Laminated tube container

Abstract

To provide a laminated tube container with which ingredients in digital ink can be suppressed from migrating to the inside of the tube container body.SOLUTION: A laminated injection molded tube container comprises: a tube container body containing low density polyethylene; and an oxygen barrier layer formed from cationically polymerizable photocurable composition and a digital ink layer contained in this order from the tube container body side on the outside of the tube container body. The cationically polymerizable photocurable composition contains: cationically polymerizable ingredients containing alicyclic epoxy compound; and a cationically polymerizable initiator. The tube container body includes: a head part composed of a mouth part 1 and a shoulder part 3; and a body part 2 connected to the shoulder part. The head part and the body part are integrally molded.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminated tubular container. [Background technology]

[0002] Tube containers having a head portion consisting of a mouth portion and a shoulder portion and a body portion connected to the shoulder portion have been used conventionally as containers for liquid or cream-like medicines, quasi-drugs, cosmetics, and the like.

[0003] Such tube container bodies (hereinafter, tube containers without a printed layer or the like will also be referred to as "tube container bodies") are manufactured by extrusion molding, which allows for easy formation of tube container bodies in the desired shape. Meanwhile, it is also known that a tube container body can be manufactured by injection molding (for example, Patent Document 1). An injection-molded tube container body is formed by forming a molded body having a head portion consisting of a mouth portion and a shoulder portion and a body portion connected to the shoulder portion using a specified mold, and then sealing the end of the body portion opposite to the head side.

[0004] A printed layer is often provided on the tube container body as described above for the purpose of improving the design of the external appearance and for indicating the contents. In recent years, the formation of such a printed layer by digital printing has been considered because this allows small-lot production, does not require printing plates, and can accommodate a wide variety of designs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5941459 Summary of the Invention [Problem to be solved by the invention]

[0006] Tube containers used for liquid or cream-like medicines, quasi-drugs, cosmetics, etc. are usually used by squeezing the container to push out the contents, so they are required to be highly flexible. For this reason, the thickness of the body of the tube container (the part that holds the contents) is usually required to be thin, about 1.0 mm or less.

[0007] Incidentally, the digital ink used in the above-mentioned digital printing is usually a composition with extremely low viscosity, since it must pass through a head with an extremely small diameter. It was found that when such low-viscosity digital ink is printed onto a thin tube container body, components in the digital ink (particularly what is thought to be a polymerization initiator) migrate into the tube container body, and further, the components pass through the thin tube container and migrate (migrate) to the inner surface of the tube container body.

[0008] If such migration occurs, the contents of the tube container will mix with the components in the digital ink, contaminating the contents. Therefore, it is necessary to suppress this migration in order to prevent deterioration of the performance of the contents and to ensure safety when using the contents.

[0009] As a method of suppressing the migration, the use of a low-migration ink in which the amount of polymerization initiator (photoinitiator) in the digital ink is reduced has been considered; however, it has been found that even when such a low-migration ink is used, in the case of a thin tube container body such as that described above, migration to the inner surface of the container body cannot be sufficiently suppressed.

[0010] Another method of suppressing the migration is to provide another layer between the tube container body and the digital ink layer. However, it is generally believed that if such another layer is present, cracks will occur in the other layer when squeezed as described above, and these cracks will also cause cracks in the digital ink layer, resulting in the other layer and the digital ink layer peeling off.

[0011] The present invention has been made in consideration of the above-mentioned problems, and has an objective of providing a laminated tube container in which the components in digital ink are prevented from migrating to the inner surface of the tube container body. [Means for solving the problem]

[0012] As a result of intensive research by the present inventors to solve the above problems, they found that the above problems can be solved by the following configuration examples, and thus completed the present invention. A configuration example of the present invention is as follows.

[0013] [1] A tube container body containing low-density polyethylene; The laminated tube container includes, on the outside of the tube container body, an oxygen barrier layer formed from a cationically polymerizable photocurable composition, and a digital ink layer, in this order from the tube container body side.

[0014] [2] The laminated tube container according to [1], wherein the cationically polymerizable photocurable composition is a composition containing a cationically polymerizable component (a) including an alicyclic epoxy compound and a cationic polymerization initiator (b).

[0015] [3] The tube container body includes a head portion having a mouth portion and a shoulder portion, and a body portion connected to the shoulder portion, The laminated tube container according to [1] or [2], which is an injection-molded tube container in which the head and body are integrally molded.

[0016] [4] The laminated tube container according to [3], wherein the thickness of the body of the tube container body is 1.0 mm or less.

[0017] [5] The laminated tubular container according to any one of [1] to [4], wherein the oxygen barrier layer has a thickness of 7 to 12 μm. Effect of the Invention

[0018] According to the present invention, it is possible to provide a laminated tube container in which the components in the digital ink are suppressed from migrating to the inner surface of the tube container body. In particular, according to the present invention, a laminated tube container can be provided in which, even when a digital ink layer is formed on a tube container body having a body thickness of 1.0 mm or less and excellent flexibility, migration of components in the digital ink to the inner surface of the tube container body is suppressed. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic diagram showing an example of a side view of a laminated tube container (or a tube container body) according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] <Laminated tube container> The laminated tube container according to the present invention (hereinafter also referred to as "the container") has a tube container body containing low-density polyethylene, The outside of the tube container body includes, from the tube container body side, an oxygen barrier layer formed from a cationically polymerizable photocurable composition, and a digital ink layer, in this order.

