JPH05277154A - Transfusion bag for medical treatment - Google Patents

Abstract

(57) [Summary] [Object] To provide a medical infusion bag made of a resin having high heat stability without adding a stabilizer and having excellent heat sealability, fluidity and liquid resistance. [Structure] At least the innermost layer has an α-olefin unit and a cyclic olefin unit and has a glass transition temperature (Tg) of 7
A medical infusion bag is formed from a film provided with a cyclic olefin-based copolymer layer having a temperature of 0 ° C. or lower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infusion bag used for filling and sealing a medical infusion solution. More specifically, a resin excellent in heat stability, liquid resistance and heat sealability is used. The present invention relates to a medical infusion bag.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
As a medical infusion bag, a bag made of a relatively flexible soft vinyl chloride resin or ethylene / vinyl acetate copolymer resin is often used. Since these infusion bags are a closed system that does not require a ventilating needle at the time of infusion, they have the advantage of not being contaminated by the outside air, but since the infusion bags of soft vinyl chloride resin contain additives such as plasticizers and stabilizers, There is a problem that it is necessary to prevent the elution, and the infusion bag of the ethylene / vinyl acetate copolymer resin is inferior in heat resistance, and therefore needs to be crosslinked.

On the other hand, attempts have been made to solve the above problems by using a polyolefin resin such as linear low-density polyethylene or polypropylene in a single layer or by laminating it. JP-A-61-1
35664). However, these polyolefin-based resins, particularly polypropylene, when used without adding additives such as antioxidants and heat stabilizers for effective use in the medical field, thermal deterioration occurs and fluidity decreases. There was a problem to do. Further, these polyolefin-based resins have not been sufficiently satisfactory in terms of heat-sealing strength such as heat-sealing strength and heat-sealing temperature.

The present invention has been made in view of the above circumstances, and is made from a resin having high heat stability without adding a stabilizer and having excellent heat sealability, melt fluidity, liquid resistance and elasticity. It aims at providing the medical infusion bag which becomes.

[0005]

As a result of intensive studies, the present inventors have formed a medical infusion bag using a cyclic olefin copolymer having a specific structure having a specific glass transition temperature (Tg). In the case of doing so, they have found that the above requirements can be satisfied, and have completed the present invention.

That is, the present invention is a cyclic olefin copolymer having a repeating unit derived from an α-olefin and a repeating unit derived from a cyclic olefin and having a glass transition temperature (Tg) of 70 ° C. or lower, and at least an inner layer thereof. There is provided a medical infusion bag characterized by comprising:

The present invention will be described in more detail below.
The medical infusion bag of the present invention has at least the inner layer formed of a cyclic olefin-based copolymer having an α-olefin unit and a cyclic olefin unit. Here, the above α-olefin is not necessarily limited, but for example, the following general formula [X]

[Chemical 1] (In the formula [X], R ^a represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms).

In the repeating unit represented by the above general formula [X], R ^a represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. Here, as the hydrocarbon group having 1 to 20 carbon atoms, specifically, for example, methyl group, ethyl group, isopropyl group, n-propyl group, isobutyl group, n-butyl group, n-hexyl group, n-octyl group. Group, n-octadecyl group and the like. In addition, the general formula [X]
Specific examples of the α-olefin giving the repeating unit represented by are, for example, ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, Examples thereof include 1-decene and 1-eicosene.

Further, the cyclic olefin is not necessarily limited, but for example, the following general formula [Y]

[Chemical 2] (In the formula [Y], R ^{b to} R ^m are each a hydrogen atom or a carbon number 1
~ 20 represents a hydrocarbon group or a substituent containing a halogen atom, an oxygen atom or a nitrogen atom, and n represents an integer of 0 or more. R ^j or R ^k and R ¹ or R ^m may form a ring with each other. R ^{b to} R ^m may be the same or different from each other. ) And those which give a repeating unit.

In the repeating unit represented by the above general formula [Y], R ^{b to} R ^m are each a hydrogen atom or a carbon number 1
To 20 hydrocarbon groups or substituents containing a halogen atom, an oxygen atom or a nitrogen atom. Here, as the hydrocarbon group having 1 to 20 carbon atoms, specifically, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n
-Butyl group, isobutyl group, t-butyl group, hexyl group and other alkyl groups having 1 to 20 carbon atoms, phenyl group, tolyl group, aryl group having 6 to 20 carbon atoms such as benzyl group, alkylaryl group or arylalkyl Group, methylidene group, ethylidene group, propylidene group, etc., having 1 to 2 carbon atoms
0 alkylidene group, vinyl group, allyl group, etc. with 2 carbon atoms
To 20 alkenyl groups and the like. However,
R ^b , R ^c , R ^f and R ^g exclude alkylidene groups. In addition, R
^{When any of d} , R ^e and R ^{h to} R ^m is an alkylidene group,
The carbon atom to which it is attached has no other substituents.

Specific examples of the substituent containing a halogen atom include halogen groups such as fluorine, chlorine, bromine and iodine, and halogen substitution having 1 to 20 carbon atoms such as chloromethyl group, bromomethyl group and chloroethyl group. An alkyl group etc. can be mentioned. Specific examples of the substituent containing an oxygen atom include an alkoxy group having 1 to 20 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a phenoxy group, and a carbon number 1 to 20 such as a methoxycarbonyl group and an ethoxycarbonyl group. Alkoxycarbonyl group and the like can be mentioned. Specifically as a substituent containing a nitrogen atom,
For example, a C1-C20 alkylamino group, such as a dimethylamino group and a diethylamino group, a cyano group, etc. can be mentioned.

