Articles and containers

Abstract

To provide a molded article which has excellent heat resistance even in high-temperature sterilization and can be used as an outlet with high strength, and a container equipped with the molded article.SOLUTION: The present invention relates to a molded article 10 having an outlet 13, wherein the cross section of the outlet 13 intersecting the outlet passage 14 has an innermost layer 15 forming the outlet passage 14 and a surface layer 16 forming the outer periphery of the outlet 13; wherein the innermost layer 15 is formed from a resin containing a cyclic olefin resin, a portion of the innermost layer 15 is exposed on the surface layer 16; and wherein the major portion 18 of the surface layer 16 is formed from a resin containing at least polypropylene resin and polyethylene resin.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a molded article and a container. [Background technology]

[0002] Conventionally, soft bags have been known in which medicines or other drugs are filled in containers molded from plastic resins, etc. Patent Document 1 describes a multilayer liquid container having a cyclic olefin resin layer as a sealant for the container made of a multilayer film and as an innermost layer that forms the discharge path of the discharge port, as a material that is neither absorbent nor permeable to medicines.

[0003] Patent Document 2 also describes that in a laminate (sheet) of at least three layers in which a cyclic olefin resin layer, an adhesive layer, and a polypropylene resin layer are laminated in this order, the adhesive layer contains a resin component consisting of linear low-density polyethylene, a styrene-based elastomer, and a polypropylene-based resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-36954 [Patent Document 2] Japanese Patent Application Publication No. 2019-18482 Summary of the Invention [Problem to be solved by the invention]

[0005] The container described in Patent Document 1 has an innermost layer made of a cyclic olefin resin, a surface layer made primarily of metallocene polyethylene, and a discharge port where the cyclic olefin is exposed in a portion of the surface. Furthermore, in the container described in Patent Document 1, the discharge port is welded to a sealant made primarily of a cyclic olefin resin. This prevents adsorption to the resin that forms the discharge port, enables high-temperature steam sterilization, and provides high weld strength. Furthermore, paragraph 0033 of Patent Document 1 states that the incorporation of HDPE (high-density polyethylene) makes it possible to achieve high-temperature sterilization temperatures of 121°C or higher. However, the incorporation of typical HDPE poses issues such as weakening the welded portion and reducing drop strength.

[0006] Furthermore, Patent Document 2 describes a laminate (sheet) including a cyclic olefin resin layer, an adhesive layer, and a polypropylene resin layer. However, there is no particular suggestion regarding a pouring outlet to be provided in a packaging bag formed from this laminate (sheet) (see paragraph 0051 of Patent Document 2). As such, a discharge outlet that is highly suitable for overkill sterilization, which is a high-temperature sterilization treatment at a temperature of 121°C or higher, and has high strength has not been known until now.

[0007] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a molded product that has excellent heat resistance even in high-temperature sterilization treatment and can be used as a discharge outlet with high strength, and a container that includes this molded product. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present invention provides a molded product having a discharge outlet, wherein a cross section of the discharge outlet intersecting the discharge path has an innermost layer that forms the discharge path and a surface layer that forms the outer periphery of the discharge outlet, the innermost layer is formed from a resin containing a cyclic olefin-based resin, a portion of the innermost layer is exposed on the side of the surface layer, and a major portion of the surface layer is formed from a resin that contains at least a polypropylene-based resin and a polyethylene-based resin.

[0009] The resin forming the main part of the surface layer may contain the polypropylene resin in a proportion of 60 to 80% by weight. The resin forming the main part of the surface layer may contain the polyethylene resin in a proportion of 10 to 30% by weight. The resin forming the main part of the surface layer may further contain a styrene-based elastomer in an amount of 5 to 20% by weight.

[0010] The present invention also provides a container in which a liquid storage section formed from a laminate is bonded to the surface layer of the molded product, the laminate having a sealant formed from a resin containing a cyclic olefin resin, and the sealant is bonded to the innermost layer exposed on the surface layer side of the molded product. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a molded article that can be used as a discharge port that has excellent heat resistance even in high-temperature sterilization treatment and has high strength, and a container that includes this molded article. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view showing an example of a molded article and a container according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention will be described below based on preferred embodiments.

