JP2013040280A - Polymerizable inkjet ink composition, ink cartridge containing the ink composition, and inkjet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-viscosity polymerizable inkjet ink composition which improves curable inkjet ink, having no problem on skin sensitization, excellent curability, and excellent storage stability.SOLUTION: The polymerizable inkjet ink composition contains at least a polymerizable monomer, wherein the polymerizable monomer is a (meth)acrylic acid ester compound or (meth)acrylamide compound, and a vinyl ether compound, and additionally contains water or a tertiary amine compound.

Description

  The present invention relates to a polymerizable inkjet ink composition, an ink cartridge containing the ink composition, and an inkjet printer.

  In the field of ink jet printing, particularly in the field of industrial ink jet printing, curable ink jet inks are spreading from the viewpoints of quick drying, a wide range of substrate choices for printing, and VOC free.

The curable inkjet ink contains, for example, an unsaturated organic compound that is polymerized by electron beam irradiation or by irradiation with ultraviolet light in the presence of a photopolymerization initiator. The curable inkjet ink generates radicals when irradiated with energy, and the unsaturated organic compound is polymerized by radical reaction due to the radicals, and is cured or solidified and fixed. Since this reaction proceeds instantaneously after energy irradiation, it has a property of quick drying.
In addition, curable ink-jet inks solidify instantaneously, so they can be printed on non-ink-absorbing substrates that do not absorb ink, such as metal, glass, ceramics, and plastic films, without deterioration in image quality. There are many types of substrate materials that can be used.
Furthermore, since the whole unsaturated organic compound is polymerized, it gives VOC-free characteristics after curing.

  As an unsaturated organic compound (hereinafter sometimes referred to as a monomer) of a curable inkjet ink, a (meth) acrylic acid ester compound is generally used, but many (meth) acrylic acid ester compounds are viscous. In particular, an ink using a polyfunctional (meth) acrylic acid ester compound having a large number of polymerizable functional groups can form a tough image with a high crosslink density, while being easy to form a highly viscous ink composition. It is difficult to achieve both lowering the viscosity and improving ink curability.

  In response to these problems, JP 2010-509426 A discloses a monomer having an epoxy group that is cured by a cation, a cationic photoinitiator, and water, thereby preventing curing inhibition due to oxygen. In addition, a curable ink jet composition that has improved adhesion is disclosed.

Japanese Patent Application Publication No. 2008-507598 of Patent Document 2 discloses an ethylenically unsaturated monofunctional monomer, an ethylenic difunctional unsaturated monomer, an ethylenically unsaturated polyfunctional monomer, and an ethylenically unsaturated group. By setting the content of each of the urethane oligomers in a specific range, the curing speed is increased, and an ink that is said to have a high resolution even when printing at high speed is disclosed.

  Japanese Patent Application Laid-Open No. 2009-272609 of Patent Document 3 discloses a compound having a methacryloyl group or an acroyl group, a compound having a thermosetting functional group such as a hydroxyl group or a carboxyl group, vinyl ether, which is said to prevent nozzle clogging due to ink curing. Curable compositions containing diluents such as ethylene derivatives.

  Japanese Patent Application Publication No. 2010-530922 of Patent Document 4 discloses that polypropylene or non-porous and low surface tension is added by including a monoacrylate having a glass transition temperature (Tg) that improves the flexibility of the ink layer. A UV curable ink is disclosed which has improved adhesion to the substrate.

  Japanese Patent Application Laid-Open No. 2007-231230 of Patent Document 5, Japanese Patent Application Laid-Open No. 2007-231232 of Patent Document 6, and Japanese Patent Application Laid-Open No. 2008-68516 of Patent Document 7 include esters or amides of (meth) acrylic acid, or carbonization. An ink composition containing a vinyl ether having a hydrogen group and a polymerization initiator and having improved adhesion between the recording medium and the ink is described.

  In Japanese Patent No. 3672651 of Patent Document 8, the amount ratio of (meth) acrylate compound, vinyl ether compound, and photopolymerization initiator is within a specific range, and a paper or plastic group is formed without forming an adhesive resin layer. An ultraviolet curable resin composition for an ink jet recording system capable of forming an image on a material is disclosed.

