JP2016179569A - Medical film and high-frequency welded package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer film which does not use a vinyl chloride resin, has high-frequency welding suitability, transparency and blocking resistance, causes no elution to an ingredient, and can be used for a medical package; and a package.MEANS FOR SOLVING THE PROBLEM: There are provided a medical multilayer film having a seal layer in an innermost layer and a high-frequency sensitive layer adjacent to the seal layer, where the seal layer is formed of a polyolefin resin and has a thickness of 3 μm or more and 50 μm or less, the high-frequency sensitive layer is formed of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 mass% or more and 30 mass% or less and has a thickness of 50 μm or more, and the film complies with plastic-made medicine container test method by the Japanese Pharmacopoeia; and a medical package produced by high-frequency welding using the same.SELECTED DRAWING: None

Description

  The present invention relates to a film for high-frequency welder processing that is suitable mainly for an infusion bag and the like, and a package.

Conventionally, a medical infusion bag has been manufactured by processing a film / sheet made of soft vinyl chloride (PVC) by high-frequency welding and filling it with a bag / chemical solution.
The high-frequency welder processing is a technique that uses heat obtained by applying high-frequency energy to a thermoplastic resin to move a polymer chain, and welds or cuts or stamps the thermoplastic resin sheet.

In recent years, there has been a trend of dehalogenation, and there are an increasing number of cases where films and sheets made of ethylene-vinyl acetate copolymer (EVA) with similar physical properties are used. To make EVA suitable for high-frequency welder processing, In addition, since the vinyl acetate co-content must be high, there is a concern about thermal deterioration in the production of films and sheets.
Therefore, as a whole market for medical infusion bags, cases of heat-sealing, trimming, and bag-making processing using linear low density polyethylene (LLDPE) or polypropylene (PP) -based films and sheets are gradually increasing. (For example, Patent Documents 1 and 2).

  However, for manufacturers of medical infusion bags, it is expensive to upgrade equipment from an existing high-frequency welder to a heat-sealing bag making machine. The provision of a sheet is desired.

On the other hand, in the case of a single film or sheet of PVC or EVA (for example, Patent Document 3), the surface is practically roughened by embossing or the like because it is easily blocked at the time of film / sheet production and handling at the time of bag making is poor. There are many cases that use a film sheet.
However, in these cases, since the surface is intentionally roughened, the external haze is high and the content visibility is poor. In addition, in order to emboss, it is necessary to prepare two front and back films and sheets that make up the infusion bag. In order to ensure the hygiene of the bag product, especially the inner surface, washing and UV sterilization are performed. There is a problem that the number of processes such as processing is increased and the management thereof is more complicated, and in addition, it is not preferable from the viewpoint of cost.

On the other hand, gas barrier properties are sometimes required for medical packaging bodies including infusion bags. In the past, glass ampoules have been used to store and distribute oxygen-sensitive drugs. However, in recent years, the packaging has been changed to plastic containers in view of the complexity and distribution costs during use. Yes.
As a gas barrier functional layer of a plastic container, the general order of gas barrier property is metal foil> metal vapor deposition film> gas barrier resin, but when metal foil or metal vapor deposition film is used as a gas barrier layer, generally an adhesive or the like A laminating method using a dry laminating method is used (for example, Patent Document 4). However, when a configuration including an adhesive is used for a medical packaging body, there is a concern that the adhesive component may be eluted to the contents side, and there is a problem that the cost is increased due to an increase in manufacturing steps.

JP2002-011839 JP 2014-180326 A JP 59-084719 JP2002-028999

  The present invention has been made in view of the above circumstances, does not use a vinyl chloride resin, has high-frequency welder suitability, transparency, anti-blocking properties, and has no elution to the contents. It aims at providing the multilayer film which can be used for, and a package.

  In order to achieve the above object, the present invention provides a multilayer film having an innermost seal layer and a high-frequency sensitive layer adjacent to the seal layer, wherein the seal layer is made of a polyolefin resin and has a thickness of 3 μm or more and 50 μm or less. The high-frequency sensitive layer is made of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10% by mass to 30% by mass and has a thickness of 50 μm or more, and the film conforms to the Japanese Pharmacopoeia plastic drug container test method. Provided are a medical multilayer film and a medical packaging body produced by high frequency welding using the same.

  According to the present invention, a film mainly composed of a polyolefin-based resin, which can be stably manufactured with good suitability for high-frequency welder processing, can be handled without causing problems such as blocking, and further has no elution to the contents. It is possible to provide a multilayer film that satisfies the required characteristics as a safe and highly hygienic medical package, and a package.

<Sealing layer>
In the film of the present invention, a seal layer composed of a polyolefin resin having a thickness of 3 μm or more and 50 μm or less is disposed on the innermost layer.
The polyolefin resin used for the seal layer is preferably used by mixing component A and component B.

  Component A of the sealing layer is at least one selected from a low density polyethylene resin (LDPE) and a linear low density polyethylene resin (LLDPE), and preferably has a melting point of 90 ° C. or higher and 130 ° C. or lower. From the viewpoint of obtaining a film having high sealing strength and high transparency, use of LLDPE is suitable.

