Container

Abstract

To provide a container which has excellent recyclability and, upon producing a recycled container using a recycled resin after recycling, can obtain the recycled container of high quality.SOLUTION: A container comprises: a base material layer 55; a protective layer 57 provided on at least a part of a surface of the base material layer; and a barrier layer 56 provided between the base material layer and the protective layer. The base material layer includes a thermoplastic resin, the protective layer includes copolymerized polyester, upon measuring infrared absorption spectra by an infrared total reflection measurement method of a surface of the protective layer from the outside of the container, when an absorption degree at 1,340 cm is defined as A1340 and an absorption degree at 1,720 cm is defined as A1720, satisfying a relational expression 1: A1340 / A1720<0.15, and the barrier layer includes a water-soluble or alkali-soluble resin. The container is a vial bottle 50 including a mouth part 51, a neck part 52, a body part 53 and a bottom part 54, or the container is a syringe including a cylinder tip, an outer barrel, a gasket, a plunger and a flange.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a container.

Background Art

[0002] In recent years, for the purpose of reducing environmental burdens such as carbon dioxide emissions reduction, recycling of used plastic containers has been carried out. Since recycling needs to be performed with the same kind of material, for example, when recycling a used bottle, the collected bottle needs to be separated into a label, a cap, and a bottle body. Further, when the bottle body has a multilayer structure, for example, when including a base material layer and a coating layer provided on the surface of the base material layer, it is necessary to separate the base material layer and the coating layer.

[0003] Patent Document 1 discloses a plastic bottle having a polyvinyl alcohol coating as a barrier layer on the outer surface of a bottle body, and having a polyvinyl butyral coating as a protective layer on the polyvinyl alcohol coating. Since polyvinyl alcohol has water solubility, the plastic bottle disclosed in Patent Document 1 can dissolve the barrier layer between the support and the protective layer during recycling, and as a result, the base material layer, the barrier layer, and the protective layer can be separated.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When recycling a container as proposed in Patent Document 1, the base layer and the protective layer can be separated by crushing the container and performing water washing or the like, but they cannot be completely separated. A very small part (about several percent) is recycled with the protective layer still attached to the base layer. In that case, it is recycled as a recycled resin in which the resin (polyvinyl butyral) constituting the protective layer is added to the resin (polyester) of the base layer. Therefore, when manufacturing a container again using the recycled resin, quality deterioration such as yellowing may occur.

[0006] Therefore, an object of the present disclosure is to provide a container that is excellent in recyclability and can obtain a high-quality recycled container when manufacturing a recycled container using the recycled resin after recycling.

Means for Solving the Problems

[0007] The present disclosure is solved by the following embodiments. <1> In a container including a base layer, a protective layer provided on at least a part of the surface of the base layer, and a barrier layer provided between the base layer and the protective layer, the base layer contains a thermoplastic resin, when measuring the infrared absorption spectrum of the protective layer surface from the outside of the container by the infrared total reflection measurement method, the absorbance at 1340 cm -1 is A 1340 , and the absorbance at 1720 cm -1 is A 1720 , the following relational expression (1): A 1340 / A 1720 <0.15 (1) is satisfied and contains a copolymerized polyester, the barrier layer contains a water-soluble or alkali-soluble resin, the container is a vial having a mouth part, a neck part, a body part, and a bottom part. <2> The container according to <1>, wherein the protective layer and the barrier layer are provided at least on the neck part, the body part, and the bottom part. <3> In a container comprising a base material layer, a protective layer provided on at least a part of the surface of the base material layer, and a barrier layer provided between the base material layer and the protective layer, the base material layer contains a thermoplastic resin, when measuring the infrared absorption spectrum of the surface of the protective layer from the outside of the container by the infrared total reflection measurement method, the absorbance at 1340 cm -1 is A 1340 , and the absorbance at 1720 cm -1 is A 1720 , the following relational expression (1): A 1340 / A 1720 <0.15 (1) is satisfied and contains a copolyester, the barrier layer contains a water-soluble or alkali-soluble resin, the container is a syringe comprising a barrel tip, an outer barrel, a gasket, a plunger, and a flange. <4> The container according to <3>, wherein the protective layer and the barrier layer are provided at least on the outer barrel. <5> The container according to any one of <1> to <4>, wherein the thickness of the protective layer is 0.01 μm or more and 200.00 μm or less. <6> The container according to any one of <1> to <5>, wherein the protective layer contains a copolyester having a bimodal peak in the absorption peak range of 1225 cm -1 ~1255 cm -1 when measuring the infrared absorption spectrum of the surface of the protective layer from the outside of the container by the infrared total reflection measurement method. <7> The container according to any one of <1> to <6>, wherein the barrier layer contains a polyvinyl alcohol-based resin. <8> The container according to <7>, wherein the barrier layer further contains a carboxyl group-containing resin.

Advantages of the Invention

[0008] According to the present disclosure, by including a specific copolymer polyester in the protective layer, it is possible to obtain a container that is excellent in recyclability and can obtain a high-quality recycled container when manufacturing a recycled container using the recycled resin after recycling.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0010] <Container> The container of the present disclosure includes a base material layer, a protective layer provided on at least a part of the surface of the base material layer, and a barrier layer provided between the base material layer and the protective layer. In this specification, the “container” means a molded body for containing an article. Examples of the container include molded bodies such as compression molded bodies, injection molded bodies, blow molded bodies, and thermoformed bodies. Specific examples of the container include bottles, vials, cups, syringes such as prefilled syringes, trays, and packs. A vial is a container in which a rubber stopper is pushed into the mouth for sealing, and is mainly used as a container for medical reagents. A prefilled syringe is a syringe configured to store a chemical solution in a sealed state in a syringe container in advance, and to remove a sealing cap and connect it to an instrument such as an injection needle or a vascular catheter at the time of use so that the chemical solution can be administered to a patient.

[0011] Hereinafter, each component that the container of the present disclosure may include will be described.

[0012] (Base Material Layer) In the container of the present disclosure, the base material layer can maintain the form of the container and contains a thermoplastic resin. Examples of the thermoplastic resin contained in the base material layer include polyolefins such as polyethylene and polypropylene, cyclic polyolefins such as polymers obtained by polymerizing and hydrogenating ring-opening polymerizable cycloolefin-based monomers (such as norbornenes or cyclotetradecenes), cyclic olefin copolymers such as copolymers made from ring-opening polymerizable cycloolefin-based monomers and olefins (such as ethylene or α-olefins), polycarbonate, polyvinyl chloride, polyesters such as polyethylene terephthalate, polyamides such as nylon 6 and nylon 6,6, and mixtures thereof. Among these, from the viewpoint of moldability, polyester or polyolefin is preferred. Further, when the container is a vial, the thermoplastic resin constituting the base material layer is preferably a cyclic polyolefin. Also, when the container is a syringe, the thermoplastic resin constituting the base material layer is preferably a polyolefin, a cyclic polyolefin, or a cyclic olefin copolymer.