Specific examples of the cyclic olefin providing the repeating unit represented by the general formula [Y] include, for example, norbornene, 5-methylnorbornene, 5-ethylnorbornene, 5-propylnorbornene, 5,6-dimethylnorbornene, 1 -Methylnorbornene, 7-methylnorbornene, 5,5,6-trimethylnorbornene, 5-
Phenylnorbornene, 5-benzylnorbornene, 5
-Ethylidene norbornene, 5-vinyl norbornene,
1,4,5,8-dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene, 2-methyl-
1,4,5,8-dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene, 2-ethyl-
1,4,5,8-dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene, 2,3-dimethyl-1,4,5,8-dimethano-1,2,3,4,4
a, 5,8,8a-octahydronaphthalene, 2-hexyl-1,4,5,8-dimethano-1,2,3,4,4
a, 5,8,8a-octahydronaphthalene, 2-ethylidene-1,4,5,8-dimethano-1,2,3,4
4a, 5,8,8a-octahydronaphthalene, 2-fluoro-1,4,5,8-dimethano-1,2,3,4
4a, 5,8,8a-octahydronaphthalene, 1,5
-Dimethyl-1,4,5,8-dimethano-1,2,3
4,4a, 5,8,8a-octahydronaphthalene, 2
-Cyclohexyl-1,4,5,8-dimethano-1,
2,3,4,4a, 5,8,8a-octahydronaphthalene, 2,3-dichloro-1,4,5,8-dimethano-
1,2,3,4,4a, 5,8,8a-octahydronaphthalene, 2-isobutyl-1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a- Octahydronaphthalene, 1,2-dihydrodicyclopentadiene,
5-chloronorbornene, 5,5-dichloronorbornene, 5-fluoronorbornene, 5,5,6-trifluoro-6-trifluoromethylnorbornene, 5-chloromethylnorbornene, 5-methoxynorbornene,
Examples thereof include 5,6-dicarboxyl norbornene anhydrate, 5-dimethylamino norbornene, and 5-cyanonorbornene. Among these, norbornene or its derivative is particularly preferable.

The cyclic olefin copolymer used in the present invention is basically a copolymer of the above-mentioned α-olefin and a cyclic olefin, but it is within the range not impairing the object of the present invention. So, in addition to these two essential components,
If necessary, other copolymerizable unsaturated monomer components may be used. As such an unsaturated monomer which may be optionally copolymerized, specifically, among the above α-olefin components, those not previously used, among the above cyclic olefin components, Examples thereof include those not used, cyclic dienes such as dicyclopentadiene and norbornadiene, chain dienes such as butadiene, isoprene and 1,5-hexadiene, and monocyclic olefins such as cyclopentene and cycloheptene.

The cyclic olefin-based copolymer used in the present invention has an α-olefin unit content [x] and a cyclic olefin unit content [y] of [x] of 80 to 99.9 mol%. [Y] is 20 to 0.1 mol%, particularly [x] is 82 to 99.5 mol%, [y] is 18 to 0.5 mol%, and in particular [x] is 85 to 98 mol%. [Y] is 1
It is preferably from 5 to 2 mol%. If the content [x] of α-olefin units is less than 80 mol%, the glass transition temperature (Tg) and tensile elastic modulus of the copolymer become high, and the elastic recovery, impact resistance and elasticity of the infusion bag are increased. May be insufficient. On the other hand, when the content [y] of the cyclic olefin unit is less than 0.1 mol%, the crystallinity of the copolymer becomes high, and the effects of introducing the cyclic olefin component such as transparency and elastic recovery become insufficient. May be.

The cyclic olefin copolymer used in the present invention is a substantially linear copolymer in which α-olefin units and cyclic olefin units are linearly arranged, and does not have a gel-like crosslinked structure. It is preferably one. It can be confirmed that the copolymer does not have a gel-like crosslinked structure by completely dissolving the copolymer in decalin at 135 ° C.

The cyclic olefin copolymer used in the present invention preferably has an intrinsic viscosity [η] measured in decalin at 135 ° C. of 0.01 to 20 dl / g. If the intrinsic viscosity [η] is less than 0.01 dl / g, the strength may be significantly reduced, and if it exceeds 20 dl / g, the moldability may be significantly deteriorated. A more preferable intrinsic viscosity [η] is 0.05 to 10 dl / g.

The molecular weight of the cyclic olefin copolymer used in the present invention is not particularly limited, but the weight average molecular weight Mw measured by gel permeation chromatography (GPC) [polyethylene conversion] is 1,0.
00 to 2,000,000, especially 5,000 to 100
50,000, the number average molecular weight Mn is 500 to 1,000,
000, particularly 2,000 to 800,000, and a molecular weight distribution (Mw / Mn) of 1.3 to 4, particularly 1.4 to 3. When the molecular weight distribution (Mw / Mn) is greater than 4, the content of low molecular weight substances increases, which may cause stickiness of the infusion bag.

The cyclic olefin copolymer used in the present invention is required to have a glass transition temperature (Tg) of 70 ° C. or lower. By using such a copolymer, it is possible to obtain an infusion bag having excellent thermal stability and liquid resistance, in particular, since there is no need for or little addition of a stabilizer and there is no fear of elution. More preferable glass transition temperature (Tg) is -50 to 5
It is 0 ° C., especially −30 to 30 ° C. In this case, the glass transition temperature (Tg) of the cyclic olefin-based copolymer used in the present invention can be arbitrarily controlled by changing the type and composition of the monomer, and the intended use and use can be achieved. The glass transition temperature (Tg) can be arbitrarily changed according to the temperature and the like.

The cyclic olefin copolymer used in the present invention has a crystallinity of 0 to 4 as measured by X-ray diffractometry.
It is preferably 0%. When the crystallinity exceeds 40%, elastic recovery and transparency may be deteriorated. More preferable crystallinity is 0 to 30%, especially 0 to 25%.

The cyclic olefin copolymer used in the present invention preferably has a tensile elastic modulus of less than 3,000 Kg / cm ² . When the tensile modulus is 3,000 Kg / cm ² or more, the impact resistance of the infusion bag may be insufficient. More preferable tensile elastic modulus is 50 to 2,000K
It is g / cm ² .

