JPH09131976A - Direct drawing type waterless lithographic printing original plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve scumming properties and sensitivity by forming a silicone rubber layer on a lower layer of an ink acceptive heat-sensitive layer and using a metal film of low melting point as the ink acceptive heat-sensitive layer. SOLUTION: When an ink acceptive heat-sensitive layer is formed on a silicone rubber layer provided on a base and a direct drawing type waterless lithographic printing original plate is constituted, the ink acceptive heat-sensitive layer is formed by a metal film. the ink acceptive heat-sensitive layer is a metal film having a melting point of 930K or lower. As for the metal, anyone of tellurium, tin, antimony, gallium, magnesium, polonium, selenium, tarium, zinc and bismuth is used. The scumming properties and sensitivity can be improved by the arrangement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterless planographic printing plate precursor which can be printed without using dampening water, and more particularly to a direct drawing type waterless planographic printing plate precursor which can be directly made by laser light. Things.

[0002]

2. Description of the Related Art Direct plate making, in which an offset printing plate is produced directly from an original without using a plate making film, is simple, does not require skill, is quick in obtaining a printing plate in a short time, Utilizing features such as rationality that can be selected according to quality and cost from the system,
In addition to the light printing industry, it has begun to enter the general offset printing and gravure printing fields.

In recent years, new types of various lithographic printing materials have been developed in recent years due to rapid advances in output systems such as prepress systems, imagesetters, and laser printers.

[0004] These lithographic printing plates can be classified according to plate making methods: a method of irradiating a laser beam, a method of writing with a thermal head, a method of partially applying a voltage with a pin electrode,
A method of forming an ink repellent layer or an ink deposited layer by ink jetting, and the like can be given.

[0005] Above all, the method using laser light is superior to other methods in resolution and plate making speed.
There are many types.

[0006] The lithographic printing plate using the laser light is further classified into two types, a photon mode by a photoreaction and a heat mode by which photothermal conversion is performed to cause a thermal reaction.

As the photon mode type, (1) a high sensitivity PS plate using a photopolymer (2) an electrophotographic lithographic plate using an organic photoconductor or zinc oxide (3) a silver salt lithographic plate (4) a silver salt composite System lithography (5) Direct drawing master, etc., and the heat mode type includes (6) Thermal destruction system lithography.

[0008]

However, (1)
The method uses an argon ion laser as the laser light source, which makes the equipment large, and the printing plate uses high-sensitivity photopolymer. There is a drawback that the property is easily reduced.

The electrophotographic lithographic method (2) has an advantage that it can be handled in a bright room, but since the dark decay becomes large within 2 to 5 minutes after charging of the photosensitive layer, the exposure and development process is performed in a short time after charging. Therefore, it is difficult to output a large format with high resolution.

In the silver salt method (3), printing plates corresponding to lasers of various wavelengths have been developed. However, there is a problem that silver waste liquid comes out, and since the sensitivity is high, care must be taken when handling. There is also a problem that requires.

(4) The silver-salt composite lithographic plate is provided with a high-sensitivity silver halide emulsion layer on a photosensitive layer, exposing the upper silver halide emulsion layer with an argon ion laser, developing the resultant, and further using the mask as a mask for further ultraviolet irradiation. Exposure and development. However, since this printing plate has two exposure and development steps, there is a problem that the processing of the printing plate becomes complicated.

The direct drawing master (5) does not directly write on a printing plate with a laser, but transfers a toner image formed by a laser printer onto a printing plate as an ink-coated portion. However, the resolution of the printing plate is inferior to other methods.

For the above photon mode type,
The thermal destruction method of (6) has an advantage that it can be handled in a bright room, and its usefulness has recently been reviewed due to the rapid progress of the semiconductor laser that serves as a light source.

For example, JP-A-6-199064, JP-A-7-164773, USP5339737, US
P5353705, EP0580393, JP-A-6
-55723, EP0573091, USP537
Japanese Patent No. 8580 describes a direct drawing type waterless planographic printing plate precursor using a laser beam as a light source.

The ink-receptive heat-sensitive layer of the thermal destruction printing plate precursor uses carbon black as the laser light absorbing compound and nitrocellulose as the thermal decomposition compound. The carbon black absorbs the laser light to be converted into heat energy, and the heat destroys the ink-receptive heat-sensitive layer.

Finally, by removing this portion by development, the silicone rubber layer on the surface is peeled off at the same time to form an ink inking portion.

However, this printing plate has a problem that the sensitivity of the printing plate is low because the absorptance of laser light is not sufficient.

The cause of this is that the primary particle diameter of the carbon black used is not appropriate. That is, the primary particle diameters of the carbon blacks used in the above patents are all 30 μm or more, and it cannot be said that the light of the used semiconductor laser (wavelength near 800 nm) is always absorbed efficiently. This is because the optical density as a printing plate, which is one measure of the absorption efficiency of laser light, does not reach the maximum with the above particle size. That is, the optical density becomes maximum when the particle diameter is around 20 μm, and when it is larger than 30 μm, the blackness decreases. This is because the reflection of light on the surface increases.

