JP6547468B2 - Medical film and high frequency welder processed package - Google Patents

Description

  The present invention relates mainly to a film for high-frequency welding and a package suitable for an infusion bag and the like.

2. Description of the Related Art Conventionally, a medical infusion bag has been manufactured by subjecting a film / sheet made of soft vinyl chloride (PVC) to high-frequency weld processing, forming a bag and filling it with a drug solution.
High-frequency welding is a technology for welding, melting, or embossing a sheet of a thermoplastic resin using heat obtained by moving high-molecular energy by applying high-frequency energy to a thermoplastic resin.

In recent years, the demand for dehalogenation has been high, and films / sheets made of ethylene-vinyl acetate copolymer (EVA), which has similar properties to PVC, are increasingly being used. In order to achieve this, the vinyl acetate content must be high, and there is the concern of thermal deterioration in the production of films and sheets.
Therefore, in the market for medical infusion bags as a whole, cases of heat sealing, trimming and bag-making processing of linear low density polyethylene (LLDPE) or polypropylene (PP) based films and sheets are gradually increasing. (For example, patent documents 1 and 2).

  However, for medical fluid infusion bag processing manufacturers, the cost is also large to upgrade the equipment from the existing high frequency welder processing machine to the heat seal bag making machine, so a film for improving the operation rate using the high frequency welder processing machine It is desirable to provide a sheet.

On the other hand, with PVC and EVA single films / sheets (for example, Patent Document 3), practically it is easy to block at the time of film / sheet production and handling is poor at the time of bag making processing, so the surface is roughened by embossing etc. Often use film sheets.
However, in these cases, the surface is intentionally roughened, so the external haze is high and the content visibility is poor. In addition, in order to emboss, it is necessary to prepare two films and sheets which constitute an infusion bag, and cleaning and UV sterilization in the bag making process in order to ensure the sanitation property of bag manufacture, especially inner surface side. There is a problem that processes such as processing increase and their management becomes more complicated, and it is not preferable from the viewpoint of cost.

For example, in Patent Document 4, the second layer adjacent to the seal layer is mixed with a copolymer of an α-olefin and another monomer and 2 to 15% by mass of a polyamide resin to impart high frequency sealability. There is disclosed a technique for imparting a drop strength at low temperature by using a propylene-ethylene random copolymer or a propylene-based elastomer for the seal layer. However, in the case of such a technology, its high frequency sealability is low, and in practice it is necessary to increase the output of high frequency or take time, which causes problems in terms of production safety and production efficiency.
In the bag-like form that accommodates the contents, assuming that it is used for manufacturing, distribution, storage, etc., it is essential that packaging such as an infusion bag be strong enough not to break even when a load is applied or dropped. Therefore, it is required to combine good processing productivity of the high frequency welder with stable and sufficiently strong seal strength.

On the other hand, medical packages such as infusion bags may also be required to have gas barrier properties at the same time. For example, when storing and distributing oxygen-sensitive drugs, glass ampoules have conventionally been used, but in recent years there have been many changes in packaging to plastic containers in terms of complexity in use and distribution costs, etc. It has become.
As a gas barrier function layer of plastic containers, the general order of gas barrier properties is metal foil> metal deposited film> gas barrier resin, but when metal foil or metal deposited film is used as a gas barrier layer, an adhesive is generally used The lamination method by the dry lamination method which uses is adopted (for example, patent documents 5). However, when the configuration including the adhesive is used for the medical package, there is a concern that the adhesive component may be eluted to the contents side, and there is a problem that the cost increases due to the increase of the manufacturing process.

JP 2002-011839 A JP, 2014-180326, A Japanese Patent Application Laid-Open No. 59-084719 Patent 3972178 gazette Japanese Patent Application Laid-Open No. 2002-028999

  The present invention has been made in view of the above circumstances, and does not use a vinyl chloride resin, and has high-frequency welder processing aptitude, transparency, blocking resistance, drop resistance and load resistance, and components for contents. An object of the present invention is to provide a multilayer film and a package which can be used as a medical package without elution and the like.

  In order to solve the above problems, the present invention provides a coextruded multilayer film in which an outer layer, an intermediate layer, a high frequency sensitive layer, and an inner layer are disposed in this order, the outer layer or intermediate layer is made of polyamide resin, and the high frequency sensitive layer has a vinyl acetate content 10% by weight or more and 30% by weight or less of ethylene-vinyl acetate copolymer and having a thickness of 50 μm or more, and the inner layer is made of a polyolefin resin and is adjacent to the high frequency sensitive layer and has a thickness of 3 μm or more and 50 μm or less The present invention provides a multilayer film for medical use, which is characterized in that the film conforms to the test method for pharmaceutical containers made of plastic according to the Japanese Pharmacopoeia, and a medical package produced by high-frequency welding using the same.

