JP6124353B2 - Printing method and printed matter - Google Patents

Description

  The present invention relates to a printing method using an active energy ray-curable inkjet ink composition and a printed matter obtained by the printing method, and particularly relates to a printing method capable of improving the adhesion of a printing layer to a substrate. The active energy ray-curable inkjet ink composition is an ink composition for an inkjet printer, and means an ink composition that can be cured by irradiation with active energy rays such as ultraviolet rays.

  In recent years, in order to improve the printing performance and productivity of the active energy ray-curable inkjet ink, various proposals have been made from both the ink composition and the configuration of the printing apparatus. For example, in Japanese Patent Application Laid-Open No. 2007-160527 (Patent Document 1), a color material and a hydrophilic main chain have a plurality of side chains and can be cross-linked between side chains by irradiating active energy rays. An ink jet recording method using an ink jet ink containing a polymer compound has been proposed. In this method, by specifying the irradiation energy of an active energy ray at a specific wavelength, color bleed resistance, smoothness of a recorded image, and It is described that fixability can be improved. It is also described that the recorded image can be dried with a heater or the like after the step of irradiating active energy rays.

  Japanese Patent Laid-Open No. 2007-76225 (Patent Document 2) proposes an ink jet recording method using the same ink jet ink as in Patent Document 1, and in this method, the ink is preliminarily heated on a recording medium. It is described that the ink can be discharged and the printing quality can be improved. Patent Document 2 also describes that the recorded image can be dried with a heater or the like after the step of irradiating the active energy ray.

JP 2007-160527 A JP 2007-76225 A

  As described above, in the conventional ink jet recording method as described in Patent Document 1 and Patent Document 2, an ink jet ink containing an active energy ray-curable polymer compound is discharged onto a recording medium and irradiated with active energy rays. By doing so, it is known that the fixability of the recorded image can be improved. Such ink-jet inks may use a solvent such as water or an organic solvent. In order to dry these solvents, it is also known that a recorded image can be dried by heating after the step of irradiating active energy rays. ing.

  Under such circumstances, an object of the present invention is to provide a printing method capable of improving the adhesion of a printing layer to a substrate using a heating means from a viewpoint different from that of the conventional technique. Moreover, the other objective of this invention is to provide a printed matter provided with the printing layer which is excellent in the adhesiveness with respect to a base material.

  As a result of intensive studies to achieve the above object, the present inventor has heated a print layer formed by printing using an active energy ray-curable inkjet ink composition, and then heated the print layer by irradiation with near infrared rays. As a result, it was found that the adhesion of the printed layer to the substrate can be improved, and the present invention has been completed. This is because near infrared rays can heat the printed layer more efficiently than other electromagnetic waves, so the entire printed layer including the deep part of the printed layer can be heated, and the entire printed layer softens and adheres to the substrate. It is thought that it is because the sex is improved.

That is, the printing method of the present invention includes a printing step in which a printing layer is formed on a substrate by printing using one or more kinds of active energy ray-curable inkjet ink compositions;
A curing step for curing the printed layer formed on the substrate;
Heating the cured printed layer by irradiation with near infrared rays.

  In a preferred embodiment of the printing method of the present invention, the dominant wavelength of near infrared rays applied to the print layer is 0.8 μm to 2.0 μm.

  In another preferred embodiment of the printing method of the present invention, in the heating step, the temperature of the printing layer is 100 ° C to 250 ° C.

  In another preferred embodiment of the printing method of the present invention, the active energy ray-curable inkjet ink composition includes a pigment, a radical polymerizable monomer having 1 to 2 functional groups, and a photopolymerization initiator.

  In another preferred embodiment of the printing method of the present invention, when a plurality of types of active energy ray-curable inkjet ink compositions are used in the printing step, the cured product of each active energy ray-curable inkjet ink composition has a wavelength. The difference in near-infrared absorptance of 0.8 μm to 2.0 μm is in the range of 50% or less.

  Moreover, the printed matter of the present invention is obtained by the above printing method.

  According to the printing method of the present invention, after curing a printing layer formed by printing using an active energy ray-curable inkjet ink composition, the printing layer is heated by irradiation with near infrared rays, thereby printing on a substrate. The printing method which can improve the adhesiveness of a layer can be provided.

  According to the printed matter of the present invention, it is possible to provide a printed matter provided with a printed layer having excellent adhesion to a substrate.

<Printing method>
The printing method of the present invention will be described in detail below. The printing method of the present invention comprises a printing step in which a printing layer is formed on a substrate by printing using one or more kinds of active energy ray-curable inkjet ink compositions, and a printing layer formed on the substrate. It includes a curing step for curing and a heating step for heating the cured printed layer by irradiation with near infrared rays. According to the printing method of the present invention, after curing a printing layer formed by printing using an active energy ray-curable inkjet ink composition, the printing layer is heated by irradiation with near infrared rays, thereby printing on a substrate. The adhesion of the layer can be improved. In the printing method of the present invention, near infrared irradiation is used as a heating means, and heat can be efficiently transmitted to the entire printed layer. On the other hand, for example, when irradiating electromagnetic waves having different wavelength ranges such as far infrared rays, it takes time to heat the printed layer and it is difficult to uniformly heat the printed layer. It is thought that it cannot be improved sufficiently.

  In the printing method of the present invention, first, a printing process is performed in which a printing layer is formed on a substrate by printing using one or more kinds of active energy ray-curable inkjet ink compositions.

