Film, method for producing same, and container using said film

Abstract

The present invention provides a film for refrigerated storage, which is provided with at least one layer that contains an alicyclic structure-containing resin, wherein: the Charpy impact strength S(23) of the alicyclic structure-containing resin is 100 kJ / m2 or more as determined at 23°C after a specific EO sterilization treatment of the alicyclic structure-containing resin; and the Charpy impact strength S(-80) of the alicyclic structure-containing resin satisfies formula (1) as determined at -80°C after the specific EO sterilization treatment of the alicyclic structure-containing resin. The present invention also provides a method for producing the film. The present invention also provides a container which uses the film.　(1): S(-80) / S(23) ≥ 0.7

Description

Film, its manufacturing method, and container using said film

[0001] The present invention relates to a film suitable for frozen storage applications, a method for producing the same, and a container using the film.

[0002] Resin articles and packaging materials have been widely used for a long time, but they tend to have low impact strength in low-temperature environments, and methods for improving this have been studied (Patent Documents 1 to 5).

[0003] For example, Patent Documents 4 and 5 describe that a resin containing a polymer having an alicyclic structure, such as a norbornene-based polymer, exhibits good impact strength at low temperatures.

[0004] Japanese Patent No. 7342694 Japanese Patent No. 7159672 JP Patent Publication No. 2011-525558 (Corresponding Publication: US Patent Application Publication No. 2011 / 0105697) JP 2001-64525 A JP 2-253023 A

[0005] Resin films are sometimes used as containers for storing medicines and other drugs in a frozen state. Such containers are usually sterilized, at least inside the container. Ethylene oxide (EO) sterilization is widely used as the sterilization method. However, containers that have been sterilized with ethylene oxide (EO) may experience a significant decrease in impact strength in a low-temperature environment (a significant decrease in impact resistance at low temperatures). Hereinafter, ethylene oxide (EO) sterilization may be referred to as "EO sterilization."

[0006] The present invention has been made in view of the above-mentioned circumstances, and aims to provide a film for frozen storage that can have good impact strength in a low-temperature environment after EO sterilization, a container using the same, and a method for producing the film.

[0007] As a result of extensive investigations aimed at solving the above-mentioned problems, the present inventors have found that by using an alicyclic structure-containing resin and carrying out a step of drying the resin before molding into a film and a step of extruding the resin into a film in a low-oxygen atmosphere, it is possible to realize a film that can have good impact strength in a low-temperature environment after EO sterilization, and have completed the present invention.

[0008] <1> A film for frozen storage, comprising at least one layer containing an alicyclic structure-containing resin, wherein the alicyclic structure-containing resin has a Charpy impact strength S(23) of 100 kJ / m or less when measured at 23°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is brought into contact with ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours. ２ or more, and the Charpy impact strength S(-80) of the alicyclic structure-containing resin measured at -80°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is contacted with ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours satisfies the following formula (1): S(-80) / S(23)≧0.7 (1) <2> The film according to <1>, wherein the Charpy impact strength S(23) and the Charpy impact strength S(-80) satisfy the following formula (2): S(-80) / S(23)≧0.8 (2) <3> The film according to <1> or <2>, wherein the Charpy impact strength S(23) and the Charpy impact strength S(-194) of the alicyclic structure-containing resin measured at −194° C. after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50° C. and a relative humidity of 50% for 6 hours satisfy the following formula (3): S(-194) / S(23)≧0.25 (3) <4> The alicyclic structure-containing resin is a tricyclo[4.3.0.1 ２，５] The film according to any one of <1> to <3>, which contains a polymer having a deca-3,7-diene skeleton. <5> The film according to any one of <1> to <4>, which contains a first resin layer containing the alicyclic structure-containing resin and a second resin layer, and the second resin layer contains at least one resin selected from the group consisting of a hydrogenated styrene-based thermoplastic elastomer resin, a polyvinyl alcohol resin, an ethylene vinyl alcohol resin, a linear low-density polyethylene resin, and a polypropylene resin. <6> The film according to any one of <1> to <5>, in which the layer containing the alicyclic structure-containing resin in the film has been sterilized with ethylene oxide (EO). <7> The film according to any one of <1> to <6>, which has a total thickness of 10 μm or more and 350 μm or less, and a ratio of the thickness of the layer containing the alicyclic structure-containing resin to the total thickness of the film of 0.2 or more and 1.0 or less. <8> A container for frozen storage used to store a drug, the container comprising the film according to any one of <1> to <7>. <9> The container according to <8>, wherein a layer of the film containing the alicyclic structure-containing resin is disposed inside the container, and the layer containing the alicyclic structure-containing resin has been sterilized. <10> The container according to <8> or <9>, wherein the container has a bag shape. <11> The container according to any one of <8> to <10>, wherein the drug contains a biochemical material. <12> A film manufacturing method for manufacturing the film according to any one of <1> to <7>, comprising a step (1) of drying an alicyclic structure-containing resin and a step (2) of extruding the dried alicyclic structure-containing resin into a film, wherein the step (2) is carried out in an inert gas atmosphere or under reduced pressure.

[0009] According to the present invention, it is possible to provide a film for frozen storage that can have good impact strength in a low-temperature environment after EO sterilization, a container using the same, and a method for producing the film.

[0010] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and can be implemented with any modifications within the scope of the claims of the present invention and their equivalents. The components of the embodiments shown below can be combined as appropriate.

[0011] 1. Overview of the Film of the Invention A film according to one embodiment of the present invention is a film for frozen storage, and includes at least one layer containing an alicyclic structure-containing resin. This film has a Charpy impact strength S(23) of the alicyclic structure-containing resin measured at 23°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours, and the Charpy impact strength S(23) of the alicyclic structure-containing resin is equal to or greater than a predetermined value.

[0012] Furthermore, the Charpy impact strength S(23) of this film and the Charpy impact strength S(-80) of the alicyclic structure-containing resin measured at -80°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours satisfy the following formula (1): S(-80) / S(23)≧0.7 (1)

[0013] Hereinafter, the ethylene oxide (EO) sterilization treatment in which an alicyclic structure-containing resin is brought into contact with ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours before measuring the Charpy impact strength may be referred to as "EO sterilization treatment (A)." Furthermore, when simply referring to "EO sterilization treatment," this broadly means a treatment in which the resin is brought into contact with ethylene oxide gas, and treatment conditions such as temperature, relative humidity, and treatment time are not limited.

[0014] According to this embodiment, the film has a layer containing an alicyclic structure-containing resin having a specific Charpy impact strength, and thus the film can have good impact strength in a low-temperature environment after EO sterilization, making it suitable for frozen storage of items that require sterilization, such as medicines.

[0015] Here, EO sterilization allows for sterilization at low temperatures and low humidity, making it possible to treat materials that are sensitive to temperature and humidity. More specifically, EO sterilization is typically performed at temperatures of approximately 50°C to 60°C, making it possible to treat materials that are sensitive to heat. Furthermore, unlike steam sterilization, materials are not exposed to large amounts of moisture, making it possible to use EO sterilization on materials that are sensitive to moisture. Furthermore, EO sterilization is effective against all microorganisms. Furthermore, ethylene oxide gas has good permeability to materials to be sterilized. Specifically, ethylene oxide gas has good permeability to plastic films, paper, cloth, etc., making it possible to sterilize materials even in a packaged state. Furthermore, ethylene oxide gas is not corrosive to metals and other materials, making it possible to treat all materials.

[0016] As mentioned above, EO sterilization is a sterilization process that places less strain on non-sterilized items. However, containers made of films that have been sterilized with EO sterilization may experience a significant decrease in impact strength in low-temperature environments.

[0017] The present inventors have discovered that by using an alicyclic structure-containing resin, drying the resin before forming it into a film, and extruding the resin in a low-oxygen atmosphere to form a film, it is possible to obtain a film that has good impact strength in a low-temperature environment after EO sterilization. Although the mechanism behind this is unclear, the present inventors speculate as follows. However, the technical scope of the present invention is not limited to the mechanism described below.

[0018] Although conventional films containing alicyclic structure-containing resins tend to exhibit high impact strength in low-temperature environments, when subjected to EO sterilization, the impact strength in low-temperature environments may be significantly reduced. This is thought to be due to the occurrence of oxidative degradation of the alicyclic structure-containing resin contained in the film during film molding. It is thought that the deterioration of the resin in conventional films containing such oxidatively deteriorated resins is further accelerated by EO sterilization, resulting in a significant reduction in impact strength in low-temperature environments.

[0019] In contrast, by drying the alicyclic structure-containing resin before molding into a film, the amount of dissolved oxygen contained in the alicyclic structure-containing resin can be reduced, and by extruding the alicyclic structure-containing resin to mold into a film in a low-oxygen atmosphere, a film can be obtained in which deterioration of the alicyclic structure-containing resin is suppressed, and it is presumed that deterioration of the alicyclic structure-containing resin due to EO sterilization treatment can also be suppressed.

[0020] 2. Alicyclic Structure-Containing Resin The alicyclic structure-containing resin according to this embodiment includes an alicyclic structure-containing polymer. This alicyclic structure-containing resin also has a specific Charpy impact strength.