[0021] The uses of the present container are not particularly limited, but include uses for using, storing, transporting, etc., liquid or cream-like medicines, quasi-drugs, cosmetics, food, construction, civil engineering, agricultural materials, etc., and more preferably uses for using, storing, transporting, etc., liquid foundation, cream, facial cleanser, etc.

[0022] <Tube container body> The tube container body is not particularly limited as long as it contains low density polyethylene. The low-density polyethylene may be a resin derived from biomass or a resin derived from fossil fuels, but is preferably a resin that can be injection molded. The low-density polyethylene contained in the tube container body may be of one type alone or of two or more types.

[0023] The tube container body may contain, as necessary, components such as thermoplastic resins, antioxidants, stabilizers such as heat stabilizers, light stabilizers, and weather stabilizers, ultraviolet scattering agents, anti-slip agents, anti-fogging agents, colorants, dispersants, fillers, antistatic agents, lubricants, softeners, plasticizers, and processing aids, within the scope that does not impair the effects of the present invention. The tube container body may contain one kind of these other components alone, or may contain two or more kinds of them.

[0024] The tube container body is not particularly limited, but is preferably an injection-molded tube container body formed by injection molding, from the viewpoint that a container body of a desired shape can be easily formed. The tube container body generally comprises a head portion consisting of a shoulder portion 3 and a mouth portion 1, and a body portion 2 connected to the shoulder portion 3, as shown in FIG.

[0025] The thickness of the body of the tube container body may be appropriately selected depending on the desired application, but from the viewpoints that when the container is used by squeezing it to push out the contents, squeezing can be easily performed and a container with excellent flexibility can be easily obtained, etc., the thickness is preferably 1.0 mm or less, more preferably 0.5 to 1.0 mm, even more preferably 0.5 to 0.9 mm, and particularly preferably 0.5 to 0.8 mm. A tube container body containing low-density polyethylene is preferred because it is easy to make an injection-molded tube container body with a body thickness of this kind, and even if the body thickness is such, the injection-molded tube container body has excellent injection moldability, flexibility, and stress cracking resistance.

[0026] The length of the body of the tube container body may also be appropriately selected depending on the desired application, but is preferably 10 cm or more, more preferably 11 to 20 cm, and particularly preferably 14 to 16 cm. A tube container body containing low-density polyethylene can be easily made into an injection-molded tube container body of this length, and even if the body portion has this length, it is preferable because the injection-molded tube container body has excellent injection moldability, flexibility, and stress cracking resistance.

[0027] [Manufacturing method of tube container body] The tube container body can be manufactured by injection molding each of the components that make up the tube container body. When a plurality of kinds of components are used, it is preferable to mix these components and form a composition, and then, or while forming the composition, to injection mold the composition.

[0028] The method for forming the composition is not particularly limited, but a method in which the components are melt-kneaded using a conventionally known device, specifically, a single-screw extruder, a twin-screw extruder, a kneader, a mixer, a two-roll mill, or the like, is preferred.

[0029] The MFR of the raw material for the tube container body, measured based on JIS K 7210 (190°C, 21.18 N load), is preferably 15 to 80 g / 10 min, since this provides an injection-molded tube container body that is excellent in moldability, particularly injection moldability, and has excellent mechanical strength such as impact resistance.

[0030] The injection molding conditions include an injection speed of preferably 60 mm / s or less, more preferably 50 mm / s or less, and an injection temperature (cylinder temperature) of preferably 250°C or less, more preferably 240°C or less, and particularly preferably 230°C or less. The fact that the tube container body having the above shape can be injection molded under such conditions means that the material has injection moldability sufficient for practical use. If the MFR of the raw material of the tube container body is 1.0 g / 10 min or more, the tube container body having the above shape can be injection molded under such conditions. Even when produced under such injection molding conditions, the tube container body containing low-density polyethylene has the above-mentioned shape and is excellent in stress cracking resistance.

[0031] The tube container body is preferably an injection molded tube container body in which the head and body are integrally molded. By molding the head and body as a single piece, the process of combining the head and body can be omitted, which eliminates the need for complicated and cumbersome processes, reducing costs, and is preferable because it is less likely to cause quality degradation such as adhesion of foreign matter or a decrease in the welding strength between the head and body.

[0032] Specifically, such an integrally molded injection molded tube container body can be manufactured by the following method. Specifically, an injection molding mold capable of integrally forming the mouth portion, shoulder portion, and body portion can be used to inject, for example, each component constituting the tube container body or the composition, to obtain an integrally molded injection-molded tube container body.

