JP7700690B2 - Waterless lithographic printing plate precursor and method for producing waterless lithographic printing plate using same - Google Patents

Description

The present invention relates to a waterless lithographic printing plate precursor, a method for producing a waterless lithographic printing plate using the same, and a composition for forming a metal chelate-containing silicone layer.

There are various printing methods, including letterpress printing, intaglio printing, stencil (screen) printing, and lithographic printing, and printing is carried out by taking advantage of the characteristics of each method. Among these, lithographic printing is advantageous over other printing methods in that it can produce highly detailed prints. Printing plates used in lithographic printing (hereafter referred to as lithographic printing plates) are broadly divided into those in which the non-printing areas are made ink-repellent by the action of dampening water, and those in which silicone or fluororesin is used for the ink-repellent non-printing areas without using dampening water.

Various proposals have been made so far regarding the technology of obtaining a waterless lithographic printing plate using silicone as an ink-repellent non-printing portion without going through a development process. For example, as a technology using a photocatalyst, a development-free photosensitive lithographic printing plate that does not require dampening water and is formed by providing a layer containing polyorganosiloxane in which photocatalytic semiconductor particles that are at least hydrophilized by exposure are dispersed on a support (see, for example, Patent Document 1), and a pattern-forming body that has a photocatalyst-containing layer on a substrate, the photocatalyst-containing layer containing silicone containing epoxy groups as organo groups bonded to silicon atoms as a binder and as a substance whose wettability changes due to the action of the photocatalyst, and the photocatalyst-containing layer has a pattern with different wettability formed on its surface by changing the wettability of the silicone due to the action of the photocatalyst accompanying pattern exposure (see, for example, Patent Document 2). In addition, as a method for manufacturing a printing plate having a first silicone layer and a second silicone layer on a support, which have different ink receptivity, a method for irradiating a laser beam from the second silicone layer side and ablating the second silicone layer in the portion irradiated with the laser beam, or the second silicone layer and the upper portion of the first silicone layer (see, for example, Patent Document 3), and as a method for manufacturing a printing member having a support and a layer consisting of an ink-repelling portion and an ink-receiving portion, a method for irradiating an electron beam or vacuum ultraviolet light to the layer consisting of the ink-repelling portion to draw a pattern of the ink-receiving portion (see, for example, Patent Document 4) have been proposed.

Japanese Patent Application Publication No. 11-305423 JP 2009-271548 A International Publication No. 2019/203263 JP 2021-66175 A

The lithographic printing plates described in Patent Documents 1 and 2 can be obtained by irradiation with ultraviolet light. However, the lithographic printing plate described in Patent Document 1 contains hydrophilic photocatalyst particles in hydrophobic silicone at a high density, and therefore, in the manufacture of the lithographic printing plate precursor, which is the precursor before the printing and non-printing areas are formed on the lithographic printing plate, the photocatalyst particles are prone to aggregation and sedimentation, posing a problem in productivity. The lithographic printing plate described in Patent Document 2 is capable of dispersing photocatalyst particles, but has problems with ink repellency and printing durability.

The waterless lithographic printing plate precursor described in Patent Document 3 has the problem that it is prone to ablation dust generation due to exposure to high-power ultraviolet to infrared lasers. The ablation dust collection device leads to an increase in size of the device. Furthermore, ablation dust that is not completely collected tends to adhere to the surface of the waterless lithographic printing plate, affecting print quality.

The waterless lithographic printing plate precursor described in Patent Document 4 uses electron beams or vacuum ultraviolet light, so irradiation in a nitrogen atmosphere or vacuum is required. This makes it unavoidable to increase the size of the equipment. In addition, electron beams and vacuum ultraviolet light are not commonly used in the manufacture of printing plates, so there was a demand for technology that would enable imaging using a general-purpose exposure machine.

The problem that the present invention aims to solve is to provide a waterless lithographic printing plate precursor that can be patterned using a general-purpose exposure machine, generates little ablation dust during exposure, does not require a development process, and can produce a waterless lithographic printing plate that has good ink repellency, ink receptivity, and printing durability.

In order to solve the above problems, the waterless lithographic printing plate precursor of the present invention is a waterless lithographic printing plate precursor having a metal chelate-containing silicone layer on a support, and a metal concentration derived from the metal chelate in the metal chelate-containing silicone layer, as measured by X-ray photoelectric spectroscopy, of 0.2 to 1.8 atom %.

The waterless lithographic printing plate precursor of the present invention can be pattern-exposed with a general-purpose laser, which does not require exposure under a nitrogen atmosphere or vacuum, and generates little ablation dust during exposure. With the lithographic printing plate precursor of the present invention, a waterless lithographic printing plate having good ink repellency, ink receptivity, and printing durability can be obtained without going through a development process.

The waterless lithographic printing plate precursor (hereinafter sometimes abbreviated as "printing plate precursor") of the present invention is a precursor before the formation of the ink-receiving portion/ink-repelling portion on a waterless lithographic printing plate (hereinafter sometimes abbreviated as "printing plate"), and has a metal chelate-containing silicone layer on a support. The support has the function of maintaining the shape of the printing plate precursor or printing plate. The metal chelate-containing silicone layer has the function of repelling ink.

Preferred materials for the support include dimensionally stable metals and plastics. Specific examples include metals such as aluminum, iron, zinc, and copper, alloys containing these metals as the main component, plastics such as epoxy resins, phenolic resins, ester resins, vinyl ester resins, amide resins, and imide resins, and fiber-reinforced plastics that contain these plastics and fibers such as glass fiber, carbon fiber, aramid fiber, polyethylene fiber, Zylon fiber, and boron fiber. Aluminum alloys and fiber-reinforced plastics are preferred because they are lightweight and easy to handle.

Examples of the shape of the support include plate-like, roll-like, cylindrical, and columnar shapes. When a cylindrical or columnar support is used, a seamless waterless lithographic printing plate precursor capable of printing a continuous pattern is obtained. A cylindrical shape is more preferable as the shape of the support for the seamless waterless lithographic printing plate precursor, since it is lighter and easier to handle. The cylindrical support is preferably the plate cylinder of a printing press, since printing can be performed immediately after the printing plate is produced from the printing plate precursor. In particular, it is more preferable for the cylindrical support to be a plate cylinder sleeve that can be detached from the plate cylinder shaft of a printing press, since the series of steps up to the production of a seamless waterless lithographic printing plate and operations such as regenerating the support after printing can be performed outside the printing press.

If the support is plate-shaped, the dimensions (length, width, thickness, etc.) of the support should be selected to be appropriate for the printing press to be used. If the support is cylindrical, the diameter and width should be selected to be appropriate for the plate cylinder of the printing press to be used.

The support surface may be subjected to a surface treatment such as corona discharge treatment or glow discharge treatment, which can increase the adhesive strength between the support and the metal chelate-containing silicone layer. A primer layer (adhesive layer) may also be provided between the support and the metal chelate-containing silicone layer. These may also be used in combination.

Next, the metal chelate-containing silicone layer will be described. In the present invention, the metal chelate-containing silicone layer refers to a silicone layer containing 3% by mass or more of a metal chelate compound. By including the metal chelate compound, the exposed area can be changed to ink-receptive properties by pattern exposure with a general-purpose laser.

A metal chelate compound refers to a compound that has one or more chelate rings with a metal in the molecule. That is, in addition to metal chelate compounds in which all coordination with the metal is formed by chelate rings, metal compounds having one or more chelate rings and an alkoxide are also included in the metal chelate compounds of the present invention. In addition, since the chelate rings remain in compounds (polymers) that have been dealcohol-condensed due to moisture in the air, such compounds are also included in the category of metal chelate compounds of the present invention.

Examples of compounds that form a chelate ring with a metal include β-diketone compounds, β-ketoester compounds, β-diester compounds, glycols, and triethanolamine. Among these, β-diketone compounds and β-ketoester compounds are preferred in terms of improving storage stability and ink receptivity of exposed areas. Examples of β-diketone compounds include acetylacetone, 1,3-diphenyl-1,3-propanedione, and 2,2,6,6-tetramethyl-3,5-heptanedione. Among these, acetylacetone is preferred in terms of increasing the metal concentration in the metal chelate compound obtained by coordination with the metal. As the β-ketoester compound, acetoacetic acid alkyl esters are preferred, and the number of carbon atoms in the alkyl portion is preferably 1 to 8. If the number of carbon atoms in the alkyl portion is 1 or more, the affinity with the silicone component can be improved. The number of carbon atoms in the alkyl portion is more preferably 2 or more. On the other hand, if the number of carbon atoms in the alkyl portion is 8 or less, the metal concentration in the metal chelate compound obtained by coordination with the metal can be increased. The number of carbon atoms in the alkyl portion is more preferably 6 or less.

Metals include aluminum (III), titanium (IV), manganese (II), manganese (III), iron (II), iron (III), cobalt (II), cobalt (III), nickel (II), nickel (IV), copper (I), copper (II), zinc (II), germanium (IV), indium (III), tin (II), tin (IV), zirconium (IV), hafnium (IV), etc. From the viewpoint of further improving storage stability and ink receptivity of exposed areas, trivalent or higher metals are preferred, and among these, aluminum, titanium, and zirconium are more preferred.

