JPWO2006082733A1 - Ink jet recording method using active energy ray curable ink jet ink and active energy ray curable ink jet recording apparatus - Google Patents

Abstract

An ink jet recording method comprising a step of performing pretreatment on a surface of a substrate to form a pretreatment layer and a step of recording by discharging an active energy ray-curable ink jet ink onto the pretreatment layer. The pretreatment agent is a polymer latex. Using an active energy ray-curable inkjet ink, a recording method for an active energy ray-curable inkjet ink capable of printing with high productivity, low cost, no bleeding, high image quality, and excellent substrate adhesion, and used therein A recording device can be provided.

Description

  The present invention relates to a method for recording an active energy ray-curable inkjet ink and an active energy ray-curable inkjet recording apparatus used therefor.

  In recent years, inkjet recording methods can be used to create images easily and inexpensively, and thus have been applied to various printing fields such as photographs, various printing, marking, and special printing such as color filters. A recording device that emits and controls fine dots, ink with improved color gamut, durability, and ejection suitability, and special paper that dramatically improves ink absorptivity, color development, surface gloss, etc. It is also possible to obtain image quality comparable to silver halide photography. That is, the image quality improvement of today's inkjet recording system is achieved only when all of the recording apparatus, ink, and special paper are available.

  On the other hand, soft packaging is printed by a gravure printing method or a flexographic printing method. Gravure printing and flexographic printing are progressing at low cost and short delivery due to innovations in manufacturing methods. However, it takes a lot of time and cost to create a printing plate, and it takes time to stabilize the density after starting printing. Therefore, in the case of a small amount of sample (prototype, exhibition, limited sale product, etc.), a large amount of loss occurs and the unit price becomes high.

  Recently, some samples can be made on soft packaging film by wet electrophotographic method, but it takes time to adjust the level at start-up, and there is a problem with durability of printed images. It cannot be handled.

  Inkjet recording systems for flexible packaging are generally recorded in black or white after packaging, with the date of manufacture, expiration date, etc., but images such as letters, design drawings and photographs are directly recorded. Recording is not common.

  Also, in recent packaging, various ideas have been devised, such as using mat packaging materials, making the mat base material a glossy surface, or vice versa, in order to bring out the concept and features of the product. . Furthermore, the required quality has been increasing year by year, such as high image quality and a sense of incongruity in touch.

  Therefore, a method of recording an image on a film substrate by an inkjet method using UV (ultraviolet) curable ink has been studied. In general, there are various types of film substrates, and the wettability varies depending on the raw materials, additives, and surface conditions of the substrates. In normal printing (mainly gravure printing), by changing the ink and printing conditions depending on the base material, or after pretreatment such as corona treatment by the base material manufacturer, it is used up within a certain period, or by corona treatment immediately before It corresponds.

  However, when using an inkjet, changing the ink for each base material greatly impairs the ease and convenience of the original inkjet, and using the base material within a certain period of time is premised on mass printing. Even if there is no problem with gravure or the like, there will be a lot of loss in an inkjet designed for a small variety of products. In addition, it is not practical to use a pretreatment such as a corona treatment of a conventional printed matter because the productivity of the conventional printing press is remarkably lowered.

Various improvement means have been studied for the above problems, and for example, UV curable undercoat layers (see Patent Documents 1, 2, and 4), corona treatment, and plasma treatment (see Patent Document 3) are disclosed. . However, these proposed recording methods have not yet sufficiently improved the above problems.
JP 2002-530229 A (Claims) JP 2003-211161 A (Claims) JP 2003-237217 A (Claims) JP 2004-59810 A (Claims)

  The present invention has been made in view of the above problems, and its purpose is to achieve high productivity, low cost, no blur, high image quality and substrate adhesion using an active energy ray-curable inkjet ink. It is an object of the present invention to provide an active energy ray curable inkjet ink recording method capable of excellent printing and an active energy ray curable inkjet ink recording apparatus used therefor.

