JP2012000934A - Active ray-curable inkjet recording media and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active ray-curable inkjet recording media having high color-developing properties, high definition, and excellent image sharpness, and an active ray-curable inkjet recording method.SOLUTION: The are provided an active ray-curable inkjet recording media characterized in that an ink-retaining layer is a non-absorption layer containing at least one kind of the following compounds (A) and (B), and a recording method using the media: (A) acrylic resin by soap-free polymerization; and (B) fluorocarbon resin water and oil repellent.

Description

  In the present invention, an ink holding layer is applied to at least one surface of a non-absorbent substrate used in a recording method in which an ink composition is used for printing with an actinic ray curable ink composition and then the ink composition is cured with actinic rays. More specifically, the present invention relates to an actinic ray curable ink jet recording medium and a recording method that have high color developability, high definition, and excellent image sharpness.

  In recent years, since the inkjet method can print high-definition images at low cost, it has dramatically expanded for home use, which mainly outputs relatively small-sized photographs. This high-definition print quality has been achieved by a combination of high-definition inkjet printers and dedicated media that matches this.

  On the other hand, the inkjet recording method is also applied to business applications such as sign & display, signboard, and printing because it can be easily increased in size as compared with other methods. In such business applications, printing on a very wide variety of media is necessary. For example, a phase change ink jet method using a solid wax ink at room temperature, and an ink mainly containing an organic solvent as a medium. Such as solvent-based ink jet method in which solution is impregnated and forcibly dried with heat or wind, and UV curable ink jet method in which ultraviolet light (UV) is used to polymerize ink printed on a medium using ultraviolet curable ink. In many cases, an ink jet method that does not depend on media is used.

  Among such ink jet systems that do not depend on media, actinic rays typified by the above-described UV curable ink jet system, compared with a phase change type ink jet system that is relatively weak to scratching and a solvent type ink jet system with a strong solvent odor. The curable ink jet method is attracting attention because it has good quick-drying, odor, and weather resistance, and moreover, in recent years, energy efficiency has become more dominant due to LED UV irradiation devices. Such an actinic ray curable ink jet system is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-358769 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-153193 (Patent Document 2), which are UV curable ink jet printers using UVLEDs. JP-A-2004-34543 (Patent Document 3) discloses a cationic curable active energy ray-curable ink, and JP-A-2009-227822 (Patent Document 4) discloses a microencapsulated UV-curable resin emulsion. Ink and the like containing is disclosed.

  In such an actinic radiation curable ink jet ink, the main component is a polymerizable monomer component in addition to the pigment color material and the polymerization initiator, so the dispersion stability of the pigment color material is relatively poor, and the inkjet head is blocked. However, there has been no resolution as high as 600 dpi for home use as described above, but in recent years, with the evolution of printers, high-resolution actinic radiation curable inkjet printers exceeding 1200 dpi have been developed. It has been put on the market, and it has become possible to obtain higher-definition print quality than before.

  However, since the ink is mainly composed of a polymerizable monomer component that is polymerized by actinic rays, the surface tension is low, and when held on a non-absorbent medium, the ink dots after printing are remarkably spread even when printing at high resolution. Therefore, there is a problem that it is impossible to obtain a print quality with high definition and good image sharpness.

  As methods for controlling ink dots after printing on an ink jet recording medium using oil-based ink or water-based ink, Japanese Patent Application Laid-Open No. 08-300808 (Patent Document 5) and Japanese Patent Application Laid-Open No. 10-114141 (Patent Document 6). JP-A-2004-291437 (Patent Document 7) and JP-A-2007-182019 (Patent Document 8) disclose that the ink absorbing layer contains a water repellent or sizing agent of silicone resin or fluororesin. Has been.

  However, these publications are recording media on the premise that all printed ink is absorbed by a coated ink absorbing layer or paper base material, and printing on such recording media is performed using an actinic ray curable ink jet method. In this case, the ink permeates and cures in the ink absorption layer or paper layer having low transparency, resulting in a decrease in color developability, or when the ink penetrates into the ink absorption layer or paper layer due to the low ink surface tension described above. The dots spread, making it difficult to achieve both desired color development and image sharpness.

JP 2004-358769 A JP 2005-153193 A JP 2004-34543 A JP 2009-227822 A Japanese Patent Laid-Open No. 08-300808 JP-A-10-114141 JP 2004-291437 A JP 2007-182019 A

  An object of the present invention is to use an ink holding layer on at least one surface of a non-absorbing substrate, which is used in a recording method in which an ink composition is used for printing with an actinic ray curable ink composition and then the ink composition is cured with actinic rays. It is an object of the present invention to provide an actinic ray curable ink jet recording medium and a recording method which have high color developability, high definition and excellent image sharpness.