  Although the said base material is not specifically limited, As the material, Plastics, such as ABS resin, a polycarbonate, a polyvinyl chloride, a polystyrene, a polymethylmethacrylate (PMMA), a polyethylene terephthalate (PET), Examples thereof include metals such as stainless steel and aluminum, glasses, ceramics, papers (including those whose surface is coated with a resin), and the like. Moreover, as a shape of a base material, there exist plate shape etc., for example.

  The active energy ray-curable inkjet ink composition is not particularly limited, but preferably contains a pigment, a radical polymerizable monomer having 1 to 2 functional groups, and a photopolymerization initiator. In particular, by using a radically polymerizable monomer having 1 to 2 functional groups, the curability of the print layer and the strength of the print layer can be controlled. In addition, the functional group in this invention refers to the functional group which shows the reactivity at the time of active energy ray irradiation, and an acryloyloxy group and a methacryloyloxy group are suitable. The radical polymerizable monomer is a radical polymerizable monomer having a functional group number of 1 (also referred to as a monofunctional monomer), a radical polymerizable monomer having a functional group number of 2 (also referred to as a bifunctional monomer), and the number of functional groups. Although it can be classified into radical polymerizable monomers having 3 or more functional groups (also referred to as trifunctional or more polyfunctional monomers), the active energy ray-curable inkjet ink composition is a radical having 3 or more functional groups. A polymerizable monomer can also be included.

  Among the radical polymerizable monomers, the monofunctional monomer preferably has a molecular weight of 1000 or less. Specific examples include stearyl acrylate, acryloylmorpholine, tridecyl acrylate, lauryl acrylate, N, N-dimethylacrylamide, decyl. Acrylate, phenoxyethyl acrylate, isodecyl acrylate, isobornyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, isooctyl acrylate, octyl acrylate, dicyclopentenyloxyethyl acrylate, cyclohexyl acrylate, N-vinylcaprolactam, isoamyl acrylate 2-ethylhexyl-diglycol acrylate, EO (ethylene oxide) modified 2-ethylhexyl Acrylate, neopentyl glycol acrylate benzoate, N-vinyl-2-pyrrolidone, N-vinylimidazole, tetrahydrofurfuryl acrylate, methoxydipropylene glycol acrylate, (2-methyl-2-ethyl-1,3-dioxolane- 4-yl) methyl acrylate, cyclic trimethylolpropane formal acrylate, and ethoxy-diethylene glycol acrylate. Among these, isobornyl acrylate, phenoxyethyl acrylate, methoxydipropylene glycol acrylate, cyclohexyl acrylate, and tetrahydrofurfuryl acrylate are preferable. In addition, these monofunctional monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  Among the radical polymerizable monomers, the bifunctional monomer preferably has a molecular weight of 1000 or less. Specific examples include 1,10-decanediol diacrylate and 2-methyl-1,8-octanediol diacrylate. 2-butyl-2-ethyl-1,3-propanediol diacrylate, 1,9-nonanediol diacrylate, 1,8-octanediol diacrylate, 1,7-heptanediol diacrylate, polytetramethylene glycol diacrylate Acrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, hydroxypivalate neopentyl glycol diacrylate, tripropylene glycol diacrylate, 1,4 Butanediol diacrylate, and dipropylene glycol diacrylate, and the like. Among these, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate and neopentyl glycol diacrylate are preferable. In addition, these bifunctional monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the above active energy ray-curable inkjet ink composition, the total content of the radical polymerizable monomers having 1 to 2 functional groups is selected from the viewpoint of controlling the curability of the printing layer and the strength of the printing layer. It is preferable that it is 50-90 mass% in the total mass of.

  Among the above radical polymerizable monomers, the trifunctional or higher polyfunctional monomer preferably has 3 to 6 functional groups, and preferably has a molecular weight of less than 2000. Specific examples of the trifunctional or higher polyfunctional monomer include trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated glycerin triacrylate, tetramethylolmethane. Examples include triacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, EO-modified diglycerin tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate. In addition, these polyfunctional monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the above active energy ray-curable inkjet ink composition, the content of the radical polymerizable monomer having 3 or more functional groups is the total mass of the ink composition from the viewpoint of controlling the curability of the print layer and the strength of the print layer. It is preferable that it is 1-20 mass% inside.

Moreover, in the said active energy ray hardening-type inkjet ink composition, in order to raise the intensity | strength of a printing layer, you may use an acrylate oligomer. An acrylate oligomer is an oligomer having one or more acryloyloxy groups (CH ₂ ═CHCOO—), and the number of functional groups is preferably 3-6. The acrylate oligomer preferably has a molecular weight of 2000 to 20000. In addition, this molecular weight is a weight average molecular weight of polystyrene conversion. Specific examples of the acrylate oligomer include aminoacrylate oligomer [acrylate oligomer having a plurality of amino groups (-NH ₂ )], urethane acrylate oligomer [acrylate oligomer having a plurality of urethane bonds (-NHCOO-)], epoxy acrylate oligomer [ Acrylate oligomer having a plurality of epoxy groups], silicone acrylate oligomer [acrylate oligomer having a plurality of siloxane bonds (—SiO—)], ester acrylate oligomer [acrylate oligomer having a plurality of ester bonds (—COO—)] and butadiene acrylate oligomer [butadiene Acrylate oligomer having a plurality of units] and the like. Among these, urethane acrylate oligomers are preferable from the viewpoint of weather resistance and adhesion, and aliphatic urethane acrylate oligomers having no aromatic ring in the structure are more preferable. In addition, content of an acrylate oligomer is 1-10 mass% in the total mass of an ink composition, for example.