Examples of metal chelate compounds include aluminum tris acetylacetonate, di-methoxyaluminum monoacetylacetonate, diethoxyaluminum monoacetylacetonate, di-n-propoxyaluminum monoacetylacetonate, di-iso-propoxyaluminum monoacetylacetonate, di-n-butoxyaluminum monoacetylacetonate, di-sec-butoxyaluminum monoacetylacetonate, di-tert-butoxyaluminum monoacetylacetonate, aluminum tris ethylacetoacetate, di-methoxyaluminum monoethylacetoacetate, diethoxyaluminum monoethylacetoacetate, di-n-propoxyaluminum monoethylacetoacetate, di-iso-propoxyaluminum monoacetylacetonate, aluminum chelate compounds such as di-n-butoxyaluminum monoethyl acetoacetate, di-n-butoxyaluminum monoethyl acetoacetate, di-sec-butoxyaluminum monoethyl acetoacetate, and di-tert-butoxyaluminum monoethyl acetoacetate; titanium tetraacetylacetonate, di-methoxytitanium bisacetylacetonate, di-ethoxytitanium bisacetylacetonate, di-n-propoxytitanium bisacetylacetonate, di-iso-propoxytitanium bisacetylacetonate, di-n-butoxytitanium bisacetylacetonate, di-sec-butoxytitanium bisacetylacetonate, di-tert-butoxytitanium bisacetylacetonate; Titanium chelate compounds such as tetraethyl acetoacetate, di-methoxytitanium bisethyl acetoacetate, di-ethoxytitanium bisethyl acetoacetate, di-n-propoxytitanium bisethyl acetoacetate, di-iso-propoxytitanium bisethyl acetoacetate, di-n-butoxytitanium bisethyl acetoacetate, di-sec-butoxytitanium bisethyl acetoacetate, and di-tert-butoxytitanium bisethyl acetoacetate; zirconium tetraacetylacetonate, di-methoxyzirconium bisacetylacetonate, di-ethoxyzirconium bisacetylacetonate, di-n-propoxyzirconium bisacetylacetonate, and di-iso-propoxyzirconium bisacetylacetonate; Examples of zirconium chelate compounds include cetyl acetonate, di-n-butoxy zirconium bisacetylacetonate, di-sec-butoxy zirconium bisacetylacetonate, di-tert-butoxy zirconium bisacetylacetonate, zirconium tetraethyl acetoacetate, di-methoxy zirconium bisethyl acetoacetate, di-ethoxy zirconium bisethyl acetoacetate, di-n-propoxy zirconium bisethyl acetoacetate, di-iso-propoxy zirconium bisethyl acetoacetate, di-n-butoxy zirconium bisethyl acetoacetate, di-sec-butoxy zirconium bisethyl acetoacetate, and di-tert-butoxy zirconium bisethyl acetoacetate. Two or more of these may be included.

The metal concentration derived from the metal chelate compound in the metal chelate-containing silicone layer measured by X-ray photoelectron spectroscopy is 0.2 to 1.8 atom%. If the metal concentration derived from the metal chelate compound is less than 0.2 atom%, i.e., if there is a shortage of metal chelate compound, it becomes difficult to obtain the effect of changing the exposed area to ink-receptive property, resulting in insufficient ink-receptive property. The metal concentration derived from the metal chelate compound is more preferably 0.4 atom% or more, and even more preferably 0.6 atom% or more. On the other hand, if the metal concentration derived from the metal chelate compound exceeds 1.8 atom%, i.e., if there is an excess of metal chelate compound, the surface energy of the metal chelate-containing silicone layer increases and becomes weak, resulting in insufficient ink repellency and printing durability. The metal concentration derived from the metal chelate compound is more preferably 1.6 atom% or less, and even more preferably 1.4 atom% or less. The metal concentration derived from the metal chelate compound can be adjusted to the above range, for example, by adjusting the content of each component of the metal chelate-containing silicone layer to the preferred range described below.

As the metal chelate-containing silicone layer, a layer containing a metal chelate compound can be used in addition to the silicone layers of the addition reaction type, condensation reaction type, and combined addition reaction and condensation reaction type that have been disclosed so far as ink-repellent layers for waterless lithographic printing plates.

Examples of silicone layers of the addition reaction type, condensation reaction type, and combined addition reaction-condensation reaction type include layers exemplified as diorganosiloxane unit-containing layers in JP 2021-66175 A, layers exemplified as silicone rubber layers in WO 2019/203261, and layers exemplified as the first silicone layer in WO 2019/203263.

In the present invention, the element concentrations in the metal chelate-containing silicone layer are preferably silicon: 15.5 to 24.5 atom%, oxygen: 25.0 to 28.5 atom%, carbon: 50.0 to 57.0 atom%, and metal derived from metal chelate compound: 0.2 to 1.8 atom%, which can further improve ink receptivity, ink repellency, and printing durability. The element concentrations can be adjusted to the above ranges, for example, by adjusting the content of each component of the metal chelate-containing silicone layer to the preferred ranges described below.

The element concentrations in the metal chelate-containing silicone layer can be measured by X-ray photoelectron spectroscopy.

The average thickness of the metal chelate-containing silicone layer is preferably 5 μm or more. By making the average thickness of the metal chelate-containing silicone layer 5 μm or more, the ink repellency, scratch resistance, and printing durability of the printing plate can be further improved. On the other hand, the average thickness of the metal chelate-containing silicone layer is preferably 30 μm or less. The average thickness of the metal chelate-containing silicone layer can be determined by cross-sectional TEM observation. More specifically, a sample is prepared from the waterless lithographic printing plate precursor by ultra-thin sectioning, and TEM observation is performed under conditions of an acceleration voltage of 100 kV and a magnification of 2,000 times. In the TEM photograph of the vertical cross section, the thickness is measured at 10 randomly selected points from the metal chelate-containing silicone layer, and the average thickness can be calculated by calculating the number average value.

The waterless lithographic printing plate precursor of the present invention preferably further has a metal chelate-free silicone layer on the metal chelate-containing silicone layer. By having the metal chelate-free silicone layer, the ink repellency can be further improved. In the present invention, the metal chelate-free silicone layer refers to a silicone layer having a metal chelate compound content of less than 3% by mass.

As the metal chelate-free silicone layer, the aforementioned ink-repellent silicone layers of the addition reaction type, condensation reaction type, and combined addition reaction and condensation reaction type, which have been disclosed so far as ink-repellent layers for waterless lithographic printing plates, can be used.

The element concentration ratios in the metal chelate-free silicone layer are preferably silicon: 22-26 atom%, oxygen: 24-28 atom%, and carbon: 48-52 atom%, which can further improve ink repellency. The ratio of oxygen concentration to silicon concentration in the metal chelate-free silicone layer (oxygen concentration/silicon concentration) is preferably 0.9-1.2, which can further improve ink repellency. The element concentrations can be adjusted to the above ranges, for example, by adjusting the content of each component of the metal chelate-free silicone layer to the preferred ranges described below.

The element concentrations in the metal chelate-free silicone layer can be measured in the same manner as the element concentrations in the metal chelate-containing silicone layer. In addition, the ratio of the oxygen concentration to the silicon concentration (oxygen concentration/silicon concentration) can be calculated by dividing the obtained oxygen concentration value by the silicon concentration value.

The average thickness of the metal chelate-free silicone layer is preferably 0.1 μm or more. By making the average thickness of the metal chelate-free silicone layer 0.1 μm or more, the ink repellency can be further improved. 0.2 μm or more is more preferable. On the other hand, the average thickness of the metal chelate-free silicone layer is preferably 30 μm or less. The average thickness of the metal chelate-free silicone layer can be determined in the same manner as the average thickness of the metal chelate-containing silicone layer.

The waterless lithographic printing plate precursor of the present invention may have a primer layer between the support and the metal chelate-containing silicone layer, which can improve adhesion, plate inspection properties, scratch resistance, printing durability, etc.

Examples of the primer layer used in the waterless lithographic printing plate precursor of the present invention include the primer layers described as heat insulating layers in JP-A-2004-199016, JP-A-2004-334025, JP-A-2006-276385, etc.

The average thickness of the primer layer is preferably 0.2 to 30 μm.

The waterless lithographic printing plate precursor according to the present invention may have a cover film and/or an interleaf paper on the metal chelate-containing silicone layer or the metal chelate-free silicone rubber layer, which can protect the surface of the underlying silicone layer.

The cover film is preferably a film with a thickness of 100 μm or less. Specific examples include films made of polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, cellophane, etc.

The interleaf paper preferably has a basis weight of 30 to 90 g/m ^2. Examples of preferably used interleaf papers include information recording base paper 40 g/m ² (manufactured by Nagoya Pulp Co., Ltd.), metal interleaf paper 30 g/m ² (manufactured by Nagoya Pulp Co., Ltd.), unbleached kraft paper 50 g/m ² (manufactured by Chuetsu Pulp Co., Ltd.), NIP paper 52 g/m ² (manufactured by Chuetsu Pulp Co., Ltd.), pure white roll paper 45 g/m ² (manufactured by Oji Paper Co., Ltd.), Clupac 73 g/m ² (manufactured by Oji Paper Co., Ltd.), and the like.

Next, we will explain the method for producing the printing plate precursor according to the present invention.

The method for producing a printing plate precursor according to the present invention comprises at least
(1) continuously applying a metal chelate-containing silicone layer-forming composition onto a support; and
It is preferable to have a step of (2) curing the coating film obtained in the step (1) to form a metal chelate-containing silicone layer. The method for producing a printing plate precursor having a metal chelate-free silicone layer preferably further comprises the steps of:
(3) continuously applying a composition for forming a metal chelate-free silicone layer onto the coating film obtained in step (1) or the metal chelate-containing silicone layer obtained in step (2); and
It is preferable to have a step (4) of curing the coating film obtained in the step (3) to form a metal chelate-free silicone layer.

When a primer layer is provided between the support and the composition for forming a metal chelate-containing silicone layer, it is preferable to form the primer layer by applying the composition for forming a primer layer onto the support prior to step (1) and drying/curing the composition with or without heating.