  Japanese Patent Application Laid-Open No. 2009-62541 of Patent Document 9, Japanese Patent Application Laid-Open No. 2005-532445 of Patent Document 10, and Japanese Patent Application Laid-Open No. 2004-526820 of Patent Document 11 include α, β-unsaturated ethers as (meth) acrylates. It is disclosed that an ink having a high curing speed and a low viscosity can be obtained by using with a monomer.

In addition, (meth) acrylic acid ester compounds are toxic for skin sensitization (a delayed hypersensitivity reaction that causes skin irritation caused by an excessive immune reaction due to chemical substances) that causes allergy when touched to the skin. If an uncured monomer component remains in the printed matter, it may cause allergies when touched with fingers or the like, and an ink that can form a safe printed matter that does not cause allergies is desired.
However, as described above, in addition to the difficulty itself in achieving both low viscosity and improved curability of the curable inkjet ink, there is no problem of skin sensitization or skin sensitization. It is very difficult to obtain a curable ink-jet ink with less problems, and those described in the above-mentioned patent documents have not been considered for skin sensitization.

  The inventors of the present invention previously described in Japanese Patent Application No. 2011-107318 of Patent Document 12 contain a (meth) acrylate compound and / or a (meth) acrylamide compound and vinyl ether, and have a problem of skin sensitization. However, the present invention discloses a photopolymerizable inkjet ink having excellent curability and low viscosity. However, it was subsequently found that the polymerizable inkjet ink has insufficient storage stability.

  Therefore, the present invention improves the curable inkjet ink described in Japanese Patent Application No. 2011-107318, has excellent curability and storage stability, has a low viscosity, and has a skin feel as needed. An object of the present invention is to provide a polymerizable inkjet ink that can solve the problem of workability.

The present inventors have made extensive studies to improve the storage stability of the polymerizable inkjet ink, and have been widely used as a polymerization initiator for a photopolymerizable inkjet ink containing a (meth) acrylate compound. Even when typical phenol / quinone compounds such as hydroquinone and methoquinone, which are general polymerization inhibitors, were added, sufficient storage stability could not be obtained.
However, it has been found that the storage stability of the polymerizable inkjet ink can be improved by containing water or a tertiary amine compound instead of or in addition to these polymerization inhibitors.
This invention is made | formed based on the knowledge which concerns, The said subject is solved by following (1)-(9) of this invention.
(1) “A polymerizable inkjet ink composition containing at least a polymerizable monomer, wherein the polymerizable monomer is a (meth) acrylic acid ester compound or a (meth) acrylamide compound, and a vinyl ether compound, A polymerizable inkjet ink composition comprising water or a tertiary amine compound ",
(2) The polymerizable inkjet ink according to item (1), wherein the (meth) acrylic acid ester compound or (meth) acrylamide compound contains a polyfunctional compound having 1 to 6 functional groups. Composition",
(3) "The polymerizable inkjet ink composition according to (1) or (2) above, further comprising a photoradical polymerization initiator",
(4) “The Stimulation Index (SI value) indicating the degree of sensitization in the skin sensitization test (LLNA method) of the polymerizable monomer used in the polymerizable inkjet ink composition is less than 3. The polymerizable inkjet ink composition according to any one of (1) to (3),
(5) "The polymerizable inkjet ink composition according to any one of (1) to (4), wherein the vinyl ether compound is triethylene glycol divinyl ether";
(6) "The polymerizable inkjet ink composition according to any one of (1) to (5) above, wherein water is dissolved in the ink material",
(7) The above-mentioned tertiary amine compound is an ethanolamine having a tertiary amine structure, an aromatic tertiary amine compound, or a polymer material having a tertiary amino group. The polymerizable ink-jet ink composition according to any one of items 1) to (5) ", (8) The photopolymerizable ink-jet ink according to any one of items (1) to (7). An ink cartridge comprising a composition ",
(9) “A polymerizable inkjet ink composition according to any one of (1) to (7), or a printing unit and a radiation source irradiation unit,” or “(8)”. Inkjet printer with an ink cartridge. "

  As will be understood from the following detailed and specific description, according to the present invention, a low-viscosity polymerizable inkjet ink having no skin sensitization problem, excellent curability, and excellent storage stability is obtained. Can be provided.

