High-purity chemical solution-loading multilayer resin container

Abstract

Provided is a high-purity chemical solution-loading multilayer resin container that exhibits high-performance, that can be loaded with a high-purity chemical solution in a volume from about 100 mL to 4 L, that hardly breaks due to having excellent impact resistance, that can be inexpensively and easily manufactured at a high quality so as to have a uniform thickness, particularly a uniform thickness in an inner layer, and that not only has excellent gas barrier properties but also does not elute or release fine impurity particles in a content.　This high-purity chemical solution-loading multilayer resin container is to be loaded with a high-purity chemical solution in an inner space thereof, and has, laminated therein sequentially from the inner space side to the outer circumference side: an inner layer made of a cyclic polyolefin; an adhesive layer containing a maleic anhydride-modified polyethylene; a barrier layer made of an ethylene-vinyl alcohol copolymer; another adhesive layer containing a maleic anhydride-modified polyethylene; and an outer layer made of a high density polyethylene that has a density of 0.945-0.965 g / cm3 and a melt flow rate (190°C, 21.18 N load) of 0.5 g / 10 min or less.

Description

Multilayer resin container for filling high-purity chemical liquids

[0001] The present invention relates to a resin multilayer container for filling with high-purity chemical liquids, which are filled with high-purity chemical liquids that must be maintained at high quality, and transported or stored.

[0002] High-purity chemicals such as photoresist solutions, high-purity chemicals for semiconductor manufacturing, and high-purity chemicals for microanalysis are transported and stored in containers, which are generally made of metal, glass, or resin.

[0003] Among these, metal containers have excellent gas barrier properties. However, they are heavy and prone to rusting due to the liquid or dissolved oxygen, contaminating the liquid, or leaching out metal ions. Furthermore, when metal containers are made thin to reduce weight, their impact strength decreases and they become easily deformed.

[0004] Glass containers are transparent, making it easy to see the state of the filled liquid, inexpensive, and have excellent gas barrier properties.However, they are heavy and easily broken, and if the filled liquid is a high-purity chemical, they will leach impurities such as fine particles and metal ions, contaminating the liquid, making them unsuitable for use with high-purity chemicals used in semiconductor manufacturing.

[0005] On the other hand, plastic containers are lightweight, shatter-resistant, and easily moldable. Polyethylene is widely used as the raw material for these containers because of its non-elution of impurities, ease of molding, availability, economical efficiency, and environmental friendliness.

[0006] However, the gas barrier properties of polyethylene containers may be reduced depending on the type of liquid filled in them, and the liquid may evaporate and leak from the polyethylene container, resulting in a decrease in volume, a change in composition, or a negative pressure inside the container, causing deformation of the container. Therefore, containers made by dry-blending a powdered gas barrier agent into polyethylene and then blow-molding the mixture are widely used. However, even when such a powdered gas barrier agent is dry-blended, it is merely scattered throughout the polyethylene, so the improvement in gas barrier properties may be insufficient.

[0007] For this reason, containers that have been given gas barrier properties by blow molding a multilayer structure of a polyethylene layer and a gas barrier layer are used. However, it is known that when polyethylene containers are used in areas that come into contact with the filled drug solution, they may adsorb certain drugs, such as fat-soluble vitamins, and the concentration of the specific drugs may decrease during storage.

[0008] In response to these challenges, containers made of cyclic polyolefin resins are known, which inhibit the adsorption and absorption of specific drugs, and which are excellent in transparency, heat resistance, deformation resistance, hygienic properties, and other properties, as well as having high barrier properties such as low water vapor transmission. For example, Patent Document 1 discloses, as described in claims 1 and 2, a multilayer container laminated, from the outside, with an outer layer, an adhesive layer containing a cyclic polyolefin resin graft-polymerized with maleic anhydride and an antioxidant, a barrier layer containing an ethylene-vinyl alcohol copolymer, another adhesive layer, and an inner layer containing a cyclic polyolefin resin. The examples describe the production of vial-shaped multilayer containers with a capacity of 5 to 100 mL.