  The melting point of component A of the seal layer is preferably in the range of 90 ° C. or higher and 125 ° C. or lower, more preferably 95 ° C. or higher and 110 ° C. or lower. When LDPE or LLDPE having a melting point of less than 90 ° C. is used, there is a greater concern about blocking, and winding during film formation and handling during bag making become difficult. When LDPE or LLDPE having a melting point higher than 130 ° C. is used, the melt sealing of the sealing layer using the heat generated by the high-frequency sensitive layer is likely to be incomplete at the time of bag making by high-frequency welder processing. As a result, it becomes difficult to obtain satisfactory seal strength.

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

Here, the norbornene-based resin refers to a resin having a norbornene skeleton. For example, a cyclic olefin polymer (COP) or a cyclic olefin copolymer (COC) can be used.
The glass transition temperature of the norbornene resin is preferably 70 ° C. or higher and 130 ° C. or lower, more preferably 100 ° C. or higher and 120 ° C. or lower. When the glass transition temperature is less than 50 ° C., there is a greater concern about blocking, and winding during film formation and handling during bag making becomes difficult. When the glass transition temperature is higher than 140 ° C., extrusion during the formation of the multilayer film becomes difficult.

The mixing ratio of component A and component B in the seal layer is preferably such that component A is 50% by mass or more and less than 95% by mass, and component B is 5% by mass or more and less than 50% by mass. 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.
When component A is less than 50% by mass, it becomes difficult to melt and seal the sealing layer with the heat generated by the high-frequency sensitive layer during high-frequency welder processing. It becomes.

  The thickness of the sealing layer is 3 μm or more and 50 μm or less, preferably 5 μm or more and 45 μm or less, more preferably 10 μm or more and 25 μm or less. When the innermost seal layer thickness is less than 3 μm, stable extrusion is difficult at the time of forming the multilayer film, and when it is thicker than 50 μm, the suitability for high frequency welder processing in the bag making process is inferior.

<High-frequency sensitive layer>
In the film of the present invention, a high-frequency sensitive layer made of an ethylene-vinyl acetate copolymer (EVA) is disposed adjacent to the seal layer. Here, the high-frequency sensitive layer refers to a layer imparting suitability for high-frequency welder processing.

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 vinyl acetate content is less than 10% by mass, it is difficult to obtain a satisfactory sealing strength as a medical packaging body during high-frequency welding. When the vinyl acetate content is higher than 30%, a multilayer film is formed. There is a growing concern about EVA thermal degradation, and stable film formation becomes difficult.

The thickness of the high-frequency sensitive layer is 50 μm or more, and the thickness range is preferably 75 μm or more, more preferably 100 μm or more. When the high-frequency sensitive layer thickness is less than 50 μm, it is difficult to obtain a satisfactory seal strength as a medical packaging body during high-frequency welder processing.
The upper limit of the thickness of the high-frequency sensitive layer is not particularly limited, but it can be said that a thickness of 200 μm or less is sufficient as long as it does not have an excessive thickness as a medical package.

<Gas barrier layer>
The film of the present invention can be provided with an oxygen barrier property often required for a medical package by providing a gas barrier layer in the intermediate layer. Here, the intermediate layer refers to a layer located between the high-frequency sensitive layer and an outer layer described later.
As the resin constituting the gas barrier layer, ethylene vinyl alcohol copolymer (EVOH) and polyamide resin (PA) are generally known and can be preferably used. Among polyamide resins, MX nylon (MXD) in which metaxylenediamine is polymerized is more preferable. From the viewpoint of gas barrier properties and flexibility, it is more preferable to use EVOH.

<Whole film>
The film of the present invention has a seal layer as an innermost layer and a high-frequency sensitive layer adjacent to the seal layer, and other intermediate layers and outer layers have gas barrier properties, flexibility, strength, interlayer required for the film. It can be configured in consideration of physical properties such as 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 modifications can be made without departing from the spirit of the invention.
In the layer structure notation, the polypropylene layer is denoted as PP, the polyethylene layer as PE, the adhesive resin layer as AD, the high frequency sensitive layer as EVA, and the seal layer as seal.

・ PE / EVA / Seal ・ PP / EVA / Seal ・ PE / AD / EVOH / AD / EVA / Seal ・ PP / AD / EVOH / AD / EVA / Seal ・ PE / AD / MXD / AD / EVA / Seal ・ PA / EVOH / AD / EVA / Seal ・ PA / MXD / AD / EVA / Seal

  Although the manufacturing method of the film of the present invention is not limited, it is preferable that the film is formed by a co-extrusion water-cooled inflation method from the following requirements. By selecting the co-extrusion method, it is possible to laminate without using an adhesive, reducing the manufacturing cost, and reducing the possibility of elution to the contents side, and by selecting the water-cooled inflation method, the transparency is high and It becomes possible to ensure the hygiene in the tube formed into a film.

  The raw material resin constituting the film of the present invention is desirably in conformity with the Japanese Pharmacopoeia in view of hygiene and compatibility with the Japanese Pharmacopoeia required for multilayer films and packaging bodies. It is not intended to limit.

