JP2000047377A - Original plate of waterless planographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve image reproducibility and printing resistance even in the case of a photomechanical process including exposure at a low temp., in particular <=20 deg.C by incorporating a specified monomer, a photopolymn. initiator and a high molecular compd. having film forming ability into a photosensitive layer. SOLUTION: A photosensitive layer and a silicone rubber layer are laminated in this order on a substrate. The photosensitive layer contains a photopolymerizable unsatd. monomer of the formula CH2=C(R)-CO-O-(CH2CH2 O)1-(CH2CH(CH3)-O)m-(CH2CH2O)n-CO-C(R)=CH2, a photopolymn. initiator and a high molecular compd. having film forming ability. In the formula, R is H or methyl, (m) is a real number of 3-12, (l) and (n) are each a real number of 1-5, 5<(l+m+n)<16, m>l+n. The pref. contents of the unsatd. monomer, the photopolymn. initiator and the high molecular compd. are 1.0-100 pts.wt., 0.1-20 pts.wt. and 0.01-100 pts.wt., respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing plate precursor without water. More specifically, the present invention relates to a water-free lithographic printing plate precursor. More specifically, a photosensitive layer capable of receiving ink and a silicone rubber layer capable of repelling ink are provided in this order on a substrate. It relates to a waterless planographic printing plate precursor.

[0002]

2. Description of the Related Art Various lithographic printing plate precursors for lithographic printing without water for performing lithographic printing without using dampening water have been proposed. Among them, those in which a photosensitive layer and a silicone rubber layer are sequentially provided on a substrate have extremely excellent performance, for example, Japanese Patent No. 273939.
In No. 2, a waterless lithographic printing plate precursor having high sensitivity and excellent developability can be developed with water or an inexpensive and low-risk developer containing water or water as a main component in Japanese Patent No. 2739387.
A waterless lithographic printing plate having good image part developability and good tone reproducibility has been provided.
No. 9383, the degree of cure of the silicone rubber layer and the adhesion between the silicone rubber layer and the photosensitive layer were appropriately controlled.
A waterless lithographic printing plate precursor excellent in image reproducibility and printing durability is provided.

[0003] However, when a plate is made by exposing at a low temperature during image formation, the adhesion between the photosensitive layer and the silicone rubber layer is not sufficient, and satisfactory image reproducibility, particularly in shadow reproducibility, cannot be obtained.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a waterless planographic printing plate precursor which is excellent in image reproducibility and printing durability even when plate making is performed by exposing at a low temperature, especially at a temperature of 20 ° C. or less. That is.

[0005]

To solve the above-mentioned problems, the present invention mainly has the following constitution. That is, a "waterless lithographic plate comprising: a substrate, a photosensitive layer, and a silicone rubber layer laminated in this order, and the photosensitive layer contains the following three components (A), (B), and (C). (A) at least one monomer represented by the following general formula (I): CH ₂ = C (R) -CO-O- (CH ₂ CH ₂ O) l- (CH ₂ CH) (CH ₃ ) -O) m- (CH ₂ CH ₂ O) n-CO-C (R) = CH ₂ (I) (wherein R is a hydrogen atom or a methyl group and is the same or different M is 3 to 12, l and n are 1
５5, which may be the same or different. 5 <(l + m + n) <16, and m> l + n. (B) a photopolymerization initiator, and (C) a polymer compound capable of forming a film.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

[0007] The substrate of the lithographic printing plate must be flexible and can withstand the load applied during printing, which is attached to an ordinary lithographic printing press. As a typical one,
Examples include a metal plate such as aluminum, copper, and iron, a plastic film such as a polyester film and a polypropylene film, coated paper, and a rubber sheet. Further, the substrate may be a composite of the above-mentioned materials, and a primer layer is preferably laminated on these substrates to prevent halation in a waterless lithographic printing plate, dye an image and improve printing characteristics. Is done.

[0008] A primer layer can be provided between the substrate and the photosensitive layer for the purpose of improving the adhesion and the plate inspection. As the primer layer, for example, JP-A-60-22
JP-A-4-322, in which various photosensitive polymers disclosed in JP-A No. 903 are exposed and cured before providing a photosensitive layer.
JP-A No. 181-181, in which a methacrylic phosphorus-containing monomer is exposed and cured before providing a photosensitive layer.
No. 7049, a methacrylic epoxy compound exposed and cured before providing a photosensitive layer.
JP-A-2-50760 obtained by heat-curing an epoxy resin, JP-A-63-133151 discloses a hardened gelatin, JP-A-1-282270 and JP-A-2-21072. Those using a certain urethane resin are exemplified.

