JPH0224148B2 - - Google Patents

Description

〔Technical field〕

The present invention relates to medical packaging containers, and particularly to medical packaging containers that do not undergo deterioration such as discoloration or decrease in adhesive strength due to radiation sterilization. [Prior art and its problems] As a method for sterilizing medical equipment that uses plastic at least in part, such as injection needles, syringes, infusion/blood transfusion sets, shears, artificial organs, etc., there is a method that does not cause heat deformation to the plastic. and low temperature (below 60℃)
Sterilization methods that use disinfectants such as ethylene oxide gas, which can be sterilized with water, are common. However, the ethylene oxide gas sterilization method has a problem in that it requires a long sterilization time of about 6 hours, and a radiation sterilization method that can perform sterilization in a short time has been studied. In the radiation sterilization method, medical devices are placed in a packaging container and then irradiated with radiation. Conventionally, as packaging containers for ethylene oxide gas sterilization, for example, polyethylene terephthalate,
A bag-shaped composite film is used, in which a low melting point resin film layer such as polyethylene or ethylene-vinyl acetate copolymer is laminated as an adhesive layer on the inner surface of a thermoplastic resin film such as polypropylene or polyamide. In order to sterilize the packaging container by replacing or exhausting the air inside the packaging container with ethylene oxide gas, and to avoid bulk during storage or transportation, a part of the airtight packaging container is provided with communication between the internal atmosphere and the external atmosphere, and Packaging containers are used in which a film member made of microorganism-impermeable paper or the like is thermally bonded with an adhesive such as modified butadiene latex or polyethyleneimine lacquer. However, it has been found that when radiation sterilization is performed using such a packaging container, the adhesive turns yellow due to radiation irradiation, and the degree of yellowing increases with the passage of time. Generally, medical devices stored in these packaging containers have an expiration date of three years. For convenience, in order to cause the same degree of change over time as when stored at room temperature for 3 years,
As a forced test, it was found that when the material was stored for one month in air at a temperature of 60°C, it yellowed significantly. Furthermore, a decrease in adhesive strength between the packaging container and the filter member was observed. Therefore, when such packaging containers are sterilized by radiation, there is a problem in that their commercial value is lost, especially as packaging containers for medical instruments and the like. OBJECTS OF THE INVENTION In view of the above-mentioned problems, an object of the present invention is to provide a medical packaging container that does not discolor especially after radiation sterilization and does not reduce the strength of the bonded portion. In accordance with the above object, the present invention provides a medical packaging container in which an airtight bag-like article communicates an internal atmosphere with an external atmosphere, and a microorganism-impermeable filter member is thermally bonded to the airtight bag-like article, at least It is characterized in that an adhesive containing an α-olefin-unsaturated carboxylic acid copolymer is provided on the heat-adhesive surface. Examples of the α-olefin-unsaturated carboxylic acid copolymer include ethylene-unsaturated carboxylic acid copolymer, and the unsaturated carboxylic acid is preferably methacrylic acid, acrylic acid or maleic acid. Furthermore, the unsaturated carboxylic acid is sodium,
It is preferable to use an ionomer resin that is crosslinked with a metal such as zinc, potassium, calcium, or magnesium, and in which 20 to 50% of the carboxylic acid is neutralized. DETAILED DESCRIPTION OF THE INVENTION The present inventors have developed an adhesive that does not discolor due to radiation irradiation, which is used when thermally bonding a microorganism-impermeable filter member that separates the internal atmosphere and external atmosphere to at least a portion of a medical packaging container. As a result of various research to develop the adhesive, we found that by using an α-olefin-unsaturated carboxylic acid copolymer as the adhesive, there is no discoloration and no change in adhesive strength even when irradiated with radiation. Based on this finding, we have completed this invention. The present invention will be described in more detail below with reference to the drawings. As shown in FIGS. 1 to 3, the medical packaging container 1 according to the present invention has a bag-like main body 2 made of, for example, an impermeable synthetic resin sheet, which is opened at a portion, that is, at least one end, and usually at both ends. A cylindrical filter member 5, which communicates the internal atmosphere with the external atmosphere and is impermeable to microorganisms, is attached to a communication portion 6 that communicates the internal atmosphere with the external atmosphere. In the member 5, the α-olefin-unsaturated carboxylic acid copolymer 3 is provided on at least the thermally bonded surface 7 of the filter member 5 to the bag body 2, and the peripheral edge 4 is thermally bonded, so that the bag is sealed. be done. The adhesive made of the α-olefin-unsaturated carboxylic acid copolymer does not change color to yellow or the like when irradiated with radiation, unlike conventional adhesives. 4 and 5 show a modification of the present invention, in which a communication portion 6 between the internal atmosphere and the external atmosphere of the bag-like body 2 made of an impermeable synthetic resin sheet is shown.