[0009] For semiconductor manufacturing chemicals such as photoresist solutions, cleaning solutions, and etching solutions, as well as chemicals for diagnostic equipment and analytical solutions, there is a demand for multilayer containers for relatively medium volumes of high purity chemicals, approximately 500 mL to 4 L, at the laboratory reagent level, as well as at manufacturing sites and clinical analytical sites, so that they can be used up once or within a short period of time to prevent the introduction of impurities, fluctuations in composition, or deterioration. According to the inventors' studies, conventional multilayer containers having an inner layer containing a cyclic polyolefin resin, such as those described in Patent Document 1, can withstand drop tests if they are in the form of a vial of 100 mL or less, as described in the examples. However, it was found that attempts to manufacture multilayer containers with volumes greater than this can result in drawdown of the inner layer during the manufacturing process, making it difficult to control the thickness, resulting in poor impact resistance and cracks during drop tests, or an inconsistent thickness, which can lead to uneven thickness of the inner layer, making it impossible to guarantee the quality of the contents, or even making the container impossible to manufacture at all.

[0010] Japanese Patent Application Laid-Open No. 2017-30765

[0011] The present invention has been made to solve the above-mentioned problems, and aims to provide a high-performance resin multi-layer container for filling with high-purity chemical liquids, which can be filled with high-purity chemical liquids in volumes exceeding 100 mL up to a maximum of approximately 4 L, has excellent impact resistance and is difficult to break, has a uniform thickness, particularly the inner layer, can be manufactured inexpensively and simply with high quality, and not only has excellent gas barrier properties but also does not leach or release impure fine particles into the contents.

[0012] The resin multilayer container for filling with high-purity chemical liquids according to the present invention, which has been made to achieve the above-mentioned object, is a resin multilayer container for filling a high-purity chemical liquid into an inner space thereof, and comprises, in order from the inner space side to the outer periphery side thereof, an inner layer made of a cyclic polyolefin, an adhesive layer containing maleic anhydride-modified polyethylene, a barrier layer made of an ethylene-vinyl alcohol copolymer, another adhesive layer containing maleic anhydride-modified polyethylene, and a polyolefin resin having a density of 0.945 to 0.965 g / cm ３ and an outer layer made of high-density polyethylene having a melt flow rate (190°C, 21.18 N load) of 0.5 g / 10 min or less, and the inner space has a volume of more than 100 mL and 4 L or less.

[0013] The inner layer of this resin-made multi-layer container for filling high-purity chemical solutions may be made of the cyclic polyolefin having a melt flow rate (280°C, 21.18 N load) of 6 g / 10 min or more and 60 g / 10 min or less and / or an Izod impact strength in accordance with ASTM D256 of 18 J / m or more and 60 J / m or less.

[0014] This resin-made multilayer container for filling with high-purity chemical liquids has an opening in the inner space for filling or discharging the high-purity chemical liquid, a cap that closes the opening is screwed on and / or inserted, and it is even more preferable that the inner top surface of the cap has a gasket made of the same type of cyclic polyolefin that closes the opening.

[0015] In this resin-made multi-layer container for filling high-purity chemical solutions, the upper end of the opening and the inner periphery connected thereto are preferably covered with a layer extending from the inner layer made of cyclic polyolefin.

[0016] The resin multilayer container of the present invention for filling high-purity chemical liquids can be filled stably for a long period of time with relatively medium volumes of high-purity chemical liquids, exceeding 100 mL and up to approximately 4 L, without alteration or deterioration, while maintaining high quality.It not only has excellent gas barrier properties, but also does not cause the leaching or release of impure fine particles into the contents.

[0017] Furthermore, by suppressing drawdown during the production of multi-layer containers made of resin for filling high-purity chemical solutions, it is possible to achieve a uniform thickness, particularly of the inner layer, and therefore the multi-layer containers, particularly the inner layer, can be homogenized, resulting in high-quality products with good yield and production efficiency, and can be obtained inexpensively and simply.

[0018] Such a resin multilayer container for filling high-purity chemical solutions has a relatively medium capacity, but has impact resistance and durability comparable to that of a small-capacity container, while also providing the same level of convenience of use as a large-capacity container, making it a highly functional container.

[0019] 1 is a partially cutaway front view showing a multilayer resin container for filling with high-purity chemical solutions to which the present invention is applied.

[0020] Hereinafter, embodiments for carrying out the present invention will be described in detail, but the scope of the present invention is not limited to these embodiments.