[0009] In addition, a casein hardened material is also effective. In order to further soften the primer layer,
Polyurethane, polyamide, styrene / butadiene rubber having a glass transition temperature of room temperature or lower in the primer layer,
Polymers such as carboxy-modified styrene / butadiene rubber, acrylonitrile / butadiene rubber, carboxy-modified acrylonitrile / butadiene rubber, polyisoprene rubber, acrylate rubber, polyethylene, and chlorinated polypropylene may be added. The addition ratio is arbitrary, and the primer layer may be formed only with the additives as long as the film layer can be formed. In addition, these primer layers, according to the above purpose, dye, pH indicator,
Exposure baking agent, photochromic compound, photopolymerization initiator, adhesion assistant (eg, polymerizable monomer, diazo resin, silane coupling agent, titanate coupling agent, aluminum coupling agent, zirconia coupling agent, boron coupling Agents, etc.), additives such as white pigments and silica particles.

The thickness of the primer layer used in the present invention is preferably in the range of 0.1 to 20 g / m ² by dry weight, and more preferably in the range of 1 to 10 g / m ² .

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

When image formation is performed in a positive type, a photocurable layer is mainly used as a photosensitive layer for positive working. In the present invention, a photopolymerizable layer is used as the photocurable layer.

The content of each component is not particularly limited, but is preferably contained in the following component ratio from the viewpoint of image reproducibility and the like. (A) Photopolymerizable unsaturated monomer 1.0 to 100 parts by weight (B) Photopolymerization initiator 0.1 to 20 parts by weight (C) Polymer compound having film forming ability 0.01 to 100 parts by weight The present invention It is essential that the photosensitive layer of the lithographic printing plate precursor contains a monomer represented by the general formula (I). By containing the monomer represented by the general formula (I), excellent image reproducibility at low temperature exposure and the like can be achieved.

CH ₂ = C (R) -CO-O- (CH ₂ CH ₂ O) l- (CH ₂ CH (CH ₃ ) -O) m- (CH ₂ CH ₂ O) n-CO-C ( R) = CH ₂ (I) (wherein R is a hydrogen atom or a methyl group and may be the same or different; m is 3 to 12, l and n are 1
５5, which may be the same or different. 5 <(l + m + n) <16, and m> l + n. In addition, the monomer represented by the general formula (I) may be a single substance or a mixture. In the case of a mixture, l, n and m are their average values.

When l + m + n is 5 or less, the composition volatilizes during drying to lower the concentration, causing variations in the plate, and adhesion to the side walls of the oven becomes dust defects, and a good plate material cannot be obtained. . In addition, the reaction speed is slow at 16 or more,
The desired sensitivity cannot be obtained.

The monomer represented by the general formula (I) is commercially available as a mixture under the following trade names, for example.

[0017]

Embedded image In addition, known monomers and the like can be used in combination with the monomer of the general formula (I). When a known monomer is used in combination, it is preferable to use the monomers of general formulas (II) and (VI) in combination.

R ¹ R ² N- (X ¹ ) p- (X ² ) q-NR ³ R ⁴ (II) (wherein X ¹ and X ² are a substituted or unsubstituted ring having 1 to 20 carbon atoms) X ² represents a divalent linking group selected from formula or acyclic alkylene, substituted or unsubstituted phenylene, and substituted or unsubstituted aralkylene, and X ² represents —OE ¹ —, —SE ² —, —NH—
^{E 3 -, - CO-E} 4 -, - SO 2 -NH-E 5 - ^{a, E 1, E 2, E} 3, E 4, E
⁵ represents the same divalent linking group as X ¹ and X ² described above. p represents an integer of 1 or more, and q represents 0 or an integer of 1 or more. R ¹ ,
R ² , R ³ , and R ⁴ are selected from a hydrogen atom, a substituted or unsubstituted phenyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group, and the following formulas (III), (IV), and (V). Functional groups, which may be the same or different.
However, one molecule of compound (II) contains at least one ethylenically unsaturated group.

[0019]

Embedded image R ⁵ , R ⁶ and R ^{7 each} represent 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, a CH ₂ CHCH— group, CH ₂
= CCH ₃ - represents a group. Y represents -CO-O-, -CO-NH-, a substituted or unsubstituted phenylene group. X ³ , X ⁴ and X ⁵ are X ¹ ,
Is the same as that of X ^2. m and n represent 0 or 1. In the above, as the substituent, an alkyl group having 1 to 6 carbon atoms,
Examples include a halogen atom, a hydroxyl group, and an aryl group. )

Embedded image (Wherein L ^{1 to} L ⁶ are a hydroxyl group, a glycidyloxy group, an acryloxy group, a methacryloxy group, a 2-hydroxy-3-
Acryloxypropyloxy group, 2-hydroxy-3-
At least one selected from the group of methacryloxypropyloxy groups, which may be the same or different, at least one of L ^{1 to} L ⁶ is 2-hydroxy-3
An acryloxypropyloxy group and / or a 2-hydroxy-3-methacryloxypropyloxy group. Specifically, the monomers of the general formula (II) include N, N, N ', N'
-Tetra (2-hydroxy-3-methacryloxypropyl) polyoxypropylenediamine, and the monomer of the general formula (VI) includes 1,2,4,6-tetra- (2
-Hydroxy-3-methacryloxypropyloxy)-
3,5-dihydroxyhexane and the like.

