JP2017019939A - Active energy ray hardening composition, ink, composition storing container, object creating apparatus, object creating method and hardened material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy ray hardening composition having excellent extension of hardening membrane and having excellent rubfastness in a coating film after hardening.SOLUTION: An active energy ray hardening composition contains at least two or more kind of monofunctional polymerizable compound and polyfunctional polymerizable compound. As the polyfunctional polymerizable compound, the active energy ray hardening composition contains a polymerizable compound A in which the number of functional groups is 2 or 3, average molecular weight is 500 or more and 5000 or less and glass transition temperature in a case of independent polymerization is 40°C or more. The content of monofunctional polymerizable compound in the active energy ray hardening composition is 60 mass% or more and 75 mass% or less. The content of polymerizable compound A in the active energy ray hardening composition is 3 mass% or more and 12 mass% or less. A polymerizable compound other than the polymerizable compound A has a composition ratio so that calculation value of glass transition temperature of polymer made of the polymerizable compound other than the polymerizable compound A is 25°C or more in FOX formula.SELECTED DRAWING: None

Description

  The present invention relates to an active energy ray-curable composition, ink, image forming method, and cured product that are excellent in heat stretchability and scratch resistance.

In recent years, photo-curable ink-jet inks have been increasingly demanded to be subjected to a molding process as a post-processing, and there is an increasing demand for a substrate follow-up property at the time of the molding process. As a forming process, a stretching process is often performed, and stretchability is required as an ink cured film. Further, when stretchability is imparted to the ink cured film, there are many problems with the scratch resistance of the ink cured film, which causes printing defects during molding.
In order to solve these problems, studies have been made so far.

  Patent Document 1 discloses an invention related to an ultraviolet curable ink in which a monofunctional acrylic monomer having a Tg of less than 20 ° C. is blended with discharge properties, curability, and flexibility as problems.

  Patent Document 2 discloses an invention in which low Tg and high Tg monomers are used in combination, but it cannot be said that both scratch resistance and stretchability and hardness and stretchability are compatible.

Patent Document 3 relates to an ultraviolet curable ink containing a monofunctional acrylic monomer having a Tg of less than −25 ° C. and a bifunctional oligomer having an elongation of 130% or higher at 25 ° C. The invention is disclosed.
Patent Document 4 discloses a patent containing a resinous oligomer.

  An object of the present invention is to provide an active energy ray-curable composition that is excellent in stretchability of a cured film and has good scratch resistance of a cured coating film.

The present invention relates to an active energy ray-curable composition as described below.
An active energy ray-curable composition comprising at least two or more monofunctional polymerizable compounds and a polyfunctional polymerizable compound, wherein the polyfunctional polymerizable compound has a number average of 2 or 3 functional groups It contains a polymerizable compound A having a molecular weight of 500 or more and 5000 or less and a glass transition temperature of 40 ° C. or more when polymerized alone, and the content of the monofunctional polymerizable compound in the active energy ray-curable composition is It is 60 mass% or more and 75 mass% or less, content of the said polymeric compound A in an active energy ray curable composition is 3 mass% or more and 12 mass% or less, and polymeric compounds other than the said polymeric compound A Is formulated in a ratio such that the calculated value of the glass transition temperature of a polymer composed of a polymerizable compound other than the polymerizable compound A is 25 ° C. or higher in the formula of FOX. Energy ray-curable composition.

  ADVANTAGE OF THE INVENTION According to this invention, the active energy ray-curable composition which can obtain the printed matter which satisfies both abrasion resistance and stretchability can be provided.

It is a figure which shows embodiment of an ink cartridge. It is a figure which shows embodiment of the image forming apparatus provided with the inkjet discharge means. It is a figure which shows an example of the image forming apparatus of this invention. It is a figure which shows another example of the image forming apparatus of this invention.

Hereinafter, embodiments for carrying out the present invention will be described in detail.
In addition, this invention is not restrict | limited to the following embodiment, A various deformation | transformation can be implemented within the range of the summary.

In this specification, “stretchability” can be translated into elongation of the cured film (coating film) of the active energy ray-curable composition, and is composed of a cured film prepared by curing the active energy ray-curable composition coating film. When a recorded material is pulled, it means a property that the cured film extends without causing cracks.
In addition, “scratch resistance” can be translated into toughness of a cured film (coating film) of the active energy ray-curable composition, and on a recorded material produced by curing the coating film of the active energy ray-curable composition. The property that does not cause the cured film to be scraped when rubbed while being loaded.

  In this specification, “(meth) acrylate” means at least one of acrylate and its corresponding methacrylate, and “(meth) acryl” means at least one of acryl and its corresponding methacryl.

[Active energy ray-curable composition]
The active energy ray-curable composition according to one embodiment of the present invention contains at least the following components.
・ Monofunctional polymerizable compounds
Polymerizable compound A
-Photoinitiator Hereinafter, the additive (component) which is contained in the active energy ray curable composition of this embodiment, or may be contained depending on necessity is demonstrated.
Hereinafter, the “active energy ray-curable composition” may be simply referred to as “ink” or “ink composition”.

