JP4855028B2 - Ink composition for inkjet recording, inkjet recording method, method for producing lithographic printing plate, and lithographic printing plate - Google Patents

Description

The present invention is an ink jet recording Lee ink composition, inkjet recording method, further, a process for producing a lithographic printing plate and a lithographic printing plate obtained using the ink. For more information, obtained for irradiation with actinic radiation, it cures with high sensitivity, an ink jet recording Lee ink composition having sufficient flexibility cured product even after curing ink jet recording method, and, by using the ink The present invention relates to a lithographic printing plate and a method for producing a lithographic printing plate.

As an image recording method for forming an image on a recording medium such as paper based on an image data signal, there are an electrophotographic method, a sublimation type and a melt type thermal transfer method, an ink jet method and the like. The electrophotographic system requires a process of forming an electrostatic latent image on a photosensitive drum by charging and exposure, and there is a problem that the system becomes complicated and consequently the manufacturing cost becomes high. In addition, although the thermal transfer system is inexpensive, there are problems such as high running costs and waste materials due to the use of ink ribbons.
On the other hand, the ink jet method is an inexpensive device and ejects ink only to a required image portion to form an image directly on a recording medium. Therefore, the ink can be used efficiently and the running cost is low. Furthermore, there is little noise and it is excellent as an image recording method.

  Ink compositions that can be cured by irradiation with actinic radiation such as ultraviolet rays (radiation curable ink compositions), such as ink compositions for ink jet recording, can be cured with high sensitivity and form high-quality images. It has been demanded. By achieving high sensitivity, high curability is imparted by irradiation with actinic radiation, so that sufficient curing is achieved in addition to reducing power consumption and extending life by reducing the load on the actinic radiation generator. As a result, there are various advantages such as suppression of volatilization of uncured low molecular weight substances and reduction in the strength of the formed image. Further, the improvement in the image strength by increasing the sensitivity results in high printing durability in the image area when this ink composition is used for forming the image area of a lithographic printing plate.

  The curable inkjet method using ultraviolet light has been attracting attention in recent years because it has a relatively low odor and can record on a recording medium having no quick drying and no ink absorption. In particular, benzyl, benzoin, benzoin ethyl ether, Michler ketone, anthraquinone, acridine, phenazine, benzophenone, 2-ethylanthraquinone, and the like have been generally used as photopolymerization initiators (for example, see Non-Patent Document 1). However, when these photopolymerization initiators are used, it takes a long time for image exposure in image formation because the photopolymerizable composition has low curing sensitivity. Therefore, in the case of a fine image, if there is a slight vibration in the operation, an image with good image quality cannot be reproduced, and the amount of energy emitted from the light source for exposure must be increased. It was necessary to consider the emission of heat.

  Even for a support that is usually difficult to directly record with an ink jet recording method, it is possible to record an image with no bleeding, high sensitivity, high adhesion to a recording medium, and skin irritation and sensitization. For the purpose of providing an ink composition with low safety and high safety, a composition containing a polymerizable compound consisting of a specific acrylate compound group has been proposed (for example, see Patent Document 1). However, the polyfunctional acrylate used for the purpose of improving the sensitivity has a three-dimensional structure in which a polymer obtained by curing is highly crosslinked, so that the flexibility and impact resistance after ink curing are reduced, and on the recording medium Cracks and peeling easily occur, and there is a problem in the durability of the formed image.

Conventionally, in the production of a lithographic printing plate, a so-called PS plate having a configuration in which an oleophilic photosensitive resin layer is provided on a hydrophilic support is used, and the photosensitive resin layer is exposed imagewise. Thus, an image is formed by improving or decreasing the solubility of the exposed portion in an alkaline developer, and the non-image portion is dissolved and removed. However, in recent years, digitization techniques for electronically processing, storing, and outputting image information using a computer have become widespread, and a new image output method corresponding to the technique has been demanded. In particular, a method capable of producing a printing plate without undergoing treatment with a developing solution has been studied, and a method of directly producing a lithographic printing plate using an ink composition for inkjet recording has been studied (for example, see Patent Document 2). This is preferably a printing plate having a desired image (preferably a hydrophobic image) by ejecting ink onto the surface of a hydrophilic support in an image-like manner by an inkjet method or the like and irradiating it with actinic radiation to cure it. Is what you get. In order to form an image part of a lithographic printing plate, ink droplets ejected on a support are cured quickly without causing bleeding, and the strength of the cured image part and adhesion to the support are excellent. In addition, it is desired that the image portion follows the flexure of the support when the lithographic printing plate is mounted on a printing machine so that damage such as cracks does not occur. Ink compositions suitable for such applications The current situation is that something is desired.
JP 2003-192943 A JP 54-117203 A Bruce M. Monroe (Bruce M. Monroe et al., Chemical Reviews, Vol. 93, (1993), p. 435-448.

An object of the present invention is an ink composition that can be cured with high sensitivity to irradiation with actinic radiation, can form a high-quality image, and an image obtained by curing the ink has sufficient flexibility. An object of the present invention is to provide an ink jet recording method using an ink composition.
Another object of the present invention is to provide a lithographic printing plate obtained using an ink composition that can be cured with high sensitivity by irradiation with ultraviolet rays, and a method for producing the lithographic printing plate.

As a result of intensive studies, the inventors have improved the flexibility after ink curing while maintaining high sensitivity by using a specific polymerizable compound in the ink composition, The inventors have found that an ink composition with improved particle shape retention and adhesion to a recording medium can be obtained, and the present invention has been completed.
That is, at least one ink composition of the polymerization initiator, in a molecular having a carboxyl group and one (meth) acryloyl group-containing (meth) selected from the group consisting of esters or amides of acrylic acid of the present invention And a compound comprising:
Although the operation of the present invention is not clear, it is estimated as follows.
In the present invention, as the polymerizable compound, a monofunctional polymerizable monomer (meth) acrylic acid ester or (meth) acrylic acid amide introduced with a carboxy group that is a strong hydrogen bonding unit is used. This carboxy group forms a hydrogen bonding interaction as shown below in a plurality of adjacent monomers, and functions as if it were a bifunctional monomer. For this reason, it is considered that a decrease in the curing rate, which is a problem in the monofunctional monomer, is suppressed, and highly sensitive curing by radiation irradiation is possible. In addition, since the bond due to such interaction is not as strong as the bond in the usual polyfunctional monomer linked by the covalent bond, the film formed after the curing reaction is more than the case where the polyfunctional monomer is used. Will also be excellent in flexibility.

  When forming a colored image with this ink composition, a colorant may be further contained. The ink composition of the present invention is suitable for inkjet recording because it is cured with high sensitivity by irradiation and the flexibility of the film formed on the ink surface is improved.

Also, Lee inkjet recording method of the present invention, onto a recording medium (a), a step of discharging the ink composition of the present invention, and are irradiated with active radiation to the ink composition discharged (b) And a step of curing the ink composition.
Method for producing a flat plate printing plate of the present invention, on the (a) hydrophilic support, a step of discharging the ink composition, and are irradiated with active radiation to the ink composition discharged (b), Forming a hydrophobic image formed by curing the ink composition on the hydrophilic support by curing the ink composition.
Flat plate printing plate of the present invention is characterized in that it is manufactured by the method for producing a lithographic printing plate of the present invention.

As described above, according to the present invention, it can be cured with high sensitivity to irradiation with actinic radiation, can form a high-quality image, and the image obtained by curing the ink has sufficient flexibility. An ink composition and an ink jet recording method using the ink composition can be provided.
Moreover, the planographic printing plate obtained using the ink composition which can be hardened | cured with high sensitivity by ultraviolet irradiation, and the manufacturing method of a planographic printing plate can be provided.

<Ink composition>
Inkjet recording ink composition of the present invention comprises (A) a polymerization initiator and, (B) component child having a carboxyl group and one (meth) acryloyl groups in the (meth) acrylic acid ester or amide And at least one compound selected from the group.
Hereinafter, the ink composition of the present invention will be described in detail.

Hereinafter, components essential to the ink composition of the present invention will be sequentially described.
[(B) component daughterscope the carboxy group and one (meth) having an acryloyl group (meth) acrylic acid ester or amide]
The ink composition of the present invention, in the molecular and a carboxy group and one (meth) acryloyl group-containing (meth) acrylic acid ester or amide [hereinafter, appropriately referred to as component (B) or specific polymerizable compound And at least one compound selected from the group consisting of:
The specific polymerizable compound may be used as long as (meth) acrylic acid ester or amide having one (meth) acryloyl groups and one or more carboxyl groups in the molecular. The number of carboxy groups present in the molecule is preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1.
As the specific polymerizable compound, a compound represented by the following general formula (I) is preferable.

  In the formula, R represents a hydrogen atom or a methyl group, and is preferably a hydrogen atom from the viewpoint of reactivity and flexibility of a polymer produced by a polymerization reaction. X represents an oxygen atom or NR ′, and is preferably an oxygen atom because it improves the mobility around the polymerizable site. R 'represents a hydrogen atom or an alkyl group, preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and particularly preferably a hydrogen atom. Z represents a divalent organic group, and preferred divalent organic groups include the following.

Compound represented by the general formula (I) from the viewpoint of handling properties such as odor can be more preferably used in the present invention.
Specific examples that can be suitably used in the specific polymerizable compound of the present invention are shown below.

  The specific polymerizable compound is preferably used alone or in combination of two or more. The content of the specific polymerizable compound is preferably in the range of 5 to 45% by mass, and preferably 10 to 35% by mass with respect to the total amount of the ink composition, from the viewpoint of the balance between the curing speed and flexibility and the inkjet suitability of the ink composition. The range of is more preferable.