Specific examples of the acrylate oligomer include the following. In addition, these acrylate oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.
Beam set 502H, beam set 505A-6, beam set 550B, beam set 575, beam set AQ-17 (manufactured by Arakawa Chemical Industries),
UA-306H, UA-306I, UA-510H, UF-8001G (manufactured by Kyoeisha Chemical Co., Ltd.),
CN929, CN940, CN944B85, CN959, CN961E75, CN961H81, CN962, CN963A80, CN963B80, CN963E75, CN963E80, CN963J75, CN964, CN964A85, CN964E75, CN965, CN965A80, CN966A80, CN966B85, CN966H90, CN966J75, CN966R60, CN968, CN980, CN981, CN981A75, CN981B88, CN982A75, CN982B88, CN982E75, CN982P90, CN983, CN985B88, CN989, CN991, CN996, CN9001, CN9002, CN9004, CN9005, CN9006, CN9007 CN9009, CN9010, CN9011, CN9014, CN9178, CN9788, CN9893 (manufactured by Sartomer Co., Ltd.),
U-4HA, U-6HA, U-6LPA, UA-1100H, UA-53H, UA-33H, U-200PA, UA-4200, UA-122P (manufactured by Shin-Nakamura Chemical Co., Ltd.),
New Frontier R-1214, New Frontier R-1301, New Frontier R-1304, New Frontier R-1306X, New Frontier R-1150D (Daiichi Kogyo Seiyaku Co., Ltd.),
EBECRYL230, EBECRYL244, EBECRYL245, EBECRYL264, EBECRYL265, EBECRYL270, EBECRYL284, EBECRYL285, EBECRYL294, EBECRYL1290, EBECRYL1290, EBECRYL1290, EBECRYL1290, EBECRYL1290, EBECRYL1290
UV-1700B, UV-7600B, UV-7605B, UV-6630B, UV-7000B, UV-7461TE, UV-3000B, UV-3310B, UV-3520TL, UV-3700B (manufactured by Nippon Synthetic Chemical),
Art Resin UN-333, UN-1255, UN-2600, UN-2700, UN-5500, UN-5507, UN-6060P, UN-6200, UN-6300, UN-6301, UN-7600, UN-7700, UN-9000PEP, UN-9200A, UN-3320HA, UN-3320HC, UN-904 (manufactured by Negami Kogyo Co., Ltd.)

  The photopolymerization initiator used in the active energy ray-curable inkjet ink composition has an action of initiating polymerization of the above-described radical polymerizable monomer and acrylate oligomer when irradiated with active energy rays. Further, the content of the photopolymerization initiator is preferably 1 to 25% by mass, and more preferably 1 to 15% by mass, based on the total mass of the ink composition. When the content of the photopolymerization initiator is less than 1% by mass, the printed layer may be poorly cured. When the content exceeds 25% by mass, precipitates are generated at low temperatures and ink ejection becomes unstable. There is. Furthermore, in order to accelerate the initiation reaction of the photopolymerization initiator, an auxiliary such as a photosensitizer can be used in combination.

  Examples of the photopolymerization initiator include benzophenone compounds, acetophenone compounds, thioxanthone compounds, phosphine oxide compounds, etc. From the viewpoint of curability, the wavelength of the active energy ray to be irradiated and the photopolymerization initiator It is preferable that the absorption wavelengths overlap as much as possible.

As a specific example of the photopolymerization initiator,
2,2-dimethoxy-1,2-diphenylethane-1-one,
1-hydroxy-cyclohexyl-phenyl-ketone,
2-hydroxy-2-methyl-1-phenylpropan-1-one,
Benzophenone,
1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one,
2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) -benzyl] -phenyl} -2-methyl-propan-1-one,
Phenylglyoxylic acid methyl ester,
2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one,
2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone,
2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one,
Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide,
Bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide,
2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide,
1,2-octanedione, 1- [4- (phenylthio) -2- (O-benzoyloxime)],
Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime),
2,4-diethylthioxanthone,
2-isopropylthioxanthone,
Examples include 2-chlorothioxanthone. Among these, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide is preferable from the viewpoint of curability of the printed layer. In addition, these photoinitiators may be used individually by 1 type, and may be used in combination of 2 or more type.

  The active energy ray-curable inkjet ink composition may further contain a light stabilizer. The light stabilizer has an action of absorbing ultraviolet rays and preventing deterioration due to ultraviolet rays. Examples of the light stabilizer include cyanoacrylate compounds, benzophenone compounds, benzoate compounds, benzotriazole compounds, hydroxyphenyl triazine compounds, benzylidene camphor compounds, inorganic fine particles, etc. Among them, ultraviolet absorption has a shorter wavelength. The hydroxyphenyltriazine compound is preferably from the viewpoint of curability of the printed layer. From the viewpoint of curability, it is preferable that the wavelength of the active energy ray to be irradiated and the absorption wavelength of the light stabilizer do not overlap as much as possible. The content of the light stabilizer is preferably 0.1 to 15% by mass, more preferably 0.2 to 5% by mass, based on the total mass of the ink composition. When the content of the light stabilizer is less than 0.1% by mass, a sufficient ultraviolet ray absorbing effect cannot be obtained, and when it exceeds 15% by mass, the printed layer may be poorly cured.