Further, even if the particle diameter is smaller than 15 μm, the optical density is lowered. This is because the carbon black itself tends to become transparent as the particles become smaller and the dispersibility of the particles decreases.

Further, since the carbon black of the above patent has a high oil absorption, that is, has a high structure structure, the particles agglomerate with each other, and the viscosity of the ink-receptive heat-sensitive layer solution increases. There are problems that handling is inconvenient and the coating film is not uniform.

Further, in particular, JP-A-6-55523, EP
In 0573991 and US Pat. No. 5,378,580, since an Nd-YAG laser is used as a light source, there is another problem that the exposure apparatus becomes quite large.

Further, US Pat. No. 5,379,698 describes a direct drawing type waterless planographic printing plate using a metal thin film as an ink-receptive heat-sensitive layer.

This is one in which a silicone rubber layer which is an ink repellent layer is formed on a metal thin film, and the metal used is a metal having a relatively high melting point such as titanium, aluminum, iron, nickel or chromium. Therefore, there is a problem that the sensitivity of the printing plate is low.

In addition, since this printing plate material has a very thin ink-receptive heat-sensitive layer, a very sharp image can be obtained, which is advantageous in terms of the resolution of the printing plate, but the temperature of the plate surface during printing is high. When the temperature rises, there is a problem that the ink adheres to the silicone rubber layer which is the non-image area, and as a result, the printed matter is stained (ground stain).

The cause is that the thickness of the silicone rubber layer is thin.

Therefore, in order to improve the stain resistance, it is necessary to increase the thickness of the silicone rubber layer.
When the film thickness is increased, there arises a problem that developability is deteriorated.

Further, since the cells in the image area are deep, there is a problem that too much ink is deposited and the ink consumption tends to increase.

This problem is a problem common to waterless planographic printing plates of the silicone rubber upper layer type, and as a method for solving this problem, in a conventional waterless planographic printing plate, a silicone rubber layer is provided below the photosensitive layer. A waterless lithographic printing plate of silicone rubber lower layer type is described in JP-B-56-14976.

This is not a direct drawing type but an ordinary waterless planographic printing plate, but it is preferable to laminate a photosensitive layer on a silicone rubber layer because the silicone rubber layer easily repels many liquids. It is extremely difficult to apply to.

Further, even if the coating can be satisfactorily applied, there is a problem that the surface layer is easily peeled off at the time of printing due to poor adhesion to the silicone rubber layer, resulting in poor printing durability.

This was due to the difficulty of forming a chemical bond between the silicone rubber layer and the photosensitive layer.

In order to improve the drawbacks of the prior art, the present invention provides a silicone rubber layer under the ink-receptive heat-sensitive layer, uses a thin film of a metal having a low melting point as the ink-receptive heat-sensitive layer, and further comprises two layers. By providing a layer of a silane coupling agent between them, it is possible to improve the adhesion to the silicone rubber layer, and as a result, to provide a direct drawing type waterless planographic printing plate precursor with improved background stain resistance and sensitivity. To aim.

[0033]

To achieve the above object, the present invention comprises the following constitution.

1. In a direct drawing type waterless lithographic printing plate precursor comprising a substrate, a silicone rubber layer provided on the substrate, and an ink receiving heat sensitive layer provided on the silicone rubber layer, the ink receiving heat sensitive layer is a thin metal film. A direct drawing type waterless planographic printing plate precursor characterized by being present.

2. 1. The direct drawing type waterless planographic printing plate precursor as described in 1 above, wherein the ink-receptive heat-sensitive layer is a thin metal film having a melting point of 930 (K) or less.

3. In the above 1, the metal is tellurium, tin,
A direct drawing type waterless planographic printing plate precursor characterized by being any one of antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth.

4. 1. The direct drawing type waterless planographic printing plate precursor as described in 1 above, wherein the metal is an alloy composed of a combination of any two kinds of tellurium, tin, antimony, gallium, bismuth and zinc.

5. 1. The direct drawing type waterless lithographic printing plate precursor as described in 1 above, wherein the metal is an alloy comprising a combination of any three kinds of tellurium, tin, antimony, gallium, bismuth and zinc.

6. 1. The direct drawing type waterless lithographic printing plate precursor as described in 1 above, wherein the thickness of the ink-receptive heat-sensitive layer is 50 to 10,000 angstroms.

7. 1. The direct drawing type waterless lithographic printing plate precursor as described in 1 above, wherein the ink-receptive heat-sensitive layer has an optical density of 0.6 to 2.5.

8. 1. A waterless lithographic printing plate precursor for direct drawing, which is characterized in that a silane coupling agent layer is provided between the silicone rubber layer and the ink-receptive heat-sensitive layer in the above 1.

9. 1. A waterless planographic printing plate precursor for direct drawing, which is characterized in that a silane coupling agent layer is provided between the substrate and the silicone rubber layer in the above 1.