(A) Polymerization initiator The ink composition of the present invention contains a polymerization initiator. As the polymerization initiator, a known polymerization initiator can be used. In the present invention, it is preferable to use a radical polymerization initiator.
The polymerization initiator used in the ink composition of the present invention is a compound that absorbs external energy and generates a polymerization initiating species. External energy used for initiating polymerization is roughly divided into heat and radiation, and a thermal polymerization initiator and a photopolymerization initiator are used, respectively. Examples of radiation include γ rays, β rays, electron beams, ultraviolet rays, visible rays, and infrared rays.
When the polymerizable compound is cured by irradiating the electron beam, it may be cured without using a polymerization initiator.
Known compounds can be used as the thermal polymerization initiator and the photopolymerization initiator.

(A-1) Radical polymerization initiator Preferred radical polymerization initiators that can be used in the present invention include (a) aromatic ketones, (b) acylphosphine compounds, (c) aromatic onium salt compounds, and (d) organic. Peroxide, (e) thio compound, (f) hexaarylbiimidazole compound, (g) ketoxime ester compound, (h) borate compound, (i) azinium compound, (j) metallocene compound, (k) active ester Compounds, (l) compounds having a carbon halogen bond, and (m) alkylamine compounds.
The radical polymerization initiator of the present invention may be used alone or in combination.

(A-2) Cationic polymerization initiator In the present invention, as described later, when a cationic polymerizable compound is used in combination, it is preferable to use a cationic polymerization initiator in combination.
As a preferable cationic polymerization initiator (photoacid generator) that can be used in the present invention, for example, a chemical amplification type photoresist or a compound used for photocationic polymerization is used (Organic Electronics Materials Research Group, “For Imaging”). “Organic materials”, Bunshin Publishing (1993), pages 187-192). Examples of the cationic polymerization initiator suitable for the present invention are listed below.

First, B (C ₆ F ₅ ) ₄ ⁻ , PF ₆ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , CF ₃ SO ₃ ⁻ salt of aromatic onium compounds such as diazonium, ammonium, iodonium, sulfonium, phosphonium, etc. be able to. Secondly, sulfonated products that generate sulfonic acid can be mentioned. Thirdly, a halide that generates hydrogen halide can also be used. Fourthly, an iron allene complex can be mentioned.

  The polymerization initiator in the present invention is suitably used alone or in combination of two or more. These (A) polymerization initiators are preferably used with respect to the total amount of the polymerizable compound when the component (B) or (C) another polymerizable compound as an optional component is used in combination. It is suitably contained in the range of 0.01 to 35% by mass, more preferably 0.1 to 30% by mass, and still more preferably 0.5 to 30% by mass. Moreover, in this invention, (A) polymerization initiator is 200: 1 to 1 by mass ratio of a polymerization initiator: sensitizing dye with respect to (E) sensitizing dye which can be used as needed later. : 200, preferably 50: 1 to 1:50, more preferably 20: 1 to 1: 5.

In the ink composition of the present invention, in addition to the essential components described above, other components can be used in combination for the purpose of improving physical properties as long as the effects of the present invention are not impaired. These optional components are described below.
(C) Other polymerizable compound The ink composition of the present invention preferably contains another (C) another polymerizable compound in addition to the specific polymerizable compound as the component (B). Examples of other polymerizable compounds that can be used in combination with the present invention include radically polymerizable compounds and cationically polymerizable compounds. (C) Other polymerizable compounds may be appropriately selected and used in relation to the objective properties or the relationship with (A) the polymerization initiator.

(C-1) Radical polymerizable compound The radical polymerizable compound is a compound having an ethylenically unsaturated bond capable of radical polymerization, and having at least one ethylenically unsaturated bond capable of radical polymerization in the molecule. Any type may be used, including those having chemical forms such as monomers, oligomers, and polymers. 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. It is preferable to use two or more kinds in combination for controlling performance such as reactivity and physical properties.

Examples of the polymerizable compound 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 salts thereof, Examples thereof include radically polymerizable compounds such as anhydrides having a saturated group, acrylonitrile, styrene, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.
Specifically, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, bis (4-acryloxypolyethoxyphenyl) propane, neopentyl glycol Diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol Tetraacrylate, dipentaery Acrylic acid derivatives such as lithol tetraacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, N-methylol acrylamide, diacetone acrylamide, epoxy acrylate, methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate , Lauryl methacrylate, allyl methacrylate, glycidyl methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylol Methacryl derivatives such as tan trimethacrylate, trimethylolpropane trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, and other derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, triallyl trimellitate More specifically, Shinzo Yamashita, “Cross-linking agent handbook”, (1981 Taiseisha); Kato Kiyomi, “UV / EB curing handbook (raw material)” (1985, Polymer publication) ); Rad-Tech Study Group, “Application and Market of UV / EB Curing Technology”, p. 79, (1989, CMC); Eiichiro Takiyama, “Polyester Resin Handbook”, (1988, Nikkan Kogyo Shimbun) Commercially available products described in the above, or radically polymerizable or crosslinkable monomers known in the industry, Ligomers and polymers can be used.

  Examples of the radical polymerizable compound are described in JP-A-7-159983, JP-B-7-31399, JP-A-8-224982, JP-A-10-863, JP-A-9-134011 and the like. There are known photocurable polymerizable compound materials used for photopolymerizable compositions, and as cationic polymerizable compounds, for example, polymerizable compounds applicable to cationic polymerization type photocurable resins are known. Recently, as a polymerizable compound applied to a photo-cationic polymerization type photocurable resin sensitized to a visible light wavelength region of 400 nm or more, for example, JP-A-6-43633 and JP-A-8-324137. Published in each publication.

(C-2) Cationic polymerizable compound A cationically polymerizable compound may be used in combination with the ink composition of the present invention, if necessary.
The cationically polymerizable compound used in the present invention is not particularly limited as long as it is a compound that initiates a polymerization reaction with an acid generated from a photoacid generator and cures, and various known cationic polymerizations known as photocationically polymerizable monomers. Sex monomers can be used. Examples of the cationic polymerizable monomer include JP-A-6-9714, JP-A-2001-31892, JP-A-2001-40068, JP-A-2001-55507, JP-A-2001-310938, JP-A-2001-310937, and 2001-2001. Examples thereof include epoxy compounds, vinyl ether compounds, oxetane compounds and the like described in each publication such as No. 220526.

  In the ink composition of the present invention, these cationic polymerizable compounds may be used alone or in combination of two or more, but from the viewpoint of effectively suppressing shrinkage during ink curing. Is preferably a combination of at least one compound selected from oxetane compounds and epoxy compounds and a vinyl ether compound.

(C-3) Other preferred polymerizable compounds Other polymerizable compounds used in the present invention include (meth) acrylic monomers or prepolymers, epoxy monomers or prepolymers, urethane monomers or prepolymers ( A (meth) acrylic acid ester (hereinafter referred to as “acrylate compound” where appropriate) is preferred. More preferably, they are the following compounds.

  2-ethylhexyl-diglycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxybutyl acrylate, hydroxypivalate neopentyl glycol diacrylate, 2-acryloyloxyethyl phthalate, methoxy-polyethylene glycol acrylate, tetramethylol Methane triacrylate, 2-acryloyloxyethyl-2-hydroxyethylphthalic acid, dimethylol tricyclodecane diacrylate, ethoxylated phenyl acrylate, 2-acryloyloxyethyl succinic acid, nonylphenol EO adduct acrylate, modified glycerin triacrylate Bisphenol A diglycidyl ether acrylic acid adduct, modified bisphenol A diacrylate, phenoxy-polyethylene Glycol acrylate, 2-acryloyloxyethyl hexahydrophthalic acid, PO adduct diacrylate of bisphenol A, EO adduct diacrylate of bisphenol A, dipentaerythritol hexaacrylate, pentaerythritol triacrylate tolylene diisocyanate urethane prepolymer, Lactone modified flexible acrylate, butoxyethyl acrylate, propylene glycol diglycidyl ether acrylic acid adduct, pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, 2-hydroxyethyl acrylate, methoxydipropylene glycol acrylate, ditrimethylolpropane tetra Acrylate, pentaerythritol triacrylate hexamethylene di Socia isocyanate urethane prepolymer, stearyl acrylate, isoamyl acrylate, isomyristyl acrylate, isostearyl acrylate, etc. lactone-modified acrylate.

  These acrylate compounds have less skin irritation and sensitization (ease of rashes) than conventional polymerizable compounds used in UV curable inks, and can relatively lower the viscosity, providing stable ink ejection. The polymerization sensitivity and the adhesion to the recording medium are also good.

  (C) Monomers listed as other polymerizable compounds have low sensitization even at low molecular weight, and have high reactivity, low viscosity, and excellent adhesion to a recording medium. .

In order to further improve sensitivity, bleeding, and adhesion to the recording medium, it is preferable to use monoacrylate in combination with a polyfunctional acrylate monomer or polyfunctional acrylate oligomer having a molecular weight of 400 or more, preferably 500 or more. In particular, in an ink composition used for recording on a flexible recording medium such as a PET film or a PP film, a combination of a monoacrylate selected from the above compound group and a polyfunctional acrylate monomer or polyfunctional acrylate oligomer is This is preferable because the film strength can be increased while the film is flexible to improve adhesion.
In addition, the aspect in which at least three polymerizable compounds of monofunctional, bifunctional, and trifunctional or higher polyfunctional monomers are used in combination further improves sensitivity, bleeding, and adhesion to the recording medium while maintaining safety. From the viewpoint that it can be improved, it is preferable.

As monoacrylates, stearyl acrylate, isoamyl acrylate, isomystil acrylate, and isostearyl acrylate have high sensitivity and low shrinkage to prevent curling, and are preferable in terms of prevention of bleeding, odor of printed matter, and cost reduction of irradiation apparatus. .
As the oligomer that can be used in combination with the monoacrylate, an epoxy acrylate oligomer and a urethane acrylate oligomer are particularly preferable.
In addition, methacrylate has better skin irritation than acrylate.
Among the above compounds, when alkoxy acrylate is used in an amount of 70% by mass or less and the balance is acrylate, it is preferable because it has good sensitivity, bleeding characteristics, and odor characteristics.