FIG. 3 is a schematic diagram illustrating an example of an ink bag of an ink cartridge. FIG. 3 is a schematic diagram illustrating an example of an ink cartridge that houses an ink bag. It is the schematic which shows an example of an inkjet recording device (printing apparatus).

The polymerizable inkjet ink of the present invention will be described in detail.
The polymerizable inkjet ink composition of the present invention contains at least a polymerizable monomer, and the polymerizable monomer is a (meth) acrylic acid ester compound or a (meth) acrylamide compound and a vinyl ether compound, and water or 3 Contains a secondary amine compound.

As the (meth) acrylic acid ester compound or (meth) acrylamide compound, conventionally known compounds can be used, but those having an SI value of less than 3 indicating the degree of sensitization in the skin sensitization test by the LLNA method Is preferred.
Here, the skin sensitization test LLNA method is a skin sensitization test defined as the OECD test guideline 429. For example, “Functional Materials” September 2005, Vol. 25, no. 9, P55), when the Stimulation Index (SI value) indicating the degree of skin sensitization is less than 3, it is determined that there is no problem with skin sensitization. In addition, since those whose skin sensitivity is described as “None” or “Negative” in the Material Safety Data Sheet (MSDS) naturally satisfy the SI value of less than 3, these are uniformly defined. It can be considered that there is no problem with the skin sensitivity.

  In the polymerizable inkjet ink composition of the present invention, the SI value of the polymerizable monomer is preferably 3 or less, whereby a polymerizable inkjet ink that is safe in skin sensitization can be obtained. Even if an uncured monomer component remains, it is safe in terms of skin sensitization, and a safe printed matter that does not cause skin sensitization even when touched with a finger or the like can be provided.

  Examples of (meth) acrylic acid ester compounds or (meth) acrylamide compounds that have no problem of skin sensitization and can be easily procured include polyethylene glycol dimethacrylate represented by the following formula (1),

（但しｎ≒９〜１４）
γ−ブチロラクトンメタクリレート、トリメチロールプロパントリメタクリレート、トリシクロデカンジメタノールジメタクリレート、カプロラクトン変性ジペンタエリスリトールヘキサアクリレート、
下記式（２）で示されるポリプロピレングリコールジアクリレート、

(However, n≈9-14)
γ-butyrolactone methacrylate, trimethylolpropane trimethacrylate, tricyclodecane dimethanol dimethacrylate, caprolactone-modified dipentaerythritol hexaacrylate,
Polypropylene glycol diacrylate represented by the following formula (2):

（但しｎ≒１２）
カプロラクトン変性ヒドロキシピバリン酸ネオペンチルグリコールエステルのジアクリレート、ポリエトキシ化テトラメチロールメタンテトラアクリレート、エチレンオキサイド変性ビスフェノールＡジアクリレート、ネオペンチルグリコールジメタクリレート、ステアリルアクリレート、１，４−ブタンジオールジメタクリレート、ヒドロキシエチルアクリルアミド等が挙げられる。

(However, n ≒ 12)
Caprolactone-modified hydroxypivalic acid neopentyl glycol ester diacrylate, polyethoxylated tetramethylol methane tetraacrylate, ethylene oxide modified bisphenol A diacrylate, neopentyl glycol dimethacrylate, stearyl acrylate, 1,4-butanediol dimethacrylate, hydroxyethylacrylamide Etc.