[0021] 1, a preferred embodiment of the resin multilayer container 1 for filling high-purity chemical liquids of the present invention will be described. This resin multilayer container 1 is for filling an inner space 20 with a high-purity chemical liquid 21, and comprises a container body 10 having, in order from the inner space 20 side to the outer periphery 1a side, an inner layer 11 made of a cyclic polyolefin, an intermediate layer 13 which is a barrier layer made of an ethylene-vinyl alcohol copolymer, and an outer layer 15 made of high-density polyethylene. Between the inner layer 11 and the intermediate layer 13, and between the intermediate layer 13 and the outer layer 15, which constitute the container body 10, adhesive layers 12, 14 containing maleic anhydride-modified polyethylene of the same or different composition are provided (see the enlarged cross-sectional schematic view of the container body 10 in the same figure).

[0022] The resin multilayer container 1 for filling with high-purity chemicals has an opening 17 for filling or discharging a high-purity chemical 21 into or from an inner space 20. A male screw 19 is provided around the opening 17. The opening 17 has an inner layer 11, an adhesive layer 12, an intermediate layer 13, a separate adhesive layer 14, and an outer layer 15 as part of the container body 10 up to the mouth 18, but at the mouth 18, the upper end and the inner layer connected to it are covered with an extension layer 11a extending from the inner layer made of cyclic polyolefin.

[0023] This resin-made multilayer container 1 for filling with high-purity chemical liquids has a cap 30 that closes the mouth 18 of the opening 17 of the resin-made multilayer container 1 for filling with high-purity chemical liquids. The inside of the cap 30 is recessed, and a female screw 39 that threads onto the male screw 19 of the opening 17 is provided in the recess. The cap 30 has a gasket 31 on its inner top surface that closes the opening 18 and is made of the same or a different cyclic polyolefin as the inner layer 11 of the container body 10. The gasket 31 has a disk-shaped gasket base plate 31a and an annular protrusion 31b on its underside that fits into the mouth 18 of the opening 17. The outer diameter of the annular protrusion 31b is approximately the same as the inner diameter of the opening 17, allowing the annular protrusion 31b of the gasket 31 to fit into the opening 17 of the container body 10. The gasket 31 is engaged by a plurality of ring-shaped or intermittent claws that protrude slightly below the inner top surface of the cap 30. This allows the cap 30 to be screwed onto the outer periphery of the opening 17 of the container body 10, and / or the annular protrusions 31b to be inserted along the inner periphery of the opening. Anti-slip portions 33 may be provided at equal intervals on the outer periphery of the cap. The packing 31 may be separable from the cap 30, or may be fused to the cap 30 to form an integrated unit.

[0024] This allows the high-purity chemical liquid 21 to come into contact only with the inner layer of the container body 10 and the packing 31 of the cap.

[0025] The layer thicknesses of the inner layer 11, adhesive layer 12, intermediate layer 13, another adhesive layer 14, and outer layer 15 are (50 to 500 μm): (30 to 100 μm): (30 to 100 μm): (30 to 100 μm): (300 to 2,000 μm).

[0026] The outer layer 15 has a density of 0.945 to 0.965 g / cm ３ and is made of high-density polyethylene (HDPE) having a melt flow rate (190°C, 21.18 N load) of 0.5 g / 10 min or less. When outer layer 15 is made of high-density polyethylene having such physical properties, combined with the fact that inner layer 11, even if made of cyclic polyolefin, has specific physical properties as described below and is strongly bonded to barrier layer 13 and outer layer 15 via adhesive layers 12, 14 containing maleic anhydride-modified polyethylene, it is possible to suppress or prevent drawdown of the inner layer or all layers during blow molding, and as a result, it becomes possible to produce a resin-made multilayer container 1 for filling with high-purity chemical liquids having a relatively medium capacity of more than 100 mL up to about 4 L, which has excellent impact resistance and sufficient strength to be resistant to cracking even when filled with high-purity chemical liquid 21 as a content after production, and is therefore excellent in durability.

[0027] It is further preferable that this resin multilayer container for filling with high-purity chemical solutions has a drop strength that does not break or leak in a drop test in which a container filled with water and stored at room temperature or a container filled with antifreeze solution and stored at -19°C or below is dropped from a height of 1.2 m.

[0028] Specifically, the high density polyethylene for forming the outer layer 15 has a density of 0.951 g / cm ３ and a resin having a melt flow rate (190° C., 21.18 N load) of 0.18 g / 10 min.

[0029] Specifically, the maleic anhydride-modified polyethylene for forming the adhesive layer 14 between the outer layer 15 and the intermediate layer 13 has a density of 0.915 g / cm ３ and a melt flow rate (190°C, 21.18 N load) of 1.4 g / 10 min.

[0030] The intermediate layer 13 contains an ethylene-vinyl alcohol copolymer in order to exhibit barrier properties.