[0021] <2.1. Charpy Impact Strength> The film according to this embodiment has a Charpy impact strength S(23) of the alicyclic structure-containing resin measured at 23°C after an ethylene oxide (EO) sterilization treatment (A) in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours. ２ The Charpy impact strength S(23) is preferably 110 kJ / m or more. ２ More preferably, 120 kJ / m ２ The upper limit of the Charpy impact strength S(23) is preferably as high as possible, but is not particularly limited. For example, it may be 400 kJ / m ２ less than 350 kJ / m ２ or less, 300 kJ / m ２ This is because, by containing an alicyclic structure-containing resin having a Charpy impact strength S(23) of the above lower limit or more, the film can have good impact strength even after EO sterilization treatment.

[0022] Furthermore, in the film according to this embodiment, the Charpy impact strength S(23) described above and the Charpy impact strength S(-80) of the alicyclic structure-containing resin measured at -80°C after the EO sterilization treatment (A) usually satisfy the following formula (1): S(-80) / S(23)≧0.7 (1)

[0023] In this embodiment, it is preferable that the Charpy impact strength S(23) and the Charpy impact strength (−80) satisfy the following formula (2): S(−80) / S(23)≧0.8 (2)

[0024] The left sides of equations (1) and (2) represent the ratio of the Charpy impact strength S(-80) measured at -80°C after EO sterilization (A) to the Charpy impact strength S(23) measured at 23°C after EO sterilization (A). Satisfying equations (1) and (2) indicates that the decrease in impact strength in a low-temperature environment of about -80°C is suppressed compared to the impact strength in a normal temperature environment of about 23°C.

[0025] The ratio S(-80) / S(23) is usually 0.7 or more, preferably 0.8 or more, and more preferably 0.9 or more. The larger the ratio, the better, and the upper limit is not particularly limited, but is usually 2.0 or less, and can be 1.9 or less, or 1.8 or less. When the ratio S(-80) / S(23) is in the above range, the film can have excellent impact strength in a low-temperature environment even after EO sterilization.

[0026] In this embodiment, it is preferable that the Charpy impact strength S(23) and the Charpy impact strength S(-194) of the alicyclic structure-containing resin measured at -194°C after the EO sterilization treatment (A) satisfy the following formula (3): S(-194) / S(23)≧0.25 (3)

[0027] The left side of equation (3) represents the ratio of the Charpy impact strength S(-194) measured at -194°C after EO sterilization (A) to the Charpy impact strength S(23) measured at 23°C after EO sterilization (A). Satisfying equation (3) indicates that a significant decrease in impact strength is suppressed even in an extremely low temperature environment such as -194°C.

[0028] The ratio S(-194) / S(23) is usually 0.25 or more, preferably 0.3 or more, and more preferably 0.35 or more. The larger the ratio, the better. The upper limit is not particularly limited, but is usually 1.0 or less, and may be 0.8 or less, or 0.6 or less. By having the ratio S(-194) / S(23) within the above range, the film can exhibit good impact strength even after EO sterilization (A) and in an extremely low-temperature environment.

[0029] The relationship of the formulas (1) to (3) in this embodiment can be expressed by, for example, calculating the Charpy impact strength S(T) (kJ / m) of the alicyclic structure-containing resin measured at a temperature T (°C) after the EO sterilization treatment (A) of the alicyclic structure-containing resin under the above-described conditions. ２ ) It can also be considered that the Charpy impact strengths at T = 23 ° C., T = -80 ° C., and T = -194 ° C. can satisfy the relationship.

[0030] In this embodiment, the Charpy impact strength of the alicyclic structure-containing resin after the EO sterilization treatment (A) measured at a predetermined temperature can be measured by preparing a test piece (unnotched, length 80 mm × width 10 mm × thickness 4 mm) using the alicyclic structure-containing resin, subjecting it to the EO sterilization treatment (A), and then measuring it at a predetermined temperature in accordance with ISO 179-1. Measurements are performed on five test pieces, and the average value can be used as the Charpy impact strength.

[0031] EO sterilization treatment (A) is carried out by ethylene oxide (EO) sterilization, in which the test specimens are exposed to an ethylene oxide gas atmosphere (ethylene oxide gas concentration 30 wt%) at a temperature of 50°C and a relative humidity of 50% for 6 hours. A mixed gas of ethylene oxide gas and carbon dioxide gas is used as the treatment gas. The ethylene oxide gas concentration (wt%) mentioned above represents the weight percentage of ethylene oxide gas in a 100 wt% mixed gas of ethylene oxide gas and carbon dioxide gas. EO sterilization treatment (A) can be carried out using a known EO sterilization device (for example, an EO gas sterilizer (Steri-Bag EO Gas Sterilizer) manufactured by 3M).

[0032] In the EO sterilization process (A), a pretreatment step is usually performed by leaving the container standing for 13 hours in an environment at a temperature of 50°C and a relative humidity of 50%. Furthermore, in the EO sterilization process (A), a posttreatment step is performed by aeration for 24 hours to remove the toxicity of ethylene oxide gas. Aeration can be performed in a closed space in an environment at a temperature of 50°C and a relative humidity of 50%.

[0033] 2.2. Resin Composition The film according to this embodiment contains an alicyclic structure-containing resin. The alicyclic structure-containing resin contains at least an alicyclic structure-containing polymer and, if necessary, further contains any optional component. The alicyclic structure-containing resin is usually a thermoplastic resin.

[0034] (Polymer containing an alicyclic structure) The polymer containing an alicyclic structure is a polymer having an alicyclic structure in the repeating unit of the polymer, and may be either a polymer having an alicyclic structure in the main chain or a polymer having an alicyclic structure in the side chain. Among them, from the viewpoint of the mechanical strength, heat resistance, etc. of the obtained resin film, a polymer containing an alicyclic structure in the main chain is preferred.

[0035] Examples of the alicyclic structure include saturated alicyclic hydrocarbon (cycloalkane) structures, unsaturated alicyclic hydrocarbon (cycloalkene, cycloalkyne) structures, etc. Among these, from the viewpoints of mechanical strength, heat resistance, etc., cycloalkane structures and cycloalkene structures are preferred, and cycloalkane structures are particularly preferred.

[0036] The number of carbon atoms constituting the alicyclic structure is preferably 4 or more, more preferably 5 or more, per one alicyclic structure, and is preferably 30 or less, more preferably 20 or less, particularly preferably 15 or less, whereby mechanical strength, heat resistance, and film formability are well balanced, which is suitable.

[0037] The proportion of repeating units having an alicyclic structure in the alicyclic structure-containing polymer can be appropriately selected depending on the intended use, but is preferably 55% by weight or more, more preferably 70% by weight or more, and particularly preferably 90% by weight or more. When the proportion of repeating units having an alicyclic structure in the alicyclic structure-containing polymer is within this range, it is preferable from the viewpoint of the transparency and heat resistance of the film.

[0038] Examples of the alicyclic structure-containing polymer include a copolymer of a cyclic olefin and a chain olefin. The copolymer of a cyclic olefin and a chain olefin is usually a polymer obtained by addition copolymerization of the cyclic olefin and the chain olefin.

[0039] Specific examples of the cyclic olefin include monocyclic olefins such as cyclopentene, cyclohexene, cyclooctene, cyclopentadiene, and 1,3-cyclohexadiene;

[0040] Bicyclo[2.2.1]hept-2-ene (trivial name: norbornene), 5-methyl-bicyclo[2.2.1]hept-2-ene, 5,5-dimethyl-bicyclo[2.2.1]hept-2-ene, 5-ethyl-bicyclo[2.2.1]hept-2-ene, 5-butyl-bicyclo[2.2.1]hept-2-ene, 5-ethylidene-bicyclo[2.2.1]hept-2-ene, 5-hexyl bicyclic olefins such as ru-bicyclo[2.2.1]hept-2-ene, 5-octyl-bicyclo[2.2.1]hept-2-ene, 5-octadecyl-bicyclo[2.2.1]hept-2-ene, 5-methylidene-bicyclo[2.2.1]hept-2-ene, 5-vinyl-bicyclo[2.2.1]hept-2-ene, and 5-propenyl-bicyclo[2.2.1]hept-2-ene;

[0041] Tricyclo[4.3.0.1 ２，５ ]deca-3,7-diene (tricyclo[5.2.1.0 ２，６ ]deca-3,8-diene) (trivial name: dicyclopentadiene), tricyclo[5.2.1.0 ２，６ ]dec-3-ene, tricyclo[6.2.1.0 ２，７ ]undeca-3,9-diene, tricyclo[6.2.1.0 ２，７]undeca-4,9-diene, tricyclo[6.2.1.0 ２，７ ]undec-9-ene, 5-cyclopentyl-bicyclo[2.2.1]hept-2-ene, 5-cyclohexyl-bicyclo[2.2.1]hept-2-ene, 5-cyclohexenylbicyclo[2.2.1]hept-2-ene, 5-phenyl-bicyclo[2.2.1]hept-2-ene and other three-ring cyclic olefins;

[0042] Tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene (also simply referred to as "tetracyclododecene"), 9-methyltetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-ethyltetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-methylidenetetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-ethylidenetetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-vinyltetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-propenyl-tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, tetracyclo[9.2.1.0 ２,１０ .0 ３,８ ]tetradeca-3,5,7,12-tetraene (also called 1,4-methano-1,4,4a,9a-tetrahydrofluorene), tetracyclo[10.2.1.0 ２，１１ .0 ４，９ ] tetracyclic olefins such as pentadeca-4,6,8,13-tetraene (also known as 1,4-methano-1,4,4a,9,9a,10-hexahydroanthracene);

[0043] 9-Cyclopentyl-tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-cyclohexyl-tetracyclo[6.2.1.1 ３，６ .0 ２，７] dodec-4-ene, 9-cyclohexenyl-tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, pentacyclo[6.6.1.1 ３，６ .0 ２，７ .0 ９，１４ ]-4-hexadecene, pentacyclo[6.5.1.1 ３，６ .0 ２，７ .0 ９，１３ ]-4-pentadecene, pentacyclo[7.4.0.0 ２，７ .1 ３，６ .1 １０，１３ ]-4-pentadecene, 9-phenyl-cyclopentyl-tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, heptacyclo[8.7.0.1 ２，９ .1 ４，７ .1 １１，１７ .0 ３，８ .0 １２，１６ ]-5-eicosene, heptacyclo[8.7.0.1 ２，９ .0 ３，８ .1 ４，７ .0 １２，１７ .1 １３，ｌ６ ]-14-eicosene, etc. These cyclic olefins may be used either alone or in combination of two or more.