In addition, although there is some problem in skin sensitization by itself, the following (meth) acrylates and (meth) acrylamides can be used in combination as long as no problem occurs as an ink.
Examples of (meth) acrylates that can be used in combination with (meth) acrylates and (meth) acrylamides that do not have the problem of skin sensitization, and (meth) acrylamides include, for example, ethylene glycol di (meth) acrylates and hydroxypivalate neopentyl glycol di (Meth) acrylate, γ-butyrolactone acrylate, isobornyl (meth) acrylate, formalized trimethylolpropane mono (meth) acrylate, polytetramethylene glycol di (meth) acrylate, trimethylolpropane (meth) acrylic acid benzoate, diethylene glycol Di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol diacrylate [C _{2 = CH-CO- (OC 2} H 4) n-OCOCH = CH 2 (n = 4) ], the (n = 9), the (n = 14), the (n = 23)], dipropylene glycol Di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol dimethacrylate [CH ₂ ═C (CH ₃ ) —CO— (OC ₃ H ₆ ) n—OCOC (CH ₃ ) ═CH ₂ (n = 7)], 1,3-butanediol di (meth) acrylate, 1,4-butanediol diacrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, Di (meth) acrylate of neopentyl glycol di (meth) acrylate, tricyclodecane dimethanol diacrylate, bisphenol A propylene oxide adduct ) Acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, methacryloylmorpholine, 2-hydroxyethyl (meth) acrylamide, ethylene oxide modified tetramethylol Methanetetra (meth) acrylate, dipentaerythritol hydroxypenta (meth) acrylate, caprolactone-modified dipentaerythritol hydroxypenta (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropanetri Acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, propylene Side-modified trimethylolpropane tri (meth) acrylate, caprolactone-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, neopentyl glycol diacrylate , Ethoxylated neopentyl glycol di (meth) acrylate, propoxylated neopentyl glycol di (meth) acrylate, propoxylated glyceryl tri (meth) acrylate, polyester di (meth) acrylate, polyester tri (meth) acrylate, polyester tetra (meth) ) Acrylate, polyester penta (meth) acrylate, polyester poly (meth) acrylate, vinyl caprolactam, vinyl pyro Examples include redone, N-vinylformamide, polyurethane di (meth) acrylate, polyurethane tri (meth) acrylate, polyurethane tetra (meth) acrylate, polyurethane penta (meth) acrylate, polyurethane hexa (meth) acrylate, and the like.

Examples of the vinyl ether compound having no problem of skin sensitization include triethylene glycol divinyl ether. Since this vinyl ether compound has a low viscosity, it is possible to achieve a reduction in viscosity and an improvement in curability while maintaining the characteristics that do not cause a problem in skin sensitization, compared with the case where no vinyl ether compound is used in combination.

However, as described later, it is preferable to use a photo-radical polymerization initiator in the ink of the present invention, and vinyl ether itself is not so high in radical polymerization reactivity. If the vinyl ether compound is added excessively, the viscosity can be reduced, but the curability may be greatly impaired. Therefore, the content of the vinyl ether compound is preferably 5% by weight or more and 60% by weight or less, more preferably 30% by weight or more and 50% by weight or less in the polymerizable monomer, from the balance between low viscosity and curability. is there.

The polymerizable inkjet ink of the present invention contains water or a tertiary amine compound.
The water content depends on the (meth) acrylic acid ester compound or (meth) acrylamide compound to be used, but from the balance of curing speed and storage stability after energy irradiation, with respect to 100 parts by weight of the polymerizable monomer, It is preferably 0.1 parts by weight or more and 3 parts by weight or less, and more preferably 0.5 parts by weight or more and 1.5 parts by weight.
In addition, since the polymerizable monomer having an SI value of less than 3 is not necessarily highly hydrophilic, the amount of water added is within the range in which the polymerizable monomer is dissolved and uniform, thereby making the ink uniform. In addition, it is possible to avoid problems of fluidity in the ink flow path and ink-jet discharge properties associated with separation and precipitation of the ink composition.
In the present invention, whether or not it was dissolved was visually confirmed in a state in which it was uniformly transparent in a state in which no coloring material such as a pigment was included.

  The content of the tertiary amine compound depends on the (meth) acrylic acid ester compound or (meth) acrylamide compound to be used, but from the balance between the curing rate after energy irradiation and the storage stability, the content is 100 parts by weight of the polymerizable monomer. On the other hand, it is preferably 0.01 parts by weight or more and 10 parts by weight or less, and more preferably 0.1 parts by weight or more and 5 parts by weight or less.

As the tertiary amine compound, ethanolamine having a tertiary amine structure, an aromatic tertiary amine compound, and a polymer material having a tertiary amino group can be used, and the aromatic tertiary amine compound is a radical polymerization. A polymer compound having a function as an accelerator and a tertiary amino group can be preferably used because it also has a function as a pigment dispersant.
These tertiary amine compounds may be used alone or in combination of two or more.

