JP2003287881A - Direct drawing waterless planographic printing plate precursor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a direct drawing waterless planographic printing plate precursor writable with a laser and excellent in image reproducibility and scratch resistance. <P>SOLUTION: In the direct patterning waterless planographic printing plate precursor obtained by disposing at least a photosensitive layer and a silicone rubber layer in this order on a support, the silicone rubber layer is obtained by curing reaction of a vinyl-containing polysiloxane having 0.01-0.15 wt.% concentration of vinyl groups and a silicon compound having 0.7-2.0 wt.% concentration of hydrogen atoms bonding to silicon atoms. <P>COPYRIGHT: (C)2004,JPO

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 for producing a so-called waterless lithographic printing plate, which does not require a dampening water and can be printed without using a dampening water. In particular, the present invention relates to a direct drawing type waterless planographic printing plate precursor which directly forms a printing plate by using laser light from digital image data. More specifically, it relates to a direct drawing type waterless planographic printing plate precursor in which at least a photosensitive layer and a silicone rubber layer are provided in this order on a support.

[0002]

2. Description of the Related Art The so-called direct-drawing type plate making, in which an offset printing plate is directly produced from an original without using a plate-making film, is simple without requiring skill, and quick in obtaining the printing plate in a short time. Taking advantage of rationality, which can be selected from various systems according to quality and cost, it is beginning to spread not only in the light printing industry but also in the fields of general offset printing and flexo printing. In particular, recently, new types of various direct drawing type lithographic printing plates have been developed due to rapid progress in output systems such as prepress systems, imagesetters and laser printers. These direct-drawing type lithographic printing plates are classified according to the plate making method: laser light irradiation method, thermal head writing method, partial voltage application with pin electrode, ink repellent layer or ink receptive layer by inkjet. And the like. Among them, the method of irradiating with laser light is superior to other methods in terms of resolution and plate making speed,
There are many types.

This printing plate making method of irradiating with laser light is further divided into two methods, a photon mode by photoreaction and a heat mode in which photothermal conversion is carried out to cause a thermal reaction. In particular, the heat mode method has an advantage that it can be handled in a bright room, and is a method that has recently attracted the most attention with the rapid progress of semiconductor lasers as light sources, and is said to become the mainstream in the future.

As the direct drawing type lithographic printing plate in the heat mode system, there are a direct drawing type waterless planographic printing plate which can be printed without using dampening water and a direct drawing type water-containing planographic plate which is printed using dampening water. Printed versions are being developed. The direct drawing type waterless lithographic printing plate has the advantages that the printing starts quickly and high quality printed matter is obtained, and the development system collects and reuses it with a small amount of organic solvent pretreatment and water washing. Since it is composed only by brush rubbing development, it has the advantage that very little organic waste liquid is discharged.

For example, US Pat. No. 5,378,580, JP-A-6-186750, JP-A-6-199.
No. 064, JP-A-9-244228, and US Pat. No. 5,570,636 describe a direct drawing type waterless lithographic printing plate precursor using a laser beam as a light source, a plate making method thereof and the like. Furthermore, JP-A-11-22
1977, JP-A-11-157236, JP-A-11-208135, and JP-A-11-3342.
No. 37, JP-A No. 11-348442 and the like propose a direct drawing type waterless lithographic printing plate containing a metal chelate compound and an active hydrogen group-containing compound in a heat sensitive layer. This printing plate had very good performance such as sufficient sensitivity for practical use, excellent image reproducibility, high ink resilience, and stable developability, but depending on how to handle the printing plate,
In some cases, the silicone rubber layer in the non-image area may be scratched, and there was a problem in that resistance to scratches, that is, so-called scratch resistance was not sufficient. On the other hand, proposals for improving scratch resistance have been made in JP-A-10-39497 and JP-A-12-272266, and some of them have been solved, but they are still insufficient.

Further, regarding the improvement of the silicone rubber layer of a direct drawing type waterless planographic printing plate relating to scratch resistance, JP-A-9-2399 discloses.
43, JP-A-9-258434, JP-A-9
No. 274311, Japanese Unexamined Patent Publication No. 10-186636, Japanese Unexamined Patent Publication No. 11-174666, etc. have been proposed so far, but none of them is practically sufficient.

[0007]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and is a direct drawing type waterless planographic printing which is writable by a laser and has excellent image reproducibility and scratch resistance. It is to provide the original version.

[0008]

The direct drawing type waterless lithographic printing plate precursor of the present invention which achieves the above object is a direct drawing type water in which at least a photosensitive layer and a silicone rubber layer are provided in this order on a support. None In the planographic printing plate, the silicone rubber layer
The concentration of vinyl polysiloxane having a vinyl group concentration of 0.01 to 0.15% by weight and the concentration of hydrogen atoms bonded to silicon atoms are 0.7 to
A direct drawing type waterless planographic printing plate precursor characterized by being obtained by curing reaction with 2.0% by weight of a silicon compound.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.