10. 1. The direct drawing type waterless lithographic printing plate precursor as described in 1 above, wherein the silicone rubber layer contains a silane coupling agent.

11. Direct drawing type waterless, characterized in that a substrate having a silicone rubber layer surface on one side and a film having an ink-receptive heat-sensitive layer on one side are laminated so that the silicone rubber layer surface side and the ink-receptive heat-sensitive layer surface side are in contact. Method for manufacturing lithographic printing plate precursor.

12. 11. The method for producing a direct drawing type waterless lithographic printing plate precursor as described in 11 above, wherein a silane coupling agent is previously coated on the heat-sensitive ink-receptive layer of the film.

13. A waterless planographic printing plate obtained by selectively exposing and developing the direct drawing type waterless planographic printing plate precursor described in any one of 1 to 10 above.

[0047]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, the direct drawing type means that an image is formed directly from a recording head on a printing plate without using a negative or positive film at the time of exposure.

Further, the optical density here means the Ratten filter No. Macbeth reflection densitometer using 106
The numerical value when measured with RD-514.

The direct drawing type waterless planographic printing plate used in the present invention will be described below.

The present invention is characterized in that a metal ink-receptive heat-sensitive layer is provided on the silicone rubber layer.

The ink-receptive heat-sensitive layer used here is
It is preferable that the laser light be efficiently absorbed and the heat thereof causes a partial or complete evaporation or melting.

First, in order to efficiently absorb the laser light, the wavelength of the semiconductor laser used as the light source (800
The absorption rate for (near nm) becomes important.

Then, the optical density of the printing plate is measured as an index of the absorptance for the light near 800 nm. That is, the higher the optical density, the more efficiently the laser light can be absorbed.

The optical density is preferably 0.6 to 2.5, more preferably 0.8 to 1.8. When the optical density is less than 0.6, the sensitivity of the printing plate is likely to be lowered because the laser light is not efficiently absorbed, and when the optical density is more than 2.5, the film thickness becomes large, and therefore an image is formed. Extra energy is required and the sensitivity is reduced.

As such a metallic material, a material having a metallic luster and a smaller size is preferred. This is because as the metallic luster increases, the reflection of laser light on the surface also increases.

Specific examples of such a metal include tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc, copper, indium, manganese, lead, phosphorus, bismuth, cobalt, palladium,
Bismuth is preferably used, more preferably tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth.

Further, as the metal which partly or wholly evaporates or melts, any metal having a melting point of 1500 (K) or less can be preferably used.
It is more preferably 930 (K) or less. Melting point 150
If it is larger than 0 (K), it takes time to evaporate or melt even if the laser beam is irradiated, and as a result, the sensitivity of the plate material decreases.

Specifically, tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth, which are metals having a melting point of 930 (K) or less, are preferably used, and more preferably tellurium. ,
They are tin and zinc. These metals are particularly preferable because they easily evaporate or melt by heat when the thin film is irradiated with laser light.

Further, these metals are particularly preferable because the melting point is more easily lowered and the sensitivity as a printing plate is improved by using two or three kinds of alloys.

The combination for forming such an alloy is selected from the group consisting of tellurium, tin, antimony, gallium, bismuth and zinc described in claims 4 and 5.

Specifically, as alloys of two kinds of combination, tellurium / tin, tellurium / antimony, tellurium / gallium, tellurium / bismuth, tellurium / zinc, tin /
Zinc is preferable, and more preferable is an alloy of tellurium / zinc, tellurium / tin, tin / zinc.

The three types of alloys are tellurium / tin /
Zinc, tellurium / gallium / zinc, tin / antimony / zinc, tin / bismuth / zinc are preferable, and more preferable are alloys of tellurium / tin / zinc and tin / antimony / zinc.

At this time, the film thickness of the thin film also greatly affects the sensitivity of the plate material. That is, if the film thickness is too thick, extra energy is required to evaporate and melt the thin film, and thus the sensitivity of the plate material decreases. Therefore, the film thickness is preferably 50 to 10000 angstroms, more preferably 200 to 2000 angstroms.
Angstrom.

As a method for forming such a thin film, it is preferable to carry out either of vacuum vapor deposition and sputtering.

In the vacuum evaporation, it is general to heat and evaporate metal and carbon in a decompression container of 10 ⁻⁴ to 10 ⁻⁷ mmHg to form a thin film on the surface of the substrate.

Sputtering is 10 ^-1 to 10 ^-3 mmHg
Direct current or alternating current voltage is applied to the pair of electrodes in the decompression container to cause glow discharge, and a thin film is formed on the substrate by utilizing the sputtering phenomenon of the cathode.