[0013] In this specification, "polyester" means a polymer polymerized by an ester bond. Such a polyester is usually obtained by polycondensing a dicarboxylic acid compound and a diol compound. Examples of the dicarboxylic acid compound include malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, dodecanedioic acid, eicosanedioic acid, pimelic acid, azelaic acid, methylmalonic acid, ethylmalonic acid, adamantanedicarboxylic acid, norbornenedicarboxylic acid, cyclohexanedicarboxylic acid, decahydro-naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 5-sodium sulfoisophthalic acid, phenyleneendodicarboxylic acid, anthracenedicarboxylic acid, phenanthrenedicarboxylic acid, 9,9'-bis(4-carboxyphenyl)fluorene acid, and ester derivatives thereof. Examples of the diol compound include ethylene glycol, 1,2-propanediol, 1,3-propanediol, butanediol, 2-methyl-1,3-propanediol, hexanediol, neopentyl glycol, cyclohexanedimethanol, cyclohexanediethanol, decahydronaphthalenedimethanol, decahydronaphthalenediethanol, norbornanedimethanol, norbornanedietanol, tricyclodecanedimethanol, tricyclodecaneethanol, tetracyclododecanedimethanol, tetracyclododecanediethanol, decahydronaphthalenedimethanol, decahydronaphthalenediethanol, 5-methylol-5-ethyl-2-(1,1-dimethyl-2-hydroxyethyl)-1,3-dioxane, cyclohexanediol, bicyclohexyl-4,4'-diol, 2,2-bis(4-hydroxycyclohexyl)propane, 2,2-bis(4-(2-hydroxyethoxy)cyclohexyl)propane, cyclopentanediol, 3-methyl-1,2-cyclopentanediol, 4-cyclopentene-1,3-diol, adamantadiol, paraxylene glycol, bisphenol A, bisphenol S, styrene glycol, trimethylolpropane, pentaerythritol, and bis-β-hydroxyethyl terephthalate (BHET).

[0014] The polyester is preferably polyethylene terephthalate or a modified polyethylene terephthalate obtained by polymerizing raw material monomers of polyethylene terephthalate and copolymer monomers. The copolymer monomers can be appropriately selected from the above-mentioned dicarboxylic acid components and diol components.

[0015] Within a range that does not impair the characteristics of the present disclosure, the polyester may contain monomers other than the dicarboxylic acid compound and the diol compound, but the content thereof is preferably 10 mol% or less, more preferably 5 mol% or less, and still more preferably 3 mol% or less based on all the constitutional units.

[0016] The polyester may be polymerized using a polymerization catalyst. Examples of the polymerization catalyst include a manganese (Mn) catalyst, a titanium (Ti) catalyst, an aluminum (Al) catalyst, a lithium (Li) catalyst, a germanium (Ge) catalyst, and an antimony (Sb) catalyst.

[0017] The above-mentioned polyester may be not only virgin polyester but also recycled polyester from the viewpoint of reducing environmental impact. In this specification, "virgin polyester" means polyester that has not been recycled, and "recycled polyester" means polyester recycled by collecting used products such as containers shipped to the market. In addition, as recycled polyester, there are polyester obtained by decomposing the collected used polyester containers to the monomer level and then repolymerizing them (hereinafter referred to as "chemical recycled polyester"), and polyester obtained by sorting, pulverizing, and washing the collected used products to remove contaminants and foreign substances to obtain flakes, and then treating the flakes under high temperature and reduced pressure for a certain period of time to remove the contaminants inside the resin (hereinafter referred to as "mechanical recycled polyester"). The mechanical recycled polyester may contain two or more kinds of catalysts. In this case, the mechanical recycled polyester may contain two or more of, for example, Sb catalyst polyester, Mn catalyst polyester, Ti catalyst polyester, Al catalyst polyester, Li catalyst polyester, and Ge catalyst polyester.

[0018] In mechanical recycled polyester, it is known that the content ratios of antimony (Sb) element, sodium (Na) element, calcium (Ca) element, and / or magnesium (Mg) element are different from those of virgin polyester and chemical recycled polyester. Specifically, it is known that mechanical recycled polyester contains Sb element at a ratio of 20 mg / L or more and 54 mg / L or less, Na element at a ratio of 12 mg / L or more, Ca element at a ratio of 4 mg / L or more, and / or Mg element at a ratio of 2.5 mg / L or more. Therefore, mechanical recycled polyester can be distinguished from virgin polyester and chemical recycled polyester by whether the polyester satisfies one or more of these content ratios. In addition, in mechanical recycled polyester, the content ratio of Sb element is preferably 25 mg / L or more and 50 mg / L or less, the content ratio of Na element is preferably 14 mg / L or more, the content ratio of Ca element is preferably 4.5 mg / L or more, and the content ratio of Mg element is preferably 3 mg / L or more.

[0019] When the container of the present disclosure contains mechanically recycled polyester, the content of the mechanically recycled polyester is preferably 20 parts by mass or more and 100 parts by mass or less, more preferably 60 parts by mass or more and 90 parts by mass or less, based on 100 parts by mass of the total amount of the resin material contained in the container.

[0020] From the viewpoint of recyclability, the content of one type of thermoplastic resin in the base material layer is preferably 85% by mass or more, more preferably 97% by mass or more.

[0021] The base material layer may contain additives within a range that does not impair the characteristics of the present disclosure. Examples of the additives include an oxygen absorber, a plasticizer, an ultraviolet stabilizer, an antioxidant, a matting agent, a deodorant, a flame retardant, a weathering agent, an antistatic agent, a friction reducer, a slip agent, a mold release agent, an antioxidant, and an ion exchanger. These additives can be used alone or in combination of two or more.

[0022] The base material layer may have a single-layer structure or a multilayer structure of two or more layers. When the base material layer has a multilayer structure, each layer may have the same composition or different compositions within a range that does not impair the characteristics of the present disclosure.

[0023] The base material layer is preferably subjected to a surface treatment. Examples of the surface treatment include a corona treatment, a low-temperature plasma treatment, a flame treatment, and a coating treatment. By performing such a surface treatment, the wettability of the surface of the base material layer can be improved, and the adhesion between the base material layer and the layer in contact with the base material layer can be improved.

[0024] The thickness of the base material layer is preferably 0.1 mm or more and 5.0 mm or less, more preferably 0.5 mm or more and 3.0 mm or less, still more preferably 0.5 mm or more and 2.0 mm or less, and even more preferably 1.0 mm or more and 1.5 mm or less. Incidentally, the thickness of the base material layer can be measured in the body portion or the outer cylinder of the container, and means the thickness of the cross-section at the location where the thickness of the cross-section of the base material layer is the smallest. Further, when the base material layer is multilayered, the thickness of the base material layer is the sum of the thicknesses of all the layers.

[0025] (Barrier layer) The barrier layer is a layer having gas barrier properties. A container provided with such a barrier layer can suppress the permeation of gases such as oxygen, and thus can suppress the deterioration of the contents.

[0026] In the container according to the present disclosure, the barrier layer has water solubility or alkali solubility. Thereby, a container excellent in recyclability can be obtained. The reason is as follows.

[0027] In the recycling of a used container, first, the container is crushed into flakes, and then washed using a liquid such as water and an alkali solution. When a barrier layer having water solubility or alkali solubility exists between the base material layer and the protective layer, in this washing step, the barrier layer dissolves, and the protective layer can be peeled off from the base material layer to separate the base material layer. Therefore, such a container is excellent in recyclability. Incidentally, the barrier layer may be a layer having both water solubility and alkali solubility.