As the support used in the present invention, any support can be used as long as it has flexibility so that it can be set in an ordinary lithographic printing press and can withstand a load applied during printing. Is not particularly limited. For example, papers such as coated papers, metal plates such as aluminum plates, or plastic films such as polyethylene terephthalate can be cited as examples. Of these, polyethylene terephthalate, aluminum plate, or aluminum foil and other composite materials are preferable. The thickness of the substrate is usually 10 μm to 1 mm, preferably 20 μm.
It is m to 0.5 mm.

The photosensitive layer used in the present invention may be a metal thin film type or an organic compound layer containing a photothermal conversion substance.

The metal constituting the metal thin film system includes titanium, aluminum, nickel, iron, tellurium, tin, antimony, gallium, germanium, magnesium, polonium, selenium, thallium, zinc, bismuth, and oxides or sulfides of these. The thing etc. are mentioned. It is preferable to lower the melting point by mixing two or more kinds of these metal compounds to form an alloy. The thickness of the metal thin film is 1
It is preferably 000 angstroms or less, more preferably 400 angstroms or less.

When the photosensitive layer is an organic compound layer containing a photothermal conversion substance, the photothermal conversion substance may be a black pigment such as carbon black or titanium black, a phthalocyanine or naphthalocyanine pigment, carbon graphite or a diamine metal. Complex, dithiol metal complex, phenol thiol metal complex, mercaptophenol metal complex, titanium oxide, vanadium oxide, manganese oxide,
Examples thereof include metal oxides such as iron oxide, cobalt oxide and tungsten oxide, and hydroxides and sulfates of these metals. Among these, carbon black is preferable from the viewpoints of light-heat conversion rate, economy and handleability.

Further, a dye absorbing infrared rays or near infrared rays, particularly a dye, is preferably used as the photothermal conversion substance.

Particularly preferred dyes are cyanine dyes,
Phthalocyanine type, naphthalocyanine type, dithiol metal complex type, piazurhenium type, squarylium type, croconium type, azo type dispersion dye, bisazo type, bisazostilbene type, naphthoquinone type, anthraquinone type, perylene type, polymethine type, indoaniline metal Complex dyes,
Intermolecular CT system, benzothiopyran system spiropyran system,
Examples include nigrosine-based, thioindigo-based, nitroso-based, quinoline-based, and fulgide-based dyes, especially dyes. Further, among these dyes, those having a large molar absorption coefficient ε are preferably used. Specifically, ε is 1 × 1
It is preferably 0 ⁴ or more, more preferably 1 × 10 ⁵ or more. When ε is 1 × 10 ⁴ or more, the effect of improving the sensitivity is sufficiently exhibited.

These photothermal conversion substances can be used alone or in combination of two or more.

The organic layer compound layer containing the photothermal conversion substance preferably contains a binder resin.
Examples of the binder resin include known resins that dissolve or disperse the photothermal conversion substance. Examples of these are
Novolac resin, resole resin, epoxy resin, cellulose derivative, poly (meth) acrylic acid ester, polystyrene, polyurea, polyurethane, polyester, polycarbonate and the like can be used. Of these, novolac resins and resol resins have high ink receptivity to the photosensitive layer and can be preferably used.

The content of the photothermal conversion substance in the organic compound layer is preferably 0.1 to 40% by weight, more preferably 0.5 to 25% by weight based on the photosensitive layer composition. 0.
If it is 1% by weight or more, the effect of improving the sensitivity to laser light is sufficiently obtained, and if it is 40% by weight or less, the printing durability of the printing plate is less likely to decrease.

In addition to the above-mentioned compounds, the organic compound layer containing the photothermal conversion substance contains nitro group-containing compounds such as nitrocellulose, hydrazine derivatives, azo compounds, azide compounds, carbonic acid ester compounds and organic peroxides. It is also possible to add an easily decomposable compound such as, an acid generator and a radical generator.

The film thickness of the organic compound layer containing the photothermal conversion material is preferably ^{0.1~10g / m 2, 1~7g / m} 2 is more preferable. When the thickness of the photosensitive layer is 0.1 g / m ² or more, excellent sensitivity and image reproducibility are exhibited, and when it is 10 g / m ² or less, it is advantageous from an economical point of view, and also scratch resistance and printing durability. It does not reduce the sex.

The silicone rubber layer used in the present invention is
The vinyl group-containing polysiloxane having a vinyl group concentration of 0.01 to 0.15% by weight and the concentration of silicon atom-bonded hydrogen atoms are 0.1.
It is characterized by being obtained by curing reaction of a silicon compound in an amount of 7 to 2.0% by weight.