[0033] During the injection, it is preferable to inject each component constituting the tubular container body or the composition into the cavity through at least two or more gates. By using two or more gates, injection can be performed with uniform pressure, so that a tubular container body of a desired shape can be easily obtained.

[0034] The integrally molded body of the head and body thus obtained can be made into a tube container body by welding the end of the body opposite to the head side. As the welding method, any conventionally known welding method such as hot air welding, ultrasonic welding, heat sealing, etc. can be used without any restrictions.

[0035] <Oxygen barrier layer> The oxygen barrier layer is not particularly limited as long as it is a layer formed from a cationically polymerizable photocurable composition. It is believed that the oxygen barrier layer formed from such a cationic polymerizable photocurable composition will continue to undergo a curing reaction over time even after curing by light irradiation. Therefore, in this container, by providing such an oxygen barrier layer between the tube container body and the digital ink layer, even if migration of a component in the digital ink, such as a polymerization initiator, from the digital ink layer to the oxygen barrier layer occurs, the component is used in the curing reaction in the oxygen barrier layer, and therefore it is believed that migration of the component in the digital ink to the inner surface of the tube container body can be sufficiently suppressed.

[0036] The oxygen barrier layer is usually formed on the body of the container. In this case, the oxygen barrier layer may be formed on the entire surface of the body, or may be formed on only a part of the body. The oxygen barrier layer contained in the present container may be two or more layers, but typically is one layer.

[0037] The oxygen barrier layer is preferably a layer obtained by photocuring a cationic polymerizable photocurable composition containing a cationic polymerizable component (a) including an alicyclic epoxy compound and a cationic polymerization initiator (b), in view of the fact that the oxygen barrier layer has excellent oxygen barrier properties and adhesion to the tube container body, and is less likely to crack.

[0038] [Cationically polymerizable component (a)] The cationic polymerizable component (a) contains an alicyclic epoxy compound (hereinafter also referred to as "compound (a1)"). The component (a) may consist of only the compound (a1), or may contain other components such as an aliphatic epoxy resin (a2).

[0039] [Alicyclic epoxy compounds] Examples of the compound (a1) include polyglycidyl ethers of polyhydric alcohols having at least one aliphatic ring, and cyclohexene oxide- or cyclopentene oxide-containing compounds obtained by epoxidizing cyclohexene- or cyclopentene ring-containing compounds with an oxidizing agent. Specific examples of the compound (a1) include hydrogenated bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate, 3,4-epoxy-1-methylcyclohexyl-3,4-epoxy-1-methylhexane carboxylate, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxycyclohexane carboxylate, 3,4-epoxy-3-methylcyclohexylmethyl-3,4-epoxy-3-methylcyclohexane carboxylate, 3,4-epoxy-5-methylcyclohexylmethyl-3,4-epoxy-5-methylcyclohexane carboxylate, 2-(3,4-epoxycyclohexyl-5, 5-spiro-3,4-epoxy)cyclohexane-metadioxane, bis(3,4-epoxycyclohexylmethyl)adipate, 3,4-epoxy-6-methylcyclohexylcarboxylate, methylene bis(3,4-epoxycyclohexane), dicyclopentadiene diepoxide, ethylene bis(3,4-epoxycyclohexanecarboxylate), dioctyl epoxyhexahydrophthalate, di-2-ethylhexyl epoxyhexahydrophthalate, 1-epoxyethyl-3,4-epoxycyclohexane, 1,2-epoxy-2-2 epoxyethylcyclohexane, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate. The compound (a1) contained in the component (a) may be one type or two or more types.

[0040] Examples of commercially available products that can be suitably used as the compound (a1) include Celloxide 2021, Celloxide 2021P, Celloxide 2081, Celloxide 2083, Celloxide 2085, Celloxide 2000, Celloxide 3000, Cyclomer A200, Cyclomer M100, Cyclomer M101, Epolead GT-301, Epolead GT-302, Epolead 401, Epolead 403, ETHB, and Epolead HD300 (all manufactured by Daicel Corporation); KRM-2110 and KRM-2199 (all manufactured by ADEKA Corporation); and the like.

[0041] The compound (a1) is preferably an epoxy compound having a cyclohexene oxide structure in terms of curability (curing speed).

[0042] The content of the compound (a1) is preferably 97 to 100% by mass, more preferably 98 to 99% by mass, relative to 100% by mass of the component (a), from the viewpoints of easily obtaining an oxygen barrier layer that is excellent in oxygen barrier properties and adhesion to the tube container body and is less susceptible to cracking.

[0043] [Aliphatic epoxy compound (a2)] The component (a) may contain an aliphatic epoxy compound (a2). By using the compound (a1) and the compound (a2) in combination, it is possible to reduce the viscosity of the resulting composition, and it is possible to easily obtain a cationic polymerizable photocurable composition having excellent coatability.