[Monofunctional polymerizable compound]
The monofunctional polymerizable compound contained in the active energy ray-curable composition of the present embodiment includes an unsaturated hydrocarbon chain as a reactive functional group, but preferably a vinyl group, an isopropenyl group, an allyl group, a methallyl group. , An acryloyl group, a methacryloyl group, a propioloyl group, and a maleoyl group. In particular, (meth) acrylic acid esters having one (meth) acryloyl group are preferred.
Examples of the monofunctional polymerizable compound include, but are not limited to, the following compounds.
2-ethylhexyl (meth) acrylate (EHA), 2-hydroxyethyl (meth) acrylate (HEA), 2-hydroxypropyl (meth) acrylate (HPA), caprolactone-modified tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate , 3-methoxybutyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylate, caprolactone (meth) acrylate, ethoxylated nonylphenol (meth) ) Acrylate, oxetane (meth) acrylate, silsesoxane (meth) acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, adamant (Meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, 3,3,5-trimethylcyclohexanol acrylate, cyclic trimethylolpropane formal monoacrylate N-vinylformamide, N-vinyl Carbazole, N-vinylacetamide, N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, and derivatives thereof These monofunctional monomers are used in combination of two or more.

  60-75 mass% is preferable with respect to the total mass (100 mass%) of an ink composition, and, as for content in the active energy ray-curable composition of said monofunctional polymerizable compound, 70-75 mass% is more. preferable. By setting the content to 60% by mass or more, the stretchability can be improved. On the other hand, by setting the content to 75% by mass or less, a reduction in scratch resistance can be prevented. Furthermore, by setting it as the range of 70 to 75 mass%, it is possible to further improve the scratch resistance and the stretchability of the cured film.

[Polymerizable compound A]
The polymerizable compound A contained in the ink composition of the present embodiment is a polymerizable compound having 2 or 3 functional groups, has a number average molecular weight of 500 to 5000, and has a glass transition temperature of 40 ° C. when polymerized alone. That's it.

Examples of the reactive functional group include an unsaturated hydrocarbon chain, and preferred are compounds having a vinyl group, an isopropenyl group, an allyl group, a methallyl group, an acryloyl group, a methacryloyl group, a propioyl group, and a maleoyl group. In particular, (meth) acrylic acid esters having a (meth) acryloyl group are preferred.
When the functional group is not included, it is not preferable from the viewpoint of compatibility at the time of curing, and the fastness of the cured product is deteriorated. Moreover, when it has more than 3 functional groups, since the stretchability of hardened | cured material will be reduced, it is unpreferable. By setting the number of functional groups to 3 or less, stretchability and scratch resistance can be further improved.

  The number average molecular weight of the polymerizable compound A is 500 or more and 5000 or less, preferably 1000 to 2000. By setting the number average molecular weight to 500 or more, the scratch resistance can be improved, and by setting the number average molecular weight to 5000 or less, a decrease in stretchability can be prevented. Further, by setting the number average molecular weight in the range of 1000 to 2000, the stretchability and scratch resistance can be further improved. The number average molecular weight can be measured by techniques known in the art, such as gel permeation chromatography (GPC).

As the polymerizable compound A, a homopolymer having a glass transition temperature of 40 ° C. or higher is used.
The glass transition temperature of the homopolymer here is a single monomer or oligomer (polymerizable compound A) and 1-hydroxycyclohexyl phenyl ketone (1,2-α-hydroxyalkylphenone-based initiator) as an initiator. The mixture (monomer / initiator mass ratio: 97/3) was irradiated with ultraviolet rays having an energy of 10,000 mJ / cm ² to form a polymer, and this polymer was subjected to a differential calorimeter ( DSC-60A manufactured by Shimadzu Corporation) means a glass transition temperature. A suitable range is 40 ° C. or higher, preferably 50 ° C. or higher, and more preferably 60 ° C. or higher from the viewpoint of scratch resistance of the cured product.

Examples of the polymerizable compound A include those having a polymerizable ethylenically unsaturated double bond, specifically, an aromatic urethane acrylate oligomer, an aliphatic urethane acrylate oligomer, an epoxy acrylate oligomer, a polyester acrylate oligomer, Other special oligomers may be mentioned.
For example, the following are mentioned as goods.
CN902, CN940, CN963, CN963A80, CN963B80, CN963E75, CN963E80, CN963J85, CN970, CN970A60, CN970E60, CN983C, N985C900, N985C900, N985C900 CN9167, EBECRYL220, 264, 284, 285, 1259, 4858, 8701, 436, 438, 1830, 600, 605, 303, KRM8667, etc., manufactured by Daicel Ornex Co., are not limited thereto. Two or more kinds can be used in combination.

  The content of the polymerizable compound A is preferably 3 to 12% by mass with respect to the total mass (100% by mass) of the ink composition, and more preferably 5 to 8% by mass from the viewpoint of scratch resistance and dischargeability.

Furthermore, it is preferable that the polymerizable compound A is a compound having a branched structure having 2 or less functional groups, whereby the stretchability and scratch resistance can be further improved.
Specific examples of these compounds include, but are not limited to, CN963, CN963A80, CN963B80, CN963E75, CN963E80, CN963J85 manufactured by Sartomer.