The vinyl group-containing polysiloxane used in the present invention must have a vinyl group concentration of 0.01 to 0.15% by weight. It is preferably 0.03 to 0.12% by weight. When the vinyl group concentration is 0.01% by weight or more, curability does not become a problem, and a silicone rubber layer having practical strength can be obtained. The vinyl group concentration is 0.15
If it is less than weight%, the film becomes brittle and is not easily scratched. In particular, a silicone rubber having excellent scratch resistance and image reproducibility when cured with a silicon compound containing silicon-bonded hydrogen having a concentration of hydrogen atoms bonded to silicon of 0.7 to 2.0% by weight. A layer is obtained. The vinyl group concentration is a value obtained by multiplying the number of moles of vinyl groups contained in 100 g of vinyl group-containing polysiloxane by the formula weight 27. The vinyl group concentration can be measured by a titration method using iodine monochloride or nuclear magnetic resonance spectroscopy.

The vinyl group-containing polysiloxane may have a chain structure, a cyclic structure, or a branched structure, but a chain structure is preferable. The remaining substituents other than the vinyl group are preferably methyl groups in order to obtain good printing ink resilience. Molecular chain both ends dimethylvinylsiloxy group blocked polydimethylsiloxane, molecular chain both terminals trimethylsiloxy group blocked dimethylsiloxane / methylvinylsiloxane copolymer, molecular chain both terminals dimethylvinylsiloxy group blocked dimethylsiloxane / methylvinylsiloxane copolymer Can be mentioned. The weight average molecular weight is preferably 5,000 to 1,000,000, more preferably 50,000 to 600,000.
When the weight average molecular weight is 5,000 or more, the strength as a silicone rubber layer can be obtained, and the resilience of printing ink does not become a problem. Further, the weight average molecular weight is 100
If it is 50,000 or less, there will be no difficulty in production, and there will be no difficulty during coating work.

The silicon compound used in the present invention having a silicon atom-bonded hydrogen atom concentration of 0.7 to 2.0% by weight is a component acting as a crosslinking agent. The concentration of silicon atom-bonded hydrogen atoms can be measured by nuclear magnetic resonance spectroscopy or the like. When the concentration of silicon atom-bonded hydrogen atoms is 0.7% by weight or more, a silicone rubber layer having excellent scratch resistance is obtained, and when the concentration is 2.0% by weight or less, decomposition of silicon atom-bonded hydrogen atoms such as decomposition of the silicon compound itself. Stability is never an issue. For example, an organohydrogenpolysiloxane and an organic polymer having a diorganohydrogensilyl group can be mentioned, and an organohydrogensiloxane is preferable. Organohydrogen has a linear, cyclic, branched or reticulated molecular structure, and has a trimethylsiloxy group-blocked polymethylhydrogensiloxane at both molecular chain ends, and a dimethylsiloxymethylmethylhydrogensiloxane having trimethylsiloxy group at both molecular chain ends. Copolymer, dimethylsiloxy group-methylhydrogensiloxane-methylphenylsiloxane copolymer, dimethylsiloxy group-capped at both ends of the molecular chain, dimethylhydrogensiloxy group-capped dimethylpolysiloxane, dimethylhydrogenoxy group at both ends of the molecular chain Blocked dimethyl siloxane / methyl phenyl siloxane copolymer, molecular chain both ends dimethyl hydrogen siloxy group blocked methyl phenyl polysiloxane, formula: R3SiO1 / 2
An organopolysiloxane copolymer comprising a siloxane unit represented by the formula: R2HSiO1 / 2 and a siloxane unit represented by the formula: SiO4 / 2, a formula:
R2 HSiO1 / 2 siloxane unit and formula: SiO4 /
An organopolysiloxane copolymer comprising a siloxane unit represented by the formula 2, an organosiloxane comprising a siloxane unit represented by the formula: RHSiO2 / 2 and a siloxane unit represented by the formula: RSiO3 / 2, or a siloxane unit represented by the formula: HSiO3 / 2. Examples include polysiloxane copolymers, and mixtures of two or more of these organopolysiloxanes. In the above formula, R is a monovalent hydrocarbon group other than an alkenyl group,
Alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group and heptyl group; aryl groups such as phenyl group, tolyl group, xylyl group and naphthyl group; aralkyl groups such as benzyl group and phenethyl group Examples thereof include halogenated alkyl groups such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group and the like. The viscosity of the organohydrogenpolysiloxane is not limited, but the viscosity at 25 ° C. is 1 to 100,000.
0 cSt is preferable, and especially 1 to 10,000
It is preferably 0 cSt.

Examples of the organic polymer having a diorganohydrogensilyl group include dimethylhydrogensilyl group-containing acrylic monomers such as dimethylhydrogensilyl (meth) actrate and dimethylhydrogensilylpropyl (meth) acrylate, and ( Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, ethylhexyl (meth) acrylate, lauryl (meth) acrylate, styrene, α-methylstyrene, maleic acid, vinyl acetate, allyl acetate, etc. An oligomer obtained by copolymerizing the above monomer is used.

