JP2008073909A - Manufacturing method of printing plate and inkjet recording equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a printing plate which enables the manufacture of a lithographic printing plate of a processless type and attainment of the printing plate excellent in plate wear resistance with a resolution maintained, at low cost and with ease, and inkjet recording equipment used therefor. <P>SOLUTION: The manufacturing method of the printing plate has a process for forming an image by supplying a liquid droplet for image formation, in the shape of the image, onto the material of the printing plate. The process for forming the image by supplying the liquid droplet in the shape of the image is provided in a plurality. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a printing plate, and more particularly to a method for producing a processless type lithographic printing plate.

  2. Description of the Related Art In recent years, CTP (computer to plate) systems that record digital image data directly on a printing plate material with a laser light source have become widespread in the technology for producing printing plates for offset printing.

  As a printing plate material used in the CTP system, there is a need for a printing plate material that does not require development processing using a processing solution containing a special agent (for example, alkali, acid, solvent, etc.) and can be applied to a conventional printing press. For example, phase change type printing plate materials that do not require any development processing, printing plate materials that are treated with water or a substantially neutral processing liquid mainly composed of water, and initial printing on a printing press There are known printing plate materials called chemical-free type printing plate materials and processless type printing plate materials, such as printing plate materials that are developed in stages and do not particularly require a developing step.

  As these processless CTPs, an on-machine development type in which a non-image portion of an image forming layer is removed using dampening water or ink on a printing machine is known. Examples of this processless CTP include, for example, Japanese Patent No. 2938397 and As disclosed in Japanese Patent No. 2938398, there is known a printing plate material provided with a thermal image forming layer containing a thermoplastic fine particle, a water-soluble binder, and a photothermal conversion material on a hydrophilic layer or an aluminum grain. Yes. In these printing plate materials, an image is formed by irradiating an actinic ray such as a laser imagewise, and a non-image part is removed on a printing machine and used as a printing plate.

  On the other hand, as an image forming method using a processless type printing plate material, an inkjet recording method has been proposed as one of the effective means.

  Processless printing plates using an inkjet recording method generally apply a lipophilic image-forming material image-wise by an inkjet recording method to a printing plate material having a hydrophilic surface. The image forming material is an image portion.

  As a method for producing a printing plate using an ink jet recording method, a method for producing a printing plate by supplying hot melt ink onto a substrate to form an image (see Patent Document 1), and using oil-based ink using an electrostatic field. Plate making method for forming an image by inkjet method (see Patent Document 2), or plate making method for forming an image by supplying a photopolymerizable ink composition onto a substrate having an ink absorbing layer (Patent Document) 3) is known.

However, when using a printing plate material provided with the above thermal image forming layer, there is a problem that a relatively expensive exposure apparatus is required for exposure, and the printing durability may be insufficient. The plate making method using the ink jet recording method has problems that the resolution may not be sufficient and the printing durability may be insufficient.
JP-A-9-58144 Japanese Patent Laid-Open No. 10-272753 JP-A-5-204138

  An object of the present invention is to prepare a printing plate capable of producing a processless type lithographic printing plate, easily obtaining a printing plate having excellent printing durability while maintaining resolution at a low cost, and An object of the present invention is to provide an ink jet recording apparatus used therefor.

The above object of the present invention is achieved by the following configurations.
1. In a printing plate manufacturing method including a step of supplying an image-forming droplet on a printing plate material to form an image, the step of supplying the image-forming droplet in an image manner to form an image A method for preparing a printing plate, comprising a plurality of printing plates.
2. 2. The method for producing a printing plate according to 1, wherein the image forming droplet is an actinic ray curable ink droplet.
3. 3. The method for producing a printing plate according to 1 or 2, wherein the printing plate material is a base material having a hydrophilic surface.
4). 3. The method for preparing a printing plate according to 1 or 2, wherein the printing plate material is a printing plate material having an ink receiving layer on a substrate having a hydrophilic surface.
5. 2. The printing plate preparation method according to 1, wherein the printing plate material is a printing plate material having an image forming layer containing a lipophilic component on a substrate having a hydrophilic surface.
6). 6. The method for preparing a printing plate according to 5, wherein the image forming droplets are actinic ray curable ink droplets or a liquid droplet containing an adhesive component.
7). The method for producing a printing plate according to any one of 1 to 6, wherein the image forming droplet is a droplet by an ink jet recording method.
8). 2. The printing plate according to 1, wherein after the step of supplying the image forming droplets imagewise to form an image, the printing plate material having the image is developed on a printing machine to produce a printing plate. Manufacturing method.
An ink jet recording apparatus, which is used in the method for producing a printing plate according to 9.7.

  According to the above configuration of the present invention, a processless type lithographic printing plate can be produced, and a printing plate production method capable of obtaining a printing plate excellent in printing durability while maintaining resolution at a low cost is easily obtained. In addition, an ink jet recording apparatus used therefor can be provided.

  The present invention relates to a method for producing a printing plate comprising a step of supplying an image-forming droplet on a printing plate material to form an image, and supplying the image-forming droplet imagewise to form an image. There are a plurality of forming steps.

  In the present invention, in particular, a processless type lithographic printing plate can be produced by supplying image-forming droplets multiple times for the same image in an image-like manner. A printing plate having excellent printing durability while maintaining resolution can be obtained.

  That is, in a printing plate manufacturing method including a step of supplying an image-forming droplet on a printing plate material to form an image, the image-forming droplet is supplied image-wise to form an image. The step includes a plurality of steps of forming an image on the same image.

  In the method for preparing a printing plate of the present invention, there are a plurality of steps of supplying an image-forming droplet to the printing plate material in an image-like manner to form an image. After supplying the liquid droplets image-wise, the liquid droplets are supplied at least once image-wise based on the same image to the portion of the printing plate material where the image-forming liquid droplets are supplied image-wise.

  In the present invention, as a method for supplying droplets in an image-like manner, an ink jet recording method is preferably used.

  In the present invention, one of the preferred embodiments is the case where the image forming droplet according to the present invention is a droplet of actinic ray curable ink.

  When supplying actinic ray curable ink droplets on the printing plate material in an image-like manner, the actinic ray curable ink droplets are once supplied in an image-like manner and then irradiated with actinic rays for curing. The droplet supplied on the material is cured, and further, on the basis of the same image, an actinic ray curable ink droplet is supplied on the cured portion and irradiated with actinic rays for curing. .

  When the viscosity of the active curable ink is high, the second supply may be performed before curing, but more preferably after being cured once.

  The number of times of supplying the droplets is preferably 2 to 4 times, particularly preferably 2 or 3 times.

  In addition, as a method of supplying droplets after supplying the first droplet, the first supply may be performed once for all the images, followed by a curing process and then a batch process. However, a continuous process in which the curing process is performed and the droplets are supplied for the second and subsequent times may be used.

  The continuous processing can be performed by an ink jet recording apparatus having a plurality of sets of ink heads each having a nozzle for supplying ink, and further having actinic ray irradiation means between the plurality of ink heads.

(Actinic ray curable ink)
The actinic ray curable ink according to the present invention contains at least an actinic ray polymerizable compound (hereinafter also simply referred to as a polymerizable compound). A coloring material can also be added for the purpose of obtaining visible image quality.

  Examples of the polymerizable compound include a radical polymerizable compound and a cationic polymerizable compound.

  The radical polymerizable compound is a compound having an ethylenically unsaturated bond capable of radical polymerization, and may be any compound as long as it has at least one ethylenically unsaturated bond capable of radical polymerization in the molecule. , Oligomers, polymers and the like having a chemical form. Only one kind of radically polymerizable compound may be used, or two or more kinds thereof may be used in combination at an arbitrary ratio in order to improve desired properties. A polyfunctional compound having two or more functional groups is more preferable than a monofunctional compound. More preferably, two or more polyfunctional compounds are used in combination for controlling performance such as reactivity and physical properties.

  Examples of compounds having an ethylenically unsaturated bond capable of radical polymerization include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid and their salts, esters, urethanes, amides. And radically polymerizable compounds such as unsaturated monomers, acrylonitrile, styrene, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes. Specifically, acryloylmorpholine, phenoxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate Bis (4-acryloxypolyethoxyphenyl) propane, EO-modified bisphenol A diacrylate, polyethylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, glycerin epoxy acrylate, neopentyl glycol diacrylate, 1,6-hexane Diol diacrylate, ethylene glycol dia Relate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, trimethylolpropane triacrylate, Acrylic acid derivatives such as tetramethylol methane tetraacrylate, oligoester acrylate, N-methylol acrylamide, diacetone acrylamide, epoxy acrylate, methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, allyl methacrylate, glycine Methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane Examples include methacrylic derivatives such as trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, and other derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, and triallyl trimellitate. , Yamashita Shinzo, “Crosslinking agent handbook” (Taisei, 1981); Kato Kiyomi, “UV / EB Curing Han” Dobook (raw material edition) "(1985, Polymer publication society); Radtech study edition," Application and market of UV / EB curing technology ", p. 79, (1989, CMC); Eiichiro Takiyama," Polyester Commercially available products described in “Resin Handbook”, (1988, Nikkan Kogyo Shimbun), or radically polymerizable or crosslinkable monomers, oligomers and polymers known in the industry can be used. The amount of the radical polymerizable compound added is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

  Examples of the cationic polymerizable compound include an epoxy compound, an oxetane compound, a vinyl ether compound and the like that are polymerized by cationic polymerization.

  Examples of the epoxy compound that can be used in the present invention are described in JP-A No. 2001-220526, JP-A No. 2002-188025, JP-A No. 2002-317139, JP-A No. 2003-55449, JP-A No. 2003-73481, and the like. Any known epoxy compound can be used by epoxidizing a compound having at least one cycloalkane ring such as cyclohexene or cyclopentene ring with a suitable oxidizing agent such as hydrogen peroxide or peracid. The resulting cyclohexene oxide or cyclopentene oxide-containing compound is preferred.

  As the oxetane compound that can be used in the present invention, any known oxetane compound as introduced in JP-A Nos. 2001-220526 and 2001-310937 can be used.