As a specific example of the light stabilizer,
2,4-dihydroxybenzophenone,
2-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-methoxybenzophenone-5-sulfonic acid,
2-hydroxy-4-octoxybenzophenone,
2-hydroxy-4-dodecyloxybenzophenone-2-hydroxy-4-benzyloxybenzophenone,
Bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane,
2,2′-dihydroxy-4-methoxybenzophenone,
2,2′-dihydroxy-4,4′-dimethoxybenzophenone,
2,2 ′, 4,4′-tetrahydroxybenzophenone,
2-hydroxy-4-methoxy-2′-carboxybenzophenone,
2- (2′-hydroxy-5′-methylphenyl) benzotriazole 2- [2′-hydroxy-3 ′, 5′-bis (α, α- (dimethylbenzyl) phenyl] benzotriazole,
2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole,
2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole,
2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) -5-chlorobenzotriazole,
2- (2′-hydroxy-3 ′, 5′-di-t-amylphenyl) benzotriazole,
2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole,
2,2′-methylene-bis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol],
A condensate of methyl-3- [3-tert-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate and polyethylene glycol;
2- (2-hydroxyphenyl) benzotriazole,
2- (2′-hydroxy-5′-methylphenyl) benzotriazole,
2,6-di-tert-butylphenyl-3 ′, 5′-di-tert-butyl-4′-hydroxybenzoate,
And hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate. In addition, these light stabilizers may be used individually by 1 type, and may be used in combination of 2 or more type.

  The active energy ray-curable inkjet ink composition may further contain a colorant such as a dye or a pigment, but preferably contains a pigment from the viewpoint of weather resistance. In addition, content of a coloring agent (For example, when an ink composition contains a pigment, content of a pigment) is 0.1-10 mass% in the total mass of an ink composition, for example. Moreover, a coloring agent may be used individually by 1 type, and may be used in combination of 2 or more type.

As a specific example of the colorant,
C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 13, 14, 15, 16, 17, 24, 32, 34, 35, 36, 37, 41, 42, 43, 49, 53, 55, 60, 61, 62, 63, 65, 73, 74, 75, 77, 81, 83, 87, 93, 94, 95, 97, 98, 99, 100, 101, 104, 105, 106, 108, 109, 110, 111, 113, 114, 116, 117, 119, 120, 123, 124, 126, 127, 128, 129, 130, 133, 138, 139, 150, 151, 152, 153, 154, 155, 165, 167, 168, 169, 170, 172, 173, 174, 175, 176, 179, 180, 181, 182, 183, 184, 185, 91,193,194,199,205,206,209,212,213,214,215,219,
C. I. Pigment Orange 1, 2, 3, 4, 5, 13, 15, 16, 17, 19, 20, 21, 24, 31, 34, 36, 38, 40, 43, 46, 48, 49, 51, 60, 61, 62, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 81,
C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 21, 22, 23, 31, 32, 38, 41, 48, 48: 1, 48: 2, 48: 3, 48: 4, 48: 5, 49, 52, 52: 1, 52: 2, 53: 1, 54, 57: 1, 58, 60: 1, 63, 64: 1, 68, 81: 1, 83, 88, 89, 95, 101, 104, 105, 108, 112, 114, 119, 122, 123, 136, 144, 146, 147, 149, 150, 164, 166, 168, 169, 170, 171, 172, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 20 208, 209, 210, 211, 213, 214, 216, 220, 220, 221, 224, 226, 237, 238, 239, 242, 245, 247, 248, 251, 253, 254, 255, 256, 257 258, 260, 262, 263, 264, 266, 268, 269, 270, 271, 272, 279,
C. I. Pigment Violet 1, 2, 3, 3: 1, 3: 3, 5: 1, 13, 15, 16, 17, 19, 23, 25, 27, 29, 31, 32, 36, 37, 38, 42, 50,
C. I. Pigment Blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 5, 15: 6, 16, 17: 1, 24, 24: 1, 25, 26, 27, 28, 29, 36, 56, 60, 61, 62, 63, 75, 79, 80,
C. I. Pigment Green 1, 4, 7, 8, 10, 15, 17, 26, 36, 50,
C. I. Pigment Brown 5, 6, 23, 24, 25, 32, 41, 42,
C. I. Pigment Black 1, 6, 7, 9, 10, 11, 20, 31, 32, 34,
C. I. Pigment White 1, 2, 4, 5, 6, 7, 11, 12, 18, 19, 21, 22, 23, 26, 27, 28,
Examples include aluminum flakes, glass flakes, and hollow particles.

Among these, C.I. from the viewpoint of weather resistance and color reproducibility of the printed matter. I. PigmentBlack7,
C. I. PigmentBlue 15: 3, C.I. I. Pigment Blue 15: 4, C.I. I. PigmentBlue 28,
C. I. PigmentRed101, C.I. I. PigmentRed122,
C. I. PigmentRed 202, C.I. I. PigmentRed254,
C. I. PigmentRed282,
C. I. PigmentViolet 19,
C. I. PigmentWhite 7,
C. I. Pigment Yellow 42, C.I. I. Pigment Yellow 120,
C. I. Pigment Yellow 138, C.I. I. Pigment Yellow 139, C.I. I. Pigment Yellow 150, C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 155, C.I. I. Pigment Yellow 213 is preferable.