  In the present invention, when the acrylate compound is used as (C) the other polymerizable compound, the acrylate compound is 10% by mass or more based on the total mass of the other polymerizable compound (that is, the total amount of the component (C)). Preferably, it is 15% by mass or more, and more preferably 20% by mass or more. Moreover, (C) all the other polymerizable compounds used together can also be made into the said acrylate compound.

<Addition amount of polymerizable compound>
In the present invention, the amount of the polymerizable compound containing the component (B), that is, the total content of the component (B) and the other polymerizable compound (C) that can be used in combination with the component is determined by the ink composition of the present invention. It is 5-97 mass% with respect to the mass of the whole thing, More preferably, it is 30-95 mass%.

  In the ink composition of the present invention, the component (B) is based on the total content of polymerizable compounds contained in the ink composition (that is, the total content of the components (B) and (C)). The content is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, and particularly preferably 30% by mass or more. Moreover, all of the (C) other polymerizable compound used together with (B) component can also be made into said acrylate compound.

  As for the selection of (A) the polymerization initiator and the polymerizable compound, as a means for preventing a decrease in sensitivity due to the light-shielding effect of the colorant used in the ink composition, a combination of a cationic polymerizable compound and a cationic polymerization initiator, In addition to a combination of a radical polymerizable compound and a radical polymerization initiator, a radical / cation hybrid curable ink may be used in combination of these polymerizable compound and polymerization initiator.

(D) Colorant When the ink composition of the present invention is used for forming an image portion of a lithographic printing plate, it is not particularly necessary to form a colored image, but in order to improve the visibility of the formed image portion, or When it is going to form a colored image using an ink composition, (D) a coloring agent can be contained.

  The colorant that can be used in the present invention is not particularly limited, but (D-1) pigments and (D-2) oil-soluble dyes that are excellent in weather resistance and rich in color reproducibility are preferable and are soluble. Any known colorant such as a dye can be selected and used. The colorant that can be suitably used in the ink composition of the present invention or the ink composition for inkjet recording functions as a polymerization inhibitor in a polymerization reaction that is a curing reaction from the viewpoint of not reducing the sensitivity of the curing reaction by actinic radiation. It is preferred to select compounds that do not.

(D-1) Pigment The pigment that can be used in the present invention is not particularly limited. For example, organic or inorganic pigments having the following numbers described in the color index can be used.
Examples of red or magenta pigments include Pigment Red 3, 5, 19, 22, 31, 38, 43, 48: 1, 48: 2, 48: 3, 48: 4, 48: 5, 49: 1, and 53: 1. 57: 1, 57: 2, 58: 4, 63: 1, 81, 81: 1, 81: 2, 81: 3, 81: 4, 88, 104, 108, 112, 122, 123, 144, 146 149, 166, 168, 169, 170, 177, 178, 179, 184, 185, 208, 216, 226, 257, Pigment Violet 3, 19, 23, 29, 30, 37, 50, 88, Pigment Orange 13 16, 20, 36,
As the blue or cyan pigment, Pigment Blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17-1, 22, 27, 28, 29, 36, 60 Pigment Green 7, 26, 36, 50,
As the yellow pigment, Pigment Yellow 1, 3, 12, 13, 14, 17, 34, 35, 37, 55, 74, 81, 83, 93, 94, 95, 97, 108, 109, 110, 137, 138 139, 153, 154, 155, 157, 166, 167, 168, 180, 185, 193,
As the black pigment, Pigment Black 7, 28, 26,
As a white pigment, Pigment White 6, 18, 21
Etc. can be used according to the purpose.

(D-2) Oil-soluble dye The oil-soluble dye that can be used in the present invention is described below.
The oil-soluble dye that can be used in the present invention means a dye that is substantially insoluble in water. Specifically, the solubility in water at 25 ° C. (the mass of the dye that can be dissolved in 100 g of water) is 1 g or less, preferably 0.5 g or less, more preferably 0.1 g or less. Therefore, the oil-soluble dye means a so-called water-insoluble pigment or oil-soluble dye, and among these, an oil-soluble dye is preferable.

  Among the oil-soluble dyes that can be used in the present invention, any yellow dye can be used. For example, phenols, naphthols, anilines, pyrazolones, pyridones, aryl or heteryl azo dyes having open-chain active methylene compounds as coupling components; for example, azomethine dyes having open-chain active methylene compounds as coupling components; Examples include methine dyes such as benzylidene dyes and monomethine oxonol dyes; quinone dyes such as naphthoquinone dyes and anthraquinone dyes; and other dye species such as quinophthalone dyes, nitro / nitroso dyes, acridines And dyes and acridinone dyes.

  Of the oil-soluble dyes usable in the present invention, any magenta dye can be used. For example, aryl or heteryl azo dyes having phenols, naphthols, anilines as coupling components; for example, azomethine dyes having pyrazolones, pyrazolotriazoles as coupling components; for example arylidene dyes, styryl dyes, merocyanine dyes, oxonol dyes Methine dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes and xanthene dyes; quinone dyes such as naphthoquinone, anthraquinone and anthrapyridone; condensed polycyclic dyes such as dioxazine dyes, etc. Can be mentioned.

  Among the oil-soluble dyes applicable to the present invention, any cyan dye can be used. For example, indoaniline dyes, indophenol dyes or azomethine dyes having pyrrolotriazoles as coupling components; polymethine dyes such as cyanine dyes, oxonol dyes, merocyanine dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, xanthene dyes Phthalocyanine dyes; anthraquinone dyes; for example, aryl or heteryl azo dyes having phenols, naphthols and anilines as coupling components; indigo / thioindigo dyes;

  Each of the above dyes may exhibit yellow, magenta, and cyan colors only after a part of chromophore (chromogenic atomic group) is dissociated. In this case, the counter cation may be an alkali metal or ammonium. Such inorganic cations may be used, and organic cations such as pyridinium and quaternary ammonium salts may be used, and furthermore, polymer cations having such a partial structure may be used.

Although not limited to the following, preferred specific examples include C.I. I. Solvent Black 3, 7, 27, 29 and 34; C.I. I. Solvent Yellow 14, 16, 19, 29, 30, 56, 82, 93 and 162; C.I. I. Solvent Red 1, 3, 8, 18, 24, 27, 43, 49, 51, 72, 73, 109, 122, 132 and 218; I. Solvent Violet 3; C.I. I. Solvent Blue 2,11,25,35,38,67 and 70; I. Solvent Green 3 and 7; I. Solvent orange 2; and the like.
Among these, particularly preferred are the Black Black PC-0850, Oil Black HBB, Oil Yellow 129, Oil Yellow 105, Oil Pink 312, Oil Red 5B, Oil Scallet 308, Vali Fast Blue chemistry 2606e Bile 2OSe 2B eO (Manufactured by Co., Ltd.), Aizen Spillon Blue GNH (manufactured by Hodogaya Chemical Co., Ltd.), Neopen Yellow 075, Neopen Magenta SE1378, Neopen Blue 808, Neopen Blue FF4012, and Neo42 Cy FF4012.
In the present invention, the oil-soluble dye may be used alone or in combination of several kinds.

Moreover, when using an oil-soluble dye as a colorant, other water-soluble dyes, disperse dyes, pigments, and other colorants can be used in combination as long as the effects of the present invention are not impaired.
In the present invention, a disperse dye can be used as long as it is soluble in a water-immiscible organic solvent. The disperse dye generally includes a water-soluble dye, but in the present invention, the disperse dye is preferably used as long as it is soluble in a water-immiscible organic solvent. Preferable specific examples of the disperse dye include C.I. I. Disperse Yellow 5,42,54,64,79,82,83,93,99, 100,119,122,124,126,160,184: 1,186,198,199,201,204,224 and 237 C. I. Disperse Orange 13, 29, 31: 1, 33, 49, 54, 55, 66, 73, 118, 119 and 163; I. Disperse Red 54, 60, 72, 73, 86, 88, 91, 92, 93, 111, 126, 127, 134, 135, 143, 145, 152, 153, 154, 159, 164, 167: 1,177 , 181, 204, 206, 207, 221, 239, 240, 258, 277, 278, 283, 311, 323, 343, 348, 356 and 362; I. Disperse Violet 33; C.I. I. Disperse Blue 56, 60, 73, 87, 113, 128, 143, 148, 154, 158, 165, 165: 1, 165: 2, 176, 183, 185, 197, 198, 201, 214, 224, 225 , 257, 266, 267, 287, 354, 358, 365 and 368; I. Disperse Green 6: 1 and 9;

  It is preferable that the colorant that can be used in the present invention is appropriately dispersed in the ink after being added to the ink composition of the present invention or the ink composition for inkjet recording. For dispersing the colorant, for example, a dispersion device 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, or a paint shaker can be used.

  It is also possible to add a dispersant when dispersing the colorant. The type of the dispersant is not particularly limited, but a polymer dispersant is preferably used, and 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. In the present invention, these dispersant and dispersion aid are preferably added in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of the colorant.

  In preparing the ink composition of the present invention, the colorant may be blended by adding directly with each component. However, in order to improve dispersibility, the solvent or the component (B) used in the present invention in advance or in combination as desired. (C) It can also mix | blend after adding to the dispersion medium like other polymeric compounds, and carrying out uniform dispersion | distribution or dissolution.

  In the present invention, in order to avoid the deterioration of the solvent resistance when the solvent remains in the cured image and the problem of VOC (Volatile Organic Compound) of the remaining solvent, the colorant contains the component (B). It is preferable to add and mix them in advance with any one of the polymerizable compounds containing or a mixture thereof. In consideration of only dispersibility, it is preferable to select a monomer having the lowest viscosity as the polymerizable compound used for the addition of the colorant.