Furthermore, when the polymerizable compound A is a compound having an alicyclic structure, the stretchability and the scratch resistance can be further improved. As the alicyclic structure, an isoboronyl skeleton, a tricyclodecane skeleton, and an adamantane skeleton are preferably applied, but are not limited thereto.
Specific examples of these compounds include UA-022P manufactured by Shin-Nakamura Chemical Co., Ltd., but are not limited thereto.

[Polymerizable compounds other than the above]
Further, it may contain a polymerizable compound other than the above-mentioned “monofunctional polymerizable compound” and “polymerizable compound A”, and various monomers and oligomers such as conventionally known bifunctional and trifunctional or more polyfunctional ones are further used. It is possible (hereinafter referred to as “other polymerizable compound”).
Examples of the monomer include unsaturated carboxylic acids such as (meth) acrylic acid, itaconic acid, crotonic acid, isocrotonic acid and maleic acid, salts or esters thereof, urethane, amide and anhydride thereof, acrylonitrile, styrene, various types Unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.

  Examples of the oligomer include oligomers formed from the above monomers such as linear acrylic oligomers, epoxy (meth) acrylate, oxetane (meth) acrylate, aliphatic urethane (meth) acrylate, and aromatic urethane (meth). Acrylate and polyester (meth) acrylate are mentioned.

Among other polymerizable compounds, an ester of (meth) acrylic acid, that is, (meth) acrylate is preferable.
Among the (meth) acrylates, examples of the bifunctional (meth) acrylate include triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and dipropylene glycol di ( (Meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonane Di (meth) acrylate, neopentyl glycol di (meth) acrylate, dimethylol-tricyclodecane di (meth) acrylate, EO (ethylene oxide) adduct di (meth) acrylate of bisphenol A DOO, PO bisphenol A (propylene oxide) adduct di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, and polytetramethylene glycol di (meth) acrylate.

  Among the above (meth) acrylates, trifunctional or more polyfunctional (meth) acrylates include, for example, trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate. , Pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, glycerin propoxytri (meth) acrylate, cowprolactone modified trimethylolpropane tri (meth) acrylate, pentaerythritol Examples include ethoxytetra (meth) acrylate and caprolactam-modified dipentaerythritol hexa (meth) acrylate.

The calculation Tg according to the FOX equation is given below.
<FOX type>
1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ +... + W _i / Tg _i +... + W _n / Tg _n
[In the FOX formula, the glass transition temperature of the homopolymer of each monomer constituting the polymer composed of n types of monomers is Tg _i (K), and the mass fraction of each monomer is W _i ( W ₁ + W ₂ +... + W _i +... W _n = 1). ]
In the present invention, the bifunctional polymerizable compound is also added to the calculation of the above formula using the homopolymer Tg.

(Polymerization initiator)
The ink composition of this embodiment contains a photopolymerization initiator.
Any polymerization initiator may be used as long as it can generate active species such as radicals and cations by the energy of active energy rays and can initiate polymerization of the polymerizable compound. Cationic polymerization initiators can be used, and among them, radical polymerization initiators are preferably used. Moreover, you may use the polymerization accelerator which uses together with a polymerization initiator and accelerates | stimulates a polymerization reaction.

  Examples of the radical polymerization initiator include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazoles, and the like. Examples include compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds.

  Among these, since the curability of the ink can be particularly improved, it is preferable to use an acylphosphine oxide compound and a thioxanthone compound, and it is more preferable to use both in combination.

  Specific examples of the radical polymerization initiator include acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, Carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthio Xanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenyl Phosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2,4-diethylthioxanthone, and bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide Can be mentioned.

  Examples of commercially available radical polymerization initiators include IRGACURE 651 (2,2-dimethoxy-1,2-diphenylethane-1-one), IRGACURE 184 (1-hydroxy-cyclohexyl-phenyl-ketone), DAROCUR 1173 ( 2-hydroxy-2-methyl-1-phenyl-propan-1-one), IRGACURE 2959 (1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1 -One), IRGACURE 127 (2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl] -2-methyl-propan-1-one}, IRGACURE 907 ( 2-Methyl-1- (4-methylthiophenyl) -2-morpho Nopropan-1-one), IRGACURE 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1), IRGACURE 379 (2- (dimethylamino) -2-[(4- Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone), IRGACURE TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), IRGACURE 819 (bis (2, 4,6-trimethylbenzoyl) -phenylphosphine oxide), IRGACURE 784 (bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-) Yl) -phenyl) titanium), IRGACURE OXE 0 (1.2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)]), IRGACURE OXE 02 (ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime)), IRGACURE 754 (oxyphenylacetic acid, 2- [2-oxo-2-phenylacetoxyethoxy] ethyl ester and oxyphenylacetic acid, 2- (Mixture of (2-hydroxyethoxy) ethyl ester) (above, manufactured by BASF), Speedcure TPO (manufactured by Lambson), KAYACURE DETX-S (2,4-diethylthioxanthone) (Nippon Kayaku Co., Ltd.) , Ltd., Ltd. )), IRGACURE TPO (manufactured by BASF), and Ubekrill P36 (manufactured by UCB).

The said polymerization initiator may be used individually by 1 type, and may be used in combination of 2 or more type.
In order to obtain a sufficient curing rate, the polymerization initiator is preferably contained in an amount of 5 to 20% by mass with respect to the total mass (100% by mass) of the ink composition.