  Examples of the vinyl ether compound that can be used in the present invention include ethylene glycol divinyl ether, ethylene glycol monovinyl ether, diethylene glycol divinyl ether, triethylene glycol monovinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, and dipropylene glycol divinyl ether. , Butanediol divinyl ether, hexanediol divinyl ether, cyclohexane dimethanol divinyl ether, hydroxyethyl monovinyl ether, hydroxynonyl monovinyl ether, trimethylolpropane trivinyl ether and other di- or trivinyl ether compounds, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether Monomers such as octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl ether-o-propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether, octadecyl vinyl ether Examples include vinyl ether compounds.

  One of the polymerizable compounds may be used alone, but two or more may be used in appropriate combination.

  As the coloring material, a coloring material that can be dissolved or dispersed in the main component of the polymerizable compound, that is, various dyes and pigments can be used. When a pigment is added, the dispersibility has a great influence on the coloring degree. In order to give For the dispersion of the pigment, a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, a paint shaker, or the like can be used. It is also possible to add a dispersant when dispersing the pigment. As the dispersant, it is preferable to use a polymer dispersant. Examples of the polymer dispersant include Solsperse series manufactured by Zeneca. Moreover, it is also possible to use a synergist according to various pigments as a dispersion aid. These dispersants and dispersion aids are preferably added in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of the pigment. Although the dispersion medium is a solvent or a polymerizable compound, the radiation curable ink used in the present invention is preferably solventless because it reacts and cures immediately after ink landing. If the solvent remains in the cured image, the solvent resistance deteriorates and the VOC of the remaining solvent arises.

  For the dispersion, it is preferable that the average particle diameter is 0.08 to 0.5 μm, and the pigment, the dispersant, and the dispersion medium are selected so that the maximum particle diameter is 0.3 to 10 μm, preferably 0.3 to 3 μm. Set dispersion conditions and filtration conditions. By controlling the particle size, clogging of the head nozzle can be suppressed, and ink storage stability, ink transparency, and curing sensitivity can be maintained. The colorant is preferably added in an amount of 0.1% to 10% by weight of the total ink.

  The actinic ray curable ink according to the present invention preferably has a surface tension of 25 to 35 mN / m from the viewpoint of ink discharge properties, dot size, dot shape quality, and the like.

  In addition, the contact angle of the actinic ray curable ink is preferably 3 to 10 degrees, particularly 4 to 8 degrees, from the viewpoints of ejectability and dot shape quality.

  In the lithographic printing plate of the present invention, the active energy ray-curable inkjet ink preferably contains 20 to 50% by mass of a polymerizable compound having a surface tension of 40 to 50 mN / m.

  The surface tension is preferably 40 to 50 mN / m, and more preferably 40 to 47 mN / m. If it is less than 40 mN / m, the ejectability from the ink jet head becomes poor, the dot size becomes too small, the dot shape is also bad, and there is a concern that the print quality will deteriorate. On the other hand, if it exceeds 50 mN / m, the ejection performance from the ink jet head becomes unsatisfactory, the dot size becomes too large, the dot shape is poor, and there is a concern that the print quality will deteriorate.

  And the quantity to contain is preferable 20-50 mass%, and it is more preferable that it is 20-40 mass%. If it is less than 20% by mass, the ejectability from the ink jet head becomes poor, the dot size becomes too small, the dot shape is also bad, and there is a concern that the print quality will deteriorate. On the other hand, if it exceeds 50% by mass, the ejectability from the ink jet head becomes poor, the dot size becomes too large, the dot shape is also bad, and there is a concern that the print quality will deteriorate.

  In order to adjust the surface tension, among the polymerizable compounds, for example, acryloylmorpholine, phenoxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, EO-modified bisphenol A diacrylate, polyethylene glycol diacrylate, pentaerythritol triacrylate By using an acrylate compound such as pentaerythritol tetraacrylate and glycerin epoxy acrylate, an epoxy compound such as 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, and the like, it can be easily adjusted.

  Examples of actinic rays for curing the ink include electron beams, X-rays, UV light, visible light, and infrared light. When using an electron beam or X-ray, a normal polymerization initiator is not required for the ink. However, when UV light, visible light, or infrared light is used as the active light, radicals corresponding to the respective wavelengths are used. A polymerization initiator, a cationic polymerization initiator, an initiation assistant, and a sensitizing dye are added.

  These amounts require 1-10 parts by weight of the total ink. Various known compounds can be used as the initiator, but the initiator is selected from those that dissolve in the polymerizable compound. Specific examples of the initiator include radical polymerization initiators such as xanthone or thioxanthone, benzophenone, quinone, and phosphine oxide, and cationic polymerization initiators such as sulfonium salt, iodonium salt, and diazonium salt.

  Moreover, in order to improve preservability, 200-20000 ppm of polymerization inhibitors can be added.

  In addition to this, surfactants, leveling additives, matting agents, polyester resins, polyurethane resins, vinyl resins, acrylic resins, rubber resins, and waxes are added to adjust film properties as necessary. can do.

  From the viewpoint of adhesion to the printing plate material, it is also effective to add a trace amount of organic solvent. In this case, it is effective to add in a range that does not cause the problem of solvent resistance and VOC, and the amount is 0.1 to 5%, preferably 0.1 to 3%.

  In addition, as a means for preventing a decrease in sensitivity due to the light-shielding effect due to the ink color material, it is possible to combine a cationically polymerizable monomer having a long initiator lifetime with an initiator to obtain a radical-cation hybrid curable ink.

  The actinic ray curable ink of the present invention preferably contains a surfactant from the viewpoints of ejectability and dot shape quality. As the surfactant, a surfactant having an HLB of 11 or less is preferable. For example, a polyether-modified silicone oil having an HLB of 5.0 to 7.5 is preferably used. The addition amount of the surfactant is 0.001 to 5% by mass, preferably 0.01 to 0.2% by mass.

  The viscosity of the actinic ray curable ink according to the present invention is preferably 5 to 100 mPa · s, particularly preferably 8 to 40 mPa · s at 25 ° C.

  The temperature of the ink jet head when ejecting droplets by the ink jet recording method is preferably 10 ° C to 40 ° C, and more preferably 20 ° C to 30 ° C.

  Curing of the actinic ray curable ink by irradiation with actinic rays can be performed by a conventional method. Examples of active energy rays include lasers, light emitting diodes, xenon flash lamps, halogen lamps, carbon arc lamps, metal halide lamps, tungsten lamps, high pressure mercury lamps, and electrodeless light sources.

[Printing plate materials]
The printing plate material according to the present invention includes a substrate having a hydrophilic surface, a printing plate material having an ink receiving layer on a substrate having a hydrophilic surface, or an oleophilic component on a substrate having a hydrophilic surface. A printing plate material having an image forming layer is used.

  The hydrophilic surface according to the present invention is a surface that can be a non-image part having water retention and printing ink repellency during printing, and the substrate having the hydrophilic surface according to the present invention is a substrate. It can be obtained by a method of hydrophilizing the surface of the substrate or a method of providing a hydrophilic layer containing a hydrophilic substance on a substrate.

  The printing plate material according to the present invention may have a backing layer or the like, if necessary, on the surface opposite to the side having a hydrophilic surface.

[Base material]
As a base material which concerns on this invention, the well-known base material used for the conventional printing plate material can be used.

  Examples of the substrate include a metal plate, a plastic film, paper treated with polyolefin, a composite substrate obtained by appropriately bonding the above materials, and the like.

  The thickness of the base material is not particularly limited as long as it can be attached to a printing press, but a thickness of 50 to 500 μm is generally easy to handle.

  Examples of the plastic film include films of polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, polycarbonate, polysulfone, polyphenylene oxide, cellulose esters, and the like.

  In the present invention, among these plastic films, polyester films such as polyethylene terephthalate (hereinafter sometimes abbreviated as PET) and polyethylene naphthalate (hereinafter sometimes abbreviated as PEN) are preferably used as the base material. The

  Furthermore, it is preferable to use a base material having a thermal dimensional change rate of 0.001% to 0.04% at 120 ° C. for 30 seconds obtained by the method described in JP-A-10-10676.

  A preferable polyester film is an unstretched polyester film, a uniaxially stretched polyester film, or a biaxially stretched polyester film.

  Of these, a longitudinally stretched polyester film uniaxially stretched in the film extrusion direction (longitudinal direction) is particularly preferred.

  PET is polymerized with terephthalic acid and ethylene glycol, and PEN polymerized with naphthalenedicarboxylic acid and ethylene glycol as constituent components.

  The dicarboxylic acid or diol constituting PET or PEN may be polymerized by mixing other appropriate one type or two or more third components. A suitable third component is a compound having a divalent ester-forming functional group. Examples of the dicarboxylic acid include the following.

  Terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenylether dicarboxylic acid, diphenylethanedicarboxylic acid, cyclohexanedicarboxylic acid, diphenyldicarboxylic acid, diphenylthioether dicarboxylic acid Examples thereof include acid, diphenyl ketone dicarboxylic acid, and phenylindane dicarboxylic acid.

  Examples of glycols include propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, and bis (4- Hydroxyphenyl) sulfone, bisphenol full orange hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone, cyclohexanediol and the like.

  As the third component, a polyfunctional carboxylic acid or a polyhydric alcohol can also be mixed, but these can be mixed in an amount of about 0.001 to 5% by mass with respect to all the polyester components.

  The intrinsic viscosity of the polyester film is preferably 0.5 to 0.8. Moreover, you may mix and use what has a different intrinsic viscosity.

  The polymerization method of the polyester film is not particularly limited, and can be produced according to a conventionally known polyester polymerization method.

  For example, a direct ester is obtained by directly esterifying a dicarboxylic acid component with a diol component, diesterifying one hydroxyl group of the diol to a dicarboxylic acid, and heating the other diol under reduced pressure to distill off the excess diol. A dialkyl ester (for example, dimethyl ester) as a dicarboxylic acid component, and a transesterification reaction between this and a diol component to distill alkyl alcohol (for example, methanol) to distill one hydroxyl group of the diol to a dicarboxylic acid. It is possible to use a transesterification method in which polymerization is performed by esterification into an acid and further heating and distilling off excess diol components under reduced pressure.

