) acrylate 4-nmol 3-glycidoxypropyltrimethoxysilane nmol (n is an integer of 1 ≦ n ≦ 4) Example 8 Pentaoxypropylenediamine 1 mol Glycidyl (meth) acrylate 4-nmol 3-glyc Sidoxypropyltrimethoxysilane n mol (n is an integer of 1 ≦ n ≦ 4) Example 9 3-aminopropyltrimethoxysilane 1 mol Glycidyl (meth) acrylate 2 mol Example 10 3- (2-Aminoethyl) aminopropylmethyl Dimethoxysilane 1 mol glycy (Meth) acrylate 3 mol Example 11 Triethylene glycol diacrylate 1 mol Trimethoxysilane 1 mol Example 12 m-xylylenediamine 1 mol Glycidyl (meth) acrylate 4-n mol Allyl glycidyl ether n mol (n is 1 ≦ n ≤4 integer) and above addition reaction product and 3-mercaptopropyltrimethoxysilane nmol Example 13 trimethylolpropane trimethacrylate 1 mol 3-mercaptopropyltrimethoxysilane nmol (n is an integer of 1≤n≤2) Example 14 Glycerin dimethacrylate 1 mol Hexamethyldisilazane 0.5 mol Example 15 Ethylene glycol diglycidyl ether / methacrylic acid adduct 1 mol Hexamethyldisilazane 1 mol Example 16 p-hydroxystyi Len 1 mol Vinyltris (methylethylketoxime) silane 1 mol

The second non-hydrolyzable silyl group means a non-reactive silyl group, and examples thereof include an alkylsilyl group and an allylsilyl group. As the ethylenically unsaturated group compound having a non-hydrolyzable silyl group, if the non-reactive silyl group and the photopolymerizable or photocrosslinkable ethylenically unsaturated group are present in the same molecule The molecular structure thereof is not limited, but the following compounds are generally used because of their ease of synthesis and availability.

Specific examples are shown below, but the present invention is not limited thereto.

Example 17 m-Xylylenediamine 1 mol Glycidyl (meth) acrylate 4-n mol Allyl glycidyl ether n mol (n is an integer of 1 ≦ n ≦ 4) The above addition reaction product and trimethoxysilane n mol Example 18 2-Hydroxypropyl (meth) acrylate 3 mol Methyltriacetoxysilane 1 mol Example 19 α, ω-bis (3-aminopropyl) hexadimethylsiloxane 1 mol Glycidyl methacrylate 4-n mol Methylglycidyl ether n mol (n is 0 ≦ n ≦ 4) Example 20 1,3-bis (3-aminopropyl) tetramethylmethyldisiloxane 1 mol glycidyl methacrylate 4-n mol methyl glycidyl ether n mol (n is 0 ≦ n ≦ 4) integer)

In addition to these, bis (aminopropyldimethylsilyl) benzene / glycidyl methacrylate =
A 1/4 molar ratio addition reaction product and the like are also mentioned as examples of the ethylenically unsaturated compound having an organic silyl group useful in the present invention.

In addition to the ethylenically unsaturated compound having an organic silyl group described above, a small amount of polydimethylsiloxane, silicone resin, various known modified polydimethylsiloxanes, polyether modified polydimethylsiloxane, silicone (meta ) It is also possible to add silicone compounds such as acrylates. In particular, addition of a small amount of silicone (meth) acrylate is effective from the viewpoint of sensitivity adjustment.

Specific examples of the silicone (meth) acrylate include 1,3-bis (3-methacryloxypropyl) -1,1,3,3, -tetramethyldisiloxane,
3-methacryloxypropylmethyldimethoxysilane,
1- (3-methacryloxypropyl) 1,1,3,3,
3-pentamethyldisiloxane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltris (trimethylsiloxy) silane, α, ω-methacryloxypropylpolydimethylsiloxane, poly (methacryloxypropylmethyl-co-dimethyl) Examples thereof include siloxane.

In the photosensitive layer used in the present invention, known monomers or oligomers may be added for the purpose of adjusting sensitivity in addition to the monomers having these specific structures and functions.