In addition to the above-mentioned monomers, other known monomers and oligomers, a small amount of polydimethylsiloxane, silicone resin, various known modified polydimethylsiloxanes, polyether-modified polydimethylsiloxane, silicone (meth) acrylate, etc. It is also possible to add a silicone compound of For example,
JP-A-8-41708, JP-B-50-6034,
Urethane acrylates described in JP-A-51-37193, polyester acrylates and epoxy resins described in JP-A-48-64183, JP-B-49-43191 and JP-B-52-30490. -Functional epoxy (meth) acrylate obtained by unreacting methacrylate and (meth) acrylic acid, US Patent No. 45064
N-methylol acrylamide derivative described in No. 9 and the like. In addition, the Journal of the Japan Adhesion Association
Vol. 20, No. 7, pages 300 to 308, photocurable monomers and oligomers such as polyol polyacrylates, polyester acrylates, epoxy acrylates, and urethane acrylates can also be used.
Further, the photosensitive layer may contain an ethylenically unsaturated compound having an organic silyl group.

When a free acid is used as a raw material for the synthesis of an ethylenically saturated monomer, the reaction mixture may have an unreacted free acid.

Next, the photopolymerization initiator used in the present invention will be described. The photopolymerization initiator used in the present invention is not particularly limited as long as it is a known one, and two or more kinds can be used in combination. Specifically, various benzophenone-based compounds, substituted thioxanthone-based compounds, substituted acridone-based compounds, vicinal polyketaldonyl compounds proposed in US Pat. No. 2,367,660, US Pat.
Α-carbonyl compounds proposed in US Pat. No. 2,661,661 and U.S. Pat.
Ether proposed in U.S. Pat.
No. 724612, which discloses an aromatic acyloin compound in which the α-position is substituted with a hydrocarbon, which is proposed in US Pat.
No. 7 and U.S. Pat. No. 2,951,758, a polynuclear quinone compound, a combination of triarylimidazole dimer / p-aminophenyl ketone proposed in U.S. Pat. No. 3,549,367, U.S. Pat.
No. 24, a benzothiazole / trihalomethyl-s-triazine compound proposed in U.S. Pat. No. 4,239,850, an acridine and phenazine compound proposed in U.S. Pat. No. 3,754,259, U.S. Pat. Oxadiazole compounds proposed in U.S. Pat.
No. 4475, U.S. Pat. No. 4,189,323,
-133428, JP-A-60-105667, JP-A-62-58241, JP-A-63-15
No. 3542, a trihalomethyl-s-triazine-based compound having a chromophore group.
Benzophenone group-containing peroxyester compounds proposed in JP-A-97401 and JP-A-60-76503.

In particular, as the photopolymerization initiator preferably used in the present invention, there are a combination of a benzophenone compound represented by Michler's ketone and a substituted thioxanthone compound represented by 2,4-diethylthioxanthone. Further, it is preferable to combine a substituted acridone compound represented by N-alkylacridone from the viewpoint of improving sensitivity and image reproducibility, particularly highlight reproducibility.

Next, the polymer compound having a film forming ability used in the present invention will be described.

The polymer compound capable of forming a film used in the present invention means a polymer compound capable of forming a film, and any known polymer compound may be used as long as the properties are satisfied. Specifically, (meth) acrylic acid compound copolymer, crotonic acid compound copolymer, maleic acid compound copolymer, partially esterified maleic acid compound copolymer such as rosin modification, 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 derivatives, etc., and these can be used alone or as a mixture of two or more.