The above-mentioned subject is achieved by the following invention.
(1) An ink holding layer is applied to at least one surface of a non-absorbent substrate used in a recording method in which an ink composition is used for printing with an actinic ray curable ink composition and then the ink composition is cured with actinic rays. An actinic ray curable inkjet recording medium, wherein the ink retaining layer is a non-absorbing layer containing at least one of the following compounds (A) or (B):
(A) Acrylic resin obtained by soap-free polymerization (B) Fluorine resin water / oil repellent (2) The compound is a water-soluble fluorine resin water / oil repellent, described in (1) above Actinic ray curable inkjet recording media.
(3) An actinic ray curable ink composition is printed on the non-absorbing ink holding layer of the actinic ray curable ink jet recording medium described in (1) and (2) above by an inkjet method, An actinic ray curable ink jet recording method comprising curing an ink composition.

  The present invention can provide an actinic ray curable ink jet recording medium and a recording method that have high color developability, high definition, and excellent image sharpness.

  The present invention is described in detail below.

  The actinic ray curable ink jet recording medium in the present invention has an ink holding layer on at least one surface of a non-absorbent substrate. The ink retaining layer is a non-absorbing layer that retains the actinic ray curable ink composition printed by the ink jet method on the surface, not the layer that absorbs the actinic radiation curable ink composition. By providing on the material, the actinic ray curable ink composition is retained without being absorbed as a recording medium. As a result, the actinic ray curable ink composition held on the surface of the recording medium is cured by actinic rays and fixed, whereby high color developability is obtained.

The ink holding layer of the present invention is a non-absorbing layer containing at least one of (A) an acrylic resin obtained by soap-free polymerization or (B) a fluorine resin water and oil repellent compound. By providing such an ink holding layer, an actinic ray curable ink composition having a low surface tension can maintain a high contact angle when printed and held on the ink holding layer, thereby obtaining very high image sharpness. be able to. When the ink holding layer does not contain the compound (A) or (B) described above, the image sharpness is lowered. The non-absorbing layer means a layer in which the ink composition is not substantially absorbed into the ink holding layer and the ink composition is held on the ink holding layer. It means that the amount of water absorbed into the layer is 1.0 g / m ² or less on one side. When an undercoat layer exists between the non-absorbent substrate and the ink holding layer, it means that the sum of the water absorption amounts of both the ink holding layer and the undercoat layer is 1.0 g / m ² or less. To do.

  The amount of water absorbed into the ink holding layer in the present invention is obtained by cutting an actinic ray curable ink jet recording medium having an ink holding layer on a non-absorbing substrate into an arbitrary size such as 10 cm × 10 cm, and the like. It can be calculated from the difference in mass between the media after impregnating with ion exchange water for 1 minute and adhering without adsorbing on the surface and back surface of the ink holding layer with the filter paper.

  The amount of the compound (A) or (B) added to the ink holding layer is preferably 20% by mass or more, more preferably 50% by mass or more, based on the total solid content of the ink holding layer.

  The soap-free polymerization used when producing the acrylic resin (A) in the present invention is a low molecular weight substance having a molecular weight of 1000 or less, which is generally used as an emulsifier during the polymerization reaction of a water-insoluble polymer. The emulsion is polymerized by using a water-soluble polymer compound, which will be described later, instead of the surfactant, and is also called a saw press. This water-soluble polymer compound hydrophilizes the water-insoluble polymer as a protective colloid or copolymer component of the water-insoluble polymer. The emulsion polymer obtained by such soap-free polymerization has a higher hydrophobicity of the dry film and can maintain a high contact angle than the emulsion polymer using a surfactant, and high image sharpness can be obtained.

  As the water-soluble polymer compound, an anionic water-soluble polymer compound, a cationic water-soluble polymer compound, and a nonionic water-soluble polymer compound can be used. However, the anion water-soluble polymer compound is excellent in terms of stability during polymerization. Water-soluble polymer compounds and cationic water-soluble polymer compounds are preferred.

  Specific examples of the anionic water-soluble polymer compound that can be used in the present invention include sulfate group-modified polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, sodium carboxymethyl cellulose, sodium polyglutamate, sodium polyaspartate, polylactic acid, sodium polystyrene sulfonate. , Ammonium polystyrene sulfonate, sodium polyacrylate, ammonium polyacrylate, sodium polymethacrylate, ammonium polymethacrylate, and the like. Particularly preferred are sulfonic acid group-modified polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, and carboxymethyl cellulose. These may be used alone or in combination of two or more.

  Specific examples of the cationic water-soluble polymer compound that can be used in the present invention include amino group-modified polyvinyl alcohol, polydiallyldimethylammonium chloride, cationized hydroxyethylcellulose, and the like, and particularly amino group-modified polyvinyl alcohol and polydiallyldimethylammonium. Chloride is preferred. These may be used alone or in combination of two or more.

