JPS58165856A - Medical instrument - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Background of the Invention Technical Field The present invention relates to a medical instrument that can be sterilized by radiation.

More specifically, the present invention relates to a radiation sterilizable medical device comprising a composition comprising a propylene polymer blended with a stabilizer and a nucleating agent.

Zoropyrene polymers are widely used in medical instruments, especially disposable medical instruments such as syringes, needle bases, infusion/blood transfusion sets, and blood sampling instruments due to their rigidity and impact strength. However, propylene polymer products have the disadvantage of deterioration and discoloration during radiation sterilization.

That is, when a zolopyrene polymer is irradiated with radiation of 2 to 4 megarads, decomposition and deterioration reactions occur, resulting in coloring of the product, generation of cracks, and reduction in impact strength. Furthermore, problems such as the elution of stabilizers blended into the polymer for the purpose of preventing oxidation, removing radicals, and other purposes may occur, such as generation of odor and significant coloring.

When the medical device is an injection molded product, the above deterioration due to radiation irradiation is particularly noticeable.

Therefore, several methods for improving the radiation resistance of propylene polymer products have already been reported.

That is, a method of blending various phenol-based, phosphorus-based or sulfur-based compounds as stabilizers with propylene polymer (Japanese Patent Application Laid-Open No. 49-39637), a method of blending hindered amine (Japanese Patent Application Laid-Open No. 55-19199), and A method (US Pat. No. 4,274,932) has been proposed in which a non-quality additive is blended into a propylene polymer having a narrow molecular weight distribution. Although these methods have considerably improved the radiation resistance of propylene polymers, there are still points to be improved.

In other words, methods of blending phenol-based, phosphorus-based, or sulfur-based compounds have practical problems in terms of color resistance and heat deterioration resistance, as well as the phenomenon of elution into the contents that come into contact with the molded product. . For example, the one described in JP-A No. 49-39637 to which tetrakis [methylene (3,5-] tert-butyl hydroxyhydrocinnamate)]methane is added is significantly colored by irradiation with 2.5 megarad gamma rays. 111
13-) IJs(2-methyl-5-tert-butyl-4
-Hydroxyphenol)butane added has insufficient heat resistance after irradiation.
``In the method of adding hindered amine,
Hinder door 1 described in the above Japanese Patent Application Laid-Open No. 55-19199
For example, cepacic acid (2,2,6,6-tetramethyl-4-piperidyl) has problems such as elution of cytotoxic substances and bleeding of the additive onto the surface of molded products over time. be. Furthermore, when a hindered amine is added alone, the molecular weight decreases during molding, resulting in a large decrease in strength.

In addition, the method of blending non-quality additives into a zolopyrene polymer with a narrow molecular weight distribution does not sufficiently prevent deterioration, and there are problems in terms of bleeding of additives, toxicity, etc., and this is not practical.

As described above, all of the methods reported so far have some kind of difficulty, and there are problems in implementing them commercially.

Furthermore, it is common practice to add a nucleating agent to a zolopyrene polymer composition to improve the transparency of the product. However, among the conventionally used nucleating agents, dibenzylidene sorbitol, which has an excellent transparency improvement effect, decomposes when exposed to radiation and generates an odor, so radiation sterilization of medical instruments to which this nucleating agent is added is difficult. There was a problem.

12-10 Purpose of the Invention Accordingly, the purpose of the present invention is to provide a medical instrument made of a zolopyrene polymer that can be commercially sterilized by radiation irradiation.

In other words, the present invention provides a transparent material that retains the characteristics of propylene polymers such as transparency and impact strength even after radiation sterilization, and also satisfies all safety and hygiene issues such as toxicity and odor generation. Its purpose is to provide medical equipment.

(1) Detailed Description of the Invention The present invention consists of medical instruments described in the following items 1 to 13, respectively.

(1) Add 0.01 parts by weight of a hindered amine represented by the following formula mt or [■] as a stabilizer to 100 parts by weight of a propylene polymer having a ratio of weight average molecular weight to number average molecular weight of 5 or less.
~0.4 part by weight and the following formula [■].

0.01 to 0.4 parts by weight of a phenol or its phosphite compound represented by (IV) or [■], and 0.0 parts of a compound represented by the following formula [VI] as a nucleating agent.
A medical device capable of radiation sterilization, characterized in that it is a molded article made of a composition containing 1 to 0.4 parts by weight.