The ethanolamine having a tertiary amine structure is preferably N-methyldiethanolamine.
Examples of the aromatic tertiary amine compound include ethyl p-dimethylaminobenzoate, p-dimethylaminobenzoic acid-2-ethylhexyl, methyl p-dimethylaminobenzoate, benzoic acid-2-dimethylaminoethyl, p-dimethylamino. Preferably, it is butoxyethyl benzoate.
As the polymer material having a tertiary amino group, a material in which the main skeleton is polyester or polyurethane is preferable.
As the polymer material having the tertiary amino group, commercially available products such as Nippon Lubrizol Solsperse, Enomoto Kasei Disparon, and Ajinomoto Finetech Ajisper, which are commercially available as polymer pigment dispersants, can be used.

As the polymerization initiator, a radical photopolymerization initiator or a cationic photopolymerization initiator can be used, but it is necessary to be a radical photopolymerization initiator.
The reason is as follows. (Meth) acrylic acid ester compounds generally have not only radical polymerizability but also cationic polymerizability, but photocationic polymerization initiators are generally not only expensive, but also are not subject to light irradiation. Since a strong acid is gradually generated, selection of members in contact with ink such as an ink supply path in a printer is restricted, and UVLEDs that are attracting attention as an energy-saving curing light source in recent years are currently in practical use. Although there is only a thing of 365 nm or a longer wavelength as a thing, there exists a problem that there is not what has sufficient sensitivity in such a long wavelength region.

Examples of the photo radical polymerization initiator include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane-1- ON, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy- 2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-1-propan-1-one, phenylglyoxyc acid methyl ester, 2-methyl-1- [4- (methylthio) phenyl] -2- Morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-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-phosphine oxide, 1,2-octanedione- [4- (phenylthio) -2- (O-benzoyloxime)], [ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime)], [4- ( Methylphenylthio) phenyl] phenylmethanone, benzophenone, methylbenzophenone, methyl-2-benzoylbenzoate, 4-ben Yl-4'-methyl diphenyl sulfide, phenyl, 2,4-diethyl thioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, and 1-chloro-4-propyl thioxanthone and the like.
The content of the polymerization initiator is preferably 1 to 20 parts by weight with respect to 100 parts by weight of the polymerizable monomer.

The polymerizable inkjet ink of the present invention can contain a polymerization inhibitor.
Examples of the polymerization inhibitor include 4-methoxy-1-naphthol, methylhydroquinone, hydroquinone, t-butylhydroquinone, methoquinone, di-t-butylhydroquinone, 2,2′-dihydroxy-3,3′-di (α -Methylcyclohexyl) -5,5'-dimethyldiphenylmethane, p-benzoquinone, 9,10-di-n-butoxycyantracene, 4,4 '-[1,10-dioxo-1,10-decandiylbis (oxy)] Examples thereof include radical polymerization inhibitors that have been conventionally used, such as bis [2,2,6,6-tetramethyl] -1-piperidinyloxy.

The polymerizable inkjet ink of the present invention may contain a colorant, and a known inorganic pigment or organic pigment can be used as the colorant.
As the black pigment, for example, carbon black produced by a furnace method or a channel method can be used.
Examples of white pigments include sulfates of alkaline earth metals such as barium sulfate, alkaline earth metal carbonates such as calcium carbonate, silicas such as finely divided silicate and synthetic silicate, calcium silicate, alumina, Alumina hydrate, titanium oxide, zinc oxide, talc, clay and the like can be used.
Examples of yellow pigments include Pig. Yellow pigments such as Pigment Yellow 1, Pigment Yellow 2, Pigment Yellow 3, Pigment Yellow 12, Pigment Yellow 13, Pigment Yellow 14, Pigment Yellow 16, Pigment Yellow 17, Pigment Yellow 73, Pigment Yellow 74, Pigment Yellow 75, Pigment Yellow 83, Pigment Yellow 93, Pigment Yellow 95, Pigment Yellow 97, Pigment Yellow 98, Pigment Yellow 114, Pigment Yellow 120, Pigment Yellow 128, Pigment Yellow 129, Pigment Yellow 138, Pigment Yellow 150, Pigment Yellow 151, Pigment Yellow 154, Pigment Yellow 155, Pigment Yellow 180, etc. It can be used.
Examples of magenta pigments include Pig. Red pigments such as Pigment Red 5, Pigment Red 7, Pigment Red 12, Pigment Red 48 (Ca), Pigment Red 48 (Mn), Pigment Red 57 (Ca), Pigment Red 57: 1, Pigment Red 112, Pigment Red 122, pigment red 123, pigment red 168, pigment red 184, pigment red 202, pigment violet 19, and the like can be used.
Examples of cyan pigments include Pig. Blue pigments such as Pigment Blue 1, Pigment Blue 2, Pigment Blue 3, Pigment Blue 15, Pigment Blue 15: 3, Pigment Blue 15: 4, Pigment Blue 16, Pigment Blue 22, Pigment Blue 60, Bat Blue 4, Bat Blue 60 or the like can be used.
In addition, various inorganic pigments and organic pigments can be used in consideration of physical characteristics as required.

