WO2013172235A1

WO2013172235A1 - Multilayer film, drug solution container and process for production thereof

Info

Publication number: WO2013172235A1
Application number: PCT/JP2013/062958
Authority: WO
Inventors: 浩二鈴江; 正臣川井; 裕信松尾
Original assignee: 大塚テクノ株式会社; 南京大塚泰邦科技有限公司
Priority date: 2012-05-15
Filing date: 2013-05-08
Publication date: 2013-11-21
Also published as: CN104520103B; CN104520103A; IN2014DN09629A; JPWO2013172235A1; JP6106891B2

Abstract

This multilayer film has a laminate structure comprising at least three layers, namely, an innermost layer, an outermost layer and an intermediate layer therebetween, wherein the innermost layer comprises a mixture which comprises 40 to 80wt% of a composite polypropylene-based resin that contains at least two polypropylene-based resins having melting points different from each other and 60 to 20wt% of a thermoplastic elastomer (E). The two polypropylene-based resins comprise (A) a random copolymer that has a relatively low melting point and that is obtained by polymerization in the presence of a metallocene catalyst and (B) a random copolymer that has a melting point higher than that of the random copolymer (A).

Description

Multilayer film, chemical container, and method for producing the same

The present invention relates to a multilayer film suitable for use in a container for containing a chemical solution such as an infusion, a chemical solution container using the multilayer film, and a method for producing the same.

Conventionally, a container for a pharmaceutical solution formed by heat-sealing a sheet containing a plurality of polypropylene resins is known.

For example, Patent Document 1 heat seals a sheet containing 60% by weight of syndiotactic polypropylene, 15% by weight of an isotactic / ethylene / propylene random copolymer, and 25% by weight of an ethylene / propylene copolymer rubber. A container for a pharmaceutical solution formed by the above is disclosed.

JP 7-178150 A

The manufacturing process of the chemical container includes a process of forming a bag by heat-sealing the overlapping plastic films and a process of punching the bag from the film. Generally, heat sealing and punching of bags are performed in separate processes, but from the viewpoint of improving production efficiency and simplifying the equipment, punching heat sealing methods that perform these processes simultaneously are widely used throughout the world. ing.

When adopting the punching heat sealing method, a die having a flat surface is used as the lower die for heat sealing. Since the surface of the lower mold (flat surface) contacts the entire bag during heat sealing, the heat during sealing is also transmitted to the part filled with the chemical (container chamber) and the inner surfaces of the storage chamber stick to each other, making it as light as possible Pseudo-seal that is heat-sealed is likely to occur. Since the pseudo-seal prevents the chemical solution from being filled in the storage chamber, it is preferably not generated or suppressed to a low peel strength even if it is generated.

However, it is very difficult to prevent the occurrence of a pseudo seal in the punching heat seal method. Because, in order to produce a container by the punching heat seal method, it is necessary to form a film with a resin having a relatively low melting point, and to perform heat sealing at a low temperature and in a short time, but using a low melting point resin, This is because the frequency of occurrence of pseudo seals increases.

In addition, since generally used polypropylene is a relatively hard resin, there is a problem that it is difficult to impart excellent strength to a conventional polypropylene liquid chemical container.

Therefore, the object of the present invention is to achieve both prevention of pseudo-seal generation or reduction of peel strength and improvement of bag production efficiency, and excellent strength (drop resistance, pressure resistance) when formed into a bag shape. ), A chemical solution container using the multilayer film, and a method for producing the same.

In order to achieve the above object, the multilayer film of the present invention comprises a laminated structure of at least three layers of an innermost layer, an outermost layer and an intermediate layer therebetween, and the innermost layer comprises at least two types of polypropylene having different melting points. Composed of a mixture of 40 to 80% by weight of a composite polypropylene resin containing a thermoplastic resin and 60 to 20% by weight of a thermoplastic elastomer (E). The two types of polypropylene resins have a relatively low melting point and are metallocene-based. A random copolymer (A) obtained by polymerization in the presence of a catalyst; and a random copolymer (B) having a relatively higher melting point than the random copolymer (A).

