JPH02200270A - Composition for medical implement - Google Patents

Abstract

PURPOSE:To enhance the mechanical strength, physiological safety, and safety to heat, light and radiations of a molding and to enable the radiation sterilization of the molding by incorporating a compd. selected from a group consisting of the polyesters formed by using unsatd. aliphat. dicarboxylic anhydride at 0.1 to 200 pts.wt. ratio. CONSTITUTION:This compsn. contains the compd. selected from the group consisting of the carboxylate formed by using unsatd. aliphat. alcohol, the polyester formed by using the unsatd. aliphat. dicarboxylic acid expressed by the formula (I) and the polyester formed by using the unsatd. aliphat. dicarboxylic anhydride expressed by the formula (II) at 0.1 to 200 pts.wt. ratio per 100 pts.wt. vinyl chloride resin. The adequate utilization of this compsn. by molding the same to medical implements, such as blood bags, transfusion sets, blood circuits and catheter and packaging materials for the medical implements, drugs, etc., is possible in this way.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a composition for medical devices, and more specifically, it has excellent mechanical strength and physiological safety for carvings, and is resistant to heat, light, and radiation. Excellent stability,
Radiation sterilization of molded objects is possible, such as medical instruments and instruments such as blood bags, infusion sets, blood circuits, catheters, etc.

The present invention relates to a composition for medical devices that can be suitably used by forming into packaging materials for drugs and the like.

[Prior art and the invention aims to solve the problem 1. Chloride, which has excellent processability, physiological safety and transparency, and is inexpensive, is used as a material for forming medical devices such as blood bags, infusion sets, and blood circuits. Vinyl resin is widely used.

Specifically, for example, 30 to 80 parts of di-2-ethylhexyl phthalate is added to 100 parts by weight of polyvinyl chloride.
parts by weight, 0.01 to 5 parts by weight of a calcium-zinc stabilizer, 0 to 10 parts by weight of epoxidized soybean oil as a stabilizing aid, and 0 to 5 parts by weight of other lubricants as necessary. Medical soft vinyl chloride resin compositions are known.

On the other hand, sterilization is essential for medical tools.

Methods for this sterilization treatment include a heat sterilization method, a sterilization method using a sterilizing agent, and a radiation sterilization method.

Among these various sterilization methods, the heat sterilization method has the disadvantage of requiring the resin to have high heat resistance and small thermal deformation, and the sterilization method using a sterilizing agent such as ethylene oxide, for example, While radiation sterilization has the disadvantage of requiring a long time to handle, it is widely used as an excellent sterilization method because it can be easily sterilized at low temperatures and does not require a long time to handle after sterilization. It has been adopted.

However, since vinyl chloride resin lacks stability against heat, light, and radiation, for example, when a molded article made using the medical soft vinyl chloride resin composition is sterilized by radiation sterilization, it easily deteriorates due to radiation. That is, there is a problem that coloration, molecular cleavage, cross-linking, etc. occur, making it impossible to put it into practical use.

Therefore, various attempts have been made to improve the stability of vinyl chloride resins against heat, light and radiation.

For example, it has been shown that adding organic compounds of heavy metals such as lead and cadmium to vinyl chloride resin improves its stability against heat, light, and radiation; however, these organic compounds of heavy metals are not toxic. Since it is strong and harmful to the human body, it cannot be incorporated into compositions for medical devices.

Therefore, in medical vinyl chloride resin compositions,
Generally, metal soap stabilizers such as calcium and zinc, which are considered non-toxic, are added. However, medical vinyl chloride resin compositions containing metal soap stabilizers do not yet have sufficient stability against heat, light, and radiation.

Therefore, in order to solve this problem, for example, the general formula (A
); R* OCOCR3miCR,C0ORo (A) [However, Rt and R3 are alkyl groups having 1 to 15 carbon atoms, and R3 and R4 are.