An amine compound can be used in combination as a polymerization accelerator.
Examples thereof include ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, butoxyethyl p-dimethylaminobenzoate, and the like. Is mentioned.

<Colorant>
As the colorant, various dyes and pigments can be used in consideration of the physical characteristics of the composition. As the pigment, an inorganic pigment or an organic pigment can be used. For example, a black pigment, a yellow pigment, a magenta pigment, a cyan pigment, a white pigment, a glossy pigment such as gold or silver can be used.

(Pigment)
In this embodiment, the light resistance of the ink composition can be improved by using a pigment as the coloring material.
As the pigment, both inorganic pigments and organic pigments can be used.

As the inorganic pigment, carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black and channel black, iron oxide, and titanium oxide can be used.
Examples of commercially available titanium oxide include CR60-2 (trade name, manufactured by Ishihara Sangyo Kashisha, Ltd.).

  Organic pigments include insoluble azo pigments, condensed azo pigments, azo lakes and chelate azo pigments, phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc. Polycyclic pigments, dye chelates (eg basic dye chelates, acid dye chelates, etc.), dye rakes (basic dye rakes, acid dye rakes), nitro pigments, nitroso pigments, aniline black, daylight A fluorescent pigment is mentioned.

  More specifically, as carbon black used as black ink, No. 2300, no. 900, MCF88, No. 33, no. 40, no. 45, no. 52, MA7, MA8, MA100, no. 2200B and the like (manufactured by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, Raven 700, and the like (above, Columbia Carbon, Carbon Reb 400, Carbon Co. Regal 330R, Regal 660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, etc. (Cabot Corp. CAB. , Color Black W2, Color Black FW2V, Color Black FW18, Color Black FW200, Color B1back S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex U, Printex U, Printex U, Printex U, Printex U, Printex U, Printex U, Printex U. Special Black 4 (manufactured by Degussa).

  Examples of pigments used in white ink include C.I. I. Pigment white 6, 18, and 21.

  Examples of pigments used in yellow ink include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 155, 167, 172, 180.

  Examples of pigments used in magenta ink include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48 (Ca), 48 (Mn), 57 (Ca), 57: 1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245, or C.I. I. Pigment violet 19, 23, 32, 33, 36, 38, 43, 50.

  Examples of pigments used for cyan ink include C.I. I. Pigment Blue 1, 2, 3, 15, 15: 1, 15: 2, 15: 3, 15:34, 15: 4, 16, 18, 22, 25, 60, 65, 66, C.I. I. Bat Blue 4, 60.

  Examples of pigments other than magenta, cyan, and yellow include C.I. I. Pigment green 7,10, C.I. I. Pigment brown 3, 5, 25, 26, C.I. I. Pigment orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, 63.

The said pigment may be used individually by 1 type, and may use 2 or more types together.
When the above pigment is used, the average particle size is preferably 300 nm or less, and more preferably 50 to 250 nm.
When the average particle diameter is in the above range, the ink composition is more excellent in reliability such as ejection stability and dispersion stability, and an image with excellent image quality can be formed.
Here, the average particle diameter in the present specification is measured by a dynamic light scattering method.

(dye)
In the present embodiment, a dye can be used as the color material.
The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used.
Examples of the dye include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C.I. I. Acid Red 52, 80, 82, 249, 254, 289, C.I. I. Acid Blue 9, 45, 249, C.I. I. Acid Black 1, 2, 24, 94, C.I. I. Food Black 1, 2, C.I. I. Direct Yellow 1,12,24,33,50,55,58,86,132,142,144,173, C.I. I. Direct Red 1,4,9,80,81,225,227, C.I. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, C.I. I. Directed Black 19, 38, 51, 71, 154, 168, 171, 195, C.I. I. Reactive Red 14, 32, 55, 79, 249, C.I. I. Reactive black 3, 4, and 35 are mentioned.

The said dye may be used individually by 1 type, and may use 2 or more types together.
The content of the color material is preferably 1 to 10% by mass with respect to the total mass (100% by mass) of the ink composition.

[Dispersant]
When the ink composition of this embodiment contains a pigment, it may further contain a dispersant in order to improve pigment dispersibility.
Although it does not specifically limit as a dispersing agent, For example, the dispersing agent currently used in preparing pigment dispersions, such as a polymer dispersing agent, is mentioned.
Specific examples include polyoxyalkylene polyalkylene polyamines, vinyl polymers and copolymers, acrylic polymers and copolymers, polyesters, polyamides, polyimides, polyurethanes, amino polymers, silicon-containing polymers, sulfur-containing polymers, fluorine-containing polymers, and epoxies. The thing which has 1 or more types of resin as a main component is mentioned.
Commercially available polymer dispersants include Ajinomoto Fine Techno's Ajisper series, LUBRIZOL's Solspers series (Solsperse 36000, etc.), BYK's Dispersic series, and Enomoto Kasei's Disparon series. It is done.

<Solvent>
The active energy ray-curable composition of the present invention may contain a solvent. Examples of the solvent include ether, ketone, xylene, ethyl acetate, cyclohexanone, toluene and the like, and should be distinguished from the reactive monomer used for dilution. Further, “not including a solvent” means substantially not including a solvent, and means 0.1% by mass or less.