In the multilayer film of the present invention, the random copolymer (A) is a resin having a melting point of 110 ° C. to 135 ° C., and the random copolymer (B) is a resin having a melting point of 140 ° C. to 160 ° C. It is preferable.

In the multilayer film of the present invention, the ratio of the random copolymer (A) to 100 parts by weight of the composite polypropylene resin is preferably 35 to 85 parts by weight.

In the multilayer film of the present invention, the thermoplastic elastomer (E) preferably contains an elastomer (C) having a tensile strength of 20 MPa or more and a glass transition temperature of −35 ° C. or less.

In the multilayer film of the present invention, the elastomer (C) is preferably a styrene elastomer.

The chemical liquid container of the present invention is a bag body in which the peripheral edges of a pair of the multilayer films of the present invention overlapped so that the innermost layers face each other are heat-sealed, and a storage chamber for storing the chemical liquid is defined inside, And a spout for pouring out the chemical from the bag body.

In the chemical solution container of the present invention, the chemical solution container filled with the liquid is sterilized at 121 ° C. for 15 minutes, and a 6.4 kg iron plate is dropped into the sterilized chemical solution container, and the chemical solution container is broken. It is preferable that the falling plate strength expressed as the maximum drop height at which no bag or liquid leakage occurs is 40 cm or more.

In the chemical container of the present invention, the bag main body is formed by adhering the inner surfaces of the storage chambers to each other, has a pseudo-seal with a peel strength of less than 2N, and the chemical solution container supplies liquid to the storage chamber. It is preferable that the filled chemical solution container is sterilized at 121 ° C. for 15 minutes, and the internal pressure of the sterilized chemical solution container is increased to 200 kPa, and then has a strength capable of withstanding constant pressurization for 15 minutes.

The chemical solution container of the present invention preferably further includes a chemical solution filled in the storage chamber.

The method for producing a chemical container of the present invention comprises a step of superposing a pair of multilayer films of the present invention so that the innermost layers face each other, a pair of multilayer films, a lower mold having a flat surface, and a surface A bag body in which a storage chamber for storing a chemical solution is defined by sandwiching between a pair of multilayer films and forming a heat seal on the periphery of the pair of multilayer films. And simultaneously punching the bag body from the other part of the pair of multilayer films.

According to the multilayer film of the present invention, the innermost layer is composed of a mixture of 40 to 80% by weight of the composite polypropylene resin and 60 to 20% by weight of the thermoplastic elastomer (E), and the composite polypropylene resin has a relatively low content. The random copolymer (A) on the melting point side is balanced with the random copolymer (B) on the relatively high melting point side, and the melting point is adjusted so as not to generate a pseudo seal. Therefore, even when the bag body is formed by sandwiching between a lower mold having a flat surface and an upper mold having a concave portion formed on the surface as in the manufacturing method of the present invention, a pseudo seal is generated. Even if it does not occur or occurs, the peel strength can be lowered. In addition, heat sealing can be performed at a low temperature in a short time, and production efficiency can be improved. And according to the chemical | medical solution container using the multilayer film of this invention, the outstanding intensity | strength (drop resistance, pressure resistance) can be expressed.

FIG. 1 is a schematic configuration diagram of a chemical solution bag according to an embodiment of the present invention. 2 (a) and 2 (b) are cross-sectional views taken along section line II-II in FIG. 1. FIG. 2 (a) shows a state before filling with a chemical solution, and FIG. 2 (b) shows a state after filling with the chemical solution. Each is shown. FIGS. 3 (a) and 3 (b) are views showing a part of the method for manufacturing the chemical solution bag, wherein FIG. 3 (a) is a plan view and FIG. 3 (b) is viewed from a cutting plane line IIIb-IIIb. It is sectional drawing. 4 (a) and 4 (b) are diagrams showing steps subsequent to FIGS. 3 (a) and 3 (b), in which FIG. 4 (a) is a plan view and FIG. 4 (b) is a section line IVb-IVb. It is sectional drawing seen from.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
<Overall configuration of chemical bag>
FIG. 1 is a schematic configuration diagram of a chemical solution bag according to an embodiment of the present invention. 2 (a) and 2 (b) are cross-sectional views taken along section line II-II in FIG. 1. FIG. 2 (a) shows a state before filling with a chemical solution, and FIG. Each is shown.