  When a pigment is used as the colorant, the pigment particles dispersed in the ink composition have a volume average particle diameter of 0.05 to 0.4 μm and a volume maximum particle diameter of 0 from the viewpoint of ejection stability. It is preferably 2 to 1 μm. When the volume average particle diameter is larger than 0.4 μm and the volume maximum particle diameter is larger than 1 μm, it tends to be difficult to stably discharge the ink composition. The volume average particle diameter and the volume maximum particle diameter can be measured by a measuring instrument using a dynamic light scattering method.

  The active energy ray-curable inkjet ink composition may further contain a pigment dispersant as necessary in order to disperse the pigment. In addition, content of a pigment dispersant is 0.1-5 mass% in the total mass of an ink composition, for example. Moreover, a pigment dispersant may be used individually by 1 type, and may be used in combination of 2 or more type.

Specific examples of the pigment dispersant include
ANTI-TERRA-U, ANTI-TERRA-U100,
ANTI-TERRA-204, ANTI-TERRA-205,
DISPERBYK-101, DISPERBYK-102,
DISPERBYK-103, DISPERBYK-106,
DISPERBYK-108, DISPERBYK-109,
DISPERBYK-110, DISPERBYK-111,
DISPERBYK-112, DISPERBYK-116,
DISPERBYK-130, DISPERBYK-140,
DISPERBYK-142, DISPERBYK-145,
DISPERBYK-161, DISPERBYK-162,
DISPERBYK-163, DISPERBYK-164,
DISPERBYK-166, DISPERBYK-167,
DISPERBYK-168, DISPERBYK-170,
DISPERBYK-171, DISPERBYK-174,
DISPERBYK-180, DISPERBYK-182,
DISPERBYK-183, DISPERBYK-184,
DISPERBYK-185, DISPERBYK-2000,
DISPERBYK-2001, DISPERBYK-2008,
DISPERBYK-2009, DISPERBYK-2020,
DISPERBYK-2025, DISPERBYK-2050,
DISPERBYK-2070, DISPERBYK-2096,
DISPERBYK-2150, DISPERBYK-2155,
DISPERBYK-2163, DISPERBYK-2164,
BYK-P104, BYK-P104S, BYK-P105,
BYK-9076, BYK-9077, BYK-220S, BYKJET-9150, BYKJET-9151 (above, manufactured by Big Chemie Japan),
Solsperse 3000, Solsperse 5000,
Solsperse 9000, Solsperse 11200,
Solsperse 13240, Solsperse 13650,
Solsperse 13940, Solsperse 16000,
Solsperse 17000, Solsperse 18000,
Solsperse 20000, Solsperse 21000,
Solsperse 24000SC, Solsperse 24000GR,
Solsperse 26000, Solsperse 27000,
Solsperse 28000, Solsperse 32000,
Solsperse 32500, Solsperse 32550,
Solsperse 32600, Solsperse 33000,
Solsperse 34750, Solsperse 35100,
Solsperse 35200, Solsperse 36000,
Solsperse 36600, Solsperse 37500,
Solsperse 38500, Solsperse 39000,
Solsperse 41000, Solsperse 54000,
Solsperse 55000, Solsperse 56000,
Solsperse 71000, Solsperse 76500,
Solsperse X300 (above, manufactured by Lubrizol),
Disparon DA-7301, Disparon DA-325,
Disparon DA-375, Disparon DA-234 (above, manufactured by Enomoto Kasei Co., Ltd.)
FLOREN AF-1000, FLOREN DOPA-15B, FLOREN DOPA-15BHFS, FLOREN DOPA-17HF, FLOREN DOPA-22, FLOREN DOPA-33, FLOREN G-600, FLOREN G-700, FLOREN G-700AMP, FLOREN G-700DMEA, Floren G-820, Floren G-900, Floren GW-1500, Floren KDG-2400, Floren NC-500, Floren WK-13E, (manufactured by Kyoeisha Chemical Co., Ltd.)
TEGO Dispers 610, TEGO Dispers 610S,
TEGO Dispers 630, TEGO Dispers 650,
TEGO Dispers 652, TEGO Dispers 655,
TEGO Dispers 662C, TEGO Dispers 670,
TEGO Dispers 685, TEGO Dispers 700,
TEGO Dispers 710, TEGO Dispers 740W,
LIPOTIN A, LIPOTIN BL,
LIPOTIN DB, LIPOTIN SB (above, manufactured by Evonik Degussa),
PB821, PB822, PN411, PA111 (above, manufactured by Ajinomoto Fine Techno Co.),
Texahole 963, Texahole 964, Texahole 987, Texahole P61, Texahole P63, Texahole 3250, Texahole SF71, Texahole UV20, Texahole UV21 (above, manufactured by Cognis)
BorchiGen SN88, BorchiGen 0451 (above, manufactured by Bochas) and the like.

  The active energy ray-curable inkjet ink composition includes, as other components, a polymerization inhibitor, an antioxidant, a silane coupling agent, a plasticizer, a rust inhibitor, a solvent, a non-reactive polymer, a filler, and pH adjustment. Additives such as an agent, an antifoaming agent, a charge control agent, a stress relaxation agent, a penetrating agent, a light guide material, a bright material, a magnetic material, a phosphor, and a surface conditioner may be used as necessary.

  The active energy ray-curable inkjet ink composition is a filter having a pore size of about 1/10 or less of the nozzle diameter of an inkjet print head to be used, if necessary, by mixing various components appropriately selected as necessary. And the resulting mixture can be prepared by filtration. In the ink-jet ink composition, desired viscosity and surface tension can be achieved by appropriately adjusting the compounding ratio of the compounding agents used.

