JP7070626B2 - UV curable compositions, inclusions and inkjet methods - Google Patents

Description

The present invention relates to UV curable compositions and inclusions.

The inkjet recording method is a relatively simple device that can record high-definition images, and is rapidly developing in various fields. Among them, various studies have been made on ink compositions used in an inkjet recording method for curing ink by irradiating it with ultraviolet rays. For example, Patent Document 1 intends to provide an ultraviolet curable inkjet ink that is stable, can be ejected with high landing accuracy, has excellent storage stability, and has excellent curability, and is at least an acid rather than a pigment or an amine value. An ultraviolet curable inkjet ink containing a high-value dispersant, a polymerizable compound, and a photopolymerization initiator, wherein the total amount of cationic impurities, metal impurities, and strongly acidic substances is 500 ppm or less. The ink is listed.

Japanese Unexamined Patent Publication No. 2005-200560

However, if the amount of impurities in the ultraviolet curable composition is simply reduced as in Patent Document 1, the curability of the composition may be lowered. On the other hand, it is also required to suppress the precipitation of foreign substances in the composition, and for that purpose, it is conceivable to reduce the water content in the ultraviolet curable composition as much as possible. However, if an attempt is made to excessively reduce the amount of water, an excessive number of steps and time are required to remove water from the polymerizable compound, and as a result, efficiency in producing an ultraviolet curable composition is achieved. Will decrease.

The present invention has been made to solve at least a part of the above-mentioned problems, and is an ultraviolet curable composition having excellent curability, capable of suppressing precipitation of foreign substances, and having high production efficiency thereof, and a composition thereof. It is an object of the present invention to provide a container for filling an object.

The present inventors have diligently studied to solve the above problems. As a result, they have found that the above-mentioned problems can be solved by containing a predetermined amount of a specific kind of metal element together with a polymerizable compound and a predetermined amount of water in the ultraviolet curable composition, and completed the present invention. ..

That is, the present invention is as follows.
[1] An ultraviolet curable composition containing a polymerizable compound and contained in an accommodating body.
The water content is 0.05% by mass or more and 1.0% by mass or less with respect to the total amount of the ultraviolet curable composition, and Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, UV curing in which the content of one or more metal elements selected from the group consisting of Al and Zr is 10 mass ppm or more, and the content of the metal element contained in the group is 250 mass ppm or less, respectively. Mold composition.
[2] The ultraviolet curable composition according to [1], which is an inkjet composition.
[3] The ultraviolet curable composition according to [1] or [2], which contains the one or more metal elements in at least one form of a metal ion and a metal salt.
[4] The ultraviolet curable composition according to any one of [1] to [3], which is a radical polymerization type ultraviolet curable composition.
[5] The ultraviolet curable composition according to any one of [1] to [4], which contains an acylphosphine oxide-based photopolymerization initiator.
[6] The ultraviolet curable composition according to any one of [1] to [5], which contains a polymerizable compound having a vinyl ether group as the polymerizable compound.
[7] The ultraviolet curable composition according to [6], which contains the polymerizable compound having a vinyl ether group in an amount of 10 to 70% by mass based on the total amount of the ultraviolet curable composition.
[8] As the polymerizable compound having a vinyl ether group, the following general formula (1):
CH ₂ = CR ¹ -COOR ² -O-CH = CH-R ³ ... (1)
(In the formula, R ¹ is a hydrogen atom or a methyl group, R ² is a divalent organic residue having 2 to 20 carbon atoms, and R ³ is a hydrogen atom or a monovalent organic residue having 1 to 11 carbon atoms. The ultraviolet curable composition according to [6] or [7], which contains a polymerizable compound represented by ().
[9] Among the metal elements contained in the group, there are three or more kinds of metal elements having a content of 10 to 250 mass ppm with respect to the total amount of the ultraviolet curable composition [1] to [8]. ] The ultraviolet curable composition according to any one of.
[10] An accommodating body containing the ultraviolet curable composition according to any one of [1] to [9].
[11] A container comprising a container containing a fatty acid ester as a plasticizer and the ultraviolet curable composition according to any one of [1] to [9] filled in the container.

It is an exploded perspective view which shows an example of the containment body of this invention.

Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail with reference to the drawings as necessary, but the present invention is not limited thereto. Various modifications are possible within the range that does not deviate from the gist. In the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. In addition, the positional relationship such as up, down, left, and right shall be based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios in the drawings are not limited to the ratios shown. Further, in the present specification, "(meth) acrylic" means "acrylic" and its corresponding "methacrylic", and "(meth) acrylate" means "acrylate" and its corresponding "methacrylate".

[Ultraviolet curable composition]
The ultraviolet curable composition of the present embodiment is one selected from the group consisting of a polymerizable compound, water, Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, Al and Zr. It contains the above-mentioned metal elements and is contained in an accommodating body. The amount of water contained therein is 0.05% by mass or more and 1.0% by mass or less with respect to the total amount of the ultraviolet curable composition. Further, for the entire amount of the ultraviolet curable composition, one or more selected from the group consisting of Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, Al and Zr contained therein. The content of the metal element (hereinafter, also referred to as “specific metal element”) is 10% by mass or more, and the content of the metal element contained in the above group is 250% by mass or less, respectively. The ultraviolet curable composition is preferably a radical polymerization type ultraviolet curable composition from the viewpoint of further enhancing the curability, and from the viewpoint of seeking high versatility and high convenience.

The ultraviolet curable composition may have more sufficient curability by containing 10% by mass or more of a specific metal element together with the polymerizable compound. It is considered that this is because the specific metal element acts effectively as a catalyst for the curing reaction of the polymerizable compound by containing 10% by mass or more of the specific metal element. Further, in the composition, the content of the metal element contained in the above group is 250% by mass or less, and the water content in the ultraviolet curable composition is 1.0% by mass or less, so that the foreign matter is contained. It is possible to suppress precipitation. This is because foreign substances are considered to precipitate due to metal elements existing in the form of metal ions or metal salts in water. By reducing the content of water and metal elements to a predetermined amount or less, the metal in water It is presumed that the precipitation of foreign substances is suppressed by reducing the amount of metal elements present in the form of ions or metal salts. Further, by setting the water content in the ultraviolet curable composition to 0.05% by mass or more, the production efficiency of the ultraviolet curable composition can be improved. In particular, the water content in the UV curable composition is highly dependent on the water content present (mixed) in the synthesized polymerizable compound, and the water content in the UV curable composition is 0.05% by mass or more. Therefore, it is presumed that the load based on the step of reducing the amount of water present in the polymerizable compound can be reduced. As a result, it becomes possible to shorten the manufacturing time, simplify the process, reduce the labor, and reduce the manufacturing cost. However, the factors are not limited to these.

The UV curable composition can be used for various purposes, and the use is not limited. Applications include, for example, inks and polymerization moldings. Among these, from the viewpoint of more effectively and surely exerting the action and effect of the present invention, it is preferably for ink, and it is also preferable for inkjet. Hereinafter, the ultraviolet curable composition of the present embodiment is used as an inkjet ink composition (hereinafter, also simply referred to as “composition”) which is one embodiment of an inkjet composition (composition used by ejecting by an inkjet method). The case of use will be described in more detail, but the ultraviolet curable composition is not limited to this.