The chemical solution bag 1 as a chemical solution container is a single-chamber bag having one room (accommodating chamber 2) for accommodating a chemical solution (for example, medical solution such as infusion and blood). The chemical solution bag 1 includes a bag main body 3 in which a storage chamber 2 is partitioned, and a pouring member 4 as a spout for pouring out the chemical solution from the bag main body 3.

As shown in FIGS. 2A and 2B, the bag body 3 is formed into a flat rectangular (rectangular) bag shape by heat-sealing the periphery of two overlapping (a pair of) multilayer films 5. ing. A hollow portion partitioned by the heat seal 6 is the storage chamber 2.

As shown in FIG. 2A, the bag body 3 may have a pseudo seal 7 formed by adhering the inner surfaces of the storage chamber 2 to each other in a state before being filled with the chemical solution. The pseudo seal 7 is different from the heat seal 6 in which the multilayer film 5 is selectively melted and bonded so that the films are not peeled off. Specifically, the pseudo seal 7 is a portion in which the films are adhered to each other by heat transmitted to one or both of the multilayer films 5 in the manufacturing process of the chemical solution bag 1 and appear to be lightly heat sealed. is there. Therefore, the peel strength of the pseudo seal 7 is very low compared to the heat seal 6. In this embodiment, the peel strength of the pseudo seal 7 is less than 2N, preferably 0N (no pseudo seal 7) to 1N. If the peel strength of the pseudo seal 7 is within this range, the pseudo seal 7 can be peeled only by the pressure of the chemical solution 8 when the chemical solution 8 is filled in the storage chamber 2 as shown in FIG. Therefore, the work of peeling the pseudo seal 7 before filling with the chemical solution 8 can be omitted, so that the production efficiency of the chemical solution bag 1 can be improved.

Further, the length L of the bag body 3 is, for example, 150 to 350 mm, and the width W is, for example, 100 to 250 mm. The capacity of the chemical solution bag 1 (the storage chamber 2) is, for example, 100 to 1000 mL.

The multilayer film 5 that forms the bag body 3 has a three-layer laminated structure of an innermost layer 51, an outermost layer 53, and an intermediate layer 52 therebetween, as shown in FIGS. The thicknesses of the layers 51 to 53 are preferably, for example, that the innermost layer 51 is 20 μm to 50 μm, the intermediate layer 52 is 105 μm to 170 μm, and the outermost layer 53 is 15 μm to 30 μm. The total thickness of the multilayer film 5 is preferably 150 μm to 250 μm, for example. In addition, since the multilayer film 5 has no distinction between the front and back when viewed alone, the innermost layer 51, the intermediate layer 52, and the outermost layer 53 are the first layer (the innermost layer 51) and the second layer (the intermediate layer 52), respectively. And the third layer (outermost layer 53).

The innermost layer 51 is made of a mixture of a composite polypropylene resin and a thermoplastic elastomer (E). The weight ratio of the mixture is 40 to 80% by weight, preferably 50 to 70% by weight, for the composite polypropylene resin. The thermoplastic elastomer (E) is 60 to 20% by weight, preferably 50 to 30% by weight.

The composite polypropylene resin includes at least two types of polypropylene resins having different melting points. That is, the composite polypropylene resin has a random copolymer (A) having a relatively low melting point (polypropylene random copolymer (A)) and a random having a relatively higher melting point than the random copolymer (A). It contains at least two types of copolymer (B) (polypropylene random copolymer (B)), and may further contain other types of polypropylene resins as necessary.