[0031] The intermediate layer 13 has a resistance to oxygen of 0.2 to 0.7 g / m under conditions of 20°C and 65% RH in order to prevent the high-purity chemical liquid 21 to be filled from volatilizing and permeating the resin-made multilayer container 1 for filling with high-purity chemical liquid. ２ It has gas barrier properties such as / day.

[0032] Specifically, the intermediate layer 13 is made of an ethylene-vinyl alcohol copolymer, which is a raw material for exhibiting barrier properties, and has a density of 1.19 g / cm ３ A resin having a melt flow rate (190° C., 21.18 N load) of 1.6 g / 10 min and an ethylene copolymerization ratio of 32 mol % can be used.

[0033] The maleic anhydride modified polyethylene for forming the adhesive layer 12 between the inner layer 11 and the intermediate layer 13 may be the same as or different from the examples given for the adhesive layer 14 between the outer layer 15 and the intermediate layer 13 .

[0034] The inner layer 11 is made of a cycloolefin polymer (COP), which is a homopolymer or copolymer having repeating units with a cyclic skeleton.

[0035] Such cyclic polyolefins include those represented by the following chemical formulas (1) to (6), and are roughly classified into those made from norbornenes as raw materials and those made from cyclic or acyclic dienes, such as cyclopentadienes, cyclohexadienes, or 1,3-butadienes as raw materials.

[0036]

[0037] More specifically, examples of cyclic polyolefins exemplified by the chemical formula (1) include, for example, random addition or block addition copolymers of norbornene monomers and α-olefin monomers (in formula (1), R １ , R ２ and R ３are the same or different and each represents a linear, branched, and / or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group, or a 5- to 7-membered fused ring (including a cyclohexane ring, a cycloheptane ring, or a norbornane ring), or a hydrogen atom; n1 and n2 are 1 or more and are the numbers that form a repeating unit of an addition copolymer, provided that adjacent repeating units may be head-to-tail, head-to-head, or tail-to-tail (the same applies hereinafter); or a homopolymer obtained by random addition or block addition of norbornene monomers (in formula (1), R １ ~R ２ is the same as above, n1 is the number of repeating units of the addition homopolymer, and n2 is 0).

[0038] Alternatively, the cyclic polyolefin represented by the chemical formula (2), for example, using highly reactive norbornenes as raw material monomers, may be an addition copolymer in which norbornene monomers are randomly polymerized by ring-opening hydrogenation metathesis or every few repeating units or all repeating units are block polymerized (in formula (2), R ４ ~R ５ is the R １ ~R ２ and n3 is the number of repeating units forming the addition homopolymer).

[0039] Alternatively, a copolymer (R in formula (3)) obtained by hydrogenating a polymer obtained by random or block addition polymerization of a cyclopentadiene monomer at the 1,2- and 1,4-positions as a cyclic polyolefin represented by the chemical formula (3), for example, using a highly reactive cyclopentadiene as a raw material monomer, may be used. ６ ~R ８ is the R １ ~R ３ and n4 and n5 are the numbers of repeating units forming the addition copolymer).

[0040] Alternatively, a copolymer (R in formula (4)) obtained by hydrogenating a polymer obtained by random or block addition polymerization of cyclohexadiene monomers at the 1,2- and 1,4-positions is used as a cyclic polyolefin represented by the chemical formula (4), for example, using highly reactive cyclohexadienes as raw material monomers. ９ ~R１２ is the R １ ~R ３ and n6 and n7 are the numbers of repeating units forming the addition copolymer).

[0041] Alternatively, the cyclic polyolefin represented by the chemical formula (5), for example, using highly reactive alkylidene norbornenes as raw material monomers, may be an addition copolymer in which alkylidene norbornene monomers are randomly polymerized by transannular polymerization or in which every few repeating units or all repeating units are block polymerized (in formula (5), R １３ ~R １４ is the R １ ~R ３ and n8 is the number of repeating units forming the addition homopolymer).

[0042] Alternatively, the cyclic polyolefin represented by the chemical formula (6) may be, for example, a highly reactive butadiene monomer, such as a random or block polymer cyclized after 1,2-polymerization of butadiene monomer (in formula (6), R １５ is the R １ ~R ３ and n9 is the number of repeating units of the polymer).