Examples of methods for applying the composition for forming the primer layer include methods using a slit die coater, gravure coater, roll coater, wire bar coater, etc. Among these, application using a slit die coater is preferred.

When heating, examples of the heating device include a hot air dryer and an infrared dryer. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 30 seconds to 10 minutes.

In step (1), it is preferable to coat the entire surface of the support with the metal chelate-containing silicone layer-forming composition described below. When a primer layer is present between the support and the metal chelate-containing silicone layer-forming composition, it is preferable to coat the metal chelate-containing silicone layer-forming composition described below on the primer layer formed on the support. When coating, it is preferable to remove as much moisture as possible from the support surface and the primer layer surface in order to improve adhesion.

Methods for applying the composition for forming the metal chelate-containing silicone layer include the methods exemplified as the application methods for the composition for forming the primer layer, and application with a slit die coater is preferred.

In step (2), it is preferable to cure by heating. The preferred heating conditions are the same as those for the primer layer.

In step (3), it is preferable to coat the metal chelate-free silicone layer-forming composition on the entire surface of the metal chelate-containing silicone layer. The metal chelate-free silicone layer-forming composition is preferably a composition obtained by removing the metal chelate compound from the metal chelate-containing silicone layer-forming composition described below. Examples of coating methods include the methods exemplified as coating methods for the primer layer-forming composition, and slit die coater coating is preferable.

In step (4), it is preferable to cure by heating. The preferred heating conditions are the same as those for the primer layer.

Next, a metal chelate-containing silicone layer-forming composition suitable for use in the method for producing a printing plate precursor according to the present invention will be described. The metal chelate-containing silicone layer-forming composition according to the present invention contains a polysiloxane having two or more silanol groups or vinyl groups in the molecule, a crosslinking agent having three or more functional groups in the molecule that are reactive with the silanol groups or vinyl groups, and a metal chelate compound having one or more chelate rings in the molecule.

Examples of metal chelate compounds include those exemplified in the printing plate precursor, and preferred embodiments thereof are the same as those in the printing plate precursor.

The content of the metal chelate compound in the composition for forming a metal chelate-containing silicone layer is preferably 3% by mass or more of the total solid content, and the metal concentration derived from the metal chelate can be easily adjusted to the preferred range described above, thereby further improving the ink receptivity of the exposed area. 7% by mass or more is more preferable, and 10% by mass or more is even more preferable. On the other hand, the content of the metal chelate compound is preferably 38% by mass or less of the total solid content, and the metal concentration derived from the metal chelate can be easily adjusted to the preferred range described above, thereby further improving the ink repellency and printing durability of the unexposed area. 34% by mass or less is more preferable, and 30% by mass or less is even more preferable.

Here, the total solid content of the metal chelate-containing silicone layer-forming composition refers to all components of the metal chelate-containing silicone layer-forming composition excluding the solvent.

A composition for forming a metal chelate-containing silicone layer, which contains a metal chelate compound, a polysiloxane having two or more vinyl groups in the molecule, and a crosslinking agent having three or more functional groups in the molecule that are reactive with vinyl groups, is an addition reaction type composition for forming a metal chelate-containing silicone layer. It preferably contains a siloxane compound having three or more SiH groups in the molecule as a crosslinking agent, and contains a reaction catalyst. It may further contain a reaction inhibitor or a silane coupling agent.

The composition for forming a metal chelate-containing silicone layer, which contains a metal chelate compound, a polysiloxane having two or more silanol groups in the molecule, and a crosslinking agent having three or more functional groups in the molecule that are reactive with silanol groups, is a condensation reaction type metal chelate-containing silicone layer composition, which preferably contains a silane coupling agent having three or more hydrolyzable groups in the molecule as a crosslinking agent, and a reaction catalyst.

A composition for forming a metal chelate-containing silicone layer, which contains a metal chelate compound, a polysiloxane having two or more silanol groups in the molecule, a silane coupling agent having three or more functional groups in the molecule that are reactive with silanol groups and one or more vinyl groups in the molecule, and a crosslinking agent having three or more functional groups in the molecule that are reactive with vinyl groups, is a composition for forming a metal chelate-containing silicone layer of a combined addition reaction-condensation reaction type. It preferably contains a siloxane compound having three or more SiH groups in the molecule as a crosslinking agent, and contains a reaction catalyst. It may further contain a reaction inhibitor or a silane coupling agent other than the above.

First, we will explain the addition reaction type metal chelate-containing silicone layer forming composition.

Examples of polysiloxanes having two or more vinyl groups in the molecule include diorganopolysiloxanes having vinyl groups at both molecular terminals, organovinylpolysiloxanes, organovinylsiloxane-diorganosiloxane copolymers, and polysiloxanes having two or more diorganovinylsiloxy groups in the molecule. Two or more of these may be contained. Among these, diorganopolysiloxanes having vinyl groups at both molecular terminals, and organovinylsiloxane-diorganosiloxane copolymers are preferred.

Diorganopolysiloxanes and organovinylsiloxane-diorganosiloxane copolymers having vinyl groups at both ends of the molecule may have any of linear, cyclic, branched, and network molecular structures. The organic groups bonded to silicon atoms may be the same or different in each repeating unit, and each is a monovalent organic group that does not contain an aliphatic unsaturated bond. Examples of monovalent organic groups that do not contain an aliphatic unsaturated bond include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl and phenethyl; and halogenated alkyl groups such as chloromethyl, 3-chloropropyl, and 3,3,3-trifluoropropyl.

It is preferable that 50 mol % or more of the monovalent organic groups not containing aliphatic unsaturated bonds are methyl groups in order to further improve ink repellency. In addition, the weight average molecular weight of the polysiloxane having two or more vinyl groups in the molecule is preferably 30,000 or more in order to further improve printing durability and scratch resistance, and is preferably 300,000 or less in order to improve coating properties. The weight average molecular weight is a polystyrene-equivalent value measured using GPC.

The content of polysiloxane having two or more vinyl groups in the molecule in the composition for forming a metal chelate-containing silicone layer is preferably 60% by mass or more of the total solid content, so that the element concentration can be easily adjusted to the above-mentioned preferred range and the ink repellency can be further improved. 65% by mass or more is more preferable, and 70% by mass or more is even more preferable. On the other hand, the content of polysiloxane having two or more vinyl groups in the molecule is preferably 95% by mass or less of the total solid content, so that the element concentration can be easily adjusted to the above-mentioned preferred range and the ink receptivity of the metal chelate-containing silicone layer can be further improved. 90% by mass or less is more preferable, and 85% by mass or less is even more preferable.

Examples of siloxane compounds having three or more SiH groups in the molecule include organohydropolysiloxanes, organohydrosiloxane-diorganosiloxane copolymers, and compounds having three or more diorganohydrosiloxy groups in the molecule. Two or more of these may be contained. Among these, organohydropolysiloxanes and organohydrosiloxane-diorganosiloxane copolymers are preferred. The number of SiH groups in the molecule is preferably 5 or more, more preferably 6 or more, in order to improve the curing properties of the metal chelate-containing silicone layer.

The organohydropolysiloxane and organohydrosiloxane-diorganosiloxane copolymer may have any of linear, cyclic, branched, and network molecular structures. The organic groups bonded to the silicon atoms may be the same or different in each repeating unit, and each is a monovalent organic group that does not contain an aliphatic unsaturated bond. Examples of monovalent organic groups that do not contain an aliphatic unsaturated bond include the groups exemplified in the diorganopolysiloxane and organovinylsiloxane-diorganosiloxane copolymer that have vinyl groups at both molecular terminals.

The content of the siloxane compound having three or more SiH groups in the molecule in the composition for forming the metal chelate-containing silicone layer is preferably 0.5% by mass or more in the total solid content, and the element concentration can be easily adjusted to the above-mentioned preferred range to improve the curing property of the metal chelate-containing silicone layer. 1% by mass or more is more preferable. On the other hand, the content of the siloxane compound having three or more SiH groups in the molecule is preferably 10% by mass or less in the total solid content, and the element concentration can be easily adjusted to the above-mentioned preferred range to further improve the ink repellency. 5% by mass or less is more preferable.

The reaction catalyst is preferably one containing platinum or rhodium. Examples of the reaction catalyst containing platinum include platinum alone, solid platinum supported on a carrier (alumina, silica, carbon black, etc.), chloroplatinic acid, platinum-olefin complex, platinum-vinylsilane complex, platinum-vinylsiloxane complex, platinum-phosphine complex, platinum-phosphite complex, platinum-acetylacetone complex, platinum-alkyl acetoacetate complex, platinum-dialkyl malonate complex, platinum-hydrocarbon complex described in U.S. Pat. Nos. 3,159,601 and 3,159,662, and platinum alcoholate catalyst described in U.S. Pat. No. 3,220,972. _Examples of reaction catalysts other than platinum compounds include RhCl( _PPh3 ) ₃ , _RhCl3 , _RhAl2O3 , _RuCl3 , _IrCl3 , _FeCl3 , _AlCl3 , _PdCl2.2H2O , _NiCl2 , _TiCl4 , _etc. Two or more of these may be contained.

The content of the reaction catalyst in the composition for forming the metal chelate-containing silicone layer is preferably 0.001% by mass or more and 0.1% by mass or less of the total solid content.

As the reaction inhibitor, an amine compound or an acetylene compound is preferable, and examples thereof include pyridine, picoline, 2,2'-dipyridyl, 2-butanone oxime, acetylene alcohol, and acetylene silane. Examples of acetylene alcohol include 2-methyl-3-butyn-2-ol, 2-phenyl-3-butyn-2-ol, 1-ethynyl-1-hexanol, 3,5-dimethyl-1-hexyn-3-ol, and 3-methyl-1-pentyn-3-ol. Two or more of these may be contained. By containing these reaction inhibitors, the pot life of the metal chelate-containing silicone layer-forming composition is improved.