(Polymerizable compound)
The composition contains a polymerizable compound. The polymerizable compound can be polymerized alone or by the action of a polymerization initiator by applying energy such as light irradiation to cure the composition on the recording medium. The polymerizable compound is not particularly limited, but conventionally known monofunctional, bifunctional, and trifunctional or higher polyfunctional monomers and oligomers can be used. The polymerizable compound may be used alone or in combination of two or more. Hereinafter, these polymerizable compounds will be exemplified.

The polymerizable compound preferably contains a radically polymerizable compound from the viewpoint of further enhancing the curability of the composition and from the viewpoint of seeking high versatility and high convenience. In addition to or instead, the polymerizable compound is a vinyl ether group from the viewpoint of increasing the curability, further lowering the viscosity of the composition, and increasing the solubility of the polymerization initiator when the polymerization initiator is used. It is preferable to contain the polymerizable compound having. As the polymerizable compound having a vinyl ether group, a radically polymerizable compound having a vinyl ether group is preferable. Examples of such a polymerizable compound include (meth) acrylates having a monofunctional or polyfunctional vinyl ether group, and these are preferable from the same viewpoints as described above.

The monofunctional (meth) acrylate having a vinyl ether group is not particularly limited, but from the viewpoint of lowering the viscosity of the composition, having a high flash point, and further enhancing the curability of the composition, the following general formula (1) :
CH ₂ = CR ¹ -COOR ² -O-CH = CH-R ³ ... (1)
It is preferable to contain a polymerizable compound represented by. Here, in the formula (1), R ¹ is a hydrogen atom or a methyl group, R ² is a divalent organic residue having 2 to 20 carbon atoms, and R ³ is a hydrogen atom or 1 to 11 carbon atoms. It is a monovalent organic residue.

Examples of the polymerizable compound represented by the general formula (1) include 2-vinyloxyethyl (meth) acrylate, 3-vinyloxypropyl (meth) acrylate, and 1-methyl-2-vinyloxyethyl (meth) acrylate. , (Meta) 2-vinyloxypropyl acrylate, (meth) 4-vinyloxybutyl acrylate, (meth) 1-methyl-3-vinyloxypropyl acrylate, 1-vinyloxymethylpropyl (meth) acrylate, (meth) ) 2-Methyl-3-vinyloxypropyl acrylate, 1,1-dimethyl-2-vinyloxyethyl (meth) acrylate, 3-vinyloxybutyl (meth) acrylate, 1-methyl-2-vinyloxy (meth) acrylate Propyl, 2-vinyloxybutyl (meth) acrylate, 4-vinyloxycyclohexyl (meth) acrylate, 6-vinyloxyhexyl (meth) acrylate, 4-vinyloxymethylcyclohexylmethyl (meth) acrylate, (meth) acrylic Acid 3-vinyloxymethylcyclohexylmethyl, (meth) acrylic acid 2-vinyloxymethylcyclohexylmethyl, (meth) acrylic acid p-vinyloxymethylphenylmethyl, (meth) acrylic acid m-vinyloxymethylphenylmethyl, (meth) ) Acrylic acid o-vinyloxymethylphenylmethyl, (meth) acrylic acid 2- (vinyloxyethoxy) ethyl, (meth) acrylic acid 2- (vinyloxyisopropoxy) ethyl, (meth) acrylic acid 2- (vinyloxy) Ethoxy) propyl, 2- (vinyloxyethoxy) isopropyl (meth) acrylate, 2- (vinyloxyisopropoxy) propyl (meth) acrylate, 2- (vinyloxyisopropoxy) isopropyl (meth) acrylate, (meth) ) Acrylic acid 2- (vinyloxyethoxyethoxy) ethyl, (meth) acrylic acid 2- (vinyloxyethoxyisopropoxy) ethyl, (meth) acrylic acid 2- (vinyloxyisopropoxyethoxy) ethyl, (meth) acrylic acid 2- (Vinyloxyisopropoxyisopropoxy) ethyl, (meth) acrylate 2- (vinyloxyethoxyethoxy) propyl, (meth) acrylate 2- (vinyloxyethoxyisopropoxy) propyl, (meth) acrylate 2- (Vinyloxyisopropoxyethoxy) propyl, (meth) acrylate 2- (vinyloxyisopropoxyisopropoxy) propyl, (meth) acrylate 2- (vinyloxyethoxyethoxy) isopropyl, 2- (Meta) Acrylic Acid 2- (Vinyloxyisopropoxy) isopropyl, (Meta) Acrylic Acid 2- (Vinyloxyisopropoxyethoxy) isopropyl, (Meta) Acrylic Acid 2- (Vinyloxyisopropoxyisopropoxy) isopropyl, ( Examples thereof include 2- (vinyloxyethoxyethoxyethoxy) ethyl (meth) acrylic acid and 2- (vinyloxyethoxyethoxyethoxyethoxy) ethyl (meth) acrylic acid. These may be used alone or in combination of two or more.

Among these, from the same viewpoint as above, 2- (vinyloxyethoxy) ethyl (meth) acrylate, that is, 2- (vinyloxyethoxy) ethyl acrylate and 2- (vinyloxyethoxy) ethyl methacrylate Of these, at least one is preferable, and 2- (vinyloxyethoxy) ethyl acrylate is more preferable. Both 2- (vinyloxyethoxy) ethyl acrylate and 2- (vinyloxyethoxy) ethyl methacrylate have a simple structure and a small molecular weight, so that the composition can be significantly reduced in viscosity. Examples of 2- (vinyloxyethoxy) ethyl (meth) acrylate include 2- (2-vinyloxyethoxy) ethyl (meth) acrylate and 2- (1-vinyloxyethoxy) ethyl (meth) acrylate. Examples of 2- (vinyloxyethoxy) ethyl acrylate include 2- (2-vinyloxyethoxy) ethyl acrylate and 2- (1-vinyloxyethoxy) ethyl acrylate. In addition, 2- (vinyloxyethoxy) ethyl acrylate is superior to 2- (vinyloxyethoxy) ethyl methacrylate in terms of curability.

The content of the polymerizable compound having a vinyl ether group is preferably 10 to 70% by mass, more preferably 10 to 60% by mass, still more preferably 10 to 50% by mass, based on the total amount (100% by mass) of the composition. .. When the content is 10% by mass or more, the viscosity of the composition can be reduced, and the curability of the composition tends to be more excellent. On the other hand, when the content is 70% by mass or less, the composition tends to be more excellent in storage stability and the surface gloss of the printed matter tends to be more excellent.

The composition may contain one or more monofunctional, bifunctional, and trifunctional or higher polyfunctional monomers other than those exemplified above. Such monomers are not particularly limited, but are, for example, unsaturated carboxylic acids such as (meth) acrylic acid, itaconic acid, crotonic acid, isocrotonic acid and maleic acid; salts of the unsaturated carboxylic acid; Esters, urethanes, amides and anhydrides; examples include acryliconitriles, styrenes, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.