A band-shaped filter member 15 that communicates the internal atmosphere with the external atmosphere and is impermeable to microorganisms is thermally bonded to the bag-like body 2 and the filter member 15. through the α-olefin-unsaturated carboxylic acid copolymer 13 provided on the thermally adhesive surface of the filter member
The sheets are thermally bonded to each other, leaving the center portion in the longitudinal direction, and the sheets are thermally bonded to each other at both ends 19 of the bag body 2, thereby sealing the bag. Alternatively, the bag-like body 2 may be formed by folding a single sheet and thermally bonding the sheets together at both ends 19. In this case, it is preferable that the heat-adhesive surface of the sheet is made of a heat-adhesive low-melting resin film. FIGS. 6 and 7 show another modification of the present invention, in which a folded sheet made of an impermeable synthetic resin sheet with a V-shaped cross section is attached to both side edges of two microorganism-impermeable filter members 25 facing each other. By inserting the body 8, the filter member communicates the internal atmosphere and the external atmosphere of the packaging container. α- established in 27
They are thermally bonded via an olefin-unsaturated carboxylic acid copolymer 3. Further, both ends 29 of the filter member are similarly thermally bonded and sealed via the α-olefin-unsaturated carboxylic acid copolymer 23. The impermeable synthetic resin sheet used in the present invention is preferably a radiation-resistant flexible film-forming material, such as polyester such as polyethylene terephthalate or polybutylene terephthalate, polypropylene such as biaxially oriented polypropylene, polyamide, etc. There are composite films, etc., in which a low melting point resin film layer such as polyethylene, ethylene-vinyl acetate copolymer, etc. is laminated on the inner surface of a transparent thermoplastic resin film, and the thickness is 5 to 150 μm, preferably 10 to 60 μm.
The film is preferably at least partially transparent so that the stored items can be seen through. The α-olefin-unsaturated carboxylic acid copolymer used in the present invention has thermal adhesive properties, and
- A copolymer of an olefin (preferably ethylene) and an unsaturated carboxylic acid (eg acrylic acid, methacrylic acid, maleic acid, etc., preferably acrylic acid). Further, it is particularly preferable that the unsaturated carboxylic acid is an ionomer resin having a structure neutralized with a metal in order to prevent discoloration after radiation irradiation. In this case, the long chain molecules have a structure in which they are crosslinked with metal ions. Metals used for crosslinking include sodium, zinc, potassium, calcium, and magnesium. The content of unsaturated carboxylic acid in the α-olefin-unsaturated carboxylic acid copolymer is 0.5 to 20 mol%,
Preferably it is 1 to 4 mol%. Further, the neutralization rate by the metal is 90% or less, preferably 20 to 50%. The reason why the amount of unsaturated carboxylic acid is preferably in the above range is that when it is 0.5 mol % or more, discoloration after radiation irradiation is extremely small, while when it is 20 mol % or less, the resin has excellent physical properties such as flow characteristics. Also, the neutralization rate with metals is 20 to 50%.
When , there is very little discoloration after radiation irradiation, while when it exceeds 90%, physical properties such as flow characteristics of the resin deteriorate. Such an α-olefin-unsaturated carboxylic acid copolymer is an emulsion using water as a solvent before being applied to the filter member, and after being applied to the filter member at 1 to 10 g/m ² , it is dried by, for example, hot air drying. It is applied onto the filter member. Additionally, additives may be added as appropriate. Furthermore, the copolymer is not limited to the above method, and the filter member may be impregnated in advance. The copolymer can be applied or impregnated without impairing the air permeability of the filter member. A bag body is formed by folding the sheet made of the synthetic resin film, a medical device is placed between the sheets, and a microorganism-impermeable cylindrical filter is placed at the periphery of the overlapping portion of the bag body. The member is thermally bonded so that both ends thereof reach both ends of the bag-like body and both ends of the filter member are not closed;
Furthermore, a packaging container is formed by thermally bonding the sheets to each other around the other peripheral edge of the bag-like body, and then sterilization treatment is performed by irradiating with radiation, for example, 1 to 5 Mrad, as shown in FIGS. 1 to 3. A medical packaging container is obtained. Thermal bonding between the bag body and the filter member is usually done by heat sealing, high frequency induction heating, etc.
This is done by melting the α-olefin-unsaturated carboxylic acid copolymer provided as an adhesive while heated to 100°C or higher. As the filter member used in the present invention, in addition to filter paper, it is possible to use synthetic fibers such as polyester, polyethylene, polyamide, etc. or nonwoven fabrics of activated carbon fibers in the form of cylinders, strips, or other shapes. A layer of an adsorbent such as activated carbon fibers, activated clay, activated alumina, zeolite, etc. is provided on any side of the member, preferably on the inner space side of the bag, or these adsorbents are mixed with the filter paper, nonwoven fabric, etc. By doing so, decomposition products generated from the packaging container or the medical device due to radiation irradiation may be adsorbed, thereby preventing the user from feeling a bad odor when the container is opened. The radiation used is