Further, a polymer compound having a photopolymerizable or photocrosslinkable olefinically unsaturated double bond group in a side chain may be used alone or as a mixture, and may be used in combination with the above-mentioned polymer. Specifically, JP-A-59-538
No. 36, allyl (meth) acrylate / (meth) acrylic acid / as required, other addition-polymerizable vinyl monomer copolymers, and alkali metal salts or amine salts thereof. (Meth) acrylate / (meth) acrylic acid / alkyl (meth) acrylate copolymer and its alkali metal salt or amine salt (meth)
What reacted with acrylic acid chloride,
No. 71048, in which pentaerythritol triacrylate is added by half-esterification to a maleic anhydride copolymer, and an alkali metal salt or an amine salt thereof, and a styrene / maleic anhydride copolymer containing monohydroxyalkyl. (Meth) acrylate and / or polyethylene glycol mono (meth) acrylate and / or polypropylene glycol mono (meth) acrylate added by half esterification, and alkali metal or amine salts thereof, and (meth) acrylic acid copolymer Glycidyl (meth) acrylate reacted with a part of the carboxylic acid of the union or crotonic acid copolymer, and its alkali metal salt or amine salt, hydroxyalkyl (meth) acrylate copolymer, polyvinyl formal and / or Those obtained by reacting maleic anhydride and itaconic acid polyvinyl butyral, and alkali metal salts or amino salts, hydroxyalkyl (meth) acrylate / (meth) 2 acrylic acid copolymer,
4-tolylene diisocyanate / hydroxyalkyl (meth) acrylate = 1: 1 addition reaction product, further reacted with an alkali metal salt or amine salt, which is proposed in JP-A-59-53836. )
Acrylic acid copolymer partially reacted with allyl glycidyl ether and its alkali metal salt or amine salt, (meth) allyl acrylate / sodium styrene sulfonate copolymer, (meth) vinyl acrylate / styrene sulfonic acid Sodium copolymer, (meth) acrylate / acrylamide / 1,1-dimethylethylene sodium sulfonate copolymer, vinyl (meth) acrylate / acrylamide / 1,1-dimethylethylene sodium sulfonate copolymer, 2-ali Roxyethyl (meth)
An acrylate / methacrylic acid copolymer and a 2-allyloxyethyl (meth) acrylate / 2-methacryloxyethyl hydrogen succinate copolymer can be exemplified.

In addition, the photosensitive layer used in the present invention includes
It is also possible to add various additives such as dyes and pigments, pH indicators, leuco dyes, surfactants, polymerization inhibitors and photoacid generators. It is also preferable to add a fluorine-based surfactant for the purpose of improving the coating properties of the photosensitive layer composition. Further, an organic carboxylic acid or the like can be added to the photosensitive layer of the present invention. Further, from the viewpoint of controlling the reaction between the photosensitive layer and the silicone rubber layer, a small amount of a known organic metal catalyst represented by dibutyltin diacetate, dibutyltin diurarate, dibutyltin dioctoate, or the like can be added to the photosensitive layer. It is.

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

Examples of the silicone rubber layer used in the present invention include those having the following constitutions (1) condensation crosslinking type and (2) addition crosslinking type, but are not limited thereto.

(1) The condensation-crosslinked silicone rubber layer is a silicone rubber layer obtained by condensing a linear polyorganosiloxane. The polyorganosiloxane referred to in the present invention is represented by the following general formula (VII): Means the linear polyorganosiloxane to be obtained. Further, the silicone gum composition referred to in the present invention means an uncured (non-rubberized) solution composition obtained 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 cross-linking reaction under appropriate curing conditions and rubberized.

[0031]

Embedded image (Where n is an integer of 1 or more, and R ⁸ and R ^{9 each} have 1 to 10 carbon atoms)
Alkyl group, alkoxy group, aminoalkyl group, haloalkyl group, hydroxyalkyl group, carboxyalkyl group having 2 to 10 carbon atoms, cyanoalkyl group or substituted or unsubstituted aryl group having 6 to 20 carbon atoms, aryloxy group, aralkyl Group or a group selected from a hydrogen atom and a hydroxyl group, which may be the same or different. Further, it has at least one or more hydroxyl groups in the side chain of the molecule in the form of a chain terminal or a side chain. As the condensation-crosslinkable silicone gum composition, a so-called room temperature (hereinafter referred to as room temperature) obtained by adding a crosslinking agent and, if necessary, a catalyst to an organic solvent solution of the linear polyorganosiloxane represented by the above general formula (VII). It takes the form of a (low temperature) moisture cross-linking type. As the condensation-crosslinking agent used for constituting the silicone gum composition, acetoxysilane, ketoximesilane, alkoxysilane, aminosilane, amidosilane, and the like, which are represented by the following general formula (VIII), are preferably used. Usually, a crosslinking agent that reacts with a linear polyorganosiloxane having at least one or more hydroxyl groups in a molecular chain to crosslink in a condensation reaction in the form of deoxime, dealcohol, deamine, or deamidation, respectively. , In a single or mixed form, or in the form of a condensate. In particular, in the present invention, acetoxysilane,
Ketoxime silane, alkoxysilane and the like are preferably used.