[0014] As shown in Fig. 1, a molded article 10 of the embodiment has a discharge port 13. A cross section of the discharge port 13 intersecting with a discharge path 14 has an innermost layer 15 that forms the discharge path 14 and a surface layer 16 that forms the outer periphery of the discharge port 13.

[0015] The innermost layer 15 is formed from a resin containing a cyclic olefin resin. A portion of this innermost layer 15 is exposed on the side of the surface layer 16. In other words, the first layer 11 made of a resin containing a cyclic olefin resin forms the entire innermost layer 15 and a dependent portion 17 that is a portion of the surface layer 16.

[0016] Of the surface layer 16, the main portion 18 excluding the dependent portions 17 is formed from a resin containing at least a polypropylene-based resin and a polyethylene-based resin. That is, the second layer 12 made of a resin containing at least a polypropylene-based resin and a polyethylene-based resin forms the main portion 18 of the surface layer 16. The resin forming the main portion 18 of the surface layer 16 may further contain a styrene-based elastomer.

[0017] A liquid storage portion 20 formed from a laminate 23 is bonded to the surface layer 16 of the molded article 10. A container 30 of this embodiment includes the molded article 10 and the liquid storage portion 20. The laminate 23 has a sealant 21 formed from a resin containing a cyclic olefin resin. The laminate 23 may be in the form of a film, a sheet, a tube, or the like.

[0018] The sealant 21 is bonded to the innermost layer 15 of the molded article 10, which is exposed on the side of the surface layer 16. That is, the first layer 11 of the molded article 10 and the sealant 21 of the liquid storage portion 20 are bonded at least at the dependent portion 17 of the surface layer 16. The laminate 23 may have a substrate 22. The sealant 21 is formed on one side of the substrate 22. The width of the dependent portion 17 to be bonded to the sealant 21 is not particularly limited, but is, for example, in the range of 1 to 20 mm, preferably 2 to 15 mm, and more preferably 3 to 10 mm.

[0019] In the molded article 10 of this embodiment, the resin forming the main portion 18 of the surface layer 16 contains a polypropylene (PP)-based resin. Because polypropylene-based resins have a relatively high melting point, the heat resistance of the entire molded article 10 can be improved by increasing the heat resistance of the main portion 18 of the surface layer 16. It is preferable to select a polypropylene-based resin with a higher melting point or a lower melt flow rate (MFR). In the case of polypropylene-based resins, the MFR can be measured under conditions such as a test temperature of 230°C and a nominal load of 2.16 kg, for example.

[0020] In the molded article 10 of this embodiment, the resin forming the main portion 18 of the surface layer 16 contains a polyethylene-based resin. Examples of polyethylene-based resins include high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE). Ethylene-α-olefin copolymers such as LLDPE are particularly preferred. These polyethylene-based resins have a linear molecular skeleton and incorporate a moderate amount of α-olefin side chains. This facilitates entanglement of the molecular chains of the cyclic olefin-based resin, even if the cyclic olefin-based resin has a bulky molecular structure due to cyclic hydrocarbon groups. The linear portion of the ethylene-α-olefin copolymer is less likely to interfere with the cyclic hydrocarbon groups of the cyclic olefin-based resin, and the side chains of the ethylene-α-olefin copolymer are more likely to intercalate between the cyclic hydrocarbon groups of the cyclic olefin-based resin. This allows for strong welding strength to be achieved between the first layer 11 and the second layer 12.

[0021] In the molded article 10 of this embodiment, the resin forming the main portion 18 of the surface layer 16 contains a styrene-based elastomer. This improves the flexibility and deformability of the main portion 18 of the surface layer 16, and can improve the welding strength between the first layer 11 and the second layer 12, the drop strength of the molded article 10, and the like.

[0022] The resin forming the main portion 18 of the surface layer 16 may contain 60 to 80% by weight of a polypropylene resin. The resin forming the main portion 18 of the surface layer 16 may contain 10 to 30% by weight of a polyethylene resin. The resin forming the main portion 18 of the surface layer 16 may contain 5 to 20% by weight of a styrene elastomer. These proportions may be calculated so that the total of the resin components is 100% by weight, or so that the total of the entire composition including additives is 100% by weight.

[0023] The resin component contained in the main portion 18 of the surface layer 16 may be substantially composed of three components: a polypropylene resin, a polyethylene resin, and a styrene elastomer. The main portion 18 of the surface layer 16 may contain additive components in addition to the resin components.