The above object of the present invention is achieved by the following configurations.
1. An ink jet recording method comprising a step of performing pretreatment on a surface of a substrate to form a pretreatment layer and a step of recording by discharging an active energy ray-curable ink jet ink onto the pretreatment layer. An inkjet recording method using an active energy ray-curable inkjet ink, wherein the pretreatment agent is a polymer latex.
2. 2. The ink jet recording method using an active energy ray-curable ink jet ink according to 1, wherein the polymer latex contains a polymer compound having a cationic polymerization reactive group.
3. 3. The inkjet recording method using the active energy ray-curable inkjet ink according to 1 or 2, wherein the active energy ray-curable inkjet ink contains a cationic polymerizable compound.
4). 4. The active energy ray-curable inkjet ink according to any one of 1 to 3, wherein the cationic polymerizable compound is at least one selected from an oxetane ring-containing compound, an oxirane group-containing compound, and a vinyl ether compound. Inkjet recording method.
5. The inkjet recording method using the active energy ray-curable inkjet ink according to any one of 1 to 4, wherein the active energy ray-curable inkjet ink contains a cationic photopolymerization initiator.
6). The inkjet recording method using an active energy ray-curable inkjet ink according to any one of 1 to 5, wherein the active energy ray-curable inkjet ink contains a pigment and a pigment dispersant.
7). 7. The inkjet recording method using an active energy ray-curable inkjet ink according to 6, wherein the pigment is pigment particles having an average particle size of 10 to 150 nm.
8). 8. The inkjet recording method using an active energy ray-curable inkjet ink according to any one of 1 to 7, wherein the active energy ray-curable inkjet ink has a viscosity at 25 ° C. of 5 to 50 mPa · s.
9. The ink content recording method according to any one of 1 to 8, wherein the water content of the pretreatment layer is 0.01 to 5% by mass.
10. 10. The inkjet recording method using an active energy ray-curable inkjet ink according to any one of 1 to 9, wherein the film thickness of the pretreatment layer is 0.001 μm to 2 μm.
11. The step of performing pretreatment using the pretreatment agent to form a pretreatment layer and the step of performing recording by discharging an active energy ray-curable inkjet ink onto the pretreatment layer are performed continuously. 11. An inkjet recording method using the active energy ray-curable inkjet ink according to any one of 1 to 10, which is characterized.
12 The active energy ray curing according to any one of 1 to 11, further comprising a step of heating the substrate after a step of performing a pretreatment using the pretreatment agent to form a pretreatment layer. Ink-jet recording method using an ink jet ink.
13. An active energy ray-curable inkjet recording apparatus, which is used in the inkjet recording method using the active energy ray-curable inkjet ink according to any one of 13.1 to 12.

  ADVANTAGE OF THE INVENTION According to this invention, the recording of the active energy ray hardening-type inkjet ink which can perform printing with high productivity, low cost, no bleeding, high image quality, and excellent substrate adhesion using the active energy ray-curable ink-jet ink. It is possible to provide a method and an active energy ray-curable inkjet ink recording apparatus used therefor.

The recording method of the active energy ray-curable inkjet ink of the present invention (hereinafter also simply referred to as inkjet ink or ink) includes a step of forming a pretreatment layer by performing pretreatment on the surface of a substrate using a pretreatment agent, and An inkjet recording method comprising a step of recording by discharging an active energy ray-curable inkjet ink onto the pretreatment layer, wherein the pretreatment agent is a polymer latex.
It has been found that, by adopting the above configuration, it is possible to realize a recording method of an active energy ray-curable inkjet ink capable of performing printing with no image blur and high image quality and excellent substrate adhesion.

  Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

  In the recording method of the active energy ray-curable inkjet ink of the present invention, as described above, the substrate surface is pretreated using a polymer latex as a pretreatment agent on the substrate (recording medium) surface.

  As the method used for this pretreatment, for example, a method using a coating process such as spray coating, roll coating, gravure coating, air knife coating, extrusion coating, curtain coating, wire bar coating, or felt coating, or an inkjet method is used. However, the ink jet method is preferred in the present invention.

  In the ink jet method, the pretreatment layer can be applied only to the portion where the active energy ray-curable ink jet ink is discharged.

  Polymer latex is a dispersion in which a polymer compound (polymer) is dispersed in a solvent. Styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, polyisoprene, polybutadiene, polyurethane, polyacrylic acid, polychlorinated A known polymer latex in which a polymer compound (polymer) such as vinyl is dispersed in water with an activator, a protective colloid or the like can be preferably used.

In the present invention, the polymer latex preferably contains a polymer compound (polymer) having a cationic polymerization reactive group.
The cationic polymerization reactive group is a group capable of reacting with a cationic polymerizable active species, and examples thereof include groups having an ether bond such as a hydroxyl group, a carboxyl group, an amino group, and an epoxy group, and these are preferably used.

  Specifically, JP-A-5-39324, JP-A-5-93071, JP-A-5-148796, JP-A-5-247181, JP-A-6-92047, JP-A-6-179707, JP-A-6-16776. No. -258771, No. 7-26170, No. 7-28181, No. 7-138304, No. 8-106142, No. 2000-63406, No. 2002-144707, No. 2003-2003. Those described in each publication of No. 246821 can be used.