  Specific examples of the nonionic water-soluble polymer compound that can be used in the present invention include polyvinyl alcohol, polyvinyl pyrrolidone, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, polyethylene oxide and the like, and in particular, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxyethyl cellulose. Is preferred. These may be used alone or in combination of two or more.

  The molecular weight of the water-soluble polymer compound is preferably 5000 or more, more preferably 20000 or more. If the amount used is too small, the dispersion stability of the particles will be poor, and agglomeration of polymer particles after polymerization will occur.On the other hand, if it is too large, the hygroscopicity of the polymer particles will increase. 0.01-1.0 mass part is preferable with respect to 100 mass parts of monomers, and 0.05-0.5 mass part is more preferable.

  The acrylic resin obtained by soap-free polymerization of the compound (A) in the present invention contains alkyl acrylate or alkyl methacrylate as a main component, and these components are 30 to 90 mol%, and What copolymerized 70-10 mol% of the vinyl monomer component which has a functional group is preferable.

  Examples of alkyl groups of alkyl acrylate and alkyl methacrylate include methyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, 2-ethylhexyl group, lauryl group, stearyl group, cyclohexyl group and the like.

  As the vinyl monomer having a functional group copolymerizable with alkyl acrylate or alkyl methacrylate, compounds having a functional group such as a reactive functional group, a self-polymerizable functional group, and a hydrophilic group can be used.

  Specific examples of vinyl monomers include (1) alkali metal salts or alkaline earth metal salts such as acrylic acid, methacrylic acid, itaconic acid and maleic acid, ammonium salts or maleic anhydride, and (2) vinyl sulfone. Acids, styrene sulfonic acids, metal salts such as sodium of these sulfonic acids, ammonium salts, (3) acrylamide, methacrylamide, N-methyl methacrylamide, methylol acrylamide, methylol methacrylamide, ureido vinyl ether, β-ureido isobutyl Vinyl ether, ureidoethyl acrylate, (4) diethylaminoethyl vinyl ether, 2-aminoethyl vinyl ether, 3-aminopropyl vinyl ether, 2-aminobutyl vinyl ether, dimethylaminoethyl methacrylate, Methylaminoethyl vinyl ether, methylolated or quaternized amino group thereof, (5) β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, β-hydroxyvinyl ether , 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl vinyl ether, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monoacrylate, polypropylene glycol monomethacrylate, (6) glycidyl acrylate, glycidyl methacrylate, and the like.

  Furthermore, the acrylic resin obtained by the soap-free used in the present invention may use the following compounds in addition to the above as a copolymerization component. That is, acrylonitrile, styrenes, butyl vinyl ether, maleic acid mono or dialkyl ester, fumaric acid mono or dialkyl ester, itaconic acid mono or dialkyl ester, methyl vinyl ketone, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl pyridine, vinyl pyrrolidone, Examples thereof include, but are not limited to, vinyltrimethoxysilane.

  As polymerization initiators used for soap-free polymerization, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [2- (N-phenylamidino) propane] dihydrochloride, 2, 2'-azobis [2- [N- (4-chlorophenyl) amidine] propane] dihydrochloride, 2,2'-azobis [2- (N-benzylamidino) propane] dihydrochloride, 2,2'-azobis There are [2- (N-allylamidino) propane] dihydrochloride, 2,2′-azobis [2- [N- (2-hydroxyethyl) amidino] propane] dihydrochloride, etc., one or two of these More than one species can be selected and used.

  The fluorine resin water / oil repellent of the compound (B) includes a perfluoropolyether group, a perfluoroalkyl group, etc. that remarkably lowers the surface energy of the solid surface and expresses a high degree of oil repellency / water repellency. A fluororesin is preferred. Specific examples include acrylic monomers containing perfluoroalkyl groups and perfluoropolyether groups, acrylic resins copolymerized with monomers such as alkyl acrylates and alkyl methacrylates, and urethane resins containing perfluoroalkyl groups. These are aqueous emulsions emulsion-polymerized with surfactants, and water-soluble or water-dispersible ones having a hydrophilic group introduced into the molecule. Examples of such a hydrophilic group include a carboxyl group, a hydroxyl group, an amide group or a substituted amide group, and an amino group.

  Typical examples of commercially available fluorine resin water and oil repellents include Asahi Guard AG-E061, AG-E081, AG-E082, AG-E092, AG-E400, AG-E500D, and AG-E060. , Manufactured by AGC Chemicals Company Asahi Glass Co., Ltd. and sold by Meisei Chemical Industry Co., Ltd. Unidyne TG-5521, TG-5601, TG8711, TG-470B, TG-500S, TG-580, TG-581, TG-658, and TG-9901 are sold by Daikin Industries, Ltd.