[0028] In this specification, "water solubility" means that the barrier layer dissolves in distilled water at 20°C at 3% by mass or more, preferably 10% by mass or more, more preferably 20% by mass or more. Further, "alkali solubility" means that the barrier layer dissolves in a 1.5% by mass aqueous sodium hydroxide solution at 90°C at 3% by mass or more, preferably 10% by mass or more, more preferably 20% by mass or more.

[0029] In one embodiment, the barrier layer contains a polyvinyl alcohol-based resin. The polyvinyl alcohol-based resin is a water-soluble or alkali-soluble resin, and has a high cohesive force, so it has a high effect of blocking oxygen and water vapor. By including a polyvinyl alcohol-based resin in the barrier layer, a water-soluble or alkali-soluble barrier layer can be formed, and the gas barrier property of the container can be improved.

[0030] In one embodiment, the barrier layer contains a carboxyl group-containing resin and a polyvinyl alcohol-based resin. As described above, by including a polyvinyl alcohol-based resin in the barrier layer, a water-soluble or alkali-soluble barrier layer can be formed, and the gas barrier property of the container can be improved.

[0031] In addition, by including a carboxyl group-containing resin in the barrier layer, the water solubility or alkali solubility of the barrier layer is improved, and the recyclability of the container can be improved. Further, the carboxyl group of the carboxyl group-containing resin forms a hydrogen bond with the "-OH" of the polyvinyl alcohol-based resin or the solvent of the coating liquid used for forming the barrier layer (for example, water and an organic solvent having a hydroxy group, etc.), increasing the viscosity of the coating liquid. As a result, depending on the coating method, the thickness of the barrier layer can be increased with fewer coating times, improving the productivity of the container.

[0032] Hereinafter, the polyvinyl alcohol-based resin and the carboxyl group-containing resin will be described.

[0033] The polyvinyl alcohol-based resin (also referred to as "PVA-based resin") is a resin containing alcoholic hydroxy groups in the polymer structure. The PVA-based resin is usually obtained by saponifying a vinyl ester-based polymer.

[0034] Vinyl ester polymers are usually obtained by polymerizing vinyl ester monomers as polymerization components. Examples of vinyl ester monomers include fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caprylate, vinyl versatate, and vinyl monochloroacetate, and aromatic carboxylic acid vinyl esters such as vinyl benzoate (e.g., C7-12 arene carboxylic acid - vinyl ester). These monomers can be used alone or in combination of two or more.

[0035] Vinyl ester polymers may have units derived from other polymerizable monomers (monomers copolymerizable with vinyl esters). Examples of other polymerizable monomers include ethylene; α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene; alkyl methacrylates such as methyl methacrylate and ethyl methacrylate; chlorine-containing vinyl monomers such as vinyl chloride and vinylidene chloride; fluorine-containing vinyl monomers such as vinyl fluoride and vinylidene fluoride; unsaturated nitriles such as acrylonitrile and methacrylonitrile; aromatic vinyl monomers such as styrene and α-methylstyrene; and alkyl itaconates. These monomers can be used alone or in combination of two or more.

[0036] The PVA-based resin may be one in which a part of the vinyl alcohol units is modified by reactions such as acetalization, etherification, acetoacetylation, and cationization.

[0037] The degree of polymerization of the PVA-based resin is preferably 1000 or more and 4000 or less, more preferably 1500 or more and 3500 or less, and still more preferably 2000 or more and 3000 or less. The average degree of polymerization of the PVA resin can be measured in accordance with JIS K 6726:1994.

[0038] The saponification degree of the PVA-based resin is preferably 70.0 mol% or more and 99.9 mol% or less, more preferably 90.0 mol% or more and 99.5 mol% or less, and still more preferably 95.0 mol% or more and 99.5 mol% or less, from the viewpoints of excellent solubility in solvents and storage stability of the composition. The saponification degree of the PVA-based resin can be measured in accordance with JIS K 6726:1994.

[0039] The PVA-based resin can be used alone or in combination of two or more.

[0040] As the carboxy group-containing resin, existing carboxy group-containing resins can be used. The existing carboxy group-containing resins are a general term for resins containing a carboxy group in the polymer structure. The carboxy group-containing resins include homopolymers of carboxy group-containing unsaturated monomers, copolymers of carboxy group-containing unsaturated monomers, copolymers of carboxy group-containing unsaturated monomers and other polymerizable monomers, and polysaccharides containing a carboxy group in the molecule (also referred to as "acidic polysaccharides"). These carboxy group-containing resins can be used alone or in combination of two or more.

[0041] Note that the carboxy group includes not only free carboxy groups but also acid anhydride groups (specifically, dicarboxylic acid anhydride groups). The acid anhydride group may be partially ring-opened to form a carboxy group. In the carboxy group-containing resin, a part of the carboxy group may be neutralized with an alkali.

[0042] The carboxy group-containing unsaturated monomer is preferably an α,β-monoethylenically unsaturated carboxylic acid. Therefore, the carboxy group-containing resin includes homopolymers of α,β-monoethylenically unsaturated carboxylic acids, copolymers of two or more α,β-monoethylenically unsaturated carboxylic acids, and copolymers of α,β-monoethylenically unsaturated carboxylic acids and other polymerizable monomers. Examples of other polymerizable monomers include ethylenically unsaturated monomers.

[0043] Examples of the α,β-monoethylenically unsaturated carboxylic acid include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; and unsaturated dicarboxylic acid anhydrides such as maleic anhydride and itaconic anhydride. These acids can be used alone or in combination of two or more.

[0044] The α,β-monoethylenically unsaturated carboxylic acid is preferably selected from one or more of acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, and more preferably selected from one or more of acrylic acid, methacrylic acid, and maleic acid.

[0045] Examples of other polymerizable monomers copolymerizable with the α,β-monoethylenically unsaturated carboxylic acid, particularly ethylenically unsaturated monomers, include ethylene; α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene; vinyl esters of saturated carboxylic acids such as vinyl acetate; alkyl acrylates such as methyl acrylate and ethyl acrylate; alkyl methacrylates such as methyl methacrylate and ethyl methacrylate; chlorine-containing vinyl monomers such as vinyl chloride and vinylidene chloride; fluorine-containing vinyl monomers such as vinyl fluoride and vinylidene fluoride; unsaturated nitriles such as acrylonitrile and methacrylonitrile; aromatic vinyl monomers such as styrene and α-methylstyrene; and alkyl itaconates. These monomers can be used alone or in combination of two or more.

[0046] Examples of the carboxy group-containing polysaccharides include acidic polysaccharides having a carboxy group in the molecule, such as alginic acid, carboxymethyl cellulose, and pectin. These acidic polysaccharides can be used alone or in combination of two or more. The acidic polysaccharides can be used in combination with a (co)polymer of an α,β-monoethylenically unsaturated carboxylic acid.

[0047] In the container of the present disclosure, when the carboxy group-containing resin is a copolymer of an α,β-monoethylenically unsaturated carboxylic acid and other ethylenically unsaturated monomers, the composition of the copolymer is such that the composition of the α,β-monoethylenically unsaturated carboxylic acid monomer is preferably 60 mol% or more, more preferably 80 mol% or more, and still more preferably 90 mol% or more.