Furthermore, commercially available polymer latexes described below are also used. SB (styrene butadiene) latex 0561, 0589, 0602, 2108, 0533, 0545, 0548, 0568, 0569, 0573, 0597C, AE (acrylic emulsion) AE116, AE119, AE120, AE121, AE125, AE134, AE137, AE140, AE173, AE200, AE311, AE318, AE337, AE343, AE362, AE373, AE379, AE315, AE517, AE604, AE610, AE815, AE866, AE945, AE950, AE986A (above JSR A, PS) (ROY) (manufactured by Showa Polymer Co., Ltd.), styrene / butadiene latex (Nipol LX407AS series, Nipol LX40) F series, Nipol LX407G series, Nipol LX407H series, Nipol LX407K series, Nipol LX407S series, Nipol 2518FS series, SB LATEX, Nipol
2518GL, Nipol LX603, Nipol LX110, Nipol LX112), polybutadiene and low styrene butadiene series (Nipol LX112A2, Nipol LX111H, Nipol LX111NF, Nipol LX111K, Nipol C4850A), acrylonitrile butadiene 15p, Ni71ol 61p , Nipol 1571C, Nipol 1571CL, Nipol LX517A, Nipol 1577, Nipol LX511A, Nipol LX513), acrylate latex (Nipol LX811H, Nipol LX814, Nipol LX851C, Nipol LX851L, Nipol LX85L) 852, Nipol LX854E, Nipol LX855EX1, Nipol LX857X2, Nipol LX874), Soap Free Latex (Nipol SX1105, Nipol SX1503, Nipol SX1706) (manufactured by Nippon Zeon Co., Ltd.), Yodosol (acrylic resin emulsion, acrylic resin emulsion, acrylic resin emulsion) Emulsions (epoxy resin emulsions) (Nippon NS Co., Ltd.), KATHONLXL, KATHONLXL, KORDEKRMMLX (Rohm & Haas).

  In the case of using an inkjet method as a pretreatment method for the substrate surface, the viscosity of the polymer latex is preferably 10 mPa · s or less at 55 ° C.

  Furthermore, in order to improve the drying property of the polymer latex, an extremely small amount of an organic solvent may be added. In this case, it is effective to add the cured film in such a range that the solvent resistance and VOC do not occur, and the amount is 0.1 to 5% by mass, preferably 0.1 to 3% by mass.

  The pretreatment film is formed on the substrate by the pretreatment using the above polymer latex, but the active energy ray curable inkjet ink is ejected from the viewpoint of preventing image quality deterioration due to bleeding of the active energy ray curable inkjet ink. Before being done, it is preferable that the water content is 0.01 to 5% by mass.

  Therefore, in the present invention, it is preferable to provide, for example, a heat drying step between the step of forming the pretreatment layer with the polymer latex and the step of discharging the active energy ray-curable inkjet ink.

  Although the film thickness of the pretreatment layer formed of the polymer latex depends on the type of substrate, it is more than 0.001 μm, preferably 2 μm or less, more preferably 0.01 to 1 μm.

  Next, the form of the ink jet recording method (image forming method) in the present invention will be described, but the present invention is not limited to this.

<< Inkjet image forming method-No. 1 >>
-Polymer latex coating process-1: roll coating-Polymer latex drying process-1: roll heating-Inkjet ink ejection process: Common << Inkjet image forming method-No. 2 >>
Polymer latex coating process-2: Inkjet method Polymer latex drying process-2: Infrared heating Inkjet ink ejection process: Common << Inkjet image forming method-No. 3 >>
-Polymer latex coating process -3: Immersion coating-Polymer latex drying process -3: Microwave heating-Inkjet ink ejection process: common Next, details of the active energy ray-curable inkjet ink according to the present invention will be described.

  The ink according to the present invention is an active energy ray curable ink, but is preferably an ink containing a cationic polymerization compound. Examples of the cationic polymerization compound include oxetane ring-containing compounds, oxirane group-containing compounds, and vinyl ethers. It is preferably at least one selected from compounds.

  The oxirane group-containing compound according to the present invention is a compound having one or more oxirane rings represented by the following formula in the molecule, and usually used as an epoxy resin is any monomer, oligomer or polymer. Is possible.

  Specific examples include conventionally known aromatic epoxides, alicyclic epoxides, and aliphatic epoxides. Hereinafter, the epoxide means a monomer or an oligomer thereof. These compounds may be used alone or in combination of two or more as required.

  A preferable aromatic epoxide is a di- or polyglycidyl ether produced by the reaction of a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof and epichlorohydrin, such as bisphenol A or an alkylene thereof. Examples thereof include di- or polyglycidyl ethers of oxide adducts, di- or polyglycidyl ethers of hydrogenated bisphenol A or alkylene oxide adducts thereof, and novolak-type epoxy resins. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  Examples of the alicyclic epoxide include cyclohexene oxide 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. Cyclopentene oxide-containing compounds are preferred, and specific examples include, for example, manufactured by Daicel Chemical Industries, Celoxide 2021, Celoxide 2021A, Celoxide 2021P, Celoxide 2080, Celoxide 3000, Celoxide 2000, Epolide GT301, Epolide GT302, Epolide GT401, Epolido GT403, EHPE-3150, EHPEL3150CE, manufactured by Union Carbide, UVR-6105, UVR-6110, UVR-6128, UVR-6 00, UVR-6216, UVR-6000, and the like.