The concentration of silicon atom-bonded hydrogen atoms is 0.7 to
The amount of the silicon compound added, which is 2.0% by weight, is 1 to 30 parts by weight, preferably 1.5 to 10 parts by weight, relative to 100 parts by weight of the vinyl group-containing polysiloxane having a vinyl group concentration of 0.01 to 0.15% by weight. 15 parts by weight. When the addition amount of the silicon compound is 1 part by weight or more, curing of the silicone rubber layer is insufficient and the film strength is not insufficient, and the image reproducibility and scratch resistance are not deteriorated. On the other hand, if the addition amount of the silicon compound is 30 parts by weight or less, the silicon atom-bonded hydrogen atoms remain, and the printing ink repulsion, image reproducibility and scratch resistance are not affected.

To cure the vinyl group-containing polysiloxane having a vinyl group concentration of 0.01 to 0.15% by weight and the silicon compound having a concentration of silicon atom-bonded hydrogen atoms of 0.7 to 2.0% by weight. Usually, an addition reaction catalyst is used. The addition reaction catalyst can be arbitrarily selected from known catalysts, but is preferably a platinum-based catalyst, and one or a mixture of two or more selected from platinum group metals and platinum group-based metal compounds is used. Examples of the platinum group metal include simple substance of platinum (for example, platinum black), simple substance of palladium (for example, palladium black), simple substance of rhodium, and the like. As the platinum group compound, chloroplatinic acid, platinum-olefin complex, platinum-alcohol complex, platinum-ketone complex, platinum-vinylsiloxane complex, tetrakis (triphenylphosphine) platinum, tetrakis (triphenylphosphine) palladium, etc. Is exemplified. Among these, chloroplatinic acid or a platinum-olefin complex dissolved in an alcohol solvent, a ketone solvent, an ether solvent, a hydrocarbon solvent, or the like is particularly preferable. The addition amount of the addition reaction catalyst is 0.01 to 20% by weight, preferably 0.1 to 10% by weight in the silicone rubber composition. When the amount of the catalyst added is 0.01% by weight or more, the silicone rubber layer will be sufficiently cured, and there will be no problem in the adhesion to the photosensitive layer. On the other hand, when it is 20% by weight or less, the pot life of the silicone rubber layer solution is not adversely affected. In terms of platinum and other metals, 10-100
It is preferably 0 ppm, preferably 100 to 500 ppm.

In addition to the above composition, the silicone rubber layer used in the present invention has a hydrolyzable functional group-containing silane or siloxane for the purpose of enhancing the film strength of the silicone rubber layer, and for improving the adhesiveness. A known silane coupling agent, titanate coupling agent, aluminum coupling agent or the like may be contained. As the silane coupling agent, alkoxysilanes, acetoxysilanes, ketoximinesilanes and the like are preferable, and those having a vinyl group and ketoximinesilanes are particularly preferable.

When ketoximine silanes are used,
It is particularly preferable because it not only functions as an adhesiveness-imparting agent, but also functions as a reaction inhibitor because it is a nitrogen-containing compound. The amount of such a compound added is preferably 0.5 to 20 parts by weight, and more preferably 100 parts by weight of the vinyl group-containing polysiloxane having a vinyl group concentration of 0.01 to 0.15% by weight. 1 to 5 parts by weight.
When the amount is more than 0.5 part by weight, the effect of exhibiting adhesiveness is exerted, while when the amount is 20 parts by weight or less, sufficient repulsion of the printing ink can be exhibited.

The silicone rubber layer used in the present invention has a viscosity increase during storage of a coating solution of the silicone rubber layer composition for coating the silicone rubber layer and a rapid increase of the silicone rubber layer during coating. A curing retarder can be added for the purpose of preventing curing. As a curing retarder, generally known acetylene alcohol, maleic acid ester, silylation product of acetylene alcohol, silylation product of maleic acid, triallyl isocyanurate,
It can be arbitrarily selected from vinyl siloxane and the like. The preferred amount of the curing retarder added is a vinyl group concentration of 0.
The vinyl group content of 01 to 0.15% by weight is 0.001 to 10% by weight, and more preferably 0.01 to 5% by weight, based on 100 parts by weight of the polysiloxane.

Further, for the purpose of improving the strength of the silicone rubber layer used in the present invention, an inorganic filler such as silica, titanium oxide or aluminum oxide may be added.

The thickness of the silicone rubber layer used in the present invention is preferably 0.5 to 20 g / m ² , more preferably 1 to 4 g / m ² . When the film thickness is 0.5 g / m ² or more, the ink repulsion, scratch resistance and printing durability of the printing plate are not deteriorated, and when the film thickness is 20 g / m ² or less, it is not only advantageous from the economical point of view. There is no problem that the developability and the ink mileage deteriorate.