[0048] The carboxy group-containing resin is preferably a homopolymer or copolymer obtained by polymerization of only an α,β-monoethylenically unsaturated carboxylic acid. When the polycarboxylic acid-based polymer is a (co)polymer composed of only an α,β-monoethylenically unsaturated carboxylic acid, the carboxy group-containing resin is preferably a homopolymer, copolymer, or a mixture of two or more thereof obtained from a carboxylic acid selected from one or more of acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, and more preferably a homopolymer, copolymer, or a mixture of two or more thereof obtained from a carboxylic acid selected from one or more of acrylic acid, methacrylic acid, and maleic acid.

[0049] The carboxy group-containing resin is preferably selected from one or more of polyacrylic acid, polymethacrylic acid, and maleic acid polymers. The carboxy group-containing resin is relatively easy to obtain and is preferably polyacrylic acid from the viewpoints of recyclability and gas barrier properties.

[0050] The number average molecular weight of the carboxy group-containing resin is preferably in the range of 2,000 or more and 10,000,000 or less, more preferably in the range of 5,000 or more and 1,000,000 or less, and still more preferably in the range of 10,000 or more and 500,000 or less. The number average molecular weight means a value calculated by gel permeation chromatography according to a conventional method.

[0051] In the barrier layer, the content of the polyvinyl alcohol-based resin is preferably 20% by mass or more and 99% by mass or less, more preferably 30% by mass or more and 98% by mass or less, and still more preferably 40% by mass or more and 95% by mass or less, based on all components contained in the barrier layer.

[0052] By setting the content of the polyvinyl alcohol-based resin to 20% by mass or more, the gas barrier property of the container can be further improved. By setting the content of the polyvinyl alcohol-based resin to 99% by mass or less, the recyclability of the container can be further improved.

[0053] When the barrier layer contains a carboxyl group-containing resin and a polyvinyl alcohol-based resin, the content of the carboxyl group-containing resin is preferably 1% by mass or more and 80% by mass or less, more preferably 2% by mass or more and 70% by mass or less, and still more preferably 5% by mass or more and 60% by mass or less, based on all components contained in the barrier layer.

[0054] By setting the content of the carboxyl group-containing resin to 1% by mass or more, the recyclability of the container can be further improved. By setting the content of the carboxyl group-containing resin to 80% by mass or less, the gas barrier property of the container can be further improved.

[0055] When the barrier layer contains a carboxyl group-containing resin and a polyvinyl alcohol-based resin, the mass ratio of the carboxyl group-containing resin to the polyvinyl alcohol-based resin (carboxyl group-containing resin / polyvinyl alcohol-based resin) is preferably 1 / 20 or more and 10 / 1 or less, more preferably 1 / 15 or more and 5 / 1 or less, and still more preferably 1 / 10 or more and 2 / 1 or less.

[0056] By setting the above mass ratio to 1 / 20 or more, the recyclability of the container can be further improved. By setting the above mass ratio to 10 / 1 or less, the gas barrier property of the container can be further improved. Note that the above mass ratio is a solid content ratio.

[0057] The barrier layer may contain additives as long as the properties of the present disclosure are not impaired. Examples of the additives include an oxygen absorber, a plasticizer, an ultraviolet stabilizer, an antioxidant, a matting agent, a deodorant, a flame retardant, a weathering agent, an antistatic agent, a yarn friction reducer, a slip agent, a mold release agent, an antioxidant, and an ion exchanger. These additives can be used alone or in combination of two or more kinds.

[0058] The barrier layer may be a single layer or a multilayer of two or more layers. Further, when the barrier layer is a multilayer, each layer may have the same composition or different compositions.

[0059] The thickness of the barrier layer is preferably 0.1 μm or more and 200.0 μm or less, more preferably 0.5 μm or more and 100.0 μm or less, still more preferably 0.7 μm or more and 50.0 μm or less, and even more preferably 5.0 μm or more and 30.0 μm or less. Note that the thickness of the barrier layer can be measured at the body portion or the outer cylinder of the container, and means the thickness of the cross-section at the location where the thickness of the cross-section of the barrier layer is the smallest. Further, when the barrier layer is a multilayer, the thickness of the barrier layer is the sum of the thicknesses of all the layers.

[0060] The barrier layer may be colored in colors such as red, blue, yellow, green, brown, dark brown, orange, black, and white, and may be further transparent or opaque. When the barrier layer is colored, light entering the container from the outside such as sunlight can be absorbed in the same manner as when coloring the barrier layer, and deterioration of the content of the container can be suppressed. Since visible light with a wavelength of 400 nm or more and 500 nm or less can be effectively absorbed, the barrier layer is preferably colored in brown or orange. For coloring the barrier layer, for example, a coloring agent can be used.

[0061] (Protective layer) The protective layer is for protecting the barrier layer. By providing the container with the protective layer, during the manufacturing and use of the container, deterioration of the barrier function can be suppressed due to physical factors such as breakage or peeling of the barrier layer, or chemical factors such as moisture absorption or dissolution. In the container of the present disclosure, the protective layer is provided detachably from the base material layer. That is, as described above, when the container is recycled, the barrier layer dissolves and the protective layer can be peeled off from the base material layer, and as a result, the base material layer and the protective layer can be easily separated.

[0062] In the container according to an embodiment of the present disclosure, the protective layer contains a copolyester. In the present disclosure, the copolyester is obtained by polycondensing terephthalic acid as the main dicarboxylic acid component and ethylene glycol as the main diol component, and contains monomers other than terephthalic acid and ethylene glycol as copolymerization components. In the present disclosure, as such a copolyester, when measuring the infrared absorption spectrum by the infrared total reflection measurement method (ATR method) of the surface of the protective layer from the outside of the container, at 1340 cm -1 the absorbance is A 1340 and at 1720 cm -1 the absorbance is A 1720 when the following relational expression (1): A 1340 / A 1720 <0.15 (1) is satisfied, a copolyester is used. The absorption at 1340 cm -1 is the absorption due to the angular vibration of CH 2 (trans structure) of ethylene glycol, and the absorption at 1720 cm -1 is due to the sum of the absorption derived from the carbonyl group and the absorption based on the ester structure. That is, a copolyester in which the absorption due to the angular vibration of CH 2 (trans structure) (absorption at 1340 cm -1 ) is less than a predetermined ratio with respect to the absorption derived from the carbonyl or ester structure is used for the protective layer. In the present disclosure, by using the copolymerized polyester satisfying the above formula (1) as a constituent material of the protective layer, the recyclability of the container can be further improved. Further, by using the specific copolymerized polyester described above as the protective layer, when the container of the present disclosure is recycled, even if the protective layer is contained in the base material layer at a few percent level, the discoloration of the obtained recycled resin is small, and the quality of the container (recycled product) using the recycled resin can be ensured.