  The active energy ray-curable inkjet ink composition preferably has a viscosity at 40 ° C. of 3 to 15 mPa · s, and more preferably 5 to 10 mPa · s. If the ink viscosity at 40 ° C. is within the above specified range, good ejection stability can be obtained. The ink viscosity can be measured using a B-type viscometer.

  The active energy ray-curable inkjet ink composition preferably has a surface tension at 25 ° C. of 20 to 36 mN / m. If the ink surface tension at 25 ° C. is within the above specified range, good ejection stability can be obtained. The ink surface tension can be measured by a plate method.

In addition, the active energy ray-curable inkjet ink composition may be used alone or in combination with a plurality of active energy ray-curable inkjet ink compositions. The cured product of each active energy ray-curable ink-jet ink composition preferably has a difference in near infrared absorption with a wavelength of 0.8 μm to 2.0 μm within a range of 50% or less, and within a range of 30% or less. More preferably, If the difference in near infrared absorption with a wavelength of 0.8 μm to 2.0 μm is 50% or less, even when a multicolor printing layer is formed, variations in the heating rate of the printing layer during the heating process are unlikely to occur. . On the other hand, if the difference in the absorption rate of near-infrared rays with a wavelength of 0.8 μm to 2.0 μm exceeds 50%, the temperature increase rate of the printing layer during the heating process is likely to vary, and the effect of improving adhesion can be obtained uniformly. It may not be possible.
The cured product of the active energy ray-curable inkjet ink composition is obtained by curing the ink composition by a curing process described later. Moreover, although the absorptivity of hardened | cured material can be measured using a spectrophotometer, in this invention, the absorptivity (%) of near infrared rays with a wavelength of 0.8 micrometer-2.0 micrometers is used for every 1 nm using a spectrophotometer. The average of the obtained values was calculated, and the average value was defined as the near infrared absorptivity (%) having a wavelength of 0.8 μm to 2.0 μm.

In the printing method of the present invention, a printing layer is formed on a substrate by printing using one or a plurality of active energy ray-curable inkjet ink compositions. Can be used for Examples of the ink jet printer include an ink jet printer that ejects an ink composition by a charge control method or a piezo method. As the ink jet printer, in particular, a large ink jet printer, specifically, an ink jet printer for printing on an article used in an industrial line can be suitably applied. Moreover, in the printing method of this invention, it is preferable that the discharge amount of the ink composition to a base material is 1-30 g / m < ² >.

  Next, in the printing method of the present invention, a curing step is performed in which the printed layer formed on the substrate by the printing step is cured. Here, since the printing layer is composed of the active energy ray-curable inkjet ink composition, a printing layer with good weather resistance can be formed by irradiating and curing an active energy ray such as ultraviolet rays. it can. Moreover, it is preferable that the wavelength of the active energy ray irradiated for curing the printed layer overlaps with the absorption wavelength of the photopolymerization initiator, and for the active energy ray-curable inkjet ink composition, The dominant wavelength of the active energy ray is preferably 360 to 425 nm. Examples of light sources used for active energy ray irradiation include LEDs, mercury lamps, low-pressure mercury lamps, high-pressure mercury lamps, ultrahigh-pressure mercury lamps, metal halide lamps, and xenon lamps. The active energy ray irradiation conditions are appropriately selected according to the components contained in the ink composition, the ejection amount, and the like, and the irradiation intensity and the integrated light amount may be adjusted as appropriate.

  In the printing method of the present invention, a heating step is then performed in which the printed layer cured in the curing step is heated by near infrared irradiation. As described above, the adhesion of the printing layer to the substrate can be improved by heating the printing layer by irradiation with near infrared rays. Near-infrared rays are highly energy efficient and are expected to reduce environmental impact.

  Near infrared rays generally refer to infrared rays having a wavelength range of 0.7 to 2.5 μm, but near infrared rays irradiated to the printing layer in the heating step of the printing method of the present invention have a dominant wavelength of 0.8 μm to 2. It is preferably 0 μm, and more preferably 0.8 to 1.0 μm. Further, in the radiation spectrum from the light source used for near-infrared irradiation, the amount of spectrum in the wavelength region of 2.0 μm or less is preferably 70% or more, and more preferably 80 to 95%. Thereby, the energy density of near infrared rays becomes very high, and it becomes possible to heat a printing layer more effectively and efficiently. The radiation spectrum can be measured using a spectral radiation measurement device.

  The near-infrared irradiation means is not particularly limited, and a normal near-infrared irradiation device can be used. For example, the main wavelength is 0.8 μm to 2.0 μm and occupies a wavelength region of 2.0 μm or less. In order to emit near-infrared rays having a spectral amount of 70% or more, it is preferable to use a near-infrared irradiation device capable of maintaining the light source in a high temperature state such as 3000 to 3500K. Moreover, a tungsten filament etc. are mentioned as a light source used for near infrared irradiation. In addition, the near-infrared irradiation apparatus can use a commercial item suitably, For example, the NIR emitter etc. by an Adphos company are mentioned.

  In the said heating process, it is preferable that the temperature of the printing layer at the time of a heating process is 100 to 250 degreeC from a viewpoint of heating the adhesiveness of the printing layer with respect to a base material more reliably, and is 150 to 230 degreeC. More preferably. Note that if the temperature of the printed layer is less than 100 ° C., the effect of improving adhesion may not be sufficiently obtained. On the other hand, when it exceeds 250 ° C., the printed layer may be deteriorated and peeled off from the substrate. The temperature of the printed layer can be measured using a non-contact infrared radiation thermometer.