  Among the compounds (A) and (B) described above, the water-soluble fluororesin water / oil repellent increases the contact angle of the actinic ray curable ink composition of the present invention and further improves the image sharpness of the present invention. It is particularly preferable because it becomes high.

  In addition to the compound (A) or (B) above, the ink retaining layer includes polyvinyl alcohol, gelatin, polyethylene oxide, polyvinyl pyrrolidone, dextran, dextrin, carrageenan, agar, pullulan, water-soluble polyvinyl butyral, hydroxyethyl cellulose, carboxyl It is also possible to use a hydrophilic binder such as methylcellulose alone or in combination of two or more.

In the present invention, when the ink holding layer contains a hydrophilic binder, the ink holding layer contains a hardener so that the water absorption of the ink holding layer is 1.0 g / m ² or less, thereby suppressing the water absorption by the hydrophilic binder. It is preferable to do. The addition amount of the hardener is preferably 0.5 to 10.0% by mass, more preferably 2.0 to 10.0% by mass with respect to the hydrophilic binder.

  In addition, known organic fine particles, inorganic fine particles, antistatic agents, colorants and the like can be appropriately used for the ink holding layer as long as the effects of the present invention are not impaired.

The coating amount of the ink retaining layer is not particularly limited as long as the non-absorbent substrate surface can be completely covered and the water absorption amount can be 1.0 g / m ² or less, but preferably 0.05 to 8 g / m. ² and more preferably 0.05 to 3 g / m ² . When the coating amount of the ink holding layer is increased, the curling property is deteriorated, which is not preferable. When an absorbent substrate is used or an ink holding layer is applied on the ink absorbing layer, in order to obtain the same amount of water absorption as the ink holding layer of the present invention, the substrate surface and the ink absorbing layer must be completely In this case, a very large amount of ink-receiving layer is required, and the curling property is remarkably deteriorated.

  In the present invention, the application method when providing the ink retaining layer is not particularly limited, but a single application and combination of application apparatuses such as a slide bead coater, curtain coater, extrusion coater, air knife coater, rod coater, blade coater, and gravure coater. Can be used.

  Examples of the non-absorbable substrate of the present invention include polyester resins such as polyethylene terephthalate, polypropylene resins, diacetate resins, triacetate resins, polycarbonate resins, polyvinyl chloride, polyimide resins, cellophane, celluloid and other plastic resin films, rubber Actinic ray curable ink compositions such as paper, resin film bonded together, polyolefin resin-coated paper coated with a polyolefin resin layer on both sides of the base paper, resin films that can be shrunk by heat, metals, glass, etc. A substrate that does not absorb water can be used as appropriate. The thickness of these non-absorbent substrates is not particularly limited, and any non-absorbable substrate can be used as long as it can be printed by a printer.

An undercoat layer is preferably provided on the side of the non-absorbent substrate on which the ink holding layer is applied, from the viewpoint of adhesion between the substrate and the ink holding layer and applicability of the ink holding layer. This undercoat layer is applied and dried in advance on the surface of the non-absorbent substrate before the ink retaining layer is applied. This undercoat layer is made of a film-forming polyvinyl alcohol, gelatin, polyethylene oxide, polyvinyl pyrrolidone, dextran, dextrin, carrageenan, agar, pullulan, water-soluble polyvinyl butyral, hydroxyethyl cellulose, carboxymethyl cellulose and other acrylic polymers, and acrylic resins. Mainly contains resin latex such as urethane resin. Adhesion amount of the undercoat layer is preferably ^{10~500mg / m 2, 20~300mg / m} 2 is more preferable. There is no restriction | limiting in particular in the coating method of undercoat layer, A well-known coating method can be used suitably.

  The actinic ray curable ink jet recording medium in the present invention is suitably used for the aforementioned sign & display, signboard, printing application, etc., but those using a transparent PET base material are disclosed in, for example, JP-A-11-10826. Can also be used as a plate-making film for plate making such as intaglio, letterpress and lithographic printing. Further, after ink jet printing, the non-image area can be desensitized and used as a lithographic printing plate precursor. Examples of the treatment liquid used for such a desensitizing treatment are described in JP-A-5-289341, JP-A-7-56349, JP-B-45-29001, JP-B-61-28987, and the like. And a treatment liquid containing colloidal fine particles and a hygroscopic polyol described in JP-B-56-41992. Application of these treatment liquids to the plate surface is a method of hand etching in which absorbent cotton or the like is impregnated with the treatment solution and applied all over the plate surface, a method of applying a certain amount of the treatment solution with a bar coater, For example, a method using an etching converter that is immersed in a stored liquid bath and squeezes excess treatment liquid with a roll pair can be applied.

  When used as a platemaking film, it has a high transmission density and good image sharpness. Therefore, when a printing plate is prepared using the platemaking film and printed on printing paper, the image sharpness is high. A final print is obtained. When used as a lithographic printing plate precursor, a final printed matter with high image sharpness can be obtained when printing on printing paper using this.