The monofunctional, bifunctional, and trifunctional or higher functional oligomers are not particularly limited, but are, for example, oligomers formed from the above monomers such as linear acrylic oligomers, epoxy (meth) acrylates, and oxetane (meth). Examples thereof include acrylates, aliphatic urethane (meth) acrylates, aromatic urethane (meth) acrylates and polyester (meth) acrylates.

Further, an N-vinyl compound may be contained as another monofunctional monomer or a polyfunctional monomer. The N-vinyl compound is not particularly limited, and examples thereof include N-vinylformamide, N-vinylcarbazole, N-vinylacetamide, N-vinylpyrrolidone, N-vinylcaprolactam, and acryloylmorpholine, and derivatives thereof. Will be.

The composition may contain a monofunctional (meth) acrylate as a monofunctional monomer. In this case, the composition has a low viscosity, has excellent solubility of a photopolymerization initiator and other additives, and tends to have good ejection stability during inkjet recording. The monofunctional (meth) acrylate is not particularly limited, and is, for example, isoamyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, and isomyristyl (meth). ) Acrylate, Isostearyl (meth) acrylate, 2-ethylhexyl-diglycol (meth) acrylate, 2-hydroxybutyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate , Methoxypolyethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxy Propyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, lactone-modified flexible (meth) acrylate, t-butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl Oxyethyl (meth) acrylate, 2- (isopropenoxyethoxy) ethyl (meth) acrylate, 2- (isopropenoxyethoxyethoxy) ethyl (meth) acrylate, 2- (isopropenoxyethoxyethoxyethoxy) ethyl (meth) Examples thereof include acrylate, 2- (isopropenoxyethoxyethoxyethoxyethoxy) ethyl (meth) acrylate, polyethylene glycol monovinyl ether (meth) acrylate, and polypropylene glycol monovinyl ether (meth) acrylate. Among these, phenoxyethyl (meth) acrylate is preferable.

The content of the monofunctional monomer is preferably 10 to 60% by mass, more preferably 20 to 50% by mass, based on the total amount (100% by mass) of the composition. By setting the above preferable range, the curability, initiator solubility, storage stability, and ejection stability tend to be more excellent.

The composition may contain a polyfunctional (meth) acrylate as the polyfunctional monomer. Among them, the bifunctional (meth) acrylate is not particularly limited, and for example, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and dipropylene glycol di (meth) acrylate. ) Acrylate, Tripropylene glycol di (meth) acrylate, Polyethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, dimethylol-tricyclodecanedi (meth) acrylate, EO (ethylene oxide) adduct of bisphenol A di (meth) acrylate, PO (propylene oxide) of bisphenol A Additives Di (meth) acrylate, neopentyl glycol di (meth) acrylate hydroxypivalate, polytetramethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, and triethylene glycol di (meth) acrylate can be mentioned.

Examples of the trifunctional or higher functional (meth) acrylate include trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate. , Dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, glycerin propoxytri (meth) acrylate, cowprolactone-modified trimethylolpropane tri (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate, and Caprolactam-modified dipentaerythritol hexa (meth) acrylates can be mentioned.

Among these, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and pentaerythritol tri (meth) acrylate are preferable, and dipropylene. Glycoldi (meth) acrylate and pentaerythritol tri (meth) acrylate are more preferred.

The content of the polyfunctional monomer is preferably 5 to 60% by mass, more preferably 10 to 50% by mass, still more preferably 15 to 40% by mass, based on the total amount (100% by mass) of the composition. By setting the above preferable range, the curability, storage stability, ejection stability and surface gloss of the printed matter tend to be superior.

Further, in order to increase the toughness, heat resistance and chemical resistance of the cured film, it is preferable to use a monofunctional (meth) acrylate and a bifunctional (meth) acrylate in combination, among which phenoxyethyl (meth) acrylate and dipropylene glycol are used. It is more preferable to use di (meth) acrylate in combination.

The content of the polymerizable compound is preferably 35 to 95% by mass, more preferably 45 to 90% by mass, based on the total amount (100% by mass) of the composition. When the content of the polymerizable compound is within the above range, the viscosity and odor can be further lowered, and the solubility and reactivity of the photopolymerization initiator and the surface gloss of the printed matter are further improved. Can be done.

(Metallic element)
The composition of the present embodiment contains one or more metal elements selected from the group consisting of Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, Al and Zr. These specific metal elements are considered to act effectively as a catalyst for the polymerization reaction (curing reaction) of the polymerizable compound, particularly the radically polymerizable compound. The composition preferably contains a particular metal element in the form of at least one of a metal ion and a metal salt. When a specific metal element is present in the composition in the form of a metal ion or a metal salt, foreign matter is likely to precipitate, but according to the present invention, the precipitation of the foreign matter can be suppressed. It can be enjoyed more effectively.

The content of the specific metal element in the composition is 10% by mass or more, preferably 20% by mass or more, based on the total amount (100% by mass) of the composition, from the viewpoint of enhancing the curability of the composition. From the same viewpoint, the content of 3 or more kinds of metal elements selected from the above group is preferably 10 mass ppm or more, more preferably 20 mass ppm or more, and the content of 5 or more kinds of metal elements. Is more preferably 10% by mass or more, and further preferably 20% by mass or more. On the other hand, regarding the content of the metal elements contained in the above group, the content of each metal element is 250 mass ppm or less from the viewpoint of suppressing the precipitation of foreign substances. In other words, the content of any of the metal elements included in the above group is 250 mass ppm or less. From the same viewpoint, the content of each metal element is preferably 200 mass ppm or less, and more preferably 175 mass ppm or less. Further, from the viewpoint of further enhancing the curability of the composition, further suppressing the precipitation of foreign substances, and further improving the storage stability, the content of all the metal elements included in the above group is the total amount of the composition. It is preferable that the amount of the metal element, which is 10 to 250 mass ppm with respect to (100% by mass), is 3 or more, more preferably 5 or more, further preferably 8 or more, and 10 or more. It is particularly preferable, and 12 kinds, that is, all of them are extremely preferable. On the other hand, from the viewpoint of placing importance on further suppressing the precipitation of foreign substances, the content of the metal elements contained in the above group is 10 to 250 mass ppm with respect to the total amount (100 mass%) of the composition. The number of metal elements is preferably 10 or less, and more preferably 8 or less. Further, from the same viewpoint, among the metal elements contained in the above group, 3 or more and 10 or less metal elements having a content of 10 to 250 mass ppm with respect to the total amount (100 mass%) of the composition are used. It is preferable, and it is more preferable that it is 5 or more and 8 or less.

Examples of the method for adjusting the content of a specific metal element in each component of the composition include a method of purifying a pigment and adjusting the content of the metal element contained in the pigment, and a method of adjusting the content of the metal element in the pigment dispersion liquid. Examples include a method of adjusting the content of the composition and a method of selecting the material of the container with which the composition comes into contact. In addition, the content of a specific metal element in the composition is measured according to the method described in the following Examples.