[0043] Such cyclic polyolefins have the required properties of transparency, low birefringence, low moisture absorption deformation, and heat resistance that are as excellent as glass, and are widely used for resin containers.They are superior as the inner layer 11 of a resin multilayer container 1 for filling high-purity chemical solutions to methacrylic resin (PMMA), which is extremely poor in the required properties of low moisture absorption, polycarbonate (PC), which is extremely poor in the required properties of low birefringence and low moisture absorption, and polystyrene (PS), which is extremely poor in low birefringence and heat resistance, and have moldability that is equal to or better than these transparent plastics.

[0044] Such cyclic polyolefins preferably have a melt flow rate (hereinafter abbreviated as MFR) of 6 g / 10 min or more and 60 g / 10 min or less, as measured by an encoder in accordance with JIS K7210-1 (2014), under measurement conditions of 280°C and a load of 21.18 N. If the MFR exceeds this range, when the resin-made multilayer container 1 for filling high-purity chemical solutions is formed by thermoplastic blow molding by heating to about 200 to 280°C, the cyclic polyolefin-containing raw material composition for the inner layer 11 will melt or soften excessively due to heat during extrusion, causing drawdown and making the inner layer 11 too thin or uneven, or making it impossible to form the inner layer in parts.

[0045] On the other hand, if the MFR is below this range, when the resin-made multilayer container 1 for filling high-purity chemical liquids is heated by blow molding to form it by thermoplasticity, the cyclic polyolefin-containing raw material composition for the inner layer will not melt or soften completely, making it impossible to form tightly adhered layers or to form layers of uniform thickness.

[0046] On the other hand, if the MFR is within this range, the resin melts or softens appropriately during blow molding and does not draw down too much, so that the density of the outer layer is 0.945 to 0.965 g / cm ３ Since the container is made of high-density polyethylene with an MFR of 0.5 g / 10 min or less at 190°C and a load of 21.18 N, it has extremely little thermal deformation, which makes it possible to suppress or prevent drawdown of the inner layer during blow molding. As a result, it is possible to manufacture a resin multilayer container 1 for filling high-purity chemical solutions with a relatively medium volume of more than 100 mL up to a maximum of about 4 L, which has excellent impact resistance and sufficient strength to prevent cracking even when filled with contents after manufacture, and is therefore highly durable.

[0047] If such a cyclic polyolefin further has the physical property of an Izod impact strength of 18 J / m or more and 60 J / m or less according to ASTM D256, it is possible to obtain a container with high impact resistance when dropped, etc. However, since toughness decreases as the impact strength value increases, the aforementioned value range is preferable in consideration of the balance between impact strength and toughness.

[0048] Specific examples of the cyclic polyolefin used to form the inner layer 11 include ZEONOR 1020R and 1420R (both trade names manufactured by Zeon Corporation).

[0049] The cleanliness index indicates the degree of quality degradation due to the elution of impurity particles during long-term storage of high-purity chemical solution 21 in container body 10. The cleanliness index is determined by calculating the number of particles with a particle size of 0.1 μm or more present in 1 mL of the stored content after storing ultrapure water or photoresist solution in a test container for a certain period of time. Specifically, it is defined by the following formula:

[0050]

[0051] In formula (1), a is the volume of the resin multilayer container 1 for filling with high-purity chemicals, and b is the amount of liquid sampled from the resin multilayer container 1 for filling with high-purity chemicals. First, a sample liquid for measuring the initial cleanliness level is collected as follows: Half the volume (a / 2 mL) of a high-purity chemical liquid 21 for measuring the cleanliness level, which is at least one selected from photoresist liquid, semiconductor manufacturing chemicals, elution liquid, and analytical chemicals, or ultrapure water for measuring the cleanliness level, is filled into a resin multilayer container 1 for filling with high-purity chemicals, with a volume a (mL). The container is then fitted with a cap 30, shaken for 15 seconds, and allowed to stand for 24 hours before being sampled. A sample liquid for measuring the cleanliness level after storage is collected after the initial cleanliness level measurement by fitting the cap 30 to the container and leaving it for a certain period of time. The container 1 is rotated three times to prevent the generation of bubbles. c is the value obtained by counting the number of fine particles with a particle diameter of 0.1 μm or more in the total amount of sample liquid using a particle counter. Based on this value, the initial cleanliness and cleanliness after a certain period of storage are calculated using equation (1). A lower cleanliness value indicates better quality of the high-purity chemical or ultrapure water. This resin multilayer container for filling high-purity chemicals preferably has a cleanliness of 10 particles / mL or less, which indicates the number of impure particles with a particle size of 0.1 μm or more in the high-purity chemical and / or water. A cleanliness of 10 particles / mL or less allows stable storage of the high-purity chemical 21, which is a semiconductor manufacturing chemical selected from photoresist solutions, cleaning solutions, and etching solutions, to prevent a decrease in the quality and yield of manufactured semiconductors, liquid crystal displays (LCDs), etc., and also prevents contamination of the test liquid or increased measurement errors when the high-purity liquid is a chemical for liquid chromatography or liquid chromatography / MS, a chemical for analysis, etc.