[0044] Specific examples of the chain olefin are not particularly limited as long as it is copolymerizable with the above-mentioned cyclic olefin, and include, for example, linear or branched olefins having 2 to 20 carbon atoms, such as ethylene, propylene, butene, pentene, hexene, butadiene, pentadiene, and hexadiene.

[0045] The alicyclic structure-containing polymer may also be the above-mentioned ring-opening polymer of a cyclic olefin, or a hydrogenated product of the ring-opening polymer of a cyclic olefin.

[0046] Furthermore, examples of the alicyclic structure-containing polymer include norbornene polymers, monocyclic olefin polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and hydrogenated versions thereof. Among these, norbornene polymers are preferably used because of their good transparency and moldability.

[0047] Examples of norbornene-based polymers include ring-opening polymers of monomers having a norbornene structure, ring-opening copolymers of monomers having a norbornene structure and other monomers, or hydrogenated products thereof; addition polymers of monomers having a norbornene structure, addition copolymers of monomers having a norbornene structure and other monomers, or hydrogenated products thereof; and the like. Among these, hydrogenated ring-opening (co)polymers of monomers having a norbornene structure are particularly suitable for use from the viewpoints of transparency, moldability, heat resistance, low moisture absorption, dimensional stability, light weight, etc. "(Co)polymer" refers to polymers and copolymers.

[0048] Examples of the monomer having a norbornene structure include bicyclo[2.2.1]hept-2-ene (common name: norbornene), tricyclo[4.3.0.1]hept-2-ene, and the like. ２，５ ]deca-3,7-diene (common name: dicyclopentadiene), 7,8-benzotricyclo[4.3.0.1 ２，５ ]dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo[4.4.0.1 ２，５ .1 ７，１０ ]dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds (for example, those having a substituent on the ring). Examples of the substituent include an alkyl group, an alkylene group, and a polar group. Furthermore, a plurality of these substituents, which may be the same or different, may be bonded to the ring.

[0049] Examples of the polar group include a heteroatom or an atomic group having a heteroatom. Examples of the heteroatom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfonic acid group.

[0050] Examples of the substituted monomer include 8-ethylidene-tetracyclo[4.4.0.1 ２，５ .1 ７，１０ ]-dodec-3-ene (trivial name: ethylidenetetracyclododecene).

[0051] The monomer having a norbornene structure may be used alone or in combination of two or more kinds in any ratio.

[0052] As the norbornene polymer, a monomer having a norbornene structure such as tricyclo[4.3.0.1 ２，５ ] deca-3,7-diene (dicyclopentadiene). Such polymers are usually polymers using tricyclo[4.3.0.1 ２，５ ] contains a deca-3,7-diene skeleton (dicyclopentadiene skeleton). When the alicyclic structure-containing resin contains a polymer containing a dicyclopentadiene skeleton, it can be made into a film that can have high impact strength in a low-temperature environment after EO sterilization treatment.

[0053] The proportion of dicyclopentadiene monomer contained therein, relative to the total amount (100% by weight) of monomers used as raw materials for the norbornene polymer, is preferably 10% by weight or more, more preferably 20% by weight or more, even more preferably 30% by weight or more, and is preferably 95% by weight or less, more preferably 90% by weight or less, even more preferably 85% by weight or less. When the proportion of dicyclopentadiene monomer is within the above range, a film that can have high impact strength in a low-temperature environment after EO sterilization can be obtained.

[0054] Usually, the ratio of a repeating unit (monomer unit) derived from a certain monomer in a norbornene-based polymer is equal to the ratio (polymerization ratio) of that monomer in all the monomers. Therefore, usually, the ratio of a dicyclopentadiene skeleton in a norbornene-based polymer is equal to the polymerization ratio of the dicyclopentadiene monomer to the total amount of the monomers. Therefore, the ratio of the dicyclopentadiene skeleton to 100% by weight of the norbornene-based polymer is preferably within the same range as the polymerization ratio of the dicyclopentadiene monomer.

[0055] In addition, when the norbornene-based polymer is a polymer using a dicyclopentadiene monomer as a monomer having a norbornene structure, it is preferable that the norbornene-based polymer further contains a tetracyclo[4.4.0.1 ２，５ .1 ７，１０ Preferably, the norbornene-based polymer is a polymer using at least one of a tetracyclododecene monomer and a bicyclo[2.2.1]hept-2-ene (norbornene) monomer, and more preferably a polymer using both a tetracyclododecene monomer and a norbornene monomer. In particular, when the norbornene-based polymer is a polymer using a dicyclopentadiene monomer, a tetracyclododecene monomer, and a norbornene monomer, it can be a film that can effectively increase impact strength in a low-temperature environment after EO sterilization.

[0056] The ratio of the tetracyclododecene monomer to 100 parts by weight of the dicyclopentadiene monomer as a raw material for the norbornene polymer is usually 70 parts by weight or more, preferably 80 parts by weight or more, more preferably 90 parts by weight or more, and usually 130 parts by weight or less, preferably 120 parts by weight or less, more preferably 110 parts by weight or less. Furthermore, the ratio of the norbornene monomer to 100 parts by weight of the dicyclopentadiene monomer as a raw material for the norbornene polymer is usually 70 parts by weight or more, preferably 80 parts by weight or more, more preferably 90 parts by weight or more, and usually 130 parts by weight or less, preferably 120 parts by weight or less, more preferably 110 parts by weight or less. The ratio of the tetracyclododecene monomer and the ratio of the norbornene monomer within the above ranges enables the production of a film that can effectively increase impact strength in a low-temperature environment after EO sterilization.

[0057] In general, the ratio of tetracyclododecene skeletons to 100 parts by weight of dicyclopentadiene skeletons and the ratio of norbornene skeletons to 100 parts by weight of dicyclopentadiene skeletons in a norbornene-based polymer are identical to the ratio of tetracyclododecene monomers to 100 parts by weight of dicyclopentadiene monomers and the ratio of norbornene monomers to 100 parts by weight of dicyclopentadiene monomers in a norbornene-based polymer.

[0058] Examples of other monomers capable of ring-opening copolymerization with the monomer having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene, and derivatives thereof; cyclic conjugated dienes such as cyclohexadiene and cycloheptadiene, and derivatives thereof; etc. The other monomers capable of ring-opening copolymerization with the monomer having a norbornene structure may be used alone or in combination of two or more at any ratio.

[0059] A ring-opening polymer of a monomer having a norbornene structure and a ring-opening copolymer of a monomer having a norbornene structure and another monomer copolymerizable with the monomer can be obtained, for example, by polymerizing or copolymerizing the monomer in the presence of a known ring-opening polymerization catalyst.

[0060] Examples of other monomers that can be addition-copolymerized with the monomer having a norbornene structure include α-olefins having 2 to 20 carbon atoms, such as ethylene, propylene, 1-butene, pentene, hexene, butadiene, pentadiene, and hexadiene, and derivatives thereof; cycloolefins, such as cyclobutene, cyclopentene, and cyclohexene, and derivatives thereof; and non-conjugated dienes, such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, and 5-methyl-1,4-hexadiene. Among these, α-olefins are preferred, and ethylene is more preferred. The other monomers that can be addition-copolymerized with the monomer having a norbornene structure may be used alone, or two or more may be used in combination at any ratio.

[0061] An addition polymer of a monomer having a norbornene structure and an addition copolymer of a monomer having a norbornene structure and another monomer copolymerizable with the monomer can be obtained, for example, by polymerizing or copolymerizing the monomer in the presence of a known addition polymerization catalyst.

[0062] Examples of the monocyclic olefin polymer include addition polymers of cyclic olefin monomers having a single ring, such as cyclohexene, cycloheptene, and cyclooctene.

[0063] Examples of the cyclic conjugated diene polymer include polymers obtained by cyclization reaction of addition polymers of conjugated diene monomers such as 1,3-butadiene, isoprene, and chloroprene; 1,2- or 1,4-addition polymers of cyclic conjugated diene monomers such as cyclopentadiene and cyclohexadiene; and hydrogenated products thereof.

