JP5013516B2 - Medical rubber member, sterilized medical rubber member, and rubber composition - Google Patents

Description

  The present invention relates to a medical rubber member, a sterilized medical rubber member, and a rubber composition. More specifically, the present invention relates to a medical rubber member that is not easily deteriorated by radiation sterilization by irradiation of γ rays or the like, irradiation of γ rays or the like. The present invention relates to a sterilized medical rubber member and a rubber composition used for producing a medical rubber member obtained by radiation sterilization treatment according to the above.

  Conventionally, a medical rubber member or a medical resin member (hereinafter referred to as a medical member) formed of a rubber material or a resin material or the like instead of a metal material is used in a medical device or the like. As such a medical rubber member, for example, a medical rubber button or a medical rubber cap for closing a chemical injection port of a chemical liquid bottle, a blood injection circuit such as an artificial heart, a body fluid circuit such as artificial dialysis, or the like is provided in a mixed injection tube. Examples thereof include medical rubber buttons or medical rubber caps, and these medical rubber buttons or medical rubber caps include needle insertion plugs that are inserted with injection needles and the like. On the other hand, examples of the medical resin member include a catheter, a tube, a blood transfusion bag, a blood bag, and the like.

  These medical members are usually sterilized at the final stage of manufacture or prior to use. Examples of the sterilization treatment include high-pressure steam sterilization treatment for sterilizing medical members at high temperature and high pressure, ethylene oxide sterilization treatment for treating medical members with ethylene oxide, and radiation sterilization treatment for irradiating medical members with radiation. It is done. Among these sterilization treatments, radiation sterilization treatments that have a wide range of application, can ensure safety after sterilization treatments, and can sufficiently sterilize medical members have recently been adopted. It is coming.

  However, when a medical member is sterilized by radiation sterilization treatment, particularly when the medical member is sufficiently sterilized with a high dose, the physical properties of the rubber material or resin material constituting the medical member changes, and the medical member May deteriorate. As a medical member for the purpose of suppressing deterioration due to radiation irradiation, for example, “a polyfunctional triazine compound in a ratio of 0.01 to 20 parts by weight of a polymer to be used in a living body in a range of 0.01 to 20 parts by weight” Patent Document 1 describes a medical material that can be sterilized by radiation, which comprises a composition containing the same.

JP 2003-965 A

  The present invention relates to a medical rubber member that is not easily deteriorated by radiation sterilization by irradiation with gamma rays, a sterilized medical rubber member that has been subjected to radiation sterilization by irradiation with gamma rays, and irradiation with gamma rays. An object of the present invention is to provide a rubber composition used for producing a medical rubber member which is not easily deteriorated even if radiation sterilization is performed.

As means for solving the problems,
A medical rubber comprising a rubber composition containing 100 parts by mass of silicone rubber and 20 parts by mass or more and 45 parts by mass or less of anhydrous silicic acid, and containing no silver ion-containing inorganic antibacterial agent. A sterilized medical rubber cap or medical rubber button formed by subjecting a member to radiation sterilization treatment, and the rate of change in tear strength before and after radiation sterilization treatment in which γ-rays are irradiated at a dose of 50 kGy is -25% or more 0 % , A sterilized medical rubber cap or a medical rubber button ,
The sterilized medical rubber cap or medical use according to claim 1, characterized in that the silicic anhydride contains at least 95% by weight silicon dioxide and at most 5% by weight water. Rubber button ,
Claim 3 is the sterilized medical rubber cap or medical rubber button according to claim 1 or 2 , wherein the silicic acid anhydride has a primary particle size of 0.001 µm to 10 µm .
The sterilized medical rubber cap according to any one of claims 1 to 3 , wherein the silicic acid anhydride has an apparent specific gravity of 40 g / L or more and 70 g / L or less. Or a medical rubber button ,
The sterilization according to any one of claims 1 to 4 , wherein the rubber composition does not contain a polyether-modified silicone oil or a carbinol-modified silicone oil as a hydrophilicity imparting agent. It is a finished medical rubber cap or a medical rubber button .

  The medical rubber member according to the present invention is formed by molding a rubber composition containing 100 parts by mass of silicone rubber and 20 parts by mass or more and 45 parts by mass or less of silicic acid anhydride. The physical properties and the like do not change greatly even when irradiated with radiation such as. Therefore, according to the present invention, it is possible to provide a medical rubber member that is not easily deteriorated even by radiation sterilization by irradiation with γ rays or the like, and is sterilized that has been subjected to radiation sterilization treatment by irradiation with γ rays or the like. A medical rubber member can be provided.

  In addition, when the rubber composition according to the present invention is used as a medical rubber member, the physical properties and the like of the rubber composition are not greatly changed even when irradiated with radiation such as γ rays in the radiation sterilization treatment. It is used to manufacture a medical rubber member that is not easily deteriorated even by radiation sterilization by irradiation. Therefore, according to the present invention, it is possible to provide a rubber composition used for producing a medical rubber member which is not easily deteriorated even by radiation sterilization by irradiation with γ rays or the like.