[0052] The container body 10 of this multi-layer resin container 1 for filling high-purity chemical solutions is manufactured, for example, using a commercially available multi-layer blow molding machine. The blow molding machine uses, for example, a two-piece mating mold that is symmetrical in appearance except for the male screw 19. This mold has a cavity shaped to correspond to the outer shape of the container.

[0053] This method for producing a resin multi-layer container for filling high-purity chemical liquids is a method for producing a resin multi-layer container for filling a high-purity chemical liquid into an inner space, and includes, in order from the inner space side to the outer periphery side, an inner layer made of a cyclic polyolefin, an adhesive layer containing maleic anhydride-modified polyethylene, a barrier layer made of an ethylene-vinyl alcohol copolymer, another adhesive layer containing maleic anhydride-modified polyethylene, and a resin having a density of 0.945 to 0.965 g / cm ３ The laminate is formed by laminating an outer layer made of high-density polyethylene having a melt flow rate (190° C., 21.18 N load) of 0.5 g / 10 min or less to the outer layer made of high-density polyethylene, and then by blow molding.

[0054] A multilayer pipe-shaped parison is molded using an extruder. The multilayer parison is composed of an inner layer 11 of cyclic polyolefin, an adhesive layer 12 containing maleic anhydride-modified polyethylene, an intermediate layer 13 of ethylene-vinyl alcohol copolymer, another adhesive layer 14 containing maleic anhydride-modified polyethylene, and an outer layer 15 of high-density polyethylene. The hot multilayer parison is clamped to a point where it protrudes from the mold, and the protruding parison is pulled out and cut off. At the same time, the parison is expanded with air to fill the cavity of the mold, resulting in the container body 10. When cutting off the parison, a blow pin is driven into the opening 17, cutting it so that the inner layer expands outward. This causes the inner layer 11 to cover the opening 18 of the opening 17 with an extension layer 11a extending from the cyclic polyolefin inner layer. As a result, the upper end of the opening 17 and the inner layer connected to it are covered with the extension layer 11a.

[0055] The cap of this resin-made multilayer container 1 for filling high-purity chemical liquids consists of a cap body and a gasket 31. The cap body is manufactured using, for example, a commercially available injection molding machine. A mold that forms the desired shape is used in the molding machine. This mold forms a cavity that forms the outer shape of the cap 30, the inner recess, and the female screw 39 and claws 32. A polyolefin resin composition is injection molded into the cavity of this molding machine to form the cap body. Meanwhile, the gasket 31 is manufactured using, for example, a commercially available injection molding machine. This molding machine is one that integrally molds, for example, a gasket base plate 31a and annular protrusion 31b. It is preferable that the gasket has an annular protrusion that fits into the annular opening. A mold that forms the desired shape is used to manufacture the cap. This mold forms a cavity that forms the cap 31. A cyclic polyolefin resin composition is injection molded into the cavity of this molding machine to form the gasket 31.

[0056] Below, we will describe in detail the manufacturing methods and evaluation results of an example in which a multilayer container made of resin for filling high-purity chemical solutions to which the present invention is applied was prototyped, and a comparative example in which a multilayer container to which the present invention is not applied was prototyped.