These colorants may be used by appropriately selecting one type or two or more types according to the purpose of use of the ink composition.
When using a colorant such as a pigment that remains solid in the ink composition of the present invention, the average particle diameter of the colorant particles is preferably 0.005 to 0.5 μm, more preferably 0. It is preferable to set the colorant, the dispersing agent, the selection of the dispersion medium, the dispersion condition, and the filtration condition so as to be 0.01 to 0.45 μm, more preferably 0.015 to 0.4 μm. This particle size control is preferable because clogging of the head nozzle can be suppressed and ink storage stability, ink transparency, and curing sensitivity can be maintained.
The content of the colorant in the ink composition of the present invention is appropriately selected depending on the purpose of use. However, considering the ink physical properties and colorability, generally, the content of the colorant is 1 to 10 with respect to the total mass of the ink composition. It is preferable that it is mass%, and it is more preferable to contain 2-8 mass%.

(E) Sensitizing dye A sensitizing dye can be added to the ink composition of the present invention in order to accelerate the decomposition of (A) the polymerization initiator by actinic ray irradiation. A sensitizing dye absorbs specific actinic radiation and enters an electronically excited state. The sensitizing dye in an electronically excited state is brought into contact with the polymerization initiator to cause actions such as electron transfer, energy transfer, and heat generation, thereby causing a chemical change of the polymerization initiator, that is, decomposition, radical, acid or base. It promotes the generation of.

As the sensitizing dye, a compound corresponding to the wavelength of actinic radiation that generates an initiating species in the polymerization initiator (A) used in the ink composition may be used, but it is used for a curing reaction of a general ink composition. In view of the above, examples of preferred sensitizing dyes include those belonging to the following compounds and having an absorption wavelength in the 350 nm to 450 nm region.
Polynuclear aromatics (eg, pyrene, perylene, triphenylene), xanthenes (eg, fluorescein, eosin, erythrosine, rhodamine B, rose bengal), cyanines (eg, thiacarbocyanine, oxacarbocyanine), merocyanines ( For example, merocyanine, carbomerocyanine), thiazines (eg, thionine, methylene blue, toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, anthraquinone), squalium (eg, squalium) ), Coumarins (for example, 7-diethylamino-4-methylcoumarin), and the like.

  More preferable examples of the sensitizing dye include compounds represented by the following formulas (II) to (VI).

In the formula (II), A ¹ represents a sulfur atom or NR ⁵⁰ , R ⁵⁰ represents an alkyl group or an aryl group, and L ² forms a basic nucleus of the dye together with the adjacent A ¹ and the adjacent carbon atom. R ⁵¹ and R ⁵² each independently represent a hydrogen atom or a monovalent nonmetallic atomic group, and R ⁵¹ and R ⁵² may be bonded to each other to form an acidic nucleus of the dye. Good. W represents an oxygen atom or a sulfur atom.

In formula (III), Ar ¹ and Ar ² each independently represent an aryl group and are linked via a bond with —L ³ —. Here, L ³ represents —O— or —S—. W is synonymous with that shown in Formula (II).

In the formula (IV), A ² represents a sulfur atom or NR ⁵⁹ , L ⁴ represents a nonmetallic atomic group that forms a basic nucleus of a dye together with adjacent A ² and a carbon atom, R ⁵³ , R ⁵⁴ , R ⁵⁵ , R ⁵⁶ , R ⁵⁷ and R ⁵⁸ each independently represents a monovalent nonmetallic atomic group, and R ⁵⁹ represents an alkyl group or an aryl group.

In formula (V), A ³ and A ⁴ each independently represent —S— or —NR ⁶² — or —NR ⁶³ —, wherein R ⁶² and R ⁶³ each independently represent a substituted or unsubstituted alkyl group, substituted or represents an unsubstituted aryl group, L to ^5, L ⁶ are each independently, together with the adjacent a ^3, a ⁴ and adjacent carbon atoms represents a nonmetallic atom group necessary for forming a basic nucleus of a dye, R ⁶⁰ , R ⁶¹ each independently represents a hydrogen atom or a monovalent non-metallic atomic group, or may be bonded to each other to form an aliphatic or aromatic ring.

In formula (VI), R ⁶⁶ represents an aromatic ring or a hetero ring which may have a substituent, and A ⁵ represents an oxygen atom, a sulfur atom or ═NR ⁶⁷ . R ⁶⁴ , R ⁶⁵ and R ⁶⁷ each independently represent a hydrogen atom or a monovalent nonmetallic atomic group, and R ⁶⁷ and R ⁶⁴ , and R ⁶⁵ and R ⁶⁷ each represent an aliphatic or aromatic ring. Can be combined to form.

  Specific examples of the compounds represented by formulas (II) to (VI) include those shown below.

(F) Co-sensitizer The ink composition of the present invention can also contain a co-sensitizer. In the present invention, the co-sensitizer has functions such as further improving the sensitivity of the sensitizing dye to actinic radiation or suppressing polymerization inhibition of the polymerizable compound by oxygen.
Examples of such cosensitizers include amines such as M.I. R. Sander et al., “Journal of Polymer Society”, Vol. 10, 3173 (1972), Japanese Patent Publication No. 44-20189, Japanese Patent Publication No. 51-82102, Japanese Patent Publication No. 52-134692, Japanese Patent Publication No. 59-138205. No. 60-84305, JP-A 62-18537, JP-A 64-33104, Research Disclosure 33825, and the like. Specific examples include triethanolamine. P-dimethylaminobenzoic acid ethyl ester, p-formyldimethylaniline, p-methylthiodimethylaniline and the like.

  Other examples of co-sensitizers include thiols and sulfides, for example, thiol compounds described in JP-A-53-702, JP-B-55-500806, JP-A-5-142772, and JP-A-56 And the like. Specific examples include 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzoimidazole, 2-mercapto-4 (3H) -quinazoline, β-mercaptonaphthalene. Etc.

  Other examples include amino acid compounds (eg, N-phenylglycine), organometallic compounds described in Japanese Patent Publication No. 48-42965 (eg, tributyltin acetate), and hydrogen described in Japanese Patent Publication No. 55-34414. Donors, sulfur compounds described in JP-A-6-308727 (eg, trithiane), phosphorus compounds described in JP-A-6-250387 (diethylphosphite, etc.), Si-H described in JP-A-8-65779 , Ge—H compounds and the like.

(G) Other components Other components can be added to the ink composition of the present invention as necessary. Examples of other components include a polymerization inhibitor and a solvent.
A polymerization inhibitor may be added from the viewpoint of enhancing the storage stability. Further, when the ink composition of the present invention is used as an ink composition for ink jet recording, it is preferably discharged at a temperature in the range of 40 to 80 ° C. with a reduced viscosity, and also for preventing head clogging due to thermal polymerization. It is preferable to add a polymerization inhibitor. The polymerization inhibitor is preferably added in an amount of 200 to 20,000 ppm based on the total amount of the ink composition of the present invention. Examples of the polymerization inhibitor include hydroquinone, benzoquinone, p-methoxyphenol, TEMPO, TEMPOL, and cuperon Al.

Considering that i inkjet recording ink composition of the present invention is a radiation-curable ink composition, so that can react quickly and be cured immediately after the ink composition landed, it preferably contains no solvent. However, a predetermined solvent can be included as long as the curing rate of the ink composition is not affected. In the present invention, an organic solvent or water can be used as the solvent. In particular, the organic solvent can be added in order to improve the adhesion to the recording medium (support such as paper). The addition of an organic solvent is effective because the VOC problem can be avoided.
The amount of the organic solvent is, for example, 0.1 to 5% by mass, preferably 0.1 to 3% by mass with respect to the mass of the entire ink composition of the present invention.

  In addition to this, a known compound can be added to the ink composition of the present invention as necessary. For example, surfactants, leveling additives, matting agents, polyester resins for adjusting film properties, polyurethane resins, vinyl resins, acrylic resins, rubber resins, waxes and the like are appropriately selected and added. be able to. In order to improve the adhesion to a recording medium such as polyolefin or PET, it is also preferable to contain a tackifier that does not inhibit the polymerization. Specifically, a high molecular weight adhesive polymer described in JP-A-2001-49200, pages 5 to 6 (for example, (meth) acrylic acid and an alcohol having an alkyl group having 1 to 20 carbon atoms). An ester, a copolymer of (meth) acrylic acid and an alicyclic alcohol having 3 to 14 carbon atoms, a copolymer of an ester of (meth) acrylic acid and an aromatic alcohol having 6 to 14 carbon atoms), and polymerizability. Examples thereof include a low molecular weight tackifying resin having an unsaturated bond.

[Properties of ink composition]
As described above, the ink composition of the present invention contains the component (B), optionally (C) another polymerizable compound, (D) a colorant, and the like.
These components are preferably (D) a colorant, preferably 1 to 10% by mass, more preferably 2 to 8% by mass, and (B) a total polymerizable compound based on the total mass of the ink composition. , Preferably it is 5-97 mass%, More preferably, it is 30-95 mass%. (A) The polymerization initiator is preferably 0.01 to 35% by mass, more preferably 0.1 to 30% by mass, and still more preferably 0.5%, based on the total polymerizable compound containing the component (B). It is suitable to contain so that it may become -30 mass%.

The ink composition of the present invention is an ink composition for ink jet recording . The preferable physical property in such a use aspect is demonstrated.
When the ink composition is used as an ink for ink jet recording, the viscosity is preferably 7 to 30 mPa at the temperature at the time of ejection (for example, 40 to 80 ° C., preferably 25 to 50 ° C.) in consideration of the ejectability. · S, more preferably 7 to 25 mPa · s. For example, the viscosity of the ink composition of the present invention at room temperature (25 to 30 ° C.) is preferably 35 to 500 mPa · s, more preferably 35 to 200 mPa · s.
It is preferable that the composition ratio of the ink composition of the present invention is appropriately adjusted so that the viscosity is in the above range. By setting the viscosity at room temperature high, even when a porous recording medium is used, ink penetration into the recording medium can be avoided, and uncured monomers and odors can be reduced. Furthermore, ink bleeding at the time of ink droplet landing can be suppressed, and as a result, the image quality is improved.