  According to the present invention, the film is mainly composed of a polyolefin resin, can be stably manufactured by good high frequency welder processing aptitude, can be handled without causing problems such as blocking, and further, there is no component elution to contents Since the bag-breaking strength is also high, it is possible to provide a multilayer film and a package that meet the characteristics required as a safe and highly hygienic medical package.

The film of the present invention is a coextruded multilayer film in which an outer layer, an intermediate layer, a high frequency sensitive layer and an inner layer are disposed in this order, and the high frequency sensitive layer and the inner layer are disposed adjacent to each other. When using for the medical package body, package bodies, such as a bag which can accommodate the contents in an inner layer side, can be produced by putting the inner layer side of a film together, and carrying out a high frequency welder processing.
Hereinafter, the configuration of each layer will be described in detail.

<Polyamide resin layer>
The film of the present invention can impart flexibility and strength to the film by providing a polyamide resin layer in the outer layer or the intermediate layer, and when the package falls or a large load is applied to the package. It becomes difficult to break.
In the case where the polyamide resin is disposed in the outermost layer, the film and the package can be given strength, and also the glossiness is improved and the appearance becomes good.
The type of polyamide resin is not particularly limited, but in consideration of impact resistance, low hygroscopicity, low elution, weather resistance, low temperature extrudability during film formation, etc., ring opening polymerization of lactam having 11 or more carbon atoms or Polyamide 11, polyamide 12 or a mixture thereof obtained by condensation polymerization of an ω-amino acid having 11 or more carbon atoms can be suitably used.
Examples of lactams include undecane lactam and lauryl lactam, and nylon 11 and nylon 12 can be obtained from each lactam raw material by a known ring-opening polymerization method.
The lower limit of the thickness of the polyamide resin layer relative to the total thickness of the film is preferably 3% or more, more preferably 5% or more, from the viewpoint of imparting film strength. The upper limit is preferably 15% or less, and more preferably 10% or less, from the viewpoint of maintaining good flexibility of the film.

<Gas barrier layer>
In the film of the present invention, by providing an intermediate layer between the outer layer and the high frequency sensitive layer and forming the intermediate layer with a gas barrier resin, it becomes possible to impart the necessary oxygen barrier property to the medical package. .
As the gas barrier resin, ethylene-vinyl alcohol copolymer (EVOH) or MX nylon (MXD) obtained by polymerizing metaxylene diamine can be suitably used. The use of EVOH is preferred in terms of the balance between gas barrier properties and flexibility.

<High frequency sensitive layer>
The film of the present invention has a high frequency sensitive layer consisting of ethylene-vinyl acetate copolymer (EVA) adjacent to the inner layer. The high frequency sensitive layer refers to a layer which causes dielectric heating by high frequency and imparts high frequency weld processing suitability to the film.

The vinyl acetate content of EVA constituting the high frequency sensitive layer is 10% by mass to 30% by mass, preferably 15% by mass to 25% by mass, and more preferably 20% by mass to 25% by mass.
When the content of vinyl acetate is 10% by mass or more, satisfactory seal strength as a medical package can be obtained by the high frequency welder processing, and when the content of vinyl acetate is 30% by mass or less, multilayer film formation Thermal degradation of EVA does not occur easily, and stable film formation becomes possible.

  The thickness of the high frequency sensitive layer is 50 μm or more, preferably 75 μm or more, and more preferably 100 μm or more. When the lower limit of the thickness is 50 μm or more, satisfactory seal strength as a medical package can be obtained at the time of high frequency welding. The upper limit of the thickness is not particularly limited, but a range which does not have an excessive thickness as a medical package is good, and generally 200 μm or less is suitable.

<Inner layer>
In the film of the present invention, a sealing layer composed of a polyolefin resin is disposed adjacent to the high frequency sensitive layer. The inner layer has a function that the high frequency sensitive layer generates internal heat by high frequency weld processing, and the heat can seal and seal the innermost layers with each other.