The content of the reaction inhibitor in the composition for forming the metal chelate-containing silicone layer is preferably 0.1 parts by mass or more and 15 parts by mass or less based on the total solid content.

Preferred silane coupling agents are vinyltriacetoxysilane and vinyltris(methylethylketoximino)silane.

The content of the silane coupling agent in the composition for forming the metal chelate-containing silicone layer is preferably 1% by mass or more and 5% by mass or less of the total solid content.

Next, we will explain the composition for forming a condensation reaction type metal chelate-containing silicone layer.

An example of a polysiloxane having two or more silanol groups in a molecule is a diorganopolysiloxane having silanol groups at both ends of the molecule.

Diorganopolysiloxanes having silanol groups at both molecular terminals may have any of linear, cyclic, branched, and network molecular structures. The organic groups bonded to silicon atoms may be the same or different in each repeating unit, and each is a monovalent organic group that does not contain an aliphatic unsaturated bond. Examples of monovalent organic groups that do not contain an aliphatic unsaturated bond include the groups exemplified in diorganopolysiloxanes having vinyl groups at both molecular terminals and organovinylsiloxane-diorganosiloxane copolymers.

It is preferable that 50 mol % or more of the monovalent organic groups not containing aliphatic unsaturated bonds are methyl groups in order to further improve ink repellency. In addition, the weight average molecular weight of the polysiloxane having two or more silanol groups in the molecule is preferably 30,000 or more in order to further improve printing durability and scratch resistance, and is preferably 300,000 or less in order to improve coating properties. The weight average molecular weight is a polystyrene-equivalent value measured using GPC.

The content of polysiloxane having two or more silanol groups in the molecule in the composition for forming a metal chelate-containing silicone layer is preferably 60% by mass or more in the total solid content, so that the element concentration can be easily adjusted to the above-mentioned preferred range and the ink repellency can be further improved. 65% by mass or more is more preferable, and 70% by mass or more is even more preferable. On the other hand, the content of polysiloxane having two or more silanol groups in the molecule is preferably 95% by mass or less in the total solid content, so that the element concentration can be easily adjusted to the above-mentioned preferred range and the ink receptivity of the metal chelate-containing silicone layer can be further improved. 90% by mass or less is more preferable, and 85% by mass or less is even more preferable.

Examples of crosslinking agents having three or more functional groups in the molecule that are reactive with silanol groups include silane coupling agents, and examples of silane coupling agents include the silane coupling agents exemplified in the composition for forming an addition reaction type metal chelate-containing silicone layer.

The content of the silane coupling agent in the composition for forming a metal chelate-containing silicone layer is preferably 0.5% by mass or more of the total solid content, which can improve curability and adhesion to the lower layer. 1% by mass or more is more preferable. On the other hand, the content of the silane coupling agent in the composition for forming a metal chelate-containing silicone layer is preferably 10% by mass or less of the total solid content, which can further improve ink repellency. 5% by mass or less is more preferable.

Examples of reaction catalysts include organic carboxylic acids, acids, alkalis, amines, metal alkoxides, metal diketenates, and organic acid salts of metals such as tin, lead, zinc, iron, cobalt, calcium, and manganese. More specific examples include dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, zinc octylate, and iron octylate. Two or more of these may be contained.

The content of the reaction catalyst in the composition for forming the metal chelate-containing silicone layer is preferably 0.01% by mass or more and 1% by mass or less of the total solid content.

Next, we will explain the addition reaction-condensation reaction type metal chelate-containing silicone layer forming composition.

Examples of polysiloxanes having two or more silanol groups in the molecule include the polysiloxanes exemplified in the composition for forming a condensation reaction type metal chelate-containing silicone layer. The preferred range of the content of polysiloxanes having two or more silanol groups in the composition for forming a metal chelate-containing silicone layer is the same as that of the composition for forming a condensation reaction type metal chelate-containing silicone layer.

Examples of crosslinking agents having three or more functional groups in the molecule that are reactive with silanol groups include silane coupling agents, and examples of silane coupling agents include the silane coupling agents exemplified in the addition reaction type metal chelate-containing silicone layer forming composition. The preferred range of the content of the crosslinking agent having three or more functional groups in the molecule that are reactive with silanol groups in the metal chelate-containing silicone layer forming composition is the same as that of the condensation reaction type metal chelate-containing silicone layer forming composition.

Examples of silane coupling agents having one or more vinyl groups in the molecule include the silane coupling agents exemplified in the composition for forming an addition reaction type metal chelate-containing silicone layer.

The content of the silane coupling agent having one or more vinyl groups in the molecule in the composition for forming the metal chelate-containing silicone layer is preferably 1% by mass or more and 5% by mass or less of the total solid content.

Examples of siloxane compounds having three or more SiH groups in the molecule include the siloxane compounds exemplified in the composition for forming a metal chelate-containing silicone layer of the addition reaction type. The preferred range of the content of the siloxane compounds having three or more SiH groups in the composition for forming a metal chelate-containing silicone layer is the same as that of the composition for forming a metal chelate-containing silicone layer of the addition reaction type.

Examples of reaction catalysts include the reaction catalysts exemplified in the composition for forming an addition reaction type metal chelate-containing silicone layer. The preferred range of the content of the reaction catalyst in the composition for forming a metal chelate-containing silicone layer is the same as that in the composition for forming an addition reaction type metal chelate-containing silicone layer.

Examples of reaction inhibitors include the reaction inhibitors exemplified in the composition for forming an addition reaction type metal chelate-containing silicone layer. The preferred range of the content of the reaction inhibitor in the composition for forming a metal chelate-containing silicone layer is the same as that in the composition for forming an addition reaction type metal chelate-containing silicone layer.

The metal chelate-containing silicone layer-forming composition may also contain a liquid having a surface tension of 30 mN/m or less at 25°C, which can further improve ink repellency. Examples of liquids having a surface tension of 30 mN/m or less at 25°C include liquids described in WO 2016/076286 and the like.

The metal chelate-containing silicone layer-forming composition may also contain known reinforcing agents, such as silica particles or silicone resins having functional groups such as vinyl groups, SiH groups, and silanol groups, to improve the rubber strength.

It is preferable that the composition for forming the metal chelate-containing silicone layer contains a solvent, which can improve the coatability and the solubility and compatibility of the metal chelate compound.

Examples of the solvent include aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, aromatic hydrocarbon solvents, halogenated hydrocarbons, and linear or cyclic ether compounds. In order to improve the solubility, compatibility, and coatability of the silicone component, it is preferable to include an aliphatic hydrocarbon solvent and/or an alicyclic hydrocarbon solvent. On the other hand, in order to improve the solubility and compatibility of the metal chelate compound, it is preferable to include an aromatic hydrocarbon solvent. That is, in order to be able to dissolve or be compatible with both the silicone component and the metal chelate compound and to have excellent coatability, it is preferable to use a mixed solvent of an aliphatic hydrocarbon solvent and/or an alicyclic hydrocarbon solvent and an aromatic hydrocarbon solvent. In order to improve coatability, the proportion of the aromatic hydrocarbon solvent in the mixed solvent is preferably 30% by volume or less, more preferably 25% by volume or less. In addition, in order to improve safety and ease of handling, the boiling point of the above solvent at 1 atmosphere is preferably 60°C or more, more preferably 80°C or more. On the other hand, in order to improve the drying property of the coating liquid, the boiling point of the above solvent at 1 atmosphere is preferably 160°C or less, more preferably 140°C or less. Examples of such solvents include linear or branched aliphatic hydrocarbon solvents having 6 to 9 carbon atoms, alicyclic hydrocarbon solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, and trimethylcyclohexane, and aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, and diethylbenzene. Two or more of these may be included. Commercially available solvents such as those listed below may also be used.

Aliphatic hydrocarbon solvent mixtures: For example, Marukasol 8 (manufactured by Maruzen Petrochemical Co., Ltd.), "Isopar" (registered trademark) C, "Isopar" (registered trademark) E (all manufactured by ExxonMobil Chemical Co.), IP Solvent 1016 (manufactured by Idemitsu Kosan Co., Ltd.), "Isosol" (registered trademark) 200 (manufactured by JX Nippon Oil & Energy Corporation), etc. are available from each company.

Alicyclic hydrocarbon solvent mixtures: For example, "EXXSOL" (registered trademark) DSP 80/100, "EXXSOL" DSP 100/140, "EXXSOL" DSP 145/160 (all manufactured by ExxonMobil Chemical Corporation), CS volatile oil (manufactured by JX Nippon Oil & Energy Corporation), etc. are available from various companies.

The specific method for preparing the composition for forming the metal chelate-containing silicone layer is described below, but is not limited to this.

For example, a solvent, a siloxane compound having two or more vinyl groups in its molecule, and a liquid having a surface tension of 30 mN/m or less at 25°C are added to a container and stirred until the components are uniform, and then the water in the solution is removed by blowing dry nitrogen. Next, a reaction catalyst and a reaction inhibitor are added and stirred until the components are uniform, and then a siloxane compound having three or more SiH groups in its molecule and a silane coupling agent are added and stirred until the components are uniform. Finally, a metal chelate compound is added and stirred until the components are uniform, thereby obtaining a composition for forming a metal chelate-containing silicone layer.

Examples of compositions for forming a primer layer include compositions described as compositions for forming a heat insulating layer in, for example, JP-A-2004-199016, JP-A-2004-334025, and JP-A-2006-276385.