  Preferred aliphatic epoxides include di- or 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 Diglycidyl ether of alkylene glycol such as diglycidyl ether of 1,6-hexanediol, polyglycidyl ether of polyhydric alcohol such as di- or triglycidyl ether of glycerin or its alkylene oxide adduct, polyethylene glycol or its alkylene oxide adduct Of polyalkylene glycols such as diglycidyl ether, polypropylene glycol or diglycidyl ether of its alkylene oxide adduct Glycidyl ether, and the like. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  In addition to these compounds, monoglycidyl ethers of higher aliphatic alcohols and phenols, monoglycidyl ethers of cresol, and the like can also be used. Among these epoxides, in view of fast curability, aromatic epoxides and alicyclic epoxides are preferable, and alicyclic epoxides are particularly preferable.

  The oxirane group-containing compound is blended in the ink in an amount of 10 to 50% by mass, preferably 30 to 50% by mass, from the standpoint of durability as a printed matter and ejection properties.

  Examples of the oxetane ring-containing compound according to the present invention include compounds having one or more oxetane rings in the molecule.

  Examples of the compound having one oxetane ring in the molecule include compounds represented by the following general formula (1).

In the general formula (1), Z is an oxygen atom or a sulfur atom, R ¹ is a hydrogen atom, a fluorine atom, a methyl group, an ethyl group, a propyl group, a butyl group or the like, an alkyl group having 1 to 6 carbon atoms, or a carbon number 1 to 6 fluoroalkyl groups, allyl groups, aryl groups, furyl groups or thienyl groups, R ² is an alkyl group having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group or butyl group, 1- C1-C6 alkenyl such as propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-butenyl group, 2-butenyl group or 3-butenyl group Group, phenyl group, benzyl group, fluorobenzyl group, methoxybenzyl group or phenoxyethyl group, aryl group, propylcarbonyl group, butylcarbonyl group or pentylcarbo An alkylcarbonyl group having 1 to 6 carbon atoms such as an nyl group, an alkoxycarbonyl group having 1 to 6 carbon atoms such as an ethoxycarbonyl group, a propoxycarbonyl group or a butoxycarbonyl group, an ethoxycarbamoyl group, a propylcarbamoyl group or a butylpentylcarbamoyl group Represents an alkoxycarbamoyl group having 1 to 6 carbon atoms such as a group;

As the oxetane ring-containing compound according to the present invention, in the general formula (1), R ¹ is a lower alkyl group, particularly an ethyl group, R ² is a butyl group, a phenyl group or a benzyl group, and Z is an oxygen atom. preferable.

  Examples of the compound having two or more oxetane rings in the molecule include compounds represented by the following general formulas (2) to (8).

In the general formula (2), m represents 2, 3 or 4, Z is an oxygen atom or sulfur atom, R ³ is a hydrogen atom, a fluorine atom, a methyl group, an ethyl group, a propyl group, a butyl group or the like. ˜6 alkyl group, phenyl group, fluoroalkyl group having 1 to 6 carbon atoms, allyl group, aryl group or furyl group, R ⁴ is, for example, one having 1 to 12 carbon atoms represented by the general formula (3) Linear or branched alkylene groups, linear or branched poly (alkyleneoxy) groups,

[Wherein R ⁵ represents a lower alkyl group such as a methyl group, an ethyl group or a propyl group. Or a polyvalent group selected from the group consisting of the following general formulas (4), (5) and (6).

In the general formula (4), n is 0 or an integer of 1 to 2000, R ⁶ is an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group and the following general formula (7) Represents a group selected from the group consisting of

[Wherein j is 0 or an integer of 1 to 100, R ⁸ is an alkyl having 1 to 10 carbon atoms, R ⁷ is a C 1 to C 10 such as methyl, ethyl, propyl or butyl group. Represents an alkyl group. ]

In the general formula (5), R ⁹ is a hydrogen atom, a methyl group, an ethyl group, a propyl group or a butyl group, such as an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, A nitro group, a cyano group, a mercapto group, a lower alkyl carboxylate group or a carboxyl group is represented.

In the general formula (6), R ¹⁰ represents an oxygen atom, a sulfur atom, NH, SO, SO ₂ , CH ₂ , C (CH ₃ ) ₂ or C (CF ₃ ) ₂ .

As the oxetane ring-containing compound according to the present invention, in the above general formula (2), R ³ is a lower alkyl group, particularly an ethyl group, R ⁴ is a group in which R ⁹ in the general formula (5) is a hydrogen atom, hexa In the methylene group, general formula (3), it is preferable that R ⁵ is an ethyl group, R ⁷ and R ⁸ are each a methyl group, and Z is an oxygen atom.

In the general formula (8), r is an integer of 25 to 200, R ¹¹ is an alkyl group or a trialkylsilyl group having 1 to 4 carbon atoms.

  In the present invention, the cationically polymerizable ink may be a combination of two or more compounds having one or more oxetane rings in the molecule.

  The oxetane ring-containing compound is blended in the ink in an amount of 50 to 90% by mass, preferably 50 to 70% by mass, from the viewpoint of durability as a printed matter and ejection properties.