In common with all the propylene resins contained in the composite polypropylene resin, the propylene resin is, for example, a homopolymer such as isotactic homopolypropylene or syndiotactic homopolypropylene, or a copolymer containing a comonomer. There may be.

Examples of the comonomer other than propylene in the copolymer include α-olefins such as ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. Preferably, ethylene is used. Further, the form of the copolymer may be either a random copolymer or a block copolymer.

In the present invention, among these, it is preferable to use a random copolymer as the propylene resin contained in the composite polypropylene resin. In particular, for at least two types of polypropylene resins having different melting points, the random copolymer (A) is a resin having a melting point of 110 ° C. to 135 ° C., and the random copolymer (B) is 140 ° C. to 160 ° C. A resin having a melting point of The random copolymer (A) can be obtained by copolymerizing a propylene monomer and a comonomer other than propylene (preferably ethylene) under a predetermined condition in the presence of a metallocene catalyst.

The random copolymer (A) is contained in an amount of 35 to 85 parts by weight, preferably 45 to 70 parts by weight, based on 100 parts by weight of the composite polypropylene resin. On the other hand, the random copolymer (B) is contained in an amount of 65 to 15 parts by weight, preferably 55 to 30 parts by weight, with respect to 100 parts by weight of the composite polypropylene resin.

The thermoplastic elastomer (E) contained in the innermost layer 51 may be various thermoplastic elastomers such as a styrene elastomer, an olefin elastomer, a urethane elastomer, and an ester elastomer. These can be used alone or in combination of two or more. In the present invention, among these, the innermost layer 51 preferably contains a styrene elastomer, and more preferably contains a mixture of a styrene elastomer and an olefin elastomer. The weight ratio of the mixture is, for example, 20 to 50% by weight for the styrene elastomer and 0 to 30% by weight for the olefin elastomer. The thermoplastic elastomer (E) preferably has a tensile strength of 20 MPa or more and a glass transition temperature of −35 ° C. or less as a whole.

The resin constituting the intermediate layer 52 and the outermost layer 53 is not particularly limited, and a known resin can be applied. For example, polyolefin resins such as polyethylene, polypropylene, poly (4-methylpentene), polytetrafluoroethylene, polycyclic olefin resins such as ethylene-tetracyclododecene, polyester resins such as polyethylene terephthalate (PET), ethylene -Vinyl acetate copolymer (EVA), ethylene-vinyl alcohol copolymer (EVOH), vinyl polymer resins such as polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride, nylon-6, nylon-12, nylon-6 General purpose resins such as polyamide resins such as No.6 and No.6. These may be used alone or in combination of two or more.

The annular heat seal 6 that divides the storage chamber 2 includes a pair of vertical seals 9 that seal the opposing long sides of the storage chamber 2, and a pair of horizontal seals 10 that seal the opposing short sides of the storage chamber 2. Are integrally included. The pair of vertical seals 9 both have the same constant width and extend vertically in parallel with a straight line. The pair of horizontal seals 10 includes a head side seal 101 that seals the short side on the side where the dispensing member 4 is disposed, and a bottom side seal that seals the short side on the opposite side (bottom side) of the storage chamber 2 to the head side. 102.

The head-side seal 101 extends laterally with a wider seal width than the vertical seal 9, and the extraction member 4 is fixed at the center in the length direction.

The bottom-side seal 102 has a wider seal width than the vertical seal 9 and extends in parallel to the head-side seal 101, and a suspension hole 12 is formed at the center in the length direction. The bottom-side seal 102 is provided with one non-sealing portion 13 that is not heat-sealed on both sides in the lateral direction across the suspension hole 12.