(moisture)
The composition of the present embodiment contains water, and the water content is 0.05% by mass or more and 1.0% by mass or less with respect to the total amount (100% by mass) of the composition. This makes it possible to increase the production efficiency of the composition and further suppress the precipitation of foreign substances. Further, when the composition contains a polymerizable compound having a vinyl ether group, the storage stability of the composition can be enhanced, and when the composition contains an acylphosphine oxide-based photopolymerization initiator, the photopolymerization initiator can be used. It can be well dissolved in the composition. The water content is preferably 0.1% by mass or more from the viewpoint of further increasing the production efficiency of the composition. On the other hand, from the viewpoint of further suppressing the precipitation of foreign substances, from the viewpoint of further enhancing the storage stability of the composition when the composition contains a polymerizable compound having a vinyl ether group, and the viewpoint that the composition is an acylphosphine oxide-based photopolymerization initiator. When the photopolymerization initiator is contained, the photopolymerization initiator is more satisfactorily dissolved in the composition, and therefore, it is preferably 0.5% by mass or less.

As a method for adjusting the water content in the composition, for example, each component of the composition, for example, a polymerizable compound, a method for reducing the water content in the composition, a method for removing water from the composition, and a method for mixing in the composition at the time of preparation. Examples include a method of reducing the amount of water. Among these, as a method for reducing the amount of water in the polymerizable compound, more specifically, a method for distilling and purifying the polymerizable compound, a method for permeating the polymerizable compound through a semi-permeable film that selectively permeates water, and a method for permeating the polymerizable compound. And a method of selectively adsorbing water to a water adsorbent that adsorbs water can be mentioned. Among these, the method of distillation purification is preferable from the viewpoint of being able to reduce the water content more efficiently and surely. The water content is measured according to the method described in the examples below.

Examples of the water content include pure water such as ion-exchanged water, ultra-filtered water, reverse osmosis water, and distilled water, and ultrapure water from which ionic impurities have been removed as much as possible. Further, when water sterilized by irradiation with ultraviolet rays or addition of hydrogen peroxide or the like is used, it is possible to prevent the growth of mold and bacteria when the ink is stored for a long period of time. This tends to further improve storage stability.

In addition to the above-mentioned components, the composition of the present embodiment may contain any component that can be used in a conventional ultraviolet curable inkjet ink composition. Such optional components include, for example, polymerization initiators, colorants such as pigments and dyes, dispersants, polymerization inhibitors, surfactants, penetrants, moisturizers, solubilizers, viscosity modifiers, pH adjusters. Examples include agents, antioxidants, preservatives, fungicides, corrosion inhibitors, and chelating agents and other additives and solvents for capturing metal ions that affect dispersion. Each of these may be used alone or in combination of two or more.

(Polymer initiator)
The composition of the present embodiment may contain a polymerization initiator. The polymerization initiator is not limited as long as it generates active species such as radicals and cations by heat energy or light energy such as ultraviolet rays and initiates the polymerization of the above-mentioned polymerizable compound, but the photopolymerization initiator is not limited. Is preferable, and a photoradical polymerization initiator is preferable. The photoradical polymerization initiator is not particularly limited, but an acylphosphine oxide-based photopolymerization initiator and a thioxanthone-based photopolymerization initiator are preferable, and an acylphosphine oxide-based photopolymerization initiator is more preferable.

[Acylphosphine oxide-based photopolymerization initiator]
The composition preferably contains an acylphosphine oxide-based photopolymerization initiator. Acylphosphine oxide-based photopolymerization initiators are susceptible to oxygen inhibition, but are suitable for curing with long wavelength light LEDs. Further, the acylphosphine oxide-based photopolymerization initiator can be better dissolved in the composition when the water content in the composition is 1.0% by mass or less with respect to the total amount of the composition.

The acylphosphine oxide-based photopolymerization initiator is not particularly limited, but specifically, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. , And bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide.

The commercially available product of the acylphosphine oxide-based photopolymerization initiator is not particularly limited, and for example, IRGACURE 819 (trade name manufactured by BASF, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide), IRGACURE TPO ( BASF trade name, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), SPEEDCURE TPO (Lambson trade name, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide) and DAROCUR TPO (BASF) Product name, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide).

The content of the acylphosphine oxide-based photopolymerization initiator is preferably 1.0 to 10% by mass, more preferably 2.0 to 8.0% by mass, based on the total amount (100% by mass) of the composition. When the content is 1.0% by mass or more, the curability tends to be better. Further, when this content is 10% by mass or less, the dissolution and storage stability of the solid content are kept good, and the reliability tends to be better.

[Thioxanthone-based photopolymerization initiator]
The composition may contain a thioxanthone-based photopolymerization initiator. When the composition contains a thioxanthone-based photopolymerization initiator, the surface tackiness can be reduced, and in particular, the ink surface can be cured at the time of a thin film susceptible to oxygen inhibition to prevent color mixing and bleeding between dots. Further, it is preferable to use both an acylphosphine oxide-based photopolymerization initiator and a thioxanthone-based photopolymerization initiator because the curing process by UV-LED tends to be superior and the curability and adhesion of the composition tend to be further excellent.

The thioxanthone-based photopolymerization initiator is not particularly limited, but specifically, it preferably contains one or more selected from the group consisting of thioxanthone, diethylthioxanthone, isopropylthioxanthone, and chlorothioxanthone. Although not particularly limited, 2,4-diethylthioxanthone is preferable as diethylthioxanthone, 2-isopropylthioxanthone as isopropylthioxanthone, and 2chlorothioxanthone as chlorothioxanthone. A composition containing such a thioxanthone-based photopolymerization initiator tends to be more excellent in curability, storage stability, and ejection stability. Among these, a thioxanthone-based photopolymerization initiator containing diethylthioxanthone is preferable. By including diethylthioxanthone, there is a tendency that ultraviolet light (UV light) in a wide range can be converted into an active species more efficiently.

The commercial product of the thioxanthone-based photopolymerization initiator is not particularly limited, but specifically, Speedcure DETX (2,4-diethylthioxanthone), Speedcure ITX (2-isopropylthioxanthone) (hereinafter, manufactured by Rambson), KAYACURE. DETX (2,4-diethylthioxanthone) (manufactured by Nippon Kayaku Co., Ltd.) can be mentioned.

The content of the thioxanthone-based photopolymerization initiator is preferably 0.5 to 5.0% by mass, more preferably 1.0 to 4.0% by mass, based on the total amount (100% by mass) of the composition. When the content is 0.5% by mass or more, the surface tackiness can be further reduced, and the ink surface can be cured at the time of a thin film susceptible to oxygen inhibition to further prevent color mixing and bleeding between dots. It is in. Further, when the content is 5.0% by mass or less, the ink is less colored by the initiator itself, the hue is less yellowed, and the adhesion of the cured film tends to be superior.

(Other photopolymerization initiators)
The composition may further contain one or more of a photoradical polymerization initiator or a photocationic polymerization initiator other than the above. Examples of the photoradical polymerization initiator other than the above include aromatic ketones, aromatic onium salt compounds, organic peroxides, thio compounds (thiophenyl group-containing compounds, etc.), α-aminoalkylphenone compounds, and hexaarylbiimidazole. Examples thereof include compounds, ketooxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds.