The photosensitive layer composition and the silicone rubber layer composition described above are dissolved in a suitable solvent to prepare a solution, which is then applied to a support by means of various coating devices such as a wire bar, a spinner and a roll coater. After coating on the surface, it can be dried to form a photosensitive layer and a silicone rubber layer, respectively. Examples of the coating solvent for the photosensitive layer include ketones such as methyl ethyl ketone and cyclohexanone, esters such as butyl acetate, amyl acetate and ethyl propionate, and hydrocarbons such as toluene, xylene, monochlorobenzene, carbon tetrachloride, trichloroethylene and trichloroethane. And halogenated hydrocarbons, ethers such as methyl cellosolve, ethyl cellosolve, and tetrahydrofuran,
Further, a conventional one such as propylene glycol monomethyl ether acetate or dimethylformamide can be used, and as a coating solvent for the silicone rubber layer, n is used.
-Hexane, cyclohexane, toluene, xylene, petroleum ether, aliphatic hydrocarbon solvent Exxon Chemical Co., Ltd.
Production: Isopars E, H, G and mixed solvents of these solvents and the above-mentioned photosensitive layer coating solvent can be used.

The waterless planographic printing plate precursor of the present invention has various releasable plastic sheets such as polypropylene sheet, polyethylene sheet, release treated polyethylene terephthalate and release treated paper for the purpose of protecting the silicone rubber layer if necessary. A metal sheet of aluminum, iron, copper or the like may be laminated on the silicone rubber layer.

A direct drawing type waterless planographic original plate having at least a photosensitive layer and a silicone rubber layer on a support is imagewise exposed with a laser beam after peeling off the protective film. The laser light source used in the plate-making exposure step has an emission wavelength range of 300 nm to 1
A laser having a wavelength in the range of 500 nm is used, and among these, a semiconductor laser or a YAG laser having an emission wavelength region near the near infrared region is preferably used. Specifically, from the viewpoint of handling the plate material in a bright room,
Laser light having a wavelength of 0 nm, 830 nm, 1064 nm and its vicinity is preferably used for plate making.

The original plate after the laser irradiation is developed by a rubbing treatment in the presence or absence of water or an organic solvent. The rubbing treatment is performed by wiping the plate surface with a non-woven fabric impregnated with a developing solution, absorbent cotton, cloth, sponge or the like, or by pre-treating the plate surface with the following developing solution and rubbing with a rotating brush while showering tap water or the like. be able to. The developer used in the case of performing the development treatment, for example, water or water with a surfactant added, further water with a polar solvent such as an alcohol, a ketone, an ester, or a carboxylic acid, A solvent in which at least one kind of polar solvent is added to a solvent composed of at least one kind of aliphatic hydrocarbons and aromatic hydrocarbons, or a polar solvent is used. Further, a known surfactant may be freely added to the above-mentioned developer composition.

In the original plate after development, the image area where the silicone rubber layer is removed in order to confirm image formation can be dyed with a dyeing solution so that it can be detected. As the dyeing liquid, one or more selected from water-soluble disperse dyes, acid dyes and basic dyes can be used alone or in a mixture of two or more of water, alcohols, ketones and ethers. What is dissolved or dispersed is used. It is also effective to add carboxylic acids, amines, surfactants, dyeing assistants, defoaming agents, etc. in order to improve dyeability. The original plate dyed with the dyeing solution is preferably washed with water and then dried.

[0038]

EXAMPLES The present invention will now be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

Example 1 (Support) Degreased aluminum for printing plates having a thickness of 0.225 mm (material 1100-H18, manufactured by Sumitomo Light Metal Industries, Ltd.) (Photosensitive layer) A coating solution containing the following components It was coated on the above support, heated (150 ° C., 80 seconds) and dried to form a photosensitive layer having a dry film thickness of 1.5 g / m ² .

"YKR-2900" (infrared absorbing dye, manufactured by Yamamoto Kasei Co., Ltd.): 10 parts by weight "Narsem titanium" (titanium di-n-butoxide side bis (2,4-pentanedionate, Nippon Kagaku Sangyo Co., Ltd.)
(Metal chelate compound): 15 parts by weight "Sumilite Resin" PR54652 (phenol novolac resin, manufactured by Sumitomo Dures Co., Ltd.): 60 parts by weight "Samprene" T-1331D (polyurethane resin)
Sanyo Chemical Industry Co., Ltd.): 10 parts by weight 3-glycidoxypropyltrimethoxysilane: 5 parts by weight Tetrahydrofuran: 800 parts by weight Dimethylformamide: 100 parts by weight (silicone rubber layer) Coating consisting of the following components The solution was applied onto the photosensitive layer, heated (125 ° C., 80 seconds), and dried to form a silicone rubber layer having a dry film thickness of 2.0 g / m ² to obtain a direct drawing type waterless planographic printing plate precursor. It was