[0064] Examples of vinyl alicyclic hydrocarbon polymers include polymers of vinyl alicyclic hydrocarbon monomers such as vinylcyclohexene and vinylcyclohexane, and hydrogenated products thereof; hydrogenated products obtained by hydrogenating the aromatic ring moiety contained in polymers obtained by polymerizing vinyl aromatic hydrocarbon monomers such as styrene and α-methylstyrene; hydrogenated products of the aromatic ring of vinyl alicyclic hydrocarbon monomers, or copolymers such as random copolymers or block copolymers of vinyl aromatic hydrocarbon monomers with other monomers copolymerizable with these vinyl aromatic hydrocarbon monomers; etc. Examples of the block copolymers include diblock copolymers, triblock copolymers, or higher multiblock copolymers, as well as gradient block copolymers.

[0065] The weight-average molecular weight (Mw) of the alicyclic structure-containing polymer is usually 10,000 or more, preferably 15,000 or more, more preferably 20,000 or more, and usually 100,000 or less, preferably 80,000 or less, more preferably 50,000 or less. When the weight-average molecular weight is in this range, the mechanical strength and moldability of the film are well balanced, which is preferable.

[0066] The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the alicyclic structure-containing polymer is usually 1.2 or more, preferably 1.5 or more, more preferably 1.8 or more, and usually 3.5 or less, preferably 3.0 or less, more preferably 2.7 or less. When the molecular weight distribution is at least the lower limit of the above range, the productivity of the alicyclic structure-containing polymer can be increased and the production cost can be reduced. On the other hand, when it is at most the upper limit, the amount of low molecular weight components is reduced, and the stability of the layer containing the alicyclic structure-containing polymer can be improved.

[0067] The weight-average molecular weight Mw and number-average molecular weight Mn of the alicyclic structure-containing polymer can be measured in polyisoprene equivalent values ​​by gel permeation chromatography (hereinafter abbreviated as "GPC") using cyclohexane as a solvent. If the resin is insoluble in cyclohexane, they can be measured in polystyrene equivalent values ​​by GPC using toluene as a solvent.

[0068] The glass transition temperature of the alicyclic structure-containing polymer is not particularly limited, but is, for example, 40°C or higher, preferably 50°C or higher, more preferably 60°C or higher, and preferably 180°C or lower, more preferably 170°C or lower, and even more preferably 165°C or lower. Having the glass transition temperature of the alicyclic structure-containing polymer within the above range makes it easier to process the film into a container shape such as a bag. The glass transition temperature of the alicyclic structure-containing polymer can be measured by differential scanning calorimetry in accordance with JIS K7121. This measurement can be performed by raising the temperature of a sample from room temperature to 200°C at 20°C / min, then cooling to 40°C at 20°C / min, and then raising the temperature from 40°C to 200°C at 10°C / min.

[0069] (Proportion of Alicyclic Structure-Containing Polymer and Optional Components) The proportion of the alicyclic structure-containing polymer in the alicyclic structure-containing resin is usually 50% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more, and even more preferably 90% by weight or more, and is usually 100% by weight or less, and can be 99% by weight or less, or can be 95% by weight or less.

[0070] The alicyclic structure-containing resin may further contain an optional component in addition to the alicyclic structure-containing polymer.

[0071] (Antioxidant) Examples of optional components include antioxidants. Examples of the antioxidants that can be used include primary antioxidants such as hindered phenol-based antioxidants and amine-based antioxidants, and secondary antioxidants such as phosphorus-based antioxidants and sulfur-based antioxidants.

[0072] Specific examples of hindered phenol antioxidants include pentaerythritol-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}2,4,8,10-tetraoxaspiro[5,5]undecane, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] ... 2,6-di-t-butyl-4-ethylphenol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-di-t-butyl-4-hydroxyphenyl)propionate, thiodiethylene glycol bis[(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 4,4'-thiobis(6-t-butyl-m- cresol), 2,2'-methylenebis(4-methyl-6-t-butyl-6-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), bis[3,3-bis(4-hydroxy-3-t-butylphenyl)butylic acid]glycol ester, 4,4'-butylidenebis(6-t-butyl-m-cresol), 2,2'-ethylidenebis(4,6-di-t-butylphenol), 2,2'-ethylidenebis(4-s-butyl-6-t-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy- 5-t-butylphenyl)butane, bis[2-t-butyl-4-methyl-6-(2-hydroxy-3-t-butyl-5-methylbenzyl)phenyl]terephthalate, 1,3,5-tris(2,6-dimethyl-3-hydroxy-4-t-butylbenzyl)isocyanurate, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3,5-tris[(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate, tetrakis[methylene-3-(3,alkyl-substituted hindered phenol-based antioxidants such as 3,5-di-t-butyl-4-hydroxyanisole; alkoxy-substituted hindered phenol-based antioxidants such as 3,5-di-t-butyl-4-hydroxyanisole; and triazine group-containing hindered phenol-based antioxidants such as 6-(4-hydroxy-3,5-di-t-butylanilino)-2,4-bisoctylthio-1,3,5-triazine, 4-bisoctylthio-1,3,5-triazine, and 2-octylthio-4,6-bis-(3,5-di-t-butyl-4-oxyanilino)-1,3,5-triazine.

[0073] Specific examples of the amine-based antioxidant include 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 1-hydroxy-2,2,6,6-tetramethylpiperidinol, 2,2,6,6-tetramethyl-4-piperidyl benzoate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(2,2,6,6 bis(1,2,2,6,6-pentamethyl-4-piperidyl)di(tridecyl)-1,2,3,4-butanetetracarboxylate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)di(tridecyl)-1,2,3,4-butanetetracarboxylate, 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane / dibromoethane polycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane / 2,4-dichloro-6-morpholino-s-triazine polycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(2,2,6,6-tetramethyl-4-piperidyl)amino)-s-triazin-6-yl]-1, Examples include hindered amine compounds such as 5,8,12-tetraazadodecane and 1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino)-s-triazin-6-yl]-1,5,8,12-tetraazadodecane; and dialkylhydroxylamine compounds such as diethylhydroxylamine, dioctylhydroxylamine, didodecylhydroxylamine, and dioctadecylhydroxylamine.

[0074] Specific examples of phosphorus-based antioxidants include bis-(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, tris(2,4-di-t-butylphenyl phosphite), tetrakis(2,4-di-t-butyl-5-methylphenyl)-4,4'-biphenylene diphosphonite, bis-(2,6-dicumylphenyl)pentaerythritol diphosphite, 2,2-methylenebis(4,6-di-t-butylphenyl)octyl phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-t-butyl-4-methoxycarbonylethyl-phenyl)pentaerythritol diphosphite, and bis(2,6-di-t-butyl-4-octadecyloxycarbonylethyl-phenyl)pentaerythritol diphosphite.

[0075] Specific examples of sulfur-based antioxidants include dilauryl 3,3-thiodipropionate, dimyristyl 3,3'-thiodipropionate, distearyl 3,3-thiodipropionate, laurylstearyl 3,3-thiodipropionate, pentaerythritol-tetrakis-(β-lauryl-thio-propionate), 3,9-bis(2-dodecylthioethyl)-2,4,8,10-tetraoxaspiro[5,5]undecane, and the like.

[0076] When the film according to this embodiment is brought into contact with a biochemical sample, from the viewpoint of effectively suppressing adsorption of the biochemical substance at the contact portion, it is preferable to use a hindered phenol-based antioxidant as the antioxidant, and among these, it is more preferable to use pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate].

[0077] The above-mentioned antioxidants can be used alone or in combination of two or more.

[0078] The content of the antioxidant in the alicyclic structure-containing resin is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and even more preferably 0.09 parts by mass or more, and is preferably 0.7 parts by mass or less, more preferably 0.6 parts by mass or less, and even more preferably 0.5 parts by mass or less, relative to 100 parts by mass of the alicyclic structure-containing polymer. If the content of the antioxidant is within the above range relative to 100 parts by mass of the alicyclic structure-containing polymer, for example, when the film according to this embodiment is brought into contact with a biochemical substance sample, adsorption of the biochemical substance at the contact surface can be effectively suppressed.

[0079] (Other Components) In addition to the above-mentioned alicyclic structure-containing polymer and antioxidant, the alicyclic structure-containing resin may contain any component within the range that can obtain desired effects.Specifically, such optional components include the additives that can be used when preparing cyclic olefin polymers, such as chain transfer agents, polymerization regulators, polymerization reaction retarders, and reactive fluidizing agents; polymers other than the alicyclic structure-containing polymer, such as rubber polymers and thermoplastic elastomers; organic or inorganic fillers; inorganic fine particles; resin additives such as flame retardants, ultraviolet absorbers, weather stabilizers, antistatic agents, slip agents, metal soaps, antifogging agents, and plasticizers; oils such as natural oils and synthetic oils; release agents; fluorescent brighteners; dyes; pigments; colorants; antibacterial agents; deodorants; deodorizers. As the optional component, a commonly used compound, for example, a compound described in JP-A-2009-242568, a compound described in JP-A-2010-100683, a compound described in Japanese Patent No. 5613981, or the like can be used.

[0080] <3. Film Form> The form of the film according to the present embodiment is not particularly limited as long as it includes at least one layer containing an alicyclic structure-containing resin. For example, the film may have a single-layer structure including a layer containing an alicyclic structure-containing resin, or a multilayer structure including at least a first resin layer including an alicyclic structure-containing resin and a second resin layer including a resin other than the alicyclic structure-containing resin.