The dispensing member 4 includes a base member 41 that is fixed to the bag body 3 and a nozzle 42. The base member 41 is a boat-type port having a rhombus shape as viewed from the dispensing direction, and is made of, for example, plastic such as polypropylene or polyethylene. The base member 41 is fixed to the bag body 3 in close contact with the multilayer film 5 by being heat sealed while being sandwiched between the two multilayer films 5 when the bag body 3 is manufactured. The nozzle 42 is made of the same material as the base member 41, and is formed integrally with the base member 41, for example. As shown by a broken line in FIG. 1, for example, a pull-top type cap 43 is attached to the nozzle 42 by heat welding or the like.
<Method for manufacturing chemical solution bag>
3 and 4 are diagrams for explaining a part of the manufacturing method of the chemical solution bag 1 in the order of steps. 3 and 4, each multilayer film 5 is represented by a single layer structure for the sake of clarity.

In order to manufacture the medical solution bag 1, for example, as shown in FIGS. 3A and 3B, the two multilayer films 5 are overlapped so that the innermost layers 51 face each other (see FIG. 2A). .

Next, as shown in FIGS. 4A and 4B, a lower mold 14 and an upper mold 15 for applying the heat seal 6 are prepared.

The lower mold 14 has a flat surface 14A, and can support the entire surface of the multilayer film 5 on the outermost layer 53 (third layer) side during heat sealing. On the other hand, the upper mold 15 is selectively formed on the surface 15A thereof with a linear seal surface extending in the longitudinal direction with the same constant width as that of the vertical seal 9, and a portion other than the seal surface of the surface 15A is A recess 16 is formed for securing the storage chamber 2 of the bag body 3 during heat sealing.

Then, the upper and

lower molds

15 and 14 are formed from both sides in the thickness direction so that the two laminated multilayer films 5 are brought into contact with the surface 14A of the lower mold 14 so that the seal surface 15A of the upper mold 15 contacts the surface 14A. The lower mold 14 and the upper mold 15 are both heated while being sandwiched. For example, the temperature of the lower mold 14 is preferably 100 ° C. to 150 ° C., and the temperature of the upper mold 15 is preferably 130 ° C. to 170 ° C. The welding pressure is preferably 1.0 MPa to 5.0 MPa, and the welding time is preferably 0.5 seconds to 2.0 seconds. Thereby, the heat seal 6 of the chemical solution bags 1 for a plurality of parts is simultaneously applied to the multilayer film 5. At this time, since the surface 14A of the lower mold 14 is in contact with the whole chemical solution bag 1, heat at the time of sealing is also transmitted to the storage chamber 2 so that the inner surfaces of the storage chamber stick to each other and the pseudo seal 7 is generated. is there. However, in the present invention, since the innermost layer 51 is made of the resin having the composition described above, the peel strength of the pseudo seal 7 can be less than 2N. In the present invention, simultaneously with this heat sealing step, the unnecessary multi-layer film 5 is cut to punch out the individual drug solution bags 1 at a time. Thereafter, the dispensing member 4 is attached to each chemical solution bag 1 by heat sealing. Thereby, the chemical | medical solution bag 1 of FIG. 1 is obtained.
<Operational effects of this embodiment>
As described above, according to the multilayer film 5, the innermost layer 51 is composed of a mixture of 40 to 80% by weight of the composite polypropylene resin and 60 to 20% by weight of the thermoplastic elastomer (E). In particular, the random copolymer (A) on the low melting point side and the random copolymer (B) on the relatively high melting point side are balanced, and the melting point is adjusted so as not to generate a pseudo seal. Therefore, as shown in FIGS. 4A and 4B, the bag body 3 is sandwiched between a lower mold 14 having a flat surface 14A and an upper mold 15 having a concave portion 16 having a predetermined shape formed on the surface 15A. Even when formed, the pseudo seal 7 is not generated, or even if it is generated, the peel strength can be less than 2N. In addition, the heat sealing process shown in FIGS. 4A and 4B can be performed at a low temperature and in a short time, and the production efficiency can be improved. And according to the chemical | medical solution bag 1 using the multilayer film 5, the outstanding intensity | strength (drop resistance, pressure | voltage resistance) can be expressed.