The cyclic olefin copolymer used in the present invention preferably has an elastic recovery rate of 20% or more. If the elastic recovery rate is less than 20%, the shape of the infusion bag may be deformed by an external force, or the thickness may be partially reduced to reduce the strength. A more preferable elastic recovery rate is 30% or more, and particularly 40% or more. Note that the elastic recovery rate was 6 mm in width at a pulling speed of 62 mm / min using an autograph.
A measurement piece with a distance between clamps of 50 mm (L ₀ ) is stretched and stretched by 150%, the state is maintained for 5 minutes, and then it is abruptly contracted without being repelled, and after 1 minute, the length of the sheet between the clamps (L ₁ ) Is a value obtained by the following formula. Elastic recovery rate (%) = [1-{(L ₁ −L ₀ ) / L ₀ }] ×
100

The cyclic olefin copolymer used in the present invention preferably has a broad melting peak by DSC (temperature rise measurement) of less than 90 ° C. DSC (temperature rise measurement)
The copolymer having a sharp melting peak at 90 ° C. or higher has a broad composition distribution of the copolymer of cyclic olefin and α-olefin, and the elastic recovery of the infusion bag may be insufficient. The broad melting peak by DSC (temperature rise measurement) is more preferably in the range of 10 to 85 ° C. In DSC (temperature rise measurement), the melting point (melting peak) of the olefin-based copolymer is not sharply seen, and particularly in the case of low crystallinity, almost no peak appears at the level of ordinary polyethylene measurement conditions. Does not appear. The cyclic olefin-based copolymer used in the present invention has a crystallization peak by DSC (temperature drop measurement),
It is preferable to have one or more sub-peaks that are relatively small on the high temperature side of the main peak. Due to the characteristics of the thermal properties described above, the physical properties of the infusion bag can be obtained, and the infusion bag can be stably molded, for example, the molding temperature range is widened.

The cyclic olefin-based copolymer used in the present invention may be a copolymer having only the physical properties in the above range, and may partially include the copolymer having the physical properties outside the above range. It may be one that has been. In the latter case, all physical property values may be included in the above range.

The method for producing the cyclic olefin-based copolymer used in the present invention is not limited, but a catalyst containing the following compounds (A) and (B) as main components or the following compound (A),
It can be efficiently produced by copolymerizing the α-olefin and the cyclic olefin using a catalyst containing (B) and (C) as a main component. (A) Transition metal compound (B) Compound which reacts with transition metal compound to form an ionic complex (C) Organoaluminum compound

In this case, as the transition metal compound (A), there are IVB group, VB group, VIB group, VIIB group and VI of the periodic table.
Transition metal compounds containing transition metals belonging to Group II can be used. Specifically, titanium, zirconium, hafnium, chromium, manganese, nickel, palladium, platinum and the like are preferable as the above transition metal, and among them, zirconium, hafnium, titanium, nickel and palladium are preferable.

Examples of such a transition metal compound (A) include various compounds, but in particular, a compound containing a transition metal of IVB group or VIII group, especially a transition metal selected from IVB group of the periodic table, that is, A compound containing titanium (Ti), zirconium (Zr) or hafnium (Hf) can be preferably used, and particularly, a compound represented by the following general formula (I),
A cyclopentadienyl compound represented by (II) or (III) or a derivative thereof, or a compound represented by the following general formula (IV) or a derivative thereof is preferable. ^{_{CpM 1 R 1 a R 2 b}} R 3 c ... (I) Cp 2 M 1 R 1 a R 2 b ... (II) (Cp-A e -Cp) M 1 R 1 a R 2 b ... (III) M ¹ R ¹ _a R ² _b R ³ _c R ⁴ _d (IV)

[In the formulas (I) to (IV), M ¹ is Ti, Zr.
Or Hf atom, Cp is a cyclopentadienyl group,
A cyclic unsaturated hydrocarbon group or a chain unsaturated hydrocarbon group such as a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a tetrahydroindenyl group, a substituted tetrahydroindenyl group, a fluorenyl group or a substituted fluorenyl group is shown. R ¹ , R ² , R ³ and R ⁴ are each σ
A binding ligand, a chelating ligand, a ligand such as a Lewis base is shown, and specific examples of the σ binding ligand include a hydrogen atom, an oxygen atom, a halogen atom, and a carbon number of 1 to 1. 20 alkyl groups, 1-20 carbon alkoxy groups, 6 carbon atoms
Examples include 20 aryl groups, alkylaryl groups or arylalkyl groups, acyloxy groups having 1 to 20 carbon atoms, allyl groups, substituted allyl groups, substituents containing a silicon atom, and the like. Examples thereof include an acetylacetonate group and a substituted acetylacetonate group. A indicates crosslinking by covalent bond. a, b, c and d
Are integers of 0 to 4, respectively, and e is an integer of 0 to 6. R
Two or more of ¹ , R ² , R ³ and R ⁴ may combine with each other to form a ring. When Cp has a substituent, the substituent is preferably an alkyl group having 1 to 20 carbon atoms. In the formulas (II) and (III), the two Cp's may be the same or different from each other. ]

Examples of the substituted cyclopentadienyl group in the above formulas (I) to (III) include methylcyclopentadienyl group, ethylcyclopentadienyl group, isopropylcyclopentadienyl group, 1,2-dimethyl. Cyclopentadienyl group, tetramethylcyclopentadienyl group, 1,3-dimethylcyclopentadienyl group, 1,
2,3-trimethylcyclopentadienyl group, 1,2,
4-trimethylcyclopentadienyl group, pentamethylcyclopentadienyl group, trimethylsilylcyclopentadienyl group and the like can be mentioned. In addition, (I) ~ (I
Specific examples of R ^{1 to} R ^{4 in} the formula V) include, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom as a halogen atom; a methyl group, an ethyl group and n-propyl as an alkyl group having 1 to 20 carbon atoms. Group, iso-propyl group,
n-butyl group, octyl group, 2-ethylhexyl group; methoxy group, ethoxy group, propoxy group, butoxy group, phenoxy group as alkoxy group having 1 to 20 carbon atoms; aryl group having 6 to 20 carbon atoms, alkylaryl group or Phenyl group, tolyl group, xylyl group, benzyl group as an arylalkyl group; heptadecylcarbonyloxy group as an acyloxy group having 1 to 20 carbon atoms; trimethylsilyl group as a substituent containing a silicon atom, (trimethylsilyl) methyl group: Lewis base As dimethyl ether,
Ethers such as diethyl ether and tetrahydrofuran, thioethers such as tetrahydrothiophene, esters such as ethylbenzoate, nitriles such as acetonitrile and benzonitrile, trimethylamine, triethylamine, tributylamine, N, N-dimethylaniline, pyridine, 2, Amines such as 2'-bipyridine and phenanthroline; phosphines such as triethylphosphine and triphenylphosphine; ethylene, butadiene, 1-pentene, isoprene, pentadiene, 1-hexene and their derivatives as chain unsaturated hydrocarbons;
Examples of the cyclic unsaturated hydrocarbon include benzene, toluene, xylene, cycloheptatriene, cyclooctadiene, cyclooctatriene, cyclooctatetraene and derivatives thereof. Examples of the cross-linking by the covalent bond of A in the formula (III) include methylene cross-link, dimethyl methylene cross-link, ethylene cross-link,
Examples include cyclohexylene crosslinks, dimethylsilylene crosslinks, dimethylgermylene crosslinks, and dimethylstannylene crosslinks.