  In the above heating step, the printing layer can be efficiently heated by near-infrared irradiation, so the near-infrared irradiation time may be short, but from the viewpoint of more reliably improving the adhesion of the printing layer to the substrate, the irradiation time is It is preferably 5 to 30 seconds.

  In the printing method of the present invention, the heat-treated print layer can be cooled by a normal cooling means such as an air cooling system.

<Printed matter>
Next, the printed matter of the present invention will be described in detail. The printed matter of the present invention is obtained by the above-described printing method, includes a base material and a printing layer, and has high adhesion to the base material of the printing layer. The thickness of the print layer is not particularly limited, but is, for example, 5 to 15 μm.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

<Example of ink preparation>
A mixture according to the formulation shown in Table 1 was obtained, and this was kneaded with a bead mill to homogenize to prepare inks 1 to 3. In addition, according to the following method, the viscosity and surface tension of each ink composition were measured, and the ejection stability was evaluated. Moreover, the near-infrared absorption factor of wavelength 0.8micrometer-2.0micrometer was calculated | required about the cured | curing material of each ink. The results are shown in Table 1.

(viscosity)
The ink viscosity at 40 ° C. was measured using a B-type viscometer.
(surface tension)
The ink surface tension at 25 ° C. was measured by the plate method.

(Discharge stability)
An image was printed on a substrate by an ink jet printer using the active energy ray curable ink jet ink composition, and the ejection stability was visually evaluated according to the following criteria. Note that printing was performed by setting the distance from the print head of the ink jet printer to the substrate to 1.5 mm.
○: An image can be printed at a predetermined position without causing nozzle clogging.
Δ: No nozzle clogging occurs, but slight flight bending occurs.
X: Nozzle clogging occurs, the image is missing, and the ink cannot adhere to a predetermined position, so that a beautiful image cannot be printed.

(Near-infrared absorptance of wavelength 0.8 μm to 2.0 μm)
An image of 3 × 3 cm is printed on a substrate by an ink jet printer using an active energy ray curable ink jet ink composition, and then an ultraviolet ray is converted into an image under an irradiation condition of 300 mJ / cm ² using an LED lamp having a main wavelength of 385 nm. It was directly irradiated and cured to produce a 10 μm thick printed layer.
Next, the absorption rate of near infrared rays having a wavelength of 0.8 μm to 2.0 μm was determined for the printed layer after curing using a spectrophotometer (UV-3100PC manufactured by Shimadzu Corporation).

a) Pigment dispersant (by Big Chemie Japan)
b) Heliogen Blue L7080 (BASF)
c) SicoFast Red 3855 (BASF)
d) Raven 450 (Colombian Carbon Japan)
e) Silicone surface conditioner (Shin-Etsu Silicone)
f) 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (manufactured by BASF Japan)

<Printing process>
In Examples 1 to 3 and Comparative Examples 1 to 5, inks 1 to 3 were set in an ink jet printer according to Tables 2 to 4, and the ink was ejected onto a stainless steel substrate at 10 g / m ^{2 to} obtain a 3 × 3 cm image. (Printing layer) was created.
In Examples 4 to 6, inks 1 to 3 were set in an ink jet printer according to Table 2, and the ink was ejected onto a stainless steel substrate at 10 g / m ² to print a 3 × 3 cm image with each ink. A printed layer in which the images of FIGS.

<Curing process>
After printing, an LED lamp having a main wavelength of 385 nm was used to directly irradiate the image with ultraviolet rays under irradiation conditions of 300 mJ / cm ² to cure the image.

<Heating process>
In Examples 1 to 6, after curing, using a NIR emitter manufactured by Adphos as a near-infrared irradiator, the near-infrared rays having the main wavelengths and spectral amounts shown in Table 2 were irradiated for the time shown in Table 2 to heat the printed layer. Thus, a printed material having a printed layer having a thickness of 10 μm was produced. The temperature of the printed layer when the heating step was completed was measured. The results are shown in Table 2. In Table 2, Examples 4 to 6 show the temperatures of the portions formed by the respective inks in the printing layer.
In Comparative Examples 1 and 2, after curing, using a hot air dryer as a heating device, the printed layer was heated for the time shown in Table 3 to produce a printed matter having a 10 μm thick printed layer. The temperature of the printed layer when the heating step was completed was measured. The results are shown in Table 3. In addition, the preset temperature of the dryer was set to 200 ° C.
In Comparative Examples 3 and 4, after curing, using a ceramic ceramic plate heater PLC manufactured by Noritake Co., Ltd. as a far infrared irradiator, far infrared rays were irradiated for the time shown in Table 4 to heat the printed layer, and the thickness A printed matter having a 10 μm printed layer was produced. The temperature of the printed layer when the heating step was completed was measured. The results are shown in Table 4.

  Next, with respect to the obtained Examples 1 to 6 and Comparative Examples 1 to 4, the appearance and adhesion of the printed layer were evaluated by the following methods. The results are shown in Tables 2-4.

(Appearance of printed layer)
The presence or absence of blistering was confirmed visually.