  The surface tension of the ink composition of the present invention is preferably 20 to 30 mN / m, more preferably 23 to 28 mN / m. When recording on various recording media such as polyolefin, PET, coated paper, and non-coated paper, 20 mN / m or more is preferable from the viewpoint of bleeding and penetration, and the wettability is preferably 30 mN / m or less.

<Inkjet recording method>
The ink composition of the present invention, Ru is used for inkjet recording.
An ink jet recording method and an ink jet recording apparatus that can be suitably employed in the present invention will be described below.
The inkjet recording method of the present invention, the recording medium the ink composition of the present invention is used for Inkjet Symbol recording (support, recording material, etc.) in the ink composition discharged onto the recording medium This is a method of forming an image by irradiating actinic radiation and curing the ink.
More specifically, the inkjet recording method of the present invention comprises (a) a step of ejecting the ink composition of the present invention onto a recording medium, and (b) irradiating the ejected ink composition with actinic radiation. And a step of curing the ink composition.
By including the steps (a) and (b), the ink jet recording method of the present invention forms an image with the ink composition cured on the recording medium.

  (A) In the step of discharging the ink composition onto the recording medium, an ink jet recording apparatus described in detail below can be used.

[Inkjet recording device]
There is no restriction | limiting in particular as an inkjet recording device used for the recording method of this invention, The well-known inkjet recording device which can achieve the target resolution can be selected arbitrarily and can be used. That is, any known inkjet recording apparatus including a commercially available product can eject ink onto a recording medium in step (a) of the recording method of the present invention.
Examples of the ink jet recording apparatus that can be used in the present invention include an apparatus including an ink supply system, a temperature sensor, and an actinic radiation source.
The ink supply system includes, for example, an original tank containing the ink composition of the present invention, a supply pipe, an ink supply tank immediately before the inkjet head, a filter, and a piezo-type inkjet head. The piezo-type inkjet head has a multi-size dot of 1 to 100 pl, preferably 8 to 30 pl, for example, 320 × 320 to 4000 × 4000 dpi, preferably 400 × 400 to 1600 × 1600 dpi, and more preferably 720 × 720 dpi. It can drive so that it can discharge with the resolution of. In the present invention, dpi represents the number of dots per 2.54 cm.

  As described above, since it is desirable for the radiation curable ink to have a constant temperature for the ink to be ejected, heat insulation and heating can be performed from the ink supply tank to the inkjet head portion. The temperature control method is not particularly limited, but for example, it is preferable to provide a plurality of temperature sensors at each piping site and perform heating control according to the ink flow rate and the environmental temperature. The temperature sensor can be provided in the vicinity of the ink supply tank and the nozzle of the inkjet head. Moreover, it is preferable that the head unit to be heated is thermally shielded or insulated so that the apparatus main body is not affected by the temperature from the outside air. In order to shorten the printer start-up time required for heating or to reduce the loss of thermal energy, it is preferable to insulate from other parts and reduce the heat capacity of the entire heating unit.

Next, (b) the step of irradiating the discharged ink composition with actinic radiation to cure the ink composition will be described.
The ink composition ejected on the recording medium is cured by irradiation with actinic radiation. This is because (A) the polymerization initiator contained in the ink composition of the present invention is decomposed by irradiation with actinic radiation to generate initiating species such as radicals, acids and bases, and the function of the initiating species (B) This is because the polymerization reaction of the other polymerizable compound (C) used in combination with the components or as desired occurs and is accelerated, and the ink composition is cured. At this time, if (E) a sensitizing dye is present together with (A) a polymerization initiator in the ink composition, (E) the sensitizing dye in the system absorbs actinic radiation to be in an excited state, and (A) the polymerization initiator. (A) accelerates the decomposition of the polymerization initiator to achieve a more sensitive curing reaction.

Here, α rays, γ rays, electron beams, X rays, ultraviolet rays, visible light, infrared rays, or the like can be used as the active radiation used. Although the peak wavelength of actinic radiation is based also on the absorption characteristic of a sensitizing dye, it is preferable that it is 200-600 nm, for example, it is more preferable that it is 300-450 nm, and it is further more preferable that it is 350-420 nm.
In the present invention, the polymerization initiation system has sufficient sensitivity even with a low-power active radiation. Thus, the output of the active radiation is preferably 2,000 mJ / cm ² or less, more preferably from 10 to 2,000 mJ / cm ^2, more preferably, be 20 to 1,000 mJ / cm ² Particularly preferably, it is 50 to 800 mJ / cm ² .
The active radiation, the illumination intensity on the exposed surface is, for example, 10 to 2,000 mW / cm ^2, preferably, it is suitable to be irradiated at 20 to 1,000 mW / cm ^2.

Mercury lamps and gas / solid lasers are mainly used as actinic radiation sources, and mercury lamps and metal halide lamps are widely known as light sources used for curing UV photocurable ink jet recording inks. Yes. However, from the viewpoint of environmental protection, mercury-free is strongly desired, and replacement with a GaN-based semiconductor ultraviolet light-emitting device is very useful industrially and environmentally. Furthermore, LED (UV-LED) and LD (UV-LD) are small, have a long life, have high efficiency, and are low in cost, and are expected as light sources for photocurable ink jets.
Further, a light emitting diode (LED) and a laser diode (LD) can be used as the active radiation source. In particular, when an ultraviolet light source is required, an ultraviolet LED and an ultraviolet LD can be used. For example, Nichia Corporation has introduced a purple LED whose main emission spectrum has a wavelength between 365 nm and 420 nm. When even shorter wavelengths are required, US Pat. No. 6,084,250 discloses an LED that can emit actinic radiation centered between 300 nm and 370 nm. Other ultraviolet LEDs are also available and can emit radiation in different ultraviolet bands. The actinic radiation source particularly preferred in the present invention is a UV-LED, particularly preferably a UV-LED having a peak wavelength at 350 to 420 nm.
It is preferable that maximum illumination intensity of the LED on a recording medium is 10 to 2,000 mW / cm ^2, more preferably 20 to 1,000 mW / cm ^2, particularly preferably 50 to 800 mW / cm ² .

The ink composition of the present invention is suitably irradiated with such actinic radiation for, for example, 0.01 to 120 seconds, preferably 0.1 to 90 seconds.
Actinic radiation irradiation conditions and a basic irradiation method are disclosed in JP-A-60-132767. Specifically, the light source is provided on both sides of the head unit including the ink ejection device, and the head unit and the light source are scanned by a so-called shuttle method. Irradiation with actinic radiation takes a certain time (for example, 0.01 to 0.5 seconds, preferably 0.01 to 0.3 seconds, more preferably 0.01 to 0.15 seconds) after ink landing. Will be done. In this way, by controlling the time from ink landing to irradiation to an extremely short time, it is possible to prevent the ink that has landed on the recording medium from spreading before curing. Further, since the ink can be exposed to the porous recording medium before the ink penetrates to a deep part where the light source does not reach, the residual unreacted monomer can be suppressed, and as a result, the odor can be reduced. .
Further, the curing may be completed by another light source that is not driven. WO99 / 54415 pamphlet discloses a method using an optical fiber and a method of applying a collimated light source to a mirror surface provided on the side surface of the head unit and irradiating the recording unit with UV light as an irradiation method. The curing method can also be applied to the recording method of the present invention.

By adopting the ink jet recording method as described above, the dot diameter of the landed ink can be kept constant even on various recording media having different surface wettability, and the image quality is improved. In addition, in order to obtain a color image, it is preferable to superimpose in order from the color with the lowest brightness. By superimposing the inks in the order of low lightness, the irradiation line can easily reach the lower ink, and good curing sensitivity, reduction of residual monomers, reduction of odor, and improvement of adhesion can be expected. In addition, irradiation can be performed by discharging all colors and collectively exposing, but exposure for each color is preferable from the viewpoint of promoting curing.
In this way, the ink composition of the present invention is cured with high sensitivity by irradiation with actinic radiation, and forms a hydrophobic image on the surface of the recording medium.

<Lithographic printing plate and manufacturing method thereof>
A lithographic printing plate can be produced by applying and curing the ink composition of the present invention on a hydrophilic support using the inkjet recording method of the present invention. Next, a method for producing a lithographic printing plate comprising discharging an ink composition onto a lithographic printing plate support to form an image will be described.
The lithographic printing plate of the present invention has a hydrophilic support and a hydrophobic image formed on the hydrophilic support. This method for producing a lithographic printing plate includes the following steps.
(A) a step of discharging the ink composition of the present invention onto a hydrophilic support; and (b) irradiating the discharged ink composition with actinic radiation to cure the ink composition. Forming a hydrophobic image formed by curing the ink composition on the hydrophilic support;
That is, a lithographic printing plate can be produced in the same manner as the ink jet recording method of the present invention except that a support having a hydrophilic surface suitable for a lithographic printing plate support is used as the recording medium. it can.

[Hydrophilic support used for lithographic printing plates]
The planographic printing plate of the present invention has a hydrophilic support and a hydrophobic image formed on the surface of the support by the ink composition of the present invention.
As described above, the lithographic printing plate is formed by exposing a so-called PS plate having a structure in which a lipophilic photosensitive resin layer is provided on a hydrophilic support for images and solubilizing or curing the exposed portion to form an image. And the non-image area was dissolved and removed. By applying the ink jet recording method of the present invention, it is possible to easily produce a lithographic printing plate by injecting the ink composition directly onto the support surface according to digitized image information and curing it. It is a thing.