Examples of such compounds include the following compounds and compounds obtained by substituting zirconium of these compounds with titanium or hafnium. Compound of formula (I) (pentamethylcyclopentadienyl) trimethylzirconium, (pentamethylcyclopentadienyl) triphenylzirconium, (pentamethylcyclopentadienyl) tribenzylzirconium, (pentamethylcyclopentadienyl) trichloro Zirconium, (pentamethylcyclopentadienyl) trimethoxyzirconium, (cyclopentadienyl) trimethylzirconium, (cyclopentadienyl) triphenylzirconium, (cyclopentadienyl) tribenzylzirconium, (cyclopentadienyl) trichloro Zirconium, (cyclopentadienyl) trimethoxyzirconium, (cyclopentadienyl) dimethyl (methoxy) zirconium, (methylcyclopentadienyl) trimethyldi Ruconium, (methylcyclopentadienyl) triphenylzirconium, (methylcyclopentadienyl) tribenzylzirconium, (methylcyclopentadienyl) trichlorozirconium, (methylcyclopentadienyl) dimethyl (methoxy) zirconium,
(Dimethylcyclopentadienyl) trichlorozirconium, (trimethylcyclopentadienyl) trichlorozirconium, (trimethylsilylcyclopentadienyl) trimethylzirconium, (tetramethylcyclopentadienyl) trichlorozirconium,

A compound of formula (II) bis (cyclopentadienyl) dimethyl zirconium,
Bis (cyclopentadienyl) diphenylzirconium, bis (cyclopentadienyl) diethylzirconium, bis (cyclopentadienyl) dibenzylzirconium, bis (cyclopentadienyl) dimethoxyzirconium, bis (cyclopentadienyl) dichlorozirconium , Bis (cyclopentadienyl) dihydride zirconium, bis (cyclopentadienyl) monochloromonohydride zirconium, bis (methylcyclopentadienyl) dimethylzirconium, bis (methylcyclopentadienyl) dichlorozirconium, bis (methylcyclo Pentadienyl) dibenzylzirconium, bis (pentamethylcyclopentadienyl) dimethylzirconium, bis (pentamethylcyclopentadienyl) dichlorozirconium, Scan (pentamethylcyclopentadienyl) dibenzyl zirconium, bis (pentamethylcyclopentadienyl) chloromethyl zirconium,
Bis (pentamethylcyclopentadienyl) hydridomethylzirconium, (cyclopentadienyl) (pentamethylcyclopentadienyl) dichlorozirconium,

Compound of formula (III) ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) dichlorozirconium, ethylenebis (tetrahydroindenyl) dimethylzirconium, ethylenebis (tetrahydroindenyl) dichlorozirconium, dimethylsilylenebis (cyclo) Pentadienyl) dimethyl zirconium, dimethylsilylene bis (cyclopentadienyl) dichlorozirconium, isopropylidene (cyclopentadienyl) (9-fluorenyl) dimethylzirconium, isopropylidene (cyclopentadienyl) (9-fluorenyl) dichlorozirconium , [Phenyl (methyl) methylene] (9-fluorenyl) (cyclopentadienyl) dimethylzirconium, diphenylmethylene (cyclopen Tadienyl)
(9-fluorenyl) dimethylzirconium, ethylene (9-fluorenyl) (cyclopentadienyl) dimethylzirconium, cyclohexylidene (9-fluorenyl) (cyclopentadienyl) dimethylzirconium,
Cyclopentylidene (9-fluorenyl) (cyclopentadienyl) dimethylzirconium, cyclobutylidene (9-fluorenyl) (cyclopentadienyl) dimethylzirconium, dimethylsilylene (9-fluorenyl) (cyclopentadienyl) dimethylzirconium,
Dimethylsilylenebis (2,3,5-trimethylcyclopentadienyl) dichlorozirconium, dimethylsilylenebis (2,3,5-trimethylcyclopentadienyl) dimethylzirconium, dimethylsilylenebis (indenyl) dichlorozirconium

Examples of the compounds other than the cyclopentadienyl compounds represented by the above general formulas (I), (II) and (III) include the compounds of the above formula (IV). Examples thereof include a zirconium compound, a hafnium compound, and a titanium compound having one or more of an alkyl group, an alkoxy group, and a halogen atom, such as a compound in which zirconium is replaced with hafnium or titanium. Tetramethylzirconium, tetrabenzylzirconium, tetramethoxyzirconium, tetraethoxyzirconium, tetrabutoxyzirconium, tetrachlorozirconium, tetrabromozirconium,
Butoxytrichlorozirconium, dibutoxydichlorozirconium, bis (2,5-di-t-butylphenoxy) dimethylzirconium, bis (2,5-di-t-butylphenoxy) dichlorozirconium, zirconium bis (acetylacetonate),

The transition metal compound containing a VB to VIII group transition metal is not particularly limited, and specific examples of the chromium compound include tetramethylchromium and tetra (t).
-Butoxy) chromium, bis (cyclopentadienyl) chromium, hydridotricarbonyl (cyclopentadienyl) chromium, hexacarbonyl (cyclopentadienyl) chromium, bis (benzene) chromium, tricarbonyl tris (triphenylphosphonate) Examples thereof include chromium, tris (allyl) chromium, triphenyltris (tetrahydrofuran) chromium, chromium tris (acetylacetonate) and the like.

Specific examples of manganese compounds include tricarbonyl (cyclopentadienyl) manganese, pentacarbonylmethylmanganese, bis (cyclopentadienyl) manganese, manganese bis (acetylacetonate) and the like.