As the catalyst, a transesterification catalyst, a polymerization reaction catalyst, and a heat stabilizer used for synthesis of a normal polyester can be used. Examples of transesterification catalysts include Ca (OAc) ₂ .H ₂ O, Zn (OAc) ₂ .2H ₂ O, Mn (OAc) ₂ .4H ₂ O, Mg (OAc) ₂ .4H ₂ O, and the like. Examples of the polymerization reaction catalyst include Sb ₂ O ₃ and GeO ₂ . Examples of the heat stabilizer include phosphoric acid, phosphorous acid, PO (OH) (CH ₃ ) ₃ , PO (OC ₆ H ₅ ) ₃ , P (OC ₆ H ₅ ) _{3 and the} like. In addition, anti-coloring agent, crystal nucleating agent, slip agent, stabilizer, anti-blocking agent, UV absorber, viscosity modifier, clearing agent, antistatic agent, pH adjuster, dye, pigment, etc. May be added.

  In order to stabilize the dimensions during printing and prevent color misregistration during color printing, it is preferable to heat-treat the polyester film after stretching and heat setting.

  The heat treatment is preferably accomplished by the following means after cooling and winding after completion of heat setting and then unwinding in a separate step.

  As a heat treatment method, a transport method in which both ends of a film such as a tenter are gripped with pins or clips, a roll transport method using a plurality of roll groups, a method of transporting air by blowing air on the film, etc. A method in which heated air is blown from one side or both sides of a film surface through a slit), a method using radiant heat by an infrared heater, a method in which a plurality of heated rolls are brought into contact with each other, a method in which heat treatment is performed alone or in combination, and a film is self-weighted. It is preferable to use one or a combination of a plurality of conveying methods such as winding in the lower part.

  The tension of the heat treatment can be adjusted by adjusting the torque of the take-up roll and / or the delivery roll, and / or by installing a dancer roll in the process and adjusting the load applied to the dancer roll.

  When changing the tension during the heat treatment and / or cooling after the heat treatment, a desired tension state may be set by installing dancer rolls before and after these processes and / or in the processes and adjusting their loads. . In addition, it is possible to effectively change the conveyance tension by vibration by reducing the span between the heat treatment rolls.

  In order to reduce the dimensional change during the subsequent heat treatment (heat development) without hindering the progress of the heat shrinkage, it is desirable to make the conveyance tension as low as possible and lengthen the heat treatment time.

  As the treatment temperature, a temperature range of Tg + 50 ° C. to Tg + 150 ° C. of the polyester film is preferable, and in that temperature range, the transport tension is preferably 5 Pa to 1 MPa, more preferably 5 Pa to 500 kPa, and further preferably 5 Pa to 200 kPa. The time is preferably 30 seconds to 30 minutes, more preferably 30 seconds to 15 minutes. By using the above temperature range, conveyance tension range and treatment time, the flatness of the substrate does not deteriorate due to a partial difference in the thermal shrinkage of the substrate during heat treatment, and fine scratches due to friction with the conveyance roll, etc. Etc. can also be suppressed.

  The heat treatment is preferably performed at least once in order to obtain a desired dimensional change rate, and can be performed twice or more as necessary.

  In order to prevent the deterioration of flatness due to cooling at this time, the heat-treated polyester film is cooled from a temperature near Tg to room temperature, and at least −5 ° C./second or more until it is lowered to room temperature across Tg. It is preferable to cool with.

  In the case of a polyester film base material, the water content of the base material is preferably 0.5% by mass or less in order to satisfactorily carry in an exposure apparatus or the like. The moisture content of the substrate is D ′ represented by the following formula.

D ′ (mass%) = (w ′ / W ′) × 100
In the formula, W ′ is the mass of the substrate in a humidity conditioning equilibrium under an atmosphere of 25 ° C. and 60% relative humidity, and w ′ is the moisture of the substrate in a humidity conditioning equilibrium under an atmosphere of 25 ° C. and 60% relative humidity. Represents content.

  The water content of the substrate is preferably 0.5% by mass or less, more preferably 0.01 to 0.5% by mass, and particularly preferably 0.01 to 0.3% by mass.

  As means for controlling the moisture content of the substrate to 0.5% by mass or less, (1) the substrate is heat-treated at 100 ° C. or more immediately before applying the coating solution for the hydrophilic layer and other layers, (2) Control the relative humidity in the step of applying the coating solution for the hydrophilic layer and other layers. (3) Before applying the coating solution for the hydrophilic layer and other layers, heat-treat the substrate at 100 ° C. or higher to prevent moisture. Cover and store with a sheet, and apply immediately after opening. Two or more of these may be combined.

(Fine particles)
It is preferable to add 0.01 to 10 μm of particles of 0.01 to 10 μm in the polyester base material in order to improve handling properties.

  These particles may be either organic or inorganic.

  Examples of inorganic substances include silica described in Swiss Patent No. 330,158 and the like, glass powder described in French Patent No. 1,296,995, and British Patent No. 1,173,181. Alkaline earth metals or carbonates such as cadmium and zinc described in the book can be used. Examples of organic substances include starch described in US Pat. No. 2,322,037 and the like, starch derivatives described in Belgian Patent 625,451 and British Patent 981,198, and the like. No. 44-3643, etc., polyvinyl alcohol described in Swiss Patent No. 330,158, etc., polymethacrylate described in US Pat. No. 3,079,257, etc., polyacrylonitrile described in US Pat. Organic fine particles such as polycarbonate described in Japanese Patent No. 3,022,169 can be used. The shape of the particles may be either regular or irregular.

(Applying undercoat layer to substrate)
In the polyester film base material, easy adhesion treatment or undercoat layer coating can be performed in order to have various functions.

  Examples of the easy adhesion treatment include corona discharge treatment, flame treatment, plasma treatment, and ultraviolet irradiation treatment.

  As the undercoat layer, a layer containing gelatin or latex is preferably provided on the polyester film substrate. Among them, the antistatic undercoat layer described in paragraph Nos. 0044 to 0116 of JP-A-7-191433 is preferably used. Further, a conductive layer such as a conductive polymer-containing layer described in paragraph Nos. 0031 to 0073 of JP-A-7-20596 or a metal oxide-containing layer described in paragraph Nos. 0074 to 0081 of JP-A-7-20596 is provided. It is preferable. The conductive layer may be coated on either side as long as it is on the polyester film substrate, but it is preferably coated on the opposite side of the image forming layer with respect to the substrate. When this conductive layer is provided, the chargeability is improved, the adhesion of dust and the like is reduced, and white spots failure during printing is greatly reduced.

(Hydrophilic layer)
In the present invention, when the above plastic film is used as a substrate, it is preferable to provide a hydrophilic layer on the substrate to provide a substrate having a hydrophilic surface.

  In this case, the hydrophilic layer preferably has a porous structure.

  In order to form a hydrophilic layer having a porous structure, the following materials for forming a hydrophilic matrix are preferably used.

  As a material for forming the hydrophilic matrix, a metal oxide is preferable.

(Metal oxide)
The metal oxide preferably contains fine metal oxide particles, and examples thereof include colloidal silica, alumina sol, titania sol, and other metal oxide sols. The form of the metal oxide fine particles may be spherical, needle-like, feather-like or any other form. The average particle diameter is preferably in the range of 3 to 100 nm, and several kinds of metal oxides having different average particle diameters are used. Fine particles can be used in combination. The surface of the particles may be surface treated.

  The metal oxide fine particles can be used as a binder by utilizing the film forming property. The decrease in hydrophilicity is less than when an organic binder is used, and it is suitable for use in a hydrophilic layer.

(Colloidal silica)
Among these, colloidal silica can be particularly preferably used. Colloidal silica has the advantage of high film-forming properties even under relatively low temperature drying conditions, and can provide good strength. The colloidal silica preferably includes necklace-like colloidal silica, which will be described later, and fine particle colloidal silica having an average particle size of 20 nm or less, and the colloidal silica preferably exhibits alkalinity as a colloidal solution.

  Necklace-shaped colloidal silica is a general term for an aqueous dispersion of spherical silica whose primary particle diameter is of the order of nm, and spherical colloidal silica having a primary particle diameter of 10 to 50 nm bonded to a length of 50 to 400 nm. It means colloidal silica in the form of “pearl necklace”.

  The pearl necklace shape (that is, a pearl necklace shape) means that the image of the state in which the silica particles of colloidal silica are connected and linked has a shape like a pearl necklace.

  The bond between the silica particles constituting the necklace-shaped colloidal silica is presumed to be —Si—O—Si— in which —SiOH groups present on the surface of the silica particles are dehydrated. Specific examples of the colloidal silica in the form of necklace include “Snowtex-PS” series manufactured by Nissan Chemical Industries, Ltd., and the product name is “Snowtex-PS-S” (the average particle diameter in the connected state is 110 ")," Snowtex-PS-M (average particle size in the connected state is about 120 nm) "and" Snowtex-PS-L (average particle size in the connected state is about 170 nm) " Acidic products corresponding to the above are "Snowtex-PS-SO", "Snowtex-PS-MO" and "Snowtex-PS-LO".

  By adding necklace-like colloidal silica, it becomes possible to maintain the strength while ensuring the porosity of the layer, and it can be preferably used as a porous material for the hydrophilic layer matrix. Among these, when “Snowtex PS-S”, “Snowtex PS-M”, and “Snowtex PS-L” are used, the strength of the hydrophilic layer is improved and the number of printed sheets is large. However, it is particularly preferable because the occurrence of soiling is suppressed.

  Further, it is known that colloidal silica has a stronger binding force as the particle size is smaller. In the present invention, it is preferable to use colloidal silica having an average particle size of 20 nm or less, and more preferably 3 to 15 nm. Is.

  As described above, among the colloidal silica, an alkaline one is particularly preferable because it has an effect of suppressing the occurrence of soiling. Examples of the alkaline colloidal silica having an average particle diameter in this range include, for example, “Snowtex-20 (particle diameter 10-20 nm)”, “Snowtex-30 (particle diameter 10-20 nm)” manufactured by Nissan Chemical Co., Ltd. “Snowtex-40 (particle diameter 10-20 nm)”, “Snowtex-N (particle diameter 10-20 nm)”, “Snowtex-S (particle diameter 8-11 nm)”, “Snowtex-XS (particle diameter) 4-6 nm) ".