· Vinyl group-containing polysiloxane "DMS-"
V52 "(manufactured by GELEST Inc., polydimethylsiloxane capped with dimethylvinylsiloxy groups at both molecular chain ends,
Vinyl group concentration 0.07% by weight, weight average molecular weight 150,
000, viscosity 165,000 cSt, polymer A) in the table: 100 parts by weight-silicon compound having a silicon atom-bonded hydrogen atom "SH
1107 "(Toray Dow Corning Silicone Co., Ltd.)
Manufactured by Polymethylhydrogensiloxane endblocked with trimethylsiloxy groups at both molecular chain ends, viscosity 20 cSt, silicon atom-bonded hydrogen atom concentration (hereinafter, H concentration) 1.6% by weight, compound G in the table): 3.0 parts by weight. Vinyltri (methylethylketoximine) silane: 3
Parts by weight Platinum catalyst "SRX-212" (manufactured by Toray Dow Corning Silicone Co., Ltd.): 5 parts by weight "ISOPAR" E (manufactured by Esso Chemical Co., Ltd.): 770 parts by weight Toluene: 260 parts by weight 6 μm on the surface of the silicone rubber layer obtained as
Of polypropylene film was laminated.

(Scratch resistance test) The obtained waterless planographic printing plate precursor was mounted on a plate making machine GX-3600 (manufactured by Toray Industries, Inc.) and exposed at a irradiation energy of 150 mJ / cm 2 using a semiconductor laser having a wavelength of 830 nm. went.

Subsequently, the automatic developing device TWL-860KII
(Manufactured by Toray Industries, Inc.), pretreatment liquid "NP-1"
(Toray Co., Ltd.) after pretreatment for 30 seconds, brush development under washing with water, peel off the exposed silicone rubber layer,
A waterless planographic printing plate was obtained. For the laser non-irradiated area (non-image area) of this printing plate, a continuous weighted scratch strength tester (HEIDON-18) manufactured by Shinto Chemical Co., Ltd. Then, the printing plate was moved at 30 cm / min while being continuously loaded from no load to 100 g to scratch it. Print using this waterless planographic printing plate,
The minimum load at which scratches were observed on the printed matter was taken as the scratch resistance of the plate, and the scratch resistance was evaluated. As a result, the scratch resistance was 55 g.
And was good. It indicates that the higher the scratch resistance, the higher the film strength of the silicone rubber layer, the less the occurrence of scratches due to paper dust during printing, and the more resistant to scratches. When the scratch resistance is 15 g or less, scratches are likely to occur due to dust or agglomerates of paper powder mixed in during printing, which is a problem in practical use.

(Scratch resistance test) A non-laser-irradiated portion (non-image area) (6 cm × 6 cm) of a waterless planographic printing plate obtained in the same manner as in the scratch resistance test was used by Daiei Kagaku Seiki Seisakusho Ltd. Attached to a friction-fastness tester, manufactured by Gakushin-shoku type dyeing machine, and brushed pad (made of Cambo Create Co., Ltd.) with a length of about 5 mm for hair (polyester, diameter of about 20 μm).
Using “Caperon” NS5100) (2 cm × 3 cm), rubbing was repeated 150 times under a load of 100 g. Printing was performed using this waterless planographic printing plate, the appearance of scratches was observed on the printed matter, and the results were judged according to the following criteria. As a result, neither scratches nor scratches were observed at all, and the evaluation score was 5. The higher this evaluation value is, the less scratches are likely to occur, and when the evaluation value is 2 points or less, the print surface may be damaged due to scratches on the plate surface due to accidental rubbing that occurs during handling or development. is there. 5 points: No scratches or scratches are observed. 4 points: Scratches and scratches are slightly observed. 3 points: scratches and scratches are observed. 2 points: An almost circular scratch is observed in the center of the sample. 1 point: A scratch is observed on almost the entire surface.

(Image reproducibility) The obtained waterless planographic printing plate precursor was mounted on a plate making machine GX-3600 (manufactured by Toray Industries, Inc.) and irradiated with a semiconductor laser having a wavelength of 830 nm at an irradiation energy of 150 mJ / cm ² . -99% halftone dot exposure was performed.

Subsequently, the automatic developing device TWL-860KII
(Manufactured by Toray Industries, Inc.), pretreatment liquid "NP-1"
(Toray Co., Ltd.) after pretreatment for 30 seconds, brush development under washing with water, peel off the exposed silicone rubber layer,
A waterless planographic printing plate was obtained.