As a substrate for forming the above ink-receptive heat-sensitive layer, a dimensionally stable plate is used.
Such dimensionally stable plate-like objects include those conventionally used as substrates for printing plates, and they can be suitably used. Such substrates include paper, paper on which plastics (for example, polyethylene, polypropylene, polystyrene, etc.) are laminated, for example, plates of metal such as aluminum (including aluminum alloys), zinc, copper, etc., for example, cellulose, carboxy. Plastic films such as methylcellulose, cellulose acetate, polyethylene terephthalate, polyethylene, polyester, polyamide, polyimide, polystyrene, polypropylene, polycarbonate, polyvinyl acetate, etc .; Alternatively, vapor-deposited paper or plastic film is included. Among these substrates, the aluminum plate is particularly preferable because it is extremely stable in dimension and inexpensive.
Further, a polyethylene terephthalate film used as a substrate for light printing is also preferably used.

The waterless planographic printing plate used in the present invention may be provided with a primer layer in order to strengthen the adhesion between the substrate and the silicone rubber layer. The primer layer of the direct drawing type waterless planographic printing plate precursor used in the invention is required to satisfy the following conditions. That is, the substrate is well adhered to the silicone rubber layer, is stable over time, and has good solvent resistance to the solvent of the developer. Japanese Patent Publication No. 61-5421 for satisfying such conditions.
In addition to those containing an epoxy resin as disclosed in JP-A-9, a polyurethane resin, a phenol resin, an acrylic resin, an alkyd resin, a polyester resin, a polyamide resin, a melamine resin, a urea resin, a benzoguanamine resin,
Vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, polyvinyl butyral resin, ethylene-vinyl acetate copolymer, polycarbonate resin, polyacrylonitrile-butadiene copolymer, polyether resin, polyether sulfone resin, milk casein, gelatin, etc. Can be used. These resins may be used alone or in combination of two or more.

Of these, polyurethane resins, polyester resins, acrylic resins, epoxy resins, urea resins and the like are preferably used alone or in admixture of two or more.

As the anchor agent constituting the primer layer, a known adhesive such as a silane coupling agent can be used, and organic titanate is also effective.

It is also optional to add a surfactant for the purpose of improving the coatability.

In the exposed area of the printing plate, the primer layer is exposed and becomes an image area. Therefore, it is preferable to add an additive such as a dye to the primer layer to improve the plate inspection property.

The composition for forming the above-mentioned primer layer is prepared as a composition solution by dissolving it in a suitable organic solvent such as DMF, methyl ethyl ketone, methyl isobutyl ketone, dioxane, toluene, xylene and THF. A primer layer is formed by uniformly applying the composition solution on a substrate and heating it at a required temperature for a required time.

The primer layer has a thickness of 0.5 as a coating layer.
~ 50 g / m ² is preferred, more preferably 1-10.
g / m ² . When the thickness is less than 0.5 g / m ² , the effect of blocking morphological defects and chemical adverse effects on the surface of the substrate is reduced, and when it is more than 50 g / m ^2, it is disadvantageous from the economical point of view, so the above range is preferable.

For the silicone rubber layer formed on the substrate or on the primer layer, all conventional silicone rubber compositions for waterless lithographic printing plates can be used.

Such a silicone rubber layer is obtained by sparsely cross-linking a linear organopolysiloxane (preferably dimethylpolysiloxane), and a typical silicone rubber layer has the following formula (I). It has a repeating unit as shown in.

[0077]

Embedded image (Here, n is an integer of 2 or more. R has 1 to 10 carbon atoms.)
Alkyl, aryl, or cyanoalkyl group. Preferably, 40% or less of the whole R is vinyl, phenyl, vinyl halide, or halogenated phenyl, and 60% or more of R is a methyl group. Further, it has at least one or more hydroxyl group in the molecular chain at the chain end or in the form of a side chain. In the case of the silicone rubber layer applied to the printing plate of the present invention, a silicone rubber (R
TV, LTV type silicone rubber) can be used. As such a silicone rubber, one in which a part of R of the organopolysiloxane chain is replaced by H can be used, but usually, the end groups represented by the following formulas (II), (III) and (IV) are not used. Are crosslinked by the condensation of. In some cases, an excess of a crosslinking agent may be present.

[0078]

Embedded image

Embedded image

Embedded image (Where R is the same as R described above; R1, R2
Is a monovalent lower alkyl group, and Ac is an acetyl group. ) Silicone rubber which performs such condensation type crosslinking includes:
Metal carboxylates such as tin, zinc, lead, calcium, manganese, for example, dibutyltin laurate, tin (II) octoate, naphthenates, etc., or catalysts such as chloroplatinic acid are added.

Further, the silicone rubber layer crosslinked by the addition reaction of the following formulas (V) and (VI) used in the present invention is a polyvalent hydrogenorganopolysiloxane and two or more in one molecule. A composition obtained by reaction with a polysiloxane having a bond of the formula (VI), preferably a composition comprising the following components, is crosslinked and cured.