[Other additives]
The ink composition of the present embodiment may contain other additives (components) other than the additives listed above.
Examples of other components include known polymerization inhibitors, surfactants, photosensitizers, and pigment dispersants.
Examples of other additives include conventionally known fixing agents, antifungal agents, preservatives, antioxidants, ultraviolet absorbers, chelating agents, and thickeners.

[Usage]
The active energy ray-curable composition of the present invention is not particularly limited as long as the active energy ray-curable material is generally used in the field, and can be appropriately selected according to the purpose. For example, a molding resin, It can be applied to paints, adhesives, insulating materials, release agents, coating materials, sealing materials, various resists, and various optical materials. Furthermore, the active energy ray-curable composition of the present invention is not only used as an ink to form two-dimensional characters and images, but also as a three-dimensional modeling material for forming a three-dimensional three-dimensional image (three-dimensional model). Can also be used.
For example, as a binder between powder particles used in the powder lamination method, which is one of three-dimensional modeling methods, and as shown in FIG. As shown in FIG. 4, the material jet method (stereolithography method) in which three-dimensional modeling is performed by sequentially laminating the materials that have been irradiated and cured, and the storage pool (accommodating portion) of the active energy ray-curable composition 5 as shown in FIG. 1 is irradiated with an active energy ray 4 to form a hardened layer 6 having a predetermined shape on the movable stage 3 and can be used as a three-dimensional object constituent material in an optical modeling method or the like in which three-dimensional modeling is performed by sequentially stacking these layers. . A three-dimensional modeling apparatus for modeling a three-dimensional modeled object using such an active energy ray-curable composition can use a known one, and is not particularly limited. A thing provided with a supply means, a discharge means, an active energy ray irradiation means, etc. can be used. The present invention also includes a cured product obtained by curing the active energy ray-curable composition and a molded product obtained by processing a structure in which the cured product is formed on a substrate such as a recording medium. . The molded product is obtained by subjecting a cured product or structure formed in a sheet shape or a film shape to a molding process such as heat stretching or punching, for example, an automobile, an OA device, an electric -It is suitably used for applications that require the surface to be molded after decorating, such as meters for electronic devices and cameras, and panels for operation units.

[About recording media]
Examples of the recording medium on which an image is formed by the ink of the present invention include paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics and the like, but are not particularly limited. The ink of the present invention is remarkably improved in image quality when printed on a non-ink-absorbing recording medium.
Examples of the non-ink-absorbing recording medium include plastic, glass, metal, and ceramics, but it is easy to obtain an effect when printing on a plastic that easily repels ink. Examples of the plastic include polyvinyl chloride, polyethylene, ionomer resin, polyvinylidene chloride, polypropylene, polyvinyl alcohol, polycarbonate, polyester, polyacrylonitrile, acrylic resin, ABS, polyacetal, polystyrene, cellophane, and a copolymer resin with ethylene. However, it is not particularly limited. Although it is possible to print on these three-dimensional molded products, it is more accurate to position the recording medium and the head when printing on a film by the melt extrusion method, solution casting method, calendar method, etc. Therefore, beautiful image quality can be obtained with respect to the printing speed. Further, the surface energy of these plastics is greatly different, and the dot diameter after ink landing may change by repelling ink. However, since the ink of the present invention provides good wettability to the recording medium, a good image quality can be obtained without causing a great change on these plastics.

[Image Forming Method and Forming Apparatus]
The image forming method of the present invention includes an irradiation step of irradiating active energy rays in order to cure at least the active energy ray-curable composition, and the image forming apparatus of the present invention irradiates active energy rays. An irradiating means for carrying out, and an accommodating part for accommodating the active energy ray-curable composition, and the container may be accommodated in the accommodating part. Furthermore, you may have the discharge process and discharge means which discharge an active energy ray hardening-type composition. A method for discharging is not particularly limited, and examples thereof include a continuous injection type and an on-demand type. Examples of the on-demand type include a piezo method, a thermal method, and an electrostatic method.

  FIG. 2 is an example of an image forming apparatus provided with an ink jet ejection unit. Ink is ejected to the recording medium 22 supplied from the supply roll 21 by each color printing unit 23a, 23b, 23c, 23d including ink cartridges and discharge heads of active energy ray curable inks of yellow, magenta, cyan, and black. Is done. Thereafter, the light is cured by irradiating active energy rays from the light sources 24a, 24b, 24c, and 24d for curing the ink, thereby forming a color image. Thereafter, the recording medium 22 is conveyed to the processing unit 25 and the printed matter winding roll 26. Each of the printing units 23a, 23b, 23c, and 23d may be provided with a heating mechanism so that the ink is liquefied by the ink discharge unit. If necessary, a mechanism for cooling the recording medium to about room temperature by contact or non-contact may be provided.

The recording medium 22 is not particularly limited, and examples thereof include paper, a film, a metal, a composite material thereof, and the like, and may be a sheet shape. Moreover, even if it is the structure which enables only single-sided printing, the structure which also enables double-sided printing may be sufficient.
Further, the active energy ray irradiation from the light sources 24a, 24b, and 24c may be weakened or omitted, and the active energy ray may be irradiated from the light source 24d after printing a plurality of colors. Thereby, energy saving and cost reduction can be achieved.