The polyolefin resin used for the inner layer is preferably a mixture of component A and component B described below.
Component A of the inner layer is at least one selected from low density polyethylene resin (LDPE) and linear low density polyethylene resin (LLDPE), and preferably has a melting point of 90 ° C. or more and 130 ° C. or less. The use of LLDPE is preferable from the viewpoint of obtaining a film having high seal strength and high transparency.
The lower limit of the melting point of the component A of the inner layer is preferably 95 ° C. or higher, the upper limit is more preferably 125 ° C. or lower, and still more preferably 110 ° C. or lower. When LDPE or LLDPE having a melting point of 90 ° C. or more is used, blocking is less likely to occur, and handling at the time of film formation and at the time of bag-making processing becomes stable. When LDPE or LLDPE having a melting point of 130 ° C. or less is used, melting sealing of the sealing layer using heat generation energy obtained in the high frequency sensitive layer is sufficiently achieved by high frequency welding at the time of bag making, and satisfactory as a medical package Seal strength can be obtained

Component B of the inner layer is preferably at least one selected from high density polyethylene (HDPE) and a norbornene resin having a glass transition temperature of 50 ° C. or more and 140 ° C. or less.
By mixing the component B with the component A, the rigidity and the blocking resistance of the film can be improved.

Here, the norbornene resin refers to a resin having a norbornene skeleton. For example, cyclic olefin polymer (COP), cyclic olefin copolymer (COC), etc. can be used.
The lower limit of the glass transition temperature of the norbornene resin is more preferably 70 ° C. or more, and still more preferably 100 ° C. or more. The upper limit is more preferably 130 ° C. or less, and still more preferably 120 ° C. or less. When the glass transition temperature is 50 ° C. or higher, the winding during film formation and handling during bag making are stable, and when the glass transition temperature is 140 ° C. or less, the extrusion during multilayer film formation is stable. Do.

The mixing ratio of component A to component B in the inner layer is preferably 50% by mass or more and less than 95% by mass, and 5% by mass or more and less than 50% by mass of component B. More preferably, component A is 60% by mass or more and less than 80% by mass, and component B is 20% by mass or more and less than 40% by mass.
If the component A is 50% by mass or more, the sealing layers sufficiently melt and adhere to each other by the heat generation energy obtained in the high-frequency sensitive layer during the high-frequency welding, and if the component A is less than 95% by mass Maintained to facilitate film handling.

  The thickness of the inner layer is 3 μm to 50 μm. 5 micrometers or more are preferable and, as for a lower limit, 10 micrometers or more are more preferable. The upper limit is preferably 45 μm or less, more preferably 25 μm or less. Coextrusion multilayer film film formation is stabilized as it is 3 micrometers or more, and high frequency welder processing can be made favorable as it is 50 micrometers or less.

<Film configuration>
The film of the present invention has a seal layer as the inner layer, a high frequency sensitive layer adjacent to the seal layer, and a polyamide resin layer as the outer layer or the intermediate layer, and the other intermediate layers and outer layers are required gas barriers for the film. It can be configured in consideration of physical properties such as elasticity, flexibility, strength and interlayer adhesion. For example, an adhesive resin layer is disposed between each of the outer layer, the intermediate layer, and the high frequency sensitive layer to improve the interlayer adhesion.
The structural example of the film of this invention is shown below. However, the scope of the present invention is not limited, and various changes can be made without departing from the scope of the invention.
In the layer constitution notation, the polyethylene layer is PE, the polypropylene layer is PP, the gas barrier layer is EVOH or MXD, the polyamide layer is PA, the adhesive resin layer is AD, the high frequency sensitive layer is EVA, and the seal layer is a seal.

・ {PE or PP} / AD / PA / EVOH / AD / EVA / seal ・ {PE or PP} / AD / EVOH / PA / AD / EVA / seal ・ PE or PP} / AD / PA / EVOH / PA / AD / EVA / seal-PA / EVOH / AD / EVA / seal-PA / EVOH / PA / AD / EVA / seal-PA / MXD / AD / EVA / seal-PA / AD / EVOH / AD / EVA / seal・ PA / AD / EVOH / PA / AD / EVA / seal ・ PA / AD / MXD / AD / EVA / seal

  The total thickness of the film of the present invention can be appropriately selected in accordance with the film strength and flexibility as a medical package, the shape and weight of the contents, etc. It is convenient at The film strength is preferably 150 μm or more, and 350 μm or less when flexibility or weight reduction is required.

