JP3484589B2 - Direct drawing type waterless planographic printing plate precursor - Google Patents

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 that can be printed without using a fountain solution, and more particularly to a direct drawing type waterless planographic printing plate precursor that can be directly plate-made by laser light. It is a thing.

[0002]

2. Description of the Related Art The so-called direct 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, quick in obtaining a printing plate in a short time, and various Taking advantage of features such as rationality that can be selected from the system according to quality and cost,
Not only in the light printing industry, but also in the fields of general offset printing and gravure printing.

In particular, recently, various types of lithographic printing materials of a new type have been developed due to rapid progress of output systems such as prepress systems, imagesetters and laser printers.

These lithographic printing plates are classified according to the plate making method: a method of irradiating with a laser beam, a method of writing with a thermal head, a method of partially applying a voltage with a pin electrode,
Examples thereof include a method of forming an ink repellent layer or an ink inking layer by inkjet.

Among them, the method using laser light is superior to other methods in terms of resolution and plate making speed,
There are many types.

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

As the photon mode type (1) High-sensitivity PS plate using photopolymer (2) Electrophotographic planographic printing plate using organic photoconductor or zinc oxide (3) Silver salt method planographic printing (4) Silver salt composite method planographic printing (5) Direct drawing master As a heat mode type, (6) Thermal destruction method planographic printing Is mentioned.

[0008]

[Problems to be Solved by the Invention] However, (1)
In this method, the apparatus is large because it mainly uses an argon ion laser as the laser light source, and because the printing plate also uses a high-sensitivity photopolymer, care must be taken when handling the printing plate and storage stability is required. There is a drawback that the property is likely to deteriorate.

The electrophotographic planographic printing plate of (2) has an advantage that it can be handled in a bright room, but dark decay becomes large between 2 and 5 minutes after charging of the photosensitive layer, so that exposure and development processing is carried out in a short time after charging. It is difficult to output large format with high resolution.

With respect to the silver salt method (3), a printing plate compatible with lasers of various wavelengths has been developed, but it has a problem that silver waste liquid is discharged, and its sensitivity is high, so handle it carefully. There is also a problem that requires.

In the silver salt composite type lithographic plate of (4), a high-sensitivity silver halide emulsion layer is provided on the photosensitive layer, the upper silver halide emulsion layer is exposed with an argon ion laser, and after development, ultraviolet rays are further used as a mask. Exposure and development are performed. However, since this printing plate has two exposure and development steps, there is a problem that the processing of the printing plate becomes complicated.

Although the direct drawing master of (5) does not directly write on the printing plate with a laser, it transfers the toner image formed by the laser printer onto the printing plate as an ink inking 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, Japanese Patent Laid-Open No. 6-199064, US
P5339737, USP5353705, EP0
580393, JP-A-6-55723, EP057.
No. 3091 and US Pat. No. 5,378,580 describe a direct drawing type waterless planographic printing plate precursor using a laser beam as a light source.

The heat-sensitive layer of this thermal destruction printing plate precursor is
Carbon black is used as the laser light absorbing compound, and nitrocellulose is used as the thermal decomposition compound. The carbon black absorbs the laser light to be converted into heat energy, and the heat destroys the 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,
It cannot be said that the light of the semiconductor laser used (wavelength near 800 nm) is absorbed efficiently.

This is one measure of the absorption efficiency of laser light, and when the optical density of the printing plate is the above particle size,
This is because it does not reach the maximum.

That is, the optical density becomes maximum when the particle diameter is around 20 μm, and decreases when it exceeds 30 μm. 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 smaller the particles, the more easily the carbon black itself becomes transparent and the lower the dispersibility of the particles.

In addition, since the carbon black of the above-mentioned patent has a high oil supply amount, that is, has a high structure structure, the particles agglomerate with each other, and the viscosity of the heat-sensitive layer solution becomes high, which makes the handling inconvenient. However, there is a problem that the coating film does not become uniform.