  The recorded matter recorded by the ink of the present invention is not only printed on a smooth surface such as ordinary paper or resin film, but also printed on a surface to be printed having irregularities, such as metal or ceramic. It includes those printed on a printing surface made of various materials. Further, by stacking two-dimensional images, it is possible to form an image having a stereoscopic effect (an image composed of two and three dimensions) or a three-dimensional object.

  FIG. 3 is a schematic view showing an example of another image forming apparatus (three-dimensional stereoscopic image forming apparatus) used in the present invention. The image forming apparatus 39 in FIG. 3 uses a head unit (movable in the AB direction) in which inkjet heads are arranged to discharge the first active energy ray-curable composition from the molded article discharge head unit 30 to the support. A second active energy ray-curable composition having a composition different from that of the first active energy ray-curable composition is discharged from the head units 31 and 32, and these respective compositions are cured by the adjacent ultraviolet irradiation means 33 and 34. While laminating. More specifically, for example, the second active energy ray-curable composition is ejected from the support ejection head units 31 and 32 on the model support substrate 37 and solidified by irradiation with active energy rays. After forming the first support layer having the reservoir, the first active energy ray-curable composition is discharged from the ejection head unit 30 for a molded article into the reservoir and is solidified by irradiation with active energy rays. Then, the step of forming the first modeled object layer is repeated a plurality of times while lowering the stage 38 movable in the vertical direction in accordance with the number of stacking, thereby stacking the support layer and the modeled object layer to form the three-dimensional modeled object 35. Is produced. Thereafter, the support laminate 36 is removed as necessary. In FIG. 3, only one shaped article discharge head unit 30 is provided, but two or more shaped article discharge head units 30 may be provided.

  The ink of the present invention has a serial method in which ink is ejected onto a recording medium by moving the head relative to a recording medium that moves intermittently according to the head width, and the recording medium is moved continuously at a fixed position. The ink jet recording apparatus can be used for any line type ink jet recording apparatus in which ink is ejected from a head held on a recording medium onto a recording medium.

(Inkjet head)
Inkjet heads include recording heads that use piezoelectric elements, recording heads that use heating elements, and recording heads that use electrostatic attraction, but those that use piezoelectric elements are more flexible in terms of ejection force and ink configuration. In terms of surface. The nozzle surface of such an ink jet head is desirably surface-treated so as to have ink repellency. The surface treatment method may be vapor deposition, application, or plating of an ink repellent material, and can be selected according to the characteristics of the ink repellent material and the constituent material of the nozzle surface. Examples of the ink repellent material include fluorine-based compounds and silicone resins. Among them, PTFE that can be processed by eutectoid plating and silane compounds having vapor-deposited perfluoroalkyl are preferable in terms of the strength and ink repellency of the ink repellent layer. .

<Composition container>
The composition storage container of the present invention means a container in which the active energy ray-curable composition is stored, and is preferably used for the above applications.
For example, when the active energy ray-curable composition of the present invention is used for ink, the container in which the ink is stored can be used as an ink cartridge. This eliminates the need for direct contact and prevents dirt on fingers and clothes. In addition, foreign matters such as dust can be prevented from entering the ink. Further, the shape, size, material, and the like of the container itself may be suitable for use and usage, and are not particularly limited, but the material is preferably light-shielding.

  FIG. 1 shows an example of an ink cartridge. The ink bag 11 has an ink inlet 12 and an ink outlet 13. After the ink bag 11 is filled with ink from the ink inlet 12 and the air remaining in the ink bag 11 is exhausted, the ink inlet 12 is fused and sealed. When the ink bag 11 is used, the ink discharge port 13 is pierced with a needle formed in the main body of an ink discharge apparatus such as an ink jet recording apparatus, and ink is supplied to the apparatus. The ink discharge port 13 is formed from a rubber member or the like. The ink bag 11 is accommodated in a plastic cartridge case 14 and is detachably attached to the ink jet recording apparatus as the ink cartridge 10. By adopting a detachable configuration, the efficiency of operations such as ink replenishment and replacement can be improved.

[Discharge process]
In the ejection step, a conventionally known ink jet recording apparatus can be used. The ejection of the ink composition is preferably performed at a predetermined value of the viscosity of the ink composition.
The ink composition can be discharged after the viscosity is lowered to a predetermined value by heating the ink composition to a predetermined temperature. The predetermined value is preferably 25 mPa · s or less, more preferably 5 to 20 mPa · s. In this way, good discharge stability is realized.

  Since the ultraviolet curable ink composition of the present embodiment has a higher viscosity than the water-based ink composition used in ordinary ink jet recording ink, the viscosity fluctuation due to temperature fluctuation during ejection is large. Such fluctuations in the viscosity of the ink have a great influence on the change in the droplet size and the change in the droplet discharge speed, which can cause image quality deterioration. Therefore, it is preferable to keep the temperature of the ink during ejection as constant as possible.

[Curing process]
Next, in the curing step, the ink composition ejected on the recording medium is cured by irradiation with ultraviolet rays (light). This is because the photopolymerization initiator contained in the ink composition is decomposed by irradiation with ultraviolet rays to generate starting species such as radicals, acids, and bases, and the polymerization reaction of the polymerizable compound depends on the function of the starting species. It is to be promoted. Or it is because the polymerization reaction of a polymeric compound starts by irradiation of an ultraviolet-ray. At this time, if a sensitizing dye is present together with the photopolymerization initiator in the ink composition, the sensitizing dye in the system absorbs ultraviolet rays to be in an excited state and contacts the photopolymerization initiator to decompose the photopolymerization initiator. And a more sensitive curing reaction can be achieved.