Specific examples of such a monomer or oligomer are shown below.

Alcohols (ethanol, propanol, hexanol, octanol, cyclohexanol, glycerin, trimethylolpropane, pentaerythritol, isoamyl alcohol, lauryl alcohol, stearyl alcohol, butoxyethyl alcohol, ethoxyethylene glycol, methoxyethylene glycol, methoxypropylene). (Meth) acrylic acid esters of glycol, phenoxyethanol, phenoxydiethylene glycol, tetrahydrofurfuryl alcohol, etc., carboxylic acids (acetic acid, propionic acid, benzoic acid, acrylic acid, methacrylic acid, succinic acid, maleic acid, phthalic acid, tartaric acid, citric acid) Acid) and glycidyl (meth) acrylate or tetraglycidyl-m-xylylenediamine or tet Addition reaction product of glycidyl -m- tetrahydroxy Li diamine, amide derivatives (acrylamide, methacrylamide, n- methylolacrylamide, methylenebisacrylamide, etc.),
Examples thereof include addition reaction products of epoxy compounds and (meth) acrylic acid.

More specifically, Japanese Patent Publication No. 48-4170.
No. 8, Japanese Patent Publication No. 50-6034, Japanese Patent Laid-Open No. 51-
Urethane acrylates described in JP-A-37193, JP-A-48-64183 and JP-B-49-43.
191 and Japanese Patent Publication No. 52-30490, polyester acrylates, polyfunctional epoxy (meth) acrylates obtained by reacting an epoxy resin with (meth) acrylic acid, and N-methylol described in US Pat. No. 4,540,649. Examples thereof include acrylamide derivatives. Furthermore, Japan Adhesive Association magazine VOL.20, No.7, p300-308
The photocurable monomers and oligomers introduced in can be used.

Next, the photosensitizer which is the greatest feature of the present invention will be described.

The photosensitizer used in the present invention contains a mixture of photosensitizers selected from the following groups (I) to (III), preferably in a specific composition range. Characterize. (I) Bis (alkylamino) benzophenone (II) Thioxanthone derivative (III) Compound having absorption maximum in wavelength region beyond 400 nm

The bis (dialkylamino) benzophenone of the group (I) means a compound represented by the following general formula (7).

[Chemical 3] (However, R ¹ , R ² , R ³ , and R ⁴ represent an alkyl group having 1 to 20 carbon atoms.) Specific examples include 4,4′-bis (dimethylamino) benzophenone and 4,4′-bis. (Diethylamino) benzophenone, 4,4'-bis (dipropylamino) benzophenone, 4,4'-bis (piperidine) benzophenone and the like can be mentioned.

The thioxanthone derivative of group (II) means a compound represented by the following general formula (8).

[Chemical 4] (However, R ⁵ , R ⁶ , R ⁷ , and R ⁸ are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, an alkenyl group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Represents a functional group selected from an aralkyl group and may be the same or different.) Specific examples include 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, 2
-Laurylthioxanthone, 3-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone,
2,4-diisopropylthioxanthone, 3,4-dicarboxyoctylthioxanthone, 2-methyl-3'-
Carboxylauryl thioxanthone etc. are mentioned.

Examples of the compound (III) having an absorption maximum in the wavelength region exceeding 400 nm include acridone derivatives. The acridone derivative means a compound represented by the following general formula (9).

[Chemical 5] (However, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ are hydrogen atoms,
It represents a functional group selected from a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, an alkenyl group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, and an aralkyl group, which may be the same or different. ) As a specific example, 1-chloro-N-methylacridone,
1-bromo-N-methylacridone, 3-chloro-N-
Methylacridone, 2-chloro-N-butylacridone, 2-chloro-N-methylacridone, 3-chloro-
N-benzylacridone, 4-chloro-N-methylacridone, 2,3-dichloro-N-methylacridone,
2,6-dichloro-N-methylacridone, 2,6-dichloro-N-butylacridone, 2-chloro-N-allylacridone, 3-chloro-N-benzylacridone,
N-benzylacridone, N-butylacridone, N-
Examples include ethyl acridone.