[0057] Example 1 The following materials were used in the order of lamination for a multi-layer container made of resin for filling with high-purity liquid chemicals and having a cap. (Container body of multi-layer container made of resin for filling with high-purity liquid chemicals) Inner layer: cyclic polyolefin resin (ZEONOR 1020R (trade name, manufactured by Zeon Corporation), density: 1.01 g / cm ３ , melt flow rate (280 ° C, 21.18 N load): 20 g / 10 min, Izod impact strength: 60 J / m) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Intermediate layer: ethylene-vinyl alcohol copolymer resin (density: 1.19 g / cm ３ , melt flow rate (190 ° C, 21.18 N load): 1.6 g / 10 min, ethylene copolymerization ratio: 32 mol%) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３, Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Outer layer: High-density polyethylene resin (density: 0.951 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 0.18 g / 10 min) (Cap for multi-layer container made of resin for filling high-purity chemical liquids) Cap body: Linear low-density polyethylene resin (density: 0.938 g / cm ３ , melt flow rate (190°C, 21.18 N load): 3.8 g / 10 min) and packing: same as the inner layer resin of the container body. (Production of Container Body and Cap of Multilayer Container Made of Resin for Filling High-Purity Chemical Liquids) The container body of the multilayer container made of resin for filling high-purity chemical liquids was produced by molding a multilayered cylindrical parison using an extruder, sandwiching the extruded parison in a mold to form the desired container shape, and cooling it by blowing compressed air from a blow pin to produce a 500 mL container. The cap body and packing were produced by injection molding using a mold having a recess in the shape of the mold that would result in the desired shape. The cap body and packing were assembled to form a cap for a multilayer container made of resin for filling high-purity chemical liquids. The container body and cap were screwed together to form a multilayer container made of resin for filling high-purity chemical liquids, as shown in Figure 1.

[0058] Example 2 The following materials were used in the order of lamination for a multi-layer container made of resin for filling with high-purity liquid chemicals and having a cap. (Container body of multi-layer container made of resin for filling with high-purity liquid chemicals) Inner layer: cyclic polyolefin resin (ZEONOR 1420R (trade name, manufactured by Zeon Corporation), density: 1.01 g / cm ３ , melt flow rate (280 ° C, 21.18 N load): 20 g / 10 min, Izod impact strength: 32 J / m) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Intermediate layer: ethylene-vinyl alcohol copolymer resin (density: 1.19 g / cm ３ , melt flow rate (190 ° C, 21.18 N load): 1.6 g / 10 min, ethylene copolymerization ratio: 32 mol%) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３, Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Outer layer: High-density polyethylene resin (density: 0.951 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 0.18 g / 10 min) (Cap for multi-layer container made of resin for filling high-purity chemical liquids) Cap body: Linear low-density polyethylene resin (density: 0.938 g / cm ３ , melt flow rate (190°C, 21.18 N load): 3.8 g / 10 min) · Gasket: Same as the inner layer resin of the container body. (Preparation of Container Body and Cap of Multilayer Container Made of Resin for Filling High-Purity Chemical Liquids) The container body of the multilayer container made of resin for filling high-purity chemical liquids was prepared by molding a multilayered cylindrical parison using an extruder, sandwiching the extruded parison in a mold to form the desired container shape, and cooling it by blowing compressed air from a blow pin to produce a 500 mL container. The cap body and gasket were also prepared by injection molding using a mold having a recess in the shape of the mold that would result in the desired shape. The cap body and gasket were assembled to form a multilayer container cap made of resin for filling high-purity chemical liquids. The container body and cap were screwed together to form a multilayer container made of resin for filling high-purity chemical liquids, as shown in Figure 1. The container body and cap of the multilayer container made of resin for filling high-purity chemical liquids were prepared in the same manner as in Example 1, except for some differences in materials. The container body and the cap were screwed together to form a resin multi-layer container for filling with high-purity chemical solutions.

[0059] Comparative Example 1 The following materials were used in the order of lamination for a multi-layer container made of resin for filling with high-purity chemical liquids and having a cap: (Container body made of multi-layer container made of resin for filling with high-purity chemical liquids) Inner layer: cyclic polyolefin resin (ZEONOR 1020R (trade name, manufactured by Zeon Corporation), density: 1.01 g / cm ３ , melt flow rate (280 ° C, 21.18 N load): 20 g / 10 min, Izod impact strength: 60 J / m) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Intermediate layer: ethylene-vinyl alcohol copolymer resin (density: 1.19 g / cm ３, melt flow rate (190 ° C, 21.18 N load): 1.6 g / 10 min, ethylene copolymerization ratio: 32 mol%) Adhesive layer: maleic anhydride modified polyethylene resin (density: 0.915 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 1.4 g / 10 min) Outer layer: High-density polyethylene resin (density: 0.955 g / cm ３ , Melt flow rate (190 ° C, 21.18 N load): 2.3 g / 10 min) (cap for resin multilayer container for filling high-purity chemical liquids) Cap body: Linear low-density polyethylene resin (density: 0.938 g / cm ３ , melt flow rate (190°C, 21.18 N load): 3.8 g / 10 min) · Gasket: Same as the inner layer resin of the container body. (Production of Container Body and Cap of Multilayer Container Made of Resin for Filling High-Purity Chemical Liquids) The container body of the multilayer container made of resin for filling high-purity chemical liquids was produced by blow molding, in which a multilayered tubular parison was molded using an extruder, the extruded parison was sandwiched between a mold to form the desired container shape, and cooled by blowing compressed air from a blow pin. In addition, the cap body and gasket were produced by injection molding using a mold with a recess in the shape of the mold that would result in the desired shape. The cap body and gasket were assembled to form a cap for a multilayer container made of resin for filling high-purity chemical liquids. The container body and cap were then screwed together to form a multilayer container made of resin for filling high-purity chemical liquids, as shown in Figure 1.