[0080]

Embedded image

[Chemical 6] (1) 100 parts by weight of organopolysiloxane having at least two alkenyl groups (preferably vinyl groups) directly bonded to silicon atoms in one molecule (2) Organo having at least two groups of formula (V) in one molecule Hydrogen polysiloxane 0.1 to 1000 parts by weight (3) Addition catalyst 0.00001 to 10 parts by weight The alkenyl group of the component (1) may be at the terminal or in the middle of the molecular chain, and may be an organic compound other than the alkenyl group. As a basis,
It is a substituted or unsubstituted alkyl group or aryl group.
Component (1) preferably has a small amount of hydroxyl groups.
The component (2) reacts with the component (1) to form a silicone rubber layer, and plays a role of imparting adhesiveness to the heat-sensitive destruction layer. The hydrogen group of the component (2) may be at the terminal of the molecular chain or at the middle, and 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 in terms of improving ink repellency. The molecular structure of component (1) and component (2) may be linear, cyclic or branched, and it is preferable that at least one of them has a molecular weight of more than 1000 from the viewpoint of rubber physical properties. It is preferred that the molecular weight of) exceeds 1000. Examples of the component (1) include α, ω-divinylpolydimethylsiloxane and a (methylvinylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, and the component (2) has a hydrogen group at both terminals. Examples thereof include polydimethyl siloxane, α, ω-dimethyl polymethyl hydrogen siloxane, (methyl hydrogen siloxane) (dimethyl siloxane) copolymer having methyl groups at both ends, and cyclic polymethyl hydrogen siloxane. The addition catalyst of the component (3) is arbitrarily selected from known catalysts, and is particularly preferably a platinum compound, such as platinum alone, platinum chloride, chloroplatinic acid, and olefin-coordinated platinum. In order to control the curing rate of these compositions, organopolysiloxanes containing vinyl groups such as tetracyclo (methylvinyl) siloxane, alcohols containing carbon-carbon triple bonds, acetone, methyl ethyl ketone, methanol, ethanol, It is also possible to add a crosslinking inhibitor such as propylene glycol monomethyl ether. These compositions have the characteristic that, when the three components are mixed, an addition reaction occurs and curing starts, but the curing rate increases rapidly as the reaction temperature increases. Therefore, the pot life until rubberization of the composition is lengthened,
In addition, for the purpose of shortening the curing time on the photosensitive layer, the curing conditions of the composition should be a temperature condition in which the characteristics of the substrate and the photosensitive layer do not change, and be kept at a high temperature until completely cured. It is preferable in terms of stability of adhesive force with the photosensitive layer.

In addition to these compositions, a silane compound is added to the silicone rubber layer for the purpose of improving the adhesiveness to the ink-receptive heat-sensitive layer, or the silicone rubber layer and the ink-receptive heat-sensitive layer or silicone. It is preferable to provide a silane compound layer between the rubber layer and the substrate.

As such a silane-based compound, in addition to a known silane coupling agent, any compound having a silyl group can be used. In the present invention, an acrylic silane or a methacrylic silane ( Hereinafter, both are collectively referred to as (meth) acrylsilane), and unsaturated group-containing silane coupling agents such as vinylsilane and allylsilane, and functional group-containing silane coupling agents such as epoxysilane, aminosilane, and mercaptosilane are preferably used.

Among these, since the unsaturated group-containing silane coupling agent copolymerizes with other monomers and develops an adhesive force at the interface with the silicone layer when the heat-sensitive destruction layer is subjected to light or heat curing, It effectively acts on the adhesion of the heat-sensitive destructive layer in the present invention.

Specific examples of the (meth) acrylsilane include N- (3- (meth) acryloxy-2-hydroxypropyl) -3-aminopropyltriethoxysilane and bis ((meth) acryloxypropyl)- 1, 1,
3,3-Tetramethyldisiloxane, 2- (meth) acryloxyethyldimethyl (3- (trimethoxysilyl)
Propyl) ammonium chloride, (meth) acryloxypropylbis (trimethylsiloxy) methylsilane, 3- (meth) acryloxypropyldimethylchlorosilane, 3- (meth) acryloxypropylmethyldichlorosilane, 3- (meth) acryloxypropyltri Chlorosilane, 3- (meth) acryloxypropyldimethylethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropyldimethylmethoxysilane 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth)
Acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylpentamethyldisiloxane,
3- (meth) acryloxypropyltris (methoxyethoxy) silane, 3- (meth) acryloxytris (trimethylsiloxy) silane, 2- (trimethylsiloxy) ethyl (meth) acrylate, trimethylsilyl (meth) acrylate and the like can be mentioned. However, preferably,
3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyldimethylethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3 -(Meth) acryloxypropyldimethylmethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, and the like.

Further, vinylsilane and allylsilane exhibit an adhesive force by reacting with hydrogenpolysiloxane, especially when the lower silicone rubber layer is an addition type.