Further, in particular, JP-A-6-55723, 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 a heat sensitive layer.

This is advantageous in terms of resolution of the printing plate because the heat-sensitive layer is considerably thin, which is advantageous in terms of resolution of the printing plate. However, since the metal thin film itself reflects laser light to some extent, the printing plate is There was a problem that the sensitivity was poor.

In order to improve the drawbacks of the prior art, the present invention suppresses the reflection of laser light on the metal thin film by laminating a carbon thin film and a metal thin film, and absorbs the laser light efficiently, and It has become possible to perform exposure with lower energy than before.

As a result, a direct drawing type waterless lithographic printing plate having improved sensitivity can be provided.

[0030]

In order to achieve the above object, the present invention has the following constitution.

1. In a direct drawing type waterless planographic printing plate precursor in which a heat sensitive layer and a silicone rubber layer are sequentially laminated on a substrate, the heat sensitive layer is composed of a carbon thin film and a metal thin film. Original version.

2. 1. The direct drawing type waterless lithographic printing plate precursor as described in 1 above, wherein the heat sensitive layer is formed by forming a carbon thin film on a metal thin film.

3. In the above 1, the metal has a melting point of 200.
A direct drawing type waterless planographic printing plate precursor, which is a metal of 0 (K) or less.

4. In the above 1, the metal is at least one selected from the group consisting of titanium, aluminum, nickel, iron, chromium, tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth. Direct drawing type waterless planographic printing plate precursor.

5. In the above 1, the metal is a combination of any two kinds selected from the group consisting of tellurium, tin, antimony, gallium, bismuth and zinc,
Direct drawing type waterless planographic printing plate precursor characterized by being an alloy.

6. In the above 1, the metal is a combination of any three kinds selected from the group consisting of tellurium, tin, antimony, gallium, bismuth and zinc,
Direct drawing type waterless planographic printing plate precursor characterized by being an alloy.

7. In the above 1, the thickness of the heat sensitive layer is 1
A direct drawing type waterless planographic printing plate precursor characterized by having a thickness of 000 angstroms or less.

8. 1. The direct drawing type waterless planographic printing plate precursor as described in 1 above, wherein the heat sensitive layer has an optical density of 0.6 to 2.3.

9. 1. The direct drawing type waterless planographic printing plate precursor as described in 1 above, wherein a silane coupling agent layer is provided between the heat sensitive layer and the silicone rubber layer.

10. 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 9 above.

[0041]

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

Further, the optical density here means the Ratten filter No. Macbeth Densitometer RD with 106
-Numerical value when measured at 514.

Next, the direct drawing type waterless planographic printing plate used in the present invention will be explained.

It is important that the heat-sensitive layer used in the present invention efficiently absorbs laser light, and a part or all of which is momentarily evaporated or melted by the heat.

First, in order to absorb the laser light efficiently, 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 2.3, more preferably 0.8 to 1.8. If the optical density is less than 0.6, the sensitivity of the printing plate tends to decrease because the laser light is not absorbed efficiently, and even if the optical density is more than 2.3, the film thickness increases and an image is formed. Extra energy is required and the sensitivity decreases.

In order to keep the optical density within the above range, it is important to stack a carbon thin film and a metal thin film as the heat sensitive layer.

Regarding the order of lamination, it is more preferable to form the carbon thin film on the metal thin film because the effect of improving the sensitivity is great.

The metal used at this time is not particularly limited as long as it can be vapor-deposited or sputtered, but a metal having a melting point of 2000 (K) or less is preferable, and more preferably 1000 (K) or less.

If the melting point is higher than 2000 (K), it is difficult to form an image even if carbon is simultaneously vapor-deposited or sputtered.

Specifically, titanium is a preferable metal,
Aluminum, nickel, iron, chromium, tellurium, tin, antimony, gallium, magnesium, polonium, selenium,
There are thallium, zinc, and bismuth, and among them, tellurium, tin, antimony, gallium, bismuth, and zinc are more preferable.