[0063] In the present disclosure, the infrared absorption spectrum by the ATR method was measured under the following measurement conditions using a Fourier transform infrared spectrometer (Nicolet 6700 manufactured by Thermo Scientific) with a Ge prism pressed against a test piece obtained by cutting out the container into a size of 5 mm × 5 mm. (Measurement conditions) Incident angle: 45 degrees Resolution: 4 cm -1 Measurement wave number range: 700 to 4000 cm -1 Number of integrations: 64 times

[0064] As a preferable copolymerized polyester constituting the protective layer, when the infrared absorption spectrum by the infrared total reflection measurement method of the protective layer surface is measured from the outside of the container while satisfying the above formula (1), 1225 cm -1 ~1255 cm -1It is preferable that the copolymerized polyester having an absorption peak within the range has a bimodal peak. Such a copolymerized polyester contains a diol component other than ethylene glycol. For example, aliphatic diols such as neopentyl glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,9-nonanediol, 1,10-decanediol; alicyclic diols such as 1,4-cyclohexanedimethanol, 1,4-cyclohexanedietanol; and diol components such as aliphatic polyhydric alcohols such as trimethylolpropane and pentaerythritol can be mentioned. Among these, neopentyl glycol and propylene glycol are preferable. The ratio of the component other than the ethylene glycol component in the diol component is not particularly limited as long as the above formula (1) is satisfied, but the ratio of ethylene glycol in the diol component is preferably 50 mol% or more.

[0065] In addition, the copolymerized polyester contains terephthalic acid as the main dicarboxylic acid component, but as the dicarboxylic acid copolymer component, aromatic dicarboxylic acids such as isophthalic acid, naphthalene-1,4- or -2,6-dicarboxylic acid, 5-sodium sulfoisophthalic acid, 4,4'-diphenyldicarboxylic acid, diphenylsulfodicarboxylic acid; and aliphatic dicarboxylic acids such as glutaric acid, adipic acid, sebacic acid, azelaic acid, oxalic acid, and succinic acid may be included. Among these, from the viewpoint of the effects of the present disclosure, isophthalic acid is preferable.

[0066] The copolyester constituting the protective layer preferably has a weight average molecular weight of more than 1,000 and 20,000 or less. When the weight average molecular weight of the copolyester (hereinafter sometimes referred to as Mw) is 1,000 or less, tack may occur in the protective layer, deteriorating the handleability of the container. Further, when Mw exceeds 20,000, transparency may decrease when the container is recycled to obtain recycled resin, and coloring problems may occur when the container is manufactured from the recycled resin. The preferred range of Mw of the copolyester is 10,000 or more and 18,000 or less. The weight average molecular weight means a value calculated by gel permeation chromatography according to a conventional method.

[0067] In one embodiment, the copolyester preferably has a glass transition temperature of 35°C or higher and 100°C or lower. By including the copolymer component as described above, the glass transition temperature (hereinafter sometimes referred to as Tg) is lower than that of polyethylene terephthalate, improving the film quality of the protective layer. On the other hand, if the glass transition temperature is too low, the heat resistance may be poor, or the handleability may deteriorate when peeling the protective layer from the base material layer during recycling. The preferred glass transition temperature is 65°C or higher and 90°C or lower. The glass transition temperature means a value calculated from the inflection point of the endothermic peak accompanying the glass transition using a differential scanning calorimeter according to a conventional method.

[0068] The protective layer may contain additives as long as the characteristics of the present disclosure are not impaired. Examples of the additives include an oxygen absorber, a plasticizer, an ultraviolet stabilizer, an antioxidant, an anti-coloring agent, a matting agent, a deodorant, a flame retardant, a weathering agent, an antistatic agent, a yarn friction reducer, a slip agent, a release agent, an antioxidant, an ion exchanger, and a coloring agent. These additives can be used alone or in combination of two or more.

[0069] The protective layer may be a single layer or a multilayer of two or more layers. Further, when the protective layer is a multilayer, each layer may have the same composition or different compositions.

[0070] The protective layer may be colored in colors such as red, blue, yellow, green, brown, dark brown, orange, black, and white, and may be further transparent or opaque. When the protective layer is colored, similar to the case of coloring the barrier layer, it can absorb light entering the container from the outside such as sunlight, and can suppress the deterioration of the contents of the container. Since it can effectively absorb visible light with a wavelength of 400 nm or more and 500 nm or less, the protective layer is preferably colored in brown or orange or the like. For coloring the protective layer, for example, a coloring agent can be used.

[0071] The thickness of the protective layer is preferably 0.01 μm or more and 200.00 μm or less, more preferably 0.10 μm or more and 70.00 μm or less, still more preferably 0.50 μm or more and 50.00 μm or less, and even more preferably 0.70 μm or more and 30.00 μm or less. Thereby, the deterioration resistance of the barrier layer can be further improved. In addition, the thickness of the protective layer can be measured on the body or outer cylinder of the container, and means the thickness of the cross-section at the location where the thickness of the cross-section of the protective layer is the smallest. Further, when the protective layer is multilayer, the thickness of the protective layer is the sum of the thicknesses of all the layers.

[0072] (Evaporation film) In order to further improve the gas barrier property of the container of the present disclosure, it may have an evaporation film.

[0073] Examples of the evaporation film include evaporation films composed of metals such as aluminum, inorganic oxides such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide, organosilicon compounds such as hexamethyldisiloxane, and hard carbon films such as DLC (Diamond Like Carbon) films. In addition, the hard carbon film made of a DLC film is also called an i-carbon film or a hydrogenated amorphous carbon film (a-C:H), and is an amorphous carbon film mainly composed of SP 3 bonding.

[0074] Further, the thickness of the vapor deposition film is not particularly limited, and can be, for example, 1 nm or more and 150 nm or less. The thickness of the vapor deposition film can be measured, for example, on the body portion or the outer cylinder of the container, and means the thickness of the cross section at the location where the thickness of the cross section of the vapor deposition film is the smallest.

[0075] The formation of the vapor deposition film can be carried out by a conventionally known method, and examples thereof include physical vapor deposition methods (Physical Vapor Deposition method, PVD method) such as vacuum evaporation method, sputtering method, and ion plating method, and chemical vapor deposition methods (Chemical Vapor Deposition method, CVD method) such as plasma chemical vapor deposition method, thermal chemical vapor deposition method, and photo chemical vapor deposition method.

[0076] Hereinafter, taking a vial and a syringe as examples, an embodiment of the structure of the container according to the present disclosure will be described with reference to the drawings. Each figure is shown schematically. Therefore, the size and shape of each part are exaggerated as appropriate for easy understanding. Further, it can be implemented with appropriate changes without departing from the technical idea. Also, the numerical values and material names of the dimensions of each member described in this specification are examples as an embodiment, and are not limited thereto, and can be appropriately selected and used. In this specification, terms specifying shapes and geometric conditions, such as terms like parallel, orthogonal, and perpendicular, shall be interpreted to include not only the strict meaning but also substantially the same state.

[0077] FIG. 1 is a schematic semi-cross-sectional view showing a vial which is an embodiment of the container of the present disclosure. As shown in FIG. 1, the vial 50 includes a cylindrical body portion 53 for accommodating articles such as medicines, a bottom portion 54 closing the lower end of the body portion 53, a cylindrical neck portion 52 provided above the body portion 53 and having an outer diameter smaller than that of the body portion 53, and a cylindrical mouth portion 51 provided above the neck portion 52 and having an outer diameter larger than that of the neck portion 52.