By containing a compound having an absorption maximum in the wavelength region of more than 400 nm of the group (III), the sensitivity of the lithographic printing plate to a metal halide lamp, which is a general-purpose exposure light source, and the burning of film edges and dust are improved. The flying performance can be improved.

The addition amount of these photosensitizers is extremely important in that the effects of the present invention can be efficiently exhibited. %, Preferably 6 to 30% by weight, and the addition amount of the photosensitizer belonging to each group is (I) 0.1 to 5% by weight (II) 0.1 to 20% by weight (III) 0.1. 1 to 15% by weight Further, it is particularly preferable that the composition range is (I) 1 to 5% by weight (II) 3 to 15% by weight (III) 2 to 10% by weight.

When the photosensitizer of each group is added within the above composition range, there is substantially no difference from the known examples of the two-component mixture system, and above the composition range, the photosensitizing effect is saturated, and The layer is excessively plasticized, the photosensitive layer tends to be brittle and printing durability tends to be deteriorated, and it is economically disadvantageous to use a large amount of an expensive photosensitizer.

Specific examples of combinations and composition ranges of photosensitizer compositions which are particularly preferably used among the photosensitizer compositions preferably used in the present invention are shown below.

The maximum absorption wavelength of the compound (III) is as follows.

2-chloro-N-butylacridone 411 nm 2,6-dichloro-N-butylacridone 411 nm N-butylacridone 402 nm

[Table 1]

[Table 2] In addition to the photosensitizers having these specific structures and combinations, known photosensitizers can be added in small amounts within the range that does not impair the effects of the present invention.

It is also possible to add various additives such as dyes and pigments, pH indicators, leuco dyes, surfactants, organic acids, polymerization inhibitors and photoacid generators to the photosensitive layer used in the present invention. is there.

In particular, the addition of an organic acid is preferably added from the viewpoint of controlling the adhesion reaction and photopolymerization reaction of the above-mentioned ethylenically unsaturated compound having an organic silyl group. For example, acetic acid, propionic acid, benzoic acid, acrylic acid, methacrylic acid, succinic acid, maleic acid, phthalic acid, tartaric acid, citric acid and the like. It is also preferable to add a small amount of a known metal catalyst represented by dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dioctoate, etc. to the photosensitive layer.

Examples of the polymerization inhibitor include hydroquinone, p-methoxyphenol, di-t-butylcresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-t-butylphenol). , 2,2'-methylenebis (4-methyl-
6-t-butylphenol), 2-mercaptobenzimidazole, phenothiazine, tempol and the like are useful.

Further, a known diazo compound may be added to the photosensitive layer for the purpose of improving the adhesion between the photosensitive layer and the primer layer.

Further, for the purpose of improving the coatability of the photosensitive layer composition, it is also preferable to add a fluorinated surfactant.

Known resins and inorganic powders are preferably added as a shape-maintaining filler (polymer or inorganic powder) to the photosensitive layer used in the present invention.

That is, (meth) acrylic acid compound copolymer, crotonic acid compound copolymer, maleic acid compound copolymer, partially esterified maleic acid compound copolymer such as rosin modified, acidic cellulose derivative, Polyvinylpyrrolidone, polyethylene oxide, alcohol-soluble nylon, polyester resin, unsaturated polyester resin, polyurethane, polystyrene, epoxy resin, phenoxy resin, polyvinyl butyral, polyvinyl formal, polyvinyl chloride, polyvinyl alcohol, partially acetalized polyvinyl alcohol, water-soluble nylon ,
Water-soluble urethane, gelatin, water-soluble cellulose derivative and the like can be used alone or in combination of two or more kinds.

Further, a polymer compound having a photopolymerizable or photocrosslinkable olefinically unsaturated double bond group in its side chain may be used alone or in combination with two or more of the above polymers.