This is because these metals are easily evaporated or melted by heat when the thin film is irradiated with laser light.

By using two or more kinds of the above metals as an alloy, the melting point can be further lowered and the sensitivity as a printing plate can be increased.

Specifically, alloys of tellurium and tin, tellurium and antimony, tellurium and gallium, tellurium and bismuth, tellurium and zinc are preferable, and more preferable are alloys of tellurium and zinc and tellurium and tin.

Among the three types of alloys, alloys of tellurium, tin and zinc, tellurium, gallium and zinc, tin, antimony and zinc, tin, bismuth and zinc are preferable, and more preferable are tellurium, tin, zinc and tin. It is an alloy of bismuth and zinc.

These materials are particularly preferable because they have a high optical density and a low melting point.

The thickness of the metal thin film is preferably 50 to 500 angstroms, more preferably 100 to 30 angstroms.
It is 0 angstrom.

Then, a carbon thin film is formed on or under these metal thin films.

In this case, the carbon thin film is preferably black to the extent that the reflection of the metal thin film is suppressed.

For that purpose, the thickness of the carbon thin film is 5
It is preferably 0 to 500 angstroms, more preferably 100 to 300 angstroms.

The film thickness ratio between the metal thin film and the carbon thin film also affects the sensitivity of the printing plate. Specifically, when the thickness of the metal thin film is 1, the carbon thin film preferably has a thickness of 1/4 to 6. If the film thickness ratio of the carbon thin film is smaller than 1/4, the effect of improving the sensitivity is not observed, and if it is larger than 6, it tends to be difficult to form the carbon thin film.

At this time, the film thickness of the entire heat-sensitive layer 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, so that the sensitivity of the plate material decreases.

Therefore, the film thickness is preferably 1000 angstroms or less, more preferably 300 angstroms or less.

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 or 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.

This method is preferable because a thin film can be formed relatively easily even with carbon having a high melting point.

In either method, carbon and metal
It is preferable that the film thickness ratio between the carbon thin film and the metal thin film falls within the above range by performing heating or voltage under appropriate conditions.

It is also important to provide a silane coupling agent layer on the heat sensitive layer in order to improve the adhesion between the heat sensitive layer and the silicone rubber layer.

As a result, the printing durability and solvent resistance of the printing plate are greatly improved.

As the silane coupling agent, vinyl silane, (meth) acryloyl silane, epoxy silane,
All known aminosilanes such as aminosilane, mercaptosilane and chlorosilane can be used, but of these, (meth) acryloylsilane, epoxysilane, aminosilane and mercaptosilane are preferably used.

Specifically, the (meth) acryloylsilane is 3- (meth) acryloylpropyltrimethoxysilane, 3- (meth) acryloylpropyltriethoxysilane, and the epoxysilane is 3-glycidoxy. Propyltrimethoxysilane, 2- (3,4
-Epoxycyclohexyl) ethyltrimethoxysilane, and as the aminosilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2
It is-(aminoethyl) -3-aminopropylmethyldimethoxysilane and 3-aminopropyltriethoxysilane, and examples of the mercaptosilane include 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane.

These silane coupling agents are dissolved in an appropriate solvent and applied as a dilute solution onto the heat-sensitive layer,
Perform heat cure.

The film thickness of the silane coupling agent layer is sufficient as long as a monomolecular film of the silane coupling agent is formed. Specifically, it is preferably 1000 angstroms or less, more preferably. It is 500 angstroms or less.