[0044] Examples of the compound (a2) include polyglycidyl ethers of aliphatic polyhydric alcohols or their alkylene oxide adducts; polyglycidyl esters of aliphatic long-chain polybasic acids; homopolymers of glycidyl acrylate or glycidyl methacrylate; and copolymers of glycidyl acrylate or glycidyl methacrylate with other vinyl monomers. Specific examples of the compound (a2) include glycidyl ethers of polyhydric alcohols such as 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, tetraglycidyl ether of sorbitol, hexaglycidyl ether of dipentaerythritol, diglycidyl ether of polyethylene glycol, and diglycidyl ether of polypropylene glycol; aliphatic polyhydric alcohols such as propylene glycol, trimethylolpropane, and glycerin; Examples of such glycidyl ethers include polyglycidyl ethers of polyether polyols obtained by adding one or more alkylene oxides to coal; diglycidyl esters of aliphatic long-chain dibasic acids; monoglycidyl ethers of aliphatic higher alcohols, and monoglycidyl ethers of polyether alcohols obtained by adding alkylene oxides to phenol, cresol, and butylphenol; glycidyl esters of higher fatty acids; epoxidized soybean oil; octyl epoxy stearate; butyl epoxy stearate; and epoxidized polybutadiene. When the component (a) contains a compound (a2), the compound (a2) contained therein may be one type or two or more types.

[0045] Commercially available products that can be suitably used as the compound (a2) include ED-505 and ED-506 (both manufactured by ADEKA CORPORATION); Epolight M-1230, Epolight EHDG-L, Epolight 40E, Epolight 100E, Epolight 200E, Epolight 400E, Epolight 70P, Epolight 200P, Epolight 400P, Epolight 1500NP, Epolight 1600, Epolight 80MF, Epolight 100MF, Epolight 4000, and Epolight FR-1500 (all manufactured by Kyoeisha Chemical Co., Ltd.); Santot ST0000, YD-716, YH-300, PG-202, PG-207, YD-172, YDPN638 (all manufactured by Nippon Steel Chemical & Material Co., Ltd.); Denacol EX321, Denacol EX313, Denacol 314, Denacol EX-411, EM-150 (all manufactured by Nagase ChemteX Corporation); EPPN-201, EOCN-1020, EPPN-501H (all manufactured by Nippon Kayaku Co., Ltd.); EHPE-3150, EHPE-3150CE (all manufactured by Daicel Corporation); and the like.

[0046] [Other compounds] The component (a) may contain, in addition to the compounds (a1) and (a2), other compounds that undergo a polymerization or crosslinking reaction upon irradiation with light. Examples of such other compounds include aromatic epoxy compounds such as polyglycidyl ethers of polyhydric phenols having at least one aromatic ring (e.g., bisphenol A, bisphenol F) or alkylene oxide adducts thereof; oxetane compounds such as Aron Oxetane OXT-101, OXT-121, OXT-221, OXT-212, and OXT-211 (all manufactured by Toagosei Co., Ltd.), Ethanacol EHO, OXBP, OXTP, and OXMA (all manufactured by Ube Industries, Ltd.); oxolane compounds such as tetrahydrofuran and 2,3-dimethyltetrahydrofuran; cyclic acetal compounds such as trioxane, 1,3-dioxolane, and 1,3,6-trioxanecyclooctane; cyclic lactone compounds such as β-propiolactone and ε-caprolactone; ethylene sulfide, thioepichlorohydrin, and the like. thiirane compounds such as 1,3-propyne sulfide, 3,3-dimethylthiethane, and cyclic thioether compounds such as tetrahydrothiophene derivatives; vinyl ether compounds such as ethylene glycol divinyl ether, alkyl vinyl ether, 2-chloroethyl vinyl ether, 2-hydroxyethyl vinyl ether, triethylene glycol divinyl ether, 1,4-cyclohexanedimethanol divinyl ether, hydroxybutyl vinyl ether, and propylene glycol propenyl ether; spiro orthoester compounds obtained by the reaction of an epoxy compound with a lactone; ethylenically unsaturated compounds such as styrene, vinylcyclohexene, isobutylene, and polybutadiene, and derivatives thereof; and these may be used alone or in combination. Among these, aromatic epoxy compounds and oxetane compounds are preferred because they are easily available and easy to handle.

[0047] [Cationic Polymerization Initiator (b)] The polymerization initiator (b) is not particularly limited as long as it is a compound that can be activated by light irradiation, but is preferably a double salt, which is an onium salt that releases a Lewis acid by irradiation with ultraviolet light, or a derivative thereof. The polymerization initiator (b) contained in the cationically polymerizable photocurable composition may be one type or two or more types.

[0048] Specific examples of the polymerization initiator (b) include those represented by the formula [A] m+ [B] m- Examples of the salt include salts of a cation and an anion represented by the following formula:

[0049] The cation [A] m+ is preferably an onium, the structure of which is, for example, the formula [(R 20 ) a Q] m+ It can be expressed as: Here, R 20 is an organic group having 1 to 60 carbon atoms and may contain any number of atoms other than carbon atoms. a is an integer from 1 to 5. a R 20 may be the same or different, and at least one of them is preferably an organic group having an aromatic ring. Q is an atom or an atomic group selected from the group consisting of S, N, Se, Te, P, As, Sb, Bi, O, I, Br, Cl, F, and N=N. In addition, the cation [A] m+ When the valence of Q in the formula is q, then m=aq (however, N=N is treated as having a valence of 0).