[0081] Examples of resins that can be contained in the second resin layer include hydrogenated styrene-based thermoplastic elastomer resins, polyvinyl alcohol resins, ethylene-vinyl alcohol resins, linear low-density polyethylene resins, and polypropylene resins. Examples of hydrogenated styrene-based thermoplastic elastomer resins include aromatic vinyl-conjugated diene block copolymers and block copolymers comprising an aromatic vinyl compound-based polymer block and an isobutylene-based polymer block, as described in International Publication No. 2014 / 087935.

[0082] When the film has a multilayer structure, the number of resin layers constituting the film is not particularly limited, but can be about 2 to 10 layers, preferably 2 to 5 layers. Furthermore, when the film has a multilayer structure, it is usually preferable that the first resin layer containing the alicyclic structure-containing resin is provided on one of the outermost surfaces of the multilayer film. Since the alicyclic structure-containing resin has low adsorption properties for biochemical substances contained in, for example, drugs, by providing the first resin layer of the film on the outermost surface, when the film is processed into a container, the first resin layer can be disposed inside the container, and a container that is less likely to adsorb biochemical substances can be obtained inside.

[0083] The total thickness of the film is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more, and is preferably 350 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less. By having the total thickness of the film in the above range, the film can effectively exhibit impact resistance and good moldability in a low-temperature environment.

[0084] The ratio of the thickness of the layer containing the alicyclic structure-containing resin to the total thickness of the film is usually 0.2 or more, preferably 0.3 or more, more preferably 0.4 or more. The ratio is usually 1.0 or less, and may be 0.9 or less, or may be 0.8 or less. When the thickness of the layer containing the alicyclic structure-containing resin to the total thickness of the film is in the above range, the film can effectively exhibit impact resistance in a low-temperature environment.

[0085] The total thickness of the film can be measured using a microprofile measuring device, a spectroscopic film thickness measuring device, etc. When the film is a multilayer film, the thickness of each layer can be measured, for example, by cutting the film with a microtome and observing the cross section with an optical microscope.

[0086] As described above, the film according to this embodiment can have good impact strength in a low-temperature environment after EO sterilization. The film itself may or may not be subjected to EO sterilization, with the former being more preferred.

[0087] When the film is subjected to EO sterilization, the EO sterilization is usually performed on at least one surface of the film if the film has a single layer structure, or on at least the surface of the film facing the first resin layer if the film has a multilayer structure.

[0088] The conditions for the EO sterilization treatment of the film are selected appropriately depending on the form and application of the film, but are typically carried out at a temperature within ±10°C of the temperature and relative humidity within ±10% of those used in the above-mentioned EO sterilization treatment (A), and for a time within ±2 hours of the treatment time in the EO sterilization treatment (A). Furthermore, from the standpoint of ease of handling, the EO sterilization treatment typically uses a mixed gas of ethylene oxide gas and carbon dioxide gas, and the ethylene oxide gas concentration in the mixed gas is typically 10% to 30% by weight. For example, a medical sterilizing gas (weight composition: ethylene oxide gas / carbon dioxide gas = 30 / 70) can also be used as the mixed gas.

[0089] In addition, before the EO treatment of the film, a pretreatment may be performed in which the film is left to stand for 6 to 15 hours in an environment at a temperature of 50°C ± 10°C and a relative humidity of 50% ± 10%. Furthermore, after the EO treatment, aeration may be performed for 12 to 24 hours to remove the toxicity of ethylene oxide gas. Aeration may be performed in a closed space at the same temperature and relative humidity as the pretreatment.

[0090] The film according to the present embodiment may also be subjected to a sterilization treatment other than EO sterilization, such as gamma ray sterilization, electron beam sterilization, or steam sterilization.

[0091] The film according to the present embodiment may be either sheet-like or long, but the latter is more preferable, because, for example, bag-shaped containers can be mass-produced by heat welding long films together, and therefore the film can provide containers with high production efficiency.

[0092] A "long" film refers to a film having a length that is 5 times or more its width, preferably 10 times or more its width, and specifically refers to a film having a length that can be wound into a roll for storage or transportation. There is no particular upper limit to the length, but it is usually 100,000 times or less its width.

[0093] 4. Uses of the Film The film according to this embodiment can generally be used for frozen storage. More specifically, the film according to this embodiment can generally be used as a material for containers for frozen storage. Here, "frozen storage" refers to storing a substance or a liquid in which a substance is dispersed or dissolved in a frozen (solidified) state, and generally refers to storage at or below the freezing point of the substance or the liquid.

[0094] The temperature at which the film is used for frozen storage is appropriately selected depending on the freezing temperature of the object to be stored, but the temperature of the environment in which the film is used during frozen storage (freezing temperature) is usually −20° C. or lower, preferably −40° C. or lower, more preferably −60° C. or lower, and particularly preferably −80° C. or lower, and usually −200° C. or higher, preferably −198° C. or higher, and more preferably −195° C. or higher. The film according to this embodiment contains an alicyclic structure-containing resin having a specific Charpy impact strength, and therefore can have good impact strength even in an extremely low-temperature usage environment.

[0095] Furthermore, since the film according to the present embodiment can suppress a decrease in impact strength in a low-temperature environment even by EO sterilization, it is preferably used in applications requiring sterilization, particularly applications requiring EO sterilization. Specifically, it is preferably used for the frozen storage of medicines and foods, and is particularly preferably used for the frozen storage of medicines.

[0096] 5. Film Manufacturing Method The above-described film can be manufactured using any manufacturing method, but a preferred manufacturing method includes the following steps (1) and (2). Hereinafter, this manufacturing method will be described as a film manufacturing method according to one embodiment of the present invention.

[0097] Step (1): A step of drying the alicyclic structure-containing resin. Step (2): A step of forming the dried alicyclic structure-containing resin into a film by extrusion in a low-oxygen atmosphere.

[0098] According to the film production method of this embodiment, by including steps (1) and (2), it is possible to produce a film that has good impact strength in a low-temperature environment after EO sterilization treatment.

[0099] <5.1. Step (1): Step of drying the alicyclic structure-containing resin> Step (1) is a step of drying the alicyclic structure-containing resin. In step (1), it is usually preferable to dry the resin processed into pellets. The shape of the pellets is not particularly limited, and may be a known shape such as a cylindrical shape, an elliptical cylindrical shape, or a rectangular pillar (square shape).

[0100] The drying temperature for the alicyclic structure-containing resin is usually lower than the glass transition temperature Tg of the alicyclic structure-containing resin, preferably (Tg - 10°C) or lower, more preferably (Tg - 15°C) or lower, and usually (Tg - 40°C) or higher, preferably (Tg - 30°C) or higher, more preferably (Tg - 20°C) or higher. By keeping the drying temperature within the above range, a film with good impact strength in a low-temperature environment can be obtained. Furthermore, heat fusion between pellets can be suppressed, making the pellets easier to handle. The glass transition temperature Tg of the alicyclic structure-containing resin can be measured by the same method as that for the glass transition temperature of the alicyclic structure-containing polymer described above.

[0101] The drying time of the resin is preferably 0.5 hours or more, more preferably 1 hour or more, even more preferably 1.5 hours or more, and preferably 4 hours or less, more preferably 3.5 hours or less, even more preferably 3 hours or less. By keeping the drying temperature within the above range, a film with good impact strength in a low-temperature environment can be obtained. In addition, heat fusion between pellets can be suppressed, making the pellets easier to handle.

[0102] The drying treatment in step (1) may be, for example, vacuum drying treatment, reduced pressure drying treatment in an air or nitrogen atmosphere, or normal pressure drying in an air or nitrogen atmosphere.

[0103] <5.2. Step (2): Step of Forming Film in Low-Oxygen Atmosphere> Step (2) is a step of forming the dried alicyclic structure-containing resin into a film by extrusion in a low-oxygen atmosphere.

[0104] In step (2), a film is formed by extrusion in a low-oxygen atmosphere, which can be specifically achieved by an inert gas atmosphere or reduced pressure.

[0105] The inert gas atmosphere can be achieved, for example, by replacing the air in the molding apparatus with an inert gas. Examples of inert gases include argon gas, nitrogen gas, helium gas, krypton gas, and xenon gas, with nitrogen gas being preferred due to its ease of availability. One method for replacing the air in the molding apparatus with an inert gas is to blow an inert gas into a hopper for supplying raw materials.

[0106] When an inert gas is used, the oxygen concentration in the atmosphere inside the molding apparatus is usually 1000 ppm or less, preferably 900 ppm or less, more preferably 800 ppm or less, and is usually 100 ppm or more, for example, 200 ppm or more, for example, 300 ppm or more. The unit "ppm" is based on mass.

[0107] Alternatively, the reduced pressure can be achieved by, for example, reducing the pressure inside the molding apparatus. Specifically, the reduced pressure can be achieved by using a vacuum hopper to reduce the pressure inside the molding apparatus. The degree of vacuum inside the vacuum hopper can be, for example, 5 kPa or less, preferably 3 kPa or less, and more preferably 2 kPa or less. The lower limit of the degree of vacuum is not particularly limited, but can be, for example, 0.05 kPa or more, preferably 0.1 kPa or more.

[0108] The conditions for forming a film by extrusion are not particularly limited as long as the desired film can be obtained.For example, the cylinder temperature (molten resin temperature) is usually set higher than the glass transition temperature Tg of the alicyclic structure-containing resin, preferably (Tg + 100 ° C) or higher, more preferably (Tg + 110 ° C) or higher, even more preferably (Tg + 120 ° C) or higher, and usually (Tg + 150 ° C) or lower, more preferably (Tg + 140 ° C) or lower, even more preferably (Tg + 130 ° C) or lower.By setting the cylinder temperature within the above range, the alicyclic structure-containing resin can be efficiently formed into a film.