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

As a substrate for forming the above heat sensitive layer, a dimensionally stable plate is used. Examples of such a dimensionally stable plate-like material include those conventionally used as a substrate for a printing plate, and they can be preferably used. Such substrates include paper and plastic (eg polyethylene, polypropylene, polystyrene, etc.)
Laminated paper, for example, a metal plate such as aluminum (including aluminum alloy), zinc, copper, etc.,
For example, a plastic film such as cellulose, carboxymethyl cellulose, cellulose acetate, polyethylene terephthalate, polyethylene, polyester, polyamide, polyimide, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, or the like, or a metal as described above. Include laminated or vapor deposited paper or plastic film. Among these substrates, the aluminum plate is particularly preferable because it is remarkably dimensionally stable and inexpensive. 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 heat sensitive 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 and the heat-sensitive layer are well adhered, stable over time, and the solvent resistance of the developer to the solvent is good. As a material satisfying such a condition, in addition to a material containing an epoxy resin as shown in Japanese Patent Publication No. 61-54219, a polyurethane resin,
Phenol resin, acrylic resin, alkyd resin, polyester resin, polyamide resin, melamine resin, urea resin, 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 and the like 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 such a composition solution on a substrate and heating at a required temperature for a required time.

The thickness of the primer layer is 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.

As the uppermost silicone rubber 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.

[0088]

[Chemical 1] (Here, n is an integer of 2 or more. R has 1 to 10 carbon atoms.
Is an alkyl, aryl, or cyanoalkyl group. It is preferable that 40% or less of the total R is vinyl, phenyl, vinyl halide, or phenyl halide, and 60% or more of R is a methyl group. Further, it has at least one hydroxyl group in the molecular chain in the form of a chain end or a side chain. ) In the case of the silicone rubber layer applied to the printing plate of the present invention, silicone rubber (R
TV, LTV type silicone rubber) is used. As such a silicone rubber, R of an organopolysiloxane chain is used.
Although a part of H may be substituted with H, it is usually crosslinked by condensation of the terminal groups represented by the following formulas (II), (III) and (IV). In some cases, an excess amount of the cross-linking agent may be present.

[0089]

[Chemical 2]

[Chemical 3]

[Chemical 4] (Here, R is the same as R described above, and R1, R2
Is a monovalent lower alkyl group, and Ac is an acetyl group. ) Silicone rubber that performs such condensation-type crosslinking,
Metal carboxylates of tin, zinc, lead, calcium, manganese, etc., such as dibutyltin laurate, tin (II) octoate, naphthenates, etc., or catalysts such as chloroplatinic acid are added.

Further, in the present invention, addition type silicone rubber may be used in addition to the above condensation type silicone rubber.

As the addition type silicone rubber, it is preferable to use a hydrogen polysiloxane having a Si—H bond and a vinyl polysiloxane having a CH═CH bond which are crosslinked and cured with a platinum catalyst as shown below. .

(1) 100 parts by weight of organopolysiloxane having at least two alkenyl groups (preferably vinyl groups) directly bonded to a silicon atom in one molecule (2) at least 2 groups of formula (V) in one molecule Organohydrogenpolysiloxane having 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 other than the alkenyl group. As the organic group of
It is a substituted or unsubstituted alkyl group or aryl group.
The component (1) may have a small amount of hydroxyl groups. The component (2) reacts with the component (1) to form a silicone rubber layer,
It plays a role of imparting adhesiveness to the photosensitive layer. The hydrogen group of the component (2) may be at the terminal or in the middle of the molecular chain, and the organic group other than hydrogen is selected from the same as the component (1). The organic groups of the components (1) and (2) preferably have a methyl group content of 60% or more of the total number of the groups from the viewpoint of improving the ink repellency. Component (1) and component (2)
The molecular structure of 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, and further, the molecular weight of component (2) may exceed 1,000. preferable. 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. Polydimethylsiloxane, α, ω-
Examples thereof include 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 ones, but a platinum-based compound is particularly desirable, and platinum simple substance, platinum chloride, chloroplatinic acid, olefin coordinated platinum and the like are exemplified. For the purpose of controlling the curing rate of these compositions, vinyl group-containing organopolysiloxane such as tetracyclo (methylvinyl) siloxane and carbon-carbon triple bond-containing alcohol-
It is also possible to add a crosslinking inhibitor such as alcohol, acetone, methyl ethyl ketone, methanol, ethanol and propylene glycol monomethyl ether. These compositions are characterized in that an addition reaction occurs at the time when the three components are mixed and curing begins, but the curing rate rapidly increases as the reaction temperature increases. Therefore, for the purpose of prolonging the pot life of the composition until rubberization and shortening the curing time on the photosensitive layer, the curing conditions of the composition are a temperature condition in which the characteristics of the substrate and the photosensitive layer are not changed, Further, it is preferable to keep the temperature at a high temperature until it is completely cured, from the viewpoint of stability of the adhesive force with the photosensitive layer.