R ¹⁰ m · Si · Xn (VIII) (where m and n are integers satisfying m ≧ 0 and n ≧ 1 and satisfying m + n = 4. R ¹⁰ is a substituted or unsubstituted carbon number) 1 to 20 alkyl groups, aminoalkyl groups, aminoalkyleneaminoalkyl groups, aminoalkyleneaminomethylphenethyl groups, substituted or unsubstituted carbon atoms of 6 to
Represents 20 aryl groups. X is -OR ¹¹ , -OC
OR ¹² , -ON = CR ¹³ -R ¹⁴ or -OC = CR
It is a ¹⁵ H. R ^{11 to} R ^{15 each} represent a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. The following are specific examples of the condensation reaction crosslinking agent alone or a condensate thereof. Tetramethoxysilane,
Tetraethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, dimethyldiethoxysilane,
Diethyldiethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, tetraacetoxysilane, methyltriacetoxysilane, ethyltriacetoxysilane, dimethyldiacetoxysilane, γ-aminopropyltriethoxysilane, N- (βaminoethyl)-
γ-aminopropyltrimethoxysilane, N- (βaminoethyl) -γ-aminopropyltrimethoxysilane,
N- (βaminoethyl) -γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane,
γ-chloropropyltriethoxysilane, N- (βaminoethyl) aminomethylphenethyltrimethoxysilane, N- (βaminoethyl) aminomethylphenethyltriethoxysilane, tris (methylethylketoxime) methylsilane, tris (methylethylketoxime) ethylsilane, Tris (methylethylketoxime) vinylsilane, tetrakis (methylethylketoxime) silane and the like.

Examples of the mixed catalyst include organic tin compounds, organic titanium compounds, organic aluminum compounds, organic lead compounds,
A compound selected from the group consisting of organic boron compounds and organic zirconium compounds can be used. Especially organotin compounds,
The compound selected from the group of the organic titanium compound and the organic aluminum compound is preferable from the viewpoint of efficiently exhibiting the condensation catalyst effect, and more preferably the compound selected from the group of the organic tin compound. Although the composition of the silicone rubber layer is not particularly limited, a composition in which 3 to 20 parts by weight of the above condensation reaction crosslinking agent and 0.001 to 0.05 parts by weight of the condensation catalyst are added to 100 parts by weight of the polyorganosiloxane is used. preferable.

(2) The addition-crosslinking type silicone rubber layer is made of Si
It is a silicone rubber layer crosslinked by an addition reaction between an H group and a —CH ＝ CH— group. The addition type silicone rubber layer used herein is obtained by reacting a polyvalent hydrogen organopolysiloxane with a polysiloxane compound having two or more —CH ＝ CH— bonds in one molecule. (1) Organopolysiloxane having at least two alkenyl groups (preferably vinyl groups) directly bonded to silicon atoms in one molecule (2) Organopolysiloxane having at least two SiH bonds in one molecule (3) Addition It is obtained by crosslinking and curing a composition comprising a catalyst. Ingredient (1)
The alkenyl group of may be at the terminal of the molecular chain or in the middle. Examples of the group other than the alkenyl group include, but are not limited to, a substituted or unsubstituted alkyl group and an aryl group. Component (1) may contain a small amount of hydroxyl groups. The component (2) reacts with the component (1) to form a silicone rubber layer, and also plays a role of imparting adhesiveness to the photosensitive layer. The hydroxyl group of component (2) is a molecular chain terminal,
It may be in any of the middle. The organic group other than hydrogen is selected from those similar to the component (1). It is preferable that 60% or more of the organic groups of the components (1) and (2) are methyl groups as a whole from the viewpoint of improving ink repellency. The molecular structure of the component (1) and the component (2) may be linear, cyclic, or branched, and it is preferable that at least one of the molecular weights exceeds 1,000 in terms of rubber physical properties.
Further, the molecular weight of component (1) preferably exceeds 1,000.

Component (1) includes α, ω-divinylpolydimethylsiloxane, (methylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, and component (2) includes hydroxyl groups at both terminals. Polydimethylsiloxane, α, ω-dimethylpolymethylhydrogensiloxane, (methylpolymethylhydrogensiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, cyclic polymethylhydrogensiloxane, etc. It is not limited, and may be another one.

The addition catalyst of the component (3) is arbitrarily selected from known catalysts, and is particularly preferably a platinum compound.
Platinum alone, platinum chloride, olefin-coordinated platinum and the like are used. In order to control the effect speed of these compositions, vinyl group-containing organopolysiloxanes such as tetracyclo (methylvinyl) siloxane, alcohols having a carbon-carbon triple bond, acetone, methyl ethyl ketone, methanol, ethanol, propylene glycol monomethyl ether, etc. It is also possible to add an appropriate amount of the crosslinking inhibitor.