There are electromagnetic radiations such as gamma rays and electron beams, preferably gamma rays, and the irradiation intensity is 1 to 1.
5 Mrad, preferably 2-3 Mrad. In the present specification, the term "impermeable to microorganisms" means a property that is substantially impermeable to bacteria and can maintain a sterile state after sterilization for an extremely long period of time. The pore diameter of the filter member is 0.75 μm or less, preferably 0.45 μm.
It is better to make it less than m. Medical instruments that are housed in the packaging container of the present invention and subjected to radiation sterilization include, for example, injection needles, syringe barrels, catheters, infusion/blood transfusion sets, filters, and the like. Note that the present invention is not limited to the shapes shown in FIGS. 1 to 7 above. For example, the entire packaging container may be composed of a filter member, and the filter members may be coated with α-olefin-unsaturated carboxylic acid at predetermined portions. It may be thermally bonded and sealed via a copolymer. Specific Effects of the Invention As described above, according to the present invention, a medical packaging container is formed by thermally adhering a microorganism-impermeable filter member that communicates the internal atmosphere and the external atmosphere to a sealed bag-like product. Since the filter member is characterized in that an adhesive containing an α-olefin-unsaturated carboxylic acid copolymer is provided on at least the heat-adhesive surface of the filter member, when sterilization is performed by radiation sterilization irradiation, However, discoloration such as yellowing does not occur. As a result, radiation sterilization can be performed without loss of commercial value, especially as a packaging container for radiation sterilization of medical instruments and the like. Furthermore, since the filter member is impermeable to microorganisms and communicates the internal atmosphere of the packaging container with the external atmosphere, decomposition products generated from the packaging container or medical devices due to radiation sterilization will be diffused during storage after sterilization. It escapes to the outside air through the filter member. Therefore, when the packaging container is opened, no foul odor will be emitted due to the decomposition products. Furthermore, since contamination by microorganisms can be avoided during storage after sterilization and the air inside the packaging container can be exhausted, there is an advantage that the packaging container is not bulky during storage or transportation. Further, since the α-olefin-unsaturated carboxylic acid copolymer is provided on at least the thermally bonded surface of the filter member, the adhesive strength of the filter member does not decrease even after radiation irradiation. Further, it is more preferable that the α-olefin is ethylene because it is difficult to be decomposed by radiation. Further, it is preferable that the unsaturated carboxylic acid is acrylic acid, methacrylic acid, or maleic acid because adhesive strength is strong. Also, unsaturated carboxylic acids account for 20-50% of metals.
It is more preferable to use an ionomer resin in which the resin is neutralized in order to prevent discoloration after irradiation with radiation. Next, the present invention will be explained in more detail with reference to Examples. Example 1 A resin made of an ethylene-acrylic acid copolymer with an acrylic acid content of 3 mol% as an adhesive and an emulsion using water as a solvent were applied to a paper filter member at 3 g/m ² and then dried with hot air. Thereafter, the filter member is made into a cylindrical shape, and then a polypropylene syringe barrel is inserted between a bag-like object made by folding a polyethylene terephthalate film with a thickness of 16 μm, and then the filter member is inserted into the folded end of the bag-like object. Hold it so that both ends reach both ends of the bag-like object,
Then, the periphery was hot-bonded. Thereafter, gamma rays of 2.5 Mrad were irradiated, and the degree of coloration of the bond between the bag and the filter member by gamma ray irradiation was measured before and after irradiation. That is, the chromaticity point under the C light source was measured as x, y chromaticity coordinates for each of the unirradiated samples, the samples immediately after irradiation, and the samples stored at 60° C. for one month after irradiation. (x,y)=(0.310,
0.315) as the standard, and the larger the difference is than this value,
Indicates significant discoloration. Incidentally, 20 specimens were prepared, and the average value of the measured values was obtained. The result is the first
Shown in the table. Example 2 Packaging was carried out in the same manner as in Example 1, except that an ionomer resin made by neutralizing 50% of ethylene-acrylic acid copolymer with sodium with an acrylic acid content of 3 mol% was used as the adhesive. When a container was manufactured and a similar test was conducted, the results shown in Table 1 were obtained. Comparative Example 1 Packaging containers were manufactured in the same manner as in Example 1 except that modified butadiene latex (manufactured by Toyo Soda Co., Ltd.) was used as the adhesive, and the same tests were conducted. The results were obtained. Comparative Example 2 In the method of Example 1, a polyethyleneimine lacquer (manufactured by Toyo Morton Co., Ltd.) was used as the adhesive.
When a packaging container was manufactured in the same manner except that the same test was carried out, the results shown in Table 1 were obtained.