  It is desirable that the raw material resin itself conforms to the Japanese Pharmacopoeia, in view of the hygienic properties required for multilayer films and packages and compatibility with the Japanese Pharmacopoeia, as the raw material resin constituting the film of the present invention. There is no limitation on

  Although the film of the present invention is not limited by the manufacturing method, it is preferable to form a film by a water-cooling inflation method of co-extrusion from the following related requirements. By selecting the co-extrusion method, lamination can be performed without using an adhesive, the manufacturing cost can be reduced, and the concern of elution to the contents side can be reduced, and by selecting the water-cooled inflation method, transparency is high and It becomes possible to secure the sanitation in the film-made tube.

The medical package of the present invention contains and packages contents using the above-described film of the present invention. The shape of the package can be appropriately selected according to the shape of the content and the purpose of use, and examples thereof include a bag having the periphery of the content sealed by a straight line or a curved line, a pouch having a depth on the bottom and being vertically arranged. Also, a hole can be provided in the seal portion in order to hook the package on the hook.
The manufacturing method of the medical package of the present invention is preferably high frequency welding. The strength and time of the high-frequency output can be selected as appropriate, but within the range in which the seal strength required for the package can be stably processed and produced, it is preferable to perform in a short time with a low output in consideration of safety and production efficiency.

Hereinafter, although an Example demonstrates, this invention is not limited to this.
<Examples 1 to 3, Comparative Examples 1 to 4, Comparative Example 6>
Each layer resin was melt-kneaded and extruded by a single-screw extruder, co-extrusion molded by an inflation method at a resin temperature of 200 ° C., and then quenched by cooling water at 20 ° C. to form a non-oriented multilayer film.
The layer configuration of the film of each example is described in order from the outer layer side.

The raw materials used for each example are as follows.
The melting point and glass transition temperature of the raw material resin were measured in accordance with JIS K 7121.
Further, the term "medical use" refers to one compatible with the Japanese Pharmacopoeia plastic drug container.

PE1: Linear low density polyethylene (melting point 95 ° C, for medical use) + high density polyethylene (melting point 135 ° C, for medical use), mixing mass ratio 50: 50
AD: Maleic anhydride-modified polypropylene-based elastomer, medical use EVOH: Ethylene-vinyl acetate copolymer saponified, ethylene content 32 mol%
PA: Nylon 12
EVA1: ethylene-vinyl acetate copolymer, vinyl acetate content 20% by mass, medical EVA2: ethylene-vinyl acetate copolymer, vinyl acetate content 15% by mass, medical EVA3: ethylene-vinyl acetate copolymer, Vinyl acetate content 25 mass%, general industrial use PE2: Linear low density polyethylene (melting point 121 ° C, for medical use) + high density polyethylene (melting point 135 ° C, for medical use), mixing mass ratio 70:30
PE3: High density polyethylene (melting point 135 ° C) + cycloolefin polymer (glass transition temperature 100 ° C), mixing mass ratio 60: 40

Example 1
PE1 (60 μm) / AD (30 μm) / EVOH (35 μm) / PA (10 μm) / AD (30 μm) / EVA1 (140 μm) / PE2 (15 μm)

Example 2
PA (10 μm) / EVOH (35 μm) / AD (20 μm) / EVA2 (100 μm) / PE2 (5 μm)

Example 3
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / PA (10 μm) / AD (20 μm) / EVA2 (140 μm) / PE3 (15 μm)
Comparative Example 1
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / AD (20 μm) / EVA2 (45 μm) / PE2 (5 μm)

Comparative Example 2
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / AD (20 μm) / EVA2 (70 μm) / PE2 (80 μm)

Comparative Example 3
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / AD (20 μm) / PE2 (50 μm)

Comparative Example 4
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / AD (20 μm) / EVA1 (100 μm)

Comparative Example 5
A film having the same layer configuration as that of Comparative Example 4 was formed into a film by a co-extrusion T-die method, and the surface of EVA1 was embossed.

Comparative Example 6
PE1 (40 μm) / EVA3 (150 μm) / PE2 (40 μm)

The following evaluations were performed on the multilayer film obtained in each example, and the results are shown in Table 2.
<Evaluation Item 1, Transparency>
The haze (%) was measured and evaluated in accordance with JIS K 7105.
○; less than 15% of haze ×; 15% or more of haze

<Evaluation item 2, blocking property>
The film obtained by the inflation method was evaluated from the tube openness according to the following criteria.
○: Can be opened by a simple hand drawing ×: Can not be opened by squeezing by hand The film obtained by the T-die method was evaluated from the unwinding from the film roll according to the following criteria.
○; Unrolling without blocking ×; Unrolling with blocking