Specific examples of vinylsilanes include bis (dimethylamino) methylvinylsilane, 1-bromovinyltrimethylsilane, chloromethyldimethylvinylsilane, 3-chloropropyldimethylvinylsilane, 1-chlorovinyltrichlorosilane and N, N-dimethylamino. Vinyldiethoxysilane, diphenylvinylchlorosilane, diphenylvinylethoxysilane, 1,3-divinyl-1,3-dimethyl-1,3-dichlorodisiloxane, divinyldimethylsilane, 1,3-divinyl-1,
3-diphenyl-1,3-dimethyldisilazane, 1,3
-Divinyl-1,3-diphenyl-1,3-dimethyldisiloxane, 1,3-divinyltetratetraethoxydisiloxane, 1,3-divinyltetramethyldisilazane, 1,3-divinyltetramethyldisiloxane, 1,
4-divinyl-1,1,4,4-tetramethyldisilylethylene, phenyldimethylvinylsilane, phenylmethylvinylchlorosilane, phenylmethylvinylsilane, phenylvinylchlorosilane, phenylvinyldimethoxysilane, 1,1,3,3-tetravinyl Dimethyldisiloxane, tetravinylsilane, 1,3,5,7-
Tetravinyltetramethylcyclotetrasiloxane, triphenylvinylsilane, trivinylmethylsilane,
1,3,5-trivinyl-1,1,3,5,5-pentamethyltrisiloxane, vinyldiethylmethylsilane,
Vinyldimethylchlorosilane, vinyldimethylethoxysilane, vinylethyldichlorosilane, vinylmethyldiacetoxysilane, vinylmethyldichlorosilane, vinylmethyldiethoxysilane, 1-vinylsilatrane, vinyltriacetoxysilane, vinyltrichlorosilane,
Vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltrimethoxysilane, vinyltrimethylsilane, vinyltriphenoxysilane, vinyltris (tri-s-butoxysiloxanyl) silane, vinyltris (t-butylperoxy) silane, vinyltris ( 2-methoxyethoxy) silane and vinyltris (trimethylsiloxy) silane can be mentioned, but preferably,
They are vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, vinyltrimethoxysilane, divinyldiethoxysilane and vinyltriacetoxysilane.

Specific examples of the allylsilane include allyldimethylchlorosilane, allyldimethylsilane, allylmethyldichlorosilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diallyldiethoxysilane, diallyldimethoxysilane and triallylethoxysilane. , Triallylmethoxysilane,
Phenylallyldiethoxysilane, phenylallyldimethoxysilane, phenyldiallylethoxysilane, phenyldiallylmethoxysilane, allyltrimethylsilane, diallyldichlorosilane, diallyldimethylsilane, diphenyldiallylsilane, phenylallyldichlorosilane, tetraallyloxysilane, O-trimethylsilyl Examples include allyl alcohol, but preferably allyltriethoxysilane, allyltrimethoxysilane,
These are diallyldiethoxysilane and diallyldimethoxysilane.

The epoxysilane is 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane,
As aminosilane, N-2- (aminoethyl) -3
-Aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, and as the mercaptosilane, 3-mercaptopropyltrimethoxysilane, 3-mercapto Examples include propyltriethoxysilane.

The addition amount of such a silane compound is
The amount is preferably 0.01 to 20% by weight, more preferably 0.05 to 10% by weight, based on the total heat-sensitive destruction layer composition.

Alternatively, the silane coupling agent may be dissolved in an appropriate solvent and applied in a dilute solution onto the silicone rubber layer or the substrate to be used as the adhesive layer.

In this case, the film thickness of the silane coupling agent layer is sufficient if the film thickness is such that a monomolecular film of the silane coupling agent is formed. Specifically, it is preferably 1000 angstroms or less. It is preferably 500 angstroms or less.

When the film thickness is thicker than 1000 angstroms, the adhesiveness with the silicone rubber layer is likely to be lowered, and the printing durability and solvent resistance of the printing plate are reduced.

In addition to the above, it is optional to add a hydroxyl group-containing organopolysiloxane or a hydrolyzable functional group-containing silane (or siloxane), which is a composition of the condensed silicone rubber layer, and to improve the rubber strength. For this purpose, it is optional to add a known filler such as silica.

The thickness of these silicone rubber layers is 0.5.
To 50 g / m ² , more preferably 0.5 to 50 g / m ^2.
10 g / m ² . When the film thickness is less than 0.5 g / m ² , the ink repellency of the printing plate tends to decrease, and
If it is larger than g / m ² , it is disadvantageous from an economic point of view.

For the purpose of protecting the surface of the waterless planographic printing plate precursor constructed as described above, the surface of the ink-receptive heat-sensitive layer is provided with a thin protective film having a plane or an uneven treatment. Alternatively, it is also possible to laminate a film having an ink-receptive heat-sensitive layer formed thereon in advance on the silicone rubber layer.

It is also possible to form a polymer coating film which is soluble in the developing solvent described in JP-A-5-323588.

In particular, when a protective film is laminated, laser exposure is performed on the protective film, and then the protective film is peeled to form a pattern on the printing plate. It is also possible to create.