[0060] As described above, multilayer containers made of resin for filling high-purity chemical solutions as described in Examples 1 and 2 and Comparative Example 1 were produced. As a result, containers could be molded in Examples 1 and 2, but in Comparative Example 1, a container could not be molded due to the occurrence of drawdown.

[0061] (Drop Evaluation Test) The containers of Examples 1 and 2, which were filled to the brim with water and stored at room temperature, and the containers filled to the brim with antifreeze and stored at -19°C or below, were dropped from a height of 1.2 m to check for breakage or leakage. As a result of the evaluation, no breakage or leakage occurred in Examples 1 and 2.

[0062] As is clear from the comparison between the Examples and Comparative Examples, the multilayer containers made of resin for filling high-purity chemical solutions in the Examples did not suffer from drawdown, and container molding was possible, and no breakage or leakage occurred in the drop evaluation test, whereas the multilayer containers in the Comparative Examples could not be molded into containers due to the occurrence of drawdown.

[0063] The resin multilayer container for filling high-purity chemical liquids to which the present invention is applied can be used for transporting and storing high-purity chemical liquids such as semiconductor manufacturing chemical liquids selected from photoresist liquids, cleaning liquids and etching liquids, eluents for liquid chromatography or liquid chromatography / MS for diagnostic equipment, and chemical liquids for analysis.

[0064] Reference numeral 1 denotes a resin multilayer container for filling with high-purity chemicals, 1a denotes the outer periphery, 10 denotes the container body, 11 denotes the inner layer, 11a denotes the extension layer, 12 denotes the adhesive layer, 13 denotes the intermediate layer, 14 denotes the adhesive layer, 15 denotes the outer layer, 17 denotes the opening, 18 denotes the mouth, 19 denotes the male screw, 20 denotes the inner cavity, 21 denotes the high-purity chemical, 30 denotes the cap, 31 denotes the packing, 31a denotes the packing base, 31b denotes the annular protrusion, 32 denotes the claw, 33 denotes the non-slip surface, and 39 denotes the female screw.

Claims

1. A resin multilayer container for filling the inner space with a high-purity chemical solution, comprising, in order from the inner space side to the outer periphery side, an inner layer made of cyclic polyolefin, an adhesive layer containing maleic anhydride-modified polyethylene, a barrier layer made of ethylene-vinyl alcohol copolymer, another adhesive layer containing maleic anhydride-modified polyethylene, and a density of 0.945 to 0.965 g / cm ３ a high-density polyethylene outer layer having a melt flow rate (190°C, 21.18N load) of 0.5 g / 10 min or less; and a high-density polyethylene outer layer having a melt flow rate (190°C, 21.18N load) of 0.5 g / 10 min or less, and the internal space has a volume of more than 100 mL and 4 L or less.

2. A resin multilayer container for filling high-purity chemical solutions according to claim 1, characterized in that the inner layer is made of a cyclic polyolefin having a melt flow rate (280°C, 21.18 N load) of 6 g / 10 min or more and 60 g / 10 min or less and / or an Izod impact strength in accordance with ASTM D256 of 18 J / m or more and 60 J / m or less.

3. A multi-layer container made of resin for filling with high-purity chemical liquids as described in claim 1, characterized in that the inner space has an opening for filling or discharging the high-purity chemical liquid, a cap that closes the opening is screwed on and / or inserted, and the inner top surface of the cap has a gasket made of the same type of cyclic polyolefin that closes the opening.

4. A multi-layer container made of resin for filling with high-purity chemical liquids as described in claim 3, characterized in that the upper end of the opening and the inner circumference connected to it are covered with a layer extending from the inner layer made of cyclic polyolefin.

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