[0024] In the main portion 18 of the surface layer 16, the total of the three resins consisting of the polypropylene resin, the polyethylene resin, and the styrene elastomer is preferably 90% by weight or more, more preferably 95% by weight or more, and may be 100% by weight. The main portion 18 of the surface layer 16 may contain resin components or additive components other than the three resins, but the proportion thereof is preferably 10% by weight or less, more preferably 5% by weight or less of the entire main portion 18 of the surface layer 16.

[0025] The polypropylene (PP) resin contained in the main portion 18 of the surface layer 16 may be a propylene homopolymer or a copolymer of propylene with ethylene or at least one α-olefin having 4 to 8 carbon atoms. The PP resin may be a propylene copolymer polymerized using a single-site catalyst. Specific examples of comonomers copolymerized into the PP resin include ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. The PP resin may be a random copolymer or a block copolymer. The main portion 18 of the surface layer 16 may contain one type of PP resin, or two or more types of PP resins.

[0026] The polyethylene resin contained in the main portion 18 of the surface layer 16 is copolymerized with an α-olefin having 4 or more carbon atoms and introduced with short-chain branches, thereby imparting a linear molecular structure with few long-chain branches. Examples of α-olefins copolymerized with the polyethylene resin include 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. Olefins other than α-olefins may also be copolymerized with the polyethylene resin. The main portion 18 of the surface layer 16 may contain one type of polyethylene resin, or may contain two or more types of polyethylene resins.

[0027] The polyethylene resin contained in the main portion 18 of the surface layer 16 can be a resin polymerized using a Ziegler-Natta catalyst or a resin polymerized using a single-site catalyst. Polyethylene resins polymerized using a single-site catalyst are preferred because they have a narrow molecular weight distribution and excellent mechanical properties. Examples of single-site catalysts include metallocene catalysts. Examples of metallocene catalysts include catalysts containing a metallocene compound that includes a ligand having a cyclopentadienyl skeleton and in which the metal is zirconium, hafnium, or the like.

[0028] The styrene-based elastomer contained in the main portion 18 of the surface layer 16 may be a copolymer of styrene and an aliphatic olefin. In the molecule of the styrene-based elastomer, a block containing styrene constitutes a hard block, and a block containing an aliphatic olefin constitutes a soft block. The higher the styrene content in the molecule, the stronger the adhesive strength that can be exhibited. However, if the styrene content is too high, flexibility may be impaired. The styrene content in the styrene-based elastomer is, for example, preferably 10 to 50 wt %, more preferably 10 to 30 wt %, and even more preferably 10 to 20 wt %.

[0029] Specific examples of the styrene-based elastomer contained in the main portion 18 of the surface layer 16 include one or more of styrene-ethylene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-isoprene-butadiene-styrene block copolymer (SIBS), styrene-ethylene-butylene-olefin crystalline block copolymer (SEBC), hydrogenated styrene-butadiene rubber (HSBR), etc.

[0030] Among styrene-based elastomers, one or more selected from SEBS, SEPS, SEBC, and HSBR are preferred, with SEBS being particularly preferred. SEBS is generally obtained by hydrogenating a styrene-butadiene-styrene block copolymer to convert a butadiene unit into two ethylene units or a butylene unit, but it may also be one that has been modified or selectively hydrogenated.

[0031] The first layer 11 forming the subordinate portions 17 of the innermost layer 15 and the surface layer 16, and the sealant 21 of the laminate 23 are preferably both formed from a cyclic olefin resin layer containing a cyclic olefin resin. The cyclic olefin resin is a polymer of one or more olefin monomers or a polymer in which the double bonds are hydrogenated, and at least one of the olefin monomers is a cyclic olefin monomer. The cyclic olefin monomer has a cyclic hydrocarbon skeleton.

[0032] The cyclic olefin resin may be a polymer of one type of cyclic olefin monomer, a copolymer of two or more types of cyclic olefin monomers, a copolymer of a cyclic olefin monomer and another monomer, or a hydrogenated product of these polymers or copolymers. Among them, cyclic olefin polymers (COP), cyclic olefin copolymers (COC), etc. are suitable as the cyclic olefin resin.