  First, the rubber composition according to the present invention will be described. This rubber composition contains 100 parts by mass of silicone rubber and 20 parts by mass or more and 45 parts by mass or less of silicic acid anhydride. When the above-mentioned mass proportion of silicic acid anhydride and silicone rubber is contained, when used as a medical rubber member, the physical properties of the medical rubber member greatly change even when irradiated with radiation such as γ-rays in the radiation sterilization process. Can be prevented. As one of the reasons, for example, even if silicic acid anhydride does not cover the entire surface of the medical rubber member, the silicic acid contained in the medical rubber member causes the radiation to the inside of the medical rubber member. It is conceivable that the invasion and / or diffusion of oxygen molecules can be effectively prevented, so that the decomposition of the silicone rubber is suppressed and the radiation resistance of the medical rubber member is improved. Therefore, the rubber composition according to the present invention is suitably used for producing a medical rubber member.

The silicone rubber contained in the rubber composition has an average composition formula: R _n Sio _{(4-n) / 2} (R is a substituted or unsubstituted monovalent hydrocarbon group, preferably having 1 to 12 carbon atoms. A monovalent aliphatic hydrocarbon group, more preferably a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, and n is 1.8 to 2.5, preferably 2.0 to 2.2. An organopolysiloxane represented by () can be preferably mentioned.

  Examples of R include alkyl groups such as methyl, ethyl, propyl, butyl, hexyl and dodecyl, cycloalkyl such as cyclohexyl, vinyl, allyl, butenyl and hexenyl. Alkyl groups such as alkenyl groups, phenyl groups and tolyl groups, aralkyl groups such as β-phenylpropyl groups, and some or all of the hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms or cyano groups. Chloromethyl group, trifluoropropyl group, cyanoethyl group and the like.

  The organopolysiloxane preferably has at least two alkenyl groups in the molecule, that is, the R is preferably an alkyl group and an alkenyl group, and particularly preferably a methyl group and a vinyl group. The ratio of the alkyl group to the alkenyl group is preferably 98 to 99.999 mol% for the alkyl group and 0.001 to 2 mol% for the alkenyl group.

  Examples of the organopolysiloxane containing an alkyl group and an alkenyl group include alkyl vinyl polysiloxane and / or dialkyl polysiloxane. When the rubber composition contains such a silicone rubber, the medical rubber member is excellent in chemical resistance, safety, rubber elasticity and the like when used as a medical rubber member. Among these, dimethylpolysiloxane and the like are preferable as the silicone rubber having no alkenyl group, and methylvinylpolysiloxane and the like are preferable as the silicone rubber having an alkenyl group.

  The degree of polymerization of the organopolysiloxane is preferably 500 or more and 20,000 or less, and particularly preferably 5,000 or more and 15,000 or less. When the organopolysiloxane has a degree of polymerization in the above range, the mechanical strength of the medical rubber member is improved. The degree of polymerization of the organopolysiloxane can be measured by gel permeation chromatography (GPC: Gel Permeation Chromatography) as a standard polystyrene equivalent molecular weight.

  Silicone rubber may be produced as appropriate, or a commercially available product may be used. As a commercial item, for example, trade name “KE-530U” (manufactured by Shin-Etsu Chemical Co., Ltd., degree of polymerization of about 8,000), trade name “SH1123U” (manufactured by Dow Corning Co., Ltd., degree of polymerization of about 8,000), And trade name “TSE 211-3U” (manufactured by GE Toshiba Silicone Co., Ltd., degree of polymerization of about 8,000).

  One kind of silicone rubber may be contained in the rubber composition, or two or more kinds may be contained in the rubber composition.

The silicic acid anhydride contained in the rubber composition according to the present invention may be referred to as dry silica or dry process silica, and different silicons share all oxygen in the tetrahedral structure of SiO _4. It has a three-dimensionally linked molecular structure (see, for example, “Chemical Dictionary” (Tokyo Kagaku Dojin)). The silicic anhydride usually has a water content of at most 5% by weight and a silicon dioxide content of at least 95% by weight. Silica anhydride preferably has a water content of at most 3% by mass because it can effectively prevent changes in physical properties and the like due to radiation irradiation. The water content of silicic acid was expressed as a percentage obtained by heating silicic acid to 150 ° C. for 1 hour and dividing the decrease in mass before heating and mass after heating by the mass after heating. Value.

  Anhydrous silicic acid has a smaller apparent specific gravity than hydrous silicic acid called wet silica, and usually has an apparent specific gravity of 40 to 70 g / L. When the anhydrous silicic acid has an apparent specific gravity in the above range, the mechanical strength of the medical rubber member is improved. The apparent specific gravity of silicic acid anhydride is a value obtained by calculating from its mass and volume after putting silicic acid anhydride into a graduated cylinder and tapping on the basis of the measurement method defined in ISO787 / 11.