Specifically, allyl (meth) acrylate / (meth) acrylic acid / another addition-polymerizable vinyl monomer copolymer, if necessary, proposed in JP-A-59-53836 and its alkali. Metal salts or amine salts, hydroxyethyl (meth) acrylate / (meth) acrylic acid / alkyl (meth) acrylate copolymers proposed in JP-B-59-45979, and alkali metal salts or amine salts thereof ( Those obtained by reacting (meth) acrylic acid chloride, JP-A-59-7104
No. 8 proposed by adding maleic anhydride copolymer to pentaerythritol triacrylate by half-esterification, its alkali metal salt or amine salt, styrene / maleic anhydride copolymer and monohydroxyalkyl (Meth) acrylate and / or polyethylene glycol mono (meth) acrylate and / or polypropylene glycol mono (meth) acrylate added by half-esterification, its alkali metal salt or amine salt, (meth) acrylic acid copolymer, A part of carboxylic acid of crotonic acid copolymer reacted with glycidyl (meth) acrylate, and its alkali metal salt or amine salt, hydroxyalkyl (meth) acrylate copolymer, polyvinyl formal and / or polyvinyl butyra Those obtained by reacting maleic anhydride and itaconic anhydride in Le, and an alkali metal salt or amine salt, hydroxyalkyl (meth) acrylate /
The (meth) acrylic acid copolymer further reacted with an addition reaction product of 2,4-tolylene diisocyanate / hydroxyalkyl (meth) acrylate = 1/1,
And its alkali metal salts or amine salts, JP-A-59-
Japanese Unexamined Patent Publication (Kokai) No. 53836 discloses a (meth) acrylic acid copolymer partially reacted with allyl glycidyl ether, an alkali metal salt or amine salt thereof, and a (meth) allyl acrylate / sodium styrene sulfonate copolymer. , Vinyl (meth) acrylate / sodium styrene sulfonate copolymer, (meth) allyl acrylate / acrylamide / 1,1-dimethylethylene sodium sulfonate copolymer, vinyl (meth) acrylate / acrylamide / 1,1 -Sodium dimethylethylene sulfonic acid copolymer, 2-allyloxyethyl (meth) acrylate / methacrylic acid copolymer, 2-
Examples thereof include allyloxyethyl (meth) acrylate / 2-methacryloxyethyl hydrogen succinate copolymer.

The proportion of these polymers in the photosensitive layer may be 20 to 97% by weight, preferably 40 to 80% by weight, based on the total composition of the photosensitive layer.

The photosensitive layer used in the present invention generally has the following composition ratio.

Compound (Monomer) Represented by Formula (3) 1 to 50% by Weight Monomer or Oligomer Other than (1) 1 to 50% by Weight Selected from the groups (I) to (III) described above. Photosensitizer 0.3-40% by weight Filler for shape retention 20-80% by weight Other additives 0-10% by weight

The total amount of the above-mentioned monomer or oligomer components is preferably 10 to 80% by weight, more preferably 10 to 50% by weight. If the monomer or oligomer component is excessively present in the photosensitive layer, the shape retention of the photosensitive layer will be insufficient, and if it is too small, image reproducibility will be poor.

When a silicone gum composition crosslinkable by addition reaction is used in the silicone rubber layer, it is preferable to add a known polymer having an allyl group.

As the inorganic powder, silica particles are preferable,
The silica particles can be surface-treated with a known silane coupling agent.

The film thickness of the photosensitive layer used in the present invention is preferably 0.1 to 100 g / m ^{2 in} dry weight,
The range of 5 to 10 g / m ² is more preferable. If the film thickness is too thin, defects such as pinholes are likely to occur during coating, while if it is too thick, it is disadvantageous from the economical point of view such as drying and amount of the coating film.

The substrate of the lithographic printing plate used in the present invention must be one that can withstand the flexibility attached to an ordinary lithographic printing machine and the load applied during printing. Typical examples are metal plates made of aluminum, copper, iron, etc.,
Examples thereof include plastic films such as polyester film and polypropylene film, coated paper, and rubber sheets.