  Colloidal silica having an average particle size of 20 nm or less is particularly preferable because it can be further improved in strength while maintaining the porosity of the layer to be formed, when used in combination with the aforementioned necklace-shaped colloidal silica.

  The ratio of colloidal silica / necklace-like colloidal silica having an average particle size of 20 nm or less is preferably in the range of 95/5 to 5/95, more preferably in the range of 70/30 to 20/80, and 60/40. A range of ˜30 / 70 is more preferred.

  In the present invention, porous metal oxide particles having a particle size of less than 1 μm can be contained as a porous material having a hydrophilic layer matrix structure.

(Porous metal oxide particles)
As the porous metal oxide particles, the following porous silica, porous aluminosilicate particles, or zeolite particles can be preferably used.

(Porous silica, porous silica, porous aluminosilicate particles)
The porous silica particles are generally produced by a wet method or a dry method. In the wet method, the gel obtained by neutralizing the aqueous silicate solution can be obtained by drying and pulverizing, or by pulverizing the precipitate deposited by neutralization. In the dry method, silicon tetrachloride is burned together with hydrogen and oxygen to obtain silica. These particles can be controlled in their porosity and particle size by adjusting the production conditions. As the porous silica particles, those obtained from a wet gel are particularly preferable.

  The porous aluminosilicate particles are produced, for example, by the method described in JP-A-10-71764. That is, amorphous composite particles synthesized by hydrolysis using aluminum alkoxide and silicon alkoxide as main components. The ratio of alumina to silica in the particles can be synthesized in the range of 1: 4 to 4: 1. In addition, those produced as composite particles of three or more components by adding an alkoxide of another metal during production can also be used in the present invention. These composite particles can also control the porosity and particle size by adjusting the production conditions.

  The porosity of the particles is preferably 0.5 ml / g or more in terms of pore volume, more preferably 0.8 ml / g or more, and further preferably 1.0 to 2.5 ml / g. preferable. The pore volume is closely related to the water retention of the coating film. The larger the pore volume, the better the water retention, the less likely to get dirty during printing, and the greater the water volume latitude, but more than 2.5 ml / g When it becomes large, the particles themselves become very brittle, so that the durability of the coating film is lowered. Conversely, if the pore volume is less than 0.5 ml / g, the printing performance may be slightly insufficient.

(Measurement method of pore volume)
Here, the pore volume is measured by using Autosorb-1 (manufactured by Cantachrome) and assuming that the voids of the powder are filled with nitrogen by nitrogen adsorption measurement using a constant volume method. Thus, the relative pressure is calculated from the nitrogen adsorption amount at 0.998.

(Zeolite particles)
Zeolite is a crystalline aluminosilicate, and is a porous body having regular three-dimensional network voids having a pore diameter of 0.3 nm to 1 nm.

  Further, the hydrophilic layer matrix structure constituting the hydrophilic layer can contain layered clay mineral particles. Examples of the layered mineral particles include kaolinite, halloysite, talc, smectite (montmorillonite, beidellite, hectorite, sabonite, etc.), clay minerals such as vermiculite, mica (mica), chlorite, hydrotalcite, layered polysilicic acid. Examples thereof include salts (kanemite, macatite, ialite, magadiite, kenyaite, etc.). In particular, the higher the charge density of the unit layer (unit layer), the higher the polarity and the higher the hydrophilicity. The charge density is preferably 0.25 or more, more preferably 0.6 or more. Examples of the layered mineral having such a charge density include smectite (charge density 0.25 to 0.6; negative charge), vermiculite (charge density 0.6 to 0.9; negative charge) and the like. In particular, synthetic fluoromica is preferable because it can be obtained with stable quality such as particle size. Further, among the synthetic fluorine mica, those that are swellable are preferable, and those that are free swell are more preferable.

  Also used are intercalation compounds of the above-mentioned layered minerals (pillar crystals, etc.), those subjected to ion exchange treatment, and those subjected to surface treatment (silane coupling treatment, compounding treatment with organic binder, etc.) can do.

  As the size of the flat lamellar mineral particles, the average particle diameter (maximum length of the particles) is less than 1 μm in the state of being contained in the layer (including the case where the swelling process and the dispersion peeling process have been performed). The aspect ratio is preferably 50 or more. When the particle size is in the above range, the continuity and flexibility in the planar direction, which are the characteristics of the thin layered particles, are imparted to the coating film, and it is difficult for cracks to occur, and a tough coating film can be obtained in a dry state. Moreover, in the coating liquid containing many particulate matters, sedimentation of particulate matter can be suppressed by the thickening effect of the layered clay mineral. When the particle diameter is larger than the above range, the coating film may be non-uniform, and the strength may be locally reduced. On the other hand, when the aspect ratio is not more than the above range, the number of tabular grains with respect to the addition amount is reduced, the viscosity is insufficient, and the effect of suppressing sedimentation of the particulate matter is reduced.

  The content of the layered mineral particles is preferably 0.1 to 30% by mass, and more preferably 1 to 10% by mass based on the entire layer. In particular, swellable synthetic fluorinated mica and smectite are preferable because they are effective even when added in a small amount. The layered mineral particles may be added as a powder to the coating solution, but in order to obtain a good degree of dispersion even with a simple preparation method (no need for a dispersion step such as media dispersion), the layered mineral particles are used alone. It is preferable to prepare the gel swollen in water and add it to the coating solution.

A silicate aqueous solution can also be used as the other additive material in the hydrophilic layer matrix constituting the hydrophilic layer. Alkali metal silicates such as silicate Na, silicate K, and silicate Li are preferred, and the SiO ₂ / M ₂ O ratio is in a range where the pH of the entire coating solution does not exceed 13 when silicate is added. It is preferable to select such that the inorganic particles are not dissolved.

  Further, an inorganic polymer or an organic-inorganic hybrid polymer by a so-called sol-gel method using a metal alkoxide can also be used. The formation of an inorganic polymer or an organic-inorganic hybrid polymer by the sol-gel method is described in, for example, “Application of the sol-gel method” (Sakuo Sakuo / Agne Jofusha) or is described in this document. Known methods described in the cited documents can be used.

  In the present invention, a water-soluble resin may be contained. Examples of the water-soluble resin include polysaccharides, polyethylene oxide, polypropylene oxide, polyvinyl alcohol, polyethylene glycol (PEG), polyvinyl ether, styrene-butadiene copolymer, conjugated diene polymer latex of methyl methacrylate-butadiene copolymer. Examples thereof include resins such as acrylic polymer latex, vinyl polymer latex, polyacrylamide, and polyvinylpyrrolidone. As the water-soluble resin used in the present invention, it is preferable to use a polysaccharide.

  As polysaccharides, starches, celluloses, polyuronic acids, pullulans and the like can be used, but cellulose derivatives such as methyl cellulose salts, carboxymethyl cellulose salts, hydroxyethyl cellulose salts are particularly preferable, and sodium salts and ammonium salts of carboxymethyl cellulose are preferable. More preferred. This is because an effect of forming the surface shape of the hydrophilic layer in a preferable state can be obtained by including the polysaccharide in the hydrophilic layer.

  The surface of the hydrophilic layer preferably has a concavo-convex structure with a pitch of 0.1 to 20 μm like the aluminum grain of the PS plate, and this concavo-convex improves water retention and image area retention. Such a concavo-convex structure can be formed by adding an appropriate amount of a filler having an appropriate particle size to the hydrophilic layer matrix. However, the above-mentioned alkaline colloidal silica and the above-mentioned water-soluble solution are added to the hydrophilic layer coating solution. It is preferable that a structure having better printability can be obtained by forming a phase separation when the hydrophilic polysaccharide is applied and dried.

  The shape of the concavo-convex structure (such as pitch and surface roughness) is determined by the type and amount of alkaline colloidal silica, the type and amount of water-soluble polysaccharides, the type and amount of other additives, the solid content concentration of the coating solution, and the wetness. It is possible to appropriately control the film thickness, drying conditions, and the like.

  In the present invention, the water-soluble resin added to the hydrophilic matrix structure part is preferably present in a state where at least a part thereof is water-soluble and can be eluted in water. This is because even if it is a water-soluble material, when it is cross-linked by a cross-linking agent or the like and becomes insoluble in water, its hydrophilicity is lowered and printability may be deteriorated. Further, it may further contain a cationic resin. Examples of the cationic resin include polyalkylene polyamines such as polyethylene amine and polypropylene polyamine or derivatives thereof, tertiary amino groups and quaternary ammonium groups. Examples thereof include acrylic resin and diacrylamine. The cationic resin may be added in the form of fine particles, and examples thereof include a cationic microgel described in JP-A-6-161101.

  In addition, the coating liquid used for coating the hydrophilic layer can contain a water-soluble surfactant for the purpose of improving the coatability, and a Si-based or F-based surfactant can be added. Although it can be used, it is particularly preferable to use a surfactant containing Si element because there is no fear of causing printing stains. The content of the surfactant is preferably 0.01 to 3% by mass, more preferably 0.03 to 1% by mass of the entire hydrophilic layer (solid content as the coating solution).

  The hydrophilic layer can contain a phosphate. In the present invention, since the hydrophilic layer coating solution is preferably alkaline, the phosphate is preferably added as trisodium phosphate or disodium hydrogen phosphate. By adding phosphate, the effect of improving the mesh opening at the time of printing can be obtained. The addition amount of phosphate is preferably 0.1 to 5% by mass, and more preferably 0.5 to 2% by mass as an effective amount excluding hydrate.

  Examples of the metal of the metal plate used as the substrate include iron, stainless steel, and aluminum. Aluminum or an aluminum alloy (hereinafter referred to as aluminum) is particularly preferable from the relationship between specific gravity and rigidity.

  The aluminum substrate is preferably used after being subjected to a roughening treatment, an anodizing treatment or the like in order to form a hydrophilic surface.

  The aluminum substrate is preferably subjected to a degreasing treatment in order to remove the rolling oil on the aluminum surface prior to the roughening treatment. As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used. In addition, an alkaline aqueous solution such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium phosphate or the like can be used for the degreasing treatment. When an alkaline aqueous solution is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the degreasing treatment can be removed.