  As an ultraviolet ray source, a mercury lamp, a gas / solid laser or the like is mainly used. As a light source used for curing a photocurable ink composition, a mercury lamp and a metal halide lamp are widely known. On the other hand, there is a strong demand for mercury-free from the viewpoint of environmental protection, and replacement with a GaN-based semiconductor ultraviolet light-emitting device is very useful industrially and environmentally. Furthermore, an ultraviolet light emitting diode (UV-LED) and an ultraviolet laser diode (UV-LD) are small, have a long lifetime, high efficiency, and low cost, and are preferable as a light source for ultraviolet curable ink jet. Among these, UV-LED is particularly preferable.

Here, it is preferable that the emission peak wavelength is an ultraviolet ray preferably in the range of 350 to 420 nm, more preferably in the range of 365 to 405 nm. If the ink composition of the present embodiment can be cured at the emission peak wavelength within the above range, it can be cured at low energy and at a high speed due to the composition of the ink composition in the present embodiment.
At the time of the irradiation energy is preferably 1000 mJ / cm ² or less, 150~500mJ / cm ² is more preferable.
The irradiation energy is calculated by multiplying the irradiation time by the irradiation intensity.
There may be one or a plurality of emission peak wavelengths within the above wavelength range.
Even in the case where there are a plurality, the total irradiation energy of the ultraviolet rays having the emission peak wavelength is set as the irradiation energy.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated further more concretely, this invention is not limited by these Examples.

The base materials and materials used in the following examples and comparative examples are as follows.
<Base material>
Polycarbonate film (PC)
(Mitsubishi Engineering Plastics, Iupilon 100FE2000
Masking, thickness 100 μm),

<Material>
(Monofunctional polymerizable compound)
3,3,5-trimethylcyclohexanol acrylate: SR420 (manufactured by Sartomer)
Phenoxyethyl acrylate: PEA (Osaka Organic Industry Co., Ltd.)
Isobornyl acrylate: IBXA (Osaka Organic Industry Co., Ltd.)
Cyclic trimethylolpropane formal monoacrylate: SR531 (manufactured by Sartomer)

(Polymerizable compound A)
EBECRYL 8538, 4858, 767, 265, 264, 600, 438, 284 (manufactured by Daicel Ornex)
Branched structure-containing polymerizable compound A: CN963 (manufactured by Sartomer) Branched structure-containing alicyclic structure-containing polymerizable compound A: UA-022P (manufactured by Shin-Nakamura Chemical Co., Ltd.)
(Other polymerizable compounds)
Polyethylene glycol (400) diacrylate: SR344 (manufactured by Sartomer)

(Photopolymerization initiator)
TPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (Irgacure TPO (manufactured by BASF))
DETX: 2,4-diethylthioxanthone (KAYACURE-DETX-S (manufactured by Nippon Kayaku Co., Ltd.))

(Pigment)
Carbon Black The compounding quantity was shown as a state containing the polymer dispersant S32000 manufactured by Nippon Lubrizol Co., Ltd. at a mass ratio of 3: 1 with respect to carbon black # 10 manufactured by Mitsubishi Chemical Corporation.

(Surfactant)
BYK 3510: Polyether-modified polysiloxane (by Big Chemie)
(Polymerization inhibitor)
MEHQ (hydroquinone monomethyl ether)

In the examples of the present invention, the Tg described as the physical property of the polymerizable compound refers to the glass transition point of the cured product of the homopolymer, where Tg takes the catalog value when there is a catalog value and there is no catalog value. In the case, it was measured by a differential scanning calorimetry (DSC) method. A mixture of simple substance (A) and 1-hydroxycyclohexyl phenyl ketone (1,2-α-hydroxyalkylphenone initiator) as an initiator (mass ratio of simple substance (A) / initiator: 97/3) Is irradiated with ultraviolet rays having an energy of 10,000 mJ / cm ² to form a polymer, and this polymer is measured with a differential heat measuring device (manufactured by Mac Science Co., Ltd., TG-DTA (2000S)). It means the glass transition temperature when The measurement temperature was 30 ° C. to 300 ° C., and the heating rate was 2.5 ° C. per minute.

[Example 1]
The raw materials in Table 1 were added in order from those listed on the table with stirring. After stirring for 1 hour, it was confirmed that there was no undissolved residue, and filtration was performed with a membrane filter to remove coarse particles causing the clogging of the head, thereby preparing an ink. This ink was discharged onto a polycarbonate plate so as to have a film thickness of 10 μm by an ink jet discharging apparatus equipped with a GEN4 head (manufactured by Ricoh Printing Systems). Immediately after the discharge, UV light was irradiated at a light amount of 1000 mJ / cm ² with a UV-LED Firefly irradiator manufactured by Foseon, to obtain a cured product.
In Table 1, the numerical values of the polymerizable compound, the color material, and the photopolymerization initiator indicate “parts by mass”.