Silicic anhydride preferably has a BET specific surface area of 100 m ² / g or more and 400 m ² / g or less, and particularly preferably 250 m ² / g or more and 350 m ² / g or less. When the silicic acid anhydride has a BET specific surface area within the above range, no change in appearance such as white turbidity will occur with respect to radiation sterilization treatment, and mechanical properties such as tearing strength and hardness will not be significantly reduced. can do. The BET specific surface area is a value measured by the BET one-point method which is measured by the nitrogen gas adsorption amount.

  The primary particle size of silicic anhydride is preferably 0.001 μm or more and 10 μm or less, and particularly preferably 0.01 μm or more and 1 μm or less. When the anhydrous silicic acid has a primary particle diameter in the above range, it can be uniformly dispersed in the silicone rubber described later, and the mechanical properties when used as a medical rubber member are improved. The primary particle diameter is a value measured by a swelling compression method.

  Silicic anhydride is usually produced by a dry method. The dry method is a method of generating finely powdered silicic acid particles at a high temperature of 1000 ° C. or higher, and includes a combustion method and a heating method. The combustion method is a method in which vaporized silicon tetrachloride and hydrogen are mixed and combusted in air at a temperature range of 1000 ° C. to 1200 ° C., and fine particulate silicic acid can be produced. . The heating method is a method in which SiO vapor generated by heating and reducing silica sand and coke in an arc furnace is oxidized with oxygen in the air, and fine particulate silicic acid can be produced.

  Silicic anhydride may be produced as appropriate, or a commercially available product may be used. Examples of commercially available products include silicic anhydride produced by a combustion method such as trade name “Aerosil” (manufactured by DEGUSSA or Nippon Aerosil Co., Ltd.) and trade name “Cab-O-Sil” (manufactured by Cabot). Examples thereof include silicic acid anhydride produced by a heating method such as a trade name “Fransil” (manufactured by Fransil), a trade name “Arc Silica” (manufactured by PPG Inc), and the like.

  One kind of silicic acid anhydride may be contained in the rubber composition, and two or more kinds may be contained in the rubber composition.

  Silica anhydride is preferably contained in a proportion of 20 to 45 parts by mass with respect to 100 parts by mass of the silicone rubber, and contained in a proportion of 30 to 45 parts by mass. Is particularly preferred. When silicic anhydride is contained in the rubber composition in the above-mentioned range, when a medical rubber member is used, the physical properties of the medical rubber member and the like are effectively prevented from being significantly reduced by radiation irradiation. Can do.

  In addition to the silicic anhydride and the silicone rubber, the rubber composition may contain, for example, various additives that are usually blended in a rubber-containing composition. Specific examples of various additives include, for example, a crosslinking agent, a filler, an ultraviolet absorber, a plasticizer, a colorant, an antistatic agent, a heat stabilizer, an antioxidant, a light stabilizer, a flame retardant, a lubricant, and an oxidation agent. Examples thereof include an inhibitor, an antiaging agent, a reaction aid, a reaction inhibitor, and a resin. As the crosslinking agent, there is no limitation on the curing mechanism as long as it vulcanizes and cures the silicone rubber by using radical reaction, addition reaction, condensation reaction, etc. that cause crosslinking in the silicone rubber. Various crosslinking agents (also referred to as curing agents) can be used. Examples of the crosslinking agent include alkyl peroxides such as di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and alkyl peroxides such as dicumyl peroxide. As an addition reaction curing agent that is a kind of crosslinking agent, for example, an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to a silicon atom in one molecule and a platinum series Examples include a combination with a catalyst, and examples of the condensation curing agent which is a kind of a crosslinking agent include a combination of a polyfunctional alkoxysilane or siloxane and an organometallic acid salt. The blending amount of the cross-linking agent is selected from the range of blending amounts normally selected for silicone rubber. The various additives other than the crosslinking agent can be used without particular limitation.

  The rubber composition comprises silicic anhydride, silicone rubber, and various additives as required, for example, a mixing roll, a pressure kneader, a roller mill, a Banbury mixer, a two roll, a three roll, a homogenizer, a ball mill, and a bead mill. Etc., and kneading at room temperature or under heating until the silicic anhydride, silicone rubber and various additives are uniformly mixed. The rubber composition may be produced as appropriate, or a commercially available product may be used.

  As described above, the rubber composition according to the present invention is a medical rubber member, in particular, radiation sterilization treatment, because the change in physical properties and the like is small even when irradiated with radiation such as γ rays in the radiation sterilization treatment, It is suitably used for producing a medical rubber member to be pierced with an injection needle.