Specifically, regarding the drop resistance, the chemical solution bag 1 (see FIG. 2 (b)) filled with the chemical solution 8 in the storage chamber 2 is sterilized at 121 ° C. for 15 minutes. By dropping a 4 kg iron plate, the falling plate strength expressed as the maximum drop height at which the chemical bag 1 does not break or leak can be made 40 cm or more.

Moreover, regarding the pressure resistance, the prepared sample can be sterilized at 121 ° C. for 15 minutes, and after the internal pressure after sterilization is increased to 200 kPa, the strength to withstand a constant pressure for 15 minutes can be imparted.

Moreover, the chemical solution bag 1 may be sterilized after filling the container 2 with the chemical solution. Examples of the sterilization process to be applied include known heat sterilization processes such as high-pressure steam sterilization and hot water shower sterilization. The processing temperature of these heat sterilization treatments may be set to about 105 ° C. to 110 ° C. or 118 ° C. to 121 ° C. in accordance with the type of chemical solution, usage, use environment, and the like. Since the medical solution bag 1 is formed using the multilayer film 5 of the present invention, the heat resistance against high temperature sterilization is excellent. Therefore, even when the chemical solution bag 1 is subjected to high temperature sterilization at 118 ° C. to 121 ° C., moderate flexibility and good transparency can be maintained.

Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

For example, the bag body 3 does not necessarily have to be a superposition of two multilayer films 5, and the single multilayer film 5 is formed into a bag shape or a tube shape by a known method such as an inflation method. It may be overlapped so as to form a pair. In that case, the bag main body 3 can be produced by heat-sealing the periphery of the bag-shaped or tube-shaped multilayer film 5.

In the above-described embodiment, only a three-layer structure is shown as an example of a layer structure of the multilayer film 5, but the multilayer film 5 may have a four-layer structure, a five-layer structure, or more. For example, a five-layer structure in which adhesive layers are inserted between the innermost layer 51 and the intermediate layer 52 and between the intermediate layer 52 and the outermost layer 53 may be employed.

In addition, the present invention is not limited to a medical solution bag that contains a medical solution, but includes various infusion bags that contain foods such as nutrients (for example, intravenous nutrition, oral nutrition, tube feeding, etc.) It can be suitably used as a liquid bag.

The embodiments of the present invention are merely specific examples used to clarify the technical contents of the present invention, and the present invention should not be construed as being limited to these specific examples. The scope is limited only by the appended claims.

This application corresponds to Japanese Patent Application No. 2012-111852 filed with the Japan Patent Office on May 15, 2012, the entire disclosure of which is incorporated herein by reference.

