JP2006334875A - Lithographic printing plate, method and equipment for platemaking of lithographic printing plate, printing method using lithographic printing plate and printing machine using lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lithographic printing plate which uses an inkjet ink curable by a specific activation energy beam and excels in printing quality and plate wear resistance, a method and equipment for platemaking of the lithographic printing plate and a printing method and a printing machine using the lithographic printing plate. <P>SOLUTION: The inkjet ink curable by the activation energy beam is discharged in the shape of an image by an inkjet recording method onto a substrate having a hydrophilic surface and then cured by exposure to the activation energy beam so as to prepare the lithographic printing plate. This inkjet ink contains radical polymerizable compounds of SP values of 8.00-8.50 and 9.00-10.00, each making up 10-50 mass%. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lithographic printing plate using a specific active energy ray-curable inkjet ink, a lithographic printing plate making method, a lithographic printing plate making apparatus, a printing method using the lithographic printing plate, and a printing machine using the lithographic printing plate. .

  The present invention relates to a method for controlling image resolution on a printing substrate such as a printing plate. The present invention provides a method for forming a printing plate, wherein an oleophilic image portion is formed by depositing a fluid composition on a hydrophilic printing substrate by inkjet discharge. The invention also relates to such a printing plate for printing. The present invention can further improve the method for forming an image on a printing plate, and advantageously the inking properties and adhesion of the printing ink of the image formed on the printing substrate, thereby providing high image quality. And a printing method capable of printing with high printing durability.

  In recent years, with the digitization of print data, there has been a demand for CTP (computer top plate) that is inexpensive, easy to handle, and has the same printability as the PS plate. In particular, in recent years, there is an increasing expectation for a so-called processless plate that does not require a development process using a special agent and can be applied to a printing machine having a direct imaging function.

As an image forming method for a processless plate, an ink jet recording method has been proposed as one of the promising means, and a technique for forming an image by landing on a printing substrate using a photopolymerizable ink jet ink has been disclosed. (For example, refer to Patent Documents 1 to 6.) However, the printing plates formed by the methods disclosed in these publications are not satisfactory in terms of printing quality and printing durability, and improvements are desired.
Japanese Patent Laid-Open No. 5-204138 JP 2003-220699 A JP 2003-231374 A JP 2003-246818 A Special table 2003-520706 gazette Japanese Patent Laid-Open No. 2004-2616

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a lithographic printing plate excellent in printing quality and printing durability by using a specific active energy ray-curable inkjet ink, and the lithographic printing An object is to provide a plate making method, a plate making apparatus, a printing method, and a printing machine using a plate.

  The above object of the present invention can be achieved by the following constitution.

(Claim 1)
In a lithographic printing plate produced by ejecting an active energy ray-curable inkjet ink imagewise by an inkjet recording method onto a support having a hydrophilic surface and then curing by irradiation with active energy rays, the active energy rays The curable ink-jet ink is an active energy ray-curable ink-jet ink containing 10 to 50% by mass of a radical polymerizable compound having an SP value of 8.0 to 8.50 and an SP value of 9.00 to 10.00, respectively. A lithographic printing plate.

(Claim 2)
The radically polymerizable compound having an SP value of 8.00 to 8.50 is a polymerizable compound selected from acrylic acid esters and methacrylic acid esters having an alkyl group having 4 to 18 carbon atoms. The lithographic printing plate as described.

(Claim 3)
The radically polymerizable compound having an SP value of 9.01 to 10.00 is a polymerizable compound containing any one of two or more ethylene oxide groups or two or more propylene oxide groups. The planographic printing plate according to claim 1.

(Claim 4)
After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A lithographic printing plate characterized by irradiating an active energy ray to cure an active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface to produce a lithographic printing plate Plate making method.

(Claim 5)
After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A lithographic printing plate characterized by irradiating an active energy ray to cure an active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface to produce a lithographic printing plate Plate making equipment.

(Claim 6)
After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A dampening solution and a printing ink are supplied to a lithographic printing plate produced by irradiating an active energy ray to cure the active energy ray-curable inkjet ink formed like an image on a support having a hydrophilic surface. A printing method using a lithographic printing plate, wherein a series of operations for producing a printed matter is performed on a printing machine.

(Claim 7)
The active energy ray-curable inkjet ink used for producing the lithographic printing plate according to any one of claims 1 to 3 is ejected imagewise by an inkjet recording method and then on a support having a hydrophilic surface. Further, dampening water and printing ink are supplied to a lithographic printing plate produced by irradiating an active energy ray to cure the active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface. A printing machine using a planographic printing plate, wherein a series of operations for producing a printed matter is performed on the printing machine.

  According to the present invention, a lithographic printing plate excellent in printing quality and printing durability using a specific active energy ray-curable inkjet ink, and a plate making method, plate making apparatus, printing method and printing machine using the lithographic printing plate Can be provided.