The lithographic printing plate support (recording medium) onto which the ink composition for inkjet recording of the present invention is discharged is not particularly limited, and any dimensionally stable plate-like support is used. However, in consideration of the image quality of the obtained printed matter, the surface is preferably a hydrophilic support.
The material used as the support can be used as the support as it is when it has hydrophilicity, and when it does not have hydrophilicity, the surface thereof may be subjected to water immersion treatment.
Materials used for the support include, for example, paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose diacetate) Cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), paper or plastic film on which the above-mentioned metal is laminated or vapor-deposited, etc. Is mentioned. Preferable supports include a polyester film and an aluminum plate. Among these, an aluminum plate that has good dimensional stability and is relatively inexpensive is preferable.

  The aluminum plate is a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, or a plastic laminated on a thin film of aluminum or an aluminum alloy. Examples of foreign elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of foreign elements in the alloy is preferably 10% by mass or less. In the present invention, a pure aluminum plate is preferable. However, since completely pure aluminum is difficult to manufacture in terms of refining technology, it may contain a slightly different element. The composition of the aluminum plate is not specified, and a known material can be used as appropriate.

The thickness of the support is preferably 0.1 to 0.6 mm, and more preferably 0.15 to 0.4 mm.
Prior to using the aluminum plate, it is preferable to perform surface treatment such as roughening treatment or anodizing treatment. By the surface treatment, it is easy to improve hydrophilicity and secure adhesion between the image recording layer and the support. Prior to roughening the aluminum plate, a degreasing treatment with a surfactant, an organic solvent, an alkaline aqueous solution or the like for removing rolling oil on the surface is performed as desired.

The surface roughening treatment of the aluminum plate is performed by various methods. For example, mechanical surface roughening treatment, electrochemical surface roughening treatment (surface roughening treatment for dissolving the surface electrochemically), chemical treatment, etc. Surface roughening treatment (roughening treatment that chemically selectively dissolves the surface).
As a method for the mechanical surface roughening treatment, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, or a buff polishing method can be used. Also, a transfer method in which the uneven shape is transferred with a roll provided with unevenness in the aluminum rolling step may be used.
Examples of the electrochemical surface roughening treatment include a method in which an alternating current or a direct current is used in an electrolytic solution containing an acid such as hydrochloric acid or nitric acid. Another example is a method using a mixed acid as described in JP-A-54-63902.
The surface-roughened aluminum plate is subjected to an alkali etching treatment using an aqueous solution of potassium hydroxide, sodium hydroxide or the like, if necessary, further neutralized, and if desired, wear resistant. In order to increase the anodic oxidation treatment.

As the electrolyte used for the anodizing treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used. In general, sulfuric acid, hydrochloric acid, oxalic acid, chromic acid or a mixed acid thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of electrolyte.
The conditions for anodizing treatment vary depending on the electrolyte used and cannot be specified in general. In general, however, the electrolyte concentration is 1 to 80% by mass solution, the liquid temperature is 5 to 70 ° C., and the current density is 5 to 60 A / day. dm ² , voltage 1 to 100 V, and electrolysis time 10 seconds to 5 minutes are preferable. The amount of the anodized film formed is preferably from 1.0 to 5.0 g / m ^2, and more preferably 1.5 to 4.0 g / m ^2. Within this range, good printing durability and good scratch resistance of the non-image area of the lithographic printing plate can be obtained, which is preferable.

  As a support used in the present invention, a substrate that has been surface-treated as described above and has an anodized film may be used as it is, but the adhesion to the upper layer, hydrophilicity, dirt resistance, etc. are further improved. Therefore, if necessary, the micropore enlargement treatment and sealing treatment of the anodized film described in JP-A-2001-253181 and JP-A-2001-322365, and an aqueous solution containing a hydrophilic compound The surface hydrophilization treatment to be immersed can be appropriately selected and performed. Of course, these enlargement processing and sealing processing are not limited to those described above, and any conventionally known method can be performed.

[Sealing treatment]
Sealing treatment includes vapor sealing, single treatment with zirconic fluoride, treatment with an aqueous solution containing an inorganic fluorine compound such as treatment with sodium fluoride, vapor sealing with addition of lithium chloride, sealing with hot water. Hole processing is also possible.
Of these, sealing treatment with an aqueous solution containing an inorganic fluorine compound, sealing treatment with water vapor, and sealing treatment with hot water are preferable. Each will be described below.

(Sealing treatment with an aqueous solution containing an inorganic fluorine compound)
As the inorganic fluorine compound used for the sealing treatment with an aqueous solution containing an inorganic fluorine compound, a metal fluoride is preferably exemplified.
Specifically, for example, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, sodium fluoride zirconate, potassium fluoride zirconate, sodium fluoride titanate, potassium fluoride titanate, zircon fluoride Ammonium acid, ammonium fluoride titanate, potassium fluoride titanate, fluorinated zirconate, fluorinated titanate, hexafluorosilicic acid, nickel fluoride, iron fluoride, phosphor fluoride, ammonium fluoride phosphate It is done. Of these, sodium fluorinated zirconate, sodium fluorinated titanate, fluorinated zirconic acid, and fluorinated titanic acid are preferable.

The concentration of the inorganic fluorine compound in the aqueous solution is preferably 0.01% by mass or more, and more preferably 0.05% by mass or more in terms of sufficiently sealing the micropores of the anodized film. Further, in terms of stain resistance, the content is preferably 1% by mass or less, and more preferably 0.5% by mass or less.
It is preferable that the aqueous solution containing the inorganic fluorine compound further contains a phosphate compound. The inclusion of a phosphate compound is preferable because the hydrophilicity of the surface of the anodized film is improved, and the on-press developability and stain resistance can be improved.

Suitable examples of the phosphate compound include phosphates of metals such as alkali metals and alkaline earth metals.
Specifically, for example, zinc phosphate, aluminum phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, monoammonium phosphate, monopotassium phosphate, monosodium phosphate, dihydrogen phosphate Potassium, dipotassium hydrogen phosphate, calcium phosphate, sodium ammonium hydrogen phosphate, magnesium hydrogen phosphate, magnesium phosphate, ferrous phosphate, ferric phosphate, sodium dihydrogen phosphate, sodium phosphate, hydrogen phosphate Disodium, lead phosphate, diammonium phosphate, calcium dihydrogen phosphate, lithium phosphate, phosphotungstic acid, ammonium phosphotungstate, sodium phosphotungstate, ammonium phosphomolybdate, sodium phosphomolybdate, sodium phosphite , Tripolyphosphate Potassium, and sodium pyrophosphate. Of these, sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate are preferable.
The combination of the inorganic fluorine compound and the phosphate compound is not particularly limited, but the aqueous solution contains at least sodium zirconate fluoride as the inorganic fluorine compound and contains at least sodium dihydrogen phosphate as the phosphate compound. It is preferable.
The concentration of the phosphate compound in the aqueous solution is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, from the viewpoint of improving on-press developability and stain resistance. Moreover, it is preferable that it is 20 mass% or less at a soluble point, and it is more preferable that it is 5 mass% or less.

The ratio of each compound in the aqueous solution is not particularly limited, but the mass ratio of the inorganic fluorine compound and the phosphate compound is preferably 1/200 to 10/1, and preferably 1/30 to 2/1. Is more preferable.
The temperature of the aqueous solution is preferably 20 ° C. or higher, more preferably 40 ° C. or higher, 100 ° C. or lower, more preferably 80 ° C. or lower.
The aqueous solution preferably has a pH of 1 or more, more preferably has a pH of 2 or more, preferably has a pH of 11 or less, and more preferably has a pH of 5 or less.
The method for sealing with an aqueous solution containing an inorganic fluorine compound is not particularly limited, and examples thereof include an immersion method and a spray method. These may be used alone or in combination, or may be used in combination of two or more.
Of these, the dipping method is preferred. When processing using the dipping method, the processing time is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, and 20 seconds or shorter. More preferred.

(Sealing with water vapor)
Examples of the sealing treatment with water vapor include a method of bringing pressurized or normal pressure water vapor into contact with the anodized film continuously or discontinuously.
The temperature of the water vapor is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, and preferably 105 ° C. or lower.
The pressure of the water vapor is preferably in the range (1.008 × 10 ^{5 to} 1.043 × 10 ⁵ Pa) from (atmospheric pressure−50 mmAq) to (atmospheric pressure + 300 mmAq).
The time for which the water vapor is contacted is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, and more preferably 20 seconds or shorter.

(Sealing treatment with hot water)
Examples of the sealing treatment with water vapor include a method in which an aluminum plate on which an anodized film is formed is immersed in hot water.
The hot water may contain an inorganic salt (for example, phosphate) or an organic salt.
The temperature of the hot water is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, and preferably 100 ° C. or lower.
Further, the time of immersion in hot water is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, more preferably 20 seconds or shorter.
Examples of the hydrophilization treatment used in the present invention include US Pat. Nos. 2,714,066, 3,181,461, 3,280,734 and 3,902,734. There is an alkali metal silicate method as described in the book. In this method, the support is immersed in an aqueous solution such as sodium silicate or electrolytically treated. In addition, the treatment with potassium zirconate fluoride described in JP-B 36-22063, U.S. Pat. Nos. 3,276,868, 4,153,461 and 4,689, And a method of treating with polyvinylphosphonic acid as described in each specification of No.272.
In the present invention, the support preferably has a center line average roughness of 0.10 to 1.2 μm. Within this range, good adhesion to the image recording layer, good printing durability and good stain resistance are obtained, which is preferable.