Next, the method for producing the waterless planographic printing plate precursor according to the invention will be described.

First, a reverse roll coater on the substrate,
An ordinary coater such as an air knife coater or a Mayer bar coater, or a spin coater such as a whaler is used to coat the primer layer composition as necessary.
After curing at 300 ° C. for several minutes, the silicone rubber composition is applied and heat-treated at a temperature of 50 to 150 ° C. for several minutes to cure the rubber to form a silicone rubber layer.

An ink-receptive heat-sensitive layer is formed thereon by vapor deposition or sputtering, and a protective film is laminated or a protective layer is formed, if necessary.

At this time, it is also possible to laminate a film having an ink-receptive heat-sensitive layer previously formed thereon on the silicone rubber layer.

Further, for the purpose of improving the adhesiveness between the ink-receptive heat-sensitive layer and the silicone rubber layer, a silane coupling agent is applied in advance on the above-mentioned ink-receptive heat-sensitive layer, which is then coated with silicone rubber. It is also effective to laminate on the formed substrate.

The direct drawing type waterless planographic printing plate precursor thus obtained is imagewise exposed with a laser beam after the protective film is peeled off or from the protective film.

Laser light is usually used for exposure, and the light source at this time has an oscillation wavelength of 300 nm to 1500.
such as Ar ion laser, Kr ion laser, He-Ne laser, He-Cd laser, ruby laser, glass laser, semiconductor laser, YAG laser, titanium sapphire laser, dye laser, nitrogen laser, metal vapor laser in the range of nm. Various lasers can be used. Among them, the semiconductor laser is preferable because it is miniaturized due to the recent technical progress and is economically advantageous over other laser light sources.

The direct drawing type waterless planographic printing plate exposed by the above-mentioned method is subjected to peeling development or usual solvent development treatment, if necessary.

The developing solution used in the present invention includes, for example, water, one obtained by adding the polar solvent shown below to water, and aliphatic hydrocarbons (hexane, heptane, "Isopar E,
G, H "(trade names of isoparaffinic hydrocarbons manufactured by ESSO), gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.), and halogenated hydrocarbons (trichlene, etc.). A mixture obtained by adding at least one of the following polar solvents to a mixed solvent is preferably used.

Alcohols (methanol, ethanol,
Propanol, isopropanol, 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 monoethyl 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 acetate, etc.) Acid (2-ethylbutyric acid, Prong acid, caprylic acid, 2-ethylhexanoic acid, capric acid, oleic acid,
In addition, a known surfactant can be freely added to the above-mentioned developer composition. In addition, further alkaline agent,
For example, sodium carbonate, monoethanolamine, diethanolamine, diglycolamine, monoglycolamine, triethanolamine, sodium silicate, potassium silicate, potassium hydroxide, sodium borate and the like can be added.

When developing, these developing solutions may be impregnated into a non-woven fabric, absorbent cotton, cloth, sponge or the like, and the plate surface may be wiped off to develop.

For development, Japanese Patent Laid-Open No. 63-163357.
It is possible to suitably develop by pretreatment of the plate surface with the above-mentioned developing solution using an automatic developing machine as described in 1) and then rubbing the plate surface with a rotating brush while showering with tap water or the like.

Development can also be performed by spraying hot water or steam onto the plate surface instead of the above developing solution.

[0111]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

Examples 1 to 6 A primer solution having the following composition was applied on a degreased aluminum plate having a thickness of 0.24 mm and dried at 230 ° C. for 2 minutes to provide a 4 g / m ² primer layer. .

(A) Cancoat 90T-25-3094 (Epoxy phenolic resin manufactured by Kansai Paint Co., Ltd.) 15 parts by weight (b) Victoria Pure Blue BOH naphthalene sulfonic acid 0.1 part by weight (c) 85 parts by weight of dimethylformamide Next, a silicone rubber solution having the following composition was applied on this primer layer and dried at 120 ° C. for 2 minutes to give a thickness of 5 g.
/ M ² of silicone rubber layer was provided.

(A) Polydimethylsiloxane (molecular weight about 25,000, terminal hydroxyl group) 100 parts by weight (b) Ethyltriacetoxysilane 12 parts by weight (c) Dibutyltin diacetate 0.1 parts by weight (d) 3-Amino Propyltriethoxysilane 0.2 parts by weight (e) "Isopa-G" (manufactured by Exxon Chemical Co., Ltd.) 1200 parts by weight Then, a silane coupling agent solution having the following composition was applied onto the silicone layer, and 120 It was cured at a dew point of 30 ° C. for 2 minutes to form a silane coupling agent layer having a thickness of 0.01 g / m ² .

(A) 3-Aminopropyltrimethoxysilane 0.001 parts by weight (b) Toluene 100 parts by weight Next, the following was placed on a polypropylene film “Trephan” (manufactured by Toray Industries, Inc.) having a thickness of 80 μm. An ink-receptive heat-sensitive layer composition having a composition was formed by vacuum vapor deposition to provide an ink-receptive heat-sensitive layer.