  Next, the medical rubber member according to the present invention will be described. The medical rubber member according to the present invention may be a rubber member that is attached to a medical device. For example, a medical rubber button or a medical rubber cap that closes a chemical liquid injection port of a chemical liquid bottle, a pipe in a blood circuit, or the like Examples thereof include a medical rubber button or a medical rubber cap provided in the mixed injection tube, and further a needle piercing plug or the like which is a medical rubber button or medical rubber cap or the like and is inserted with an injection needle or the like. In this invention, the injection needle may be any needle that extracts or injects a drug or blood, for example, a needle attached to a syringe, an indwelling needle at least part of which is indwelled in a patient's body, or the like, or Examples thereof include a needle attached to a blood bag or an infusion bag.

  The medical rubber member may have any shape depending on the shape and size of the medical device (for example, a chemical solution bottle or a mixed injection tube) to be mounted, in particular, a mounting portion (for example, a chemical solution inlet or a chemical solution injection portion) of the medical device. And adjusted to an arbitrary size.

  This medical rubber member is manufactured using the rubber composition containing 100 parts by mass of silicone rubber and 20 parts by mass or more and 45 parts by mass or less of silicic anhydride. For example, 100 parts by mass of silicone rubber and 20 parts by mass Manufactured by molding the rubber composition containing not less than 45 parts by mass and not more than 45 parts by mass of silicic anhydride. The method for molding the rubber composition is not particularly limited, and examples thereof include known molding methods, for example, molding methods such as extrusion molding, injection molding, and cast molding. When the medical rubber member is formed of a rubber composition containing silicic anhydride, even if irradiated with radiation such as γ rays, the physical properties can be largely prevented from changing, and the medical rubber member deteriorates. It becomes difficult.

  Therefore, the medical rubber member according to the present invention contains silicone rubber and silicic anhydride. The silicone rubber contained in the medical rubber member is a silicone rubber similar to the silicone rubber contained in the rubber composition or a higher molecular weight silicone rubber in which the silicone rubbers are crosslinked. The silicic acid anhydride contained in the medical rubber member is silicic acid anhydride similar to the silicic acid anhydride contained in the rubber composition. In the medical rubber member according to the present invention, silicone rubber and silicic anhydride may be contained independently of each other, or may be contained as aggregates or composites thereof.

  The medical rubber member according to the present invention preferably has a JIS A hardness of 25 or more and 40 or less, and particularly preferably 30 or more and 35 or less. When the medical rubber member has the JIS A hardness in the above range, the sealing performance is improved, and a part of the medical rubber member is missing and / or dropped when the needle is inserted and pierced. can do. The JIS A hardness can be measured by a measuring method defined in JIS K6249.

  The medical rubber member according to the present invention preferably has a tear strength of 25 kN / m or more and 35 kN / m or less, particularly preferably 26 kN / m or more and 33 kN / m or less. When the medical rubber member has a tear strength in the above range, it is possible to greatly reduce the loss and / or dropout of a part of the medical rubber member when the needle is inserted and punctured. The tear strength can be measured by a measurement method defined in a measurement method (crescent type) defined in JIS K6249.

The medical rubber member according to the present invention is subjected to a radiation sterilization treatment for irradiating radiation such as γ rays after being manufactured into a desired shape by the molding method and / or before use. The radiation sterilization treatment may be performed by a conventional method. In order to sufficiently sterilize the medical rubber member, for example, radiation such as γ rays may be irradiated at an irradiation dose of 20 kGy or more and 50 kGy or less.

The medical rubber member thus subjected to radiation sterilization treatment, that is, the sterilized medical rubber member according to the present invention contains anhydrous silicic acid and silicone rubber, and has physical properties in the medical rubber member before radiation sterilization treatment. Compared to the above, the rate of decrease in physical properties is small. For example, the JIS A hardness of a sterilized medical rubber member irradiated with γ rays at an irradiation dose of 50 kGy has a rate of change of about 0% or more and about 25% or less with respect to the JIS A hardness of the medical rubber member before radiation sterilization treatment. The range is preferably about 0% to about 20%, and particularly preferably about 0% to about 15%. Further, the tensile strength of the sterilized medical rubber member irradiated with γ rays at an irradiation dose of 50 kGy is such that the rate of change with respect to the tensile strength of the medical rubber member before the radiation sterilization treatment is about −10% or more and about 0% or less. It is a range, Preferably it is the range of about -8% or more and about 0% or less. The elongation of the sterilized medical rubber member irradiated with γ-rays at an irradiation dose of 50 kGy is in a range where the rate of change relative to the elongation of the medical rubber member before the radiation sterilization treatment is about −30% to about 0%. Furthermore, the tear strength of the sterilized medical rubber member irradiated with γ rays at an irradiation dose of 50 kGy is such that the rate of change with respect to the tear strength of the medical rubber member before the radiation sterilization treatment is about −25% to about 0%. The range is preferably about −20% or more and about 0% or less, and particularly preferably about −17% or more and about 0% or less. Here, JIS A hardness and tear strength can be measured by the above methods, and tensile strength and elongation can be measured by the measurement methods defined in the measurement method defined in JIS K6249.