[0078] The body portion 53 in FIG. 1 has a cylindrical shape with a substantially uniform diameter as a whole, but is not limited thereto, and the body portion 53 may have a polygonal cylindrical shape such as a square cylindrical shape or an octagonal cylindrical shape. Alternatively, the body portion 53 may have a cylindrical shape with a non-uniform horizontal cross section from top to bottom. Also, the body portion 53 in FIG. 1 has no unevenness and has a substantially flat surface, but is not limited to this. For example, unevenness such as panels or grooves may be formed on the body portion 53.

[0079] As shown in FIG. 1, the vial 50 has a mouth portion 51 formed of a base material layer 55, and a neck portion 52, a body portion 53, and a bottom portion 54 are formed of the base material layer 55, a barrier layer 56, and a protective layer 57. As shown in FIG. 1, in the neck portion 52, the body portion 53, and the bottom portion 54, the barrier layer 56 and the protective layer 57 are provided over the entire outer region of the base material layer 55 so as to surround the base material layer 55. In one embodiment, the barrier layer 56 and the protective layer 57 may be provided in all or a partial region of one or more selected from the mouth portion 51, the neck portion 52, the body portion 53, and the bottom portion 54. The barrier layer 56 and the protective layer 57 are preferably provided at least in the neck portion 52, the body portion 53, and the bottom portion 54.

[0080] The barrier layer 56 and the protective layer 57 may be provided inside the vial 50 (not shown). The vial 50 may be provided with a vapor deposition film on at least one selected from the group including the inside and the outside of the vial (not shown).

[0081] When the vial 50 is used for storing chemicals or the like, after storing the chemicals or the like in the body portion 53 thereof, a rubber stopper having gas barrier properties (not shown) is fitted into the mouth portion 51. Further, a cap (not shown) made of a relatively soft metal such as aluminum is caulked (wound and tightened) thereon, whereby the vial 50 is sealed. Thereby, a vial 50 having gas barrier properties can be obtained.

[0082] Figure 2 is a schematic semi-cross-sectional view showing a syringe which is an embodiment of the container of the present disclosure. As shown in Figure 2, the syringe 60 includes a cylindrical outer cylinder 61 having a substantially uniform diameter as a whole, a cylinder tip 62 formed at the upper end of the outer cylinder 61 for injecting or discharging a chemical solution, a gasket 63 housed in the outer cylinder 61 and capable of sliding in the outer cylinder 61 in a liquid-tight manner, a plunger 64 attached to the gasket 63 for sliding the gasket 63 up and down in the outer cylinder 61, and a flange 65 for hanging a finger when pushing out and moving the plunger 64 upward.

[0083] As shown in Figure 2, in the syringe 60, the cylinder tip 62 and the flange 65 are composed of a base material layer 66, and the outer cylinder 61 is composed of a base material layer 66, a barrier layer 67, and a protective layer 68. As shown in Figure 2, in the outer cylinder 61, the barrier layer 67 and the protective layer 68 are provided over the entire outer area of the base material layer 66 so as to surround the base material layer 66. In one embodiment, the barrier layer 67 and the protective layer 68 may be provided in all or a partial area of one or more selected from the outer cylinder 61, the cylinder tip 62, and the flange 65. It is preferable that the barrier layer 67 and the protective layer 68 are provided at least on the outer cylinder 61.

[0084] The barrier layer 67 and the protective layer 68 may be provided inside one or more selected from the outer cylinder 61, the cylinder tip 62, and the flange 65 (not shown). The syringe 60 may be provided with a vapor deposition film on at least one selected from one or more selected from the outer cylinder 61, the cylinder tip 62, and the flange 65, including the inside and the outside (not shown).

[0085] The cylinder tip 62 is sealed with a sealing cap (not shown). Thereby, the syringe 60 having gas barrier properties can be obtained. The sealing cap may be a cap-shaped one made of an elastic material such as rubber or elastomer and covering the tube tip 62. Alternatively, a cap-shaped molded article may be made of a synthetic polymer resin composition, and a cap-shaped one with an elastic material such as rubber or elastomer disposed so as to close the tube tip 62 may be put over the tube tip 62 as the sealing cap. Or, a cap-shaped molded article with a through-hole provided on the top surface may be made of a synthetic polymer resin composition, and a cap-shaped sealing cap with a resealing material such as rubber or elastomer disposed so as to close the through-hole may be put over the tube tip 62. Note that as the synthetic polymer resin composition, a composition containing polypropylene or cyclic polyolefin as a constituent component is suitable.

[0086] In the container of the present disclosure, the oxygen permeability is preferably 4.54540 cc / day·m 2 ·0.21 atm or less, more preferably 1.81810 cc / day·m 2 ·0.21 atm or less, still more preferably 0.18200 cc / day·m 2 ·0.21 atm or less, and even more preferably 0.11400 cc / day·m 2 ·0.21 atm or less is even more preferable. Note that the above oxygen permeability is a value measured under the conditions of 23°C and a humidity of 40% RH using an oxygen permeability measuring device (for example, manufactured by MOCON, trade name: OX-TRAN 2 / 61) in accordance with JIS K 7126-2:2006. The measurement is made for the entire container with the opening portion blocked by a jig, and the value is obtained by dividing by the surface area of the entire container excluding the opening portion.

[0087] The thickness of the container of the present disclosure is preferably 0.1 mm or more and 5.0 mm or less, more preferably 0.1 mm or more and 3.0 mm or less, still more preferably 0.5 mm or more and 2.5 mm or less, and even more preferably 0.5 mm or more and 1.7 mm or less. Incidentally, the thickness of the container can be measured, for example, at least in the body or outer cylinder of the container having a base material layer, a barrier layer, and a protective layer. The thickness of the container means the thickness of the cross-section at the location where the thickness of the cross-section of the container is the smallest.

[0088] The container of the present disclosure preferably has a volume / mass of 5 mL / g or more and 50 mL / g or less, more preferably 8 mL / g or more and 45 mL / g or less. By setting the volume / mass of the container to a certain value or more, the weight reduction of the container can be achieved. Also, by setting the volume / mass of the container to a certain value or less, the strength of the container can be improved.

[0089] The container according to an embodiment of the present disclosure may have a volume of, for example, 2000 mL or less. The volume of the container is preferably 50 mL or less. Also, the volume of the container of the present disclosure is preferably 1 mL or more, more preferably 2 mL or more.

[0090] In the container according to one embodiment, the transmittance of visible light with a wavelength of 400 nm or more and 500 nm or less is preferably 20% or less. Thereby, the deterioration of the content can be suppressed. The transmittance is more preferably 15% or less, still more preferably 5% or less, and even more preferably 1% or less. Such a transmittance can be adjusted by appropriately coloring at least one layer selected from the group including the protective layer and the barrier layer. The transmittance of visible light with a wavelength of 400 nm or more and 500 nm or less can be obtained by measuring the light transmittance of the visible light wavelength at intervals of 0.5 nm using a spectrophotometer. As the spectrophotometer, an ultraviolet-visible spectrophotometer manufactured by Shimadzu Corporation can be used. Incidentally, the transmittance of the container is measured, for example, at least in the body or outer cylinder of the container having a base material layer, a barrier layer, and a protective layer.