Commercially available products of photoradical polymerization initiators other than the above are not particularly limited, but are, for example, IRGACURE 651 (2,2-dimethoxy-1,2-diphenylethan-1-one) and IRGACURE 184 (1-hydroxy-cyclohexyl). -Phenyl-ketone), DAROCUR 1173 (2-hydroxy-2-methyl-1-phenyl-propane-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-propane -1-on}, IRGACURE 907 (2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one), IRGACURE 369 (2-benzyl-2-dimethylamino-1- (4-) Morphorinophenyl) -butanone-1), IRGACURE 379 (2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone), IRGACURE 784 (bis (η5-2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium), IRGACURE OXE 01 (1. 2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)]), IRGACURE OXE 02 (ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H- Carbazole-3-yl]-, 1- (O-acetyloxime)), IRGACURE 754 (oxyphenylacetic acid, 2- [2-oxo-2-phenylacetoxyethoxy] ethyl ester and oxyphenylacetic acid, 2- (2- (2-) Mixture of hydroxyethoxy) ethyl ester) (above, manufactured by BASF), Speedcure TPO (above, manufactured by Rambson), Lucirin TPO, LR8883, LR8970 (above, manufactured by BASF), and Yubekryl P36 (manufactured by UCB). Be done.

The other photocationic polymerization initiator is not particularly limited, and specific examples thereof include a sulfonium salt and an iodonium salt.

The content of the photopolymerization initiator is preferably 5 to 20% by mass with respect to the total amount (100% by mass) of the composition. When the content is within the above range, the ultraviolet curing rate tends to be sufficiently exhibited, and the undissolved residue of the photopolymerization initiator and the coloring derived from the photopolymerization initiator tend to be avoided.

(Color material)
The coloring material is not particularly limited, and examples thereof include pigments and dyes.

Examples of the pigment include inorganic pigments and organic pigments. The inorganic pigment is not particularly limited, and examples thereof include carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, and channel black, iron oxide, and titanium oxide.

The organic pigment is not particularly limited, but for example, quinacridone pigment, quinacridone quinone pigment, dioxazine pigment, phthalocyanine pigment, anthrapyrimidine pigment, anthanthrone pigment, indanslon pigment, flavanthron pigment, Examples thereof include perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, isoindolinone pigments, azomethine pigments, and azo pigments. ..

Pigments may be used alone or in combination of two or more.

The content of the pigment is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and more preferably 1.0 to 5.0% by mass with respect to the total amount (100% by mass) of the composition. More preferred. When the content of the pigment is within the above range, the color-developing property tends to be better.

The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used. As the dye, for example, 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. Hood 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. Dilekdo 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, 35 can be mentioned.

Dyes may be used alone or in combination of two or more.

The content of the dye is preferably 1.0 to 20% by mass with respect to the total amount (100% by mass) of the composition from the viewpoint of obtaining excellent hiding power and color reproducibility.

(Dispersant)
When the composition contains a pigment, one or more dispersants may be further contained in order to improve the dispersibility of the pigment. The dispersant is not particularly limited, and examples thereof include dispersants commonly used for preparing a pigment dispersion such as a polymer dispersant. Specific examples thereof 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. Examples thereof include resins containing one or more of the main components. Commercially available polymer dispersants include Ajinomoto Fine-Techno's Azisper series, Lubrizol's Solspers series (eg, "Solsperse 36000"), BYK Chemie's Disperbic series, Kusumoto Kasei. The Disparon series manufactured by the company can be mentioned.

(Polymerization inhibitor)
The composition may contain one kind or two or more kinds of polymerization inhibitors from the viewpoint of further enhancing the storage stability thereof. The polymerization inhibitor is not particularly limited, and for example, a compound having a 2,2,6,6-tetramethylpiperidine-N-oxyl skeleton, a compound having a 2,2,6,6-tetramethylpiperidine skeleton, 2 , 2,6,6-Tetramethylpiperidin-N-alkyl skeletons, and hindered amine compounds such as 2,2,6,6-tetramethylpiperidine-N-acyl skeletons; p-methoxyphenol, hydroquinone Monomethyl ether (MEHQ), hydroquinone, cresol, t-butylcatechol, 3,5-di-t-butyl-4-hydroxytoluene, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2, Examples thereof include 2'-methylenebis (4-ethyl-6-butylphenol) and 4,4'-thiobis (3-methyl-6-t-butylphenol).

The ultraviolet curable composition of the present embodiment is to be housed in an container. In other words, the container of the present embodiment contains the ultraviolet curable composition of the present embodiment. Hereinafter, the case where the ultraviolet curable composition is used as the ink composition for inkjet will be described in more detail.

(Containment body)
Examples of the housing of the present embodiment include, but are not limited to, ink cartridges, packs, bottles, tanks, bottles, and cans. Among these, ink cartridges, packs, bottles, and tanks are preferable, and packs are more preferable, because they are widely used and the water vapor transmittance described later can be easily controlled to a desired value. Further, the container having a container (pack) using a flexible film as a container (in the container, a member filled with the composition and substantially holding the composition) filled with the composition of the container. However, it is lightweight, it is easy to put the container in a box-shaped container, the volume of the container easily changes according to the remaining amount of the composition, and the film is heat-sealed and processed into a bag shape. It is preferable in that it can be used as a product.

In addition, as a usage mode of the housing of the present embodiment, there are a form such as an ink cartridge which is separate from the recording device and is mounted on the recording device and sequentially supplies the composition to the recording device, and (B). ) It is a separate body from the recording device, and when the composition is used, only the composition is transferred from the accommodating body to the recording device, and (C) the form of a tank or the like provided in the recording device in advance and accommodating the composition is available. At least.

The above-mentioned (A) and (B) can be said to be the contents of the composition from the time when the contents are shipped until immediately before the composition is supplied (transferred) to the recording device. The above (C) can be said to be a container of the composition from the time when the recording device is shipped to the time when the recording device starts to use the composition for the first time. In addition, the above-mentioned (A) and (C) are the accommodation of the composition which prints a recording apparatus in a state where the composition is supplied to the recording apparatus from a container through a connection part such as an ink tube. Can be done. Further, the above-mentioned (B) can be said to be an container of a composition for which printing is performed by the recording device after the composition is transferred from the container to the recording device. The target to which the composition is transferred in the said (B) is a tank or the like provided in the recording device.

The constituent material of the container in which the composition is filled is not limited to the following, and for example, polyethylene terephthalate (PET), polypropylene (PP), polyethylene, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer (EVOH). , And polystyrene, and these films may be used. The above may be blended in an appropriate ratio, or a plurality of the above may be layered to form a composition. In the case of a film, it may be obtained by laminating. When a plurality of types of films are stacked, it is not necessary that all of the plurality of types of films are the above-mentioned films, and a part thereof may be a film composed of other materials, for example, a metal and a metal compound.