General formula (B); -C, Hs-* (B) (where n
is 0-6. ). ] 0.1 to 50 parts by weight of an unsaturated aliphatic dicarboxylic acid dialkyl ester represented by
A gamma ray sterilizable medical device containing 0 parts by weight has been proposed (see Japanese Patent Application Laid-Open No. 61-2864).

However, although this medical device has improved stability in the short term immediately after radiation sterilization, it still becomes colored and loses transparency over time, so it cannot be used for a long period of time, such as several months. Not suitable for blood bags that may be stored.

That is, a composition for medical devices that has sufficient stability against heat, light and radiation, and can be made into a molded article that does not change over a long period of time even after radiation sterilization treatment. The current situation is that things are desired.

The present invention has been made based on the above circumstances.

An object of the present invention is to provide molded products with excellent mechanical strength and physiological safety, as well as excellent stability against heat, light, and radiation, and to enable radiation sterilization of molded products, such as blood bags and infusion sets. It is an object of the present invention to provide a composition for medical devices that can be suitably used for medical devices such as blood circuits, catheters, and packaging materials for medical devices.

[Means for Solving the Problems] In order to solve the above problems, the present inventor has made extensive studies and found that a vinyl chloride resin composition containing at least a vinyl chloride resin and a specific compound in a specific ratio is In addition to having excellent mechanical strength and physiological safety, it also has excellent stability against heat, light, and radiation, making it possible to sterilize molded products by radiation, such as blood bags and infusion sets.

The present invention was achieved by discovering that the present invention can be suitably used for blood circuits, medical instruments such as catheters, packaging materials for medical instruments, and the like.

The structure of the present invention is based on 100 parts by weight of vinyl chloride resin.
Carboxylic acid ester using an unsaturated aliphatic alcohol, the following formula (I); [In formula (1), n is an integer of 2 to 14. ] A polyester using an unsaturated aliphatic dicarboxylic acid represented by the following formula (■); [However, in formula 1 (■), n has the same meaning as above. ] A compound selected from the group consisting of polyester using an unsaturated aliphatic dicarboxylic anhydride represented by
This is a composition for medical devices, characterized in that the composition contains 0.1 to 200 parts by weight.

The composition for medical devices of the present invention comprises a vinyl chloride resin and a carboxylic acid ester using an unsaturated aliphatic alcohol;
A compound selected from the group consisting of a polyester using an unsaturated aliphatic dicarboxylic acid represented by the above formula (I), and a polyester using an unsaturated aliphatic dicarboxylic acid anhydride represented by the above formula (II) Contains.

Examples of the vinyl chloride resin include vinyl chloride homopolymers, vinyl chloride copolymers, and polyvinylidene chloride.

Preferred examples of the vinyl chloride copolymer include:

40% by weight or more, preferably 65% by weight or more, more preferably 75% by weight or more of vinyl chloride monomer.

Examples include copolymers of the vinyl chloride monomer and other monomers that can be copolymerized.

Examples of the other monomers include donyl acetate, vinylidene chloride, ethylene, propylene, vinyl bromide, vinyl fluoride, styrene, vinyltoluene, vinylpyridine,
Acrylic acid, methacrylic acid, acrylonitrile, methacrylonitosol: Alkyl acrylates such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate: methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, etc. and alkyl methacrylates.

In the present invention, a styrene-acrylonitrile copolymer and/or a styrene-methacrylonitrile copolymer can also be blended with the vinyl chloride resin. In this case, the blending ratio of the vinyl chloride resin and the styrene-acrylonitrile copolymer and/or the styrene-methacrylonitrile copolymer is based on 100 parts by weight of the vinyl chloride resin. The total amount of styrene-methacrylonitrile copolymer is usually 5 to 80 parts by weight, preferably lθ to
201 & quantity parts. When styrene-acrylonitrile copolymer and/or styrene-methacrylonitrile copolymer in the above proportion is blended with the vinyl chloride resin,
Hardness, heat deformation temperature, etc. can be improved.