[0050] The anion [B] m- is preferably a halide complex, the structure of which is, for example, the formula [LX b ] m- It can be expressed as: Here, L is a metal or metalloid that is the central atom of the halide complex, specifically, B, P, As, Sb, Fe, Sn, Bi, Al, Ca, In, Ti, Zn, Sc, V, Cr, Mn, Co, etc. X is a halogen atom. b is an integer of 3 to 7. In addition, the anion [B] m- When the valence of L in is p, m = bp.

[0051] The anion [LX b ] m- A specific example of this is tetrakis(pentafluorophenyl)borate (BF4). - , tetrafluoroborate (BF4)- , Hexafluorophosphate (PF6) - , Hexafluoroantimonate (SbF6) - , Hexafluoroarsenate (AsF6) - , Hexachloroantimonate (SbCl6) - Examples include:

[0052] In addition, the anion [B] m- Other preferred examples of the formula [LX b-1 (OH)] m- Examples of the ions include those represented by the following formula: L, X, and b are the same as those described above.

[0053] The anion [B] m- Other examples include the perchlorate ion (ClO4) - Inorganic ions such as fluorosulfonate ion (FSO3) - , sulfonate ions such as toluenesulfonate ion, trinitrobenzenesulfonate ion, camphorsulfonate ion, nonafluorobutanesulfonate ion, and hexadecafluorooctane sulfonate ion; borate ions such as tetraarylborate ion and tetrakis(pentafluorophenyl)borate ion; carboxylate ions such as methanecarboxylate ion, ethanecarboxylate ion, propanecarboxylate ion, butanecarboxylate ion, octanecarboxylate ion, trifluoromethanecarboxylate ion, benzenecarboxylate ion, and p-toluenecarboxylate ion; trifluoromethylsulfite ion (CF3SO3) - ;Methyl sulfate ion (CH3OSO3) - ; bis(trifluoromethanesulfonyl)imide ion; tris(trifluoromethanesulfonyl)methide ion.

[0054] As the polymerization initiator (b), it is particularly preferable to use the following aromatic onium salts (a) to (c). Among these, one kind may be used alone, or two or more kinds may be used.

[0055] (a) Aryl diazonium salts such as phenyl diazonium hexafluorophosphate, 4-methoxyphenyl diazonium hexafluoroantimonate, and 4-methylphenyl diazonium hexafluorophosphate.

[0056] (b) Diaryl iodonium salts such as diphenyl iodonium hexafluoroantimonate, di(4-methylphenyl) iodonium hexafluorophosphate, di(4-tert-butylphenyl) iodonium hexafluorophosphate, and triaryl iodonium tetrakis(pentafluorophenyl)borate.

[0057] (c) Sulfonium salts consisting of a sulfonium cation represented by the following Group I or Group II and a hexafluoroantimony ion or a tetrakis(pentafluorophenyl)borate ion, etc.

[0058] [ka]

[0059] [ka]

[0060] Other preferred examples of the polymerization initiator (b) include (η 5 and mixtures of aluminum complexes such as tris(acetylacetonato)aluminum, tris(ethylacetonatoacetato)aluminum, and tris(salicylaldehyde)aluminum with silanols such as triphenylsilanol.

[0061] As the polymerization initiator (b), among these, from the viewpoints of practical use and photosensitivity, it is preferable to use an aromatic iodonium salt, an aromatic sulfonium salt, or an iron-arene complex, and from the viewpoint of sensitivity, an aromatic sulfonium salt represented by the following formula (V) is more preferable.

[0062] [ka] (R 101 ~R 110 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an ester group having 2 to 10 carbon atoms; R 111 ~R 114 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbon atoms; R 115 represents any one of the substituents selected from the following (α) to (γ), An q- represents a q-valent anion, and p represents the charge neutralizing coefficient.)

[0063] [ka] (R 21 ~R 30 and R 45 ~R 49 each independently represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms; R 31 ~R 34 and R 36 ~R 44 Each of the symbols independently represents a hydrogen atom, a halogen atom, or an organic group having 1 to 10 carbon atoms. In addition, * represents a bond to the adjacent group.)

[0064] R 21 ~R 34 and R 36 ~R 49 Examples of the halogen atom represented by the formula (I) include fluorine, chlorine, bromine, and iodine.