Specific examples of nickel compounds include, for example, dicarbonylbis (triphenylphosphine) nickel, dibromobis (triphenylphosphine) nickel, dinitrogen bis (bis (tricyclohexylphosphine) nickel), and chlorohydridobis (tricyclohexyl). Phosphine) nickel, chloro (phenyl) bis (triphenylphosphine) nickel, dimethylbis (trimethylphosphine) nickel, diethyl (2,
2'-bipyridyl) nickel, bis (allyl) nickel, bis (cyclopentadienyl) nickel, bis (methylcyclopentadienyl) nickel, bis (pentamethylcyclopentadienyl) nickel, allyl (cyclopentadienyl) Nickel, (cyclopentadienyl)
(Cyclooctadiene) nickel tetrafluoroborate, bis (cyclooctadiene) nickel, nickel bisacetylacetonate, allyl nickel chloride,
Tetrakis (triphenylphosphine) nickel, nickel _{chloride, (C 6 H 5) Ni} {OC (C 6 H 5) CH = P (C 6 H 5) 2} {P (C 6 H 5) 3}, ( _{C 6 H 5) Ni {OC} (C 6 H 5) C (SO 3 Na) = P (C 6 H 5) 2} {P (C 6 H 5) 3} and the like.

Specific examples of the palladium compound include dichlorobis (benzonitrile) palladium, carbonyltris (triphenylphosphine) palladium,
Dichlorobis (triethylphosphine) palladium, bis (t-butyl isocyanide) palladium, palladium bis (acetylacetonate), dichloro (tetraphenylcyclobutadiene) palladium, dichloro (1,5
-Cyclooctadiene) palladium, allyl (cyclopentadienyl) palladium, bis (allyl) palladium, allyl (1,5-cyclooctadiene) palladium tetrafluoroborate, (acetylacetonate)
Examples include (1,5-cyclooctadiene) palladium tetrafluoroborate, tetrakis (acetonitrile) palladium ditetrafluoroborate, and the like.

Any compound can be used as the compound (B) as long as it reacts with the transition metal compound (A) to form an ionic complex. A compound composed of a bound anion, particularly a coordination complex compound composed of a cation and an anion in which a plurality of groups are bonded to an element can be preferably used. The compound consisting of such a cation and an anion in which a plurality of groups are bound to an element is represented by the following formula (V) or (VI)
The compound represented by can be preferably used. ([L ¹ −R ⁷ ] ^{k +} ) _p ([M ³ Z ¹ Z ² … Z ⁿ ] ^(nm)- ) _q … (V) ([L ² ] ^{k +} ) _p ([M ⁴ Z ¹ Z ² …. Z ⁿ ] ^(nm)- ) _q (VI) (where L ² is M ⁵ , R ⁸ R ⁹ M ⁶ , R ¹⁰ ₃ C or R ¹¹ M ⁶ )

[In the formulas (V) and (VI), L ¹ is a Lewis base, M ³ and M ⁴ are VB group, VIB group and V of the periodic table, respectively.
IIB, VIII, IB, IIB, IIIA, IVA and
Elements selected from Group VA, preferably elements selected from Group IIIA, Group IVA and Group VA, M ⁵ and M ⁶ are Group IIIB, Group IVB, Group VB, Group VIB, Group VIB of the periodic table, respectively.
An element selected from Group III, Group IA, Group IB, Group IIA, Group IIB, and Group VIIA, Z ^{1 to} Z ⁿ are each a hydrogen atom, a dialkylamino group, an alkoxy group having 1 to 20 carbon atoms, and 6 to 20 carbon atoms. Aryloxy group, C1-C20 alkyl group, C6-C20 aryl group, alkylaryl group, arylalkyl group, C1-C20 halogen-substituted hydrocarbon group, C1-C20 acyloxy It represents a group, an organic metalloid group or a halogen atom, and two or more of Z ^{1 to} Z ⁿ may be bonded to each other to form a ring. R ⁷
Is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and a carbon number of 6 to
20 represents an aryl group, an alkylaryl group or an arylalkyl group, R ⁸ and R ⁹ are each a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group or a fluorenyl group, and R ¹⁰ is a C 1-20 group. An alkyl group, an aryl group, an alkylaryl group or an arylalkyl group is shown. R ¹¹ is tetraphenylporphyrin,
A macrocyclic ligand such as phthalocyanine is shown. m is M ³ , M
^{4 has} an valence of 1 to 7, n is an integer of 2 to 8, k is an ionic number of [L ¹ -R ⁷ ] and [L ² ] and is an integer of 1 to 7,
p is an integer of 1 or more, and q = (p × k) / (nm). ]

Specific examples of the Lewis base include ammonia, methylamine, aniline, dimethylamine, diethylamine, N-methylaniline, diphenylamine,
Amine such as trimethylamine, triethylamine, tri-n-butylamine, N, N-dimethylaniline, methyldiphenylamine, pyridine, p-promo-N, N-dimethylaniline, p-nitro-N, N-dimethylaniline, triethylphosphine Phosphines such as fin, triphenylphosphine and diphenylphosphine,
Examples thereof include ethers such as dimethyl ether, diethyl ether, tetrahydrofuran and dioxane, thioethers such as diethyl thioether and tetrahydrothiophene, and esters such as ethyl benzoate. Specific examples of M ³ and M ⁴ include B, Al, Si, P, As and Sb.
Etc., preferably B or P, and specific examples of M ⁵ are Li,
Specific examples of Na, Ag, Cu, Br, I, I _3, etc. and M ⁶ include Mn, Fe, Co, Ni, Zn and the like.