[Dox ox In the above formula, R1 is an alkyl group having 1 to 12 carbon atoms, 15-R2 is an alkyl group having 3 to 12 carbon atoms, Y is a divalent hydrocarbon group having 1 to 18 carbon atoms, or sulfur atom, 2 is a divalent hydrocarbon group having 1 to 8 carbon atoms which may contain a carbonyloxy group, R5 and R6 are alkyl or alkoxy groups having 1 to 8 carbon atoms, hydroxyl group or ).rodane Atom, k is 1~
t is an integer of 1 to 16, m is an integer of 1 to 6, nl and R2 are each independently an integer of 1 to 3, and p is 0 or 1.

(2) The ratio of weight average molecular weight to number average molecular weight is 25 to 48
To 100 parts by weight of the propylene polymer, 0.03 to 0.3 parts by weight of the 16-hydroxylated amine represented by the formula CD or [ID as a stabilizer, and the formula CI [1], [IV] or [ Phenol or its phosphite compound represented by V] 0.02~
0.2 parts by weight and 0.05 to 0.3 parts by weight of the compound represented by the formula [VI] as a nucleating agent. Medical equipment.

(3) The medical device according to the above item 1 or 2, wherein the hindered amine is a compound represented by the formula [ID, where R4 is a methyl group and k is 3 or 4.

(4) The hindered amine has the formula [ID]
The medical device according to item 1 or 2 above, wherein R1 is a methyl group and t is 2.

(5) The phenol compound has the above formula [■], R2 is a t-butyl group (5th position), and R3 is a methyl group (2
The medical device according to any one of the above items 1 to 4, wherein x is a hydrogen atom and m is 1.

(6) The phenol phosphite compound has the above formula [■], R2 is a t-butyl group (5th position), R3 is a methyl group (2nd position), X is a group -P(OC18H37)2,
The medical device according to any one of the above items 1 to 4, wherein m is a compound represented by 1.

(7) The phenol phosphite compound has the above formula [■], R2 is a t-butyl group (5th position), R3 is a methyl group (2nd position), X is a group -P(OC18H37)2,
The medical device according to any one of the above items 1 to 4, wherein Y is a compound represented by the group '; CH-CH2-CH2-CH6.

(8) The phenol compound is R in formula [■]
The medical device according to any one of items 1 to 4 above, wherein 2 and R3 are t-butyl groups (3, 5 positions), and z is a methylene group.

(9) The medical use according to any one of the above items 1 to 8, wherein the nucleating agent is a compound in the formula [VI] in which R5 is a methyl group (4th position) and n is 1. utensils.

01 The medical device according to any one of the above items 1 to 9, wherein the molded product is an injection molded product.

<1]) The injection molded product is a syringe barrel, a needle base of a syringe needle,
The first item is an infusion or blood transfusion set or a blood collection device.
The medical device described in item 0.

(a) 100 parts by weight of a propylene polymer having a ratio of weight average molecular weight to number average molecular weight of 5 or less, and 0.0 parts by weight of a hindered amine represented by the following formula [I] or CII] as a stabilizer.
01 to 0.4 parts by weight, and the following formula [■].

0.01 to 0.4 parts by weight of phenol or its phosphite compound represented by [IV] or [■] and 0.01 part of a compound represented by the following formula [VI] as a nucleating agent
9. A medical device capable of radiation sterilization, characterized in that it is a molded article sterilized by radiation.

In the above formula, R1 is an alkyl group having 1 to 12 carbon atoms, R2 is an alkyl group having 3 to 12 carbon atoms, Y is a divalent hydrocarbon group having 1 to 18 carbon atoms or a sulfur atom, and 2 is A divalent hydrocarbon group having 1 to 8 carbon atoms which may contain a carbonyloxy group, R5 and R6 are alkyl or alkoxy groups having 1 to 8 carbon atoms, a hydroxyl group or a halogen atom, k is 1 to 1
t is an integer of 1 to 16, m is an integer of 1 to 6, n and R2 are each independently an integer of 1 to 3, and p is 0 or 1.

(13) The medical instrument according to item 12 above, wherein the radiation sterilization is R-ray or X-ray sterilization.

The medical device of the present invention, as described above, has the formula mt or [■ ] Hindered amine 0.01~
0.4 parts by weight and the above formula [111:), [IV)
or 0.01 to 0.4 parts by weight of a phenol or its phosphite compound represented by [■], and 0.01 to 0.4 parts by weight of a compound represented by the above formula [■] as a nucleating agent.
It is a molded article made of a composition containing parts by weight.