  The roughening of the substrate can be performed by chemical roughening treatment, mechanical roughening, or roughening treatment appropriately combining them.

  Following the roughening treatment, it is preferable to perform an anodizing treatment.

  There is no restriction | limiting in particular in the method of an anodizing process, A well-known method can be used.

  The anodized base material may be subjected to a sealing treatment as necessary. These sealing treatments can be performed using known methods such as hot water treatment, boiling water treatment, water vapor treatment, dichromate aqueous solution treatment, nitrite treatment, ammonium acetate treatment.

  In addition, the anodized base material can be appropriately subjected to a surface treatment other than the sealing treatment. Examples of the surface treatment include known treatments such as silicate treatment, phosphate treatment, various organic acid treatments, PVPA treatment, and boehmite treatment. Further, an organic acid treatment such as citric acid may be performed following the treatment with an aqueous solution containing a bicarbonate described in JP-A-8-314157 or the treatment with an aqueous solution containing a bicarbonate.

  Moreover, in order to improve adhesiveness with a coating layer, it is preferable to perform an easily bonding process and undercoat layer application | coating to an application surface. For example, a method of dipping in a liquid containing a coupling agent such as a silicate or a silane coupling agent, or applying a liquid and then sufficiently drying may be mentioned.

(Ink receiving layer)
The ink receiving layer according to the present invention is a layer provided on a hydrophilic surface of a substrate having a hydrophilic surface, and is a layer capable of absorbing actinic ray curable ink and can be removed by development processing. It is. The layer that can be removed by the development treatment is preferably a layer that can be developed on a printing press. A layer that can be developed on a printing press is a layer that can remove a portion that becomes a non-image area by supplying dampening water or dampening water and printing ink onto a printing plate material and printing on the printing press. is there.

  As the ink receiving layer, a layer containing a water-soluble resin used for the hydrophilic layer is advantageously used.

  The thickness of the ink receiving layer is preferably 0.1 μm to 5.0 μm, particularly preferably 0.3 μm to 1.0 μm.

(Image forming layer)
The image forming layer according to the present invention is a layer that can be developed on a printing press. For example, as described in JP-A-8-507727 and JP-A-6-186750 recorded by thermal laser recording or thermal head recording. An image forming layer used for printing plate materials of ablation type, heat fusion image layer on-machine development type and heat fusion transfer type as described in JP-A-9-123387 can be used.

  A layer that can be developed on a printing press is a portion that forms a non-image area by forming an image and then supplying dampening water or dampening water and printing ink onto the printing plate material and printing on the printing press. Is a layer that can be removed.

  The image forming layer is a layer having a lipophilic component, and is particularly preferably a layer containing a lipophilic component and a water-soluble binder. The oleophilic component means that the image forming layer can become printing ink receptive when the image forming layer is printed, and is particularly preferably included in the image forming layer in the form of particles.

  As the particulate lipophilic component, thermoplastic polymer particles are preferably used, and examples thereof include lipophilic heat-fusible particles and heat-fusible particles.

(Hot-melting particles)
Examples of the heat-meltable particles that can be used in the image forming layer include particles formed of a material that has a low viscosity when melted and is generally classified as a wax among thermoplastic materials.

  The physical properties are preferably a softening point of 40 ° C. or higher and 120 ° C. or lower, a melting point of 60 ° C. or higher and 150 ° C. or lower, from the viewpoint of storage stability and ink inking property, and a softening point of 40 ° C. or higher and 100 ° C. or lower. More preferably, it is not higher than ° C.

  Examples of materials that can be used include paraffin, polyolefin, polyethylene wax, microcrystalline wax, and fatty acid wax. These have a molecular weight of about 800 to 10,000, and in order to facilitate emulsification, these waxes can be oxidized to introduce polar groups such as a hydroxyl group, an ester group, a carboxyl group, an aldehyde group, and a peroxide group. Furthermore, in order to lower the softening point and improve workability, these waxes are used, for example, stearamide, linolenamide, laurylamide, myristamide, hardened bovine fatty acid amide, palmitoamide, oleic acid amide, rice sugar fatty acid amide. It is also possible to add coconut fatty acid amides or methylolated products of these fatty acid amides, methylene bisstellaramide, ethylene bisstellaramide and the like. Coumarone-indene resin, rosin-modified phenol resin, terpene-modified phenol resin, xylene resin, ketone resin, acrylic resin, ionomer, and copolymers of these resins can also be used.

  Among these, it is preferable to contain any of polyethylene, microcrystalline, fatty acid ester, and fatty acid.

  These heat-meltable particles are preferably dispersible in water, and the average particle diameter is preferably 0.01 to 10 μm, more preferably 0.05 to 3 μm from the viewpoint of on-press developability. .

  In order to disperse these heat-meltable particles in water, it is preferable to use a nonionic surfactant, an anionic surfactant, a cationic surfactant, or a polymer surfactant. By using these compounds, it is possible to stabilize an aqueous dispersion of heat-meltable fine particles, and to obtain a uniform coated product having no failure.

  Further, the composition of the heat-meltable particles may be continuously changed between the inside and the surface layer, or may be coated with a different material. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the heat-meltable particle | grains in an image forming layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is still more preferable.

(Heat-bonding particles)
Examples of the heat-fusible particles include thermoplastic hydrophobic polymer particles, and there is no specific upper limit for the softening temperature of the thermoplastic hydrophobic polymer particles. It is preferable that the temperature is lower than the decomposition temperature. Moreover, it is preferable that the weight average molecular weight (Mw) of a high molecular weight polymer is the range of 10,000-1,000,000.

  Specific examples of the polymer constituting the thermoplastic hydrophobic polymer particles include, for example, diene (co) polymers such as polypropylene, polybutadiene, polyisoprene, and ethylene-butadiene copolymer, and styrene-butadiene. Synthetic rubbers such as copolymers, methyl methacrylate-butadiene copolymers, acrylonitrile-butadiene copolymers, polymethyl methacrylate, methyl methacrylate- (2-ethylhexyl acrylate) copolymers, methyl methacrylate-methacrylic acid copolymers, Methyl acrylate- (N-methylolacrylamide) copolymer, (meth) acrylic acid ester such as polyacrylonitrile, (meth) acrylic acid (co) polymer, polyvinyl acetate, vinyl acetate-vinyl propionate copolymer, acetic acid Vinyl-ethylene copolymer weight Vinyl ester (co) polymer such as a body, vinyl acetate - (2-ethylhexyl acrylate) copolymers, polyvinyl chloride, polyvinylidene chloride, polystyrene and copolymers thereof. Of these, (meth) acrylic acid esters, (meth) acrylic acid (co) polymers, vinyl ester (co) polymers, polystyrene, and synthetic rubbers are preferably used.

  The thermoplastic hydrophobic polymer particles may be made of a polymer polymer polymerized by any known method such as emulsion polymerization, suspension polymerization, solution polymerization, and gas phase polymerization. As a method for making a polymer polymer polymerized by a solution polymerization method or a gas phase polymerization method into a fine particle, a solution is sprayed in an inert gas in an organic solvent of the polymer polymer and dried to make a fine particle, Examples include a method in which a high molecular polymer is dissolved in an organic solvent immiscible with water, this solution is dispersed in water or an aqueous medium, and the organic solvent is distilled off to form fine particles.

  Further, in any of the methods, the heat-meltable particles and the heat-fusible particles may be used as a dispersant or a stabilizer, for example, when polymerized or finely divided, for example, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, polyethylene A surfactant such as glycol or a water-soluble resin such as polyvinyl alcohol may be used. Further, triethylamine, triethanolamine or the like may be contained.

  The heat-fusible particles are preferably dispersible in water, and the average particle diameter is preferably 0.01 to 10 μm, more preferably 0.1 to 10 μm from the viewpoint of on-press developability and resolution. 3 μm.

  Further, the composition of the heat fusible particles may be continuously changed between the inside and the surface layer, or may be coated with a different material. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the heat-fusible particle | grains in an image forming layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is still more preferable.

(Water-soluble binder)
Examples of the water-soluble binder that can be used in the image forming layer include polysaccharides, polyethylene oxide, polypropylene oxide, polyvinyl alcohol, polyethylene glycol (PEG), polyvinyl ether, styrene-butadiene copolymer, and methyl methacrylate-butadiene copolymer. Examples thereof include conjugated diene polymer latex, acrylic polymer latex, vinyl polymer latex, polyacrylamide, polyacrylic acid or salts thereof, and resins such as polyvinyl pyrrolidone. Among them, it is preferable to use polyacrylic acid or a salt or polysaccharide thereof that does not deteriorate the printing performance.

The dry coating mass of the image forming layer is preferably 0.1 to 1.5 g / m ² , more preferably 0.15 to 1.0 g / m ² .

(Photothermal conversion material)
The image forming layer according to the present invention may contain a photothermal conversion material.

  An infrared absorbing dye or pigment can be used as the photothermal conversion material.

(Infrared absorbing dye)
Examples of infrared absorbing dyes include organic dyes such as cyanine dyes, croconium dyes, polymethine dyes, azurenium dyes, squalium dyes, thiopyrylium dyes, naphthoquinone dyes, anthraquinone dyes, which are general infrared absorbing dyes. Examples thereof include compounds, phthalocyanine-based, naphthalocyanine-based, azo-based, thioamide-based, dithiol-based, and indoaniline-based organometallic complexes.

  Specifically, JP-A-63-139191, JP-A-64-33547, JP-A-1-160683, JP-A-280750, JP-A-1-293342, JP-A-2-2074, JP-A-3-26593, 3-30991, 3-34891, 3-36093, 3-36094, 3-36095, 3-42281, 3-97589, 3-103476, 7 -43851, 7-102179, JP-A-2001-117201, and the like. These can be used alone or in combination of two or more.

  Examples of the pigment include carbon, graphite, metal, metal oxide and the like.

  As carbon, furnace black or acetylene black is particularly preferable. The particle size (d50) is preferably 100 nm or less, and more preferably 50 nm or less.

  As the graphite, fine particles having a particle size of 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less can be used.