Specific examples of Z ^{1 to} Z ⁿ include, for example, a dimethylamino group and a diethylamino group as a dialkylamino group; a methoxy group, an ethoxy group, an n-butoxy group as an alkoxy group having 1 to 20 carbon atoms; and a carbon number of 6 A phenoxy group, a 2,6-dimethylphenoxy group, a naphthyloxy group as an aryloxy group of 20 to 20; a methyl group, an ethyl group, an n-propyl group as an alkyl group having 1 to 20 carbon atoms,
iso-propyl group, n-butyl group, n-octyl group,
2-ethylhexyl group; aryl group having 6 to 20 carbon atoms,
As an alkylaryl group or an arylalkyl group, a phenyl group, a p-tolyl group, a benzyl group, a 4-tert-butylphenyl group, a 2,6-dimethylphenyl group,
3,5-dimethylphenyl group, 2,4-dimethylphenyl group, 2,3-dimethylphenyl group; p-fluorophenyl group, 3,5-difluorophenyl group as a halogen-substituted hydrocarbon group having 1 to 20 carbon atoms, Pentachlorophenyl group, 3,4,5-trifluorophenyl group, pentafluorophenyl group, 3,5-di (trifluoromethyl) phenyl group; F, Cl, Br as halogen atoms
I: Examples of the organic metalloid group include pentamethylantimony group, trimethylsilyl group, trimethylgermyl group, diphenylarsine group, dicyclohexylantimony group and diphenylboron group. Specific examples of R ⁷ and R ¹⁰ include:
Examples are the same as those listed above. R ⁸ and R ⁹
Specific examples of the substituted cyclopentadienyl group include those substituted with an alkyl group such as a methylcyclopentadienyl group, a butylcyclopentadienyl group, and a pentamethylcyclopentadienyl group. Here, the alkyl group usually has 1 to 6 carbon atoms, and the number of substituted alkyl groups can be selected by an integer of 1 to 5. (V), (V
Among the compounds of formula I), those in which M ³ and M ⁴ are boron are preferred.

Among the compounds of the formulas (V) and (VI), the following can be used particularly preferably. Compound of formula (V) triethylammonium tetraphenylborate, tri (n-butyl) ammonium tetraphenylborate, trimethylammonium tetraphenylborate, tetraethylammonium tetraphenylborate, methyltri (n-butyl) ammonium tetraphenylborate, benzyltriphenylphenylborate (N-Butyl) ammonium, dimethyldiphenylammonium tetraphenylborate, methyltriphenylammonium tetraphenylborate, trimethylanilinium tetraphenylborate, methylpyridinium tetraphenylborate, benzylpyridinium tetraphenylborate, methyl tetraphenylborate (2-cyanopyridinium) ), Trimethylsulfonium tetraphenylborate, benzyldimethylsulfonium tetraphenylborate ,

Triethylammonium tetrakis (pentafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, triphenylammonium tetrakis (pentafluorophenyl) borate, tetrakis (pentafluorophenyl)
Tetrabutylammonium borate, tetrakis (pentafluorophenyl) borate (tetraethylammonium),
Tetrakis (pentafluorophenyl) borate (methyltri (n-butyl) ammonium), tetrakis (pentafluorophenyl) borate (benzyltri (n-butyl))
Ammonium), methyldiphenylammonium tetrakis (pentafluorophenyl) borate, methyltriphenylammonium tetrakis (pentafluorophenyl) borate, dimethyldiphenylammonium tetrakis (pentafluorophenyl) borate, anilinium tetrakis (pentafluorophenyl) borate, tetrakis (pentafluoro) (Phenyl) methylanilinium borate,
Dimethylanilinium tetrakis (pentafluorophenyl) borate, trimethylanilinium tetrakis (pentafluorophenyl) borate, dimethyl (m-nitroanilinium) tetrakis (pentafluorophenyl) borate, dimethyl tetrakis (pentafluorophenyl) borate (p-bromo) Anilinium),

Pyridinium tetrakis (pentafluorophenyl) borate, tetrakis (pentafluorophenyl) borate (p-cyanopyridinium), tetrakis (pentafluorophenyl) borate (N-methylpyridinium), tetrakis (pentafluorophenyl) borate (N
-Benzylpyridinium), tetrakis (pentafluorophenyl) borate (O-cyano-N-methylpyridinium), tetrakis (pentafluorophenyl) borate (p
-Cyano-N-methylpyridinium), tetrakis (pentafluorophenyl) borate (p-cyano-N-benzylpyridinium), tetrakis (pentafluorophenyl) borate trimethylsulfonium, tetrakis (pentafluorophenyl) borate benzyldimethylsulfonium, tetrakis ( Pentafluorophenyl) tetraphenylphosphonium borate, tetrakis (pentafluorophenyl) triphenylphosphonium borate, tetrakis (3,5-ditrifluoromethylphenyl) dimethylanilinium borate, triethylammonium hexafluoroarsenate,

Compound of Formula (VI) Ferrocenium tetraphenylborate, silver tetraphenylborate, trityl tetraphenylborate, tetraphenylborate (tetraphenylporphyrin manganese), ferrocenium tetrakis (pentafluorophenyl) borate, tetrakis (pentafluorophenyl) borate (1,1'-
Dimethylferrocenium), tetrakis (pentafluorophenyl) borate decamethylferrocenium, tetrakis (pentafluorophenyl) borate acetylferrocenium, tetrakis (pentafluorophenyl) borate formylferrocenium, tetrakis (pentafluorophenyl) borate Cyanoferrocenium, silver tetrakis (pentafluorophenyl) borate, trityl tetrakis (pentafluorophenyl) borate, lithium tetrakis (pentafluorophenyl) borate, sodium tetrakis (pentafluorophenyl) borate, tetrakis (pentafluorophenyl) borate (tetra Phenylporphyrin manganese), tetrakis (pentafluorophenyl) boric acid (tetraphenylporphyrin iron chloride), tetrakis (pentafluoro) Phenyl) borate (tetraphenylporphyrin zinc), silver tetrafluoroborate, hexafluoroarsenate, silver hexafluoroantimonate, silver

Compounds other than those represented by formulas (V) and (VI), such as tri (pentafluorophenyl) boron, tri (3,3)
5-di (trifluoromethyl) phenyl) boron, triphenylboron and the like can also be used.

Examples of the organoaluminum compound as the component (C) include those represented by the following general formula (VII), (VIII) or (IX). R ¹² _r AlQ _3-r (VII) (R ¹² is a hydrocarbon group such as an alkyl group, an alkenyl group, an aryl group or an arylalkyl group having 1 to 20 carbon atoms, preferably 1 to ¹² carbon atoms, Q is a hydrogen atom, It represents an alkoxy group having 1 to 20 carbon atoms or a halogen atom, and r is in the range of 1 ≦ r ≦ 3. Examples of the compound of the formula (VII) include trimethylaluminum, triethylaluminum and triisopropyl. Aluminum, triisobutyl aluminum, dimethyl aluminum chloride, diethyl aluminum chloride, methyl aluminum dichloride, ethyl aluminum dichloride, dimethyl aluminum fluoride, diisobutyl aluminum hydride, diethyl aluminum hydride, ethyl aluminum sesquichloride and the like can be mentioned.