  Since the medical rubber member according to the present invention is formed by molding a rubber composition containing silicic anhydride and silicone rubber, the physical properties and the like of the medical rubber member can be obtained even when irradiated with radiation such as γ rays in radiation sterilization treatment. It does not change significantly and is not easily degraded. As one of the reasons, for example, as described above, even if silicic anhydride does not cover the entire surface of the medical rubber member, the silicone rubber by radiation irradiation can be used with the silicic acid contained in the medical rubber member. It is conceivable that the radiation resistance is improved by suppressing the decomposition of. As a result, even when the medical rubber member according to the present invention is subjected to radiation sterilization treatment, that is, the sterilized medical rubber member according to the present invention can prevent the occurrence of cracks and the like in the medical rubber member. The functions required of the medical rubber member such as the exudation of the chemical solution and the prevention of the contamination of the chemical solution can be sufficiently maintained.

  When the medical rubber member according to the present invention is used as a needle puncture plug, the medical rubber member has a characteristic that it is difficult to deteriorate even when subjected to radiation sterilization treatment. It is possible to prevent a part of the medical rubber member from being lost, dropped off or peeled off from the medical rubber member. As a result, even if the medical rubber member according to the present invention is subjected to radiation sterilization treatment, that is, the sterilized medical rubber member according to the present invention can be placed in the chemical solution bottle even after the necessary amount of chemical solution is taken out from the chemical solution bottle. It is possible to achieve the object of maintaining the sealed state of the stored chemical solution and preventing the chemical solution from exuding and chemical solution contamination.

  In addition, since the medical rubber member according to the present invention is not easily deteriorated even when irradiated with radiation such as γ-rays in this way, for example, radiation sterilization treatment is performed after molding of the rubber composition and before use. Can be done multiple times.

  An embodiment of a medical rubber member according to the present invention will be described with reference to the drawings. One embodiment of the medical rubber member is a medical rubber cap 1 that closes a chemical liquid injection port 31 such as a chemical liquid bottle 30 as shown in FIGS. 1 and 2. The medical rubber cap 1 includes a rubber cap main body 10 that is press-fitted into a chemical liquid injection port 31 of the chemical liquid bottle 30 to close the chemical liquid injection port 31, and a head 11 that protrudes in the circumferential direction on the upper part of the rubber cap main body 10. This is an example of a needle pierce that is provided and through which the injection needle 20 penetrates. The rubber cap body 10 in the medical rubber cap 1 is formed in a cylindrical shape according to the cross-sectional shape of the chemical liquid inlet 31 in the chemical liquid bottle 30 to be attached, and the diameter thereof is slightly larger than the inner diameter of the chemical liquid inlet 31. The dimensions have been adjusted. The head 11 in the medical rubber cap 1 is formed in a disk shape, and the diameter thereof is adjusted to be approximately the same as the outer diameter of the collar portion 32 provided in the chemical liquid inlet 31 in the chemical liquid bottle 30.

This medical rubber cap 1 is formed by injection-molding the rubber composition containing anhydrous silicic acid and silicone rubber, and each contains one or more kinds of anhydrous silicic acid and silicone rubber. The medical rubber cap 1 has a JIS A hardness of 30 to 35. Prior to use, the medical rubber cap 1 is irradiated with, for example, γ rays at an irradiation amount of 22.2 kGy to form a sterilized medical rubber cap 2. As described above, the sterilized medical rubber cap 2 does not greatly change its physical properties with respect to the physical properties of the medical rubber cap 1. For example, the sterilized medical rubber cap 2 is sterilized by irradiating γ rays with an irradiation dose of 50 kGy. Even so, the JIS A hardness, tensile strength, elongation and tear strength are within the above-mentioned ranges.

  As shown in FIG. 2, the sterilized medical rubber cap 2 obtained by sterilizing the medical rubber cap 1 has the rubber cap body 10 at the chemical liquid injection port 31 of the chemical liquid bottle 30 and the buttocks of the chemical liquid injection port 31. It press-fits until 32 and the bottom face of the head 11 contact | abut, and is mounted | worn with the chemical | medical solution bottle 30. FIG. And when taking out the chemical | medical solution 33 accommodated in the chemical | medical solution bottle 30, as shown in FIG. 2, the injection needle 20 is stabbed into the sterilized medical rubber cap 2, and the injection needle 20 is sterilized medical rubber cap. 2, for example, the drug solution bottle 30 is tilted or overturned, and the drug solution 33 is extracted from the injection needle 20. Thereafter, the injection needle 20 is removed from the sterilized medical rubber cap 2. In this way, a series of operations are completed, but the medical rubber cap 1 is formed by molding a rubber composition containing anhydrous silicic acid and silicone rubber, so that it does not deteriorate even when subjected to radiation sterilization treatment. Hard to deteriorate. Accordingly, the sterilized medical rubber cap 2 that has been sterilized by radiation before use of the medical rubber cap 1 does not greatly change its physical properties relative to the medical rubber cap 1. In addition to preventing cracks in the cap 2 and the like, the injection needle 20 can be easily passed through the sterilized medical rubber cap 2, and the necessary amount is avoided while exuding the drug solution 33 and contaminating the drug solution 33. The chemical solution 33 can be taken out.