In addition to these compositions, it is also effective to add the above-mentioned known silane coupling agent for the purpose of improving the adhesion to the heat sensitive layer.

When the silane coupling agent is added to the silicone rubber layer, it is not necessary to provide the silane coupling agent layer.

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 condensation type 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.
˜50 g / m ² is preferred, and more preferably 0.5˜.
It is 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 economical point of view.

For the purpose of protecting the silicone rubber layer on the surface of the waterless lithographic printing plate precursor constructed as described above, a thin protective film having a plane or a concavo-convex surface is laminated on the surface of the silicone rubber layer. It is also possible to form a polymer coating film which can be dissolved 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 off to form a pattern on the printing plate. It is also possible to create.

Next, a method for producing a waterless planographic printing plate in the present invention will be described. An ordinary coater such as a reverse roll coater, an air knife coater, and a Mayer bar coater or a spin coater such as a whaler was applied on the substrate, and the primer layer composition was applied if necessary and cured at 100 to 300 ° C. for several minutes. After that, a heat-sensitive layer is formed by vapor deposition or sputtering, a 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 layer.

Then, if necessary, a protective film is laminated or a protective layer is formed.

The directly imageable waterless planographic printing plate precursor thus obtained is imagewise exposed with a laser beam after peeling off the protective film.

Laser light is usually used for the 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 following polar solvent to water, and aliphatic hydrocarbons (hexane, heptane, "Isopar E,
G, H "(trade name of ESSO-made isoparaffinic hydrocarbon), gasoline, kerosene, etc., aromatic hydrocarbons (toluene, xylene, etc.), halogenated hydrocarbons (tricrene, etc.), etc. A mixed solvent containing at least one of the following polar solvents 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.) Carvone Acid (2-ethylbutyric acid, Prong acid, caprylic acid, 2-ethylhexanoic acid, capric acid, oleic acid,
Lauric acid, etc.) Also, a known surfactant may be freely added to the above-mentioned developer composition. In addition, an 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.

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

At the time of developing, the developing solution can be developed by impregnating a non-woven fabric, absorbent cotton, cloth, sponge or the like with these developing solutions and wiping the plate surface.

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.

[0110]

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

Examples 1 to 5 On a degreased aluminum plate having a thickness of 0.24 mm, a primer solution having the following composition was applied, dried at 230 ° C. for 1 minute, and a primer layer of 3 g / m ² was provided. .

(A) Cancoat 90T-25-3094 (Kansai Paint Co., Ltd., epoxy phenolic resin) 15 parts by weight (b) Victoria Pure Blue BOH naphthalene sulfonic acid 0.1 part by weight (c) Dimethyl Formamide 85 parts by weight Next, a heat-sensitive layer composition having the following composition was formed on this primer layer by vacuum vapor deposition to provide a heat-sensitive layer.

(A) Metal (Table 1) Subsequently, a carbon thin film was formed on the metal thin film by sputtering so as to have a film thickness of 200 〓, and a heat sensitive layer was provided.

Further, the following silane coupling agent solution was applied onto the heat sensitive layer and dried at 120 ° C. for 2 minutes to form an adhesive layer.

(A) 3-Aminopropyltrimethoxysilane 1 part by weight (b) Ethanol 1000 parts by weight Finally, a silicone rubber solution having the following composition was applied and dried at 120 ° C. for 2 minutes to give a thickness of 3 g / An m ² silicone rubber layer was provided.