  As the metal, any metal can be used as long as the particle diameter is 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less. The shape may be any shape such as a spherical shape, a piece shape, or a needle shape. Colloidal metal fine particles (Ag, Au, etc.) are particularly preferable.

As the metal oxide, a material that is black in the visible light region or a material that is conductive or that is a semiconductor can be used. Examples of the material exhibiting black color in the visible light region include black iron oxide (Fe ₃ O ₄ ) and black mixed metal oxides containing two or more of the aforementioned metals. The metal oxide is a black complex metal oxide composed of two or more kinds of metal oxides. Specifically, it is a composite metal oxide composed of two or more metals selected from Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sb, and Ba. These can be produced by the methods disclosed in JP-A-8-27393, 9-25126, 9-237570, 9-241529, and 10-231441. The composite metal oxide that can be used in the present invention is particularly preferably a Cu-Cr-Mn-based or Cu-Fe-Mn-based composite metal oxide. In the case of a Cu—Cr—Mn system, it is preferable to perform the treatment disclosed in JP-A-8-27393 in order to reduce the elution of hexavalent chromium. These composite metal oxides are colored with respect to the amount added, that is, have good photothermal conversion efficiency. These composite metal oxides preferably have an average primary particle size of 1 μm or less, and more preferably have an average primary particle size in the range of 0.01 to 0.5 μm. When the average primary particle diameter is 1 μm or less, the photothermal conversion ability with respect to the addition amount becomes better, and when the average primary particle diameter is within the range of 0.01 to 0.5 μm, the photothermal conversion ability with respect to the addition amount is obtained. Better. However, the photothermal conversion ability with respect to the addition amount is greatly affected by the degree of dispersion of the particles, and the better the dispersion, the better. Therefore, it is preferable to disperse these composite metal oxide particles by a known method separately before adding them to the layer coating solution to prepare a dispersion (paste). An average primary particle size of less than 0.01 is not preferable because dispersion becomes difficult. A dispersing agent can be appropriately used for the dispersion. The addition amount of the dispersant is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass with respect to the composite metal oxide particles. Although the kind of dispersing agent is not specifically limited, it is preferable to use Si type surfactant containing Si element.

Examples of materials that have conductivity or are semiconductors include reduced Sb-doped SnO ₂ (ATO), Sn-added In ₂ O ₃ (ITO), TiO ₂ , and TiO ₂ . Examples thereof include TiO (titanium oxynitride, generally titanium black). Further, it is also possible to use those obtained by coating the core material _{(BaSO 4, TiO 2, 9Al} 2 O 3 · 2B 2 O, K 2 O · nTiO 2 , etc.) in these metal oxides. These particle sizes are 0.5 μm or less, preferably 100 nm or less, and more preferably 50 nm or less.

  The addition amount of these photothermal conversion materials is preferably 0.1 to 50% by mass, more preferably 1 to 30% by mass, and particularly preferably 3 to 25% by mass with respect to the image forming layer.

  In the present invention, when the image forming droplet is the actinic ray curable ink, the printing plate material has a printing plate material or a hydrophilic surface which is a substrate having the hydrophilic surface. It is particularly preferable to use a printing plate material having an ink receiving layer on a substrate.

  As another preferred embodiment of the present invention, there is a case where the image forming droplet is a droplet containing an adhesive component.

  When the image forming droplet is a droplet containing an adhesive component, a printing plate material having an image forming layer containing a lipophilic component on a substrate having a hydrophilic surface may be used as the printing plate material. preferable.

(Liquid containing adhesive component)
In the present invention, an image is formed by supplying a liquid containing an adhesive component on the image forming layer of the printing plate material in an image-like manner. The liquid containing the adhesive component according to the present invention is supplied onto the image forming layer and penetrates into the image forming layer.

  Adhesive component refers to an image forming layer, that is, an image portion, which has penetrated into the image forming layer and then increased the adhesive force between the image forming layer and the hydrophilic layer surface of the base material and supplied with a liquid containing the adhesive component. It can be prevented from being removed by development. Adhesive strength can be increased by the presence of the adhesive component at the interface between the substrate surface and the image forming layer. Further, the adhesion between the oleophilic component and the water-soluble binder in the image forming layer is also increased, so that it is more difficult to remove by on-press development.

  Adhesive components include casein, natural latex, starch, gelatin and other natural adhesive components, acrylic acid and its derivatives, acrylic resin, polyester resin, copolymer resin of α-olefin and maleic anhydride, urethane resin, hydroxyl group at the end Mixture of polyol and polyisocyanate with ethylene, ethylene / vinyl acetate resin, epoxy resin prepolymer, vinyl chloride resin, vinyl acetate resin, cyanoacrylate, silicone, styrene / butadiene rubber copolymer, nitrocellulose, phenol resin, butyral resin, etc. Of these, urethane resins, acrylic resins, polyester resins, and butyral resins are preferably used, and polyester resins and butyral resins are more preferred from the viewpoint of printing durability, and in particular, butyral resins. Preferred.

  As content with respect to the whole liquid of an adhesive component, 0.5-80 mass% is preferable, More preferably, it is 2-50 mass%, Especially 2-25 mass% is preferable.

  As the solvent of the liquid containing the adhesive component, it is preferable to use various solvents in which the adhesive component dissolves. Specific examples of the solvent include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol), polyhydric alcohols (eg, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene). Glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol), glycol ethers (eg, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl) Ether, diethylene glycol monobutyl ether, ether Lenglycol monomethyl acetate, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, ethylene glycol monophenyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol ethyl methyl Ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol Dimethyl ether), cyclic esters (eg, propylene carbonate, β-propiolactone, β-butyrolactone, α-methyl-β-butyrolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε-caprolactone, γ -Caprolactone, γ-heptanolactone).

  The above solvent is preferably supplied from the image forming layer and then removed from the image forming layer by volatilization or the like. For example, a mixed solvent of dipropylene glycol monomethyl ether and diethylene glycol diethyl ether, a mixture of diethylene glycol dimethyl ether and propylene carbonate A solvent, etc. are preferably used.

  As content with respect to the whole liquid of this solvent, 20-99 mass% is preferable, More preferably, it is 50-98 mass%.

  In the present invention, an aspect in which the liquid droplet containing the adhesive component is a liquid droplet by an ink jet recording method is a preferable aspect.

  Hereinafter, the case where the liquid containing the adhesive component is an inkjet ink used in the inkjet recording method will be described.

  When supplying a liquid containing an adhesive component in an image-like manner by an ink jet recording method, the preferred viscosity of the liquid containing the adhesive component is 2 to 100 mPa · s at 25 ° C., more preferably 4 to 80 mPa · s. It is.

  In addition, when the liquid is supplied in an image-like manner by the ink jet recording method, it is preferable that the liquid containing the adhesive component contains a colorant from the viewpoint of visible image quality, and various known pigments or dyes can be used as the colorant. .

(Pigment)
As the pigment, conventionally known organic and inorganic colored pigments can be preferably used. Examples of the colored pigment include azo pigments such as azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, perylene and perylene pigments, Polycyclic pigments such as anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, quinophthaloni pigments, dye lakes such as acid dye lakes, nitro pigments, nitroso pigments, aniline black, daylight fluorescence Examples thereof include organic pigments such as pigments and inorganic pigments such as carbon black. In the present invention, carbon black is particularly preferable from the viewpoint of visible image quality.

(Dispersant)
In order to stably disperse the pigment in the inkjet ink, the following water-soluble resin is preferably used as the water-soluble polymer dispersant.

  As the water-soluble resin, styrene-acrylic acid-acrylic acid alkyl ester copolymer, styrene-acrylic acid copolymer, styrene-maleic acid copolymer, styrene-maleic acid-acrylic acid alkyl ester copolymer are preferably used. Styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid alkyl ester copolymer, styrene-maleic acid half ester copolymer, vinyl naphthalene-acrylic acid copolymer, vinyl naphthalene-maleic acid copolymer It is a water-soluble resin such as.

  The content of the water-soluble resin with respect to the total amount of the ink is preferably 0.1 to 10% by mass, and more preferably 0.3 to 5% by mass. Two or more of these water-soluble resins can be used in combination.

  The average particle size of the pigment dispersion used in the inkjet ink is preferably 500 nm or less, more preferably 200 nm or less, more preferably 10 nm or more and 200 nm or less, more preferably 10 nm or more and 150 nm or less, from the viewpoint of the storage stability of the ink. Particularly preferred.

  Various methods such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used as a method for dispersing the pigment.

(dye)
There is no restriction | limiting in particular as dye, Water-soluble dyes, such as an acid dye, a direct dye, and a reactive dye, a disperse dye, etc. are mentioned.

(Water-soluble dye)
Examples of water-soluble dyes include azo dyes, methine dyes, azomethine dyes, xanthene dyes, quinone dyes, phthalocyanine dyes, triphenylmethane dyes, diphenylmethane dyes, and the like.

(Surfactant)
The inkjet ink may contain a surfactant, which includes alkyl sulfates, alkyl ester sulfates, dialkyl sulfosuccinates, alkyl naphthalene sulfonates, alkyl phosphates, polyoxyalkylene alkyl ether phosphates. , Anionic surfactants such as fatty acid salts, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, acetylene glycols, polyoxyethylene-polyoxypropylene block copolymers, glycerin esters , Surfactants such as sorbitan esters, polyoxyethylene fatty acid amides and amine oxides, and cationic surfactants such as alkylamine salts and quaternary ammonium salts.

(Various additives)
The ink-jet ink can contain other conventionally known additives. For example, optical brighteners, antifoaming agents, lubricants, preservatives, thickeners, antistatic agents, matting agents, water-soluble polyvalent metal salts, acid bases, pH adjusters such as buffer solutions, antioxidants, surface tension It is a regulator, a specific resistance regulator, a rust preventive agent and the like.

(Method of forming image by inkjet recording method)
In an image forming method using droplets by an ink jet recording method, first, an ink jet ink is supplied to a printer head having ink discharge nozzles of a printer for an ink jet recording method. Dispense onto material. Thereafter, in order to dry the discharged droplets, it is preferable to perform actinic ray irradiation treatment with ultraviolet rays, infrared rays, or the like, or heat treatment.