  Examples of the vinyl ether compound contained in the ink according to the present invention include ethylene glycol divinyl ether, ethylene glycol monovinyl ether, diethylene glycol divinyl ether, triethylene glycol monovinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, and dipropylene glycol divinyl ether. , Butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, hydroxyethyl monovinyl ether, hydroxynonyl monovinyl ether, trimethylolpropane trivinyl ether, and other di- or trivinyl ether compounds, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether , Kutadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl ether-o-propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether, octadecyl vinyl ether, etc. And monovinyl ether compounds.

  Of these vinyl ether compounds, in consideration of curability, adhesion, and surface hardness, divinyl ether compounds or trivinyl ether compounds are preferable, and divinyl ether compounds are particularly preferable.

  In the present invention, one of the above vinyl ether compounds may be used alone, or two or more thereof may be used in appropriate combination.

  The vinyl ether compound is an optional compounding component, and the viscosity required for the ink-jet ink can be reduced by compounding. Also, the curing rate can be improved. The vinyl ether compound is preferably blended in an amount of 0 to 40% by mass, preferably 0 to 20% by mass, in a liquid component composed of an oxirane group-containing compound and an oxetane ring-containing compound.

  The ink according to the present invention preferably contains a cationic photopolymerization initiator together with the cationically polymerizable compound.

  Examples of the cationic photopolymerization initiator that can be used in the present invention include arylsulfonium salt derivatives (for example, Cyracure UVI-6990, Cyracure UVI-6974, manufactured by Union Carbide, and Adekaoptomer SP-150, manufactured by Asahi Denka Kogyo Co., Ltd. , Adeka optomer SP-152, Adeka optomer SP-170, Adeka optomer SP-172, etc.), Allyl iodonium salt derivatives (such as RP-2074 manufactured by Rhodia), Allen-ion complex derivatives (such as Ciba Geigy) Irgacure 261 manufactured by the company), diazonium salt derivatives, triazine-based initiators and other halides such as halides.

  The cationic photopolymerization initiator is preferably contained in a ratio of 0.2 to 20 parts by mass with respect to 100 parts by mass of the compound having an alicyclic epoxy group in the ink. When the content of the cationic photopolymerization initiator is less than 0.2 parts by mass, it becomes difficult to obtain a cured product, and even if the content exceeds 20 parts by mass, a further effect of improving curability cannot be expected. These cationic photopolymerization initiators can be used alone or in combination of two or more.

  In the ink according to the present invention, a photopolymerization accelerator can be used, and examples thereof include anthracene and anthracene derivatives (for example, Adekaoptomer SP-100 manufactured by Asahi Denka Kogyo Co., Ltd.). These photopolymerization accelerators can be used alone or in combination.

  The ink according to the present invention preferably contains a pigment and a pigment dispersant as a coloring material.

  Examples of the pigment that can be used in the ink according to the present invention include achromatic inorganic pigments such as carbon black, titanium oxide, and calcium carbonate, or chromatic organic pigments.

  Examples of organic pigments include, for example, insoluble azo pigments such as toluidine red, toluidine maroon, Hansa yellow, benzidine yellow, and pyrazolone red, soluble azo pigments such as lithol red, helio bordeaux, pigment scarlet, and permanent red 2B, alizarin, and indanthrone. , Derivatives from vat dyes such as thioindigo maroon, phthalocyanine organic pigments such as phthalocyanine blue and phthalocyanine green, quinacridone organic pigments such as quinacridone red and quinacridone magenta, perylene organic pigments such as perylene red and perylene scarlet, Isoindolinone organic pigments such as indolinone yellow and isoindolinone orange, and pyranthrone systems such as pyranthrone red and pyranthrone orange Pigments, thioindigo organic pigments, condensed azo organic pigments, benzimidazolone organic pigments, quinophthalone organic pigments such as quinophthalone yellow, isoindoline organic pigments such as isoindoline yellow, and other pigments such as flavanthrone yellow, acyl Examples include amide yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianslaquinonyl red, and dioxazine violet.

Moreover, when an organic pigment is illustrated by a color index (CI) number,
C. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 109, 110, 117, 125, 128, 129, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 185
C. I. Pigment Orange 16, 36, 43, 51, 55, 59, 61
C. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 177, 180, 192, 202, 206, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240
C. I. Pigment Violet 19, 23, 29, 30, 37, 40, 50
C. I. Pigment Blue 15, 15: 1, 15: 3, 15: 4, 15: 6, 22, 60, 64
C. I. Pigment Green 7, 36
C. I. Pigment brown 23, 25, 26, and the like.

  Among the above pigments, quinacridone organic pigments, phthalocyanine organic pigments, benzimidazolone organic pigments, isoindolinone organic pigments, condensed azo organic pigments, quinophthalone organic pigments, isoindoline organic pigments, etc. are light-resistant. Is preferable because it is excellent. The organic pigment is preferably a pigment having an average particle diameter of 10 to 150 nm as measured by laser scattering.

  When the average particle diameter of the pigment is less than 10 nm, the light resistance is lowered due to the small particle diameter, and when it exceeds 150 nm, it is difficult to maintain stable dispersion, and the pigment is likely to precipitate.