[Examples 2 to 11, Comparative Examples 1 to 9]
In the same manner as in Example 1, ink was prepared according to the formulation shown in Table 1, printed and cured to obtain a cured product.
About each obtained hardened | cured material, the abrasion resistance and stretchability were measured as follows. The results are shown in Table 1.

[Evaluation method]
(Abrasion resistance)
Using a scratch-resistant Gakushoku-type friction fastness tester AB-301 (manufactured by Tester Sangyo Co., Ltd.), a friction element with a white cotton cloth for friction (gold width 3) attached under conditions of a load of 500 g and a friction frequency of 50 The coating film region was rubbed together, and the surface state of the coating film region was visually observed.
The evaluation criteria are as follows.
(Evaluation criteria)
AA: There is no color transfer in the gold width, and no scratches are observed in the coating film area.
A: There is no color transfer in the gold width, and gloss scratches are observed in the coating film region.
B: There is a color transfer in the gold width, and scratches are observed in the coating film area.
C: There is color transfer in the gold width, and peeling is recognized in the coating film region.

評価基準は以下の通りである。
（評価基準）
ＡＡ： ２００％以上
Ａ： １５０％以上２００％未満
Ｂ： １００％以上１５０％未満
Ｃ： １００％未満 (Extensible)
For stretchability, a tensile test was performed under the following conditions, and stretchability (%) was calculated based on the following formula (1).
180 ° C elongation at break (pull test)
Tensile tester; Autograph AGS-5kNX (manufactured by Shimadzu Corporation),
Tensile speed: 20 mm / min,
Temperature; 180 ° C.
Sample: JIS K6251 Dumbbell shape (No. 6)

The evaluation criteria are as follows.
(Evaluation criteria)
AA: 200% or more A: 150% or more and less than 200% B: 100% or more and less than 150% C: Less than 100%

  According to the evaluation results of Examples 1 to 11, it can be seen that according to the present embodiment, a photocurable ink composition having excellent stretchability of a cured film and good scratch resistance can be provided.

1 Reservation pool (container)
DESCRIPTION OF SYMBOLS 3 Movable stage 4 Active energy ray 5 Active energy ray curable composition 6 Curing layer 10 Ink cartridge 11 Ink bag 12 Ink inlet 13 Ink outlet 21 Supply roll 22 Recording medium 23a, 23b, 23c, 23d Printing unit 24a, 24b, 24c, 24d Light source 25 Processing unit 26 Printed material take-up roll 30 Modeled product ejection head unit 31, 32 Supported body ejection head unit 33, 34 Ultraviolet irradiation means 35 Three-dimensional modeled product 36 Support layer stacking unit 37 Modeled product support substrate 38 Stage 39 Image forming apparatus

JP 2011-122063 A JP2013-142151A JP 2009-299057 A JP 2013-173907 A

Claims (12)

An active energy ray-curable composition comprising at least two or more monofunctional polymerizable compounds and a polyfunctional polymerizable compound,
The polyfunctional polymerizable compound includes a polymerizable compound A having a functional group number of 2 or 3, a number average molecular weight of 500 or more and 5000 or less, and a glass transition temperature of 40 ° C. or more when polymerized alone.
The content of the monofunctional polymerizable compound in the active energy ray-curable composition is 60% by mass or more and 75% by mass or less,
The content of the polymerizable compound A in the active energy ray-curable composition is 3% by mass or more and 12% by mass or less,
The polymerizable compound other than the polymerizable compound A is blended at a ratio such that the calculated value of the glass transition temperature of the polymer composed of the polymerizable compound other than the polymerizable compound A is 25 ° C. or higher in the formula of FOX. An active energy ray-curable composition characterized by comprising:   The ratio of the two or more monofunctional polymerizable compounds to each other is such that the glass transition temperature calculated in the FOX formula for the polymer composed only of the monofunctional polymerizable compound is 35 ° C. or higher. The active energy ray-curable composition according to claim 1.   The active energy ray-curable composition according to claim 1, wherein the polymerizable compound A has a glass transition temperature of 50 ° C. or higher when polymerized alone.   The ratio between the two or more monofunctional polymerizable compounds is such that the glass transition temperature calculated in the FOX formula for the polymer consisting only of the monofunctional polymerizable compound is 35 ° C. or higher, The active energy ray-curable composition according to claim 1, wherein when the polymerizable compound A is polymerized alone, the polymer has a glass transition temperature of 50 ° C. or higher.   The active energy ray-curable composition according to claim 1, wherein the polymerizable compound A is a compound having a branched structure.   The active energy ray-curable composition according to claim 1, wherein the polymerizable compound A is a compound having an alicyclic structure.   An ink comprising the active energy ray-curable composition according to claim 1.   The ink according to claim 7, which is for inkjet.   A composition storage container in which the active energy ray-curable composition according to claim 1 is stored.   A two-dimensional image or a three-dimensional image is formed, comprising: a housing part in which the active energy ray-curable composition according to any one of claims 1 to 6 is contained; and an irradiation unit for irradiating the active energy ray. Image forming apparatus.   The image formation method which forms the two-dimensional image or three-dimensional image which has the process of irradiating an active energy ray curable composition in any one of Claims 1-6 with an active energy ray.   Hardened | cured material formed by hardening | curing the active energy ray curable composition in any one of Claims 1-6.

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