(A) Polydimethylsiloxane (molecular weight about 35,000, terminal hydroxyl group) 100 parts by weight (b) ethyltriacetoxysilane 12 parts by weight (c) dibutyltin diacetate 0.1 parts by weight (d) "isopar" G ”(manufactured by Exxon Chemical Co., Ltd.) 1200 parts by weight The laminated plate obtained as described above is laminated with a polyester film“ Lumirror ”(manufactured by Toray Co., Ltd.) having a thickness of 8 μm using a calendar roller, A direct drawing type waterless planographic printing plate precursor was obtained.

After that, the "lumirror" of the printing plate precursor was peeled off and the semiconductor laser (SL) mounted on the XY table was peeled off.
D-304XT, output 1W, wavelength 809nm, manufactured by Sony Corporation, beam diameter 20μm, exposure time 1
Pulse exposure was performed for 0 μs. At this time, the laser output is L
The laser power on the printing plate was measured while arbitrarily changing it with a D pulse modulation driving device.

Subsequently, rubbing with a cotton pad impregnated with a developer having the following composition was carried out to develop.

(A) 80 parts by weight of water (b) 20 parts by weight of diethylene glycol mono-2-ethylhexyl ether The image reproducibility of this printing plate was evaluated with a magnifying power of 50 to determine the minimum laser power for forming dots. Then, 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. "Dryo Color" ink, indigo,
Printing was carried out on high-quality paper using red and yellow inks, and the number of sheets showing damage on the plate surface was evaluated as printing durability.

Comparative Examples 1 and 2 In Example 1, the heat-sensitive layer was a vapor-deposited film of only copper or chromium, and a silane coupling agent layer was not provided.
A plate was prepared and evaluated in the same manner except for the above.

As shown in Table 1, it can be seen that the printing plate of the present invention has high sensitivity.

Further, it is understood that the printing durability of the printing plate is improved by providing the silane coupling agent layer.

[0124]

[Table 1]

[0125]

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

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Claims (10)

(57) [Claims] 1. A direct drawing type waterless planographic printing plate precursor in which a heat sensitive layer and a silicone rubber layer are sequentially laminated on a substrate, wherein the heat sensitive layer comprises a carbon thin film and a metal thin film. Waterless planographic printing plate original. 2. A direct drawing type waterless lithographic printing plate precursor as claimed in claim 1, wherein the heat sensitive layer is formed by forming a carbon thin film on a metal thin film. 3. The metal according to claim 1, wherein the metal has a melting point of 2000.
(K) A direct drawing type waterless planographic printing plate precursor characterized by being the following metals. 4. The metal according to claim 1, wherein the metal is at least one selected from the group consisting of titanium, aluminum, nickel, iron, chromium, tellurium, tin, antimony, gallium, magnesium, polonium, selenium, thallium, zinc and bismuth. A direct drawing type waterless planographic printing plate precursor characterized by 5. The metal according to claim 1, wherein the metal is a combination of any two kinds selected from the group consisting of tellurium, tin, antimony, gallium, bismuth and zinc.
Direct drawing type waterless planographic printing plate precursor characterized by being an alloy. 6. The metal according to claim 1, wherein the metal is a combination of any three kinds selected from the group consisting of tellurium, tin, antimony, gallium, bismuth and zinc.
Direct drawing type waterless planographic printing plate precursor characterized by being an alloy. 7. The heat sensitive layer according to claim 1, wherein the film thickness is 10
A direct drawing type waterless planographic printing plate precursor characterized by having a thickness of 00 angstroms or less. 8. A direct drawing type waterless planographic printing plate precursor as claimed in claim 1, wherein the heat sensitive layer has an optical density of 0.6 to 2.3. 9. A direct-drawing waterless planographic printing plate precursor according to claim 1, wherein a silane coupling agent layer is provided between the heat-sensitive layer and the silicone rubber layer. 10. 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 9.