[Table] In the above examples, no discoloration was observed before and after irradiation, but in Comparative Examples 1 and 2, yellowing occurred after irradiation, especially those stored at 60°C for one month after irradiation. . Incidentally, when tests were conducted using α-olefin-unsaturated carboxylic acid copolymers other than those shown in the above examples, similar results were obtained. Next, in order to examine the adhesive strength between the bag body and the filter member of the packaging containers obtained in Examples 1 and 2 and Comparative Examples 1 and 2, a tensile test was performed on the bag body and the filter member. Ta. In addition, when pulling, both were pulled in opposite directions at a speed of 200 mm/min, and the force required for pulling when peeling occurred was measured. Table 2 shows the average value of the results of measuring 10 pieces for each item.

[Table] As is clear from the above test, in both Comparative Examples 1 and 2, a decrease in adhesive strength was observed after irradiation with gamma rays. A decrease in adhesive strength may lead to separation of the bag-like body and the filter member that constitute the medical packaging container, which is not preferable for maintaining the sterile state after sterilization. However, in Examples 1 and 2, no adhesive was used. No decrease in strength was observed. Similar results were also obtained in tests conducted using other α-olefin-unsaturated carboxylic acid copolymers.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a medical packaging container according to the present invention, FIG. 2 is a sectional view taken along line - in FIG. 1, and FIG. 3 is a sectional view taken along line - in FIG.
FIG. 4 is a perspective view showing a modification of the present invention, FIG. 5 is a sectional view taken along the line - in FIG. 4, and FIG. 6 is a perspective view showing another modification of the invention. ,
Further, FIG. 7 is a sectional view taken along the line --- in FIG. 6. 1, 11, 21...Packaging container, 3, 13, 23
...α-olefin-unsaturated carboxylic acid copolymer, 5,15,25...Filter member, 7,1
7, 27...thermal adhesive surface.

Claims (1)

[Scope of Claims] 1. A medical packaging container in which a filter member that communicates the internal atmosphere with the external atmosphere and is impermeable to microorganisms is thermally bonded to a sealed bag-like article, at least on the thermally bonded surface of the filter member. A medical packaging container characterized by being provided with an adhesive containing an α-olefin-unsaturated carboxylic acid copolymer. 2 α-olefin-unsaturated carboxylic acid copolymer is ethylene-unsaturated carboxylic acid copolymer,
The medical packaging container according to claim 1, wherein the unsaturated carboxylic acid is at least one of methacrylic acid, acrylic acid, and maleic acid. 3 α-olefin-unsaturated carboxylic acid copolymer is ethylene-unsaturated carboxylic acid copolymer,
The medical packaging container according to claim 1, wherein the unsaturated carboxylic acid is an ionomer resin neutralized by 20 to 50% with metal.