The substrate may be a combination of the above materials, and a waterless planographic printing plate having a primer layer for preventing halation, dyeing an image and improving printing characteristics on these substrates. Is preferably laminated.

Next, the primer layer will be described.

As the primer layer, for example, Japanese Patent Laid-Open No.
Various photosensitive polymers proposed in Japanese Unexamined Patent Publication No. 0-22903 are exposed and cured before laminating a photosensitive layer, and a methacrylic phosphorus-containing monomer proposed in JP-A-4-322181 is used as a photosensitive layer. Of the methacrylic epoxy compound proposed in Japanese Patent Laid-Open No. 7049/1990, which is exposed and cured before being laminated. Fifty
Heat-cured epoxy resin proposed in Japanese Patent Laid-Open No. 760, gelatin hardened in Japanese Patent Application Laid-Open No. 63-133151, Japanese Patent Laid-Open No. 1-28.
2270 and Japanese Patent Laid-Open No. 2-21072 can be used. Other than this, a casein-hardened casein is also effective.

For the purpose of further softening the primer layer, polyurethane, polyamide, styrene / butadiene rubber, carboxy-modified styrene / butadiene rubber, acrylonitrile / butadiene rubber, carboxy-modified acrylonitrile / having a glass transition temperature of room temperature or lower is added to the primer layer. Polymers such as butadiene rubber, polyisoprene rubber, acrylate rubber, polyethylene, chlorinated polyethylene and chlorinated polypropylene may be added.

The addition ratio is arbitrary, and the primer layer may be formed only by the additive as long as it is within a range in which the film layer can be formed. In addition, for these primer layers, a dye, a pH indicator, an exposure printing-out agent, a photochromic compound, a photopolymerization initiator, an adhesion aid (for example, a polymerizable monomer, a diazo resin, a silane coupling agent) can be used in accordance with the above purpose. Agents, titanate coupling agents, aluminum coupling agents, zirconia coupling agents, boron coupling agents, etc.), white pigments, and additives such as silica particles.

The film thickness of the primer layer used in the present invention is preferably in the range of 0.1 to 20 g / m 2 in terms of dry weight.
The range of 10 g / m ² is more preferable.

On the surface of the ink repellent layer of the waterless lithographic printing plate precursor having the above-mentioned constitution, a suitable protective layer is coated on the ink repellent layer for the purpose of protecting the ink repellent layer. It can also be formed or laminated with a protective film. In addition, the protective layer may contain a photobleaching substance for the purpose of protecting the photosensitive layer from exposure to light (meaning that the non-irradiated portion is originally irradiated with light other than the exposure light source). it can.

Specific examples of the protective film include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate and cellophane. Further, in order to improve the vacuum adhesion in the baking frame at the time of image exposure, it is also preferable that these protective films are matt-treated on the surface or a plastic layer containing silica particles or the like is applied and laminated on the surface of the protective film. Done.

Next, a method for producing a waterless planographic printing plate precursor according to the invention will be described. An ordinary coater such as a reverse roll coater, an air knife coater, and a Mayer bar coater, or a spin coater such as a whaler was used to apply a primer layer composition to the substrate as needed, followed by curing at 100 to 300 ° C. for several minutes. After that, the photosensitive layer composition coating liquid is applied, dried at a temperature of 50 to 150 ° C. for several minutes and thermally cured if necessary, and the silicone gum composition is applied thereon, and the temperature of 50 to 150 ° C. for a few minutes. It is formed by heat treatment and rubber curing. After that, a protective film is laminated if necessary.

Next, the exposure and development step of the waterless planographic printing plate precursor according to the invention will be described.

The waterless planographic printing plate precursor according to the invention is preferably used as a plate material for positive working. The plate material is image-exposed with a usual exposure light source through a positive film which is vacuum-contacted. Examples of the light source used in this exposure step include a high pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, and a fluorescent lamp. After such normal exposure, the plate surface is rubbed with a developing pad or a brush containing a developer described below, the silicone rubber layer in the unexposed area is removed and the photosensitive layer is exposed, and the ink receiving part ( The image area) is exposed and becomes a printing plate.

