JP3676909B2 - Medical cap - Google Patents

Description

【００４０】
表１より明らかなように、１層の熱可塑性エラストマー栓からなる比較例１と較べて、積層した各実施例はプラスチック針・金属針のどちらに対しても抜け落ちることはなく良好であり、積層した効果がはっきりと認められる。特に、栓体の形状を多角柱とした実施例２及び４は特に効果が顕著に現れた。また、１層のゴム栓である比較例２と較べ、針刺し、針抜き抵抗値は小さいため取扱いが容易となる。したがって、本発明の医療用キャップは、製造工程を簡便化することができると共に、針抜けに対する保持力に優れ、針の抜け落ち、薬品の漏れが解消される。
【００４１】
【発明の効果】
本発明は、熱可塑性エラストマー、ゲル状樹脂、低密度ポリエチレン、これらとゴムを練り混んだ混合物のいずれかからなる薄層のみを積層してなる栓体を有する医療用キャップであるので、針抜けに対する保持力、復元力が向上し、針抜けに対する保持力及び針抜け後の再シール性に優れた医療用キャップを提供することができる。
【図面の簡単な説明】
【図１】 ゴムの一般的な成形工程を示すフローチャートである。
【図２】 樹脂の一般的な成形工程を示すフローチャートである。
【図３】 刺さった針に荷重がかかった状態にある本発明の医療用キャップの断面図である。
【図４】 針を抜き取りとりつつある状態の本発明のキャップの断面図である。
【図５】 本発明の医療用キャップに用いる栓体の積層の形態の一実施例を示す栓体の断面図である。
【図６】 本発明の医療用キャップに用いる栓体の積層の形態の他の一実施例を示す栓体の断面図である。
【図７】 本発明の医療用キャップの一部断面斜視図である。
【図８】 自己密閉性試験の実験概略図である。
【図９】 保持力試験の実験概略図である。
【符号の説明】
１ キャップ
２ 栓体
３ ケーシング[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cap for a medical infusion container. More specifically, the present invention relates to a medical cap that has excellent holding force against needle removal and improved resealability after needle removal.
[0002]
[Prior art]
Conventionally, rubber caps have been widely used as plugs for medical caps. However, these rubber plugs undergo a complex process as shown in FIG. In addition, there are many kinds of additives, and scrap is generated in each process, so that the productivity is poor. That is, while the casing is manufactured by injection molding, the rubber plug body needs to be vulcanized after press molding, and it is necessary not only to assemble these after separately manufacturing, but also to raise the unit price. Had.
[0003]
In order to solve this problem, it was considered to use a thermoplastic elastomer, which is a resin having elasticity, as a cap body. In this technology, since the casing and the plug are both made of resin, they can be manufactured by simple injection molding as shown in FIG. 2 and do not require a vulcanization step as in the case of rubber plugs. The process problem is solved in that it can be obtained. Also, with this technology, an elastic body having a wide range of physical properties from soft vulcanized rubber to plastic can be obtained by changing the chemical structure of the material. Furthermore, the scrap produced in the molding process can be reused and the productivity is high.
[0004]
[Problems to be solved by the invention]
However, thermoplastic elastomers have the property that residual strain is large, rubber elasticity is inferior, stress relaxation, and creep phenomenon easily occur. For this reason, the holding power with respect to needle removal which is an important element as a cap of an infusion container is low, and the infusion needle easily falls out of the cap during infusion. Moreover, the resealability after needle removal is poor, and there is a problem that chemicals ooze out from the hole formed in the plug after needle removal.
[0005]
In order to solve this problem, a technique using a plug body in which rubber and a thermoplastic elastomer are overlapped is disclosed, but a complete solution to the problem of holding force against needle removal and resealability after needle removal has not been made. In addition, since the rubber plug is still used, the actual situation is that the problem in the process has not been solved.
[0006]
The subject of this invention is providing the medical cap which was excellent in the retention strength with respect to needle | hook removal, the resealability after needle removal, and eliminated the problem in the process.
[0007]
[Means for Solving the Problems]
The present inventor is able to manufacture a cap excellent in retention force against needle removal and resealability after needle removal by adopting a structure in which a stopper made of a thermoplastic elastomer or the like is formed of a thin layer. I found it.