[0091] The container according to an embodiment of the present disclosure may have printing on its surface. The image formed by the printing is not particularly limited, and examples thereof include patterns and characters. From the viewpoint of not being affected by the color tone of the container, the printing is preferably performed on the outer surface of the container. The printing can be performed by a known method. Examples of the printing method include an inkjet method, a gravure printing method, an offset printing method, a flexographic printing method, a thermal transfer method, a silk screen method, a pad method, a hot stamping method, a cold stamping method, and the like.

[0092] <Method for manufacturing a container> Hereinafter, a method for manufacturing a container according to an embodiment of the present disclosure will be described while exemplifying a vial.

[0093] In one embodiment, the vial 50 shown in FIG. 1 can be manufactured by the following procedure. First, a base material layer 55 having a mouth portion 51, a neck portion 52, a body portion 53, and a bottom portion 54 is produced by injection molding a material constituting the base material layer 55 using a conventionally known apparatus. Next, a coating liquid for the barrier layer containing a material constituting the barrier layer 56 and a solvent is prepared. Next, the coating liquid for the barrier layer is applied to the neck portion 52, the body portion 53, and the bottom portion 54 of the base material layer 55 to form a coating film. Next, the coating film is dried to remove the solvent, thereby forming the barrier layer 56. Next, a coating liquid for the protective layer containing a material constituting the protective layer 57 and a solvent is prepared. Next, the coating liquid for the protective layer is applied to the surface of the barrier layer 56 to form a coating film. Next, the coating film is dried to remove the solvent, thereby forming the protective layer 57, and the vial 50 shown in FIG. 1 can be manufactured. Note that the syringe 60 shown in FIG. 2 can be manufactured by appropriately selecting the shape of the base material layer 66 and the coating locations of the coating liquid for the barrier layer and the coating liquid for the protective layer.

[0094] The solvent used in the coating liquid for the barrier layer should be able to dissolve or emulsify and disperse the materials constituting the barrier layer. Examples of the solvent include water; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, and n-pentyl alcohol; and polar organic solvents such as dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used alone or in combination of two or more. Preferably, water, alcohols, or a mixture thereof is used as the solvent, and more preferably, a mixed solvent of water and isopropyl alcohol is used. This can improve the viscosity of the coating liquid for the barrier layer and reduce the number of coating times, thus improving the productivity of the container.

[0095] In the coating liquid for the barrier layer, the total solid content concentration of the materials constituting the barrier layer is preferably 2% by mass or more and 15% by mass or less, and more preferably 3% by mass or more and 10% by mass or less. This can form a barrier layer with uniform thickness.

[0096] The viscosity of the coating liquid for the barrier layer is preferably 25 mPa·s or more and 300 mPa·s or less, and more preferably 30 mPa·s or more and 270 mPa·s or less. This can further improve the productivity of the container. The viscosity of the coating liquid can be measured using a rotational viscometer at a temperature of 20°C in accordance with JIS Z 8803:2011.

[0097] The viscosity of the coating liquid for the barrier layer can be measured using a rotational viscometer at a temperature of 20°C in accordance with JIS Z 8803:2011.

[0098] The coating of the coating liquid for the barrier layer can be performed by a conventionally known method. Examples of the coating method include coating with a brush or the like, immersing the container in the coating liquid for the barrier layer, and spraying the coating liquid for the barrier layer onto the surface of the container.

[0099] The drying temperature of the coating film formed from the coating liquid for the barrier layer is a temperature at which the solvent can be removed. The drying temperature is preferably 20°C or higher and 80°C or lower, more preferably 40°C or higher and 70°C or lower, and still more preferably 50°C or higher and 70°C or lower.

[0100] The solvent used in the coating liquid for the protective layer is not particularly limited as long as it can dissolve and emulsify and disperse the material for forming the protective layer. For example, water, acetone, ethyl methyl ketone, methyl isobutyl ketone, methyl ethyl ketone, ethyl acetate, n-propyl acetate, methanol, ethanol, isopropanol, hexane, heptane, cyclohexane, methylcyclohexane, etc. can be used. Among these, since the polymer component can be well dissolved or emulsified and dispersed, the solvent used in the coating liquid for the protective layer is preferably ethyl acetate, methyl ethyl ketone, or a mixed solvent of ethyl acetate and methyl ethyl ketone.

[0101] The coating of the coating liquid for the protective layer can be performed by a conventionally known method. Examples of the coating method include a method of applying with a brush or the like, a method of immersing a container in the coating liquid for the protective layer, a method of spraying the coating liquid for the protective layer on the surface of the container, etc. The protective layer (coating layer) can be formed by applying these methods.

[0102] The drying temperature of the coating film formed from the coating liquid for the protective layer is a temperature at which the solvent can be removed. The drying temperature is preferably 40°C or higher and 80°C or lower, more preferably 50°C or higher and 70°C or lower.

[0103] The method for manufacturing a container according to one embodiment may include a step of printing an image such as a pattern and characters on the surface of the container. Printing can be performed by known methods. Examples of printing methods include, for example, inkjet method, gravure printing method, offset printing method, flexographic printing method, thermal transfer method, silk screen method, pad method, hot stamping method, cold stamping method, and the like. For example, when performing printing by the inkjet method, a UV-curable ink is applied to a container, and UV irradiation is performed thereon to cure it, thereby performing printing. Further, printing may be performed using a thermal transfer sheet.

Examples

[0104] Next, examples will be given to explain the present disclosure in more detail, but the present disclosure is not limited to these examples.

[0105] [Example 1] As a base material layer, a syringe body (product name: ClearJect (registered trademark), manufactured by Daisheng Chemical Co., Ltd.) made of cyclic polyolefin, having a cross-sectional thickness of the outer cylinder of 1.5 mm and a capacity of 2.5 mL was prepared. Next, 18.75 g of PVA (manufactured by Kuraray Co., Ltd., product name: 60-98, degree of polymerization: 2400, saponification degree: 98 to 99%) was added to a mixed solvent of 440.8 g of water and 21.7 g of isopropyl alcohol (IPA). Subsequently, 18.75 g of polyacrylic acid (manufactured by Nippon Shokubai Co., Ltd., product name: AS-58, number average molecular weight: 106,000) was added and stirred to prepare a coating liquid for a barrier layer having a solid content concentration of 7.5% by mass (viscosity: 195.5 mPa·s (20 °C)). This coating liquid for the barrier layer was applied to the outer cylinder of the above syringe body with a cap attached to the tip of the cylinder to form a coating film. The coating film was dried at 50 °C for 10 minutes to form a barrier layer having a thickness of 12 μm. The mass ratio (solid content ratio) of polyacrylic acid to PVA is 1 / 1. Next, a copolymer polyester A (a copolymer polyester containing ethylene glycol and neopentyl glycol as diol copolymer components and terephthalic acid and isophthalic acid as dicarboxylic acid copolymer components, Tg = 67°C, Mw = 17,000) was dissolved in a mixed solvent of ethyl acetate and methyl ethyl ketone (a 1:1 mixed solution) to prepare a coating liquid for the protective layer. This coating liquid for the protective layer was applied to the outer cylinder with a cap attached to the tip of the cylinder of the syringe body to form a coating film. By drying the coating film at 50°C for 10 minutes, a protective layer with a thickness of 30 μm was formed, and the syringe of Example 1 was produced. The syringe of Example 1 had a structure as shown in Figure 2, except that it did not have a gasket and a plunger.