As the developing solution used in the present invention, a known developing solution can be used, and a developing solution capable of appropriately dissolving or swelling the photosensitive layer is preferable. For example, aliphatic hydrocarbons (hexane, heptane, "isopar" E, H, G (ESSO
(Product name of isoparaffin hydrocarbons made from gasoline, gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated hydrocarbons (tricrene, etc.), etc. The thing which added at least 1 type of polar solvent is used preferably.

Alcohols (methanol, ethanol,
Propanol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol,
Tripropylene glycol, polypropylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, hexylene glycol, 2-ethyl-1,3
-Hexanediol, etc.) Ethers (ethylene glycol monoethyl ether,
Diethylene glycol, monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, diethylene glycol mono-
2-ethylhexyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monoethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, dioxane,
Tetrahydrofuran, etc. Ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetone alcohol, etc.) Esters (ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, butyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, Diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether ateate, etc.) Carboxylic acid (2-ethylbutyric acid, caproic acid, caprylic acid, 2-ethylhexanoic acid, capric acid, oleic acid,
(Lauric acid, etc.)

It is also possible to freely add water or a known surfactant to the above organic solvent type developer composition. Further, an alkaline agent, for example, sodium carbonate, monoethanolamine, diethanolamine, triethanolamine, sodium silicate, potassium silicate, potassium hydroxide, sodium borate or the like can be added.

Further, well-known basic dyes such as crystal violet, Victoria pure blue, and Astrazone red, acid dyes, and oil-soluble dyes may be added to these developers to dye the image area simultaneously with development. it can.

When developing the waterless planographic printing plate used in this study, an automatic developing machine commercially available from, for example, Toray Co., Ltd. is used, and the plate surface is pretreated with the above developing solution. After that, the plate surface is rubbed with a rotating brush while showering with tap water or the like, so that suitable development can be performed. Further, it is possible to develop by spraying hot water or steam on the plate surface instead of the above developing solution.

[0110]

The present invention will be described in more detail with reference to the following examples.

Examples 1 to 19 An aluminum plate having a thickness of 0.3 mm (manufactured by Sumitomo Light Metal Co., Ltd.) degreased by a usual method was coated with the following primer composition,
After heat treatment at 200 ° C. for 2 minutes, a primer layer of 5 g / m ² was applied. <Solid component: coating concentration 12%> (1) Polyurethane resin (“Samprene” LQ-SZ18; Sanyo Chemical Industry Co., Ltd.) 75% by weight (2) Blocked isocyanate (“Takenate” B830; Takeda Pharmaceutical Co., Ltd.) ) 15% by weight (3) Epoxy / urea resin 10% by weight <Solvent component> (4) Dimethylformamide

Subsequently, a photosensitive composition having the following composition was dried thereon at 120 ° C. for 1 minute to form a photosensitive layer of 3 g / m ^{2 on} the surface. <Solid component: coating concentration 15%> (1) Polyurethane obtained by reaction of polyester polyol of adipic acid with hexane-1,6-diol and 2,2-dimethylpropane-1,3-diol and isophorone diisocyanate 49-α wt% (2) pentaoxypropylene diamine / glycidyl methacrylate / methyl glycidyl ether = 1/3/1 mol ratio addition reaction product 15 wt% (3) m-xylylenediamine / glycidyl methacrylate / methyl glycidyl ether = 1 / 2/2 mol ratio addition product 15 _{wt% (4) CH 2 = CHCOO-} (CH 2) 9 -OCOCH = CH 2 8 wt% (5) trioxypropylene diamine / glycidyl methacrylate / 3-glycine de trimethoxy Methoxysilane = 1/3/1 mol ratio Addition reaction product 2% by weight (6) Light enhancement Agent (Table 1-5 see) alpha wt% (7) Victoria Pure Blue BOH naphthalenesulfonic acid salt 0.5 wt% (8) 0.5 wt% maleic <Solvent Component> (9) Propylene glycol monomethyl ether