  Furthermore, the sterilized medical rubber cap 2 can prevent a part of the sterilized medical rubber cap 2 from being lost, dropped off, or peeled off from the sterilized medical rubber cap 2 even if the injection needle 20 is inserted. Therefore, even after the required amount of the chemical solution 33 is taken out from the chemical solution bottle 30, the state in which the chemical solution 33 contained in the chemical solution bottle 30 is kept sealed prevents exudation of the chemical solution 33, contamination of the chemical solution 33, and the like. Aim can be achieved.

  Further, the medical rubber cap 1 and the sterilized medical rubber cap 2 can be subjected to radiation sterilization multiple times.

  Another embodiment of the medical rubber member according to the present invention will be described with reference to the drawings. Another embodiment of the medical rubber member is a medical rubber button 3 that closes the drug solution injection portion 43 such as the mixed injection tube 40 as shown in FIGS. 3 and 4. The medical rubber button 3 is, for example, a medical rubber cap that is attached to a mixed injection tube 40 interposed in pipes 41 and 42 that constitute a part of a blood circuit such as an artificial heart. This is an example of a needle puncture needle that is press-fitted into the chemical liquid injection part 43 of the part to close the chemical liquid injection part 43 and through which the injection needle 20 passes. This medical rubber button 3 is formed in a disc shape according to the cross-sectional shape of the chemical injection part 43 in the mixed injection tube 40 to be attached, and its diameter is slightly smaller than the inner diameter of the chemical injection part 43 in the mixed injection pipe 40 to be attached. It has been adjusted to a large size.

This medical rubber button 3 is formed by injection molding the rubber composition containing anhydrous silicic acid and silicone rubber, and each contains one or more kinds of anhydrous silicic acid and silicone rubber. The medical rubber button 3 has a JIS A hardness adjusted to 30 or more and 35 or less. Prior to use, the medical rubber button 3 is irradiated with, for example, γ rays at an irradiation amount of 22.2 kGy to form a sterilized medical rubber button 4. As described above, the sterilized medical rubber button 4 does not greatly change its physical property with respect to the physical property of the medical rubber button 3. For example, the sterilized medical rubber button 4 is sterilized by irradiating γ rays with an irradiation dose of 50 kGy. Even so, the JIS A hardness, tensile strength, elongation and tear strength are within the above-mentioned ranges.

  As shown in FIG. 4, the sterilized medical rubber button 4 obtained by sterilizing the medical rubber button 3 is press-fitted into the drug solution injection portion 43 of the mixed injection tube 40 and attached to the mixed injection tube 40. When injecting a chemical solution (not shown) or the like into the mixed injection tube 40 or extracting a body fluid or the like flowing through the mixed injection tube 40, as shown in FIG. Is inserted into the sterilized medical rubber button 4 to inject a drug solution or the like from the injection needle 20 into the drug solution injection portion 43 of the mixed injection tube 40 or extract a body fluid or the like flowing through the mixed injection tube 40. Thereafter, the injection needle 20 is removed from the sterilized medical rubber button 4. In this way, a series of operations are completed, but the medical rubber button 3 is formed by molding a rubber composition containing anhydrous silicic acid and silicone rubber, so that it does not deteriorate even when subjected to radiation sterilization treatment. Hard to deteriorate. Accordingly, the sterilized medical rubber button 4 that has been subjected to radiation sterilization treatment before the use of the medical rubber button 3 does not greatly change its physical properties relative to the medical rubber button 3. The button 4 can be prevented from cracking and the like, and the syringe needle 20 can be easily penetrated through the sterilized medical rubber button 4 to avoid exudation and contamination of blood flowing through the mixed injection tube 40. Therefore, a necessary body fluid or the like can be injected into the mixed injection tube 40 or a body fluid flowing through the mixed injection tube 40 can be extracted.

  Further, the sterilized medical rubber button 4 can prevent a part of the sterilized medical rubber button 4 from being lost, dropped off, or peeled off from the sterilized medical rubber button 4 even if the injection needle 20 is inserted. Therefore, even after injecting the necessary medicinal solution into the mixed injection tube 40 or extracting the body fluid flowing through the mixed injection tube 40, the blood flowing through the mixed injection tube 40 is maintained sealed and distributed through the mixed injection tube 40. The purpose of preventing exudation and contamination of blood and the like can be achieved.