[0008]
The reason why the present invention has resistance to needle omission is, for example, due to the holding effect of the needles at the contact surfaces between the thin layers of thermoplastic elastomer. FIG. 3 is a cross-sectional view of the medical cap of the present invention in a state where a needle is stuck in the cap of the present invention and a load is applied in a direction in which the needle is about to fall off. In the figure, 1 is a medical cap, 2 is a plug formed by laminating each thin layer of a, b and c, 3 is a casing, 4 is a deformation burr of each thin layer when the needle is pulled out, 5 is Shows the needle. That is, at the contact surface portion of each thin layer, the thin layer is deformed as shown in FIG. Moreover, compared with the plug body which consists of one layer by changing the physical property for each layer and having specificity, it improves comprehensively as a plug body by making use of the effect each layer has.
[0009]
On the other hand, the effect of the present invention in resealability after needle removal is due to the restoring effect of returning to the original shape even if each thin layer is independent in addition to the specificity of each layer. FIG. 4 is a cross-sectional view of the medical cap of the present invention in a state at an arbitrary moment from when the needle is stuck in the cap of the present invention until it is extracted. In the figure, 1 is a medical cap, 2 is a plug formed by laminating each thin layer of a, b and c, 3 is a casing, 4 is a deformation burr of each thin layer when the needle is pulled out, 5 is Shows the needle. In other words, in the present invention, the lower thin layers 2c and 2b support the needle and prevent the liquid from leaking out, whereas the upper thin layer 2a from which the needle has been completely removed has a hole due to the restoring force. Closes to prevent leakage. As a result, the sealing performance after needle removal is improved. Accordingly, the sealing performance increases as the number of thin layers increases from the principle of sealing the plug.
[0010]
It is most suitable to use a thermoplastic elastomer as the material of the cap body of the present invention. Examples of the thermoplastic elastomer include hydrogenated polystyrene elastomers, polyvinyl chloride elastomers, polyolefin elastomers, polyurethane elastomers. And polyester elastomers and polyamide elastomers. Since these can be subjected to the same injection molding process as that of a casing made of resin, it is not necessary to assemble them separately as in the case of a conventional rubber plug, and there is a process advantage.
[0011]
The present inventor has also found that the above effect can be obtained even in a plug formed by laminating a thin layer made of any one of a thermoplastic elastomer, a gel-like resin, low-density polyethylene, and a mixture obtained by kneading these with rubber. These have not only the above effects, but also can be injection-molded in the same manner as thermoplastic elastomers, so that problems in conventional processes can be solved.
[0012]
Examples of the gel resin include ethylene gel materials, urethane gel materials, silicon gel materials, acrylic gel materials, vinyl chloride gel materials, and the like. Examples of types of rubber blended with these materials include butyl rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, and acrylic rubber.
[0013]
It has also been found that these effects can be improved by making the plug body a columnar body having a polygonal shape, a flower shape, or a star shape as the bottom instead of a cylindrical shape as in the past, and attaching a fistula to the plug body. It was. In addition, the plug body also has a fuzzy shape by having a bottom with a substantially circular bottom and having a slit with a slit extending in the center direction from the outer periphery or a rib extending in the circumferential direction from the center. I found out that The reason why these inventions solve the above-mentioned problems is that by making the shape of the plug body a polygonal column instead of a cylinder, fuzziness occurs on the contact surface with the casing, and the stress per unit is segmented. . That is, it is because the restoring force with respect to the stress imposed on the plug body increases by dividing into small pieces instead of the large side face. Further, since the resistance to stress is strong and the holding force is improved, the holding force against needle removal is also excellent.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a medical cap having a plug formed by laminating only a thin layer composed of any one of a thermoplastic elastomer, a gel-like resin, low-density polyethylene, and a mixture obtained by kneading these with rubber. The type of the thermoplastic elastomer is not particularly limited, and various known ones can be suitably used in addition to those already described. In particular, Aron Kasei's thermoplastic elastomer, trade name "AR-860C", Mitsubishi Chemical's thermoplastic elastomer, trade name "Lavalon T-331C", Mitsubishi Chemical's thermoplastic elastomer, trade name "Lavalon SR-04" Is optimally usable.