[0047]

[Chemical 3] (R < ¹² > shows the same thing as a formula (VII). S shows a polymerization degree and is 3-50 normally, Preferably it is 7-40.) The chain | strand-shaped aluminoxane shown by these.

[0048]

[Chemical 4] (R ¹² represents the same as in formula (VII), s represents the degree of polymerization, and the preferred number of repeating units is 3 to 50, preferably 7 to 40.) Cyclic alkyl having a repeating unit Aluminoxane. Among the compounds represented by the formulas (VII) to (IX), an alkyl group-containing aluminum compound or aluminoxane having at least one alkyl group having 3 or more carbon atoms, and particularly having at least one branched alkyl group is preferable. Particularly preferred is triisobutylaluminum or aluminoxane having a degree of polymerization of 7 or more. When this triisobutylaluminum, aluminoxane having a degree of polymerization of 7 or more, or a mixture thereof is used, high activity can be obtained. Further, a modified aluminoxane which is insoluble in an ordinary solvent obtained by modifying the aluminoxane represented by the formulas (VIII) to (IX) with a compound having active hydrogen such as water is also preferably used.

As a method for producing the aluminoxane, there may be mentioned a method in which an alkylaluminum and a condensing agent such as water are brought into contact with each other, but the means therefor is not particularly limited, and the reaction may be carried out according to a known method. For example, a method in which an organoaluminum compound is dissolved in an organic solvent and brought into contact with water, a method in which an organoaluminum compound is initially added at the time of polymerization, and water is added later, water of crystallization contained in a metal salt, etc. There are a method of reacting water adsorbed on an inorganic substance or an organic substance with an organoaluminum compound, a method of reacting a tetraalkyldialuminoxane with a trialkylaluminum, and further reacting with water.

The catalyst used in the production of the olefinic copolymer of the present invention comprises the above-mentioned components (A) and (B) or (A),
The components (B) and (C) are the main components. In this case, the use conditions of the component (A) and the component (B) are not limited, but the ratio (molar ratio) of the component (A) to the component (B) is 1:
It is preferably 0.01 to 1: 100, particularly 1: 0.5 to 1:10, and particularly preferably 1: 1 to 1: 5. The operating temperature is preferably in the range of -100 to 250 ° C, and the pressure and time can be set arbitrarily.

The amount of the component (C) used is usually 0 to 2,000 mol, preferably 5 to 1 mol of the component (A).
The amount is 1,000 mol, particularly preferably 10 to 500 mol. When the component (C) is used, the polymerization activity can be improved, but if it is too much, a large amount of the organoaluminum compound remains in the polymer, which is not preferable.

The mode of use of the catalyst component is not limited, and for example, the components (A) and (B) may be contacted in advance, or the contact product may be separated and washed before use. You may use it by making a contact. Further, the component (C) may be used by being brought into contact with the contact product of the component (A), the component (B) or the component (A) and the component (B) in advance.
The contact may be made in advance or in the polymerization system. Further, the catalyst component can be added to the monomer or the polymerization solvent in advance, or can be added to the polymerization system. The catalyst component can be used by supporting it on an inorganic or organic carrier, if necessary.

The ratio of the catalyst to the reaction raw material is 1 to 10 ^{9 of} raw material monomer / component (A) (molar ratio) or raw material monomer / component (B) (molar ratio), especially 1
It is preferably from 00 to 10 ⁷ .

Polymerization methods include bulk polymerization, solution polymerization,
Any method such as suspension polymerization or gas phase polymerization may be used.
Further, a batch method or a continuous method may be used. When a polymerization solvent is used, for example, aromatic hydrocarbons such as benzene, toluene, xylene and ethylbenzene, alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclohexane,
Aliphatic hydrocarbons such as pentane, hexane, heptane and octane, halogenated hydrocarbons such as chloroform and dichloromethane can be used. These solvents may be used alone or in combination of two or more. Further, a monomer such as α-olefin may be used as a solvent.

Regarding the polymerization conditions, the polymerization temperature is -100 to 2
The temperature is preferably 50 ° C, particularly preferably -50 to 200 ° C.
The polymerization time is usually 1 minute to 10 hours, and the reaction pressure is atmospheric pressure to 10
0 Kg / cm ² G, preferably normal pressure to 50 Kg / cm ² G
Is. The method for controlling the molecular weight of the copolymer can be selected by the amount of each catalyst component used, the polymerization temperature, and the polymerization reaction in the presence of hydrogen.

The infusion solution bag of the present invention comprises a film in which at least the innermost layer is formed of the cyclic olefin copolymer layer having excellent chemical resistance and thermal stability. In this case, the cyclic olefin-based copolymer layer is an α-olefin / cyclic olefin copolymer composed of an α-olefin and a cyclic olefin, or a mixture of this and a cyclic diene,
Α-Olefin copolymerized with dienes such as cyclic dienes
It can be formed of a cyclic olefin / diene copolymer, a crosslinked product of the above with thermal crosslinking, radiation crosslinking, or the like. When the crosslinked product is used, the heat resistance of the cyclic olefin-based copolymer layer is improved. Examples of the cross-linking agent used for cross-linking the cross-linked product include the commonly used organic peroxides and diazo compounds. Specifically, benzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, tert-butyl cumyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, azobisisobutyronitrile and the like. .. The amount of the crosslinking agent used is 0.01 with respect to the copolymer.
It is at least wt%, preferably 0.03 to 1 wt%.

The structure of the film forming the infusion bag of the present invention is not limited, and a single layer film made of the cyclic olefin copolymer may be used, and the innermost layer made of the cyclic olefin copolymer may be used. You may use the multilayer film which has. In the latter case, layers other than the innermost layer are preferably formed of a resin having higher heat resistance than the cyclic olefin-based copolymer, for example, propylene / ethylene copolymer, whereby an infusion bag having excellent heat resistance is obtained. be able to.