(A) Metal (Table 1) This film and a substrate coated with a silane coupling agent are laminated using a calendar roller so that their coated surfaces are in contact with each other, and direct drawing type waterless planographic printing I got the original edition.

Then, the "trephane" of this printing plate precursor
Is peeled off, the metal layer is transferred onto the silicone layer, and the semiconductor laser (SLD-304XT,
Pulse exposure was performed using an output of 1 W, a wavelength of 809 nm, manufactured by Sony Corporation, with a beam diameter of 20 μm and an exposure time of 10 μs. At this time, the laser output was arbitrarily changed by an LD pulse modulation driving device, and the laser power on the plate was measured.

The image reproducibility of this printing plate was evaluated with a magnifying power of 50 times, the minimum laser power at which dots were formed was determined, and the sensitivity of the printing plate was measured from the result.

The obtained printing plate was attached to an offset printing machine (Komori Sprint 4-color machine), and was manufactured by Dainippon Ink and Chemicals, Inc. "Dry Ocolor" ink, indigo,
Printing was carried out on high-quality paper using red and yellow inks, and the temperature of the plate surface when stains were observed on the printed matter was evaluated as the background stain temperature.

Example 7 In Example 1, a silane coupling agent layer solution having the following composition was applied between the primer layer and the silicone rubber layer, and cured at 120 ° C. for 2 minutes at a dew point of 30 ° C. A direct drawing type waterless planographic printing plate precursor was prepared in the same manner except that a silane coupling agent layer having a thickness of 0.01 g / m ² was provided, and evaluated in the same manner.

(A) 3-mercaptopropyltrimethoxysilane 0.001 parts by weight (b) Toluene 100 parts by weight Comparative Examples 1 and 2 In Examples 1 and 2, a primer layer, an ink-receptive heat-sensitive material having the same composition on a substrate. Layer, silane coupling agent layer,
Silicone rubber layers were laminated in this order, and the rest was evaluated in the same manner. However, only the thickness of the silicone rubber layer,
It was 2 g / m ² .

In Table 1, it can be seen that the printing plate of the present invention has improved background stain resistance and sensitivity as compared with the comparative example.

[0123]

[Table 1]

[0124]

INDUSTRIAL APPLICABILITY The direct drawing type waterless planographic printing plate of the present invention has improved scumming resistance and sensitivity as compared with the conventional direct drawing type waterless planographic printing plate.

Claims (13)

[Claims] 1. A direct drawing type waterless planographic printing plate precursor comprising a substrate, a silicone rubber layer provided on the substrate, and an ink receiving heat sensitive layer provided on the silicone rubber layer. Direct drawing type waterless planographic printing plate precursor characterized in that is a thin metal film. 2. The direct drawing type waterless lithographic printing plate precursor as claimed in claim 1, wherein the ink-receptive heat-sensitive layer is a metal thin film having a melting point of 930 (K) or less. 3. A direct drawing type waterless lithographic printing plate precursor as claimed in claim 1, wherein the metal is any one of tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth. 4. The metal according to claim 1, wherein the metal is tellurium, tin,
A direct drawing type waterless planographic printing plate precursor characterized by being an alloy which is a combination of any two kinds of antimony, gallium, bismuth and zinc. 5. The metal according to claim 1, wherein the metal is tellurium, tin,
A direct drawing type waterless planographic printing plate precursor characterized by being an alloy made of a combination of any three kinds of antimony, gallium, bismuth and zinc. 6. A direct-drawing waterless planographic printing plate precursor according to claim 1, wherein the thickness of the ink-receptive heat-sensitive layer is 50 to 10,000 angstroms. 7. A direct-drawing waterless planographic printing plate precursor according to claim 1, wherein the ink-receptive heat-sensitive layer has an optical density of 0.6 to 2.5. 8. A direct drawing type waterless planographic printing plate precursor comprising a silane coupling agent layer provided between the silicone rubber layer and the ink-receptive heat-sensitive layer according to claim 1. 9. A direct drawing type waterless planographic printing plate precursor comprising a silane coupling agent layer provided between the substrate and the silicone rubber layer in claim 1. 10. The silicone rubber layer according to claim 1,
A waterless planographic printing plate precursor for direct drawing, characterized by containing a silane coupling agent. 11. A substrate having a silicone rubber layer surface on one side and a film having an ink-receptive heat-sensitive layer on one side,
A method for producing a direct drawing type waterless planographic printing plate precursor, which comprises laminating the silicone rubber layer surface side and the ink receptive heat sensitive layer surface side in contact with each other. 12. A method for producing a direct drawing type waterless lithographic printing plate precursor as described in claim 11, wherein a silane coupling agent is applied in advance on the ink-receptive heat-sensitive layer of the film. 13. A waterless planographic printing plate obtained by selectively exposing and developing the direct drawing type waterless planographic printing plate precursor according to any one of claims 1 to 10.