Next, although this invention is demonstrated based on an Example and a comparative example, this invention is not limited by the following Example.
(1) Materials used The following resin materials were used in the following Examples and Comparative Examples.
<Random copolymer A>
・ Random A1 (128 ℃)
Metallocene ethylene / propylene random copolymer (melting point: 128 ° C. MFR: 7.0, manufactured by Nippon Polypro)
・ Random A2 (118 ℃)
Metallocene ethylene / propylene random copolymer (melting point 118 ° C. MFR: 3.8 manufactured by Prime Polymer Co., Ltd.)
<Random copolymer B>
・ Random B1 (147 ℃)
Ethylene / propylene random copolymer (melting point: 147 ° C. MFR: 1.8, manufactured by Lee Chang-ei)
・ Random B2 (137 ℃)
Ethylene / propylene random copolymer (Melting point: 137 ° C. MFR: 1.5, manufactured by Basel)
<Thermoplastic elastomer E>
・ Styrene E
(Tensile strength: 23 MPa MFR: 6.0 Glass transition temperature-41 ° C., manufactured by Clayton)
・ Olefinic E
(Tensile strength 45MPa MFR: 1.0 Glass transition temperature -50 ℃ Made by Mitsui Chemicals)
<PP compound-1>
-PT100 (MFR: 1.6 Melting point: 164 ° C, manufactured by Lee Choeisha)
<PP compound-2>
PT100 / ST612 / A-1085S = 20: 50: 30 (mixing ratio)
(ST612 (MFR: 1.8 melting point: 148 ° C, manufactured by Lee Chang-Ei))
(A-1085S (MFR: 1.2 Glass transition temperature: −40 ° C., Mitsui Chemicals)
(2) Production of multilayer film For each example and each comparative example, the resin material shown in (1) was melt-mixed on the basis of the blending ratio (parts by weight) shown in Tables 1 to 5 below to form the innermost layer. 51, the resin material which comprises each of the intermediate | middle layer 52 and the outermost layer 53 was produced. Then, these resin materials were subjected to water-cooled coextrusion and inflation molding to produce a three-layer film having a layer structure shown in Tables 1 to 5 below.
(3) Manufacture of chemical solution bag According to the manufacturing process shown in FIG. 3 and FIG. 4, the chemical solution bag 1 made of the three-layer film obtained in (2) was prepared. The welding conditions of the heat seal 6 of the bag body 3 were as follows: upper mold temperature 155 ° C., lower mold temperature 130 ° C. to 160 ° C. (see Table 1 below), welding pressure 0.5 MPa, welding time 1 second. .
(4) Evaluation test of chemical solution bag (a) Drop plate strength The chemical solution bag 1 with the chemical solution 8 filled in the storage chamber 2 was sterilized at 121 ° C. for 15 minutes. The sterilized chemical solution bag 1 was put into ice water and cooled to around 0 ° C., and then the chemical solution bag 1 was set on a falling plate strength tester. Next, a 6.4 kg iron plate was dropped from a height of 10 cm to the chemical solution bag 1 to confirm whether liquid leakage due to broken bags or pinholes occurred. When there was no bag breakage or liquid leakage, the same test was performed by increasing the drop height of the iron plate by 10 cm until breakage or liquid leakage occurred. The maximum drop height at which bag breakage or liquid leakage does not occur was taken as the measurement result. The results are shown in Tables 1 to 5 below.
(A) Pseudo seal strength From the center part of the chemical | medical solution bag 1 before filling a chemical | medical solution, the strip-like film of width 15mm x length 150mm was cut out upper and lower two pieces together. Next, a peel test was performed on the cut strip samples at a chuck distance of 50 mm and a tensile speed of 200 mm / min, and the maximum peel strength was measured in the measured 100 mm section. And the average value of n number (sample number) of 15 pieces was made into the pseudo seal strength of this test. The results are shown in Tables 1 to 5 below.
(C) Pressure resistance test A 14 cm square with four sides heat sealed at a predetermined temperature, and a sample sterilized at 121 ° C. for 15 minutes in a state filled with a chemical solution in a pressure tester at room temperature of 17 mm Set in the gap. After setting, air was injected into the sample to increase the internal pressure to 200 kPa, and it was confirmed whether the sample burst in 15 minutes. In addition, when it burst within 15 minutes, the elapsed time when it burst was used as the measurement result. The results are shown in Tables 1 to 5 below.
(D) Evaluation Results First, Tables 1 and 2 show examples 1 to 5 including both random copolymer A1 having a melting point of 128 ° C. and random copolymer B1 having a melting point of 147 ° C., and random copolymer A1, A comparison of evaluation results with Comparative Examples 1 and 2 not including any one of B1 is shown. According to Table 2, it was found that the comparative example 1 not including the random copolymer B1 had high peel strength of the pseudo seal, and the comparative example 2 not including the random copolymer A1 was inferior in pressure resistance.

Next, Tables 3 and 4 show examples 6 to 10 including both random copolymer A2 having a melting point of 118 ° C. and random copolymer B2 having a melting point of 137 ° C., and any of random copolymers A2 and B2. A comparison of evaluation results with Comparative Examples 3 to 4 not including one is shown. According to Table 4, similarly to Table 1, it is found that Comparative Example 3 not including random copolymer B2 has high peel strength of the pseudo seal, and Comparative Example 4 not including random copolymer A2 has poor pressure resistance. It was.