[0033] Examples of cyclic olefin monomers include bicyclic cycloolefins, tricyclic cycloolefins, tetracyclic cycloolefins, pentacyclic cycloolefins, and hexacyclic cycloolefins. Examples of bicyclic cycloolefins include norbornene, norbornadiene, and substituted derivatives thereof. Examples of tricyclic cycloolefins include dicyclopentadiene, dihydrodicyclopentadiene, and substituted derivatives thereof. Examples of tetracyclic cycloolefins include dimethanohexahydronaphthalene, dimethanooctahydronaphthalene, tetracyclododecene, and substituted derivatives thereof. Examples of pentacyclic cycloolefins include tricyclopentadiene, pentacyclopentadecene, and substituted derivatives thereof. Examples of hexacyclic cycloolefins include hexacycloheptadecene and substituted derivatives thereof. Examples of substituted derivatives of the above-mentioned compounds include one or more alkyl, alkenyl, alkylidene, aryl, etc.

[0034] At least one of the cyclic olefin monomers is preferably a cyclic olefin having a norbornene skeleton (norbornene monomer). Examples of the norbornene monomer include norbornene, dihydrodicyclopentadiene, or compounds in which one or more cyclopentadiene molecules are added to these cyclic compounds by Diels-Alder reaction, hydrogenated products thereof, isomers with different double bond positions, and alkyl-substituted products thereof.

[0035] Cyclic olefin resins having a norbornene skeleton include polymers obtained by hydrogenating the remaining double bonds after ring-opening metathesis polymerization of a norbornene compound, addition polymers composed of two or more norbornene monomers, and addition polymers obtained by copolymerizing a norbornene monomer with another monomer. The other monomer copolymerized with the norbornene monomer may be a cyclic olefin monomer other than a norbornene monomer, a non-cyclic olefin monomer such as ethylene, propylene, or an α-olefin, or a polar monomer such as an acrylic acid ester or a methacrylic acid ester.

[0036] Methods for producing cyclic olefin resins include hydrogenating a ring-opening metathesis polymer of a norbornene compound, copolymerizing two or more cyclic olefin monomers, and copolymerizing a cyclic olefin monomer with an α-olefin.

[0037] Commercially available cyclic olefin resins include "ZEONEX (registered trademark)" and "ZEONOR (registered trademark)" manufactured by Zeon Corporation, "TOPAS (registered trademark)" manufactured by Polyplastics Co., Ltd., "APEL (registered trademark)" manufactured by Mitsui Chemicals, Inc., and "ARTON (registered trademark)" manufactured by JSR Corporation. These cyclic olefin resins have excellent barrier properties and are easily available.

[0038] The cyclic olefin resin layer forming the first layer 11 and the sealant 21 preferably contains a cyclic olefin resin as a main component. For example, the total content of at least one cyclic olefin resin is preferably 50% by weight or more, and more preferably 70% by mass or more. The cyclic olefin resin layer may contain other resin components in addition to the cyclic olefin resin.

[0039] Other resin components that may be contained in the cyclic olefin-based resin layer include one or more of polyolefin-based resins such as polyethylene, polypropylene, polybutene, ethylene-α-olefin copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-vinyl acetate copolymer, and ethylene-(meth)acrylic acid ester copolymer, urethane-based resin, rubber-based resin, polyester-based resin, polyester-urethane-based resin, acrylic resin, amide-based resin, styrene-based resin, and silane-based resin.

[0040] Examples of the styrene-based resin include polystyrene, styrene-acrylonitrile copolymer (SAN), styrene-based elastomer, etc. Among these, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated products thereof (e.g., SEBS, SEPS, etc.), styrene-butadiene random copolymer, etc. are particularly preferred.

[0041] The other resin components contained in the cyclic olefin resin layer are preferably one or more in total within the range of 0.05 to 20% by mass. When the cyclic olefin resin layer contains other resin components, it is possible to improve the desired performance of the container, such as the impact resistance of the container at low temperatures, maintaining transparency immediately after high-pressure steam sterilization, and improving flexibility. The cyclic olefin resin layer may contain additive components in addition to the resin components.

[0042] The cyclic olefin resin layer may contain only a cyclic olefin resin as a resin component. The resin component contained in the cyclic olefin resin layer may be substantially one or more cyclic olefin resins. The cyclic olefin resin layer may contain an additive other than the cyclic olefin resin, or may be formed from a cyclic olefin resin that does not contain any additive.