  The actinic ray curable ink composition in the present invention includes at least a polymerization initiator, a polymerizable compound, and a colorant, and includes γ rays, β rays, electron beams, visible rays, infrared rays, ultraviolet rays (UV). ) And the like, and the polymerization initiator acts as a catalyst upon irradiation with actinic rays, and the like, and thus has a property of being cured and fixed by a polymerization reaction of the polymerizable compound. Among actinic rays, ultraviolet rays (UV) are preferably used from the viewpoints of reactivity and safety.

  The actinic ray curable ink composition includes a radical polymerization type ink composition comprising a radical polymerization initiator and a radical polymerizable compound, and a cationic polymerization type ink composition comprising a cationic polymerization initiator (photoacid generator) and a cationic polymerizable compound. The actinic ray curable ink compositions of both types can be applied to the present invention alone or in combination.

  As radical polymerization initiators, aromatic ketones, aromatic onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, Known compounds such as a compound having a carbon halogen bond and an alkylamine compound can be used, and these can be used alone or in combination.

Cationic polymerization initiators include B (C ₆ F ₅ ) ₄ salts, PF ₆ salts, AsF ₆ salts, SbF ₆ salts, CF ₃ SO ₃ salts of aromatic onium compounds such as diazonium, ammonium, iodonium, sulfonium, phosphonium, etc. A sulfonated compound that generates sulfonic acid, a halide that generates hydrogen halide, a chemically amplified photoresist such as an iron allene complex, or a known compound used for photocationic polymerization can be used.

  These polymerization initiators in the present invention can be used alone or in combination. These radical polymerization initiators are preferably in the range of 0.01 to 20 parts by mass, more preferably 0.1 to 20 parts by mass, and further preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the polymerizable compound. And contained in an actinic ray curable ink composition.

  The radical polymerizable compound may be any compound as long as it has at least one ethylenically unsaturated bond capable of radical polymerization in the molecule, and monomers, oligomers, polymers, and the like can be used as appropriate. These can be used alone or in combination.

  Specific examples of the radical polymerizable compound include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid and other unsaturated carboxylic acids and their salts, ethylenically unsaturated anhydrides, acrylonitrile, Known radical polymerizable compounds such as styrene, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes may be used.

  The cationically polymerizable compound is not particularly limited as long as it is a compound that initiates a polymerization reaction with an acid generated from a cationic polymerization initiator (photoacid generator) and cures. For example, JP-A-6-9714 discloses a special compound. JP 2001-31892, JP 2001-40068, JP 2001-55507, JP 2001-310938, JP 2001-310937, JP 2001-220526, etc. Known photocationically polymerizable monomers such as epoxy compounds, vinyl ether compounds, and oxetane compounds described in 1) can be used.

  Examples of the epoxy compound include aromatic epoxides, alicyclic epoxides, aliphatic epoxides, and the like. As the aromatic epoxide, a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof and epichlorohydrin are used. Di- or polyglycidyl ethers produced by reaction, for example, di- or polyglycidyl ethers of bisphenol A or its alkylene oxide adducts, di- or polyglycidyl ethers of hydrogenated bisphenol A or its alkylene oxide adducts, and novolaks Type epoxy resin and the like. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  As the alicyclic epoxide, cyclohexene oxide or cyclopentene obtained by epoxidizing a compound having at least one cycloalkane ring such as cyclohexene or cyclopentene ring with an appropriate oxidizing agent such as hydrogen peroxide or peracid. Preference is given to oxide-containing compounds.

  Examples of aliphatic epoxides include dihydric polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof, and typical examples thereof include diglycidyl ether of ethylene glycol, diglycidyl ether of propylene glycol, or 1,6. -Diglycidyl ether of alkylene glycol such as diglycidyl ether of hexanediol, polyglycidyl ether of polyhydric alcohol such as di- or triglycidyl ether of glycerin or its alkylene oxide adduct, diglycidyl of polyethylene glycol or its alkylene oxide adduct Diglycidyl of polyalkylene glycol typified by diglycidyl ether of ether, polypropylene glycol or its alkylene oxide adduct Ether and the like. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  The coloring material in the present invention is not particularly limited, but does not function as a polymerization inhibitor in the polymerization reaction that is a curing reaction, does not reduce the sensitivity of the curing reaction by actinic radiation, has excellent weather resistance, and has excellent color reproducibility. Pigment colorants and oil-soluble dye colorants are preferred, and can be appropriately selected from known colorants. In the present invention, the microencapsulated pigment colorant described in JP-A-2009-227822 can also be used. These colorants can be used alone or in combination, and are preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and still more preferably 100 parts by mass of the polymerizable compound. It is contained in the actinic ray curable ink composition in the range of 0.1 to 10 parts by mass.