<Evaluation item 3, high frequency welder processing aptitude>
After sealing is performed under the conditions of high frequency output scale 45 and high frequency application time of 1 second using NKC-3000S manufactured by Quinlight Electronic Seiko Co., Ltd. in a state where the seal layers of the films are in close contact with each other, The seal strength was measured and evaluated.
○; Seal strength 2.0 kgf / 15mm width or more ×; Seal strength 2.0 kgf / 15 mm width or less

<Evaluation item 4, Japanese pharmacopoeia test>
The film was evaluated according to the test of Table 1 based on the Japanese Pharmacopoeia plastic container test method.
○: When the standard values of all test items are met ×: When one or more test items are nonconforming

<Evaluation item 5, drop bag strength>
With the sealing layers of the films in close contact with each other, using NKC-3000S manufactured by Quinlight Electronics Precision Co., Ltd., high frequency output scale 45, high frequency application time 1 second, seal width 10 mm, 25 cm long, 35 cm wide, 3 sides After sealing and putting in 1 L of water, the other side was sealed under the same conditions to make a bag.
The produced water-filled bags were dropped on a concrete surface from a height of 1 m with four sides horizontal, and evaluated.
;: When the bag is not broken (the seal is missing, the edge is broken, etc.) ;; when the bag is broken

  From the above evaluations, Examples 1 to 3 are all good in transparency, blocking resistance, seal strength by high frequency welder, and drop bag strength, and are also compatible with Japanese Pharmacopoeia plastic drug container test. Also, the film of Example 2 had a good gloss, and the bag of Evaluation Item 5 was particularly beautiful as compared to the others.

On the other hand, Comparative Example 1 had a thin high frequency sensitive layer, Comparative Example 2 had a thick seal layer, Comparative Example 3 had no high frequency sensitive layer, and the seal strength did not reach the standard.
In Comparative Example 4, EVA was exposed in the inner layer and blocking occurred.
Moreover, the comparative examples 1-4 did not measure a falling body strength from said result.
In Comparative Example 5, the EVA surface of the inner layer was embossed to prevent blocking, but the transparency was inferior due to the surface asperity shape.
Comparative Example 6 was not able to conform to the Japanese Pharmacopoeia test due to the use of general industrial EVA.
Moreover, Comparative Examples 5-6 did not have a polyamide resin layer, and the falling bag strength was low.

  According to the film of the present invention, by providing a polyolefin resin seal layer capable of blocking suppression without roughening the surface in the inner layer, a multilayer film having high transparency without the concern of blocking can be obtained and adjacent to the inner layer seal layer By providing the high frequency sensitive layer with an appropriate EVA, it is possible to obtain a multilayer film having good high frequency weld processability. Furthermore, by obtaining a film compatible with the Japanese Pharmacopoeia, it can be suitably used for medical supplies such as medical supplies, packaging materials for medical devices, and infusion bags. As a result, it can also contribute to the effective use of the existing high-frequency welder of packaging material manufacturers.

Claims (6)

In a coextruded multilayer film in which an outer layer, an intermediate layer, a high frequency sensitive layer, and an inner layer are arranged in this order, the outer layer or the intermediate layer is composed of a polyamide resin, and the high frequency sensitive layer is ethylene having a vinyl acetate content of 10% by mass to 30% by mass And at least one selected from a low density polyethylene resin and a linear low density polyethylene resin, which is composed of a vinyl acetate copolymer and has a thickness of 50 μm or more, an inner layer having a melting point of 90 ° C. or more and 130 ° C. or less Component A, at least one selected from a high density polyethylene resin and a norbornene resin having a glass transition temperature of 50 ° C. or more and 140 ° C. or less is the component B, 50% by mass or more and less than 95% by mass of the component A It consists of a polyolefin resin in a proportion of less than wt% to 50 wt% and adjacent to the high-frequency-sensitive layer Is is a 3μm or 50μm or less, the medical multilayer film characterized in that the film to conform to Japanese Pharmacopoeia plastic pharmaceutical container test method. The medical multilayer film according to claim 1, wherein the polyamide resin is nylon 11 or nylon 12. The medical multilayer film according to any one of claims 1 or 2 , which is produced by a water cooling inflation coextrusion method. The medical multilayer film according to any one of claims 1 to 3 , which is used for high frequency welding. A medical package using the medical multilayer film according to any one of claims 1 to 3 . The medical package body produced by the high frequency weld process using the medical multilayer film in any one of Claims 1-3 .