[0043] The composition of the cyclic olefin resin layer forming the sealant 21 may be the same as or different from the composition of the cyclic olefin resin layer forming the first layer 11 of the molded article 10. The cyclic olefin resin used in the sealant 21 may be the same as or different from the cyclic olefin resin used in the first layer 11 of the molded article 10. From the viewpoint of weldability, it is preferable that the first layer 11 and the sealant 21 contain the same cyclic olefin resin.

[0044] The materials forming each layer that forms the molded product 10 or the liquid storage section 20, i.e., the first layer 11, the second layer 12, the sealant 21, the base material 22, etc., may contain various additives such as antioxidants, ultraviolet absorbers, antistatic agents, lubricants, antiblocking agents, etc., within a range that does not impair safety and hygiene, in order to improve appearance, stabilize quality, and impart other required performance.

[0045] The molded article 10 may have another layer between the first layer 11 including the innermost layer 15 and the second layer 12 forming the main portion 18 of the surface layer 16. Examples of the other layer include a resin layer, an adhesive, and the like. The first layer 11 and the second layer 12 may be directly bonded without an intervening layer. The method for manufacturing the molded article 10 is not particularly limited, and any conventionally known molding method can be used. For example, two-color molding or multi-color molding, in which two or more resin layers are molded simultaneously, may be used, or insert molding, in which each layer is molded sequentially. In the case of insert molding, the first layer 11 including the innermost layer 15 may be molded first, followed by molding the main portion 18 of the surface layer 16, or the first layer 11 including the innermost layer 15 may be molded after molding the main portion 18 of the surface layer 16.

[0046] The laminate 23 forming the liquid storage portion 20 may have a two-layer structure of a sealant 21 and a substrate 22, or may have other layers laminated thereon as needed. An adhesive layer or an anchor agent layer may be interposed between the layers of the laminate 23, or the layers may be laminated so as to be in direct contact with each other. Examples of other layers include one or more of a reinforcing layer, a barrier layer, a light-shielding layer, a printed layer, etc.

[0047] The sealant 21 is a layer used for heat sealing the laminate 23, and as a packaging material, is disposed as the innermost layer that comes into contact with the contents. The sealant 21 is used to bond the laminate 23 to the molded article 10. When the laminate 23 is a film, sheet, or the like, the sealant 21 may be used to bond the laminates 23 together. Heat sealing is a method of bonding by melting the sealant 21. There are no particular restrictions on the sealing method, and examples include hot plate sealing, ultrasonic sealing, high-frequency sealing, and impulse sealing. As mentioned above, the sealant 21 is preferably a cyclic olefin resin.

[0048] The substrate 22 of the laminate 23 is not particularly limited, and examples thereof include films formed from polyolefin resins such as polyethylene and polypropylene, polyamide resins such as nylon, and polyester resins such as polyethylene terephthalate (PET). The laminate 23 may have only one layer of substrate 22. The laminate 23 may have two types or two or more layers of substrate 22. The substrate 22 may be the outermost surface of the laminate 23, which is the side opposite to the sealant 21. The laminate 23 may have another layer outside the substrate 22.

[0049] The barrier layer of the laminate 23 is a layer that imparts barrier properties such as oxygen barrier properties and water vapor barrier properties. Barrier materials that can be used for the barrier layer include ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyvinylidene chloride, nylon obtained by polycondensing metaxylenediamine (MXDA) with a polycarboxylic acid, fluorine-based resin, alumina, and silica. When the barrier material is a resin, it may be a barrier film or a barrier coating. When the barrier material is an inorganic compound, it may be a vapor-deposited film obtained by vapor-depositing an inorganic compound onto a resin film. When the barrier material is a metal, it may be a vapor-deposited film obtained by vapor-depositing a metal onto a resin film, or a metal foil.

[0050] The method for producing the laminate 23 is not particularly limited, and examples thereof include extrusion lamination, dry lamination, co-extrusion, etc., or a combination of two or more methods. The co-extrusion method may be multi-layer T-die casting or multi-layer inflation molding.

[0051] The total thickness of the laminate 23 is not particularly limited, but may be, for example, 50 to 400 μm. The thickness of the sealant 21 is, for example, preferably 5 to 150 μm, and more preferably 15 to 100 μm.