(Adhesiveness)
The printed layer was subjected to a cross cut of 1 mm in width and 100 squares, the cellophane tape was sufficiently adhered, and the cellophane tape was peeled off. Adhesion was evaluated according to the following criteria. In addition, adhesiveness was similarly evaluated about the printing layer (thickness 8 micrometers) of the printed matter (comparative example 5) which did not perform the heating process after a printing process and a hardening process (Table 4).
(Double-circle): Peeling is not confirmed in a cut part. (100/100)
○: Peeling of less than 10% can be confirmed at the cut part. (91-99 / 100)
Δ: A part of the cut portion remained, but 10% or more of the peeled portion was recognized. (1-90 / 100)
X: Peeling can be confirmed on the entire cut surface. (0/100)
The numbers in parentheses indicate the number of cells remaining on the substrate when the cellophane tape is peeled off.

Claims (5)

A printing step of forming a printing layer on a substrate by printing using one or more kinds of active energy ray-curable inkjet ink compositions;
A curing step for curing the printed layer formed on the substrate;
The cured printing layer saw including a heating step of heating by irradiation of near infrared rays,
The active energy ray-curable inkjet ink composition includes a pigment, a radical polymerizable monomer having 1 to 2 functional groups, a polyfunctional monomer, and a photopolymerization initiator,
The radical polymerizable monomer having 1 functional group is stearyl acrylate, acryloylmorpholine, tridecyl acrylate, lauryl acrylate, N, N-dimethylacrylamide, decyl acrylate, phenoxyethyl acrylate, isodecyl acrylate, isobornyl acrylate, dicyclohexane. Pentanyl acrylate, dicyclopentenyl acrylate, isooctyl acrylate, octyl acrylate, dicyclopentenyloxyethyl acrylate, cyclohexyl acrylate, isoamyl acrylate, 2-ethylhexyl-diglycol acrylate, EO (ethylene oxide) modified 2-ethylhexyl acrylate, neopentyl glycol Acrylic acid benzoate, N-vinyl-2-pyrrolidone, N- From nilimidazole, tetrahydrofurfuryl acrylate, methoxydipropylene glycol acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, cyclic trimethylolpropane formal acrylate, and ethoxy-diethylene glycol acrylate One or more selected from the group consisting of:
The radical polymerizable monomer having 2 functional groups is 1,10-decanediol diacrylate, 2-methyl-1,8-octanediol diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate. 1,9-nonanediol diacrylate, 1,8-octanediol diacrylate, 1,7-heptanediol diacrylate, polytetramethylene glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1, 6-hexanediol diacrylate, neopentyl glycol diacrylate, neopentyl glycol diacrylate hydroxypivalate, tripropylene glycol diacrylate, 1,4-butanediol diacrylate, and dipropylene glycol diacrylate And the one or more selected from the group consisting of,
Multifunctional monomers include trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated glycerin triacrylate, tetramethylol methane triacrylate, pentaerythritol tetraacrylate, ethoxy Pentaerythritol tetraacrylate, EO-modified diglycerin tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are one or more selected from the group consisting of,
A printing method characterized by the above.   2. The printing method according to claim 1, wherein the near-infrared dominant wavelength irradiated to the print layer is 0.8 μm to 2.0 μm.   The printing method according to claim 1 or 2, wherein in the heating step, the temperature of the printing layer is 100C to 250C. In the printing step, when a plurality of types of active energy ray-curable ink-jet ink compositions are used, the cured product of each active energy ray-curable ink-jet ink composition has a near-infrared absorptance with a wavelength of 0.8 μm to 2.0 μm. The printing method according to claim 3 , wherein the difference is within a range of 50% or less. A printing step of forming a printing layer on a substrate by printing using one or more kinds of active energy ray-curable inkjet ink compositions;
A curing step for curing the printed layer formed on the substrate;
The cured printing layer saw including a heating step of heating by irradiation of near infrared rays,
The active energy ray-curable inkjet ink composition includes a pigment, a radical polymerizable monomer having 1 to 2 functional groups, a polyfunctional monomer, and a photopolymerization initiator,
The radical polymerizable monomer having 1 functional group is stearyl acrylate, acryloylmorpholine, tridecyl acrylate, lauryl acrylate, N, N-dimethylacrylamide, decyl acrylate, phenoxyethyl acrylate, isodecyl acrylate, isobornyl acrylate, dicyclohexane. Pentanyl acrylate, dicyclopentenyl acrylate, isooctyl acrylate, octyl acrylate, dicyclopentenyloxyethyl acrylate, cyclohexyl acrylate, isoamyl acrylate, 2-ethylhexyl-diglycol acrylate, EO (ethylene oxide) modified 2-ethylhexyl acrylate, neopentyl glycol Acrylic acid benzoate, N-vinyl-2-pyrrolidone, N- From nilimidazole, tetrahydrofurfuryl acrylate, methoxydipropylene glycol acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, cyclic trimethylolpropane formal acrylate, and ethoxy-diethylene glycol acrylate One or more selected from the group consisting of:
The radical polymerizable monomer having 2 functional groups is 1,10-decanediol diacrylate, 2-methyl-1,8-octanediol diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate. 1,9-nonanediol diacrylate, 1,8-octanediol diacrylate, 1,7-heptanediol diacrylate, polytetramethylene glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1, 6-hexanediol diacrylate, neopentyl glycol diacrylate, neopentyl glycol diacrylate hydroxypivalate, tripropylene glycol diacrylate, 1,4-butanediol diacrylate, and dipropylene glycol diacrylate And the one or more selected from the group consisting of,
Multifunctional monomers include trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated glycerin triacrylate, tetramethylol methane triacrylate, pentaerythritol tetraacrylate, ethoxy Pentaerythritol tetraacrylate, EO-modified diglycerin tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are one or more selected from the group consisting of,
A method for producing a printed matter.