The polymerizable ink of the present invention preferably has a viscosity at 25 ° C. of 3 to 200 mPa · s. For example, in GEN4 manufactured by Ricoh Printing Systems as a commercially available inkjet discharge head, it can be heated to 60 ° C., Since discharge is possible at 20 mPa · s or less, this is not the case as long as the viscosity is sufficiently lowered by heating.

  The ink of the present invention can be stored in a container and used as an ink cartridge. Accordingly, it is not necessary to directly touch the ink in operations such as ink replacement, there is no concern about dirt on fingers and clothes, and foreign matters such as dust can be prevented from being mixed into the ink.

  The container is not particularly limited, and its shape, structure, size, material and the like can be selected as appropriate according to the purpose. A thing etc. are mentioned suitably.

  The ink cartridge will be described with reference to FIGS. Here, FIG. 1 is a schematic view showing an example of the ink bag (241) of the ink cartridge of the present invention, and FIG. 2 is an ink cartridge in which the ink bag (241) of FIG. 1 is accommodated in a cartridge case (244). It is the schematic which shows (200).

As shown in FIG. 1, after filling the ink bag (241) with ink from the ink inlet (242) and exhausting the air remaining in the ink bag, the ink inlet (242) is fused. close up. In use, the needle of the apparatus main body is inserted into the ink discharge port (243) made of a rubber member and supplied to the apparatus. The ink bag (241) is formed of a packaging member such as a non-permeable aluminum laminate film.
As shown in FIG. 2, it is usually housed in a plastic cartridge case (244) and used as an ink cartridge (200) detachably attached to various ink jet recording apparatuses.

  The ink cartridge of the present invention is particularly preferably used by being detachably mounted on the ink jet recording apparatus of the present invention described later. Thereby, replenishment and replacement of ink can be simplified and workability can be improved.

An example of the ink jet recording apparatus (printing apparatus) according to the present invention is shown in the schematic diagram of FIG. Note that the form and configuration of the printing apparatus are not limited by this example.
In the configuration of FIG. 3, each of the printing units (3) [consisting of printing units 3 a, 3 b, 3 c, 3 d for each color (for example, yellow, magenta, cyan, black)] has a printing substrate supply roll (1). UV light source (curing light source) (4a, 4b) for each color (yellow, magenta, cyan, black) ejected onto the substrate to be printed (2) (conveyed from left to right in the figure) supplied from 4c, 4d) is cured by irradiation with light (UV light) to form a color image.

  The printing units (3a, 3b, 3c, 3d) may be provided with a mechanism for heating the ink discharge portion to reduce the viscosity of the ink as necessary. For various processing after printing, a processing unit (5) may be provided to perform processing such as perforations, marginal punches, file holes, and corner cuts as necessary.

As the substrate to be printed (2), paper, film, metal, or a composite material thereof is used. Moreover, although the to-be-printed base material (2) has shown the case where it is roll shape in FIG. 3, a sheet form may be sufficient. Further, double-sided printing as well as single-sided printing may be used. Higher curability can be obtained by irradiating ultraviolet rays each time each color is printed to increase printing speed. For example, the ultraviolet light sources (4a, 4b, 4c) are weakened or omitted, and a plurality of colors can be obtained. Energy saving and cost reduction can be achieved by irradiating and curing a sufficient amount of ultraviolet rays together (4d) after printing.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

(Comparative Example 1)
The following materials were mixed to obtain an inkjet ink.
Dipentaerythritol penta / hexaacrylate 20 parts by weight (no sensitization data available)
10 parts by weight of trimethylolpropane triacrylate (described as a sensitizing substance in MSDS)
20 parts by weight of propylene oxide-modified neopentyl glycol diacrylate (SI value = 3.7)
10 parts by weight of neopentyl glycol dimethacrylate (SI value = 2.0)
40 parts by weight of triethylene glycol divinyl ether (description of MSDS without sensitization)
Photoradical polymerization initiator 10 parts by weight (2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (sensitivity to MSDS) None)))
Polymerization inhibitor (t-butylhydroquinone) 0.1 parts by weight

Example 1
An inkjet ink was obtained in the same manner as Comparative Example 1 except that 1 part by weight of water was added to the ink of Comparative Example 1.
In addition, it was confirmed visually that the ink of Example 1 was uniformly transparent.