[0052] Examples of containers that form the liquid storage portion 20 include packaging bags (pouches), tube packaging, etc. The liquid storage portion 20 is provided with at least one molded article 10 having an outlet 13. The outlet 13 can also be used as a filling port, an air vent, etc. The method for forming the liquid storage portion 20 from the laminate 23 is not particularly limited, but examples include heat sealing, blow molding, etc.

[0053] When heat-sealing the laminate 23 to the molded article 10, the molded article 10 may be inserted between two overlapping laminates 23 with the sealant 21 on the inside and heat-sealed. When inserting the molded article 10 between two overlapping laminates 23, boat-shaped fusion bases may be provided on both sides of the discharge channel 14. This allows the two laminates 23 to gradually approach each other along the boat-shaped fusion bases until they are heel-sealed to each other at a location where the molded article 10 is not inserted. A flange-shaped fusion base may be provided at the end of the molded article 10, and this flange-shaped fusion base may be heat-sealed to the periphery of a hole provided in the laminate 23.

[0054] The tip of the outlet 13 may be open when the molded article 10 is joined to the liquid storage portion 20. After the liquid storage portion 20 is filled with the contents, an inner stopper, cap, etc. may be attached to the outlet 13. A portion of the heat seal formed on the periphery of the liquid storage portion 20 may be omitted, and after the contents are filled through the unsealed portion, the unsealed portion may be closed by heat sealing. If the outlet 13 is not used for filling the contents, the outlet 13 may be closed with an inner stopper, cap, etc. before the molded article 10 is joined to the liquid storage portion 20.

[0055] The container 30 of this embodiment can be suitably used as a container for storing medicines, food and beverages, cosmetics, etc. The medicines may be substances that have high adsorption or permeability to general resins, such as nitroglycerin, albumin, vitamins, trace elements, and radical scavengers. The container 30 can be suitably used for storing medical liquids. The use of the container 30 makes it possible to apply high-temperature sterilization treatment at temperatures preferably above 105°C, more preferably above 115°C, and particularly preferably above 121°C.

[0056] The form of the packaging bag forming the liquid storage section 20 can be any form, including small packaging bags (pouches) such as three-sided bags, four-sided bags, seamed bags, gusseted bags, and self-standing bags, as well as large bags such as inner bags for bag-in-boxes and interior bags for drums, without any particular limitations.

[0057] The present invention has been described above based on preferred embodiments, but the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present invention. [Example]

[0058] The present invention will be specifically described below with reference to examples.

[0059] (manufacturing of molded products) The resins shown in Tables 1 and 2 were used to prepare the resins forming the main part of the surface layer, and together with the cyclic olefin resin for the innermost layer, a molded product having an outlet was manufactured by two-color molding. The resins used for the main part of the surface layer are as follows.

[0060] (Polypropylene resin) "WMG03": Product name of Japan Polypropylene Corporation: Wintec (registered trademark) WMG03, MFR (JIS K7210): 30.0 g / 10 min, density 0.900 g / cm 3 , flexural modulus 1250MPa, tensile modulus 1300MPa, tensile yield stress 30MPa, tensile elongation over 200%, melting point 142℃. "7055": Trade name of Mitsubishi Chemical Corporation: ZELAS (registered trademark) 7055, MFR (230°C, 21N): 7.0 g / 10 min, density 0.890 g / cm 3 , flexural modulus 550MPa, tensile strength 40MPa, tensile elongation 650%, melting point 162℃. "MC642": Mitsubishi Chemical Corporation product name: MC642, MFR 20.0 g / 10 min, density 0.890 g / cm 3 , flexural elasticity 560MPa, tensile strength 29MPa, tensile elongation 680%, melting point 134℃. "AR244M": Trade name of Sumitomo Chemical Co., Ltd.: Excellen (registered trademark) AR244M, MFR 25.0 g / 10 min, density 0.895 g / cm 3 , flexural modulus 1300MPa, tensile yield stress 32MPa, tensile elongation 350%, melting point 157℃.