Next, a method for producing a lithographic printing plate from a lithographic printing plate precursor will be described. In the method for producing a lithographic printing plate according to the present invention, the lithographic printing plate precursor according to the present invention described above is exposed to active energy rays from the metal chelate-containing silicone layer side or the metal chelate-free silicone layer side to form an ink-receiving portion.

If a cover film or interleaf paper is provided on the metal chelate-containing silicone layer or the metal chelate-free silicone layer of the lithographic printing plate precursor, it is preferable to remove these beforehand.

By exposing the metal chelate-containing silicone layer or metal chelate-free silicone layer of the above-mentioned lithographic printing plate precursor to active energy rays in a pattern, the metal chelate-containing silicone layer or metal chelate-free silicone layer in the exposed area changes to ink-receptive property. The peak wavelength of the active energy rays is preferably 200 to 600 nm. If the peak wavelength is 200 nm or more, exposure in a nitrogen atmosphere or vacuum is not necessary, and exposure can be performed in the atmosphere. On the other hand, if the peak wavelength is 600 nm or less, the ink-receptive property of the exposed area can be further improved. A peak wavelength of 400 nm or less is more preferable. Since a mask for plate making is not required, it is preferable to directly draw the pattern of the ink-receptive area using a laser drawing device with a wavelength of 200 to 600 nm.

Examples of active energy ray exposure devices with a wavelength of 200 to 600 nm include low pressure mercury lamps, high pressure mercury lamps, metal halide lamps, and excimer lamps, each of which has a peak wavelength in the range of 200 to 600 nm. Examples of excimer lamps with a wavelength of 200 to 600 nm include rare gas excimer lamps and rare gas halogen excimer lamps, such as KrBr (207 nm), KrCl (222 nm), KrF (248 nm), XeI (253 nm), HgXe (254 nm), Cl ₂ (259 nm), XeBr (283 nm), XeCl (308 nm), I ₂ (342 nm), XeF (352 nm), HgI (443 nm), HgBr (503 nm), and HgCl (558 nm). Among these, from the viewpoint of improving the productivity of lithographic printing plates, ultraviolet excimer lamps with wavelengths of 200 to 400 nm, such as KrBr (207 nm), KrCl (222 nm), KrF (248 nm), XeI (253 nm), HgXe (254 nm), Cl ₂ (259 nm), XeBr (283 nm), XeCl (308 nm), I ₂ (342 nm), and XeF (352 nm), are more preferred.

Examples of active energy ray lasers with a wavelength of 200 to 600 nm include the fifth harmonic (213 nm) of an Nd:YAG laser or an Nd: _YVO4 laser, the fourth harmonic (266 nm) of an Nd: _YAG laser or an Nd:YVO4 laser, the third harmonic (355 nm) of an Nd:YAG laser or an Nd: _YVO4 laser, and the third harmonic (355 nm) of an Nd:YAG laser or an Nd:YVO4 laser. Examples of such lasers include solid-state lasers such as the second harmonic of the I.O.S. No. ₄ laser (532 nm), the third harmonic of the ruby laser (231 nm), the second harmonic of the ruby laser (347 nm), the third harmonic of the alexandrite laser (252 nm), and the second harmonic of the alexandrite laser (378 nm), as well as rare gas excimer lasers and rare gas halogen excimer lasers such as the KrBr laser (207 nm), KrCl laser (222 nm), _KrF laser (248 nm), XeI laser (253 nm), HgXe laser (254 nm), _Cl2 laser (259 nm), XeBr laser (283 nm), XeCl laser (308 nm), I2 laser (342 nm), XeF laser (352 nm), HgI laser (443 nm), HgBr laser (503 nm), and HgCl laser (558 nm). Among these, in terms of improving the productivity of lithographic printing plates, the fifth harmonic (213 nm) of the Nd:YAG laser or Nd: _YVO4 laser, the fourth harmonic (266 nm) of the Nd:YAG laser or Nd: _YVO4 laser, the third harmonic (355 nm) of the Nd:YAG laser or Nd: _YVO4 laser, the third harmonic (231 nm) of the ruby laser, the second harmonic (347 nm) of the ruby laser, the third harmonic (252 nm) of the alexandrite laser, the second harmonic (378 nm) of the alexandrite laser, KrBr laser (207 nm), KrCl laser (222 nm), KrF laser (248 nm), XeI laser (253 nm), HgXe laser (254 nm), _Cl2 laser (259 nm), XeBr laser (283 nm), XeCl laser (308 nm), I More preferred are ultraviolet lasers with a wavelength of 200 to 400 nm, such as the Fluorine _-2 laser (342 nm) and the XeF laser (352 nm).

The preferred oscillation method for the active energy ray laser is the pulse oscillation method. In addition, the pulse width of the pulse laser can be any pulse width of nanoseconds, picoseconds, or femtoseconds. Among these, the nanosecond pulse laser is preferred because it has a relatively small thermal load and is less susceptible to ablation due to multiphoton absorption.

In this invention, a laser refers to an electromagnetic wave amplified in a resonator.

The exposure dose of active energy rays having a wavelength of 200 to 600 nm is preferably 2 J/ ^cm2 or more, and more preferably 3 J/ ^cm2 or more, from the viewpoint of further improving the ink receptivity of the exposed area. On the other hand, the exposure dose is preferably 8 J/cm2 or ^less , more preferably 7 J/ ^cm2 or less, and even more preferably 6 J/cm2 or ^less , from the viewpoint of further suppressing ablation dust in the exposed area.

In the present invention, the exposure dose E is calculated by the following formula, and the irradiation energy [W] can be measured using a commercially available power meter or the like.
<How to determine the exposure amount E>
E=W÷S×T [J/ ^cm2 ]
W: Irradiation energy [W]
S: Irradiation area [cm ² ]
T: Irradiation time [sec].

When the resulting lithographic printing plates are stacked for storage, it is preferable to laminate interleaf paper between the lithographic printing plates, which can protect the top surface of the lithographic printing plates.

Next, we will explain the manufacturing method for printed matter.

The method for producing a printed matter preferably uses the waterless lithographic printing plate, ink, and print medium described above. Specifically, the method preferably includes a step of applying ink to the surface of the inked portion of the waterless lithographic printing plate, and a step of transferring the ink applied to the surface of the inked portion to the print medium, either directly or via a blanket.

As the printing machine, a known direct printing machine or offset printing machine can be used, but an offset printing machine is preferred because it can produce more printed matter by minimizing damage to the waterless lithographic printing plate during printing.

As for offset printing machines, offset printing machines equipped with a cooling mechanism for the oscillating roller and/or plate cylinder are preferred in terms of improving the resistance to scumming.

As the ink, known oxidative polymerization inks and active energy ray curable inks can be used, but active energy ray curable inks are preferred because they dry quickly and allow the next step to be carried out immediately after printing. Ink may be either oil-soluble or water-soluble, but water-soluble inks are preferred in terms of reducing the burden on workers and the environment. Water-soluble active energy ray curable inks are more preferred.

As the active energy rays, those exemplified in the method for producing a lithographic printing plate are preferred.

Examples of water-soluble active energy beam-curable inks that are preferably used in the present invention include known water-soluble active energy beam-curable inks that can be washed with water or a water-based cleaning solution, such as those disclosed in JP 2017-52817 A, WO 2017/047817 A, and WO 2017/090663 A.

Printing media include papers such as fine paper, art paper, coated paper, cast paper, synthetic paper, and newsprint; metals such as aluminum, aluminum alloys, iron, steel, zinc, and copper; plastic films such as polyethylene terephthalate, polyethylene, polyester, polyamide, polyimide, polystyrene, polypropylene, polycarbonate, and polyvinyl acetal; and composites of these papers, metals, and plastic films (paper or plastic film vapor-deposited or laminated with metal, paper or metal laminated with plastic film, and metal or plastic film laminated with paper).

In particular, the method for producing printed matter according to the present invention is suitable for printing on print media that do not absorb ink components, such as synthetic paper, metals, plastic films, paper or plastic film on which metal is vapor-deposited or laminated, and paper or metal laminated with a plastic film, whose print surface is made of metal or plastic film.

Of the above, the printing surface of the printing medium, such as synthetic paper, plastic films, paper laminated with plastic film, or metal, whose printing surface is made of plastic film, may be subjected to surface treatment such as application of a primer resin, corona discharge treatment, or plasma treatment to improve adhesion.

It is preferable to use a roll of long print medium as the shape of the print medium. By printing using the waterless lithographic printing plate of the present invention and a roll of long print medium by the roll-to-roll method, it is possible to mass-produce high-definition prints with seamless picture patterns.

The waterless lithographic printing plate of the present invention does not require a development process, and there is no need to use pre-treatment chemicals or post-treatment chemicals used in conventional development processes. Therefore, pre-treatment chemicals and post-treatment chemicals do not adhere to or penetrate the waterless lithographic printing plate, and these chemicals do not migrate from the waterless lithographic printing plate to the printed matter during the printing process, making it particularly suitable for use in printing for food packaging applications, which have strict chemical content requirements.

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

Evaluation of each example and comparative example was carried out using the following methods.

(1) Evaluation of waterless lithographic printing plates (1-1) Elemental concentrations in metal chelate-containing silicone layer and metal chelate-free silicone layer For the metal chelate-containing silicone layer and the metal chelate-free silicone layer of the waterless lithographic printing plate precursors obtained in each Example and Comparative Example, the elemental concentration (atom %) was calculated from the area ratio of each elemental spectrum detected by X-ray photoelectron spectroscopy. The analytical conditions are shown below.
[Analysis conditions]
Analytical device: ESCA system ULVAC-PHI5700 (manufactured by ULVAC-PHI)
Degree of vacuum: 5.0×10 ⁻⁷ Torr or less X-ray source: Mg source Acceleration voltage: 15 kV
Number of times of accumulation: 6 Measurement step: 0.125 eV
Scan: narrow scan X-ray incident angle: 45 degrees [analysis conditions]
Data analysis software: PHI MultiPak (ULVAC-PHI)
Smoothing correction: Point 9
Background correction: OFF SET.