The average degree of polymerization of the vinyl chloride resin is 1, usually 400 to 3.
,000, preferably 600 to 2,700, more preferably 800 to 1,700. If the average degree of polymerization of the vinyl chloride resin is less than 400, it may easily deteriorate and may not have sufficient mechanical strength.

On the other hand, if it exceeds 3,000, moldability may deteriorate.

One of the important points in the present invention is that, together with the vinyl chloride resin, a carboxylic acid ester using an unsaturated aliphatic alcohol, a polyester using an unsaturated aliphatic dicarboxylic acid represented by the formula (I), and the above formula (
tl) containing a compound selected from the group consisting of polyesters using unsaturated aliphatic dicarboxylic acid anhydrides.

In the present invention, surprisingly, a carboxylic acid ester using an unsaturated aliphatic alcohol, the formula (I)
A compound selected from the group consisting of a polyester using an unsaturated aliphatic dicarboxylic acid represented by the above formula (II) and a polyester using an unsaturated aliphatic dicarboxylic acid anhydride represented by the above formula (II) is added to the vinyl chloride compound. By containing 0.1 to 200 parts by weight per 100 parts by weight of the resin, the stability against heat, light and radiation is unexpectedly improved, and especially the stability against radiation is significantly improved.

It is generally known that vinyl chloride resin forms a conjugated polyene structure when exposed to heat, light or radiation. This decomposition reaction causes so-called radiation deterioration such as coloring and molecular cleavage, but if alcohol residues and carboxylic acid residues that constitute the above-mentioned specific compounds are present during this decomposition reaction, The carbon atoms at the α and δ positions and the unsaturated moieties of the alcohol residue and the carboxylic acid residue react, for example, as follows to produce a six-membered ring.

...CHmiCH... That is, the conjugated polyene structure is cleaved by the Diels-Alder reaction between the conjugated polyene, the alcohol residue, and the carboxylic acid residue, and the above-mentioned deterioration is stopped. It is assumed that.

Examples of the unsaturated aliphatic alcohol include allyl alcohol, crotyl alcohol, 2-buten-1-ol, and 3-buten-1-ol.

2-penten-1-ol, 3-hexen-1-ol, 2-hebuten-1-ol, 2-year-old cten-1-ol, 10-undecen-1-ol.

11-dodecen-1-ol, 12-tridecen-l-
All, oleyl alcohol, elaidyl alcohol,
Examples include lylyl alcohol and lylunyl alcohol.

Among these, unsaturated aliphatic alcohols whose alkenyl carbon number is in the range of 3 to 24 are preferred, and allyl alcohol and 2-octen-1-ol are particularly preferred.

The various unsaturated aliphatic alcohols mentioned above may be used alone or in combination of two or more.

As the carboxylic acid in the carboxylic acid ester,
For example, oxalic acid, malonic acid, succinic acid, glutaric acid,
Adipic acid, pimelic acid, speric acid, azelaic acid,
Aliphatic dicarboxylic acids such as sebacic acid: (anhydrous) maleic acid, fumaric acid, glutaconic acid, (anhydrous) citraconic acid,
Unsaturated aliphatic dicarboxylic acids such as mesaconic acid, (anhydrous) dimethylmaleic acid, (anhydrous) itaconic acid, and dimethylfumaric acid = (anhydrous) phthalic acid, isophthalic acid.

Examples include aromatic carboxylic acids such as (anhydrous) trimellitic acid, trimesic acid, (anhydrous) pyromellitic acid, galloyl gallic acid, and benzenehexacarboxylic acid.

Among these, preferred are phthalic anhydride, adipic acid, trimellitic anhydride and maleic acid.

These may be used alone or in combination of two or more.

Examples of the unsaturated aliphatic dicarboxylic acid represented by the formula (1) include maleic acid, fumaric acid, glutaconic acid, itaconic acid, citraconic acid, mesaconic acid, dimethylmaleic acid, and dimethylfumaric acid.