[0061] (Polyethylene resin) "140HK": Ube Maruzen Polyethylene Co., Ltd. product name: Yumerit (registered trademark) 140HK, MFR (JIS K7210): 3.5 g / 10 min, density 0.937 g / cm 3 , flexural modulus 760MPa, tensile strength 37MPa, tensile elongation 780%, melting point 126℃. "FY11": Tosoh Corporation's product name: Nipolon (registered trademark) Z FY11, MFR 1.1 g / 10 min, density 0.930 g / cm 3, flexural modulus 360MPa, tensile modulus 390MPa, tensile yield stress 13MPa, tensile strength 21MPa, tensile elongation 460%, melting point 130℃. "FY13": Tosoh Corporation's product name: Nipolon (registered trademark) Z FY13, MFR 1.1 g / 10 min, density 0.950 g / cm 3 , flexural modulus 783MPa, tensile modulus 826MPa, tensile yield stress 22MPa, tensile strength 15MPa, tensile elongation 250%, melting point 133℃.

[0062] (styrene elastomer) "G1657MS": Kraton Polymers trade name: Kraton (registered trademark) G1657MS, styrene-based elastomer (SEBS).

[0063] (Container manufacturing) A liquid storage portion was made using a sheet with a cyclic olefin resin as a sealant, and the molded product manufactured as described above was heat-sealed to produce a container. The container was filled with a test aqueous solution as the content, sealed, and sterilized at a temperature of 121°C for 25 minutes.

[0064] (Seal strength measurement) The seal strength (N / 15mm) between the molded product and the sheet of the liquid storage section was measured for the container before and after sterilization. For each sample of the same type, multiple containers were prepared before and after sterilization, and the average value of n=6 was used to measure the seal strength.

[0065] (Evaluation of deformation of molded products due to sterilization) The deformation of the molded product after sterilization was visually checked and rated in three ways: "○" (no deformation), "△" (slight deformation), and "×" (large deformation).

[0066] The results are shown in Tables 1 and 2. In Tables 1 and 2, A is polypropylene resin (PP component), B is polyethylene resin (PE component), and C is styrene elastomer. The ratio of A:B:C is weight ratio (%). "Before sterilization" and "after sterilization" respectively represent the seal strength (N / 15 mm) between the molded product and the liquid storage section. The "seal strength ratio" is the ratio calculated by (seal strength after sterilization / seal strength before sterilization) x 100%.

[0067] [Table 1]

[0068] [Table 2]

[0069] A comparison of Examples 1 to 6 (with the same weight ratio of A:B:C) revealed that even if the PE component was the same, a different PP component affected the performance of the molded product. For example, in Examples 2 to 4, when the melting point of the PP component was 150 to 170°C and the MFR of the PP component was 5 to 10 g / 10 It is considered that a time of about min is preferable. Furthermore, a comparison of Example 4 with Examples 7 to 11 revealed that the performance of the molded article is affected by differences in the weight ratio of A:B:C. For example, as in Examples 4, 7, 8, and 11, it is considered preferable to contain a styrene-based elastomer in a proportion of about 5 to 20% by weight. [Explanation of symbols]

[0070] 10...molded article, 11...first layer, 12...second layer, 13...discharge outlet, 14...discharge path, 15...innermost layer, 16...surface layer, 17...subordinate portion of surface layer, 18...main portion of surface layer, 20...liquid storage portion, 21...sealant, 22...substrate, 23...laminated body, 30...container.

Claims

1. A molded article having a discharge port, a cross section of the discharge port intersecting the discharge path has an innermost layer that forms the discharge path and a surface layer that forms an outer periphery of the discharge port, the innermost layer is formed from a resin containing a cyclic olefin resin, and a part of the innermost layer is exposed on the surface layer side; A molded article characterized in that a main portion of the surface layer is formed from a resin containing at least 60 to 80% by weight of a polypropylene-based resin and 10 to 30% by weight of a polyethylene-based resin, and the polypropylene-based resin has a melting point of 150 to 170°C and a melt flow rate (MFR) of 5 to 10 g / 10 min.

2. 2. The molded article according to claim 1, wherein the resin forming the main portion of the surface layer further contains 5 to 20% by weight of a styrene-based elastomer.

3. A container in which a liquid storage portion formed of a laminate is joined to the surface layer of the molded article according to claim 1 or 2, the laminate has a sealant formed from a resin containing a cyclic olefin resin, A container characterized in that the sealant is bonded to the innermost layer exposed on the surface layer side of the molded product.

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