  The so-called dispersion treatment of the organic pigment can be performed by the following method. That is, a mixture composed of at least three components of an organic pigment, a water-soluble inorganic salt of 3 mass times or more of the organic pigment, and a water-soluble solvent is made into a clay-like mixture and finely kneaded with a kneader or the like. Put in water and stir with a high speed mixer to make a slurry. Next, the slurry-like mixture is repeatedly filtered and washed with water to remove the water-soluble inorganic salt and the water-soluble solvent. In the miniaturization step, a resin, a pigment dispersant and the like may be added. Examples of the water-soluble inorganic salt include sodium chloride and potassium chloride. These inorganic salts are preferably used in the range of 3 to 20 times the mass of the organic pigment. When the amount of the inorganic salt is less than 3 times by mass, pigment particles having a desired size cannot be obtained. On the other hand, when the amount is more than 20 times by mass, the cleaning process in the subsequent step is enormous, and the substantial processing amount of the organic pigment is reduced.

  A water-soluble solvent is used to create an appropriate clay state of an organic pigment and a water-soluble inorganic salt used as a crushing aid, and to perform sufficient crushing efficiently. Although not limited, a high boiling point solvent having a boiling point of 120 to 250 ° C. is preferable from the viewpoint of safety because the temperature rises during kneading and the solvent is easily evaporated. Examples of water-soluble solvents include 2- (methoxymethoxy) ethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether. , Triethylene glycol, triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, low molecular weight Examples thereof include polypropylene glycol.

  In the present invention, the pigment is preferably contained in the ink-jet ink in the range of 3 to 15% by mass in order to obtain a sufficient concentration and sufficient light resistance.

  Examples of the pigment dispersant preferably used in the present invention include a hydroxyl group-containing carboxylic acid ester, a salt of a long chain polyaminoamide and a high molecular weight acid ester, a salt of a high molecular weight polycarboxylic acid, a salt of a long chain polyaminoamide and a polar acid ester, Molecular weight unsaturated acid ester, polymer copolymer, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formalin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphorus Examples include acid esters, polyoxyethylene nonylphenyl ether, stearylamine acetate, and pigment derivatives.

  Specific examples of the pigment dispersant include "Anti-Terra-U (polyaminoamide phosphate)", "Anti-Terra-203 / 204 (high molecular weight polycarboxylate)" manufactured by BYK Chemie, "Disperbyk-101 ( Polyaminoamide phosphate and acid ester), 107 (hydroxyl group-containing carboxylic acid ester), 110 (copolymer containing an acid group), 130 (polyamide), 161, 162, 163, 164, 165, 166, 170 (polymer) Copolymer)), "400", "Bykumen" (high molecular weight unsaturated acid ester), "BYK-P104, P105 (high molecular weight unsaturated acid polycarboxylic acid)", "P104S, 240S (high molecular weight unsaturated acid) Polycarboxylic acid and silicon system "," Lactimon (long chain amine and unsaturated acid polycarl) Phosphate and silicon) ", and the like.

  Also, “Efka CHEMICALS” “Efka 44, 46, 47, 48, 49, 54, 63, 64, 65, 66, 71, 701, 764, 766”, “Efka Polymer 100 (modified polyacrylate), 150 (aliphatic) System modified polymer), 400, 401, 402, 403, 450, 451, 452, 453 (modified polyacrylate), 745 (copper phthalocyanine system) "," Kyoeisha Chemical Co., Ltd. "" Floren TG-710 (urethane oligomer) "," “Flonon SH-290, SP-1000”, “Polyflow No. 50E, No. 300 (acrylic copolymer)”, “Disparon KS-860, 873SN, 874 (polymer dispersing agent), # 2150, manufactured by Enomoto Kasei Co., Ltd. (Aliphatic polycarboxylic acid), # 7004 (polyether ester type) " It is.

  Further, “Demol RN, N (Naphthalenesulfonic acid formalin condensate sodium salt), MS, C, SN-B (aromatic sulfonic acid formalin condensate sodium salt), EP”, “Homogenol L-18 (poly) Carboxylic acid type polymer) "," Emulgen 920, 930, 931, 935, 950, 985 (polyoxyethylene nonyl phenyl ether) "," Acetamine 24 (coconut amine acetate), 86 (stearyl amine acetate) ", General Corporation "Solspers 5000 (phthalocyanine ammonium salt type), 13240, 13940 (polyesteramine type), 17000 (fatty acid amine type), 24000, 32000", Nikko Chemical's "Nikkor T106 (polyoxyethylene sorbitan monooleate), M" S-IEX (polyoxyethylene monostearate), Hexagline 4-0 (hexaglyceryl ruthenate Huwei rate) ", and the like.

  In the ink according to the present invention, the pigment dispersant is preferably contained in the ink in the range of 0.1 to 10% by mass.