Next, Table 5 shows Examples 3, 11, and 12 in which the ratio of the composite polypropylene (PP) resin is in the range of 40 to 80% by weight, and Comparative Examples in which the ratio is out of the range of 40 to 80% by weight. Comparison of evaluation results with 5-6 is shown. According to Table 5, it was found that in Comparative Example 5 in which the ratio of the composite PP resin exceeds 80% by weight, the pressure resistance is inferior, and in Comparative Example 6 in which the ratio is less than 40% by weight, the peel strength of the pseudo seal is high. .

DESCRIPTION OF SYMBOLS 1 Chemical solution bag 2 Storage chamber 3 Bag main body 4 Outlet member 5 Multilayer film 51 Innermost layer 52 Intermediate layer 53 Outermost layer 6 Heat seal 7 Pseudo seal 8 Chemical solution 14 Lower mold 14A Surface 15 Upper mold 15A Surface 16 Concave

Claims

Consists of a laminated structure of at least three layers of an innermost layer, an outermost layer and an intermediate layer between them,
The innermost layer is composed of a mixture of 40 to 80% by weight of a composite polypropylene resin containing at least two types of polypropylene resins having different melting points, and 60 to 20% by weight of a thermoplastic elastomer (E).
The two types of polypropylene resins have a relatively low melting point and a relatively low melting point compared to the random copolymer (A) obtained by polymerization in the presence of a metallocene catalyst and the random copolymer (A). A multilayer film comprising a high random copolymer (B).
The random copolymer (A) is a resin having a melting point of 110 ° C to 135 ° C, and the random copolymer (B) is a resin having a melting point of 140 ° C to 160 ° C. Multilayer film.
The multilayer film according to claim 1 or 2, wherein a ratio of the random copolymer (A) to 100 parts by weight of the composite polypropylene resin is 35 to 85 parts by weight.
The multilayer film according to any one of claims 1 to 3, wherein the thermoplastic elastomer (E) includes an elastomer (C) having a tensile strength of 20 MPa or more and a glass transition temperature of -35 ° C or less.
The multilayer film according to claim 4, wherein the elastomer (C) is a styrene-based elastomer.
A bag body in which a peripheral edge of the multilayer film according to any one of claims 1 to 5 which is overlapped so that the innermost layers face each other is heat-sealed, and a storage chamber for storing a chemical solution is defined therein,
A chemical solution container including a spout for pouring out the chemical solution from the bag body.
Sterilize the chemical container filled with the liquid in the storage chamber at 121 ° C. for 15 minutes, drop a 6.4 kg iron plate into the sterilized chemical container, and the chemical container will not break or leak The chemical | medical solution container of Claim 6 whose falling plate strength represented as maximum fall height is 40 cm or more.
The bag body is formed by adhering inner surfaces of the storage chambers to each other, has a pseudo seal with a peel strength of less than 2N, and the chemical solution container is filled with liquid in the storage chamber Is sterilized at 121 ° C. for 15 minutes, and after increasing the internal pressure of the sterilized chemical solution container to 200 kPa, the chemical solution container according to claim 6 or 7 has a strength capable of withstanding constant pressurization for 15 minutes.
The chemical solution container according to any one of claims 6 to 8, further comprising a chemical solution filled in the storage chamber.
A step of superposing the pair of multilayer films according to any one of claims 1 to 5 so that the innermost layers face each other;
The pair of multilayer films is sandwiched between a lower mold having a flat surface and an upper mold having a concave portion of a predetermined shape formed on the surface to form a heat seal on the periphery of the pair of multilayer films. Forming a bag main body in which a storage chamber for storing a chemical liquid is partitioned, and simultaneously punching the bag main body from the other part of the pair of multilayer films. .