In the present invention, the Q value is 5 or less, preferably 25 to 4.
8 propylene polymer is used. The Q value indicates the molecular weight distribution, and the smaller the Q value, the narrower the molecular weight distribution. Propylene polymers with a Q value greater than 5 are not suitable for use in the present invention because their impact strength decreases significantly when exposed to radiation. The Q value is controlled by methods known per se. For example, the selection of catalysts used during the production of propylene polymers, the seven-day feed method,
The desired Q can be achieved by selecting polymerization conditions such as polymerization pressure and polymerization temperature, by thermally decomposing the obtained powder during sterilization, and by adding peroxide to decompose it.
A propylene polymer having a certain value is obtained.

The propylene polymer referred to in the present invention includes, in addition to a polymer of zolopylene alone, that is, a propylene homopolymer, a propylene-ethylene copolymer having an ethylene content of 5 to 9 cents by weight or less, and a propylene 23-homopolymer to propylene-ethylene. It includes blends with ethylene copolymers and the ethylene content in the blend is 5 noe cents by weight or less. The copolymer may be either random or block, but a random copolymer is preferred. Zorogylene homopolymer has a high rigidity in molded products, so when manufacturing medical devices that require flexibility, it is necessary to copolymerize with a small amount of ethylene to control the rigidity of the molded product, as described above. is desirable. The appropriate melt flow index (MFR) of the polymer is approximately 5 to 30 Vlomin, depending on the type of product.

For example, for syringe barrels, the ethylene content is 1.5 to 1.5.
3.0 cents by weight, MFRIO ~ 20 is preferable, and the syringe needle and the octopus tube of the infusion set should have an ethylene content of 0 to 30 cents by weight, MFR 6 ~
20 is desirable.

A suitable example of a hindered amine used as a stabilizer is a formula [■] in which R4 is a methyl group and k is 3 to 4.
In the compound, formula [■], R1 is a methyl group, t
Examples include compounds in which 2 is 2. In the present invention, two or more hindered amines having the formula [■] or [ID can also be used in combination. These hindered amines are added in an amount of 0.01 to 0.4, preferably 0.01 to 0.4, preferably 0.01 to 0.4 parts by weight, based on 100 parts by weight of the propylene polymer.
03 to 0.3 parts by weight is blended.

Another preferred example of a stabilizer, phenol or its phosphite compound, is the formula (I[
I], R2 is a t-butyl group (5th position), R3 is a methyl group (2nd position), X is a hydrogen atom, and m is 1, R
2 is a t-butyl group (5th position), R3 is a methyl group (2nd position),
A compound in which X is a group -P(OC18H37)2 and m is 1, in the formula [IV], R2 is a t-butyl group (5th position),
R3 is a methyl group (2nd position), X is a hydrogen atom, Y is a group'';
, CH-CH2-CH2-CH, a compound in which R2 is a t-butyl group (5th position), R5 is a methyl group (2nd position), X is a hydrogen atom, Y is -S-, R2 is t -butyl group (5th position), R5 is a methyl group (2nd position), X is a group -P(O
C18H37)2, Y is a group, CH-CH2-CH2-
Compounds that are CH3, in formula [V], R2 and R
A compound in which 3 is a t-butyl group (3,5 positions), z is a methylene group, R2 and R3 are t-butyl groups (3,5 positions),
Examples include compounds where 2 is a group -CH2CH2C00CH2CH2-te. In the present invention, two or more types of phenols or phosphorous esters thereof having the formulas ClIn to V'J can also be used in combination. These phenols or their phosphite compounds are used in amounts of 0.01 to 0 per 100 parts by weight of propylene polymer.
．． 4 is preferably blended in an amount of 0.03 to 0.3 parts by weight.

A preferable example of the nucleating agent used in the present invention is the formula [■] in which R5 is a methyl group (4th position) and n.

and a compound in which R2 is 1 and p is 1. The nucleating agent is used in an amount of 0.00 parts by weight per 100 parts by weight of the propylene polymer.
01 to 0.4, preferably 0.05 to 0.3 parts by weight.

The composition of the present invention thus obtained has the objectives and objectives of the present invention.
Other additives such as antioxidants, nucleating agents, light stabilizers, ultraviolet absorbers, antistatic agents, neutralizing agents such as metal soaps, dispersants, pigments, etc. may be added within a range that does not inhibit the effect. can.