  The inkjet ink preferably has a viscosity at 25 ° C. adjusted to 4 to 80 mPa · s from the viewpoint of ejection stability. The ink-jet ink preferably has a conductivity of 10 μS / cm or less in the piezo head and does not cause electrical corrosion inside the head. Further, in the continuous type, it is necessary to adjust the electric conductivity by the electrolyte. In this case, it is preferable to adjust the electric conductivity to 0.5 mS / cm or more.

  In the present invention, when supplying droplets containing an adhesive component, after discharging from the nozzle image-wise onto the surface of the image forming layer as described above, a treatment such as drying may be performed once, but drying is performed. It is preferable to supply droplets a plurality of times in succession before, and supply a plurality of times and then perform a treatment such as drying.

  The number of times of image-like supply is preferably 2 to 8 times, particularly preferably 2 to 4 times.

  As a method of supplying ink, after supplying once, supplying based on the same image again and repeating this, a method by batch processing, droplets are subdivided at the time of ejection, and droplets subdivided at the same place continuously There is a supply method, a method of preparing multiple sets of ink heads, and supplying them continuously from different heads to the same part of the image, etc., but droplets are subdivided at the time of ejection, and subdivided droplets are continuous at the same place In particular, the supply method is preferably used.

(Preparation method of printing plate)
In the printing plate preparation method of the present invention, if necessary, development on a printing press is performed to prepare a printing plate. That is, when the printing plate material is a printing plate material having an ink receiving layer on a substrate having a hydrophilic surface, an image forming layer containing an oleophilic component is formed on the substrate having a printing plate material on a hydrophilic surface. In the case of the printing plate material having, it is developed on a printing machine to produce a printing plate.

  As a printing machine used in the method for producing a printing plate of the present invention, a general lithographic printing machine is used. The lithographic printing machine has a dampening water supply device and a printing ink supply device.

  Development on the printing press according to the present invention is performed by supplying dampening water or dampening water and printing ink onto the printing plate material on which an image is formed.

  The imaged printing plate material is directly attached to the plate cylinder of the printing press, or the image forming is performed after the printing plate material is attached to the plate cylinder of the printing press, and the water supply roller and / or ink is rotated while rotating the plate cylinder. The non-image portion of the image forming layer can be removed by bringing the supply roller into contact with the printing plate material.

  The development on the printing press according to the present invention can be carried out in a normal printing sequence using a PS plate, and it is a preferred embodiment that it is a process performed by so-called on-press development processing.

  The plate making apparatus used in the printing plate preparation method of the present invention is an apparatus in which an ink jet recording apparatus and a planographic printing machine are arranged in series, or an apparatus in which an ink jet recording apparatus is mounted on the planographic printing machine.

  An apparatus in which an inkjet recording apparatus is mounted on a lithographic printing machine can attach a printing plate material to the lithographic printing machine, perform image formation on the printing machine, and can perform printing immediately after image formation. The ink jet recording apparatus or lithographic printing machine preferably has a drying device for drying the ink jet ink after image formation.

(ink)
The printing ink that can be used in the present invention may be any ink as long as it can be used for lithographic printing. Specifically, rosin-modified phenolic resin and vegetable oil (linseed oil, tung oil, soybean oil, etc.), Oil-based ink consisting of components such as petroleum solvents, pigments, oxidation polymerization catalysts (cobalt, manganese, lead, iron, zinc, etc.), and UV curing consisting of components such as acrylic oligomers, acrylic monomers, photopolymerization initiators, pigments, etc. Examples include UV inks of a type, and hybrid inks having both the properties of oil-based inks and the properties of UV inks.

(Dampening water)
As the fountain solution, a general fountain solution used for lithographic printing can be used.

  As the fountain solution, it is preferable to use a water-soluble organic solvent such as an alkylene glycol monoalkyl ether compound, a pH adjuster, an auxiliary agent for improving wettability, a water-soluble polymer compound, a chelating agent, a preservative, and the like.

(Preparation of image forming liquid (ink))
<Preparation of Inkjet Ink 1 (Actinic Light Curing Inkjet Ink)>
<< Preparation of pigment dispersion >>
[Preparation of Pigment Dispersion-1]
Each of the following compounds was placed in a stainless beaker and dissolved by heating and stirring for 1 hour while heating on a hot plate at 50 ° C.

Solsperse 24000GR (manufactured by Avicia, polymer dispersant, amine value 35.9 mg / g KOH) 5 parts OXT221 (oxetane compound produced by Toagosei Co., Ltd.) 84.2 parts Next, the above solution was cooled to room temperature, and then the following pigments were added thereto: Was added to a polypropylene container together with 100 g of zirconia beads having a diameter of 0.5 mm, and sealed with a paint shaker for 6 hours, and then the zirconia beads were removed to prepare pigment dispersion-1. I. Pigment Yellow 120 10 parts Benzimidazolone Derivative SY-1 0.8 part The following components are mixed in the following proportions in the above-described pigment dispersion, and the mixture is filtered through a 1.0 μm membrane filter to obtain an ink. Was prepared.

Pigment dispersion-1 30.0 parts OXT212 (Oxetane compound manufactured by Toagosei Co., Ltd.) 40.0 parts 1,2: 8,9 diepoxy limonene 27.0 parts Photoacid generator (SP-152: Triphenylsulfonium salt ( "Adekaoptomer SP-152" manufactured by Asahi Denka Co., Ltd.)) 0.5 part Surfactant (F475: Megafax F475 perfluoroalkyl group-containing acrylic oligomer (Dainippon Ink & Chemicals)) 0.02 part <Inkjet Adjustment of ink 2 (adjustment of ink containing adhesive component)>
A liquid containing the following components was stirred and mixed, and then filtered to prepare an ink containing an adhesive component.

Adhesive component: Butyral resin (S-REC BL-5Z (manufactured by Sekisui Chemical Co., Ltd.)) 5 parts Dipropylene glycol monomethyl ether 45 parts Diethylene glycol diethyl ether 50 parts Carbon black powder (MA-7 (manufactured by Mitsubishi Chemical Corporation)) 0.1 part (Preparation of printing plate material)
<Preparation of printing plate material 1 (base material having a hydrophilic surface)>
An aluminum plate (material 1050, tempered H16) having a thickness of 0.24 mm was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., degreased for 1 minute, and then washed with water.

  This degreased aluminum plate was neutralized by dipping in a 10% aqueous hydrochloric acid solution maintained at 25 ° C. for 1 minute, and then washed with water.

Next, this aluminum plate was subjected to electrolytic surface roughening at 25 ° C. for 30 seconds in an electrolytic solution condition of 60 A / dm ^{2 in} a 1.5% hydrochloric acid aqueous solution.

Thereafter, desmutting treatment was performed at 50 ° C. for 40 seconds in a 1% aqueous sodium hydroxide solution maintained at 50 ° C. The roughened aluminum plate subjected to desmut treatment was anodized in a 30% sulfuric acid solution at 25 ° C., a current density of 30 A / dm ² , and a voltage of 25 V for 30 seconds.

  Next, a sealing treatment was performed with a 0.1% aqueous ammonium acetate solution at 85 ° C. for 120 seconds.

  The above support was dipped in a 0.44% aqueous polyvinylphosphonic acid solution at 75 ° C. for 30 seconds, then washed with distilled water and dried with cold air at 25 ° C. to obtain a printing plate material 1.

<Preparation of printing plate material 2 (printing plate material having an image forming layer)>
<< Production of polyethylene terephthalate support >>
(Preparation of support 1)
Using terephthalic acid and ethylene glycol, a polyethylene terephthalate having IV (inherent viscosity) = 0.66 (measured in phenol / tetrachloroethane = 6/4 (mass ratio) at 25 ° C.) was obtained according to a conventional method.

  This is pelletized, dried at 130 ° C. for 4 hours, melted at 300 ° C., extruded from a T-die, rapidly cooled on a cooling drum at 50 ° C., and not yet thick enough to have an average film thickness of 175 μm after heat setting. A stretched film was prepared.

  With respect to the drawing temperature, the first drawing was stretched 1.3 times at 102 ° C. and the second drawing was longitudinally stretched 2.6 times at 110 ° C.

  Next, it was stretched 4.5 times at 120 ° C. with a tenter. Thereafter, the film was heat-fixed at 240 ° C. for 20 seconds and relaxed by 4% in the lateral direction at the same temperature.

  Thereafter, the chuck portion of the tenter was slit, knurled at both ends, cooled to 40 ° C., and wound at 47.1 N / m.

  A biaxially stretched polyethylene terephthalate film having a thickness of 190 μm was thus obtained. The glass transition temperature (Tg) of this biaxially stretched polyethylene terephthalate film was 79 ° C. The obtained polyethylene terephthalate film had a width (film formation width) of 2.5 m.

  The thickness distribution of the obtained support 1 was 3%.

《Preparation of underdrawn substrate》
One side of the film of the support 1 obtained above was subjected to corona discharge treatment under the condition of 0.05 kV · A · min / m ² , and the following << undercoating liquid c-1 >> Was applied at a dry film thickness of 0.06 μm, dried at 140 ° C., and then the following “undercoat coating solution d-1” was applied at a dry film thickness of 0.2 μm and then 140 ° C. And dried (undercoat surface B).

<< Undercoat coating liquid c-1; containing conductive compound >>
Copolymer polymer latex of styrene / glycidyl methacrylate / butyl acrylate (20/40/40) (solid content 30% by mass) 16.0 g
Copolymer polymer latex of styrene / butyl acrylate / hydroxymethyl methacrylate (25/45/30) (solid content 30% by mass) 4.0 g
SnO ₂ sol (solid content 10% by mass) 9.1 g
(Synthesis by the method described in Example 1 of JP-A-10-059720)
Anionic surfactant S-1 0.5g
Above, distilled water was added to make 1000 ml to obtain a coating solution.

<< Undercoat coating liquid d-1 >>
Modified polyester A (see below, solid content 18% by mass) 215.0 g
Anionic surfactant S-1 0.4 g
Spherical silica Seahoster KE-P50 (made by Nippon Shokubai Co., Ltd.) 0.3g
Distilled water was added to make 1000 ml, and a coating solution having a solid content concentration of 0.5 mass% was obtained.