[0109] When the film has a multilayer structure, the film can be produced by co-extruding the alicyclic structure-containing resin and a resin other than the alicyclic structure-containing resin.

[0110] 6. Container A container according to one embodiment of the present invention is a container for cryopreservation used for storing medicines, and includes the film described above.

[0111] According to this embodiment, the container is provided with a film that can maintain good impact strength in a low-temperature environment even after EO sterilization, and therefore can be used to store medicines frozen in a good condition.

[0112] The shape of the container according to the present invention may be such that at least a portion thereof is provided with the above-described film, but is preferably a bag-like shape. When the container is bag-like, the structure of the bag can be a known bag structure using a film. Specific examples include, but are not limited to, a bag shape in which a single film is folded and sealed at the periphery, or a bag shape in which two films are overlapped and sealed at the periphery. Furthermore, when the container is bag-like, it may have a zipper, a cap, or the like.

[0113] In the container according to the present invention, it is preferable that a layer containing an alicyclic structure-containing resin of the film is disposed on the inside thereof, and it is preferable that the layer containing the alicyclic structure-containing resin is subjected to a sterilization treatment. The sterilization method is not particularly limited, but EO sterilization is preferable. As described above, the film according to this embodiment can improve the impact strength in a low-temperature environment even after EO sterilization, and therefore the durability of the container against a low-temperature environment after EO sterilization can be improved.

[0114] The container according to the present invention can generally be used for the cryopreservation of medicines. Here, "medicines" include pharmaceuticals such as drugs for diagnosing, treating, and preventing diseases in humans and animals, as well as biochemical materials used for pharmaceutical research, etc. The dosage form of the medicine is not particularly limited.

[0115] The drug is not particularly limited, but preferably contains a biochemical material, because the alicyclic structure-containing resin contained in the film constituting the container is less likely to adsorb biochemical substances, allowing the drug to be preserved in good condition.

[0116] A biochemical material typically refers to a liquid material containing biochemicals dissolved or dispersed in a solvent. The biochemical material may also contain other components besides biochemicals. Examples of biochemicals include proteins, enzymes, antibodies, polypeptides, oligopeptides, amino acids, nucleic acids, lipids, polysaccharides, oligosaccharides, amino sugars, microorganisms, and viruses. Nucleic acids include both ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Biochemicals are not limited to those obtained by extraction or other methods from biological materials, but also include those chemically synthesized outside of living organisms. The solvent is not particularly limited as long as it can dissolve or disperse biochemicals, and examples include water. The concentration of the biochemicals in the biochemical material is not particularly limited, but is preferably 10,000 mg / L or less, more preferably 1,000 mg / L or less, and even more preferably 100 mg / L or less. If the concentration of the biochemical substance in the biochemical substance material is 10,000 mg / L or less, the adsorption of the biochemical substance on the surface of the container that comes into contact with the biochemical substance material can be more effectively suppressed.

[0117] The container according to the present invention is usually stored in a refrigerated environment after the drug is sealed in. The freezing temperature is adjusted appropriately depending on the type and use of the drug, and specifically, can be the same as the temperature (freezing temperature) of the environment in which the film is used during the above-mentioned frozen storage.

[0118] The present invention will be described in detail below with reference to examples. However, the present invention is not limited to the examples shown below, and can be practiced with any modifications within the scope of the claims of the present invention and their equivalents.

[0119] In the following description, "%" and "parts" representing amounts are by weight unless otherwise specified. Furthermore, the operations described below were carried out in air at room temperature and normal pressure (23°C, 1 atmosphere) unless otherwise specified.

[0120] [Evaluation Method] (Method for Measuring Charpy Impact Strength) As described below, test specimen 1 (unnotched, 80 mm long x 10 mm wide x 4 mm thick) was prepared using pellet A of Production Example 1-1, and subjected to EO sterilization (A). EO sterilization (A) was performed by placing the test specimen in a 3M EO gas sterilizer (Steri-Bag EO Gas Sterilizer) and exposing it to an ethylene oxide gas atmosphere (ethylene oxide gas concentration: 30 wt%) at a temperature of 50°C and a relative humidity of 50% for 6 hours. A mixed gas of ethylene oxide gas and carbon dioxide with an ethylene oxide gas concentration of 30 wt% was used as the treatment gas. Furthermore, as a pretreatment for EO sterilization (A), the test specimen was left to stand in an environment at a temperature of 50°C and a relative humidity of 50% for 13 hours. After EO sterilization (A), the specimen was aerated for 24 hours in a closed space at a temperature of 50°C and a relative humidity of 50%.

[0121] Using test piece 1 after EO sterilization treatment (A), the Charpy impact strength was measured at a measurement temperature of 23°C in accordance with ISO 179-1. Five test pieces 1 after EO sterilization treatment (A) were prepared, and the above measurement was performed five times. The average of the five measurement results was taken as the Charpy impact strength S(23) of the resin contained in pellet A measured at 23°C after EO sterilization treatment (A). The Charpy impact strength S(-80) of the resin contained in pellet A measured at -80°C after EO sterilization treatment (A) and the Charpy impact strength S(-194) of the resin contained in pellet A measured at -194°C after EO sterilization treatment (A) were also measured in the same manner as the Charpy impact strength (23) after EO sterilization treatment (A).

[0122] As will be described later, test pieces 2 to 8 were prepared using pellets B to F of Production Examples 1-2 to 1-6, and subjected to EO sterilization treatment (A). The Charpy impact strengths S(23), S(-80), and S(-194) of the resins contained in pellets B to F of Production Examples 1-2 to 1-6, measured at measurement temperatures of 23°C, -80°C, and -194°C, respectively, after the EO sterilization treatment (A), were also measured in the same manner as for the resin contained in pellet A.

[0123] (Durability Test of Films in a Low-Temperature Environment) For the films of Examples 1 to 8 and Comparative Examples 2 to 4, films were punched out into 1 m x 1 m squares and subjected to EO sterilization. The conditions were the same as those for the EO sterilization treatment (A) performed on the Charpy impact strength test specimens. The films were then folded in half 180 degrees and stored in a creased state in a -80°C environment for 1 hour. The films were then returned to room temperature and the condition of the films was visually evaluated. The films of Examples 9 and 10 were evaluated in the same manner as the film of Example 1, except that the storage temperature was changed to -198°C. The film of Comparative Example 1 was evaluated in the same manner as the film of Example 1, except that the storage temperature was changed to 23°C. The evaluation was based on the following criteria: 3: The film was in the same condition as before low-temperature storage. 2: The fold marks on the film had become larger, but no cracks had occurred. 1: The film cracked and was unusable.

[0124] (Production Example 1-1: Production of Hydrogenated Ring-Opened Copolymer A) A dried polymerization reactor purged with nitrogen was charged with tricyclo[4.3.0.1 ２，５ ]deca-3,7-diene (DCPD), 8-methyltetracyclo[4.4.0.1 ２，５ .1 ７，１０ ] dodec-3-ene (TCD), and bicyclo[2.2.1]hept-2-ene (NB) (weight ratio DCPD: TCD: NB = 33:31:36) monomer mixture 7 parts, 1600 parts of dehydrated cyclohexane, 3.5 parts of 1-hexene as a molecular weight regulator, 1.3 parts of diisopropyl ether, 0.33 parts of isobutyl alcohol, 0.84 parts of triisobutylaluminum, and 30 parts of a 0.66% cyclohexane solution of tungsten hexachloride were added, and stirred for 10 minutes at 55 ° C. Then, while maintaining the reaction system at 55 ° C., 93 parts of a monomer mixture having the same composition as the monomer mixture described above and 72 parts of a 0.77% cyclohexane solution of tungsten hexachloride were added dropwise over 150 minutes, and after the completion of the dropwise addition, the mixture was stirred for 30 minutes and then 1.0 parts of isopropyl alcohol was added to terminate the polymerization reaction. The polymerization reaction solution was analyzed by gas chromatography, and the conversion rate of the monomer to the polymer was found to be 100%.

[0125] Next, 300 parts of the polymerization reaction solution containing the polymer was transferred to an autoclave equipped with a stirrer, and 100 parts of cyclohexane and 2.0 parts of a diatomaceous earth-supported nickel catalyst ("T8400RL" manufactured by Nikki Chemical Industries, Ltd., nickel loading rate 58%) were added. After replacing the atmosphere in the autoclave with hydrogen, the reaction was carried out for 6 hours at 170 ° C. under a hydrogen pressure of 4.9 MPa. The solution was filtered through a stainless steel wire mesh filter equipped with diatomaceous earth ("Radiolite #500" manufactured by Showa Chemical Industry Co., Ltd.) as a filter aid to remove the catalyst. The resulting reaction solution was poured into 8,000 parts of isopropyl alcohol with stirring to precipitate the hydride, which was then filtered. Further, after washing with 500 parts of acetone, 0.13 × 10 ３ The copolymer was dried for 24 hours in a vacuum dryer set at 65°C or less at a pressure of 100 Pa to obtain a hydrogenated ring-opened copolymer A. The hydrogenation rate of the hydrogenated ring-opened copolymer A was 99.9%, and the glass transition temperature was 68°C.