Examples of the unsaturated aliphatic dicarboxylic acid anhydride represented by the formula (II) include maleic anhydride, itaconic anhydride, citraconic anhydride, and dimethylmaleic anhydride.

The unsaturated aliphatic dicarboxylic acid represented by the above formula (I) and the unsaturated aliphatic dicarboxylic acid anhydride represented by the above formula (■) may be used alone or in combination of two or more. Good too.

Among the unsaturated aliphatic dicarboxylic acids represented by the formula (I) and the unsaturated aliphatic dicarboxylic anhydrides represented by the formula (■), maleic acid and maleic anhydride are preferred, and particularly preferred are maleic acid and maleic anhydride. Maleic anhydride.

A polyester formed using an unsaturated aliphatic dicarboxylic acid represented by the above formula (I) or a polyester formed using an unsaturated aliphatic dicarboxylic acid anhydride fatty acid represented by the above formula (II) is represented by the above formula (1). It can be obtained by suitably using, for example, an aliphatic alcohol together with the unsaturated aliphatic dicarboxylic acid represented by the formula (II) or the unsaturated aliphatic dicarboxylic acid anhydride fatty acid represented by the formula (II).

Examples of the aliphatic alcohol include aliphatic diols.

Specifically, for example, ethylene glycol, propylene glycol (including diols in which the alkyl group has 1 to 4 carbon atoms in 2,2-dialkyl-1,3-propanediol), butanediol, bentanediol,
Examples include hexanediol.

These may be used alone or in combination of two or more.

In the present invention, for example, oxalic acid, malonic acid, succinic acid, The polyester is prepared using aliphatic dicarboxylic acids such as glutaric acid, adipic acid, pimelic acid, superric acid, azelaic acid, and sebacic acid; aromatic dicarboxylic acids such as (anhydrous) phthalic acid, isophthalic acid, and terephthalic acid. You can also do that.

When using the aliphatic dicarboxylic acids and aromatic dicarboxylic acids, these may be used alone or in combination of two or more.

Further, as a reaction terminator for obtaining the polyester, for example, hexanol, heptatool, n
- Aliphatic alcohols such as octatool, 2-ethylhexanol, myristyl alcohol, cetyl alcohol, stearyl alcohol, l-docosanol; hexanoic acid, heptanoic acid, n-octylic acid, 2-ethylhexanoic acid, lauric acid, myristic acid, Fatty acids such as valmitic acid, stearic acid, arachidic acid, and behenic acid can be used.

Among these, preferred are aliphatic alcohols and fatty acids having about 6 to 16 carbon atoms.

The average molecular weight of the polyester using the unsaturated aliphatic dicarboxylic acid represented by the formula (I) and the polyester using the unsaturated aliphatic dicarboxylic acid anhydride fatty acid represented by the formula (n) is 1, usually 600. Above, preferably 1,000 to 3,000. If the average molecular weight is less than 600, stability against heat, light and radiation may not be sufficient. On the other hand, if it exceeds 3,000, the viscosity may be too high and workability may deteriorate.

In the present invention, the vinyl chloride resin, the carboxylic acid ester using an unsaturated aliphatic alcohol, the polyester using the unsaturated aliphatic dicarboxylic acid represented by the above formula (I), and the above formula (n) The blending ratio of the specific compound with a compound selected from the group consisting of polyesters made of unsaturated aliphatic dicarboxylic acid anhydrides and fatty acids represented by: 100 parts by weight of the vinyl chloride 4# fat is Usually, it is 0.1 to 200 parts by weight, preferably 10 to 100 parts by weight. If the blending ratio of the specific compound to 100 parts by weight of the vinyl chloride resin is less than 0.1 parts by weight, stability against heat, light and radiation may not be sufficient.

The medical device composition of the present invention may contain other plasticizers together with the vinyl chloride resin and the specific compound in order to improve plasticity and cold resistance.