[0065] R 21 ~R 34 and R36 ~R 49Examples of the organic group having 1 to 10 carbon atoms represented by the formula (I) include methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, isobutyl, amyl, isoamyl, t-amyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, ethyloctyl, 2-methoxyethyl, 3-methoxypropyl, 4-methoxybutyl, 2-butoxyethyl, methoxyethoxyethyl, methoxyethoxyethoxyethyl, 3-methoxybutyl, 2-methylthioethyl, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, difluoroethyl, trichloroethyl, dichlorodifluoroethyl, pentafluoroethyl, heptafluoropropyl, nonafluorobutyl, decafluoropentyl, tridecafluorohexyl, pentadecafluoroheptyl, heptadecafluorooctyl, methoxymethyl, 1,2-epoxyethyl, ethyl, methoxyethoxymethyl, methylthiomethyl, ethoxyethyl, butoxymethyl, t-butylthiomethyl, 4-pentenyloxymethyl, trichloroethoxymethyl, bis(2-chloroethoxy)methyl, methoxycyclohexyl, 1-(2-chloroethoxy)ethyl, 1-methyl-1-methoxyethyl, ethyldithioethyl, trimethylsilylethyl, t-butyldimethylsilyloxymethyl, 2-(trimethylsilyl)ethoxymethyl, t-butoxycarbonylmethyl, ethyloxycarbonylmethyl, ethylcarbonylmethyl, t-butoxycarbonylmethyl, acryloyloxyethyl, methacryloyloxyethyl, 2-methyl-2-adamantyloxycarbonylmethyl, acetylethyl, 2-methoxy-1-propenyl, hydroxymethyl, 2-hydroxyethyl, 1-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 3-hydroxybutyl, 4-hydroxybutyl, 1,Examples of the aryloxy groups include 2-dihydroxyethyl, methoxy, ethoxy, propyloxy, isopropyloxy, butyloxy, s-butyloxy, t-butyloxy, isobutyloxy, pentyloxy, isoamyloxy, t-amyloxy, hexyloxy, cyclohexyloxy, cyclohexylmethyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, 2-methoxyethyloxy, 3-methoxypropyloxy, 4-methoxybutyloxy, 2-butoxyethyloxy, methoxyethoxyethyloxy, methoxyethoxyethoxyethyloxy, 3-methoxybutyloxy, 2-methylthioethyloxy, trifluoromethyloxy, methoxycarbonyl, ethoxycarbonyl, isopropyloxycarbonyl, phenoxycarbonyl, acetoxy, propionyloxy, butyryloxy, chloroacetyloxy, dichloroacetyloxy, trichloroacetyloxy, trifluoroacetyloxy, t-butylcarbonyloxy, methoxyacetyloxy, and benzoyloxy.

[0066] Commercially available products that can be suitably used as the polymerization initiator (b) include Cyracure UVI-6970, Cyracure UVI-6974, Cyracure UVI-6976, Cyracure UVI-6990, Cyracure UVI-6992, and Cyracure UVI-950 (all manufactured by Union Carbide Corporation, USA); Irgacure 250, Irgacure 261, Irgacure 270, Irgacure PAG103, Irgacure PAG121, Irgacure PAG203, Irgacure PAG290, Irgacure CGI725, Irgacure CGI1380, Irgacure CGI1907, and Irgacure GSI. D26-1 (all manufactured by BASF); SP-150, SP-151, SP-170, SP-171, SP-172 (all manufactured by ADEKA); DAICAT II (manufactured by Daicel); UVAC1591 (manufactured by Daicel-Allnex); CI-2481, CI-2734, CI-2823, CI-2758 (all manufactured by Nippon Soda); FFC509 (manufactured by 3M); San-Aid SI-45L, San-Aid SI-60L, San-Aid SI-80L, San-Aid SI-100L, San-Aid SI-110L, San-Aid SI-150L and San-Aid SI-180L (all manufactured by Sanshin Chemical Industry Co., Ltd.);BBI-102, BBI-103, BBI-105, BBI-106, BBI-109, BBI-110, BBI-201, BBI, 301, BI-105, DPI-105, DPI- 106, DPI-109, DPI-201, DTS-102, DTS-103, DTS-105, NDS-103, NDS-105, NDS-155, NDS-159, NDS-165, TPS-102, TPS-103, TPS-105, TPS-106, TPS-109, TPS-1000, MDS-103, MDS-105, MDS-109, MDS-205, MPI -103, MPI-105, MPI-106, MPI-109, DS-100, DS-101, MBZ-101, MBZ-201, MBZ-301, NAI-100, NAI-101, N AI-105, NAI-106, NAI-109, NAI-1002, NAI-1003, NAI-1004, NB-101, NB-201, NDI-101, NDI-105, NDI -106, NDI-109, PAI01, PAI-101, PAI-106, PAI-1001, PI-105, PI-106, PI-109, PYR-100, SI-101, SI-1 05, SI-106 and SI-109 (all manufactured by Midori Chemical Co., Ltd.); Kayacure PCI-204, Kayacure PCI-205, Kayacure PCI-615, Kayacure PCI-625, Kayarad220, Kayarad620, PCI-061T, PCI-062T, PCI-020T, PCI-022T (all manufactured by Nippon Kayaku Co., Ltd.); and the like.

[0067] The content of the polymerization initiator (b) is preferably 0.1 to 10 mass% relative to 100 mass% of the cationic polymerizable photocurable composition, from the viewpoints that the resulting cationic polymerizable photocurable composition can be sufficiently cured and an oxygen barrier layer having excellent strength can be easily obtained.