  Hereinafter, although the best mode for carrying out the present invention will be described, the present invention is not limited to these.

  The active energy ray-curable inkjet ink according to the present invention is composed of at least an active energy ray polymerizable compound (hereinafter also simply referred to as a polymerizable compound). In addition, a coloring material can be added for the purpose of obtaining visible image quality.

  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. The dispersion medium is a solvent or a polymerizable compound, but the radiation curable ink according to the present invention is preferably solvent-free 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 lithographic printing plate of the present invention is prepared by discharging an active energy ray-curable inkjet ink imagewise by an inkjet recording method onto a support having a hydrophilic surface, and then curing by irradiation with an active energy ray. In the printing plate, the active energy ray-curable inkjet ink contains 10 to 50% by mass of radically polymerizable compounds having an SP value of 8.00 to 8.50 and an SP value of 9.00 to 10.00, respectively. It is a characteristic inkjet ink.

  The active energy ray-curable inkjet ink according to the present invention has an SP value of 8.00 to 8.50, preferably 8.20 to 8.45, and an SP value of 9.00 to 10.00, preferably 9.40. 10 to 50% by mass, preferably 20 to 40% by mass, of the radically polymerizable compound of ˜10.00.

  If the SP value is less than 8.00 for each numerical limitation, there is a concern that the print quality and printing durability deteriorate. On the other hand, if it exceeds 8.50, there is a concern that the printing quality and printing durability deteriorate. Moreover, if it is less than 9.00, there is a concern that the printing quality and printing durability deteriorate. On the other hand, if it exceeds 10.00, there is a concern that the printing quality and printing durability deteriorate.

  Further, if the content is less than 10% by mass for each numerical limitation, there is a concern that the printing quality and printing durability deteriorate. On the other hand, if it exceeds 50 mass%, there is a concern that the printing quality and printing durability deteriorate.

  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 methacryl derivatives such as trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, and other derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, triallyl trimellitate, and the like. In the book, Shinzo Yamashita, “Cross-linking agent handbook” (Taisei, 1981); Dobook (raw material edition) "(1985, Polymer publication society); Radtech study group 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.

  Of these radically polymerizable compounds, the radically polymerizable compound having an SP value of 9.01 to 10.00 of the present invention is preferably a polymerizable compound containing any one of two or more ethylene oxide groups and propylene oxide groups. Used. Specific compounds include, for example, EO-modified bisphenol A diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, EO-modified trimethylolpropane triacrylate, PO-modified trimethylolpropane triacrylate, neopentyl glycol PO-modified diacrylate, and the like. Can be mentioned.

  In the present invention, the compound is preferably used in an amount of 10 to 50% by mass in the ink.

  Of the radical polymerizable compounds, acrylic acid esters and methacrylic acid esters having an alkyl group having 4 to 18 carbon atoms are preferably used as the radical polymerizable compound having an SP value of 8.00 to 8.50 of the present invention. Specific compounds include, for example, n-butyl acrylate, iso-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, tridecyl acrylate, stearyl acrylate, cyclohexyl acrylate, and the like. Examples thereof include n-butyl acid, iso-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, stearyl methacrylate, and cyclohexyl methacrylate.

  In the present invention, the compound is preferably used in an amount of 10 to 50% by mass in the ink.

  The SP value employed in the present invention is calculated by Toshinao Okitsu, Adhesion, p. 343, 40, Vol. 8, Adhesion Romance and Story (34) Development of Solubility Theory (1996).

  When an electron beam, X-ray, or the like is used as irradiation light, an initiator is not necessary, but when UV light, visible light, or infrared light is used as a radiation source, a radical polymerization initiator or cation corresponding to each wavelength is used. A 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 thiooxanthone, benzophenone, quinone, and phosphine oxide.

  Moreover, in order to improve preservability, 200-20000 ppm of polymerization inhibitors can be added. The ink of the present invention is preferably heated and reduced in viscosity in the range of 40 to 80 ° C. and ejected. Therefore, it is preferable to add a polymerization inhibitor in order to prevent head clogging due to thermal polymerization.

  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.

  In order to improve the adhesion with the hydrophilic layer, 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%.

  The active energy ray-curable inkjet ink of the present invention preferably has a viscosity at 50 ° C. of 5 to 30 mPa · s. The viscosity at the time of flight is preferably 40 mPa · s or less, and more preferably 30 mPa · s or less.

  The temperature of the inkjet head when discharging ink droplets is preferably 40 ° C. or higher, and more preferably 60 to 180 ° C. If it is less than 40 ° C. or exceeds 180 ° C., injection becomes difficult. Further, the temperature of the recording medium on which ink droplets are ejected to form an image is preferably 15 to 40 ° C., and the deterioration of bleeding is large at 40 ° C. or higher.