  Further, the medical rubber button 3 and the sterilized medical rubber button 4 can be subjected to radiation sterilization processing a plurality of times.

  The medical rubber member according to the present invention is not limited to the above-described embodiments, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, the medical rubber cap 1 and the medical rubber button 3 are formed in a cylindrical shape or a disk shape, but in the present invention, the medical rubber member is not limited to a cylindrical shape or a disk shape, The shape may be a rectangle, a polygon, a streamline, or the like.

  The medical rubber cap 1 and the sterilized medical rubber cap 2 include a rubber cap body 10 and a head portion 11. In the present invention, the medical rubber cap and the sterilized medical rubber cap have a head portion. You may comprise with the rubber cap main body which does not have. The medical rubber button 3 and the sterilized medical rubber button 4 are formed in a disc shape. In the present invention, the medical rubber button and the sterilized medical rubber button protrude in the circumferential direction on the upper part. You may be equipped with the head to do.

  The medical rubber cap 1, the sterilized medical rubber cap 2, the medical rubber button 3, and the sterilized medical rubber button 4 are all needle stabs that are inserted with an injection needle or the like. The rubber member for medical use may be a stopper that simply closes the drug solution injection part of the mixed injection tube in the drug solution injection port of the drug solution bottle, the blood circuit such as an artificial heart, or the body fluid circuit such as artificial dialysis, etc. It may be a medical rubber member that is not stabbed, that is, a kneeless type. The needleless type medical rubber member is provided with a slit that penetrates in the axial direction and allows the medicine to be taken out and injected, for example, a medical rubber button or a medical rubber cap that closes the chemical liquid inlet of the chemical bottle. And a medical rubber button or a medical rubber cap provided on a mixed injection tube in a blood circuit such as an artificial heart or a body fluid circuit such as artificial dialysis.

(Examples 1-5 and Comparative Examples 1-3)
Rubber compositions 1 to 5 (Examples 1 to 5) and rubber compositions 6 to 8 (Comparative Examples 1 to 3) having the following compositions were respectively injection-molded, and “dumbbell-shaped test pieces” defined in JIS K6249. Several were produced. A part of each dumbbell-shaped test piece produced in this way was irradiated with γ rays emitted from cobalt 60 on the upper surface and the lower surface by a dose of 25 kGy (total 50 kGy ) to obtain irradiated test pieces. Using a dumbbell-shaped test piece (corresponding to a medical rubber member in the present invention) and an irradiated test piece (corresponding to a sterilized medical rubber member in the present invention), conforming to the measurement method prescribed in JIS K6249 JIS A hardness, tensile strength, elongation and tear strength are measured, and the difference between the measured value of the irradiated specimen and the measured value of the dumbbell specimen is divided by the measured value of the dumbbell specimen. The rate (%) was calculated. The results are shown in Table 1.

(Rubber composition 1)
100 parts by mass of methyl vinyl polysiloxane (degree of polymerization about 8,000, vinyl group content 0.25 mol%), silicic anhydride (BET specific surface area 200 m ² / g, apparent specific gravity about 50 g / L, primary particle diameter About 12 nm, trade name “Aerosil 200” manufactured by Nippon Aerosil Co., Ltd. 32.5 parts by mass, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane 0.7 part by mass (rubber composition) 2)
100 parts by mass of methyl vinyl polysiloxane (degree of polymerization about 8,000, vinyl group content 0.25 mol%), silicic anhydride (BET specific surface area 110 m ² / g, apparent specific gravity about 50 g / L, primary particle diameter About 16 nm, trade name “Aerosil R972”, manufactured by Nippon Aerosil Co., Ltd. 32.5 parts by mass, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane 0.7 parts by mass (rubber composition) 3)
Methyl vinyl polysiloxane (degree of polymerization about 800, vinyl group content 0.25 mol%) 100 parts by mass, silicic anhydride (BET specific surface area 200 m ² / g, apparent specific gravity about 50 g / L, primary particle diameter about 12 nm , Trade name "Aerosil 200", manufactured by Nippon Aerosil Co., Ltd.) 32.5 parts by mass, methyl hydrogen polysiloxane 4 parts by mass, platinum-based catalyst 5 ppm in terms of platinum
(Rubber composition 4)
Rubber composition in which content of silicic acid anhydride in rubber composition 1 is changed from 32.5 parts by mass to 20 parts by mass (rubber composition 5)
Rubber composition in which content of silicic anhydride in rubber composition 1 is changed from 32.5 parts by mass to 45 parts by mass