In addition to these compositions, a known adhesion-imparting agent such as alkenyl trialkoxysilane may be added, or a hydroxyl group-containing organopolysiloxane which is a composition of a condensation type silicone rubber layer, and a terminal having a trimethylsilyl group. Silicone oil composed of dimethylpolysiloxane, dimethylpolysiloxane terminated with a trimethylsilyl group, or a hydrolyzable functional group-containing silane (or siloxane) may be added. Further, a known filler such as silica may be added to improve the rubber strength.

For the purpose of appropriately reinforcing the silicone rubber layer, the silicone gum composition may be added with known fillers, inorganic particles, silicate sol, or the like, or may be modified with known crosslinking agents having no crosslinkable functional groups. It is also possible to add a small amount of silicone oil. As a solvent for diluting and dissolving these silicone gum compositions, paraffinic hydrocarbons, isoparaffinic hydrocarbons, cycloparaffinic hydrocarbons, and aromatic hydrocarbons are used in a single or mixed form. Representative examples of these hydrocarbon solvents include fractionated petroleum products and improved products thereof. The thickness of the silicone rubber layer of the present invention is preferably in the range of 0.5 to 10 g / m ² in terms of dry weight from the viewpoint of maintaining printing durability and ink repellency and maintaining good image reproducibility. ~ 3g
/ M ² is more preferable.

On the surface of the silicone rubber layer of the waterless planographic printing plate precursor having the structure described above, an appropriate protective layer is formed on the silicone rubber layer by coating for the purpose of protecting the silicone rubber layer. It is also possible to laminate a protective film. Further, in the protective layer, for the purpose of protecting the photosensitive layer from exposure to light (meaning that light other than the exposure light source is originally irradiated to the non-irradiated portion),
A light-fading substance can be contained. Specific examples of the protective film include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate, cellophane, and the like. In addition, these protective films are preferably subjected to a matte treatment or a plastic layer containing silica particles or the like on the surface of the protective film, in order to improve the vacuum adhesion in a printing frame during image exposure. Done.

Next, a method for producing a waterless planographic printing plate precursor according to the present invention will be described. The primer layer composition is applied on the substrate using a normal coater such as a reverse roll coater, an air knife coater, or a Meyer bar coater, or a spin coater such as a wheyer as necessary, and cured at 100 to 300 ° C. for several minutes. After that, the photosensitive layer composition is applied, dried at 50 to 150 ° C. for several minutes and heat-cured if necessary, and the silicone gum composition is applied thereon,
Heat-treated at 50 to 150 ° C. for several minutes to cure the rubber and form. Thereafter, a protective film is laminated as necessary.

Next, the step of exposing and developing a waterless planographic printing plate according to the present invention will be described. The waterless lithographic printing plate as referred to in the present invention is image-exposed through a vacuum-contacted positive film or negative film by a usual exposure light source. Examples of the light source used in the exposure step include a high-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, and the like. After performing such a normal exposure, when the plate surface is rubbed with a developing pad or brush containing a developing solution described below, in the case of positive working,
The unexposed portion of the silicone rubber layer is removed to expose the photosensitive layer, and the ink receiving portion (image portion) is exposed to form a positive printing plate.
In the case of negative working, the silicone rubber layer in the exposed area is removed, the photosensitive layer is exposed, and the ink receiving area (image area) is exposed to form a negative printing plate.

As the developer used in the present invention, a known developer can be used, and a developer which appropriately dissolves or swells the photosensitive layer is preferable. For example, aliphatic hydrocarbons (hexane, heptane, “Isoper E, H or G” (ES
SO (trade name of isoparaffinic hydrocarbon), gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated hydrocarbons (trichlene, etc.), alcohols (triethylene glycol, triethylene glycol, etc.) Propylene glycol, 1,3-butylene glycol, etc.), ethers (diethylene glycol monomethyl ether, diethylene glycol-2-ethylhexyl ether, tripropylene glycol monomethyl ether, etc.), ketones (diacetone alcohols, etc.), esters (diethylene glycol monoethyl) Ether acetate) and carboxylic acids (such as 2-ethylhexanoic acid).
More than one kind of mixed solvent is preferably used.

Further, water or a known surfactant may be freely added to the above organic solvent-based developer composition. Further, an alkali agent, for example, sodium carbonate, monoethanolamine, diethanolamine, triethanolamine, sodium silicate, potassium silicate, potassium hydroxide, sodium borate and the like can be added.

To these developers, known basic dyes such as crystal violet, Victoria Pure Blue, and Astrazone Red, acid dyes, and water-soluble dyes are added, and the image area is dyed simultaneously with the development. Can be.