(A) Step of discharging the ink composition onto the hydrophilic support First, the ink composition of the present invention is discharged onto the surface of the hydrophilic support. At this time, the ink composition is preferably heated to 40 to 80 ° C., more preferably 25 to 50 ° C., and the viscosity of the ink composition is preferably lowered to 7 to 30 mPa · s, more preferably 7 to 25 mPa · s. It is preferable to discharge after a short time. In particular, it is preferable to use an ink composition having an ink viscosity of 35 to 500 mPa · s at 25 ° C. because a great effect can be obtained. By using this method, high ejection stability can be realized.
A radiation curable ink composition such as the ink composition of the present invention generally has a higher viscosity than a water-based ink usually used in ink jet recording inks, and therefore has a large viscosity fluctuation due to temperature fluctuations during ejection. The ink viscosity fluctuation has a great influence on the change of the droplet size and the change of the droplet discharge speed, and causes the image quality deterioration. Therefore, it is necessary to keep the temperature of the ink at the time of ejection as constant as possible. Therefore, in the present invention, it is appropriate that the temperature control range is set to ± 5 ° C. of the set temperature, preferably ± 2 ° C. of the set temperature, more preferably set temperature ± 1 ° C.

(B) A step of forming a hydrophobic image by irradiating the ejected ink composition with actinic radiation and curing the ink composition. The ink composition ejected on the surface of the hydrophilic support is actinic radiation. Is cured by irradiation. The details of the curing mechanism are the same as those described in the ink jet recording method.
By adopting the ink jet recording method as described above, the dot diameter of the landed ink can be kept constant even for various lithographic printing plate supports having different surface wettability, and the image quality is improved. . In this manner, the ink composition of the present invention is cured by irradiation with actinic radiation, and a hydrophobic image is formed on the surface of the hydrophilic support to obtain a lithographic printing plate.

Here, the actinic radiation source used for curing the ink or preferred irradiation conditions thereof are also the same as those described in the ink jet recording method.
The ink composition of the present invention is cured with high sensitivity by actinic radiation, and can form a hydrophobic region excellent in adhesion to the support and film quality, so that the obtained lithographic printing plate has high image quality. Excellent printing durability.
It goes without saying that the ink composition of the present invention is useful not only for forming the image portion of such a lithographic printing plate but also as a commonly used ink composition.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the embodiments in these examples.
The following examples relate to UV inkjet inks of each color.
[Example 1]
The following components were stirred with a high-speed water-cooled stirrer to obtain a cyan UV inkjet ink.
(Cyan ink composition)
-Specific polymerizable compound B-6: (B) component 15.4 parts-Actilane 421 36.0 parts (*: Acrycros acrylate monomer: (C) component)
・ Photomer 2017 (UV diluent manufactured by ECchem) 20.0 parts ・ Solsperse 32000 (dispersant made by Noveon) 0.4 part ・ 3.6 parts Irgalite Blue GLVO (Pigment made by Ciba Specialty Chemicals: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 part ・ Rapi-Cure DVE-3 8.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

* Activane 421 is propoxylated neopentyl glycol diacrylate (bifunctional acrylate).

(Evaluation of ink)
The obtained cyan ink composition was printed on a polyvinyl chloride sheet and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The ink was cured to obtain a printed matter.
At this time, the following evaluation was performed.
The exposure energy in curing was measured with a light quantity integrator (UV PowerMAP manufactured by EIT). As a result, the cumulative exposure amount of ultraviolet rays on the sheet was about 330 mJ / cm ² , and it was confirmed that the sheet was cured with high sensitivity.
The curability was evaluated by palpation of the image area after the printed material was cured with this ink. As a result, it was confirmed that the tackiness after curing was completely lost and the curability was excellent.
The adhesiveness and flexibility with the recording medium were evaluated by a cross hatch test (EN ISO 2409), and showed high adhesiveness with class 4B. Further, the flexibility was evaluated by the degree of cracks generated in the cured film after bending the sheet 10 times. This bending test is performed in a five-step evaluation with 5 points indicating a state in which no cracks occur, and 3 or more points are evaluated as having no practical problems. As a result, slight cracks that do not affect the printed image are obtained. It was only admitted that the generation of 4 was evaluated.
The results are shown in Table 1 below.

(Example 2)
The following components were stirred with a high-speed water-cooled stirrer to obtain a magenta UV inkjet ink.
(Magenta ink composition)
-Specific polymerizable compound B-6: 10.4 parts of (B) component-Specific polymerizable compound B-15: 3.0 parts of (B) component- 33.8 parts of Actilane 421 (The above acrylate monomer manufactured by Akcros: ( C) Component)
・ Photomer 2017 (UV diluent made by EChem) 20.0 parts ・ Solsperse 32000 (dispersant made by Noveon) 0.4 part ・ 3.6 parts Cinquasia Magenta RT-355D (pigment made by Ciba Specialty Chemicals: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 part ・ Rapi-Cure DVE-3 8.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

  The produced magenta ink was printed on a polyvinyl chloride sheet, and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

(Example 3)
The following components were stirred with a high-speed water-cooled stirrer to obtain a yellow UV inkjet ink.
(Yellow color ink composition)
Specific polymerizable compound B-7: (B) component 7.4 parts Actylane 421 48.0 parts (The above-mentioned Akcros acrylate monomer: (C) component)
-Photomer 2017 (UV diluent manufactured by EChem) 20.0 parts-Solsperse 32000 (dispersant made by Noveon) 0.4 parts-3.6 parts of Chromophthal Yellow LA (pigment manufactured by Ciba Specialty Chemicals)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 parts ・ Rapi-Cure DVE-3 4.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

  The produced yellow ink was printed on a polyvinyl chloride sheet and irradiated by passing it through a light beam of an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

Example 4
The following components were stirred with a high-speed water-cooled stirrer to obtain a black UV inkjet ink.
(Black ink composition)
-Specific polymerizable compound B-6: (B) component 21.4 parts-Actilane 421 34.0 parts (the above-mentioned Akcros acrylate monomer: (C) component)
-Photomer 2017 (UV diluent manufactured by EChem) 20.0 parts-Solsperse 32000 (dispersant made by Noveon) 0.4 parts-2.6 parts Microlith Black C-K (Pigments manufactured by Ciba Specialty Chemicals: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 parts ・ Rapi-Cure DVE-3 5.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

  The produced black ink was printed on a polyvinyl chloride sheet and irradiated by passing it through a light beam of an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

(Example 5)
The following components were stirred with a high-speed water-cooled stirrer to obtain a cyan UV inkjet ink.
(Cyan ink composition)
Specific polymerizable compound B-1: (B) component 25.4 parts Actylane 422 48.0 parts (*: Akcros acrylate monomer: (C) component)
-Solsperse 32000 (Noveon dispersant) 0.4 part-Irgalite Blue GLVO 3.6 parts (Ciba Specialty Chemicals pigment: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 parts ・ Rapi-Cure DVE-2 6.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

* Activane 422 is dipropylene glycol diacrylate (bifunctional acrylate).

  The produced cyan ink was printed on a polyvinyl chloride sheet and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

(Example 6)
The following components were stirred with a high-speed water-cooled stirrer to obtain a cyan UV inkjet ink.
(Cyan ink composition)
-Specific polymerizable compound B-6: (B) component 15.0 parts-KAYARAD HDDA 2.6 parts (* Nippon Kayaku acrylate monomer: (C) component)
-Actilane 421 61.0 parts (the acrylate monomer manufactured by Akcros: component (C))
・ Solsperse 32000 (Noveon dispersant) 0.4 part ・ Solsperse 5000 (Noveon dispersant) 0.05 part ・ Irgalite Blue GLVO 1.4 part (Ciba Specialty Chemicals pigment)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 parts ・ Rapi-Cure DVE-3 5.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.0 parts ・ Benzophenone (photoinitiator: (A) component) 2.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals Co., Ltd.) Initiator: (A) component)
Byk 307 (antifoam manufactured by BYK Chemie) 0.5 part * KAYARAD HDDA is 1,6-hexanediol diacrylate (bifunctional acrylate).

  The produced cyan ink was printed on a polyvinyl chloride sheet and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

(Comparative Example 1)
The following components were stirred with a high-speed water-cooled stirrer to obtain a cyan UV inkjet ink.
(Cyan ink composition)
-Light acrylate LA 15.4 parts (*: Kyoeisha Chemical acrylate monomer: Component (C))
-Actilane 421 36.0 parts (the acrylate monomer manufactured by Akcros Co., Ltd .: component (C))
・ Photomer 2017 (UV diluent manufactured by ECchem) 20.0 parts ・ Solsperse 32000 (dispersant made by Noveon) 0.4 part ・ 3.6 parts Irgalite Blue GLVO (Pigment made by Ciba Specialty Chemicals: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 part ・ Rapi-Cure DVE-3 8.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
-Byk 307 (antifoaming agent manufactured by BYK Chemie) 0.05 parts * Light acrylate LA is a lauryl acrylate (monofunctional acrylate).

  The produced cyan ink was printed on a polyvinyl chloride sheet and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

(Comparative Example 2)
The following components were stirred with a high-speed water-cooled stirrer to obtain a cyan UV inkjet ink.
(Cyan ink composition)
-Actilane 421 51.4 parts (the acrylate monomer manufactured by Akcros Co., Ltd .: component (C))
・ Photomer 2017 (UV diluent manufactured by EChem) 20.0 parts ・ Solsperse 32000 (dispersant made by Noveon) 0.4 part ・ 3.6 parts Irgarite Blue GLVO (pigment made by Ciba Specialty Chemicals: (D) component)
・ Genorad 16 (stabilizer manufactured by Rahn) 0.05 part ・ Rapi-Cure DVE-3 8.0 parts (vinyl ether manufactured by ISP Europe: component (C))
・ Lucirin TPO (BASF photoinitiator: (A) component) 8.5 parts ・ Benzophenone (photoinitiator: (A) component) 4.0 parts ・ Irgacure 184 4.0 parts (Ciba Specialty Chemicals, Inc. Initiator: (A) component)
・ Byk 307 (defoamer manufactured by BYK Chemie) 0.05 parts

  The produced cyan ink was printed on a polyvinyl chloride sheet and irradiated by passing it through an iron-doped ultraviolet lamp (power 120 W / cm) at a speed of 40 m / min. The printed matter with this ink was evaluated in the same manner as in Example 1. The results are shown in Table 1 below.