As the plasticizer having such an effect, any of those generally used for vinyl chloride resins can be suitably used. Specifically, di-2-ethylhexyl phthalate (DOP), butylbenzyl phthalate (BBP), dilauryl phthalate (DLP),
dibutyl phthalate (11) IP), dibutyl phthalate (DIP), di-n-octyl phthalate (DnO
P), diisooctyl phthalate (DIOP), didecyl phthalate (DDP), diisodecyl phthalate (
DIDP), 7-talic acid esters such as octyldecyl phthalate; dioctyl adipate (DOA), diisodecyl adipate (DIllA), dialkyl adipate (D610A), dibutyl diglycol adibate)
Adipic acid esters such as (BXA); dibutyl sebacate (DBS), dioctyl sebacate (DO3)
, diisooctyl sebakey) (DIO3), butylbenzyl sebakey)-(BBS); sebacic acid esters such as dioctyl azelate (00K), dioctyl azelate (DH2), diisooctyl azelate (
Azelaic acid esters such as DIOZ); Citric acid esters such as triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate, tri-2-ethylhexyl acetyl citrate: methyl phthalyl ethyl glycolate (IIPEG) , ethyl phthalyl ethyl glycolate (EPEG), butyl phthalyl butyl glycolate (BP[IG), and other glycolic acid esters; tributyl trimellitate (TBT
II), trimellitic acid esters such as trihexyl trimellitate (NHT), tri-n-octyl trimellitate (TnOT), and triisooctyl trimellitate (TIθ Dingmen): tetrabutylpyromellitate (T
BPII), tetraoctylpyromellitate (Topm
) Pyromellitic acid esters such as nitricresyl phosphate (TCP), phosphoric acid (trisisopropylphenyl), tributyl phosphate (TBP), )
ethyl phosphate (TEP), )-lioctyl phosphate)-(TOP), tri(chloroethyl) phosphate (TCEP), triphenyl phosphate (
TPP), tricylenyl phosphate (τXP)
), phosphoric acid esters such as monooctyl diphenyl phosphate, and 1,000 butyl dixylenyl phosphate; epoxidized animal and vegetable oils such as epoxidized soybean oil and epoxidized linseed oil; and epoxy plasticizers such as octyl epoxide late. It will be done.

Among these, phthalic acid dialkyl esters are preferred, and phthalic acid dialkyl esters in which each alkyl group has 6 to 13 carbon atoms can be particularly preferably used.

When the plasticizer is used, the blending ratio of the vinyl chloride resin and the plasticizer is such that the plasticizer is usually 200 parts by weight or less, preferably 5 to 50 parts by weight, per 100 parts by weight of the vinyl chloride resin. It is. Said vinyl chloride resin 10
Even if the blending ratio of the plasticizer to 0 parts by weight exceeds 200 parts by weight, the corresponding effect will not be achieved, and on the contrary, problems such as a decrease in adhesive strength may occur.

In the present invention, in addition to the vinyl chloride resin and the compound, and the optionally used plasticizer, for example, calcium stearate, calcium laurate, calcium ricinoleate, calcium naphthenate, zinc stearate, zinc laurate, etc. , metal soaps such as zinc ricinoleate and zinc naphthenate; lubricants such as calcium stearate, butyl stearate, stearyl alcohol, bisamide, 2,4.6-tri-tert-butylphenol, 4.4"-iso-propylene Phenolic antioxidants such as redene bisphenol; Amine antioxidants such as dilaurylthiodipropionate and distearylthiopropionate; Phosphate such as triphenyl phosphite, diphenyldecyl phosphite, and phenylisodecyl phosphite. It may contain other components such as a system antioxidant. When containing these other components, the blending ratio of the vinyl chloride resin and other components is as follows:
Based on 100 parts by weight of the vinyl chloride resin.