(1-2) Average excavation amount of exposed area Five exposed and unexposed areas were randomly selected from the waterless planographic printing plates obtained in each Example and Comparative Example, and the height difference between the exposed and unexposed areas was calculated from the height information of the exposed and unexposed areas measured by a 3D measuring laser microscope, and this was taken as the excavation amount of the exposed area. The average value of the five obtained excavation amounts was taken as the average excavation amount of exposed area (μm), and the likelihood of ablation dust generation was evaluated based on the average excavation amount of exposed area. It can be said that the smaller the average excavation amount of exposed area, the less ablation dust is generated during exposure. The analysis conditions and analysis conditions are shown below.
[Analysis conditions]
Analytical device: LEXT OLS4100 (Olympus Corporation)
Analysis mode: High-precision mode Laser wavelength: 405 nm
Laser spot diameter: 200 nm
Objective lens magnification: 50x Measurement range: 259 x 259 [μm].
[Analysis conditions]
Image analysis software: OLS4100 (Olympus Corporation)
Noise correction: sawtooth surface noise removal.

(2) Printing Evaluation (2-1) Ink Repellency/Ink Receptivity The waterless lithographic printing plates obtained in each of the Examples and Comparative Examples were mounted on the plate cylinder (plate cylinder shaft for Examples 44 and 45) of an EB offset printing machine: OFFSET CI/8 (manufactured by COMEXI), and printing was carried out under the printing conditions shown below using a commercially available waterless lithographic printing plate precursor: Toray Waterless CTP Lithographic Plate TAC-VG5, which was made under standard conditions, as a reference.
[Printing conditions]
Ink roller: #8000 (manufactured by Meiwa Rubber Industries Co., Ltd.)
Cylindrical blanket: EPDM blanket (manufactured by Kinyosha Co., Ltd.)
Water-soluble EB ink: Offset EB ink F type FE1908 red (manufactured by Mitsuboshi Ink Co., Ltd.)
Ink component non-absorbent print medium: "EMBLET" (registered trademark) PTM-12 (rolled biaxially stretched PET film, thickness: 12 μm, printing surface: easy-adhesion treatment, manufactured by Unitika Ltd.)
Plate surface temperature: 25-28℃
Printing speed: 100 m/min. Ink supply amount: Three levels in which the reflection density of the solid part of the printed matter printed with TAC-VG5 falls within the ranges of (1) 1.20±0.02, (2) 1.50±0.02, and (3) 1.80±0.02 [Ink curing conditions]
EB irradiation dose: 40kGy
EB irradiation atmosphere: nitrogen atmosphere.

The prints printed at 500 m from the start of printing, each printed at the three different ink supply rates, were placed on top of five sheets of coated paper: OK "Topcoat" (registered trademark) + (Oji Paper Co., Ltd.), and the reflection density of the white solid area and the solid area was measured using a spectrodensitometer/colorimeter: Exact Advance (X-Rite).

Ink repellency was evaluated based on the reflection density of the solid white area. The lower the reflection density of the solid white area, the better the ink repellency. Ink adhesion was evaluated based on the reflection density of the solid area. The more the reflection density of the solid area is equal to or higher than that of the solid area of TAC-VG5, the better the ink adhesion.

(2-2) Printing durability Printing was performed up to 100,000 m under the above printing conditions (VG5 solid reflection density: 1.50±0.05), and printed matter was sampled every 5,000 m to evaluate the presence or absence of background scumming, which is the formation of unintended print lines in non-printed areas. The limit printing length at which good prints could continue to be obtained was evaluated as printing durability. The longer the limit printing length, the better the printing durability.

In addition, since comparative examples 3, 4, and 9 did not produce good prints even at the initial printing stage, the limit printing length at which prints of the same quality as at the initial printing stage continued to be produced was evaluated as printing durability.

[Example 1]
The following composition for forming a primer layer was applied onto an aluminum alloy plate having a thickness of 0.24 mm using a slit die coater (manufactured by Toray Engineering Co., Ltd.), and heated at 180°C for 2 minutes to provide a primer layer having an average thickness of 10 µm.

<Composition for forming primer layer>
The following components (a-1), (b-1), and (c-1) were added to a container and stirred and mixed until component (c-1) was dissolved. Components (d-1) and (e-1) were added to the resulting solution and stirred and mixed until the components were uniform, thereby obtaining a composition for forming a primer layer.
(a-1) N,N-dimethylformamide: 270.00 parts by mass (b-1) methyl ethyl ketone: 210.00 parts by mass (c-1) epoxy resin: "jER" (registered trademark) 1010 (manufactured by Mitsubishi Chemical Corporation): 35.00 parts by mass (d-1) polyurethane: "Sanprene" (registered trademark) LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., solid content: 20% by mass): 265.00 parts by mass (e-1) crosslinking agent: "Duranate" (registered trademark) MF-B60B (manufactured by Asahi Chemical Industry Co., Ltd., HDI-based blocked isocyanate, solid content: 60% by mass (solvent: n-butyl acetate/n-butanol)): 20.00 parts by mass.

Next, the following metal chelate-containing silicone layer-forming composition-1 was applied onto the primer layer using a slit die coater and heated at 100°C for 1 minute to provide a metal chelate-containing silicone layer (first layer) with an average thickness of 20 μm, thereby obtaining a waterless lithographic printing plate precursor.

<Metal chelate-containing silicone layer-forming composition-1>
The following components (f-1), (g-1) and (h-1) were added to a container and stirred and mixed until component (h-1) was dissolved. Components (i-1) and (j-1) were added to the resulting solution and stirred and mixed for 10 minutes, after which component (k-1) was added and stirred and mixed for 10 minutes. Finally, component (l-1) was added and stirred and mixed for 10 minutes, yielding metal chelate-containing silicone layer-forming composition-1.
(f-1) Naphthene-based solvent: "Exxol" (registered trademark) DSP100/140 (manufactured by ExxonMobil Chemical Company): 240.00 parts by mass (g-1) Aromatic hydrocarbon-based solvent: Toluene: 60.00 parts by mass (h-1) Siloxane compound having two or more vinyl groups in the molecule (dimethylvinylsiloxy-polydimethylsiloxane at both ends): DMS-V42 (GELEST (i-1) Reaction catalyst (platinum mixture): XC94-C4326 (manufactured by Momentive Performance Materials Japan, LLC, solid content concentration: 1% by mass): 3.00 parts by mass (j-1) Reaction inhibitor: 2-methyl-3-butyn-2-ol: 0.20 parts by mass (k-1) Siloxane compound having three or more SiH groups in the molecule (both terminal trimethylsiloxy-polymethylhydrosiloxane): HMS-993 (manufactured by GELEST Inc., weight average molecular weight: 2,250, number of SiH groups in the molecule: 34.8): 2.50 parts by mass (l-1) Metal chelate compound: AL-A (W) (manufactured by Kawaken Fine Chemical Co., Ltd., aluminum trisacetylacetonate): 12.37 parts by mass.

A pattern was drawn on the metal chelate-containing silicone layer of the waterless lithographic printing plate precursor in air with an exposure dose of 5 J/ ^cm2 using a solid pulse laser with a wavelength of 355 nm: 3-Axis UV Laser Marker MD-U1000C (manufactured by Keyence Corporation), to obtain a waterless lithographic printing plate.

[Example 2]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-2) a metal chelate compound: ALCH-TR (manufactured by Kawaken Fine Chemicals Co., Ltd., aluminum trisethylacetoacetate): 15.81 parts by mass.

[Example 3]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-3) a metal chelate compound: ALCH (manufactured by Kawaken Fine Chemicals Co., Ltd., di-iso-propoxide aluminum monoethyl acetoacetate): 10.47 parts by mass.

[Example 4]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-4) a metal chelate compound: "ORGATIXX" (registered trademark) TC-401 (manufactured by Matsumoto Fine Chemical Co., Ltd., a titanium tetraacetylacetonate/2-propanol = 65/35 mass % solution) was replaced with 16.95 parts by mass of a compound obtained by removing the solvent by blowing dry nitrogen.

[Example 5]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-5) a metal chelate compound: "ORGATIXX" (registered trademark) TC-150 (manufactured by Matsumoto Fine Chemical Co., Ltd., a solution of di-n-butoxide titanium bisacetylacetonate/n-butanol = 73/27 mass %) was replaced with 14.97 parts by mass of a compound obtained by removing the solvent by blowing dry nitrogen.

[Example 6]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-6) a metal chelate compound: "ORGATIXX" (registered trademark) TC-750 (manufactured by Matsumoto Fine Chemical Co., Ltd., di-iso-propoxide titanium bisethylacetoacetate): 16.19 parts by mass.

[Example 7]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-7) metal chelate compound: "ORGATIXX" (registered trademark) ZC-162 (manufactured by Matsumoto Fine Chemical Co., Ltd., zirconium tetraacetylacetonate): 18.61 parts by mass.

[Example 8]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (l-8) a metal chelate compound: "Orgatix" (registered trademark) ZC-580 (manufactured by Matsumoto Fine Chemical Co., Ltd., a di-n-butoxide zirconium bisethylacetoacetate/n-butanol = 70/30 mass % solution) was replaced with 18.91 parts by mass of a compound obtained by removing the solvent by blowing dry nitrogen.