The medical device of the present invention is produced by melt-kneading the above-mentioned composition in a mixer such as a roll, a Panbury mixer Brabender Zolastograph, or an extruder, and then molding it into a medical device by injection molding or the like. Generally, each additive is blended into a powdered propylene polymer, and after mixing with a suitable mixing device such as a mixer,
It is melt-kneaded in an extruder and pelletized, or directly injection molded without pelletizing. It is preferable that the injection molded product be packaged with a polyester polyethylene laminate film or the like and sterilized by radiation before being shipped as is. Gamma rays or X-rays are used as the radiation, preferably gamma rays from a cobalt-60 ray source. The irradiation amount is 5 megarads or less, preferably 2 to 4 megarads, and excessive irradiation causes deterioration of the molded product. Irradiation may be performed in vacuum, in an inert gas such as nitrogen, or in air, and is carried out at a temperature of 80° C. or lower, preferably room temperature or lower.
j Examples of radiation sterilizable medical instruments obtained by the present invention include, but are not limited to, syringes, injection needles, syringe bases, infusion/blood transfusion sets, blood sampling instruments, etc. .

Next, the present invention will be explained in more detail with reference to Examples and Comparative Test Examples.

Example 1 The hindered amine, phenol or its phosphite compound of the present invention, and a nucleating agent were added to a powdery propylene-ethylene random copolymer in the amounts shown in Table 1, and the mixture was heated in a 30-diameter extruder. (230°C). At that time, the MFR of the pellet (230℃, 2.16
kg) and Q value to the values listed in Table 1, pace l? Uda's MFR selection Ohinokuhexine 25
B (trade name of (2,5-dimethyl-2,5-)(t-butylno or monooxy)hexyne-3] is added,
Predetermined pellets were obtained. The obtained pellets were applied to an injection molding machine 1590B manufactured by Toshiba Machine Service Co., Ltd. to form a 100x100xt square sheet (280°C), and γ-ray irradiation (2.5 megarads) was performed using a cobalt 60 radiation source for evaluation.

Evaluation items included visually determining the degree of coloration after placing the specimen in an 80°C oven for one week, and using a haze meter (
Measurement of haze according to ASTM-D-1003), measurement of energy at 50% failure using a DuPont impact tester manufactured by Toyo Seiki, and the occurrence of cracks or embrittlement when the specimen is placed in a 120℃ oven. days, VF of test piece
R measurement and observation of surface bleed after placing the test piece in an 80° C. oven for one week were carried out.

For the cytotoxicity test, the strip sample was extracted with 3 times the amount of MEM medium at 121°C for 20 minutes, and the toxicity of the extract to HeLa-83 cells was determined using a microscope. 0 indicates that there is no difference from the blank, 1 indicates that the number of dead cells has increased slightly, 2 indicates that all cells are dead, and 3 indicates that all cells are dead. Hemolytic toxicity was determined by immersing a specimen with a surface area of 1,2006 rfL2 in physiological saline at 121°C for 20 minutes, adding rabbit washed red blood cells to the resulting extraction solution, and leaving it at 37°C for 24 hours. I judged it. Those with no difference from the blank are non-toxic ←), those colored a tingling red are weakly toxic cll:)
, Those colored red are labeled as toxic (←), and those colored dark red are labeled as highly toxic. The results are shown in Table 1. In the table, the stabilizer, nucleating agent, and auxiliary agent listed by product name represent the following compounds, respectively.

A compound manufactured by Ciba Geigy Co., Ltd. in the formula [■] where R1 = CH3, and = 3 to 4.