The obtained printing plate was used as a sheet-fed offset printing machine "Sprint 25" (manufactured by Komori Corporation).
Waterless lithographic ink "Dryo Color NS
I ", indigo (manufactured by Dainippon Ink and Chemicals, Inc.) was used to print on high-quality paper (62.5 kg / chrysanthemum), and the image reproducibility as a print was evaluated. The points were reproduced and judged to be good.
Good reproduction of halftone dots up to 99%, somewhat good reproduction of halftone dots of 5 to 95%, 5% or 95%
Those in which the halftone dots were not reproduced were judged to be defective.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

Example 2 In Example 1, a silicon compound having a silicon atom-bonded hydrogen atom was used as “HQM-10”.
5 "(manufactured by GELEST Inc., an organopolysiloxane copolymer having a siloxane unit represented by the formula: R3SiO1 / 2, a siloxane unit represented by the formula: R2HSio1 / 2 and a siloxane unit represented by the formula: SiO4 / 2, and a viscosity 5
cSt, H concentration 0.84% by weight, compound H in the table) 4.
A printing plate precursor was prepared and evaluated in the same manner except that the amount was changed to 0 part by weight. The obtained results are shown in Table 1.

Example 3 In Example 1, the silicon compound having a silicon atom-bonded hydrogen atom was designated as “RD-1”.
(Manufactured by Toray Dow Corning Silicone Co., Ltd., a dimethylsiloxane blockered with trimethylsiloxy groups at both molecular chain ends)
Methyl hydrogen siloxane copolymer, viscosity 5cS
t, H concentration 0.75% by weight, except that the compound I) in the table was changed to 4.0 parts by weight, a printing plate precursor was prepared in exactly the same manner,
It evaluated similarly. The obtained results are shown in Table 1.

[Example 4] In Example 1, the vinyl group-containing polysiloxane was replaced with a polydimethylsiloxane having a vinyl group concentration of 0.035% by weight and having a dimethylvinylsiloxy group at both ends of the molecular chain (Toray Dow Corning Silicone Co., Ltd.). Made, weight average molecular weight 230,000, viscosity 54
50,000 cSt, changed to polymer B) in the table, and changed the silicon compound having a silicon atom-bonded hydrogen atom to "RD-
A printing plate precursor was prepared and evaluated in exactly the same manner except that the amount of 1 "(Compound I in the table) was changed to 3.0 parts by weight. The obtained results are shown in Table 1.

[Example 5] In Example 1, the vinyl group-containing polysiloxane was replaced with a polydimethylsiloxane having a vinyl group concentration of 0.11% by weight and having dimethylvinylsiloxy groups at both ends of the molecular chain (Toray Dow Corning Silicone Co., Ltd.).
Made, weight average molecular weight 100,000, viscosity 42,000
Printing plate precursor in exactly the same manner except that cSt was changed to Polymer C) in the table and the silicon compound having a silicon atom-bonded hydrogen atom was changed to 6.0 parts by weight of "RD-1" (Compound I in the table). Was prepared and evaluated in the same manner. The obtained results are shown in Table 1.

[Example 6] In Example 1, the vinyl group-containing polysiloxane was used as a vinyl group-containing polysiloxane having a vinyl group concentration of 0.06% by weight and a dimethylsiloxy-methylvinylsiloxane copolymer capped with trimethylsiloxy groups at both ends (Toray Dow Corning).・ Silicone Co., Ltd., weight average molecular weight 500,
000, 1,000,000 cSt or more, except that the polymer D) in the table was changed, a printing plate precursor was prepared and evaluated in the same manner. The obtained results are shown in Table 1.

Example 7 In Example 1, the vinyl group-containing polysiloxane was used as the vinyl group-containing polysiloxane having a vinyl group concentration of 0.06% by weight. A printing plate precursor was prepared in exactly the same manner except that it was changed to D) and the silicon compound having a silicon atom-bonded hydrogen atom was changed to 4.0 parts by weight of "RD-1" (Compound I in the table). evaluated. The obtained results are shown in Table 1.

[Example 8] In Example 1, the vinyl group-containing polysiloxane was used as a polydimethylsiloxane having a vinyl group concentration of 0.018% by weight and having both ends of the molecular chain blocked with dimethylvinylsiloxy groups (Toray Dow Corning Silicone Co., Ltd.). Made, weight average molecular weight 400,000, 1 million c
Printing was carried out in exactly the same manner except that the amount of St or above was changed to polymer E) in the table and the addition amount of the silicon compound “SH1107” (compound G in the table) having a silicon atom-bonded hydrogen atom was changed to 5.0 parts by weight. An original plate was prepared and evaluated in the same manner. The obtained results are shown in Table 1.

Comparative Example 1 (Support) Thickness 0.225 m
m degreased aluminum for printing plate (material 1100-H
18, manufactured by Sumitomo Light Metal Industries, Ltd.

(Photosensitive layer) A coating solution comprising the following components was coated on the above support and heated (150 ° C., 80 seconds),
After drying, a photosensitive layer having a dry film thickness of 1.5 g / m ² was provided.