[0126] Next, the hydrogenated ring-opened copolymer A was extruded in a molten state from an extruder in the form of a strand, cooled, and then pelletized to obtain pellets A.

[0127] (Production Example 1-2: Production of Ring-Opened Copolymer Hydrogenation Product B) Under a nitrogen atmosphere, 500 parts of dehydrated cyclohexane, 0.82 parts of 1-hexene, 0.15 parts of dibutyl ether, and 0.30 parts of triisobutylaluminum were placed in a reactor at room temperature (25°C) and mixed. Then, while maintaining the temperature at 45°C, 76 parts of DCPD, tetracyclo[7.4.0.0]diisobutylaluminum, and 1.0 parts of 1-hexene were added as monomers. ２，７ .1 １０，１３ ] 54 parts of trideca-2,4,6,11-tetraene (MTF) and 70 parts of TCD (a monomer mixture with a weight ratio of DCPD:MTF:TCD of 38:27:35) and 80 parts of tungsten hexachloride (0.7% toluene solution) were continuously added in parallel over a period of 2 hours to polymerize. Next, 1.06 parts of butyl glycidyl ether and 0.52 parts of isopropyl alcohol were added to the polymerization solution to inactivate the polymerization catalyst and terminate the polymerization reaction. When the reaction solution containing the obtained ring-opened polymer was analyzed by gas chromatography, the polymerization conversion of each monomer was found to be 99.5%.

[0128] Next, 270 parts of cyclohexane was added to 100 parts of the reaction solution containing the obtained ring-opened polymer, and 5 parts of a diatomaceous earth-supported nickel catalyst (Nissan Girdler G-96D; nickel loading: 58%) was further added as a hydrogenation catalyst. The mixture was pressurized to 5 MPa with hydrogen and heated to 200°C with stirring, and then reacted for 8 hours to obtain a reaction solution containing a DCPD / MTF / TCD ring-opened copolymer hydrogenated product. The hydrogenation catalyst was removed by filtration, and then the solution was subjected to a cylindrical concentrating dryer (Hitachi, Ltd.) at a temperature of 270°C and a pressure of 1 kPa or less to remove the cyclohexane solvent and other volatile components, thereby obtaining a ring-opened copolymer hydrogenated product B. The hydrogenation rate of the ring-opened copolymer hydrogenated product B was 99.8%, and the glass transition temperature was 136°C. Next, in the same manner as in Production Example 1-1, the ring-opened copolymer hydrogenated product B was pelletized to obtain pellets B.

[0129] (Production Example 1-3: Production of ring-opened copolymer hydrogenated product C) A ring-opened copolymer hydrogenated product C was produced in the same manner as in Production Example 1-1, except that the combination of the monomer mixture was 60 parts MTF and 40 parts TCD, and pelletized to obtain pellets C. The hydrogenation rate of the ring-opened copolymer hydrogenated product C was 99.9%, and the glass transition temperature was 158°C.

[0130] (Production Example 1-4: Production of Hydrogenated Ring-Opened Copolymer D) 250 parts of dehydrated cyclohexane were placed in a reactor under a nitrogen atmosphere at room temperature (25°C), and 0.84 parts of 1-hexene, 0.06 parts of dibutyl ether, and 0.11 parts of triisobutylaluminum were further added and mixed. After that, 85 parts of DCPD and 8-ethyltetracyclo[4.4.0.1] were added while maintaining the temperature at 45°C. ２，５ .1 ７，１０15 parts of ] dodec-3-ene (ETD) (a monomer mixture with a weight ratio of DCPD:ETD of 85:15) and 15 parts of tungsten hexachloride (0.7% toluene solution) were continuously added over 2 hours to polymerize the mixture. Gas chromatography analysis of the resulting reaction solution containing the ring-opened polymer revealed that the polymerization conversion of each monomer was 100%. The resulting polymerization reaction solution was transferred to a pressure-resistant hydrogenation reactor, and 5 parts of a diatomaceous earth-supported nickel catalyst (Nissan Girdler "G-96D"; nickel loading: 58%) and 100 parts of cyclohexane were added as a hydrogenation catalyst. The reaction mixture was reacted at 150°C and a hydrogen pressure of 4.4 MPa for 8 hours. The reaction solution was pressure-filtered (Fundafilter, Ishikawajima-Harima Heavy Industries Co., Ltd.) at a pressure of 0.25 MPa using diatomaceous earth (Showa Chemical Industry Co., Ltd. "Radiolite #500") as a filter bed to remove the hydrogenation catalyst. Next, pellets D of a hydrogenated ring-opening copolymer (hydrogenated ring-opening polymer D of cyclic olefin) were obtained in the same manner as in Production Example 1-1. The hydrogenation rate of hydrogenated ring-opening copolymer D was 99.6%, and the glass transition temperature was 102°C.

[0131] (Production Example 1-5: Preparation of cyclic olefin copolymer) Pellets E manufactured by TOPAS ADVANCED POLYMERS, Inc. under the trade name "TOPAS6013S-04" were prepared as a resin containing a cyclic olefin copolymer (COC resin).

[0132] (Production Example 1-6: Preparation of polypropylene resin) Pellets F of the trade name "Excellen AR244M" manufactured by Sumitomo Chemical Co., Ltd. were prepared as a polypropylene (PP) resin.

[0133] (Production Example 2: Production of test pieces for Charpy impact test) Test pieces for measuring Charpy impact strength were produced from the pellets A to F prepared in Production Examples 1-1 to 1-6 by the following procedure.

[0134] (Production Example 2-1: Production of Test Piece 1) A test piece for Charpy impact strength was produced according to the following procedure. Pellets A were dried at 50°C for 2 hours. Next, nitrogen was sealed inside a hopper attached to an injection molding machine (FANUC ROBOSHOT S2000i 100A, mold: ISO527 type) to adjust the oxygen concentration to 800 ppm. Next, the dried pellets A were supplied into the hopper with the adjusted oxygen concentration, and the resin temperature was 250°C, the mold temperature was 50°C, the injection speed was 3 mm / s, and the injection pressure was 1500 kgf / cm. ２ , holding pressure 1200kgf / cm ２ , and back pressure 50 kgf / cm ２ Test piece 1 was obtained by injection molding under the conditions of

[0135] (Production Example 2-2: Production of Test Piece 2) Pellet B was used instead of pellet A, the drying temperature of pellet B was 100°C, and in injection molding, the resin temperature was 280°C, the mold temperature was 105°C, and the injection pressure was 1200 kgf / cm ２ , holding pressure 1100kgf / cm ２ Test piece 2 was obtained in the same manner as in Production Example 2-1, except that:

[0136] (Production Example 2-3: Production of Test Piece 3) Test piece 3 was obtained in the same manner as in Production Example 2-1, except that pellet C was used instead of pellet A, the drying temperature of pellet C was set to 120°C, and in injection molding, the resin temperature was set to 300°C and the mold temperature was set to 120°C.

[0137] (Production Example 2-4: Production of Test Piece 4) Test piece 4 was obtained in the same manner as in Production Example 2-1, except that pellet D was used instead of pellet A, the drying temperature of pellet D was set to 80°C, and in injection molding, the resin temperature was set to 270°C and the mold temperature was set to 80°C.

[0138] (Production Example 2-5: Production of Test Piece 5) Test piece 5 was obtained in the same manner as in Production Example 2-1, except that pellet E was used instead of pellet A, the drying temperature of pellet E was set to 100°C, and in injection molding, the resin temperature was set to 280°C and the mold temperature was set to 105°C.

[0139] (Production Example 2-6: Production of Test Piece 6) Pellet F was used instead of pellet A, the drying temperature of pellet F was set to 60°C, and in injection molding, the resin temperature was set to 240°C, the mold temperature was set to 70°C, and the holding pressure was set to 1000 kgf / cm ２ Test piece 6 was obtained in the same manner as in Production Example 2-1, except that:

[0140] (Production Example 2-7: Production of Test Piece 7) Test piece 7 was obtained in the same manner as in Production Example 2-4, except that the resin was not dried and that injection molding was performed without sealing nitrogen inside the hopper attached to the injection molding machine. The production conditions for test piece 7 corresponded to the production conditions for Example 1 in JP 2001-064525 A.

[0141] (Production Example 2-8: Production of Test Piece 8) Test piece 8 was obtained in the same manner as in Production Example 2-2, except that the resin was not dried and that injection molding was performed without sealing nitrogen inside the hopper attached to the injection molding machine. The production conditions for test piece 8 correspond to the production conditions for Example 2 of JP 2001-064525 A.

[0142] [Examples 1 and 9] Pellets A obtained in Production Example 1-1 were dried at 50°C for 2 hours. A T-die film extrusion molding machine equipped with a vacuum hopper was prepared, and the dried pellets were supplied into the vacuum hopper (vacuum degree: 0.5 kPa) and extruded onto a cast roll at a resin temperature of 210°C to produce a film with a thickness of 60 µm. The Charpy impact strength of the resin contained in the films of Examples 1 and 9 corresponds to the Charpy impact strength of test piece 1.

[0143] [Example 2] A film having a thickness of 60 μm was produced in the same manner as in Example 1, except that pellets B were used instead of pellets A, the drying temperature of the resin was set to 100° C., and the temperature of the resin extruded from the extruder was set to 250° C. The Charpy impact strength of the resin contained in the film of Example 2 corresponds to the Charpy impact strength of test piece 2.