Further, from the viewpoint of increasing the flexibility of the container, it is preferable that a plasticizer is contained as a constituent material of the container. Examples of the plasticizer include fatty acid esters, epoxy compounds, and polyester compounds. Among these, fatty acid esters are preferable from the viewpoint of versatility as a plasticizer, and examples of such fatty acid esters include phthalates, adipates, trimellitic acids and citrates. Fatty acid esters may be used alone or in combination of two or more.

If the container contains a plasticizer as its constituent material, it is believed that the plasticizer elutes into the composition and forms a metal salt with certain metal elements in the composition. Then, it is presumed that the metal salt is one of the factors for precipitating foreign substances in the composition. Since the composition of the present invention has an effect of suppressing the precipitation of such foreign substances, the benefits based on the present invention can be more effectively enjoyed when the container contains a plasticizer as a constituent material thereof.

The containment may be agitated during storage and transport to release sedimentation of the components contained in the containing composition. This is because if a long period of time elapses after the sedimentation of the components contained in the composition, the sediment may become a cake and it may be difficult to release the sediment. Further, when supplying the composition from the container to the recording device, it is preferable to stir the container to release the sedimentation.

When the container is a container (pack) using a flexible film, durability that does not cause cracks or tears is required especially with the stirring operation. Examples of such a durable film material include plastic films such as polyethylene terephthalate (PET), polypropylene, polyethylene, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer, and polystyrene, and ethylene acetic acid is preferable. Vinyl copolymers are more preferred. Preferred examples of the film include stretched plastic films such as high-density, low-density, or linear low-density polyethylene, polypropylene, ethylene-vinyl alcohol copolymer, and polystyrene. It may be a laminated film in which a plurality of layers of films are laminated.

When the container is the above-mentioned pack, when the components contained in the composition settle, the pack may be shaken left and right to stir the ink and recover the settling. In that case, it is preferable to contain a plasticizer as a constituent material of the pack from the viewpoint of preventing the occurrence of cracks and tears in the pack. As the plasticizer, any of the above-mentioned ones may be used, and fatty acid esters are preferable.

When the container is the above-mentioned pack, the water vapor transmittance of the film constituting the pack is preferably 30 g / ^m 2.24 hrs or less, more preferably 15 g / ^m 2.24 hrs or less, and 10 g / m. It is more preferably ^m 2.24 hrs or less, and particularly preferably 5.0 g / ^m 2.24 hrs or less. By using a film having a water vapor transmittance of 30 g / ^m 2.24 hrs or less, it is possible to suppress an increase in the water content in the composition packed in the pack even if the pack is stored for a long period of time. In order to make the water vapor transmittance 30 g / ^m 2.24 hrs or less, for example, the material constituting the film may be selected, or the film may be provided with a layer composed of at least one of a metal and a metal compound. Among these, from the viewpoint of high versatility, it is preferable to provide a layer composed of at least one of a metal and a metal compound. Examples of the metal include Al and Ti. The metal compound is preferably a metal oxide, and examples thereof include alumina, silica, titania and zirconia. These may be used alone or in combination of two or more. In this specification, the metal oxide includes silica.
The thickness of the film constituting the pack is preferably 50 to 200 μm, more preferably 70 μm or more, further preferably 80 μm or more, preferably 150 μm or less, still more preferably 130 μm or less. The thickness of the film is the total thickness when the film is a laminated film composed of a plurality of layers. When the thickness of the film is in the above range, it is preferable in terms of durability and flexibility of the film.

Here, the water vapor transmittance is a value measured at a thickness equivalent to 100 μm in an environment of 40 ° C. and a relative humidity of 90%. For example, transportation / industrial packaging technology (supervised by Shinichi Mizuguchi, Fuji Techno Systems Co., Ltd.) From the materials listed in (issued), those that satisfy the above water vapor permeability can also be used.

The volume of the composition that can be accommodated is not limited to the following, but is preferably 100 to 5000 mL, the lower limit is preferably 200 mL or more, more preferably 500 mL or more, the upper limit is preferably 3000 mL or less, and more preferably 2000 mL or less. 1000 mL or less is more preferable. When the capacity is within the above range, the curability, storage stability, and ejection stability can all be further improved.

Here, an ink cartridge which is an example of the housing of the present embodiment will be described. FIG. 1 is an exploded perspective view showing an ink cartridge 40. The ink cartridge 40 includes an ink pack 70 filled with ink, a cartridge case 72 including a main body case 76 that houses and protects the ink pack 70, and a lid 78, and the ink pack 70 includes an ink supply port 74. The main body case 76 includes a notch 80 and a groove 86, and the lid 78 includes a holding portion 82 and a hook portion 84. The above-mentioned materials can be used as the material of the ink pack. In the ink cartridge 40, the ink pack 70 is housed in the main body case 76 and the lid portion 84, and at that time, the ink supply port 74 is fitted into the notch portion 80, and then the holding portion 82 and the notch portion 80 are used. It is fixed by being pinched. Further, the main body case 76 and the lid portion 84 are sealed by fitting the hook portion 84 into the groove portion 86.

As described above, according to the present embodiment, it is possible to provide an accommodating body containing an ultraviolet curable composition having excellent curability, suppressing the precipitation of foreign substances, and having high production efficiency thereof.

The entire container or at least a portion of the container may be further housed and sealed in a bag-shaped member. This makes it possible to more effectively and surely prevent an increase in the amount of water in the composition. As the bag-shaped member, a bag-shaped film constituting the above-mentioned container can be used. Further, the water vapor transmittance of the film is preferably 30 g / ^m 2.24 hrs or less, more preferably 15 g / ^m 2.24 hrs or less, as in the case where the container is a pack, and 10 g / m. It is ^more preferably 2.24 hrs or less, and particularly preferably 5.0 g / ^m 2.24 hrs or less.

(Inkjet device and inkjet method)
The inkjet device of the present embodiment is a device including an inkjet head that uses the above-mentioned inkjet composition and an inclusion body and ejects the composition by an inkjet method. Further, the inkjet method of the present embodiment includes a ejection step of ejecting the composition from the inkjet head. The inkjet method of the present embodiment has a curing step of ejecting the composition to an ejected body (for example, a recording medium) and curing the composition adhering to the ejected body by irradiation with ultraviolet rays. You may. Further, the inkjet device of the present embodiment may include an irradiation device used in the curing step. In the irradiation step, it is preferable to use a metal halide lamp, a mercury lamp, an ultraviolet light emitting diode or the like as an ultraviolet light source, and among these, an ultraviolet light emitting diode is more preferable from the viewpoint of miniaturization and power saving. As the ultraviolet light emitting diode, a diode having an emission peak wavelength preferably in the range of 360 to 420 nm is preferable because it is easily available. Further, the irradiation energy of ultraviolet rays in the curing step is preferably 100 to 1000 mJ / cm ² and more preferably 800 mJ / cm ² or less from the viewpoint of sufficiently curing the composition and shortening the curing process. 600 mJ / cm ² or less is more preferable, 200 mJ / cm ² or more is more preferable, and 300 mJ / cm ² or more is further preferable. In the inkjet apparatus and the inkjet method of the present embodiment, configurations other than the above are not particularly limited. For example, as other configurations, conventionally known configurations may be provided. According to the inkjet recording apparatus and the inkjet recording method of the present embodiment, not only the ink jet composition for ink jet is excellent in curability, but also foreign matter can be suppressed from being deposited in the composition, so that the ink composition is also excellent in ejection stability. It becomes. Further, particularly when the composition contains a polymerizable compound having a vinyl ether group, the composition is excellent in storage stability even though the composition is cured by irradiation with ultraviolet rays. Furthermore, when the composition contains a polymerizable compound having a vinyl ether group, the viscosity of the composition can be reduced, so that the discharge stability can be further improved from such a viewpoint.