Compound with R1=CH3, t=2 in the product formula [■] of Adeka Argus Chemical Co., Ltd. Chemical name: Bis(2,2,6,6-titrametherbiperidyl) Separate, product formula provided by Sankyo Co., Ltd. Compound [■] 1.1.3-tris(2-methyl-4-hydroxy-5
-tert-butylphenyl) butane product from Dorich Chemical Co., Ltd. Compound of formula [■] Tris(3,5-not-tert-butyl-4-hydroxybenzyl)isocyanurade Adeca-Argus Chemical Co., Ltd. product ICI product Tetrakis [methylene-3 -(3,5-di-t-butyl-4-hydroxyphenyl) f-robionate] methane MT P Yoshitomi Rippyaku product Nomiristyl thiodizolobionate EC Chemicals product Formula [VI] In the formula [VI], R5 is a methyl group (p) and n is 1 □1 compound (1,3,2,4-di-p-methylbenzylidene-sorbitol CI Product from Easy Chemical Co., Ltd. 1.3,2,4-diben-clidene-sorbitol BK Product from Nitto Chemical Co., Ltd. In Table 1 of calcium stearate, Examples 1-(1) to (5) respectively show the cases where the stabilizer and nucleating agent of the present invention are blended with the propylene polymer, that is, the compositions of the present invention.Comparative Example 1-(1) shows an example in which only the hindered amine of the present invention was blended as a stabilizer, and phenol or its phosphite ester and the nucleating agent of the present invention were not blended,
Comparative Example 1-(2) shows an example in which a hindered amine other than the one of the present invention was blended as a stabilizer. Comparative example 1-(3)~(
5) shows an example in which the phenol compound or its phosphoric acid ester according to the present invention was blended with a zoropyrene polymer having a Q value of 5 or more, but the hindered amine according to the present invention was not blended.

From the results in Table 1, it can be seen that the impact strength of the injection molded device of the present invention does not significantly decrease due to γ-ray irradiation, whereas the comparative example shows a significant decrease in impact strength.

Further, while the molded product of the present invention is not colored at all, the molded product of the comparative example is colored yellow. Furthermore, it has been shown to be excellent in terms of toxicity and suppressive effect on molecular weight reduction.

Example 2 In the same manner as in Example 1, pellets having the respective compositions listed in Table 2 were produced. However, the extruder is 50m long.

diameter (230°C) was used. The obtained pellets were applied to a Sumitomo Heavy Industries Necool 350T injection molding machine to form a syringe outer cylinder having an internal capacity of 1 oml (280°C), and irradiated with gamma rays in the same manner as in Example 1. The evaluation items were the first in Example 1.
In addition to those listed in the table, transparency was also evaluated visually. For the compression test, the syringe outer cylinder was placed in an oven at 80°C and heat-treated for a predetermined number of days. Using an autograph tester, a round bar with a radius of 5 mm was pressed against the center of the syringe outer cylinder at a speed of 50 mm 1 m 1 nm, and the syringe diameter ( Outer diameter 17
ii) Cracks were observed when the sample was deformed to about half its size.

If even one of the three samples was cracked, it was determined to be a crack. Regarding odor, use a syringe outer cylinder of 20μ, t?
After placing it in an IJ ester film and sealing it, it was irradiated with gamma rays, and 30 days after irradiation, it was opened, and a sensory test using the human sense of smell was conducted to determine the presence or absence of odor. Furthermore, as a method for evaluating the surface condition of the syringe, γ-ray irradiation 30
After several days, measure the contact angle between the syringe surface and the silicone droplet (
Polydimethylsiloxane (3000C8t) was used as a guideline for bleeding to the surface of decomposed products. The results are shown in Table 2.

37- Table 2 Evaluation of molded product of 325-inch outer cylinder for inner capacity 10me series 38- In Table 2, Example 2-C1) and (2) are as follows.
Propylene-ethylene random copolymer (Q value 5 or less)
Comparative Example 2 (1) to (5) is a test example of a molded article of a composition containing the stabilizer and nucleating agent of the present invention, that is, a molded article of the present invention. A test example is shown below in which a nucleating agent is added. From the results in Table 2, the molded products of the present invention have excellent performance in all evaluation items including degree of coloration, transparency, compressive strength, oven life, bleedability, odor, contact angle of silicone droplets, and toxicity. This shows that it can be put to practical use as a radiation-resistant medical device.

Changes in the contact angle of the silicone droplets in the above test indicate bleed of the additive onto the molded article surface. Example 2
In Comparative Example 2-(2), the contact angle did not increase significantly before and after radiation irradiation, but in Comparative Example 2-(1), it increased significantly. This indicates that in the case of the EC-1 compound, hydrophilic substances bled onto the surface and repelled silicone.

Example 3 Pellets prepared by melting and kneading powders having the respective compositions shown in Table 3 were molded into pellets with an outer diameter of 17.7 mm and a length of 7 mm using an injection molding machine.
It was molded into a syringe barrel having a cylindrical portion with a diameter of 50 mm and a wall thickness of 0.98 mm. The samples were wrapped in 20 micron polyethylene terephthalate packaging and irradiated with 25 megarads using a Cobalt 60 source. The samples are unirradiated group and 8 unirradiated ones.
The samples were divided into four groups: a group that was left in a 0°C air circulation oven for 7 days, a group that was left at room temperature for 30 days after irradiation, and a group that was left in an 80°C air circulation oven for 7 days after irradiation, and measurements were performed according to the following method. Ta.