[Example 9]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 94.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 4.49 parts by mass.

[Example 10]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 93.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 5.99 parts by mass.

[Example 11]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 91.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 8.98 parts by mass.

[Example 12]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 82.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150, which is component (l-5), added was changed to 22.45 parts by mass.

[Example 13]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 77.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 29.94 parts by mass.

[Example 14]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 74.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150, which is component (l-5), added was changed to 34.43 parts by mass.

[Example 15]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 72.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 37.42 parts by mass.

[Example 16]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 14, except that the average thickness of the metal chelate-containing silicone layer was changed to 10 μm.

[Example 17]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 14, except that the average thickness of the metal chelate-containing silicone layer was changed to 5 μm.

[Example 18]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 14, except that the average thickness of the metal chelate-containing silicone layer was changed to 2.5 μm.

[Example 19]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 17, except that the following metal chelate-free silicone layer-forming composition-1 was applied onto the metal chelate-containing silicone layer of the waterless lithographic printing plate precursor described in Example 17 using a slit die coater and heated at 100°C for 1 minute to provide a metal chelate-free silicone layer (second layer) with an average thickness of 0.125 µm.

<Metal Chelate-Free Silicone Layer-Forming Composition-1>
The following components (f-2) and (h-2) were added to a container and stirred and mixed until component (h-2) was dissolved. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove water from the solution. Just before application, component (k-2) was added and stirred and mixed for 30 minutes to obtain metal chelate-free silicone layer-forming composition-1.
(f-2) Isoparaffin solvent: "ISOPAR" (registered trademark) C (manufactured by ExxonMobil Chemical Company): 900.00 parts by mass (h-2) Siloxane compound having two or more silanol groups in the molecule (polydimethylsiloxane having silanol at both ends): DMS-S45 (manufactured by GELEST Inc., weight average molecular weight: 110,000, number of silanol groups in the molecule: 2.0): 96.00 parts by mass (k-2) Crosslinking agent: vinyltris(methylethylketoximino)silane: 4.00 parts by mass.

[Example 20]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 19, except that the average thickness of the metal chelate-free silicone layer was changed to 0.25 μm.

[Example 21]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 19, except that the average thickness of the metal chelate-free silicone layer was changed to 0.5 μm.

[Example 22]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 19, except that the average thickness of the metal chelate-free silicone layer was changed to 1 μm.

[Example 23]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 19, except that the average thickness of the metal chelate-free silicone layer was changed to 2 μm.

[Example 24]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the metal chelate-containing silicone layer-forming composition was changed to (l-1) AL-A(W): 28.46 parts by mass.

[Example 25]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the metal chelate-containing silicone layer-forming composition was changed to (l-2) ALCH-TR: 36.37 parts by mass.

[Example 26]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the metal chelate-containing silicone layer-forming composition was changed to (l-3) ALCH: 24.07 parts by mass.

[Example 27]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the composition for forming a metal chelate-containing silicone layer was changed to (l-4) “Orgatix” (registered trademark) TC-401, but was replaced with 38.99 parts by mass of a compound obtained by removing the solvent by blowing dry nitrogen.

[Example 28]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the metal chelate-containing silicone layer-forming composition was changed to (l-6) "Orgatix" (registered trademark) TC-750: 37.24 parts by mass.

[Example 29]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the metal chelate-containing silicone layer-forming composition was changed to (l-7) “Orgatix” (registered trademark) ZC-162: 42.80 parts by mass.

[Example 30]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the component (l-5) in the composition for forming a metal chelate-containing silicone layer was changed to (l-8) a compound obtained by removing the solvent by blowing dry nitrogen onto “Orgatix” (registered trademark) ZC-580: 43.50 parts by mass.

[Example 31]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the laser exposure amount was changed to 3 J/cm ² .

[Example 32]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the laser exposure was changed to 4 J/cm ² .

[Example 33]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the laser exposure was changed to 6 J/cm ² .

[Example 34]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the laser exposure amount was changed to 7 J/cm ² .

[Example 35]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the laser exposure amount was changed to 8 J/cm ² .

[Example 36]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that the metal chelate-containing silicone layer-forming composition was changed to the metal chelate-containing silicone layer-forming composition-2 described below.

<Metal chelate-containing silicone layer-forming composition-2>
The following components (f-1), (g-1) and (h-3) were added to a container and stirred and mixed until component (h-3) was dissolved. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove water from the solution. Just before application, component (k-2) was added and stirred and mixed for 30 minutes, after which component (l-5) was immediately added and stirred and mixed for 10 minutes, yielding a metal chelate-containing silicone layer-forming composition-2.
(f-1) "EXSOL" (registered trademark) DSP100/140: 240.00 parts by mass (g-1) Toluene: 60.00 parts by mass (h-3) Siloxane compound having two or more silanol groups in the molecule (polydimethylsiloxane having silanol at both ends): DMS-S42 (manufactured by GELEST Inc., weight average molecular weight: 77,000, number of silanol groups in the molecule: 2.0): 75.99 parts by mass (k-2) Crosslinking agent: vinyltris(methylethylketoximino)silane: 4.00 parts by mass (l-5) Compound obtained by removing the solvent from "ORGATIXX" (registered trademark) TC-150 by blowing dry nitrogen: 34.43 parts by mass.

[Example 37]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 21, except that a pattern was written from the metal chelate-free silicone layer side of the waterless lithographic printing plate precursor in air at an exposure dose of 2 J/ ^cm2 using a solid-state pulse laser having a wavelength of 266 nm: "AONano" (registered trademark) 266-3-20-V (manufactured by Advanced Optwave Corporation).

[Example 38]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 37, except that the laser exposure amount was changed to 3 J/cm ² .

[Example 39]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 37, except that the laser exposure was changed to 4 J/cm ² .

[Example 40]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 37, except that the laser exposure amount was changed to 5 J/cm ² .

[Example 41]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 37, except that the laser exposure was changed to 6 J/cm ² .

[Example 42]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 37, except that the laser exposure amount was changed to 7 J/cm ² .

[Example 43]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 36, except that a solid pulse laser having a wavelength of 266 nm was used to draw a pattern from the metal chelate-free silicone layer side of the waterless lithographic printing plate precursor in air at an exposure dose of 4 J/ ^cm2 .

[Example 44]
The primer layer-forming composition was applied to the outer peripheral surface of an aluminum alloy plate cylinder sleeve using a cylindrical slit die coater (manufactured by Toray Engineering Co., Ltd.), and heated at 180°C for 10 minutes to provide a seamless, continuous primer layer with an average thickness of 10 μm.

Next, the metal chelate-containing silicone layer-forming composition used in Example 14 was applied to the outer peripheral surface of the primer layer using a cylindrical slit die coater and heated at 100°C for 5 minutes to provide a seamless, continuous metal chelate-containing silicone layer with an average thickness of 5 μm.

Next, the metal chelate-free silicone layer-forming composition-1 was applied to the outer peripheral surface of the metal chelate-containing silicone layer using a cylindrical slit die coater and heated at 100°C for 5 minutes to provide a seamless, continuous metal chelate-free silicone layer with an average thickness of 0.5 μm, thereby obtaining a seamless waterless lithographic printing plate precursor.

A pattern was written on the metal chelate-free silicone layer side of the waterless lithographic printing plate precursor in air with an exposure dose of 5 J/cm ² using a solid pulse laser having a wavelength of 355 nm, to obtain a seamless waterless lithographic printing plate.

[Example 45]
A seamless waterless lithographic printing plate precursor and a seamless waterless lithographic printing plate were obtained in the same manner as in Example 44, except that a solid pulse laser having a wavelength of 266 nm was used to draw a pattern from the metal chelate-free silicone layer side of the seamless waterless lithographic printing plate precursor in air at an exposure dose of 4 J/ ^cm2 .

[Comparative Example 1]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the amount of DMS-V42 added, which was the component (h-1) of the metal chelate-containing silicone layer-forming composition-1, was changed to 97.47 parts by mass, and the metal chelate compound, component (l-1), was not added.

[Comparative Example 2]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the metal chelate-containing silicone layer-forming composition-1 was changed to the metal chelate-free silicone layer-forming composition-2 described below.

<Metal Chelate-Free Silicone Layer-Forming Composition-2>
The following components (f-1), (g-1) and (h-3) were added to a container and stirred and mixed until component (h-3) was dissolved. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove water from the solution. Just before application, component (k-2) was added and stirred and mixed for 30 minutes, after which component (l-5) was immediately added and stirred and mixed for 10 minutes, yielding a metal chelate-containing silicone layer-forming composition-2.
(f-1) "EXSOL" (registered trademark) DSP100/140: 240.00 parts by mass (g-1) Toluene: 60.00 parts by mass (h-3) DMS-S42: 98.66 parts by mass (k-2) Vinyltris(methylethylketoximino)silane: 4.00 parts by mass (l-5) Compound obtained by removing the solvent from "ORGATIXX" (registered trademark) TC-150 by blowing dry nitrogen: 0.50 parts by mass.

[Comparative Example 3]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 96.13 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 2.00 parts by mass.

[Comparative Example 4]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 5, except that the amount of DMS-V42, which is component (h-1) of the metal chelate-containing silicone layer-forming composition, added was changed to 67.47 parts by mass, and the amount of the compound obtained by removing the solvent from "Orgatix" (registered trademark) TC-150 by blowing dry nitrogen, which is component (l-5), added was changed to 44.91 parts by mass.

[Comparative Example 5]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the metal chelate component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (m-1) metal alkoxide: "Orgatix" (registered trademark) AL-3001 (manufactured by Matsumoto Fine Chemical Co., Ltd., aluminum tri-sec-butoxide): 9.40 parts by mass.