  Curing of the active energy ray-curable inkjet ink by irradiation with active energy 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.

  Examples of the support having a hydrophilic surface of the present invention include Japanese Patent No. 2938397, Japanese Patent No. 2938397, Japanese Patent No. 3019366, Japanese Patent Application Laid-Open No. 9-99662, Japanese Patent Application Laid-Open No. 2002-331768, Japanese Patent Application Laid-Open No. 2003-231374. A hydrophilic layer or an aluminum grain support disclosed in JP-T-2003-520706 can be used.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.

Example 1
(Preparation of support 1 having a hydrophilic surface)
An aluminum plate (material 1050, tempered H16) having a thickness of 0.24 mm was immersed in a 5 mass% sodium hydroxide aqueous solution at 65 ° C., degreased for 1 minute, and then washed with water. The degreased aluminum plate was neutralized by immersion in a 10% by mass hydrochloric acid aqueous solution at 25 ° C. for 1 minute, and then washed with water. Next, this aluminum plate was subjected to electrolytic surface roughening with an alternating current for 60 seconds under conditions of 25 ° C. and a current density of 100 A / dm ^{2 in} a 0.3% by mass nitric acid aqueous solution, and then 5 ° C. at 60 ° C. A desmut treatment for 10 seconds was carried out in a mass% aqueous sodium hydroxide solution. The surface-roughened aluminum plate subjected to desmut treatment was anodized for 1 minute in a 15% by mass sulfuric acid solution at 25 ° C., a current density of 10 A / dm ² , and a voltage of 15 V, thereby producing a support 1. .

(Preparation of support 2 having a hydrophilic surface)
After sufficiently stirring and mixing the following hydrophilic layer coating solution using a homogenizer, the thickness becomes 3 μm on a 188 μm thick polyethylene terephthalate film (HS74, manufactured by Teijin Limited) provided with an undercoat layer for aqueous coating. The support 2 was prepared by coating and drying.

Hydrophilic layer coating solution Colloidal silica (alkaline):
Snowtex-S (manufactured by Nissan Chemical Co., Ltd., solid content 30% by mass) 18.87 parts by mass Necklace-shaped colloidal silica (alkaline):
Snowtex-PSM (Nissan Chemical Co., Ltd., solid content 20% by mass) 44.70 parts by mass Layered mineral particles Montmorillonite: Mineral colloid MO (manufactured by Southern Clay Products, average particle size of about 0.1 μm) is vigorously stirred with a homogenizer. 5 wt% water swelling gel
8.0 parts by mass A 4% by mass aqueous solution of sodium carboxymethylcellulose (a reagent manufactured by Kanto Chemical Co., Inc.)
5.0 parts by mass 10% by mass aqueous solution of trisodium phosphate dodecahydrate (reagent manufactured by Kanto Chemical Co., Inc.)
1.0 part by mass Porous metal oxide particles SILTON AMT08 (manufactured by Mizusawa Chemical Co., Ltd., porous aluminosilicate particles, average particle size 0.6 μm)
2.4 parts by mass Porous metal oxide particles Shilton JC-20 (manufactured by Mizusawa Chemical Co., Ltd., porous aluminosilicate particles, average particle size 2 μm)
2.0 parts by mass pure water 17.03 parts by mass (production of active energy ray-curable inkjet ink)
After mixing and stirring the ink compositions shown in Tables 1 and 2, the obtained liquid was filtered with a filter to obtain inks 1 to 8.

(Preparation of printing plate)
The obtained ink is printed on the support having the hydrophilic surface by an ink jet recording apparatus having a piezo ink head (heated to 60 ° C., ink sample No. 7 is not discharged at 60 ° C. and heated to 100 ° C.). After that, the substrate was cured by an ultraviolet irradiation device (one metal halide lamp: output 120 W) under the condition of the substrate conveyance speed of 10 m / min.

(Preparation of printed matter)
The lithographic printing plate produced above is attached to a printing machine (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), and coated paper, dampening water, ink (Toyo King High Echo M Red manufactured by Toyo Ink Co., Ltd.) is used. Printing was done.

  The obtained printed matter was evaluated according to the following evaluation criteria. Table 3 shows the evaluation results.

(Print quality)
The image quality was visually evaluated according to the following criteria.

◎ ・ ・ ・ Bleeding, chipping, and printability are good ○ ・ ・ ・ Slight bleeding and chipping occur △ ・ ・ ・ Bleeding and chipping is possible, but identification is possible × ・ ・ ・ Bleeding, Chipping is impossible to identify (printing durability)
The production of the printed matter was performed in the same manner except that the printing paper was changed to high-quality paper, and the number of printed sheets at the time when problems such as missing images and imperfect printing ink imprinting occurred in the printing quality was defined as the printing durability. The larger the value, the better.