[0068] [Additives] The cationic polymerizable photocurable composition may contain, as necessary, phenol-based, sulfur-based, or phosphorus-based antioxidants; benzotriazole-based, triazine-based, or benzoate-based ultraviolet absorbers; antistatic agents such as cationic surfactants, anionic surfactants, nonionic surfactants, and amphoteric surfactants; flame retardants such as halogen-based compounds, phosphate ester-based compounds, phosphate amide-based compounds, melamine-based compounds, fluororesins, metal oxides, (poly)melamine phosphate, and (poly)piperazine phosphate; hydrocarbon-based, fatty acid-based, aliphatic alcohol-based, aliphatic ester-based, aliphatic amide-based, or metal soap-based lubricants; pigments, carbon black, and the like, so long as the effects of the present invention are not impaired. Various additives may be added, such as colorants; silica (including fumed silica, fine silica, etc.), silica stone, diatomaceous earth, clay, kaolin, silica gel, calcium silicate, sericite, kaolinite, flint, feldspar powder, vermiculite, attapulgite, talc, mica, minnesotite, pyrophyllite, and other silica-based inorganic additives; fillers such as glass fiber and calcium carbonate; crystallization agents such as nucleating agents and crystallization accelerators; silane coupling agents; agents for imparting rubber elasticity such as flexible polymers; chelating agents; sensitizers; other monomers; defoamers; thickeners; leveling agents; plasticizers; polymerization inhibitors; antistatic agents; flow adjusters; coupling agents; adhesion promoters; preservatives and antifungal agents; and pH adjusters. These various additives may be used independently, either individually or in combination of two or more. The total content of these various additives is preferably 50% by mass or less based on 100% by mass of the cationically polymerizable photocurable composition.

[0069] [Method for preparing a cationically polymerizable photocurable composition] The cationic polymerizable photocurable composition can be produced by mixing the above-mentioned components. The mixing method is not particularly limited, and examples thereof include a method of mixing using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three-roll mill.

[0070] [Oxygen Barrier Layer] The thickness of the oxygen barrier layer is preferably 7 to 12 μm, and more preferably 8 to 11 μm, from the viewpoints of being able to further suppress migration from the digital ink layer and to further suppress cracks that may occur in the oxygen barrier layer and further in the digital ink layer.

[0071] The oxygen barrier layer can be formed by applying a cationic polymerizable photocurable composition onto the tube body and curing the composition. The application onto the tube body can be performed by a known means such as a roll coater, a curtain coater, various printing methods, immersion, etc. Alternatively, the cationic polymerizable photocurable composition may be applied onto a supporting substrate to form a film, and then the film may be transferred onto the tube container body.

[0072] Before forming the oxygen barrier layer on the tubular container body, the tubular container body may be subjected to a treatment such as corona discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, or the like.

[0073] The cationic polymerizable photocurable composition can be cured by irradiation with light, preferably with active energy rays such as ultraviolet rays, to a touch-dry state or a solvent-insoluble state usually within 0.1 seconds to several minutes. In the light irradiation, it is preferable to use electromagnetic wave energy having a wavelength of 2000 to 7000 Å, obtained from an ultra-high, high, medium or low pressure mercury lamp, a xenon lamp, a carbon arc lamp, a metal halide lamp, a fluorescent lamp, a tungsten lamp, an excimer lamp, a germicidal lamp, an excimer laser, a nitrogen laser, an argon ion laser, a helium cadmium laser, a helium neon laser, a krypton ion laser, various semiconductor lasers, a YAG laser, a light emitting diode, a CRT light source or the like, or a high energy ray such as an electron beam, an X-ray or a radiation.

[0074] The time for the light irradiation varies depending on the intensity of the light, the thickness of the oxygen barrier layer to be formed, and the composition used, but is usually about 0.1 to 10 seconds. In order to promote the cationic polymerization, heating may be performed as necessary.

[0075] <Digital ink layer> A specific example of the digital ink layer is a layer formed by digitally printing ink.

[0076] The digital ink layer is formed on the oxygen barrier layer. In this case, the digital ink layer may be formed on the entire surface of the oxygen barrier layer, or may be formed on a part of the oxygen barrier layer. The container may contain two or more digital ink layers, but typically contains one.

[0077] The thickness of the digital ink layer is preferably 2 to 16 μm, and more preferably 3 to 6 μm, from the viewpoint that a digital ink layer that is less likely to crack can be easily obtained.

[0078] The ink used to form the digital ink layer is not particularly limited, and any conventionally known ink can be used. However, in order to better demonstrate the effects of the present invention, a solvent-based ink having a low viscosity is preferred. The ink typically contains a polymerizable compound that is polymerized by light or the like, a polymerization initiator, a colorant (e.g., a dye or pigment), and a solvent, and may contain water and the additives described in the oxygen barrier layer as necessary.