[Comparative Example 6]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the metal chelate component (l-1) of the metal chelate-containing silicone layer-forming composition-1 was changed to (m-2) metal alkoxide: "ORGATIXX" (registered trademark) TA-21 (manufactured by Matsumoto Fine Chemical Co., Ltd., titanium tri-n-butoxide): 12.99 parts by mass.

[Comparative Example 7]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that (l-1), which was the metal chelate component of the metal chelate-containing silicone layer-forming composition-1, was changed to (m-3) a metal alkoxide: "Orgatix" (registered trademark) ZA-65 (manufactured by Matsumoto Fine Chemical Co., Ltd., a solution of zirconium tetra-n-butoxide/n-butanol = 87/13 mass %), but was replaced with 14.64 parts by mass of a compound obtained by removing the solvent by blowing dry nitrogen.

[Comparative Example 8]
The following metal chelate-free silicone layer-forming composition-3 was prepared.

<Metal Chelate-Free Silicone Layer-Forming Composition-3>
The following components (f-3), (h-4), (i-2), (k-3) and (n-1) were placed in a container and mixed with stirring until the components were uniform. The resulting mixture was passed twice through a high-pressure valve homogenizer: Econizer Labo 02 (manufactured by Sanmaru Machinery Industry Co., Ltd.) to obtain metal chelate-free silicone layer-forming composition-3.
(f-3) 2-butanone: 900.00 parts by mass (h-4) Both ends silanol-polydimethylsiloxane: YF3802 (manufactured by Momentive Performance Materials Japan, LLC, weight average molecular weight: 125,000, number of silanol groups in molecule: 2.0): 60.00 parts by mass (i-2) Dibutyltin diacetate: 0.10 parts by mass (k-3) Methyltriacetoxysilane: 4.00 parts by mass (n-1) Photocatalyst particles: AMT-600 (anatase type photocatalyst titanium oxide particles, X-ray particle size: 30 nm, manufactured by Teika Co., Ltd.): 30.00 parts by mass.

Even in the case of a silicone layer-forming composition that did not contain a metal chelate immediately after dispersion, the photocatalyst particles quickly aggregated/settled, making it impossible to form a coating film.

[Comparative Example 9]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Example 1, except that the metal chelate-containing silicone layer-forming composition-1 was changed to the metal chelate-free silicone layer-forming composition-4 described below, the heating conditions after application were changed to 120° C. for 2 minutes, and the average thickness of the metal chelate-free silicone layer after heating was changed to 1 μm.

<Metal chelate-free ink-repellent silicone layer-forming composition-4>
The following components (f-4), (g-2), (h-5), (i-3), (k-4) and (n-2) were placed in a container and mixed with stirring until the components were uniformly mixed, thereby obtaining metal chelate-free ink-repellent silicone layer-forming composition-4.
(f-4) 1,4-dioxane: 5.00 parts by mass (g-2) 2-propanol: 5.00 parts by mass (h-5) Both-end carbinol-modified polydimethylsiloxane: X-22-160AS (Shin-Etsu Chemical Co., Ltd., weight average molecular weight: 1,000, number of carbinol groups in the molecule: 2.0): 9.00 parts by mass (i-3) Reaction catalyst: dibutyltin dilaurate: 0.05 parts by mass (k-4) Crosslinking agent: Coronate L (Tosoh Corporation, trimethylolpropane / tolylene diisocyanate trimer adduct, solid content concentration: 75% by mass (solvent: ethyl acetate)): 1.00 parts by mass (n-2) Photocatalyst particles: ST-01 (Ishihara Sangyo Kaisha, Ltd., anatase-type photocatalyst titanium oxide particles, X-ray particle size: 7 nm): 1.00 parts by mass.

[Comparative Example 10]
The following metal chelate-free silicone layer-forming composition-5 was applied onto the metal chelate-free silicone layer of Comparative Example 1 and heated at 100° C. for 80 seconds to provide a metal chelate-free silicone layer (second layer) with an average thickness of 0.4 μm, thereby obtaining a waterless lithographic printing plate precursor.

<Metal chelate-free silicone layer-forming composition-5>
The following components (f-2), (h-6), (i-1) and (j-1) were added to a container and stirred and mixed until the components were uniform. The resulting solution was bubbled with dry nitrogen for 20 minutes to remove water from the solution. Just before coating, component (k-1) was added and stirred to obtain metal chelate-free silicone layer-forming composition-5.
(f-2) Isoparaffin solvent: "Isopar" (registered trademark) C (manufactured by ExxonMobil Chemical Company): 895.0 parts by mass (h-6) Siloxane compound having three or more vinyl groups in the molecule (both terminal trimethylsiloxy-vinylmethylsiloxane-dimethylsiloxane copolymer): VDT-954 (manufactured by GELEST Inc., weight average molecular weight: 225,000, vinyl group concentration: 4.29% by mass, number of vinyl groups in the molecule: 357.2): 70.0 parts by mass (i-1) XC94-C4326: 3.5 parts by mass (j-1) 2-methyl-3-butyn-2-ol: 1.5 parts by mass (k-1) HMS-993: 30.0 parts by mass.

The second layer side of the obtained waterless lithographic printing plate precursor was exposed to laser light in air using an ArF excimer pulse laser with a wavelength of 193 nm: Excimer Laser MLI Series (manufactured by Mlase Corporation) under conditions of exposure dose: 75 mJ/ ^cm2 and pulse repetition frequency: 10 Hz, and the second layer and the upper part of the first layer in the laser-exposed area were ablated to obtain a waterless lithographic printing plate.

[Comparative Example 11]
A waterless lithographic printing plate precursor and a waterless lithographic printing plate were obtained in the same manner as in Comparative Example 10, except that the laser exposure amount was changed to 150 mJ/cm ² .

The element concentrations in each layer for Examples 1 to 45 and Comparative Examples 1 to 11 are shown in Tables 1 to 3. The evaluation results are shown in Tables 4 to 6.

Claims (17)

A waterless lithographic printing plate precursor having a metal chelate-containing silicone layer on a support, in which the metal concentration derived from the metal chelate in the metal chelate-containing silicone layer is 0.2 to 1.8 atom % as measured by X-ray photoelectric spectroscopy. The waterless lithographic printing plate precursor according to claim 1, wherein the metal chelate contains a chelate ring formed from a β-diketone compound and/or a β-ketoester compound and a metal. The waterless lithographic printing plate precursor according to claim 2, which contains acetylacetone as the β-diketone compound. The waterless lithographic printing plate precursor according to claim 2, wherein the β-ketoester compound contains an alkyl acetoacetate ester, and the alkyl has 2 to 8 carbon atoms. The waterless lithographic printing plate precursor according to any one of claims 1 to 4, wherein the metal comprises aluminum, titanium and/or zirconium. The waterless lithographic printing plate precursor according to any one of claims 1 to 5, wherein the silicon concentration in the metal chelate-containing silicone layer is 15.5 to 24.5 atom %, the oxygen concentration is 25.0 to 28.5 atom %, and the carbon concentration is 50.0 to 57.0 atom %, as measured by X-ray photoelectric spectroscopy. The waterless lithographic printing plate precursor according to any one of claims 1 to 6, wherein the average thickness of the metal chelate-containing silicone layer is 5 μm or more. The waterless lithographic printing plate precursor according to any one of claims 1 to 7, further comprising a metal chelate-free silicone layer on the metal chelate-containing silicone layer. The waterless lithographic printing plate precursor according to claim 8, wherein the silicon concentration in the metal chelate-free silicone layer is 22 to 26 atom %, the oxygen concentration is 24 to 28 atom %, and the carbon concentration is 48 to 52 atom %, as measured by X-ray photoelectron spectroscopy. The waterless lithographic printing plate precursor according to claim 8 or 9, wherein the metal chelate-free silicone layer has an average thickness of 0.1 μm or more. The waterless lithographic printing plate precursor according to any one of claims 1 to 10, wherein the support is cylindrical. A method for producing a waterless lithographic printing plate, comprising exposing the waterless lithographic printing plate precursor according to any one of claims 1 to 11 to active energy rays from the metal chelate-containing silicone layer side or the metal chelate-free silicone layer side to form an ink-receiving portion. The method for producing a waterless lithographic printing plate according to claim 12, wherein the peak wavelength of the active energy rays is 200 to 600 nm. The method for producing a waterless lithographic printing plate according to claim 12 or 13, wherein the active energy rays are a pulsed laser. The method for producing a waterless lithographic printing plate according to claim 14, wherein the exposure dose of the pulsed laser is 2 to 8 J/ ^cm2 . at least
(1) A step of continuously applying onto a support a composition for forming a metal chelate-containing silicone layer, the composition comprising a polysiloxane having two or more silanol groups or vinyl groups in the molecule, a crosslinker having three or more functional groups in the molecule that are reactive with the silanol groups or the vinyl groups, and a metal chelate compound having one or more chelate rings in the molecule, the content of the metal chelate compound being 4 to 60 mass % of the total solid content; and
(2) A step of curing the coating film obtained in step (1) to form a metal chelate-containing silicone layer.
The method for producing a waterless lithographic printing plate precursor according to any one of claims 1 to 11, comprising: Before or after the step (2),
(3) continuously applying a composition for forming a metal chelate-free silicone layer onto the coating film obtained in step (1) or the metal chelate-containing silicone layer obtained in step (2); and
(4) A step of curing the coating film obtained in the step (3) to form a metal chelate-free silicone layer.
The method for producing a waterless lithographic printing plate precursor according to claim 16 ,