Note) The amount added in the table is% by mass.
Note) The viscosity unit in the table is mPa · s, the measurement temperature is 25 ° C., Shear Rate = 1000 (1 / s), Rheometer MCR300 (manufactured by Physica)

  Note) For example, planographic printing plate no. 1-2 is an ink sample No. 1-2. 1 and support no. 2 (that is, a support plate No. 2 having a hydrophilic surface) means a lithographic printing plate sample.

  From Table 1, Table 2, and Table 3, the activity which contains 10-50 mass% of radically polymerizable compounds with SP values of 8.00 to 8.50 and SP values of 9.00 to 10.00, respectively, as radically polymerizable compounds. It can be seen that the lithographic printing plate of the present invention using the energy beam curable inkjet ink has good printing quality and printing durability without bleeding and chipping.

Example 2
Next, the printing press of the present invention will be described.

  Hereinafter, the printer of the present invention will be described with reference to the drawings as appropriate. Note that the recording apparatus of the drawing is merely one aspect of the printing machine of the present invention, and the printing machine of the present invention is not limited to this drawing.

  FIG. 1 is a schematic cross-sectional view showing the configuration of the main part of the printing press of the present invention.

  In FIG. 1, the printing paper conveyed from the printing paper former winding roll 1 is transferred with printing ink from the printing plate at the place where the blanket cylinder and the impression cylinder are in contact, and the produced printed matter is taken up by the winding roller 2.

  An active energy ray-curable inkjet ink is ejected from the inkjet recording head 3 onto a support 5 having a hydrophilic surface wound around the plate cylinder 4, and the ink image on the support 5 having a hydrophilic surface is an actinic ray. Irradiated with actinic rays by the irradiation device 6, the ink image is cured and fixed on the support 5 having a hydrophilic surface, and a printing plate is produced.

  Next, dampening water is supplied onto the printing plate from a dampening water supply device, and dampening water is deposited on the hydrophilic surface of the exposed printing plate. Next, the printing ink is supplied from the printing ink supply device onto the printing plate and adheres onto the cured ink image.

  The printing ink adhering to the cured ink image is transferred to the surface of the blanket cylinder 10 and then transferred onto the transported printing paper at a location where the blanket cylinder and the impression cylinder are in contact with each other.

  In the figure, the device of only the part surrounded by a red frame is a plate making device, which is used for producing a printing plate.

It is a schematic sectional drawing which shows an example of a structure of the principal part of the printing press of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printing paper original winding 2 Printed material winding 3 Inkjet recording head 4 Plate cylinder 5 Printing plate 6 Actinic ray irradiation apparatus 7 Pressure cylinder 8 Dampening water supply apparatus 9 Printing ink supply apparatus 10 Blanket cylinder

Claims (7)

In a lithographic printing plate produced by ejecting an active energy ray-curable inkjet ink imagewise by an inkjet recording method onto a support having a hydrophilic surface and then curing by irradiation with active energy rays, the active energy rays The curable ink-jet ink is an active energy ray-curable ink-jet ink containing 10 to 50% by mass of a radical polymerizable compound having an SP value of 8.0 to 8.50 and an SP value of 9.00 to 10.00, respectively. A lithographic printing plate. The radically polymerizable compound having an SP value of 8.00 to 8.50 is a polymerizable compound selected from acrylic acid esters and methacrylic acid esters having an alkyl group having 4 to 18 carbon atoms. The lithographic printing plate as described. The radically polymerizable compound having an SP value of 9.01 to 10.00 is a polymerizable compound containing any one of two or more ethylene oxide groups or two or more propylene oxide groups. The planographic printing plate according to claim 1. After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A lithographic printing plate characterized by irradiating an active energy ray to cure an active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface to produce a lithographic printing plate Plate making method. After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A lithographic printing plate characterized by irradiating an active energy ray to cure an active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface to produce a lithographic printing plate Plate making equipment. After ejecting the active energy ray-curable inkjet ink used for preparing the lithographic printing plate according to any one of claims 1 to 3 imagewise by an inkjet recording method onto a support having a hydrophilic surface. A dampening solution and a printing ink are supplied to a lithographic printing plate produced by irradiating an active energy ray to cure the active energy ray-curable inkjet ink formed like an image on a support having a hydrophilic surface. A printing method using a lithographic printing plate, wherein a series of operations for producing a printed matter is performed on a printing machine. The active energy ray-curable inkjet ink used for producing the lithographic printing plate according to any one of claims 1 to 3 is ejected imagewise by an inkjet recording method and then on a support having a hydrophilic surface. Further, dampening water and printing ink are supplied to a lithographic printing plate produced by irradiating an active energy ray to cure the active energy ray-curable inkjet ink formed in an image-like manner on a support having a hydrophilic surface. A printing machine using a planographic printing plate, wherein a series of operations for producing a printed matter is performed on the printing machine.

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