[0079] The ink may be a standard type ink in which the amount of polymerization initiator is not adjusted, or a low-migration type ink in which the amount of polymerization initiator is reduced, but the latter is preferred in consideration of the amount of migration onto the inner surface of the tube container body. An example of a low-migration type ink is an ink in which the content of a polymerization initiator in the ink is 5% by mass or less. EXAMPLES

[0080] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0081] [Example 1] Low-density polyethylene (for injection molding, manufactured by Prime Polymer Co., Ltd.) was placed in an injection molding machine and injection molded at 200°C using an injection molding die capable of integrally forming the mouth, shoulder, and body as shown in Figure 1. The end of the body opposite the head side was welded at 350°C to obtain the injection-molded tubular container body shown in Figure 1, in which the head and body were integrally molded. The resulting injection-molded tubular container body had a body thickness of 0.7 mm and a body length of 14.5 cm.

[0082] A cationic polymerizable ultraviolet-curable composition (PPG4511-801 / A (PPG Japan, Inc., containing an alicyclic epoxy compound and a cationic polymerization initiator) was applied to the body of the obtained injection-molded tube container body using a roll coater so that the thickness of the obtained oxygen barrier layer would be 8 μm. Thereafter, the surface to which the composition was applied was exposed to a UV exposure machine with an accumulated light dose of 500 mJ / cm. 2 (Intensity: 600mW / cm 2 ) to form an oxygen barrier layer on the injection molded tube container body.

[0083] Next, black digital ink (TRITRON, low migration type) was digitally printed on the obtained oxygen barrier layer using a digital printing machine so that the film thickness of the obtained digital ink layer was 5 μm, thereby forming a digital ink layer on the oxygen barrier layer and producing a laminated tube container.

[0084] [Comparative Example 1] A black digital ink (TRITRON, standard type) was digitally printed using a digital printing machine onto the injection-molded tube container body obtained in the same manner as in Example 1 so that the film thickness of the resulting digital ink layer was 5 μm. This formed a digital ink layer on the injection-molded tube container body, thereby producing a laminated tube container.

[0085] [Comparative Example 2] The black digital ink used in Example 1 was digitally printed using a digital printing machine onto an injection-molded tube container body obtained in the same manner as in Example 1 so that the resulting digital ink layer had a thickness of 5 μm, thereby forming a digital ink layer on the injection-molded tube container body and producing a laminated tube container.

[0086] [Comparative Example 3] A black digital ink (low migration type, manufactured by AGFA) was digitally printed using a digital printing machine onto the injection molded tube container body obtained in the same manner as in Example 1 so that the film thickness of the resulting digital ink layer was 5 μm. This formed a digital ink layer on the injection molded tube container body, thereby producing a laminated tube container.

[0087] <Migration test> Using the laminated tube containers obtained in Example 1 and Comparative Examples 1 to 3, the components that migrated to the inner surface of the tube container (the surface of the layer farthest from the digital ink layer) were measured by SQTS (Swiss Quality Testing Services), a specialized organization that measures migration. The results are shown in Table 1. Specifically, in accordance with the standards related to migration, Swiss Regulation on Food Contact Materials SR 817.023.21 of 01.05.2017, Commission Regulation (EU) No 10 / 2011 of 14.01.2011, and EN 1186 Materials and articles in contact with foodstuffs - Plastics, May 2002, the inner surfaces of the laminated tube containers obtained in Example 1 and Comparative Examples 1 to 3 were exposed to 95% ethanol at 60°C for 10 days, and the amount of migration (presumably mainly the amount of polymerization initiator used in forming the digital ink layer, which is contained in the ethanol) [mg / dm 2 and mg / kg food] were measured. 2 Migration amount per unit (mg / dm 2 ) corresponds to the amount of migration per kg of food (mg / kg food). In the EU, the migration dose is 10 mg / dm 2 It is required that the daily intake of food containing 50 mg / kg of food or less be less than 60 mg / kg of food.

[0088] [Table 1]

[0089] Due to its color, black digital ink is difficult to cure and is thought to be the one most likely to have polymerization initiator remaining in the resulting digital ink layer. However, according to the present invention, even when such a black digital ink was used, migration was sufficiently suppressed. The laminated tubular container obtained in Example 1 did not crack even when it was crushed so as to push out the contents. [Explanation of symbols]

[0090] 1: Mouth 2: Torso 3: Shoulders

Claims

1. A tube container body including low density polyethylene, The laminated tube container includes, on the outside of the tube container body, an oxygen barrier layer formed from a cationically polymerizable photocurable composition, and a digital ink layer, in this order from the tube container body side.

2. 2. The laminated tube container according to claim 1, wherein the cationically polymerizable photocurable composition is a composition containing a cationically polymerizable component (a) containing an alicyclic epoxy compound and a cationic polymerization initiator (b).

3. The tube container body includes a head portion having a mouth portion and a shoulder portion, and a body portion connected to the shoulder portion, 3. The laminated tube container according to claim 1, which is an injection molded tube container in which the head and body are integrally molded.

4. 4. The laminated tubular container according to claim 3, wherein the thickness of the body of the tubular container body is 1.0 mm or less.

5. 5. The laminated tubular container according to claim 1, wherein the oxygen barrier layer has a thickness of 7 to 12 μm.

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