(Example 2)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 1 part by weight of N-methyldiethanolamine.

(Example 3)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 2 parts by weight of N-methyldiethanolamine.

Example 4
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 5 parts by weight of N-methyldiethanolamine.

(Example 5)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 1 part by weight of ethyl p-dimethyl-aminobenzoate.

(Example 6)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 2 parts by weight of ethyl p-dimethyl-aminobenzoate.

(Example 7)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 5 parts by weight of ethyl p-dimethyl-aminobenzoate.

(Example 8)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 1 part by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

Example 9
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 2 parts by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

(Example 10)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 5 parts by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

(Example 11)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced by 1 part by weight of methyl p-dimethyl-aminobenzoate.

(Example 12)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 1 part by weight of ethyl p-dimethyl-aminobenzoate.

(Example 13)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 1 part by weight of butoxyethyl p-dimethyl-aminobenzoate.

(Example 14)
An inkjet ink was obtained in the same manner as in Example 1 except that the water of Example 1 was replaced with 1 part by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 15)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 2 parts by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 16)
An inkjet ink was obtained in the same manner as in Example 1 except that the water in Example 1 was replaced with 5 parts by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 17)
An inkjet ink was obtained in the same manner as in Example 1 except that the water of Example 1 was replaced with 1 part by weight of tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

(Example 18)
An inkjet ink was obtained in the same manner as in Example 1 except that the water of Example 1 was replaced with 2 parts by weight of tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

(Example 19)
An inkjet ink was obtained in the same manner as in Example 1 except that the water of Example 1 was replaced with 5 parts by weight of tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

(Comparative Example 2)
The following materials were mixed to obtain an inkjet ink.
20 parts by weight of caprolactone-modified dipentaerythritol hexaacrylate (description negative to MSDS)
10 parts by weight of ethylene oxide-modified bisphenol A diacrylate (SI value = 1.2)
5 parts by weight of polyethoxylated tetramethylol methane tetraacrylate (SI value = 1.7)
Caprolactone-modified neopentyl glycol dihydroxypivalate diacrylate (SI value = 0.9) 5 parts by weight hydroxyethyl acrylamide 2 parts by weight (denoted MSDS non-sensitizing)
Polypropylene glycol (n≈12) diacrylate 5 parts by weight (SI value = 1.5)
Polyethylene glycol (n≈14) dimethacrylate 1 part by weight (SI value = 1.6)
Polyethylene glycol (n≈9) dimethacrylate 1 part by weight (SI value = 1.3)
2 parts by weight of trimethylolpropane trimethacrylate (SI value = 1.9)
1 part by weight of γ-butyrolactone methacrylate (SI value = 2.1)
Stearyl acrylate 2 parts by weight (2.7)
Neopentyl glycol dimethacrylate 2 parts by weight (SI value = 2.0)
1,4, -butanediol dimethacrylate 2 parts by weight (SI value = 2.6)
2 parts by weight of tricyclodecane dimethanol dimethacrylate (SI value = 1.3)
40 parts by weight of triethylene glycol divinyl ether (Description of MSDS without sensitization)
Photoradical polymerization initiator 10 parts by weight (2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (sensitivity to MSDS) None)))

Polymerization inhibitor (t-butylhydroquinone) 0.1 parts by weight

(Example 20)
An inkjet ink was obtained in the same manner as in Comparative Example 2 except that 1 part by weight of water was added to the ink of Comparative Example 2.
In addition, it was confirmed visually that the ink of Example 20 was uniformly transparent.

(Example 21)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 1 part by weight of N-methyldiethanolamine.

(Example 22)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 2 parts by weight of N-methyldiethanolamine.