[0015]
As a material for the thin layer, in addition to the thermoplastic elastomer, any of gel resin, low density polyethylene, rubber and thermoplastic elastomer, gel resin, and low density polyethylene (hereinafter abbreviated as high elastic resin). A mixture in which one or more kinds are kneaded can be used. The blending ratio of the rubber and the highly elastic resin is not particularly limited, but is preferably in the range of 1: 9 to 8: 2 by weight ratio. An increase in the amount of rubber is not preferable in terms of difficulty in injection molding. On the other hand, when the rubber compounding amount is too small, the needle drop resistance value cannot be improved depending on the material of other thin layers.
[0016]
The thickness of the thin layer constituting the plug body does not need to be uniform and can have a certain width, but is preferably 1 mm or more and 30 mm or less. Further, the number of thin layers is not particularly limited, but the effect is remarkable when there are three or more layers. That is, it is preferable to have two or more thin-layer joint surfaces. In addition, although the upper limit of the number of the thin layers to provide is not specifically limited, when the thickness of a stopper and the thickness of a thin layer are considered, it will be about 6 layers.
[0017]
The term “lamination” in the present invention is not particularly limited with respect to the form of superposition of thin layers. In addition to the simple superposition of thin layers as in the example shown in FIG. 3, for example, as shown in FIG. The form which wraps the material used as another material, the form which overlaps like FIG. 6, etc. are contained. That is, if it is a form of superposition where the inserted needle passes through the joining surface of the thin layer, it is interpreted as a lamination referred to in the present invention.
[0018]
It is preferable that the physical properties of adjacent thin layers, particularly the elastic modulus, are different. Since the present invention depends on the effect of deformation of the thin layer at the contact surface of the thin layer, the effect is more prominent when the deformation rate is non-uniform than when the deformation is exactly the same at the contact surface. . In general, when comparing the material hardness of the upper and lower thin layers, increasing the hardness of the lower material can support the depression of the upper part, which is the main component of the plug body. it can.
[0019]
In addition, the contact surface of each thin layer may adhere | attach resin by multilayer molding, and may just overlap. In addition, when laminating with a multi-material molding machine, there is a case where welding is performed between the layers and the line bonding portion in the laminating portion is lost, but even in this case, the effect is recognized.
[0020]
The order in which the thin layers are arranged is not particularly limited, but in the case of three or more layers, a thermoplastic elastomer is used on the outside, and a gel resin, low-density polyethylene, or rubber is kneaded and mixed with the intermediate layer. A thin layer made of any of the mixtures may be used. Thermoplastic elastomers are often inferior in resilience compared to gel-like resins, low-density polyethylene, or a mixture of these and rubber kneaded, so these materials can be used to ensure sealability in the intermediate layer. A thin layer is used.
[0021]
The shape of the plug used in the cap of the present invention is not particularly limited. For example, if the bottom surface is a polygonal, flower-shaped or star-shaped column, the needle drop resistance value and the resealability after needle removal Leads to improvement. This is based on the fact that by making the plug body into an octagonal column shape instead of a cylinder, the casing contact surface of the plug body is fuzzy and stress is segmented, so that the restoring force is improved. FIG. 7 is a partial cross-sectional perspective view of a cap with a regular octagonal plug as an embodiment of the present invention. In FIG. 1, 1 is a cap, 2 is a plug body made of 2a, 2b and 2c, 3 is a casing, 6 is a casing contact surface, 7 is a fistula, and 9 is a needle puncture hole. Although not shown, the cap is usually provided with a pull top lid, and the figure shows a state in which the pull top lid is removed. The needle inserted from the needle puncture hole 9 is supported by the internal stress from the plug body 2 so as not to come off, but in a conventional plug body having no fuzz, the stress is uniformly transmitted over a wide area. , Resilience did not show much. However, in the present invention, by providing the flange 7, the stress received by these is segmented for each flange 7, so that the restoring force of the plug body is improved, and as a result, the holding force against needle removal and the needle stick after needle removal. The resealability of the hole 9 is improved. Of course, the present invention is not limited to these shapes, and the present invention can be achieved as long as the flies are provided in some form.