When developing the waterless lithographic printing plate precursor used in the present invention, an automatic developing machine such as that commercially available from Toray Industries, Inc. is used, and the plate surface is foreground with the above developing solution. After the treatment, the plate surface can be suitably developed by rubbing the plate surface with a rotating brush while showering with tap water or the like. Further, development can also be performed by spraying hot water or water vapor on the plate surface instead of the above-mentioned developer.

[0046]

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

Examples 1-4 A primer solution having the following composition was applied to a degreased aluminum plate (manufactured by Sumitomo Light Metal Co., Ltd.) having a thickness of 0.24 mm, and then heated and dried at 230 ° C. for 1 minute. 3 g / m ²
Was provided. (1) 15 parts by weight of epoxy / urea resin (2) 20 parts by weight of ethyl cellosolve (3) 20 parts by weight of ethyl cellosolve acetate (4) 45 parts by weight of dimethylformamide

Next, a photopolymerizable photosensitive solution having the following composition was applied on the primer layer, and dried by heating at 100 ° C. for 1 minute to form a photosensitive layer having a thickness of 4 g / m ² . (1) Polyurethane composed of a polyester polyol composed of adipic acid and polyethylene glycol and isophorone diisocyanate 60 parts by weight (2) N, N, N'-tetra- (2-hydroxy-3-methacryloyloxypropyl) m-xylene diamine 20 parts by weight (3) Monomers shown in Table 1 10 parts by weight (4) 4,4'-bis (dimethylamino) benzophenone 4 parts by weight (5) N-methylacridone 5 parts by weight (6) Victoria Pure Blue BOH naphthalene Sulfonate 0.5 parts by weight (7) Ethyl cellosolve 580 parts by weight

Subsequently, a silicone rubber solution having the following composition was applied on the photosensitive layer, and dried by heating at 120 ° C. for 2 minutes to form a silicone rubber layer having a thickness of 2 g / m ² . (1) Silanol dimethyl polysiloxane at both ends (weight average molecular weight 100,000) 100 parts by weight (2) Ethyltriacetoxysilane 12 parts by weight (3) Dibutyltin diacetate 0.01 part by weight (4) "Isopar E" 750 Parts by weight (isoparaffin hydrocarbons manufactured by ESSO)

The plate prepared as described above has a thickness of 12 μm.
The biaxially stretched polypropylene film having a matte surface on one side was laminated with a calender roller so that the non-matted surface was in contact with the silicone rubber layer to form a protective film, thereby obtaining a positive waterless planographic printing plate precursor.

These waterless planographic printing plate precursors were used at a temperature of 15 ° C. or 30 ° C. with a 3 kW ultra-high pressure mercury lamp (manufactured by Oak Manufacturing Co., Ltd.) at 150 lines / inch at 2% to 9%.
A gradation positive film having an 8% halftone dot and a gray scale (G / S) having an optical density difference of 0.15 by 90
After contact exposure for 2 seconds, the protective film was peeled off from the plate, and transported at an automatic developing machine (TWL-1160, manufactured by Toray Industries, Inc.) at a transfer speed of 6
Development was performed at 0 cm / min to obtain a printing plate. The printing plate obtained in this way is mounted on an offset printing press (Komori Sprint 4-color press), and high quality paper is made using "Dryocolor" ink, indigo, red, and yellow ink manufactured by Dainippon Ink and Chemicals, Inc. (6
2.5 Kg / chrysanthemum), and the printing durability of the printed image and the 15 ° C. image evaluation plate was evaluated. The results are shown in Table 2.
The GS evaluation method in the table is set to 8.0 if the silicone rubber layer remains up to the GS8 stage. With respect to decimal points and below, the area and concentration were evaluated on a 10-point scale.

Examples 5 to 8 In Example 1, a waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the photosensitive layer was changed to the following composition, and the photosensitive layer was formed. Exposure and development were performed according to the method, and image evaluation was performed. The results are shown in Table 2.