  The ink-jet ink according to the present invention is produced by well dispersing the pigment together with an active energy ray-curable compound and a pigment dispersant using a normal dispersing machine such as a sand mill. It is preferable to prepare a concentrated solution having a high pigment concentration in advance and dilute with an active energy ray-curable compound. Sufficient dispersion is possible even with dispersion by an ordinary disperser, so that excessive dispersion energy is not applied and a large dispersion time is not required. Therefore, an ink having excellent stability that is unlikely to cause deterioration during dispersion of the ink components is prepared. The ink is preferably filtered through a filter having a pore size of 3 μm or less, more preferably 1 μm or less.

  In the ink-jet ink according to the present invention, the viscosity at 25 ° C. is preferably adjusted to be as high as 5 to 50 mPa · s from the viewpoint of ejection stability. An ink having a viscosity of 5 to 50 mPa · s at 25 ° C. exhibits stable ejection characteristics from a normal head having a frequency of 4 to 10 kHz to a high frequency head of 10 to 50 kHz.

  In addition, the ink-jet ink according to the present invention preferably has a conductivity of 10 μS / cm or less in a piezo head and does not cause electrical corrosion inside the head.

  Further, in the continuous type, it is necessary to adjust the electric conductivity by the electrolyte. In this case, it is necessary to adjust the electric conductivity to 0.5 mS / cm or more.

  As the base material (recording medium) used in the present invention, all of a wide range of synthetic resins conventionally used in various applications are targeted. Specifically, for example, polyester, polyvinyl chloride, polyethylene, polyurethane, Examples include polypropylene, acrylic resin, polycarbonate, polystyrene, acrylonitrile-butadiene-styrene copolymer, polyethylene terephthalate, polybutadiene terephthalate, and the like, and the thickness and shape of these synthetic resin substrates are not limited at all.

  In the present invention, ink is first supplied to a printer head of an ink jet recording printer, discharged from the printer head onto a substrate, and then irradiated with active energy rays such as ultraviolet rays or electron beams. As a result, the ink on the recording medium is quickly cured.

  In addition, as a light source of an active energy ray, when irradiating ultraviolet rays, a mercury arc lamp, a xenon arc lamp, a fluorescent lamp, a carbon arc lamp, a tungsten-halogen copy lamp, and sunlight can be used, for example. . In the case of curing with an electron beam, it is usually cured with an electron beam having an energy of 300 eV or less, but it can also be cured instantaneously with an irradiation amount of 1 to 5 Mrad.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. Moreover, the part and% in an Example show a mass part and mass%, respectively.

<Preparation of ink>
The pigment (P1), the dispersant (S32000) described in Table 1, the oxetane ring-containing compound (OX211), the oxirane group-containing compound (CEL2021P), and the vinyl ether compound (DVE-3) are all put in a sand mill for 4 hours. Dispersion was performed to obtain each active energy ray-curable ink stock solution. Next, a cationic photopolymerization initiator (SP-152) was added to each ink stock solution and mixed gently until the cationic photopolymerization initiator was dissolved. A curable inkjet ink was obtained.
In addition, the numerical value of the bottom line of Table 1 represents a mass part.

The details of each additive described in Table 1 are as follows.
Pigment (P1):
Crude copper phthalocyanine (Copper phthalocyanine manufactured by Toyo Ink Mfg. Co., Ltd.) 250 parts Sodium chloride 2500 parts Polyethylene glycol (Polyethylene glycol 300 manufactured by Tokyo Chemical Industry Co., Ltd.) 160 parts The above materials are made of styrene 5.55 L (1 gallon) kneader (Inoue Seisakusho Co., Ltd.) And kneaded for 3 hours. Next, the mixture was poured into 2.5 liters of warm water, stirred for about 1 hour with a high-speed mixer while heating to about 80 ° C. to form a slurry, and filtration and washing were repeated 5 times to remove sodium chloride and The solvent was removed, and then dried by spray drying to obtain pigment P1.
Oxetane ring-containing compound (OXT-221): di [1-ethyl (3-oxetanyl)] methyl ether, manufactured by Toagosei Co., Ltd.
-Oxirane group-containing compound (CEL2021P): Alicyclic epoxy compound manufactured by Daicel Corporation.
Vinyl ether compound (DVE-3): Triethylene glycol divinyl ether, manufactured by ISP.
Pigment dispersant (S32000): Aliphatic modified dispersant Solspers 32000 manufactured by Geneca Corporation.
-Photocationic polymerization initiator (SP-152): Triphenylsulfonium salt Adekaoptomer SP-152 manufactured by Asahi Denka Co., Ltd.

"Evaluation methods"
[Production of printed matter]
The ink is printed on polyethylene terephthalate (base material) which has been subjected to pretreatment with polyethylene terephthalate with an inkjet printer having a piezo head, and then the substrate is irradiated with a UV irradiation device (8 cold cathode tubes: 20 W output). Was cured at a conveying speed of 500 mm / sec to produce a printed matter.