[0022]
The joining method of the cap of the present invention and the infusion container is not particularly limited, and may be joined by a known method. The cap of the present invention can also be applied to a stopper for piercing or holding a needle or tube, for example, a vial stopper for a drug or reagent.
[0023]
The material of the plug used in the medical cap of the present invention is a thermoplastic elastomer that can be produced in the same process as the casing, so that the casing is injected as is conventionally done in the production process. There is no need to vulcanize only the rubber that has been molded and pressed in a separate process and then assemble the two parts. After molding the casing, the number of thin layers that provide the plug in the casing is injected. Since the cap is completed when it is molded, it can be advantageously manufactured in the process. Of course, the present invention is not limited to the above manufacturing method, and the present invention can also be achieved by a method in which a plug body and a casing are separately manufactured and assembled by insert molding as in the prior art.
[0024]
【Example】
Hereinafter, the present invention will be described in detail based on examples. However, the present invention is not limited to the examples.
[0025]
The medical cap was manufactured using the plug body manufactured on the conditions described next, and this was made into each Example and a comparative example. In the examples, the insert molding is a method in which a thin layer constituting the casing and the plug body is separately molded, and the thin layer is sequentially fitted into the casing at the time of manufacturing the cap. The molding by the multi-material molding machine manufactured by repeating injection molding as a surface is shown. In addition, the material of the plug used in each Example and Comparative Example is as follows.
Elastomer 1 ··· Aron Kasei Co., Ltd., thermoplastic elastomer, trade name "AR-860C"
Elastomer 2 ... Made by Mitsubishi Chemical Corporation, thermoplastic elastomer, trade name "Lavalon T-331C"
Elastomer 3 ··· Mitsubishi Chemical Co., thermoplastic elastomer, trade name "Lavalon SR-04"
Gel-like resin: Cosmo Keiki Co., Ltd., gel-like resin, trade name “Cosmogel”
Low-density polyethylene: Showa Denko, low-density polyethylene, trade name "J-lakes M112"
Kneaded rubber 1 ... 4 parts by weight of elastomer 1 mixed with 1 part by weight of butadiene rubber Kneaded rubber 2 ... 4 parts by weight of gel-like resin per 1 part by weight of butadiene rubber Kneaded rubber mixture 3... Mixture of low-density polyethylene 4 parts by weight with respect to 1 part by weight of butadiene rubber.
(Example 1)
A cylindrical plug body made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of elastomer 2 having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set on the casing by simultaneous molding. A cap was manufactured.
[0027]
(Example 2)
A regular hexagonal prismatic plug body made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of elastomer 2 having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set in the casing by simultaneous molding. A medical cap was manufactured.
[0028]
(Example 3)
A cylindrical plug made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of gel resin having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set on the casing by simultaneous molding. A medical cap was manufactured.
[0029]
(Example 4)
A special hexagonal prismatic plug body consisting of a thin layer a made of elastomer 1 with a thickness of 2 mm, a thin layer b made of gel resin with a thickness of 3 mm, and a thin layer c made of elastomer 3 with a thickness of 2 mm. To produce a medical cap.
[0030]
(Example 5)
A cylindrical plug body made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of low density polyethylene having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set on the casing by simultaneous molding. A medical cap was manufactured.
[0031]
(Example 6)
A cylindrical plug made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of kneaded rubber 1 having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set on the casing by simultaneous molding. A medical cap was manufactured.
[0032]
(Example 7)
A cylindrical plug made of a thin layer a made of elastomer 1 having a thickness of 2 mm, a thin layer b made of kneaded rubber 2 having a thickness of 3 mm, and a thin layer c made of elastomer 3 having a thickness of 2 mm was set in the casing by simultaneous molding. A medical cap was manufactured.
[0033]
(Comparative Example 1)
Cylindrical plugs made of elastomer 3 and having a thickness of 7 mm were respectively set in a casing by simultaneous molding to produce a medical cap.
[0034]
(Comparative Example 2)
A cylindrical stopper made of butadiene rubber and having a thickness of 7 mm was set in a casing by insert molding to produce a medical cap.