(Modified polyester A)
Aqueous dispersion of water-soluble copolyester component / acrylic component (80/20) The water-soluble copolyester component was terephthalic acid / isophthalic acid / cyclohexanedicarboxylic acid / 5-sulfo-isophthalic acid dimethyl sodium salt (40/38/14 / 8) Mixed component of ethylene glycol The acrylic component is a copolymer latex of methyl methacrylate / ethyl acrylate / glycidyl methacrylate (53/37/10), and then 0.05 kV · A · min / m ² on the opposite surface. The following << undercoating liquid a >> is applied so as to have a dry film thickness of 0.25 [mu] m, and the following <undercoating liquid b liquid> is then applied to a dry film thickness of 0.06 [mu] m. And then dried at 140 ° C. (undercoating surface A).

These were heat-treated at 125 ° C. for 2 minutes to produce a substrate sample with an underdrawn << Undercoat coating liquid a >>
Copolymer latex of styrene / glycidyl methacrylate / butyl acrylate (20/40/40) (solid content 30% by mass) 56.3 g
Copolymer latex of styrene / glycidyl methacrylate / butyl acrylate (59.7 / 39.8 / 0.5) (solid content 30% by mass) 210 g
Anionic surfactant S-1 (2% aqueous solution) 30 g
Distilled water was added to make 1000 ml, and the undercoat coating solution a was obtained.

<< Undercoat coating liquid b >>
Modified polyester B (see below, solid content 21.7% by mass) 31 g
Anionic surfactant S-1 5.7 g
Spherical silica matting agent Seahoster KE-P50 (manufactured by Nippon Shokubai Co., Ltd.)
1.9g
An aqueous solution obtained by adding 250 ppm of F-1 to ethylene copolymer polyvinyl alcohol (RS2117 manufactured by Kuraray Co., Ltd.) (solid content 5 mass%) 57.7 g
Hardener H-1 (solid content 0.5% by weight aqueous solution) 50 g
Distilled water was added to make 1000 ml as above, and the undercoat coating solution b was obtained.

(Modified polyester B)
Aqueous dispersion of water-soluble copolyester component / acrylic component (64/36) The water-soluble copolyester component was terephthalic acid / isophthalic acid / cyclohexanedicarboxylic acid / 5-sulfo-isophthalic acid dimethyl sodium salt (40/38/14 / 8) Mixed component of ethylene glycol The acrylic component is a copolymer latex of styrene / glycidyl methacrylate / butyl acrylate / acetoacetoxyethyl methacrylate (39.5 / 40/20 / 0.5).

《Heat treatment of undercoated support》
A low tension heat treatment was performed at 180 ° C. for 1 minute at a tension of 2 hPa on the substrate with the underdrawn after slitting to a width of 1.25 m.

<Preparation of printing plate material>
Immediately before coating the hydrophilic layer, the substrate with the subbing was heat-treated at 100 ° C. for 30 seconds and dried, and covered with a moisture-proof sheet to prevent moisture in the air from entering.

  When a moisture content was measured by sampling a part of the support, it was 0.2% by mass. Immediately after removing the sheet, a hydrophilic layer was applied.

  Using the coating solution for hydrophilic layer 1 shown in Table 1 (the preparation method is shown below) and the coating solution for hydrophilic layer 2 shown in Table 2 (the preparation method is shown below), It applied on the drawing surface A using the wire bar.

  Each of the hydrophilic layers 1 and the hydrophilic layers 2 was applied on the undercoated substrate in the order of the hydrophilic layer 1 using a wire bar, dried at 120 ° C. for 3 minutes, and then subjected to heat treatment at 60 ° C. for 48 hours.

  Thereafter, the image-forming functional layer coating solution shown in Table 3 (preparation method is shown below) was applied using a wire bar, and the coating solution for the outermost outer coating layer shown in Table 4 (preparation method is shown below). Using, a wire bar was applied on the undercoating surface B of the subextracted substrate and dried at 50 ° C. for 3 minutes.

  Thereafter, each printing plate material was subjected to seasoning at 50 ° C. for 48 hours.

[Preparation of coating solution for hydrophilic layer 1]
Each material shown in Table 1 was sufficiently stirred and mixed using a homogenizer, then mixed and filtered with the composition shown in Table 1, diluted and dispersed with pure water to prepare a coating solution for hydrophilic layer 1.

In addition, the detail of each raw material is as having described in Table 1, and the numerical value in a table | surface represents the mass of the amount of solid content per m < ² >.

[Preparation of coating solution for hydrophilic layer 2]
Each material shown in Table 2 was sufficiently stirred and mixed using a homogenizer, then mixed and filtered with the composition shown in Table 2, diluted with pure water, and dispersed to prepare a coating solution for hydrophilic layer 2.

In addition, the detail of each raw material is as having described in Table 2, and the numerical value in a table | surface represents the mass of the amount of solid content per m < ² >.

(Preparation of image forming functional layer coating solution)
Table 3 shows details of the material of the image forming functional layer coating solution. An image forming functional layer coating solution was prepared by diluting and dispersing with pure water.

The numerical values in the table represent the mass of the solid content per 1 m ² .

(Preparation of coating solution for outermost back coating)
Each material shown in Table 4 was sufficiently stirred and mixed using a homogenizer, then mixed and filtered with the composition shown in Table 4, diluted with pure water and dispersed to prepare a coating solution for the outermost layer of the backing. .

In addition, the detail of each raw material is as having described in Table 4, and the numerical value in a table | surface represents the mass of the amount of solid content per m < ² >.

Example 1
(Preparation of printing plate 1)
A carriage type ink jet recording apparatus equipped with a piezo type ink jet nozzle was loaded with the prepared ink jet ink 1 and supplied onto the printing plate material 1 in an image-like manner to form an image. % Image with halftone dots). The piezo head was driven to discharge at a resolution of 1400 dpi (dpi represents the number of dots per 2.54 cm), and ink was continuously discharged.

The inkjet ink 1 landed on the printing plate material 1 was cured by a lamp unit to obtain the printing plate 1. As the lamp unit, a high-pressure mercury lamp VZero085 (manufactured by INTEGRATION TECHNOLOGY, peak wavelength: 254 nm, maximum illuminance: 400 mW / cm ² ) was used.

(Preparation of printing plate 2)
On the printing plate 1, the same image as that in the production of the printing plate 1 was formed so as to overlap the image on the printing plate 1. That is, the inkjet ink 1 was again supplied onto the cured image of the printing plate 1 and the ink was cured.

(Preparation of printing plate 3)
On the printing plate 2, the same image as that in the production of the printing plate 1 was formed so as to overlap the image on the printing plate 2. That is, the inkjet ink 1 was again supplied onto the cured image of the printing plate 2 and the ink was cured.

(Preparation of printing plate 4)
In the production of the printing plate 1, a printing plate 4 was produced in the same manner as in the production of the printing plate 1, except that the image was formed by simply doubling the ink discharge amount once for the same image.

(Evaluation of printing durability)
Using printing plates 1, 2, 3, and 4 and using DAIYA1F-1 manufactured by Mitsubishi Heavy Industries as a printing machine, coated paper, dampening water (ASTROMARK 3 (manufactured by Nikken Chemical Laboratories) 2% by mass), Printing was performed using ink (TK High Unity MZ Red, manufactured by Toyo Ink Co., Ltd.).

  The number of prints printed until half of the 3% halftone dots were missing was measured and used as an indicator of printing durability. The larger the number of printed sheets, the higher the printing durability. The results are shown in Table 5.

  From Table 5, it can be seen that the printing plate produced by the printing plate production method of the present invention maintains the resolution and is excellent in printing durability.

  The ink jet recording apparatus prepared as described above is filled in the ink jet recording apparatus adjusted so that the amount of liquid droplets ejected at one time can be changed, and the ink jet ink 2 is image-formed on the printing plate material 2. The mixture was supplied and dried at 50 ° C. for 5 seconds.

  The amount of one-time discharge was adjusted so that it was discharged a plurality of times to achieve a constant resolution (the same dot area). Images having the same resolution were each produced by a method with different ejection amount and ejection number. Drying was performed after discharging a plurality of times.

  That is, an image formed by ejecting the same point of the image by one discharge and an image formed by ejecting the same point to the same point a plurality of times were prepared (printing plate materials 2-1 to 2-7).

  Table 6 shows the resolution, the single discharge amount, the number of discharges, and the total ink amount supplied to one point.

(Evaluation of printing durability)
Using the above printing press, the printing plate material imaged as described above was directly attached to the plate cylinder, and printing was performed using the same printing conditions and printing sequence as the PS plate. That is, development was performed on a printing machine to prepare a printing plate, and printing was subsequently performed. By observing the printed matter, the halftone dot shape was evaluated, and the number of printed sheets at the time when an image defect (a portion where ink was not applied) was observed at the center of the halftone dot was measured and used as an index of printing durability. The results are shown in Table 6.

  From Table 6, it can be seen that the printing plate produced by the production method of the present invention is excellent in printing durability.

Claims (9)

In a printing plate manufacturing method including a step of supplying an image-forming droplet on a printing plate material to form an image, the step of supplying the image-forming droplet in an image manner to form an image A method for preparing a printing plate, comprising a plurality of printing plates. The method for producing a printing plate according to claim 1, wherein the image forming droplets are actinic ray curable ink droplets. The method for producing a printing plate according to claim 1, wherein the printing plate material is a substrate having a hydrophilic surface. The method for preparing a printing plate according to claim 1 or 2, wherein the printing plate material is a printing plate material having an ink receiving layer on a substrate having a hydrophilic surface. The method for preparing a printing plate according to claim 1, wherein the printing plate material is a printing plate material having an image forming layer containing a lipophilic component on a substrate having a hydrophilic surface. 6. The printing plate preparation method according to claim 5, wherein the image forming droplets are actinic ray curable ink droplets or liquid droplets containing an adhesive component. The method for producing a printing plate according to any one of claims 1 to 6, wherein the droplets for image formation are droplets by an ink jet recording method. The printing plate material having an image is developed on a printing machine after the step of forming the image by supplying the image-forming droplets in an image-like manner to produce a printing plate. A method for preparing a printing plate. An ink jet recording apparatus used in the printing plate preparation method according to claim 7.