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

[Material for UV curable composition]
The main materials for the UV curable composition used in the following Examples and Comparative Examples are as follows.
[Color material]
P. I. Pigment Blue 15: 4
[Polymerizable compound]
VEEA (2- (2-vinyloxyethoxy) ethyl acrylate, manufactured by Nippon Shokubai Co., Ltd., number of functional groups 1)
PEA (phenoxyethyl acrylate, manufactured by Osaka Organic Chemical Co., Ltd., number of functional groups 1)
DPGDA (dipropylene glycol diacrylate, manufactured by Sartmer, number of functional groups 2)
SR444 (pentaerythritol triacrylate, manufactured by Nippon Kayaku Co., Ltd., number of functional groups 3)
[Polymer initiator]
IRGACURE TPO (BASF product name, solid content 100% by mass)
IRGACURE 369 (trade name manufactured by BASF, solid content 100% by mass)
KAYACURE DETX (Product name manufactured by Nippon Kayaku Co., Ltd., solid content 100% by mass)
[Dispersant]
solspecs36000 (trade name manufactured by Lubrizole)
[Polymerization inhibitor]
MEHQ (hydroquinone monomethyl ether, manufactured by Tokyo Chemical Industry Co., Ltd.)

(Examples 1 to 20, Comparative Examples 1 to 9)
[Preparation of UV curable composition]
Each material was mixed with the composition (mass%) shown in Tables 1 to 3 below and sufficiently stirred to obtain each ultraviolet curable composition. Each of the polymerizable compounds was used in each Example and Comparative Example so that the water content of the composition was the amount of each example shown in Tables 1 to 3 as in the evaluation of the dehydration step efficiency described later. The polymerizable compound was distilled and purified once or multiple times before use, or pure water was added to the composition to adjust the water content to the values shown in Tables 1 to 3. As for the pigments, various pigments having different manufacturing methods are further washed with pure water once or multiple times to prepare pigments having different cleaning conditions, and any of the pigments is used in each example. Then, the content of the metal element in the composition was set to the value of each example shown in Tables 1 to 3.

(Measurement of water content)
Using a moisture meter (product name "Automatic Heated Vaporized Moisture Measurement System AQS-2210" manufactured by Hiranuma Sangyo Co., Ltd.), the moisture content in the ultraviolet curable composition was measured by the Karl Fisher coulometric method. The results are shown in Tables 1 to 3 (based on mass).

(Measurement of metal element content)
The content of each metal element in the ultraviolet curable composition was measured by ICP emission spectroscopic analysis method (ICP emission spectroscopy analyzer, manufactured by Hitachi High-Tech). The results are shown in Tables 1 to 3 (mass ppm).

(Evaluation of dehydration process efficiency (manufacturing efficiency))
Using each polymerizable compound obtained by a conventional method, an ultraviolet curable composition having the composition shown in Tables 1 to 3 was prepared, and the water content thereof was measured. When the water content was equal to or less than the values shown in Tables 1 to 3, pure water was added to the composition as needed to adjust the water content to the values in Tables 1 to 3. On the other hand, when the water content exceeded the values shown in Tables 1 to 3, the polymerizable compound was purified by distillation once using a rotary evaporator. Using each polymerizable compound after distillation and purification, an ultraviolet curable composition having the composition shown in Tables 1 to 3 was prepared, and the water content thereof was measured. In this way, distillation purification, preparation of the composition, and measurement of the water content were repeated until the water content values of each example in Tables 1 to 3 were reached. Then, it was evaluated as follows based on the number of distillation purifications. The smaller the number of distillation purifications, the higher the dehydration process efficiency (manufacturing efficiency). The results are shown in Tables 1 to 3.
◯: 2 times or less. Alternatively, distillation purification was not required.
Δ: 3 to 4 times.
×: 5 times or more.

(Evaluation of curability)
Using a bar coater, the ultraviolet curable composition was applied onto a PET film (PET50A PL thin [trade name], manufactured by Lintec Corporation) to prepare a coating film having a thickness of 14 μm. Then, the coating film was cured by irradiating with ultraviolet rays having an irradiation intensity of 1100 mW / cm ² and a wavelength of 395 nm. The cured coating film (cured film) was rubbed 10 times with a weight of 100 g using a cotton swab, and the curing energy (irradiation energy) at the time when no scratches were obtained was obtained.
The irradiation energy [mJ / cm ² ] was obtained by measuring the irradiation intensity [mW / cm ² ] on the irradiated surface irradiated from the light source and multiplying this by the irradiation duration [s]. The irradiation intensity was measured using an ultraviolet intensity meter UM-10 and a light receiving unit UM-400 (both manufactured by Konica Minolta SENSING, INC.). Based on the result of irradiation intensity, it was evaluated according to the following evaluation criteria. The results are shown in Tables 1 to 3.
⊚: 250 mJ / cm ² or less ○: 250 mJ / cm ² or more and 350 mJ / cm ² or less △: 350 mJ / cm ² or more and 400 mJ / cm ² or less ×: 400 mJ / cm ² or more

(Evaluation of discharge stability (suppression of foreign matter precipitation))
A head having 360 nozzles is fixed to the upper part, a PET film (part number "PET50 K2411 PAT1E", manufactured by Lintec Corporation) is conveyed under the nozzles of the head at 15 m / min, and 10 kHz is transferred from 180 nozzles to the PET film. The ultraviolet curable composition was ejected and continuous printing was performed. At the same time as printing, an image was formed by irradiating the ink composition attached to the PET film with an LED having an emission wavelength peak of 395 nm. Every 5 minutes from the start of ejection, it was visually confirmed whether or not the ultraviolet curable composition was ejected from all the nozzles, and the evaluation was made according to the following evaluation criteria. The results are shown in Tables 1 to 3. Further, when the ultraviolet curable composition was observed with an optical microscope, it was found that particles having a particle size of 3 μm or more were present in those evaluated for ejection stability of Δ or ×. On the other hand, in the case where the discharge stability was evaluated as ⊚ or ◯, the presence of particles having a particle size of 3 μm or more was not confirmed.
⊚: Nozzle omission for 60 minutes or more.
◯: Nozzle is missing in 30 minutes or more and less than 60 minutes.
Δ: Nozzle is missing in 15 minutes or more and less than 30 minutes.
×: Nozzle is missing in less than 15 minutes.