  The actinic ray curable ink composition of the present invention has an action such as further improving the sensitivity of the polymerization initiator to actinic radiation, if necessary, in addition to the polymerization initiator, the polymerizable compound, and the coloring material. It may contain a known sensitizer, a polymerization inhibitor for enhancing storage stability, a surfactant, a matting agent, an organic solvent for adjusting viscosity, and the like.

  The actinic ray curable ink jet recording apparatus used in the present invention is not particularly limited, and a commercially available ink jet recording apparatus can be used. However, the effect of the present invention can be remarkably obtained in a high resolution recording apparatus having a resolution exceeding 1200 dpi. The actinic ray curable inkjet recording apparatus used in the present invention preferably has, for example, an ink supply system, a temperature sensor, and an actinic ray 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.

  As an actinic ray source, a mercury lamp, a gas / solid laser, etc., or an ultraviolet light curable ink jet, a mercury lamp, a metal halide lamp, LED (UV-LED), and LD (UV-LD) can be used. . In particular, when an ultraviolet ray source is required, it is preferable from the environmental viewpoint to use UV-LED and UV-LD.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, the content of this invention is not restricted to an Example. In addition, a part represents the mass part of solid content or a substantial component.

Example 1
<Preparation of non-absorbent substrate>
A 1: 1 mixture of hardwood bleached kraft pulp (LBKP) and hardwood bleached sulfite pulp (LBSP) was beaten to 300 ml with Canadian Standard Freeness to prepare a pulp slurry. The sizing agent and alkyl ketene dimer were 0.5% by mass of pulp, 1% by mass of polyacrylamide as a strengthening agent, 1% by mass of cationized starch, 2% by mass of pulp, and polyamide epichlorohydrin resin by 0.1% of pulp. 5% by mass was added and diluted with water to give a 0.2% by mass slurry. This slurry was made with a long paper machine to a basis weight of 170 g / m ² , dried and conditioned to obtain a base paper for the support. A polyethylene resin composition in which 10% by mass of anatase-type titanium dioxide is uniformly dispersed with respect to a low density polyethylene resin having a density of 0.918 g / cm ³ is melted at 320 ° C. on the printed surface side of the base paper produced at a temperature of 200 m. The resin coating layer on the ink holding layer application surface side was provided while being cooled with a cooling roll having a finely roughened surface, which was extruded to a thickness of 30 μm per minute. On the opposite side to melt at similarly 320 ° C. The blend resin composition of the low density polyethylene resin 30 parts of a density 0.962 g / cm 70 parts high density polyethylene resin of ³ and a density 0.918 g / cm ^3, a thickness A resin coating layer was provided while cooling with a cooling roll to 25 μm.

After the high-frequency corona discharge treatment was performed on the surface of the water-resistant support on which the ink retaining layer was applied, the undercoat layer having the following composition was coated and dried so that the gelatin content was 50 mg / m ^2, and the non-absorbing property of Example 1 A substrate was prepared.

<Undercoat layer>
Lime-processed gelatin 100 parts Sulfosuccinic acid 2-ethylhexyl ester salt 2 parts Chrome alum 10 parts

The ink holding layer coating solution 1 having the following composition is coated on the non-absorbent substrate with a slide bead coating device so that the solid content is 0.8 g / m ² , cooled at 5 ° C. for 30 seconds, and then 40 ° C. and 10% RH. The actinic ray curable ink jet recording medium of Example 1 was produced by drying to the end of drying.

<Ink holding layer coating solution 1>
Soap-free polymerized acrylic resin (manufactured by DIC Corporation, SFC-571) 60 parts alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 40 parts epoxy cross-linking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX-521) It adjusted with water so that 3 part solid content concentration might be 5 mass%.

(Example 2)
An actinic ray curable inkjet recording medium of Example 2 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 2.

<Ink holding layer coating liquid 2>
Soap-free polymerized acrylic resin (manufactured by Etec Co., Ltd., AE986E) 60 parts Alkali-treated gelatin (Nitta Gelatin Co., Ltd.) 40 parts Epoxy crosslinking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX-521) 3 parts It adjusted with water so that solid content concentration might be 5 mass%.

(Example 3)
An actinic ray curable inkjet recording medium of Example 3 was prepared in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 3.

<Ink holding layer coating liquid 3>
Fluorine resin water and oil repellent (emulsified with cationic surfactant. AGE082 manufactured by Asahi Glass Co., Ltd.)
60 parts alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 40 parts epoxy cross-linking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX-521) 3 parts Adjusted with water so that the solid content concentration is 5% by mass .

Example 4
An actinic ray curable ink jet recording medium of Example 4 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 4.