As is apparent from Table 1, each of the ink compositions of Examples 1 to 6 was cured with high sensitivity, and any of the curability of the image area, the adhesion to the recording medium, and the flexibility of the image (film) It was also excellent.
On the other hand, the ink composition of Comparative Example 1 which does not contain the component (B) and contains the monofunctional acrylate as the polymerizable compound is not sufficiently curable, and does not contain the component (B) and contains the bifunctional acrylate. The ink composition of Comparative Example 2 as a main component showed good curability, but because the cured film was not sufficiently flexible and adhesive, the cured film was markedly cracked by bending the sheet, causing problems in practical use. It was a level to become.

(Example 7)
(Production of support)
Si: 0.06 mass%, Fe: 0.30 mass%, Cu: 0.025 mass%, Mn: 0.001 mass%, Mg: 0.001 mass%, Zn: 0.001 mass%, Ti: It contains 0.03% by mass, and the balance is prepared by using an aluminum alloy of Al and inevitable impurities. After the molten metal treatment and filtration, an ingot having a thickness of 500 mm and a width of 1200 mm is obtained by a DC casting method. Produced. After the surface was shaved with a chamfering machine with an average thickness of 10 mm, it was kept soaked at 550 ° C. for about 5 hours, and when the temperature dropped to 400 ° C., rolling with a thickness of 2.7 mm using a hot rolling mill A board was used. Furthermore, after performing heat processing using a continuous annealing machine at 500 degreeC, it finished by cold rolling to 0.24 mm in thickness, and obtained the aluminum plate of JIS1050 material. The obtained aluminum had an average crystal grain size with a minor axis of 50 μm and a major axis of 300 μm. After making this aluminum plate width 1030mm, it used for the surface treatment shown below and created the aluminum support body.

<Surface treatment>
In the surface treatment, the following various treatments (a) to (j) were continuously performed. In addition, after each process and water washing, the liquid draining was performed with the nip roller.
(A) Mechanical surface roughening treatment While supplying a suspension of a polishing agent (pumice) having a specific gravity of 1.12 and water as a polishing slurry liquid to the surface of the aluminum plate, mechanical roughening is performed by a rotating nylon brush. Surface treatment was performed. The average particle size of the abrasive was 30 μm, and the maximum particle size was 100 μm. The material of the nylon brush was 6 · 10 nylon, the hair length was 45 mm, and the hair diameter was 0.3 mm. The nylon brush was planted so as to be dense by making a hole in a stainless steel tube having a diameter of 300 mm. Three rotating brushes were used. The distance between the two support rollers (φ200 mm) at the bottom of the brush was 300 mm. The brush roller was pressed until the load of the drive motor for rotating the brush became 7 kW plus with respect to the load before the brush roller was pressed against the aluminum plate. The rotating direction of the brush was the same as the moving direction of the aluminum plate. The rotation speed of the brush was 200 rpm.
(B) Alkali etching treatment The aluminum plate obtained above was subjected to an etching treatment by spraying using an aqueous solution having a caustic soda concentration of 2.6% by mass, an aluminum ion concentration of 6.5% by mass and a temperature of 70 ° C. / M ² dissolved. Then, water washing by spraying was performed.
(C) Desmutting treatment The desmutting treatment was performed by spraying with a 1% by mass aqueous solution of nitric acid at a temperature of 30 ° C. (containing 0.5% by mass of aluminum ions), and then washed with water by spraying. The nitric acid aqueous solution used for the desmut treatment was a waste liquid from a process of performing an electrochemical surface roughening treatment using alternating current in a nitric acid aqueous solution.

(D) Electrochemical roughening treatment An electrochemical roughening treatment was carried out continuously using an alternating voltage of 60 Hz. The electrolytic solution at this time was a 10.5 g / L aqueous solution of nitric acid (containing 5 g / L of aluminum ions and 0.007% by mass of ammonium ions) at a liquid temperature of 50 ° C. AC power supply waveform is 0.8 msec until the current value reaches the peak from zero, duty ratio is 1: 1, and trapezoidal rectangular wave alternating current is used to perform electrochemical surface roughening treatment with the carbon electrode as the counter electrode. went. Ferrite was used for the auxiliary anode.
The current density was 30 A / dm ² at the peak current value, and the amount of electricity was 220 C / dm ² in terms of the total amount of electricity when the aluminum plate was the anode. 5% of the current flowing from the power source was shunted to the auxiliary anode. Then, water washing by spraying was performed.
(E) Alkaline etching treatment The aluminum plate was subjected to etching treatment at 32 ° C. using an aqueous solution having a caustic soda concentration of 26% by mass and an aluminum ion concentration of 6.5% by mass to dissolve the aluminum plate by 0.50 g / m ² . Removes the smut component mainly composed of aluminum hydroxide that was generated when electrochemical roughening treatment was performed using the alternating current of the previous stage, and also melted the edge part of the generated pit to smooth the edge part. did. Then, water washing by spraying was performed.
(F) Desmut treatment Desmut treatment was performed by spraying with a 15% by weight aqueous solution of nitric acid at a temperature of 30 ° C. (containing 4.5% by weight of aluminum ions), and then washed with water by spraying. The nitric acid aqueous solution used in the desmut was the waste liquid from the step of electrochemical surface roughening using alternating current in the nitric acid aqueous solution.

(G) Electrochemical roughening treatment An electrochemical roughening treatment was performed continuously using an alternating voltage of 60 Hz. The electrolytic solution at this time was a hydrochloric acid 5.0 g / L aqueous solution (containing 5 g / L of aluminum ions) at a temperature of 35 ° C. The AC power supply waveform is subjected to electrochemical surface roughening using a carbon electrode as a counter electrode, using a trapezoidal trapezoidal wave alternating current with a time until the current value reaches a peak from zero for 0.8 msec, a duty ratio of 1: 1. went. Ferrite was used for the auxiliary anode.
The current density was 25 A / dm ² at the peak current value, and the amount of electricity was 50 C / dm ² in terms of the total amount of electricity when the aluminum plate was the anode. Then, water washing by spraying was performed.
(H) Alkaline etching treatment The aluminum plate was subjected to an etching treatment at 32 ° C. using an aqueous solution having a caustic soda concentration of 26% by mass and an aluminum ion concentration of 6.5% by mass to dissolve the aluminum plate by 0.12 g / m ² . Removes the smut component mainly composed of aluminum hydroxide that was generated when electrochemical roughening treatment was performed using the alternating current of the previous stage, and also melted the edge part of the generated pit to smooth the edge part. did. Then, water washing by spraying was performed.
(I) Desmutting treatment A desmutting treatment by spraying was performed with a 25% by weight aqueous solution of sulfuric acid at a temperature of 60 ° C. (containing 0.5% by weight of aluminum ions), followed by washing with water by spraying.
(J) Anodizing treatment Anodizing treatment is performed using an anodizing apparatus (first and second electrolysis section length 6 m, first and second feeding section length 3 m, first and second feeding section length 2.4 m each). It was. Sulfuric acid was used as the electrolytic solution supplied to the first and second electrolysis units. All electrolytes had a sulfuric acid concentration of 50 g / L (containing 0.5 mass% of aluminum ions) and a temperature of 20 ° C. Then, water washing by spraying was performed. The final oxide film amount was 2.7 g / m ² .

(Preparation and evaluation of lithographic printing plates)
Printing was performed with the ink composition of Example 1 on the aluminum support prepared above, and an image was formed and cured in the same manner as in Example 1. This was used as a planographic printing plate to evaluate the image.
a. Evaluation of Image A lithographic printing plate produced using the ink composition of Example 1 was applied to a Heidel KOR-D machine, and dampened with ink [VALUES-G Beni for Sheetfed (Dainippon Ink Co., Ltd.)]. Water [Ecocity 2 (Fuji Photo Film Co., Ltd.)] was supplied for printing. The printed matter after printing 100 sheets was visually evaluated. As a result, it was confirmed that the image was a good image with no white spots in the image area and no stain in the non-image area.

b. Evaluation of printing durability When printing is continued as it is, 10,000 or more high-quality prints free from white spots in the image area and stains in the non-image area are obtained, and the printing durability is at a level where there is no practical problem. I confirmed that there was.

Claims (10)

A polymerization initiator;
And at least one compound selected from the group in the molecular consist (meth) acrylic acid ester or amide having a carboxyl group and one (meth) acryloyl group,
An ink composition for ink-jet recording, comprising: The ink composition for inkjet recording according to claim 1, wherein the content of the compound is 5 to 45% by mass with respect to the mass of the entire ink composition. The ink composition for ink jet recording according to claim 1 or 2 , comprising a colorant. The ink composition for inkjet recording according to claim 3 , wherein the colorant is a pigment. The content of the coloring agent, the mass of the entire ink composition, inkjet recording ink composition according to any one of claims 3 to 4 1 to 10% by weight.   The ink composition for ink jet recording according to any one of claims 1 to 5, further comprising a polymerization inhibitor. The ink composition for ink jet recording according to claim 6, wherein the content of the polymerization inhibitor is in the range of 200 to 20,000 ppm with respect to the total amount of the ink composition. (A) a step of discharging the ink composition according to any one of claims 1 to 7 onto a recording medium; and (b) an ink by irradiating the discharged ink composition with actinic radiation. Curing the composition;
An inkjet recording method comprising: (A) a step of discharging the ink composition according to any one of claims 1 to 7 onto a hydrophilic support; and (b) irradiating the discharged ink composition with actinic radiation. A step of curing the ink composition to form a hydrophobic image on the hydrophilic support by curing the ink composition;
A method for producing a lithographic printing plate comprising A lithographic printing plate produced by the method for producing a lithographic printing plate according to claim 9 .