[0106] [Example 2] In the coating liquid for the protective layer used in Example 1, except that a coating liquid for the protective layer in which a copolymer polyester B (a copolymer polyester containing ethylene glycol and propylene glycol as diol copolymer components and containing terephthalic acid as a dicarboxylic acid copolymer component, Tg = 85°C, Mw = 13,000) was dissolved in ethyl acetate was used instead of the copolymer polyester A, a syringe of Example 2 was produced in the same manner as in Example 1.

[0107] [Example 3] In the coating liquid for the protective layer used in Example 1, except that a coating liquid for the protective layer in which a copolymer polyester C (a copolymer polyester containing ethylene glycol and neopentyl glycol as diol copolymer components and containing terephthalic acid and isophthalic acid as dicarboxylic acid copolymer components, and partially ethylene oxide-modified, Tg = 60°C, Mw = 20,000) was dissolved in ethyl acetate was used instead of the copolymer polyester A, a syringe of Example 3 was produced in the same manner as in Example 1.

[0108] [Comparative Example 1] Instead of the coating liquid for the protective layer used in Example 1, a coating liquid for the protective layer in which Mowital B30H (polyvinyl butyral, average degree of polymerization 400 to 650, Mw = 28,000 to 38,000, Tg = 68 ° C, manufactured by Kuraray Co., Ltd.) was dissolved in ethyl acetate was used, and a syringe of Comparative Example 1 was produced in the same manner as in Example 1.

[0109] <ATR-IR Measurement> From the outer cylinder of each syringe obtained as described above, a 5 × 5 mm test piece was cut out, a Ge prism was pressed against the test piece, and an infrared absorption spectrum was measured under the following measurement conditions using a Fourier transform infrared spectrometer (Nicolet 6700 manufactured by Thermo Scientific). In the ATR-IR measurement, the infrared absorption spectrum of the front side of the test piece (the surface of the protective layer on the outside of the syringe) was measured. (Measurement Conditions) Incident Angle: 45 degrees Resolution: 4 cm -1 Measurement Wavenumber Range: 700 to 4000 cm -1 Number of Integrations: 64 times

[0110] The infrared absorption spectra of the surface of the protective layer in the syringe of Example 1 are shown in Fig. 3. The infrared absorption spectrum is an enlarged view of the range of 700 to 2000 cm. In the infrared absorption spectrum of the surface of the protective layer in Fig. 3, it can be seen that the absorption peak in the range of 1225 cm to 1255 cm is bimodal. -1 Also, the value of A / A calculated from the infrared absorption spectrum is shown in Table 1 below. For the syringes of Example 2 and 3 and Comparative Example 1, the values of A / A calculated from the infrared absorption spectra of the surface of the protective layer are also shown in Table 1 below. -1 ~1255cm -1 It can be seen that the absorption peak in the range is bimodal. Also, the value of A 1340 / A 1720 calculated from the infrared absorption spectrum is shown in Table 1 below. For the syringes of Example 2 and 3 and Comparative Example 1, the values of A 1340 / A 1720 calculated from the infrared absorption spectra of the surface of the protective layer are also shown in Table 1 below.

[0111] <Recyclability Evaluation> Each syringe obtained in the above Examples and Comparative Examples was crushed into flakes, and the flakes were then placed in a 1.5% by mass aqueous solution of sodium hydroxide at 90°C and stirred for 15 minutes. The flakes were then recovered from the cleaning solution, and it was visually confirmed whether the base layer and the protective layer were separated. The evaluation criteria for recyclability were as follows: ○: The protective layer is almost completely peeled off from the base layer. ×: A part of the protective layer is peeled off from the base layer. The evaluation results are shown in Table 1.

[0112] <Evaluation of recycled containers> The same pellet-shaped resin as the cyclic polyolefin used in Example 1 was melted and used in an injection molding machine to produce a plate with a thickness of 1.5 mm. The L 2 value defined in JIS Z 8729:2004 was measured for the produced plate using a color difference meter (Murakami Color Research Laboratory Co., Ltd.). * a * b * L in color space * a * b * (Each measured value was expressed as L 0 * a 0 * b 0 * (It was decided that.)

[0113] In addition, a mixed resin was prepared by adding each copolymer polyester to 100 parts by mass of the same pellet-shaped resin as the cyclic polyolefin used in Example 1 in a ratio of 0.105 parts by mass, and the mixed resin was melted and made into a plate having a thickness of 1.5 mm using an injection molding machine. * a * b * (Each measured value was expressed as L 1 * a 1 * b 1 * From the measured values, b 1 * and b 0 *The absolute value of the difference Δb * (Δb * = |b 1 * - b 0 * |) was calculated. The results are shown in Table 1.

[0114]

Table 1

Explanation of Symbols

[0115] 50: Vial 51: Mouth 52: Neck 53: Body 54: Bottom 55: Substrate layer 56: Barrier layer 57: Protective layer 60: Syringe 61: Outer cylinder 62: Tip of the cylinder 63: Gasket 64: Plunger 65: Flange 66: Substrate layer 67: Barrier layer 68: Protective layer

Claims

1. In a container comprising a base material layer, a protective layer provided on at least a part of the surface of the base material layer, and a barrier layer provided between the base material layer and the protective layer, the base material layer contains a thermoplastic resin, When measuring the infrared absorption spectrum by the infrared total reflection measurement method on the surface of the protective layer from the outside of the container, the absorbance at 1340 cm －１ is A １３４０ , and the absorbance at 1720 cm －１ is A １７２０ , when the following relational expression (1): A １３４０ / A １７２０ <0.15 (1) contains a copolymerized polyester satisfying the barrier layer contains a water-soluble or alkali-soluble resin, the container is a vial having a mouth portion, a neck portion, a body portion, and a bottom portion.

2. The container according to claim 1, wherein the protective layer and the barrier layer are provided at least on the neck portion, the body portion, and the bottom portion.

3. In a container comprising a base material layer, a protective layer provided on at least a part of the surface of the base material layer, and a barrier layer provided between the base material layer and the protective layer, the base material layer contains a thermoplastic resin, When measuring the infrared absorption spectrum by the infrared total reflection measurement method on the surface of the protective layer from the outside of the container, the absorbance at 1340 cm －１ is A １３４０ , and when the absorbance at 1720 cm －１ is A １７２０ , the following relational expression (1): A １３４０ / A １７２０ < 0.15 (1) contains a copolymerized polyester satisfying the barrier layer contains a water-soluble or alkali-soluble resin, the container is a syringe having a barrel tip, an outer barrel, a gasket, a plunger, and a flange.

4. The container according to claim 3, wherein the protective layer and the barrier layer are provided at least on the outer barrel.

5. The container according to claim 1 or 3, wherein the thickness of the protective layer is 0.01 μm or more and 200.00 μm or less.

6. When measuring the infrared absorption spectrum by the infrared total reflection measurement method on the surface of the protective layer from the outside of the container, the protective layer has a copolymer polyester having an absorption peak in the range of 1225 cm －１ to 1255 cm －１ with a bimodal peak. The container according to claim 1 or 3.

7. The container according to claim 1 or 3, wherein the barrier layer contains a polyvinyl alcohol-based resin.

8. The container according to claim 7, wherein the barrier layer further contains a carboxyl group-containing resin.

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