<Ink holding layer coating solution 4>
Fluorine-based resin water and oil repellent (water-soluble type, manufactured by Asahi Glass Co., Ltd., AGE060) 60 parts alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 40 parts epoxy-based crosslinking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX -521) Adjusted with water so that 3 parts solids concentration was 5% by weight.

(Example 5)
The actinic ray curable inkjet recording medium of Example 5 was produced in the same manner as in Example 4 except that the coating amount of the ink retaining layer in Example 4 was changed to 2.0 g / m ² .

(Example 6)
The actinic ray curable inkjet recording medium of Example 6 was changed in the same manner as in Example 4 except that the non-absorbent substrate of Example 4 was changed to a 150 μm thick white polyethylene terephthalate film subjected to easy adhesion treatment. Produced.

(Example 7)
The actinic ray curable ink jet recording medium of Example 7 was produced in the same manner as in Example 4 except that the non-absorbable substrate of Example 4 was changed to a 200 μm-thick PVC film subjected to easy adhesion treatment. .

(Example 8)
The actinic ray curable inkjet recording medium of Example 8 was changed in the same manner as in Example 1 except that the non-absorbable substrate of Example 1 was changed to a transparent polyethylene terephthalate film having a thickness of 100 μm subjected to easy adhesion treatment. Produced.

Example 9
The actinic ray curable inkjet recording medium of Example 9 was changed in the same manner as in Example 4 except that the non-absorbent substrate of Example 4 was changed to a transparent polyethylene terephthalate film having a thickness of 100 μm subjected to easy adhesion treatment. Produced.

(Example 10)
An actinic ray curable inkjet recording medium of Example 10 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 5.

<Ink holding layer coating solution 5>
Fluorine-based resin water and oil repellent (water-soluble type, manufactured by Asahi Glass Co., Ltd., AGE060) 40 parts alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 60 parts epoxy-based crosslinking agent (manufactured by Nagase Kasei Co., Ltd., Denacor EX -521) Adjusted with water so that 3 parts solids concentration was 5% by weight.

(Comparative Example 1)
The non-absorbing substrate of Example 1 was used as the actinic ray curable inkjet recording medium of Comparative Example 1 as it was.

(Comparative Example 2)
An actinic ray curable inkjet recording medium of Comparative Example 2 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 6.

<Ink holding layer coating liquid 6>
Alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 100 parts epoxy cross-linking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX-521) 8 parts It was adjusted with water so that the solid content concentration was 5% by mass.

(Comparative Example 3)
An actinic ray curable inkjet recording medium of Comparative Example 3 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 7.

<Ink holding layer coating solution 7>
Acrylic resin (emulsified with anionic surfactant. AE610H, manufactured by Etec Co., Ltd.)
60 parts alkali-treated gelatin (manufactured by Nitta Gelatin Co., Ltd.) 40 parts epoxy cross-linking agent (manufactured by Nagase Kasei Co., Ltd., Denacol EX-521) 3 parts Adjusted with water so that the solid content concentration is 5% by mass .

(Comparative Example 4)
An actinic ray curable inkjet recording medium of Comparative Example 4 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 1 of Example 1 was changed to the following ink holding layer coating liquid 8.

<Ink holding layer coating liquid 8>
Soap-free polymerized urethane resin (DIC Corporation, AP20) 60 parts Alkali-treated gelatin (Nitta Gelatin Co., Ltd.) 40 parts Epoxy crosslinking agent (Nagase Kasei Co., Ltd., Denacol EX-521) 3 parts It adjusted with water so that solid content concentration might be 5 mass%.

(Comparative Example 5)
The following ink absorbing layer coating solution was applied to the non-absorbing substrate of Example 1 with a slide bead coating device so that the solid content was 3.0 g / m ² , cooled at 5 ° C. for 30 seconds, and then 40 ° C. and 10% RH. And dried to the end of drying. Then, the following ink holding layer coating solution 9 was applied onto the ink absorbing layer with a gravure coating device so that the solid content was 60 mg / m ² , dried by spraying heated air at 50 ° C., and actinic ray curing of Comparative Example 5 Type ink jet recording media were prepared.

<Pigment dispersion>
After adding 3 parts of dimethyldiallyl aluminum chloride homopolymer (molecular weight: 9000) and 100 parts of vapor phase method silica (average primary particle diameter 7 nm, specific surface area 300 m ² / g) to water to prepare a preliminary dispersion, using a high-pressure homogenizer The gas phase method silica dispersion 1 having a solid content concentration of 20% by mass was prepared. In addition, the average secondary particle diameter of the vapor phase method silica measured by a laser diffraction / scattering type particle size distribution analyzer was 80 nm.

<Ink absorbing layer coating solution>
Pigment dispersion 103 parts boric acid 5 parts polyvinyl alcohol 23 parts (saponification degree 88%, average polymerization degree 3500)
It adjusted with water so that solid content concentration might be 12 mass%.