The hue was determined visually, and no coloration was expressed as ◎, very slight yellowing as ◯, slight yellowing as △, and yellowing as ×.

For the potassium permanganate reducing substance, a sample cut into 1 square centimeter pieces was mixed with 10 times the volume of distilled water for 12 hours.
Extraction was carried out at 1° C. for 20 minutes, and the measurement was performed according to the disposable syringe standard section, and the result was expressed as ΔKMn O4.

Bleeding was determined visually. Those with no bleeding were indicated as -, and those where bleeding was observed = 39- were indicated as +.

The compressive strength was determined by compressing the center of the syringe with a 7 mm steel round bar and measuring the load at which the syringe broke. The measurement is 25
I went at ℃. In the table, the symbol - indicates no breakage.

For the impact strength, a cylinder with a weight of 1201 mm and a diameter of 30 mm was dropped at different heights, and the 50% fracture energy was determined according to JIS-7211. The measurement was carried out at 25°C. The crack generation time after irradiation was measured using a gear oven at 120°C, and the presence or absence of cracks was visually observed. Regarding the odor, when the package was opened, odorless products were indicated by ◎, products with a slight odor were indicated by ○, products with a strong odor were indicated by △, and products with an unpleasant odor were indicated by ×. Regarding transparency, haze was measured in accordance with ASTM (D-1003) for a sheet formed into a 1-thickness sheet. Cytotoxicity and hemolytic toxicity were tested using the same test method as in Example 1. The results are shown in Table 3.

-" -326 40- Table 3 -42- In Table 3, Example 3-(1) to (3) has a Q value of 4.
Comparative Example 3-(2) and (4) A test example of a molded article of a composition in which the stabilizer and nucleating agent of the present invention were blended with the propylene polymer of No. 4, that is, a molded article of the present invention. Comparative example 3-
(1) and (3) are examples in which the stabilizer of the present invention was blended, but the nucleating agent was not blended.

From the results in Table 3, the molded article of the present invention showed good results in all evaluation items, especially regarding elution of potassium permanganate reducing substances (ΔKMno4(rX)) and odor generation. It shows that the inventive nucleating agent is much better than the control one.

(1) Effects of the Invention According to the present invention, a propylene polymer medical device that can be commercially subjected to radiation sterilization is provided.

That is, according to the present invention, firstly, a medical instrument is provided in which the strength and transparency of the material are less reduced by radiation irradiation. Propylene polymer material deteriorates significantly when irradiated with radiation, but as shown above, molded products containing the stabilizer and nucleating agent of the present invention have less drop in impact strength, compressive strength, etc., and are transparent. It also retains its properties, making it suitable for practical use as a medical device.

According to the present invention, secondly, a medical instrument is provided that does not show coloration due to radiation irradiation. Some of the conventionally known stabilizers decompose when irradiated with radiation and cause the product to become colored, and such stabilizers should not be used in medical devices even if they have excellent anti-deterioration effects. I can't.

Thirdly, according to the present invention, a safe medical device is provided without bleeding of additives or elution of toxic decomposition products. Some conventional stabilizers bleed onto the product surface over time or decompose due to radiation irradiation to produce toxic substances, which elute into the contents that come into contact with medical devices. However, as shown above, such a phenomenon is not observed in the stabilizer used in the present invention.

Fourthly, according to the present invention, a medical instrument is provided that does not generate odor due to radiation irradiation. Zoropyrene polymer products contain a nucleating agent as a clarifying agent, but some of the nucleating agents conventionally used decompose when exposed to radiation and emit unpleasant odors. The nucleating agent used in the present invention is unlikely to generate any unpleasant odor.

As described above, the present invention has achieved a practical radiation sterilizable medical product by skillfully selecting and blending a specific stabilizer and nucleating agent with a zolopyrene polymer having a specific molecular weight distribution. It provides equipment.