(Evaluation of storage stability)
After the ultraviolet curable composition was contained in a glass bottle, the glass bottle was sealed and stored at 60 ° C. for 2 weeks. The viscosity of the UV-curable composition before and after storage at 20 ° C. was measured with a viscometer manufactured by phisica, and the viscosity of the UV-curable composition after storage was compared with the viscosity of the UV-curable composition before storage. Was calculated by what percentage increased, that is, by what percentage the viscosity increased. Based on the results, evaluation was made according to the following evaluation criteria. The results are shown in Tables 1 to 3.
⊚: Thickening is less than 5%.
◯: Thickening is 5% or more and less than 10%.
Δ: Thickness increase is 10% or more and less than 15%.
×: Thickening is 15% or more.

(Evaluation of the durability of the containment body)
Two films were cut into rectangles of the same size, and the three sides of the two films were heat-sealed to prepare a pack. The film is based on either film 1 (material: high-density polyethylene, plasticizer: diethyl adipate, thickness: 100 μm) or film 2 (material: high-density polyethylene, plasticizer: none, thickness: 100 μm). An aluminum vapor-deposited film (thickness: 12 μm) was formed on the base material and used as a laminated film. Two laminated films were laminated with the aluminum vapor deposition film side facing outward, and three sides were heat-sealed to form a pack. The pack was filled with 700 mL of the composition and the remaining sides were heat-sealed to keep out air and the pack was sealed. An aluminum-deposited film (thickness: 12 μm) was formed on the outer side of the pack to obtain an aluminum-deposited pack filled with an ultraviolet curable composition. When the water vapor transmittance of the laminated film was measured, it was 0.5 g / m 2.24 hrs for both the film 1 and the film ² . Next, an enclosure was prepared in which a container (a pack filled with the composition prepared above and sealed) was housed in an exterior (shape: rectangular parallelepiped, material: polycarbonate, dimensions: width 10 x length 30 x height 4 cm). The housing was fixed to the table in the horizontal orientation, and the table was reciprocated a predetermined number of times in the direction of the long side of the housing at a distance of 30 cm and a speed of 20 cm / s. The number of round trips at the time when an abnormality was confirmed due to a crack or tear on the surface of the container (pack) was recorded, and the evaluation was performed according to the following evaluation criteria based on the number of round trips. The results are shown in Tables 1 to 3.
⊚: There was no abnormality in the container even after 1500 round trips.
X: An abnormality occurred in the container with less than 1500 round trips.

Further, although not described in the table, the composition is the same as that of Example 1 except that the base material of the film 1 that does not form the aluminum vapor-deposited film is used as a film to form a pack. Obtained a packed pack. The water vapor transmittance of the film substrate was measured and found to be 40 g / ^m 2.24 hrs. This pack and the pack prepared in Example 1 were stored for 6 months in an environment of a temperature of 40 ° C. and a relative humidity of 90%, and the water content of the ultraviolet curable composition after storage was measured. The water content of the pack (pack having an aluminum vapor deposition film) was 1% by mass or less, but that of the pack (pack without an aluminum vapor deposition film) was more than 1% by mass. From this, it was found that the water vapor transmittance of the film constituting the pack is preferably 30 g / ^m 2.24 hrs or less.

By comparing Examples 1 and 6 to 14 with Comparative Examples 1 and 2, it was found that when the content of a specific metal element is 10 mass ppm or more, the curability is particularly excellent. Further, by comparison between Examples 1 and 15 to 19 and Comparative Examples 3 and 4, when the content of each of the specific metal elements is 250 mass ppm or less, the discharge stability (suppression of foreign matter precipitation) is particularly excellent and storage. It was found that it also tends to be excellent in stability. Further, in comparison with Examples 1 to 5 and Comparative Examples 5 to 9, the water content is 0.05% by mass or more and 1.0% by mass or less, so that the dehydration process efficiency (manufacturing efficiency) and storage stability are particularly stable. It was found to be excellent in properties, curability and ejection stability (suppression of foreign matter precipitation).

40 ... ink cartridge, 70 ... ink pack, 72 ... cartridge case, 74 ... ink supply port, 76 ... main body case, 78 ... lid, 80 ... notch, 82 ... holding part, 84 ... hook, 86 ... groove ..

Claims (13)

An ultraviolet curable composition containing a polymerizable compound and contained in an accommodating body.
The water content is 0.05% by mass or more and 0.5% by mass or less with respect to the total amount of the ultraviolet curable composition.
The content of one or more metal elements selected from the group consisting of Na, K, Ca, and Zn is 100 mass ppm or more.
Moreover, the content of the metal element contained in the group consisting of Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, Al and Zr is 250 mass ppm or less, respectively.
A monofunctional (meth) acrylate having a vinyl ether group, a monofunctional (meth) acrylate not a monofunctional (meth) acrylate having a vinyl ether group, a bifunctional (meth) acrylate, and a trifunctional or higher (meth) acrylate . Contains,
Radical polymerization type UV curable composition. The ultraviolet curable composition according to claim 1, which is an inkjet composition. The ultraviolet curable composition according to claim 1 or 2, which contains the one or more metal elements in the form of at least one of a metal ion and a metal salt. The ultraviolet curable composition according to any one of claims 1 to 3, wherein the water content is 0.05% by mass or more and 0.2% by mass or less. The ultraviolet curable composition according to any one of claims 1 to 4, which contains a photoradical polymerization initiator. Any one of claims 1 to 5, wherein the polymerizable compound contains 10 to 60% by mass of a monofunctional (meth) acrylate that is not a monofunctional (meth) acrylate having a vinyl ether group with respect to the total amount of the composition. The UV curable composition according to the section. The ultraviolet curable composition according to any one of claims 1 to 4, which contains an acylphosphine oxide-based photopolymerization initiator as a photoradical polymerization initiator. Of the metal elements contained in the group consisting of Li, Na, K, Ag, Mg, Ca, Ba, Zn, Fe, Sn, Al and Zr, the content is relative to the total amount of the ultraviolet curable composition. The ultraviolet curable composition according to any one of claims 1 to 7, wherein the amount of 10 to 250 mass ppm of the metal element is 3 or more. A container containing the ultraviolet curable composition according to any one of claims 1 to 8. A container comprising a container containing a fatty acid ester as a plasticizer and the ultraviolet curable composition according to any one of claims 1 to 9 filled in the container. A container filled with the UV curable composition is provided.
Either (1) the container is a pack using a film , or (2) the bag-shaped member having a bag-shaped film is provided and the container is housed in the bag-shaped member .
The container according to claim 9 or 10, wherein the film is provided with a layer composed of at least one of a metal and a metal compound on the film. A discharge step of ejecting the ultraviolet curable composition according to any one of claims 1 to 8 by an inkjet method.
An inkjet method comprising a curing step of irradiating an ultraviolet curable composition adhered to an object to be ejected by the ejection step with ultraviolet rays to cure the composition. An ultraviolet light emitting diode is used as the light source.
The inkjet method according to claim 12, wherein the irradiation energy of the irradiation is 100 to 1000 mJ / cm ² .

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