(Rubber composition 6)
100 parts by mass of methyl vinyl polysiloxane (degree of polymerization about 8,000, vinyl group content 0.25 mol%), hydrous silicic acid (BET specific surface area 200 m ² / g, secondary particle diameter 18 μm, trade name “Nipsil made of silica” VN-3 ", manufactured by Tosoh Corporation) 42 parts by mass, 0.7 parts by mass of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (rubber composition 7)
Rubber composition wherein the content of silicic acid anhydride in the rubber composition 1 is changed from 32.5 parts by mass to 15 parts by mass (rubber composition 8)
Rubber composition in which content of silicic acid anhydride in rubber composition 1 is changed from 32.5 parts by mass to 50 parts by mass

(Examples 6 to 10 and Comparative Examples 4 to 6)
The rubber compositions 1 to 5 (Examples 6 to 10) and the rubber compositions 6 to 8 (Comparative Examples 4 to 6) are respectively injection molded to produce a plurality of medical rubber caps 1 having the shape shown in FIG. did. A part of the medical rubber cap 1 manufactured in this way is evenly irradiated on the entire surface of the medical rubber cap 1 with gamma rays emitted from the cobalt 60 at an irradiation amount of 39.2 kGy . A sterilized medical rubber cap 2 having the shape shown was produced. Each medical rubber cap 1 and each sterilized medical rubber cap 2 have a rubber cap body 10 having an outer diameter of 5.5 mm and a length of 1.8 mm, and a head 11 having an outer diameter of 8.2 mm and a thickness of 5.3 mm. And had. As shown in FIG. 2, the rubber cap body 10 of each medical rubber cap 1 and each sterilized medical rubber cap 2 is connected to a chemical solution inlet 31 (inner diameter 5.2 mm (outside of the rubber cap main body 10)). The inner diameter was 95%) and the outer diameter was 8.2 mm. As shown in FIG. 2, the medical rubber caps 1 and the sterilized medical rubber caps 2 attached to the drug solution inlets 31 are pierced until they penetrate the injection needle (18G) 20 of the syringe, and then pierced. The injection needle 20 was pulled out. The injection needle 20 was stabbed and pulled out as one cycle, and 10 cycles were performed continuously, and the state of each medical rubber cap 1 and each sterilized medical rubber cap 2 was visually confirmed. This test was performed a plurality of times for each medical rubber cap 1 and each sterilized medical rubber cap 2 and evaluated as follows. In any test, when a part of the medical rubber cap 1 or the sterilized medical rubber cap 2 is missing, does not fall off or peel off, “○”, in at least one test among a plurality of tests, When a part of the medical rubber cap 1 or the sterilized medical rubber cap 2 is missing, dropped or peeled off, “△” indicates that the medical rubber cap 1 or sterilized medical use is used in most of the tests. A case where a part of the rubber cap 2 was missing, dropped or peeled off in the shape of the needle hole of the injection needle was indicated as “x”. The results are shown in Table 2.

FIG. 1 is a schematic perspective view showing a medical rubber cap according to an embodiment of the present invention. FIG. 2 is a schematic sectional view showing a state where an injection needle is inserted into a sterilized medical rubber cap according to an embodiment of the present invention. FIG. 3 is a schematic perspective view showing a medical rubber button according to another embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing a state where an injection needle is inserted into a sterilized medical rubber button according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Medical rubber cap 2 Sterilized medical rubber cap 3 Medical rubber button 4 Sterilized medical rubber button 10 Rubber cap main body 11 Head 20 Injection needle 30 Medicinal solution bottle 31 Medicinal solution injection port 32 Butt portion 33 Medicinal solution 40 Mixed injection tube 41 42 Pipe 43 Chemical solution injection part

Claims (5)

Radiation sterilization treatment for a medical rubber member containing 100 parts by mass of silicone rubber and 20 parts by mass or more and 45 parts by mass or less of silicic acid anhydride and containing a silver ion-containing inorganic antibacterial agent-free rubber composition A sterilized medical rubber cap or a medical rubber button,
A sterilized medical rubber cap or medical rubber button characterized in that the rate of change in tear strength before and after radiation sterilization treatment in which γ rays are irradiated at an irradiation dose of 50 kGy is -25% or more and 0% or less . The sterilized medical rubber cap or medical rubber button according to claim 1, wherein the silicic acid anhydride contains at least 95% by mass of silicon dioxide and at most 5% by mass of water . 3. The sterilized medical rubber cap or medical rubber button according to claim 1, wherein the silicic acid anhydride has a primary particle diameter of 0.001 μm to 10 μm . The sterilized medical rubber cap or medical rubber according to any one of claims 1 to 3, wherein the silicic acid anhydride has an apparent specific gravity of 40 g / L or more and 70 g / L or less. Button . The sterilized medical rubber according to any one of claims 1 to 4, wherein the rubber composition does not contain a polyether-modified silicone oil or a carbinol-modified silicone oil as a hydrophilicity imparting agent. Cap or medical rubber button .

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