(Example 23)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 5 parts by weight of N-methyldiethanolamine.

(Example 24)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 1 part by weight of ethyl p-dimethyl-aminobenzoate.

(Example 25)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 2 parts by weight of ethyl p-dimethyl-aminobenzoate.

(Example 26)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 5 parts by weight of ethyl p-dimethyl-aminobenzoate.

(Example 27)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 1 part by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

(Example 28)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 2 parts by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

(Example 29)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 5 parts by weight of p-dimethyl-aminobenzoic acid (2-ethylhexyl).

(Example 30)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 1 part by weight of methyl p-dimethylaminobenzoate.

(Example 31)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 1 part by weight of ethyl p-dimethyl-aminobenzoate.

(Example 32)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 1 part by weight of butoxyethyl p-dimethyl-aminobenzoate.

(Example 33)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 1 part by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 34)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 2 parts by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 35)
An inkjet ink was obtained in the same manner as in Example 20, except that the water of Example 20 was replaced with 5 parts by weight of tertiary amino group-containing polyester (Solsperse 32000 manufactured by Nippon Lubrizol Corporation).

(Example 36)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 1 part by weight of a tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

(Example 37)
An inkjet ink was obtained in the same manner as in Example 20 except that the water in Example 20 was replaced with 2 parts by weight of tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

(Example 38)
An inkjet ink was obtained in the same manner as in Example 20, except that the water in Example 20 was replaced with 5 parts by weight of tertiary amino group-containing polyurethane (Solsperse X300 manufactured by Nippon Lubrizol Corporation).

The above ink was sealed in a sample bottle, heated at 70 ° C. and allowed to stand for 4 days, and the appearance properties were visually confirmed.
The evaluation results are shown in Tables 1 and 2.
○: Good storage stability (holding fluidity similar to the initial state)
×: Storage stability is poor (part or all are gelled (polymerized and solidified))

DESCRIPTION OF SYMBOLS 1 Printed substrate supply roll 2 Printed substrate 3a Each color printing unit 3b Each color printing unit 3c Each color printing unit 3d Each color printing unit 4a Ultraviolet light source 4b Ultraviolet light source 4c Ultraviolet light source 4d Ultraviolet light source 5 Processing unit 6 Print winding Removing roll 200 Ink cartridge 241 Ink bag 242 Ink inlet 243 Ink outlet 244 Cartridge case

Special table 2010-509426 Special table 2008-507598 JP 2009-272609 A Special table 2010-530922 JP 2007-231230 A JP 2007-231232 A JP 2008-68516 A Japanese Patent No. 3672651 JP 2009-62541 A JP 2005-532445 A JP 2004-526820 A Japanese Patent Application No. 2011-107318

Claims (9)

A polymerizable inkjet ink composition comprising at least a polymerizable monomer, wherein the polymerizable monomer is a (meth) acrylic acid ester compound or a (meth) acrylamide compound, and a vinyl ether compound, and further, water or tertiary A polymerizable inkjet ink composition comprising an amine compound. The polymerizable inkjet ink composition according to claim 1, wherein the (meth) acrylic acid ester compound or the (meth) acrylamide compound contains a polyfunctional compound having 1 to 6 functional groups. The polymerizable inkjet ink composition according to claim 1, further comprising a photoradical polymerization initiator. The Stimulation Index (SI value) indicating the degree of sensitization in a skin sensitization test (LLNA method) of a polymerizable monomer used in the polymerizable inkjet ink composition is less than 3. The polymerizable inkjet ink composition according to any one of 1 to 3. The polymerizable inkjet ink composition according to claim 1, wherein the vinyl ether compound is triethylene glycol divinyl ether. The polymerizable inkjet ink composition according to claim 1, wherein water is dissolved in the ink material. 6. The tertiary amine compound according to claim 1, wherein the tertiary amine compound is ethanolamine having a tertiary amine structure, an aromatic tertiary amine compound, or a polymer material having a tertiary amino group. A polymerizable inkjet ink composition according to claim 1.   An ink cartridge comprising the photopolymerizable inkjet ink composition according to any one of claims 1 to 7.   An ink jet printer having a printing unit and a radiation source irradiation unit and equipped with the polymerizable ink jet ink composition according to any one of claims 1 to 7 or the ink cartridge according to claim 8.

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