Other components are usually 10 parts by weight or less, preferably 0.5 parts by weight.
~5 parts by weight. Even if the blending ratio of the functional component to 100 parts by weight of the vinyl chloride resin exceeds 10 parts by weight, the corresponding effect may not be achieved.

The composition for medical devices of the present invention usually contains each of the above-mentioned components,
For example, it is kneaded using a Pan Bali mixer, a mixing roll, etc., and then it is shaped into a sheet by a calender roll method.
Primary molding is performed into a film, and it can be used as is or with secondary molding as appropriate to produce blood bags, infusion sets, etc.
It can be suitably used for medical devices such as blood circuits and catheters, as well as packaging materials for medical devices, drugs, etc. Also, for example, by injection molding, medical devices such as blood bags, infusion sets, blood circuits, catheters, etc. It can also be molded into shapes.

For sterilization of these medical tools, radiation sterilization using electromagnetic radiation such as gamma rays and electron beams can be suitably employed, and in particular, radiation sterilization using gamma rays can be suitably employed.

For example, when radiation sterilization using gamma rays is employed, the irradiation intensity of gamma rays is usually 1 to 5 rad, preferably 1.5 to 311 rad. This irradiation intensity is I M
If it is less than rad, the sterilization effect may not be sufficient. On the other hand, if it exceeds 5111 rad, so-called radiation deterioration such as coloring, molecular cleavage, and crosslinking may occur in molded articles made using the composition for medical devices of the present invention.

[Example] Next, the present invention will be described in more detail by showing examples and comparative examples of the present invention.

(Example 1) To 100 parts by weight of polyvinyl chloride with an average degree of polymerization of 1,030, 60 parts by weight of diallyl maleate (AP), 4 parts by weight of epoxy soybean oil and 1 part by weight of a Ca-Zn stabilizer were mixed using a mixing roll. Knead it, then make it about 1m thick.
A press sheet of m was molded.

This sheet was irradiated with gamma rays of % 3 rad and 511 rad to examine changes in the coloring state over time.

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet.

The results are shown in Table 2.

The test methods and conditions for the tensile test and migration test are as follows.

Tensile test: JIS 6723 Migration test: Loading 40 g/cm” AS resin plate
70℃, 168 hours PS resin board 70℃, 168 hours ABS resin board 70℃, 168 hours Acrylic l111It board 70℃, humidity 80%, 24
01fll (Example 2) In the above Example 1, diallyl phthalate (DAP)
Example 1 was carried out in the same manner as in Example 1, except that diallyl adipate (DAA) was used instead of diallyl adipate (DAA).

The results are shown in Table #I1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Example 3) In Example 1, diallyl phthalate (DAP)
The same procedure as in Example 1 was carried out except that triallyl trimellitate (TATal) was used instead of .

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Example 4) In Example 1, diallyl phthalate (DAP)
Example 1 was carried out in the same manner as in Example 1, except that diallyl malate (DAM) was used instead of diallyl malate (DAM).

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Example 5) In Example 1, diallyl phthalate (DAP)
Example 1 was carried out in the same manner as in Example 1, except that dioleylmale (DOIII) was used instead of dioleylmale (DOIII).

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Comparative Example 1) In Example 1, diallyl phthalate (DAP)
Instead of di-2-ethylhexyl phthalate (DOP
) was used, except that a press sheet was formed in the same manner as in Example 1, and the press sheet was irradiated with γ-rays of 311 Irad and 511 rad to examine changes in the coloring state over time.

The results are shown in Table 1.

Further, this sheet was subjected to a tensile test and a migration test in the same manner as in Example 1 marked with #.

The results are shown in Table 2.

(Comparative Example 2) In Example 1, diallyl phthalate (DAP)
Instead of di-2-ethylhexyl fumarate (DOF
) was used, except that a press sheet was formed in the same manner as in Example 1, and the press sheet was irradiated with γ-rays of 3 Mrad and 5 Mrad to examine changes in the colored state over time.