"YKR-2900" (infrared absorbing dye, manufactured by Yamamoto Kasei Co., Ltd.): 10 parts by weight "Narsem titanium" (titanium di-n-butoxide side bis (2,4-pentanedionate, Nippon Kagaku Sangyo Co., Ltd.)
(Metal chelate compound): 15 parts by weight "Sumilite Resin" PR54652 (phenol novolac resin, manufactured by Sumitomo Dures Co., Ltd.): 60 parts by weight "Samprene" T-1331D (polyurethane resin)
Sanyo Kasei Co., Ltd .: 10 parts by weight-3-glycidoxypropyltrimethoxysilane: 5 parts by weight Tetrahydrofuran: 800 parts by weight Dimethylformamide: 100 parts by weight

(Silicone rubber layer) A coating solution comprising the following components was coated on the photosensitive layer and heated (125 ° C., 8 ° C.).
After drying for 0 second), a silicone rubber layer having a dry film thickness of 2.0 g / m ² was provided to obtain a direct drawing type waterless planographic printing plate precursor.

· Vinyl group-containing polysiloxane "DMS-"
V52 "(manufactured by GELEST Inc., polydimethylsiloxane capped with dimethylvinylsiloxy groups at both molecular chain ends,
Vinyl group concentration 0.07% by weight, weight average molecular weight 150,
000, viscosity 165,000 cSt, polymer A) in the table: 100 parts by weight-silicon compound having a silicon atom-bonded hydrogen atom "HM"
S-501 "(manufactured by GELEST Inc., dimethylsiloxy-methylhydrogensiloxane copolymer with trimethylsiloxy groups blocked at both molecular chain ends, viscosity 12 cS
t, H concentration 0.69% by weight, compound J) in the table: 5.0
Parts by weight vinyltri (methylethylketoximine) silane: 3
Parts by weight Platinum catalyst "SRX-212" (manufactured by Toray Dow Corning Silicone Co., Ltd.): 5 parts by weight "ISOPAR" E (manufactured by Esso Chemical Co., Ltd.): 770 parts by weight Toluene: 260 parts by weight 6 μm on the surface of the silicone rubber layer obtained as
Of polypropylene film was laminated.

The obtained printing plate precursor was evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.

[Comparative Example 2] In Example 5, a silicon compound having a silicon atom-bonded hydrogen atom was used as "HMS-50".
A printing plate precursor was prepared and evaluated in the same manner except that the addition amount to 1 ″ (Compound J in the table) was changed to 7.0 parts by weight. The obtained results are shown in Table 1.

[Comparative Example 3] In Example 6, a silicon compound having a silicon atom-bonded hydrogen atom was used as "HMS-50".
A printing plate precursor was prepared and evaluated in the same manner except that the addition amount to 1 ″ (Compound J in the table) was changed to 5.0 parts by weight. The obtained results are shown in Table 1.

[Comparative Example 4] In Example 8, a silicon compound having a silicon atom-bonded hydrogen atom was used as "HMS-50".
A printing plate precursor was prepared and evaluated in the same manner except that the addition amount to 1 ″ (Compound J in the table) was changed to 5.0 parts by weight. The obtained results are shown in Table 1.

[Comparative Example 5] In Example 1, the vinyl group-containing polysiloxane was replaced by a polydimethylsiloxane having a vinyl group concentration of 0.155% by weight and having dimethylvinylsiloxy groups at both ends of the molecular chain (Toray Dow Corning Silicone Co., Ltd.). Made, weight average molecular weight 40,000, viscosity 10,0
00cSt, changed to polymer F) in the table, silicon compound "SH1107" having a silicon atom-bonded hydrogen atom
A printing plate precursor was prepared and evaluated in the same manner except that the addition amount of (Compound G in the table) was changed to 7.0 parts by weight. The obtained results are shown in Table 1.

[0068]

According to the present invention, a direct drawing type waterless planographic printing plate precursor having excellent image reproducibility and scratch resistance can be obtained.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H025 AA04 AA13 AB04 AC08 AD01                       AD03 CC20 DA37 FA17                 2H096 AA13 BA16 EA04 GA08

Claims (2)

[Claims] 1. A direct drawing type waterless lithographic printing plate precursor comprising at least a photosensitive layer and a silicone rubber layer provided in this order on a support, wherein the silicone rubber layer has a vinyl group concentration of 0.01 to 0.15. A direct drawing type water, which is obtained by a curing reaction of a vinyl group-containing polysiloxane of weight% and a silicon compound having a concentration of silicon atom-bonded hydrogen atoms of 0.7 to 2.0% by weight. None Original planographic printing plate. 2. A direct drawing type waterless planographic printing original plate according to claim 1, wherein the photosensitive layer contains a compound which converts laser light into heat.