[0035]
The caps of the above Examples and Comparative Examples were subjected to resistance measurement against needle stick / needle removal under the following conditions, a self-sealing test, and a holding force test. The average values and the results are shown in Table 1 below. In each test, 10 specimens were used, and a new test needle was used for each specimen. The following three types of needles were used for the test.
Needle 1 Terumo plastic needle, TS-A400LK
Needle 2 JMS plastic needle, JY-A600CNJ
Needle 3 JMS stainless steel needle, JY-A200CN
[0036]
(Measurement of resistance against needle stick and needle removal)
Using the Shimadzu Autograph S-500D model, the maximum resistance value (kgf) when the test needle is allowed to enter the central portion at a speed of 200 mm / min and the maximum resistance value (kgf) when extracting the test needle The average value was measured. The smaller the number is, the easier it is to handle as a cap, indicating good results.
[0037]
(Self-sealing test)
Each sample was welded to the mouth of an infusion bottle, and the sample set as shown in Fig. 8 was hung with a lifting tool for 2 hours. The test needle with the tube end sealed was pulled out, causing liquid leakage in 1 minute. The amount (cc / min) was measured and the average value was shown. In the figure, 1 denotes a cap, 10 denotes an infusion container, 11 denotes an air vent hole, and 12 denotes a water leak check location. The smaller the value, the less liquid leakage and the better.
[0038]
(Retention force test)
Each sample was welded to the mouth of an infusion bottle, and a 1 kg weight was suspended for 6 hours on the set as shown in FIG. 9 and the needle was not removed. Shown the number of things. In the figure, 1 is a cap, 10 is an infusion container, 11 is an air vent hole, and 13 is a 1 kg weight. The larger the value, the better the result. If the weight does not drop at all, the evaluation is 10.
[0039]
[Table 1]

[0040]
As can be seen from Table 1, each of the laminated examples is better than the plastic needle and the metal needle, as compared with Comparative Example 1 consisting of one layer of thermoplastic elastomer plug. The effect is clearly recognized. In particular, Examples 2 and 4 in which the shape of the plug body was a polygonal column showed particularly remarkable effects. Further, compared with Comparative Example 2 which is a single layer rubber stopper, the resistance to needle sticking and needle pulling is small, so that handling is easy. Therefore, the medical cap of the present invention can simplify the manufacturing process, has excellent holding power against needle removal, and eliminates needle dropout and chemical leakage.
[0041]
【The invention's effect】
The present invention is a medical cap having a stopper formed by laminating only a thin layer composed of any one of a thermoplastic elastomer, a gel resin, low-density polyethylene, and a mixture obtained by kneading these with rubber. Thus, a medical cap having improved holding force and restoring force against the needle and excellent in holding force against needle removal and resealability after needle removal can be provided.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a general molding process of rubber.
FIG. 2 is a flowchart showing a general molding process of resin.
FIG. 3 is a cross-sectional view of the medical cap of the present invention in a state where a load is applied to the pierced needle.
FIG. 4 is a cross-sectional view of the cap of the present invention with the needle being removed.
FIG. 5 is a cross-sectional view of a plug body showing one embodiment of a laminated form of plug bodies used in the medical cap of the present invention.
FIG. 6 is a cross-sectional view of a plug body showing another embodiment of a laminated form of plug bodies used in the medical cap of the present invention.
FIG. 7 is a partial cross-sectional perspective view of the medical cap of the present invention.
FIG. 8 is an experimental schematic diagram of a self-sealing test.
FIG. 9 is an experimental schematic diagram of a holding force test.
[Explanation of symbols]
1 Cap 2 Plug body 3 Casing

Claims (4)

A medical cap comprising at least a casing and a plug,
The plug body is composed of only a plurality of thin layers, each of the thin layers is composed of only a thermoplastic elastomer, and at least one pair of adjacent thin layers among the thin layers have different elastic moduli. A medical cap characterized by.   The medical cap according to claim 1, wherein the thin layer has a thickness of 1 mm or more and 3 mm or less.    The medical cap according to claim 1 or 2, wherein the bottom surface shape of the plug body is any one of a polygonal shape, a flower shape, and a star shape.    A medical infusion container using the medical cap according to any one of claims 1 to 3.

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