[0144] [Examples 3 and 10] Films with a thickness of 60 μm were produced in the same manner as in Example 1, except that pellets C were used instead of pellets A, the drying temperature for the resin was set to 120° C., and the temperature of the resin extruded from the extruder was set to 280° C. The Charpy impact strength of the resin contained in the film of Example 3 corresponds to the Charpy impact strength of test piece 3.

[0145] [Example 4] A film having a thickness of 60 μm was produced in the same manner as in Example 1, except that pellet D was used instead of pellet A, the drying temperature of the resin was set to 80° C., and the temperature of the resin extruded from the extruder was set to 230° C. The Charpy impact strength of the resin contained in the film of Example 4 corresponds to the Charpy impact strength of test piece 4.

[0146] [Example 5] A multilayer film having a three-layer structure including a first resin layer, a second resin layer, and a third resin layer in this order in the thickness direction was produced by the following procedure: Ring-opening copolymer hydrogenated product A (pellets A) was used as the resin contained in the first resin layer, pelleted polyvinyl alcohol (PVA) resin was used as the resin contained in the second resin layer, and pelleted high-density polyethylene (HDPE) resin was prepared as the resin contained in the third resin layer, and each was dried at 50°C for 2 hours.

[0147] Next, a film-forming apparatus was prepared, including a multi-manifold die capable of coextrusion film formation of three layers, three extruders connected to the multi-manifold die, and vacuum hoppers attached to each extruder. Dried pellets A were loaded into one vacuum hopper and fed from the extruder to the multi-manifold die at a resin temperature of 210°C. Dried pellet-shaped PVA resin was loaded into another vacuum hopper and fed from the extruder to the multi-manifold die at a resin temperature of 180°C. Furthermore, dried HDPE resin was loaded into a vacuum hopper separate from the two vacuum hoppers described above and fed from the extruder to the multi-manifold die at a resin temperature of 150°C. The vacuum level in the vacuum hopper was the same as in Example 1.

[0148] Next, the hydrogenated ring-opening copolymer A, PVA resin, and HDPE resin were extruded from a multi-manifold die onto a cooling roll to form a film containing three layers: a first resin layer, a second resin layer, and a third resin layer, thereby obtaining a three-layer multilayer film. The total thickness of the film was 220 μm, and the thicknesses of the individual layers were 60 μm for the first resin layer, 20 μm for the second resin layer, and 140 μm for the third resin layer. The Charpy impact strength of the resin contained in the first resin layer in Example 5 corresponds to the Charpy impact strength of test piece 1.

[0149] [Example 6] A three-layer multilayer film was produced in the same manner as in Example 5, except that the thickness of each layer in the three-layer multilayer film was changed to 154 μm for the first resin layer, 20 μm for the second resin layer, and 46 μm for the third resin layer. The Charpy impact strength of the resin contained in the first resin layer in Example 6 corresponds to the Charpy impact strength of Test Piece 1.

[0150] [Example 7] A film was produced in the same manner as in Example 1, except that the film thickness was set to 20 μm. The Charpy impact strength of the resin contained in the film of Example 7 corresponds to the Charpy impact strength of Test Piece 1.

[0151] [Example 8] A film was produced in the same manner as in Example 1, except that the film thickness was set to 320 µm. The Charpy impact strength of the resin contained in the film of Example 8 corresponds to the Charpy impact strength of Test Piece 1.

[0152] Comparative Example 1 A film was produced in the same manner as in Example 1, except that pellets E were used instead of pellets A, the resin drying temperature was 100°C, the temperature of the resin extruded from the extruder was 250°C, and the film thickness was 100 µm. The Charpy impact strength of the resin contained in the film of Comparative Example 1 corresponds to the Charpy impact strength of test piece 5.

[0153] Comparative Example 2 A film having a thickness of 60 μm was produced in the same manner as in Example 1, except that pellet F was used instead of pellet A, the drying temperature of the resin was set to 40° C., and the temperature of the resin extruded from the extruder was set to 190° C. The Charpy impact strength of the resin contained in the film of Comparative Example 2 corresponds to the Charpy impact strength of Test Piece 6.

[0154] [Comparative Example 3] A film was obtained in the same manner as in Example 4, except that pellets D were not dried and that pellets D were supplied to the extruder without using a vacuum hopper. The Charpy impact strength of the resin contained in the film of Comparative Example 3 corresponds to the Charpy impact strength of test piece 7.

[0155] [Comparative Example 4] A film was obtained in the same manner as in Example 2, except that pellets B were not dried and that pellets B were supplied to the extruder without using a vacuum hopper. The Charpy impact strength of the resin contained in the film of Comparative Example 4 corresponds to the Charpy impact strength of test piece 8.

[0156] The evaluation results are shown in Tables 1 to 3. The abbreviations in the tables are as follows. Polymer type "A": Hydrogenated ring-opened copolymer A (a polymer containing an alicyclic structure using a monomer mixture of DCPD:TCD:NB = 33:31:36 by weight) Polymer type "B": Hydrogenated ring-opened copolymer B (a polymer containing an alicyclic structure using a monomer mixture of DCPD:MTF:TCD = 38:27:35 by weight) Polymer type "C": Hydrogenated ring-opened copolymer C (a polymer containing an alicyclic structure using a monomer mixture of MTF:TCD = 60:40 by weight) Polymer type "D": Hydrogenated ring-opened copolymer D (a polymer containing an alicyclic structure using a monomer mixture of DCPD:ETD = 85:15 by weight) Polymer type "E": Cycloolefin copolymer (COC) Polymer type "F": Polypropylene (PP) S (23): Charpy impact strength of the resin measured at 23°C after EO sterilization treatment (A) S (-80): Charpy impact strength of resin measured at -80 ° C after EO sterilization treatment (A) S (-194): Charpy impact strength of resin measured at -194 ° C after EO sterilization treatment (A) Film thickness ratio (t １ / tｔｏｔａｌ ): total film thickness (t ｔｏｔａｌ ) (μm) of the layer containing the alicyclic structure-containing resin (t １ ) (μm) ratio

[0157]

[0158]

[0159]

[0160] As shown in Examples 1 to 10, it was confirmed that films having a layer containing an alicyclic structure-containing resin with a specific Charpy impact strength can maintain good impact strength in a low-temperature environment after EO sterilization. On the other hand, it was confirmed that the film containing COC resin shown in Comparative Example 1 cracked at room temperature (23°C) after EO sterilization, rendering it unusable. Furthermore, it was confirmed that the film containing PP resin shown in Comparative Example 2 cracked at a low temperature, such as -80°C, rendering it unusable.

[0161] Furthermore, as shown in Comparative Examples 3 and 4, it was confirmed that even in a film containing an alicyclic structure-containing resin, if the alicyclic structure-containing resin does not have a specific Charpy impact strength, cracks will occur in a low-temperature environment such as -80°C, making the film unusable.

Claims

1. A film for frozen storage, comprising at least one layer containing an alicyclic structure-containing resin, wherein the alicyclic structure-containing resin has a Charpy impact strength S(23) of 100 kJ / m or less when measured at 23°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours. ２ or more, and the Charpy impact strength S(-80) of the alicyclic structure-containing resin measured at -80°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours satisfies the following formula (1): S(-80) / S(23)≧0.7 (1) 2. The film according to claim 1, wherein the Charpy impact strength S(23) and the Charpy impact strength S(-80) satisfy the following formula (2): S(-80) / S(23)≧0.8 (2) 3. The film according to claim 1, wherein the Charpy impact strength S(23) and the Charpy impact strength S(-194) of the alicyclic structure-containing resin measured at -194°C after ethylene oxide (EO) sterilization treatment in which the alicyclic structure-containing resin is exposed to ethylene oxide gas at a temperature of 50°C and a relative humidity of 50% for 6 hours satisfy the following formula (3): S(-194) / S(23)≧0.25 (3) 4. The alicyclic structure-containing resin is a tricyclo[4.3.0.1 ２，５ 2. The film according to claim 1, comprising a polymer containing a deca-3,7-diene skeleton.

5. The film according to claim 1, wherein the film comprises a first resin layer containing the alicyclic structure-containing resin and a second resin layer, and the second resin layer contains at least one resin selected from the group consisting of hydrogenated styrene-based thermoplastic elastomer resin, polyvinyl alcohol resin, ethylene vinyl alcohol resin, linear low-density polyethylene resin, and polypropylene resin.

6. The film according to claim 1, wherein the layer containing the alicyclic structure-containing resin has been subjected to ethylene oxide (EO) sterilization.

7. The film according to any one of claims 1 to 6, wherein the total thickness of the film is from 10 μm to 350 μm, and the ratio of the thickness of the layer containing the alicyclic structure-containing resin to the total thickness of the film is from 0.2 to 1.

0.

8. A container for cryopreservation used for storing medicines, the container comprising the film according to claim 1.

9. The container according to claim 8, wherein a layer of the film containing the resin having an alicyclic structure is placed inside the container, and the layer containing the resin having an alicyclic structure has been subjected to a sterilization treatment.

10. The container of claim 8, wherein the container has a bag shape.

11. The container of claim 8, wherein the agent comprises a biochemical material.

12. A method for producing the film according to claim 1, comprising the steps of: (1) drying an alicyclic structure-containing resin; and (2) forming the dried alicyclic structure-containing resin into a film by extrusion, wherein step (2) is carried out in an inert gas atmosphere or under reduced pressure.

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