Subsequently, a condensation reaction crosslinkable silicone rubber layer composition having the following composition was coated on the photosensitive layer with a bar coater and heated and cured at 115 ° C. for 2 minutes to coat a silicone rubber layer of ² g / m ^2. I set it up. <Solid component: 8%> (1) Polydimethylsiloxane with hydroxyl groups at both ends (degree of polymerization: up to 700) 90% by weight (2) Tris (methylethylketoxime) vinylsilane 9.8% by weight (3) Dibutyltin dilaurate 0.2% by weight <Solvent component> (4) "Isopar" E

On the laminated plate obtained as described above, a 12-micron-thick, single-sided matted biaxially oriented polypropylene film was laminated using a calendar roller so that the non-matted surface was in contact with the silicone rubber layer. Then, a positive type waterless planographic printing plate precursor was obtained.

Image evaluation is a positive film having a halftone dot of 200 lines / inch 1 to 99%, a gray scale (G / S) having an optical density difference of 0.15, and model dust (fiber dust, film dust, etc.), model film Extend the edge on the polyester film for staking, Nuark FT261V
UNDS ULTRA-PLUS FIIPTOP PLATEMAKER A vacuum exposure machine was used for 30 seconds of vacuum contact, followed by 30 count exposure and peeling of the laminate film.

After that, an automatic processor (manufactured by Toray Industries, Inc .: TWL)
1160) for 1 minute in a PP-F pretreatment liquid (Toray Industries, Inc .: pretreatment liquid for automatic developing machine) having a liquid temperature of 40 ° C., and a developing brush in pure water having a liquid temperature of 25 ° C. The silicone rubber layer in the unexposed area was peeled off and removed to obtain a printing plate.

The results are shown in Table 3.

[0118]

[Table 3] Comparative Examples 1 to 9 Only the composition of the photosensitizer was changed to Table 4 below, and a waterless lithographic printing plate was prepared in the same manner as in the other examples, and similarly developed with an automatic processor to obtain a printing plate.

The results are shown in Table 5.

[0120]

[Table 4]

[Table 5]

[0121]

The waterless lithographic printing plate precursor of the present invention contains three kinds of photosensitizers having a specific structure in the photosensitive layer, preferably in combination in a specific composition range, so that a simple addition is possible. Expressing a dramatic improvement in sensitivity that cannot be explained by syntheticity,
Further, excellent image reproducibility is exhibited from the highlight portion to the shadow portion, and the burn-off property of film edges and dust is improved.

Claims (6)

[Claims] 1. A waterless planographic printing plate comprising at least a photosensitive layer and an ink repellent layer provided in this order on a substrate, wherein the photosensitive layer is one of the following groups (I), (II) and (III). A waterless planographic printing plate precursor comprising at least one photosensitizer selected from each. (I) Bis (alkylamino) benzophenone (II) Thioxanthone derivative (III) Compound having absorption maximum in a wavelength region exceeding 400 nm 2. The composition range of (I), (II) and (III) in the photosensitive layer is (I) 0.1 to 5% by weight (II) 0.1 to 20% by weight (III) 0.1. The waterless planographic printing plate precursor according to claim 1, wherein the content is 1 to 15% by weight. 3. The waterless planographic printing plate precursor according to claim 1, wherein (III) is an acridone derivative. (I) Bis (alkylamino) benzophenone (II) Thioxanthone derivative (III) Acridone derivative 4. The waterless planographic printing plate precursor according to claim 3, wherein (III) is 2-chloro-N-butylacridone. 5. (I), (II) and (III) are (I) 4,4'-bis (diethylamino) benzophenone (II) 2,4-diethylthioxanthone (III) 2-chloro-N-, respectively. The waterless planographic printing plate precursor according to claim 1, which is butyl acridone. 6. The composition range of (I), (II) and (III) in the photosensitive layer is (I) 1 to 5% by weight (II) 3 to 15% by weight (III) 2 to 10% by weight. The waterless planographic printing plate precursor according to claim 5, wherein