<Ink holding layer coating liquid 9>
Water 92.2 parts Denatured ethanol 5 parts Soap-free polymerized acrylic resin (manufactured by DIC Corporation, SFC-571) 2.8 parts

(Comparative Example 6)
The actinic ray curable inkjet recording medium of Comparative Example 6 was produced in the same manner as Comparative Example 5 except that the solid content of the ink absorbing layer coating liquid of Comparative Example 5 was changed to 20 g / m ² .

(Comparative Example 7)
The activity of Comparative Example 7 is the same as Example 1 except that the non-absorbent substrate of Example 1 is changed to a base paper (absorbent substrate) before coating the polyethylene resin composition of Example 1. A light curable ink jet recording medium was prepared.

(Comparative Example 8)
An actinic ray curable inkjet recording medium of Comparative Example 8 was produced in the same manner as in Example 1 except that the ink holding layer coating liquid 4 of Example 9 was changed to the ink holding layer coating liquid 7.

<Water absorption amount of ink holding layer>
Each of the actinic ray curable ink jet recording media produced as described above is cut to a size of 10 cm × 10 cm, impregnated with 20 ° C. ion exchange water for 1 minute, and adhered to the ink holding layer surface and back surface without being absorbed. The water absorption amount of the ink holding layer was calculated from the media mass difference after the moisture was wiped with filter paper and before the impregnation. In Comparative Example 7, since a water-absorbing substrate was used, measurement was performed by excluding the amount of water absorption from the opposite surface by laminating the opposite surface of the ink holding layer surface in advance with an adhesive tape. The results are shown in Table 1.

  For each of the actinic ray curable ink jet recording media produced as described above, an image was obtained at a high resolution of 1440 dpi using a UV ink jet printer (LEC-330, manufactured by Roland DG Co., Ltd.) using an ultraviolet curable ink composition. Was printed and cured by ultraviolet irradiation, and the following items were evaluated.

<Color development>
Using the printer, the color developability of a solid image printed and cured with red, blue, green and black inks was visually evaluated according to the following criteria. The results are shown in Table 1.
○: Very high color developability.
Δ: Color development is slightly inferior to ○.
X: Level at which color developability is further inferior to Δ.

<Image sharpness>
Using the printer, the sharpness of 2, 4, 6, 8 point characters and 0.1 mm line & space images printed and cured with red, blue, green and black inks was visually evaluated according to the following criteria. . The results are shown in Table 1.
(Double-circle): The sharpness of a character and an image is very high. Obviously better than ○.
○: Sharpness of characters and images is high.
Δ: Characters and images are slightly inferior to ○.
X: The sharpness of characters and images is further inferior to Δ.

  From the results in Table 1, it can be seen that according to the present invention, an actinic ray curable ink jet recording medium having high color developability, high definition and excellent image sharpness can be obtained.

  The same solid, character, line & space images were printed on the recording media of Examples 8 and 9 and Comparative Example 8 using the printer, and cured to obtain a printing plate precursor film. Using this printing plate precursor film, the PS plate (Fuji Film Co., Ltd., Advanced VS) was closely exposed and developed with a processor (Fuji Film Co., Ltd., PS-1310VIIB) with a developer (Fuji Film Co., Ltd., A lithographic printing plate was prepared by developing using DP-7). After that, the printing machine uses HAMADA DU34II (Hamada Printing Machine Co., Ltd. offset printing machine), the ink is New Champion F gloss ink 85N (DIC Corporation), and the dampening liquid is SLM-OD (Mitsubishi Paper Co., Ltd.). Use a 3% by weight aqueous solution of (humidifier) and wipe off the entire plate surface using a 25% by weight aqueous solution of SLM-OD30 (Mitsubishi Paper Co., Ltd. etchant) before starting printing. (Mitsubishi Paper Co., Ltd., pearl coat) was printed. As a result, in Examples 8 and 9, final printed matter having higher image sharpness than Comparative Example 8 was obtained.

Claims (3)

For recording in which an ink holding layer is applied on at least one surface of a non-absorbent substrate, which is used in a recording method in which an ink composition is used for printing using an actinic ray curable ink composition and then the ink composition is cured by actinic rays. An actinic ray curable ink jet recording medium, wherein the ink holding layer is a non-absorbing layer containing at least one of the following compounds (A) or (B).
(A) Acrylic resin by soap-free polymerization (B) Fluorine resin Water and oil repellent   The actinic ray curable ink jet recording medium according to claim 1, wherein the compound is a water-soluble fluororesin water- and oil-repellent agent.   The actinic ray curable ink composition is printed on the non-absorbing ink holding layer of the actinic ray curable ink jet recording medium according to claim 1 or 2 by an ink jet method, and then the ink composition is applied with actinic rays. An actinic ray curable inkjet recording method comprising curing.