The infusion bag of the present invention can be manufactured by a commonly used bag-making method, and can be formed into any shape and size according to the purpose of use. As the bag-making method, for example, a method of forming a single layer or a multilayer film having a cyclic olefin-based copolymer layer and making a bag from this film, a method of making a bag by blow molding, and the like can be adopted. When the bag is made from the film, the films may be overlapped, the periphery thereof may be heat-sealed into a predetermined shape to make the bag, and then the plug member obtained by injection molding of polyethylene or polypropylene may be attached by heat-sealing.

[0059]

EXAMPLES Next, the present invention will be specifically shown by Examples and Comparative Examples, but the present invention is not limited to the following Examples. First, prior to the production of a medical infusion bag, a cyclic olefin-based copolymer of the following reference example was produced.

Reference Example 1 (Copolymerization of Ethylene and 2-Norbornene) Under a nitrogen atmosphere, at room temperature, 15 liters of toluene, 23 mmol of triisobutylaluminum (TIBA), 110 micromoles of zirconium tetrachloride and tetra tetrachloride were added to a 30 liter autoclave. 150 μmol of anilinium (pentafluorophenyl) borate was added in this order, followed by 2.3 liters of a toluene solution containing 70% by weight of 2-norbornene (1 as 2-norbornene).
5 mol) was added. After the temperature was raised to 90 ° C., the reaction was carried out for 110 minutes while continuously introducing ethylene so that the ethylene partial pressure became 7 kg / cm ² . After the reaction was completed, the polymer solution was poured into 15 liters of methanol to precipitate the polymer. This polymer was collected by filtration and dried to obtain a cyclic olefin-based copolymer (a1). The yield of the cyclic olefin-based copolymer (a1) was 3.89 Kg.
The polymerization activity was 388 Kg / gZr.

The resulting cyclic olefin copolymer (a
The physical properties of 1) were as follows. 30 of ¹³ C-NMR
The sum of the peaks based on ethylene and the peaks based on methylene at the 5th and 6th positions of norbornene appearing around ppm and 3
The norbornene content calculated from the ratio with the peak based on the methylene group at the 7-position of norbornene appearing at around 2.5 ppm was 9.2 mol%. The intrinsic viscosity [η] measured in decalin at 135 ° C. was 0.99 dl / g, and the crystallinity determined by X-ray diffractometry was 1.0%. Vibron 11-EA manufactured by Toyo Boulding Co., Ltd. is used as a measuring device, and a measuring piece having a width of 4 mm, a length of 40 mm and a thickness of 0.1 mm is measured at a heating rate of 3 ° C./min and a frequency of 3.5 Hz. The glass transition temperature (Tg) was determined from the peak of the loss elastic modulus (E ″) of Tg was 3 ° C. ALC / GPC150C manufactured by Waters was used as a measuring device, and 1,2,4-trichlorobenzene solvent was used. , 135 ° C
Then, when the weight average molecular weight Mw, the number average molecular weight Mn, and the molecular weight distribution (Mw / Mn) were calculated in terms of polyethylene,
Mw is 54,200, Mn is 28,400, Mw / Mn
= 1.91. Perkin Elmer 7 series DSC at a temperature rising rate of 10 ° C./min.
The melting point (Tm) was measured in the range of 150 ° C.
Was 72 ° C. (broad peak).

Reference Example 2 (Copolymerization of Ethylene and 2-Norbornene) Under a nitrogen atmosphere at room temperature, 15 liters of toluene, 23 mmol of triisobutylaluminum (TIBA), 38 micromoles of zirconium tetrachloride and tetra tetrafluoroethylene were added to a 30 liter autoclave. (Pentafluorophenyl)
Add 60 micromoles of anilinium borate in this order,
Subsequently, 2.4 liters of a toluene solution containing 70% by weight of 2-norbornene (16 mol of 2-norbornene) was added. After heating to 80 ° C, the ethylene partial pressure is 8
The reaction was carried out for 110 minutes while continuously introducing ethylene so as to obtain Kg / cm ² . After the reaction was completed, the polymer solution was poured into 15 liters of methanol to precipitate the polymer. This polymer was collected by filtration and dried to obtain a cyclic olefin copolymer (a2). The yield of the cyclic olefin-based copolymer (a2) was 2.93 Kg. The polymerization activity was 845 Kg / gZr.

The physical properties of the cycloolefin copolymer (a2) obtained in the same manner as above were as follows. Norbornene content is 7.7 mol%, intrinsic viscosity [η] is 1.20
dl / g, crystallinity 1.0%, Tg 0 ° C., Mw 6
9,600, Mn is 35,900, and Mw / Mn is 1.9.
4, Tm was 72 ° C. (broad peak).

Evaluation of heat resistance Cyclic olefin copolymers a1 and a obtained in Reference Example
2. Using high-density polyethylene and linear low-density polyethylene, the same resin is repeated 1 to 5 times at a resin temperature of 160 ° C. in an extruder with a diameter of 30 mm to pelletize,
The melt index (MI) of the pellets obtained at each pelletization was measured. MI and 1 before pelletizing
MI retention after the first and subsequent pelletizations [(MI after pelletization / MI before pelletization) × 100
(%)] Is shown in Table 1. MI is JI at 190 ℃
It measured according to S-7210.

[0065]

[Table 1]

Next, examples using the cyclic olefin-based copolymers obtained in the above reference examples will be shown. Example A film having a thickness of 140 μ and formed of the cyclic olefin copolymers (a1 and a2) obtained in Reference Example was molded. Next, the films were overlapped and heat-sealed on four sides to form a bag of 150 mm × 200 mm. Finally, a polypropylene plug member was attached to this bag by heat sealing to obtain a medical infusion bag of the present invention.

As described above, the medical infusion bag of the present invention has high thermal stability without adding a stabilizer,
And because it uses a resin with excellent heat sealability, melt flowability, and liquid resistance, problems such as elution of additives do not occur, and since it has elasticity (recovery),
It is useful as a medical member without the risk of bag breakage.

Claims (1)

[Claims] 1. A cyclic olefin-based copolymer having a repeating unit derived from an α-olefin and a repeating unit derived from a cyclic olefin and having a glass transition temperature (Tg) of 70 ° C. or lower to form at least an inner layer. A medical infusion bag characterized in that