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Example 6) In the above Example 1, diallyl phthalate (AP)
Instead of adipic acid/maleic anhydride (adipic acid/
Maleic anhydride-9/l), 1,3-butanediol/
1,4-butanediol (l,3-butanediol/1
．． The same procedure as in Example 1 was carried out except that a polyester plasticizer having an average molecular weight of 1,800 and consisting of 4-butanediol (1/1) and 2-ethylhexanol was used.

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 92.

(Example 7) In the above Example 1, diallyl phthalate (DAP)
In place of S water maleic acid, 1,3-butanediol/
l, 4-butanediol (1,3-butanediol/l
, 4-butanediol=1/1) and 2-ethylhexanol] and a polyester plasticizer having an average molecular weight of 800.

It was carried out in the same manner as in Example 1 above.

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(Comparative Example 3) In Example 6, adipic acid/maleic anhydride (
Adipic acid/maleic anhydride; 9/1), 1.3
-butanediol/l, 4-butanediol (1,3-
Average molecular weight t, a consisting of butanediol/l, 4-butane oligool=1/1) and 2-ethylhexanol
In place of the polyester plasticizer in oo, adipic acid, 1
．． 3-butanediol/l, 4-butanediol (1,
3-butanediol/l, 4-butanediol-1/1
) and 2-ethylhexanol with an average molecular weight of 1
, 800 polyester plasticizer was used, a press sheet was formed in the same manner as in Example 1, and this press sheet was irradiated with γ-rays of 3 Mrad and 5 Mrad to observe the change in coloring state over time. I looked into it.

The results are shown in Table 1.

Further, a tensile test and a migration test were conducted on this sheet in the same manner as in Example 1 above.

The results are shown in Table 2.

(This page, blank spaces below) (Evaluation) As is clear from Table 1, a sheet made using the composition for medical devices of the present invention can be heated for 6 months at room temperature after being irradiated with, for example, 5 Mrad of radiation. It does not change color or lose transparency even if it is left unused, and does not cause any radiation deterioration. It was confirmed that the stability against radiation was significantly improved compared to the sheets made using the conventional compositions for medical devices in Comparative Examples 1 to 3.

Furthermore, as is clear from Table 2, the sheet made using the composition for medical devices of the present invention has significantly improved stability against radiation compared to the sheet made using the conventional composition for medical devices. Despite this, it was confirmed that the tensile strength, elongation, migration properties, etc. were equal to or higher than those of conventional compositions for medical devices.

〔Effect of the invention] According to the invention.

(1) Dramatically improves the stability of vinyl chloride resin against heat, light, and radiation compared to vinyl chloride resin, which has excellent processability, physiological safety, and transparency, and is low in price. 0.1~
Since it is contained in an amount of 200 parts by weight, the molded product has excellent mechanical strength and physiological safety, and is extremely stable against heat, light and radiation, and can be used for DT die-carving radiation sterilization.

(2) Even if the molded product is sterilized by radiation sterilization,
It does not cause so-called radiation deterioration such as coloring, molecular cutting, or cross-linking over a long period of time.

(3) Industrially useful medical devices that have the following advantages, such as being suitable for use in medical devices such as blood bags, infusion sets, blood circuits, catheters, and packaging materials for medical devices, drugs, etc. A composition can be provided.

Claims (1)

[Claims] (1) Carboxylic acid ester prepared by using unsaturated aliphatic alcohol with respect to 100 parts by weight of vinyl chloride resin, the following formula (
I); ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) [However, in formula (I), n is an integer from 2 to 14.
] A polyester made using an unsaturated aliphatic dicarboxylic acid represented by the following formula (II): ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) [However, in formula (II), n is the same as above It is the meaning. ] A compound selected from the group consisting of polyester using an unsaturated aliphatic dicarboxylic anhydride represented by
A composition for medical devices, characterized in that the composition contains 0.1 to 200 parts by weight.