Hereinafter, although an example explains, the present invention is not limited to this.
<Examples 1-3, Comparative Examples 1-4, Comparative Example 6>
Each layer resin was melt kneaded and extruded with a single screw extruder, coextruded at a resin temperature of 200 ° C. by an inflation method, and then rapidly cooled with 20 ° C. cooling water to obtain an unstretched multilayer film.
The layer structure of the film in each example will be described in order from the outer layer side.

The raw materials used in each example are as follows.
The melting point and glass transition temperature of the raw material resin were measured according to JIS K7121.
Medical use refers to those that are compatible with Japanese pharmacopoeia plastic drug containers.

PE1: LLDPE, melting point 95 ° C., medical (50% by mass) + HDPE, melting point 135 ° C., medical (50% by mass)
AD: Maleic anhydride-modified polypropylene elastomer, medical EVOH: saponified ethylene-vinyl acetate copolymer, ethylene content 32 mol%
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% by mass, general industrial PE2: LLDPE, melting point 121 ° C., medical (70% by mass) + HDPE, melting point 135 ° C., medical (30% by mass)
PE3: HDPE, melting point 135 ° C. (60% by mass) + cycloolefin polymer, glass transition temperature 100 ° C. (40% by mass)

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

<Example 2>
PE1 (30 μm) / AD (20 μm) / EVOH (35 μm) / AD (20 μm) / EVA2 (80 μm) / PE2 (5 μm)

<Example 3>
PE1 (30 μm) / AD (20 μm) / EVOH (35 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 structure as that of Comparative Example 4 was formed by a coextrusion T-die method, and surface embossing was performed on the EVA1 surface.

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

The multilayer film obtained in each example was evaluated as follows, and the results are shown in Table 1.
<Evaluation item 1, transparency>
Haze (%) was measured and evaluated according to JIS K 7105.
○; Haze less than 15% ×; Haze 15% or more

<Evaluation item 2, blocking property>
The film obtained by the inflation method was evaluated according to the following criteria from the tube opening property.
○: When opening with simple hand ironing ×: When opening with hand ironing The film obtained by the T-die method was evaluated according to the following criteria from unwinding from a film roll.
○: When unwinding without blocking ×; When unwinding with blocking

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

<Evaluation item 4, Japanese Pharmacopoeia>
The film was subjected to the tests shown in Table 1 based on the Japanese Pharmacopoeia plastic container test method and evaluated.
○: When it conforms to the standard value of all the test items ×;

From the above evaluations, Examples 1 to 3 are all excellent in transparency, blocking resistance, and seal strength by a high-frequency welder, and are suitable for the Japanese Pharmacopoeia plastic drug container test.
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.
In Comparative Example 5, embossing was performed on the EVA surface of the inner layer and blocking could be prevented, but the transparency was inferior due to the uneven surface shape.
Comparative Example 6 could not be adapted to the Japanese Pharmacopoeia test due to the effect of using general industrial EVA.

  According to the film of the present invention, by providing a polyolefin-based resin seal layer capable of suppressing blocking without roughening the surface on the innermost layer, a multilayer film having high transparency without fear of blocking can be obtained, and the innermost layer seal layer can be obtained. By providing an appropriate EVA in the adjacent high-frequency sensitive layer, a multilayer film with good suitability for high-frequency welder processing can be obtained. Furthermore, by obtaining a film suitable for the Japanese Pharmacopoeia, it can be suitably used for medical packaging such as pharmaceuticals, medical device packaging materials and infusion bags. In other words, it can also contribute to the effective use of the existing high-frequency welder processing machine of the packaging material manufacturer.

Claims (4)

  In a multilayer film having an innermost seal layer and a high-frequency sensitive layer adjacent to the seal layer, the seal layer is made of a polyolefin resin and has a thickness of 3 μm to 50 μm, and the high-frequency sensitive layer has a vinyl acetate content of 10 mass. And a multilayer film for medical use, characterized in that it is composed of an ethylene-vinyl acetate copolymer of not less than 30% and not more than 30% by weight and has a thickness of 50 μm or more, and the film conforms to the Japanese Pharmacopoeia plastic drug container test method, and Medical packaging made by high frequency welder processing.   The sealing layer has a melting point of 90 ° C. or higher and 130 ° C. or lower of a low density polyethylene resin or a linear low density polyethylene resin as component A, a high density polyethylene resin, a glass transition temperature of 50 ° C. or higher and 140 ° C. or lower. 2. The medical use according to claim 1, wherein any one or more of norbornene-based resins are used as Component B, Component A is contained in a proportion of 50 to 95% by mass, and Component B is contained in a proportion of 5 to 50% by mass. A multilayer film, and a medical packaging produced using the multilayer film by high-frequency welding.   The medical multilayer film according to claim 1 or 2, wherein the intermediate layer has a gas barrier layer, and a medical packaging body produced by high-frequency welding using the same.   The medical multilayer film according to any one of claims 1 to 3, which is produced by a water-cooled inflation coextrusion method, and a medical packaging body produced by high frequency welding using the same.