Patent applicant: Terumo Corporation 45-

Claims (9)

[Claims] (1) 100 parts by weight of a propylene polymer having a ratio of weight average molecular weight to number average molecular weight of 5 or less is added as a stabilizer using the following formula CD-! or hindered amine 0.
01 to 0.4 parts by weight and the following formula [■]. 0.01 to 0.4 parts by weight of phenol or its phosphite compound represented by [■] or [■], and 0.01 to 0.01 to 0.4 parts by weight of a compound represented by the following formula [■] as a nucleating agent.
A medical device capable of radiation sterilization, characterized in that it is a molded article made of a composition containing 0.4 parts by weight. [■] -1-01" 2- In the above formula, R1 is an alkyl group having 1 to 12 carbon atoms, R2 is an alkyl group having 3 to 12 carbon atoms, 1Y is a divalent carbonized group having 1 to 18 carbon atoms, a hydrogen group or a sulfur atom, 2 is a divalent hydrocarbon group having 1 to 8 carbon atoms which may contain a carbonyloxy group, R5 and R6 are an alkyl or alkoxy group having 1 to 8 carbon atoms, a hydroxyl group, or Rodan atom, k is 1~
t is an integer of 1 to 16; m is an integer of 1 to 6; n and R2 are each independently an integer of 1 to 3; and p represents O or 1. (2) The ratio of weight average molecular weight to number average molecular weight is 2.5 to 4
8, 0.03 to 0.3 parts by weight of a hindered amine represented by the above formula [I] or (If) as a stabilizer, and the above formula ([0, [
IV] or [■] 0.02 to 0.2 parts by weight of a phenol or sulfurous acid ester compound, and a compound represented by the above formula (Vl) as a nucleating agent 10
．． The medical device according to claim 1, which is a molded article made of a composition containing 0.05 to 0.3 parts by weight. (3) The medical device according to claim 1 or 2, wherein the hindered amine is a compound in which R1 is a methyl group and k is 3 or 4 in the formula [I]. (4) In the formula [■], the hindered amine is
The medical device according to claim 1 or 2, wherein R1 is a methyl group and t is a compound represented by 2. (5) Claim 1, wherein the phenol compound is a compound represented by the formula [■], where R2 is a t-butyl group, R6 is a methyl group, X is a hydrogen atom, and m is 1.
The medical device described in any one of Items 1 to 4. (6) In the above formula [■], R2 is a t-butyl group (5th position), R is a methyl group (2nd position), and X is a group -P(OC48H37)2, m
The medical device according to any one of claims 1 to 4, wherein is a compound represented by 1. (7) The phenol phosphite compound is the formula [■], R2 is a t-butyl group (5th position), R3 is a methyl group (2nd position), X is a group -P(OC48H37)2,
The medical device according to any one of claims 1 to 4, wherein Y is a compound represented by the group >CH-CH2-CH2-CH3. (8) The phenol compound is R in formula [■]
The medical device according to any one of claims 1 to 4, wherein 2 and R6 are t-butyl groups (3, 5 positions), and z is a methylene group. (9) The nucleating agent according to any one of claims 1 to 8, wherein in the formula [■], R5 is a methyl group (4th position) and n is 1. Medical equipment. (10) The medical device according to any one of claims 1 to 9, wherein the molded product is an injection molded product. The medical device according to claim 10, which is an infusion or blood transfusion set, or a blood collection device. Hindered amine 0 represented by the following formula [I] or [ll]
．． 01 to 04 parts by weight, and the following formula [■]. [IV] 0.01 to 0.4 parts by weight of a phenol or its phosphite compound represented by t or [V] and 0.01 part of a compound represented by the following formula 1 [] as a nucleating agent.
A radiation sterilizable medical device, characterized in that it is a radiation sterilized molded article made of a composition containing ~0.4 parts by weight. [1) 7- In the above formula, R1 is an alkyl group having 1 to 12 carbon atoms, R2 is an alkyl group having 3 to 12 carbon atoms, or an alkyl group having 1 to 30 children), Y is the number of carbon atoms 1 to 18 divalent hydrocarbon group or sulfur atom, 2 is a divalent hydrocarbon group having 1 to 8 carbon atoms that may contain a carbonyloxy group, R5 and R6 are the number of carbon atoms 1 to 8 alkyl or alkoxy groups, hydroxyl groups, or helogne atoms, k is an integer of 1 to 10, t is an integer of 1 to 16, m is an integer of 1 to 6, n and R2 are each independently 1 to 3 and p represent O''! or 1, respectively. The medical instrument according to claim 12, wherein the radiation sterilization is γ-ray or X-ray sterilization.