[Curing property]
After UV irradiation, the curability was evaluated by touching the cured surface with a finger to see if any tack remained.
○: Ink cannot be removed.
X: Ink can be removed.

[Membrane strength]
The strength of the cured film was determined by a nail scratch test.
○: The printed image cannot be taken even when scratched.
Δ: Print image is slightly removed when scratched strongly.
X: The printed image is easily removed when scratched.

[Adhesion]
For the printed image produced above, a sample that does not scratch the printed surface at all, and in accordance with JIS K 5400, 11 cuts are made on the printed surface at 1 mm intervals vertically and horizontally, and 1 mm square grids are formed. 100 samples were prepared, cellotape (registered trademark) was affixed on each print surface, quickly peeled off at an angle of 90 degrees, and the remaining print image or grid pattern remaining in accordance with the following criteria evaluated. Use a sample cured at 25 ° C. and 45% RH.
○: No peeling of the printed image was observed even in the cross-cut test.
Δ: In the cross-cut test, some ink peeling is recognized, but almost no peeling is observed unless the ink surface is scratched.
X: Peeling with cello tape (registered trademark) is easily recognized under both conditions.

[Image bleeding]
(Double-circle): There is no bleeding and printability is also favorable.
○: Slight bleeding and printing disturbance occur.
Δ: Although there is bleeding, the characters can be identified.
X: Characters cannot be identified due to bleeding.

  The results are shown in Table 2.

  Note that Nos. 1 to 3 of the ink jet recording method (image forming method) in Table 2 represent the forms of the ink jet recording method.

《Comparative example》
[Corona treatment]
Using a solid state corona treatment machine 6KVA model manufactured by Pillar, both surfaces of the support were treated at room temperature at 20 m / min. This was designated as Comparative Example 1.

From the current and voltage readings at this time, it was found that the support was processed at 0.375 KV · A · min / m ² . At this time, the treatment and frequency were 9.6 kHz, and the gap clearance between the electrode and the dielectric roll was 1.6 mm.

[UV curable undercoat layer]
A composition obtained by removing the pigment from the ink composition of the example of the present invention was adjusted in the same manner as the adjustment of the ink of the example, and this was designated as Comparative Example 2. Further, Comparative Example 3 was obtained without any pretreatment.

  From the results shown in Table 2, it can be seen that the recording method of the present invention enables high productivity, low cost, no blur, high image quality, and excellent substrate adhesion.

Claims (13)

An ink jet recording method comprising a step of performing pretreatment on a surface of a substrate to form a pretreatment layer and a step of recording by discharging an active energy ray-curable ink jet ink onto the pretreatment layer. An inkjet recording method using an active energy ray-curable inkjet ink, wherein the pretreatment agent is a polymer latex. The inkjet recording method using an active energy ray-curable inkjet ink according to claim 1, wherein the polymer latex contains a polymer compound having a cationic polymerization reactive group. The inkjet recording method using an active energy ray-curable inkjet ink according to claim 1 or 2, wherein the active energy ray-curable inkjet ink contains a cationic polymerizable compound. The active energy according to any one of claims 1 to 3, wherein the cationic polymerizable compound is at least one selected from an oxetane ring-containing compound, an oxirane group-containing compound, and a vinyl ether compound. An inkjet recording method using a linear curable inkjet ink. The inkjet recording method using the active energy ray-curable inkjet ink according to any one of claims 1 to 4, wherein the active energy ray-curable inkjet ink contains a cationic photopolymerization initiator. . The inkjet recording method using an active energy ray-curable inkjet ink according to any one of claims 1 to 5, wherein the active energy ray-curable inkjet ink contains a pigment and a pigment dispersant. . The inkjet recording method using an active energy ray-curable inkjet ink according to claim 6, wherein the pigment is pigment particles having an average particle size of 10 to 150 nm. The active energy ray-curable inkjet ink according to any one of claims 1 to 7, wherein the active energy ray-curable inkjet ink has a viscosity at 25 ° C of 5 to 50 mPa · s. Inkjet recording method. The ink-jet recording method using an active energy ray-curable ink-jet ink according to any one of claims 1 to 8, wherein the moisture content of the pretreatment layer is 0.01 to 5% by mass. . 10. The inkjet recording method using an active energy ray-curable inkjet ink according to claim 1, wherein the pretreatment layer has a thickness of 0.001 μm to 2 μm. The step of performing pretreatment using the pretreatment agent to form a pretreatment layer and the step of performing recording by discharging an active energy ray-curable inkjet ink onto the pretreatment layer are performed continuously. An inkjet recording method using the active energy ray-curable inkjet ink according to any one of claims 1 to 10. 12. The method according to claim 1, further comprising a step of heating the base material after a step of forming a pretreatment layer by performing a pretreatment using the pretreatment agent. An inkjet recording method using an active energy ray-curable inkjet ink. An active energy ray-curable inkjet recording apparatus, which is used in the inkjet recording method using the active energy ray-curable inkjet ink according to any one of claims 1 to 12.