A photopolymerizable photosensitive solution having the following composition was coated on the primer layer, and dried by heating at 100 ° C. for 1 minute to form a photosensitive layer having a thickness of 4 g / m ² . (1) Polyurethane composed of polyester polyol composed of adipic acid and polyethylene glycol and isophorone diisocyanate 60 parts by weight (2) 1,2,4,6-tetra (hydroxy-3-methacryloyloxypropyloxy) -3,5-dihydroxy Hexane 20 parts by weight (3) Monomers shown in Table 1 10 parts by weight (4) 4,4'-bis (dimethylamino) benzophenone 4 parts by weight (5) N-methylacridone 5 parts by weight (6) Victoria Pure Blue BOH 0.5 parts by weight of naphthalene sulfonate (7) 580 parts by weight of ethyl cellosolve

Comparative Example 1 A waterless lithographic printing plate was prepared in the same manner as in Example 1 except that the monomer (3) in the photosensitive layer composition was changed to the following monomer, and a photosensitive layer was formed. An original plate was prepared, exposed and developed in the same manner, and the printing durability and image evaluation were performed. The results are shown in Table 2. (3) Light acrylate (“9E” manufactured by Kyoeisha Chemical Co., Ltd.)
GA ”)

Comparative Example 2 A waterless lithographic printing plate was prepared in the same manner as in Example 5 except that the monomer (3) in the photosensitive layer composition was changed to the following monomer, and a photosensitive layer was formed. An original plate was prepared, exposed and developed by the same method, and image evaluation was performed. The results are shown in Table 2. _{(3) CH 2 = C (} H) -CO-O- (CH 2 CH 2 O) 7.5- (CH 2 CH (CH 3) -O) 17 - (CH 2 CH
₂ O) _7.5 -CO-C (H) = CH ₂ ("Blemmer" 30ADC-1700B manufactured by NOF Corporation)

Example 9 A waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the silicone gum composition was changed to the following composition to form a silicone rubber layer. Exposure and development were performed to evaluate the printing durability and image quality. The results are shown in Table 2.

A silicone rubber solution having the following composition was coated on the photosensitive layer, and dried by heating at 135 ° C. for 2 minutes to provide a silicone rubber layer having a thickness of 2 g / m ² . (1) 10 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization: about 800) (2) (CH ₃ ) ₃ -Si-O- (Si (CH ₃ ) ₂ -O) _30- (SiH (CH ₃ ) -O) ₁₀ -Si- (CH ₃ ) ₃ 1.2 parts by weight (3) 0.6 parts by weight of polydimethylsiloxane (degree of polymerization: about 8000) (4) 0.2 parts by weight of olefin-chloroplatinic acid (5 parts by weight) ) Inhibitor 0.3 parts by weight (6) "Isopar E" 150 parts by weight (isoparaffinic hydrocarbon manufactured by ESSO)

Example 10 A waterless planographic printing plate precursor was prepared in the same manner as in Example 5 except that the silicone gum composition was changed to the following composition to form a silicone rubber layer. Exposure and development were performed to evaluate the printing durability and image quality. The results are shown in Table 2.

A silicone rubber solution having the following composition was coated on the photosensitive layer, and dried by heating at 135 ° C. for 2 minutes to provide a silicone rubber layer having a thickness of 2 g / m ² . (1) 10 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization: about 800) (2) (CH ₃ ) ₃ -Si-O- (Si (CH ₃ ) ₂ -O) _30- (SiH (CH ₃ ) -O) ₁₀ -Si- (CH ₃ ) ₃ 1.2 parts by weight (3) 0.6 parts by weight of polydimethylsiloxane (degree of polymerization: about 8000) (4) 0.2 parts by weight of olefin-chloroplatinic acid (5 parts by weight) ) Inhibitor 0.3 parts by weight (6) "Isopar E" 150 parts by weight (isoparaffinic hydrocarbon manufactured by ESSO)

[Table 1]

Embedded image

[Table 2] It can be seen that the plates containing the monomers of Examples 1 to 10 of the present invention in the photosensitive layer have good image reproducibility, especially at low temperatures (15 ° C.). The above effect was observed even when the addition-crosslinking reaction type silicone rubber layer was used. (Examples 9 and 10)

[0060]

According to the present invention, excellent image reproducibility and printing durability can be obtained under any conditions, such as at low temperatures, without impairing the advantages of conventional waterless planographic printing plate precursors.
We can provide waterless planographic printing plate precursors.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA04 AA12 AB04 AC01 AD01 AD03 BC65 CA01 CB22 FA15 2H096 AA13 BA05 BA20 EA02 GA03

Claims (1)

[Claims] 1. A method comprising: laminating a substrate, a photosensitive layer and a silicone rubber layer in this order;
A waterless planographic printing plate precursor comprising the three components (B) and (C). (A) at least one monomer represented by the following general formula (I): CH ₂ CC (R) —CO—O— (CH ₂ CH ₂ O) l- (CH ₂ CH (CH ₃ ) —O ) in _{m- (CH 2 CH 2 O)} n-CO-C (R) = CH 2 (I) ( wherein, R represents a hydrogen atom or a methyl group, may be different even in the same .m Is 3 to 12, l and n are 1
５5, which may be the same or different. 5 <(l + m + n) <16, and m> l + n. (B) Photopolymerization initiator (C) Polymer compound having film forming ability