JPH0242506B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a medical hard resin composition and a medical device. Specifically, the present invention relates to medical hard resin compositions and medical devices that have extremely high safety and do not cause hemolysis when they come into contact with blood. (Prior art) Currently, hard resin compositions are often used in place of glass, metal, etc. for various hard medical devices because they are lightweight, hard to break, inexpensive, and disposable. It is being By the way, it is very important for such medical devices to be inert to blood components. However, for example, if blood is collected into a conventionally used blood collection tube made of glass or hard resin and then stored in the blood collection tube for a long time, red blood cells become hemolyzed. Hemoglobin released due to hemolysis adversely affects various measurement results for clinical tests. Generally, a blood bag containing donated blood is attached with a blood collection tube containing the same blood as the blood in the blood bag to check compatibility with the patient's blood before transfusion. However, near the 21st day (in Japan), which is the expiration date of the red blood cell concentrate, the blood in the blood collection tube becomes hemolyzed, which interferes with the test. This was a problem. Therefore, it is desired to develop a hard resin that does not cause hemolysis even when it comes into contact with blood for a long time. (Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a novel medical hard resin composition and a medical device.
Another object of the present invention is to provide a medical hard resin composition and a medical device that have excellent preservability for red blood cells. A further object of the present invention is to provide a medical hard resin composition and a medical device with high physiological safety. (Means for Solving the Problems) The above objectives are to provide a hard resin composition with the general formula () RCOOR' () (where R and R' are each a chain hydrocarbon group having 3 or more carbon atoms. and the sum of the carbon numbers of R and R' is 11 to 30. The present invention provides a medical hard resin composition containing 0.5 to 5% by weight of a monocarboxylic acid ester represented by the above general formula ().
The present invention also provides R in the general formula () or
This indicates a medical hard resin composition in which at least one of R' has a branched structure. The present invention also provides a medical hard resin composition in which at least one of R or R' in the general formula () has a branched structure. The present invention further provides a medical hard resin composition in which the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate or 2-ethylhexyl-2-ethylhexanoate. It is.
The present invention also provides a medical hard resin composition in which the hard resin is selected from the group consisting of hard vinyl chloride resin, acrylic resin, styrene resin, olefin resin, thermoplastic polyester resin, and polycarbonate. It shows. The present invention further provides a medical hard resin composition in which the acrylic resin is a homopolymer or copolymer of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile, or methacrylonitrile. The present invention also provides a medical hard resin composition in which the styrenic resin is polystyrene, an acrylonitrile-styrene copolymer, or an acrylonitrile-butadiene-styrene copolymer. The present invention also provides a medical hard resin composition in which the olefinic resin is polyethylene, polypropylene, or an ethylene-propylene copolymer. The present invention also provides a medical hard resin composition in which the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate. The above objects further achieve the following by adding a compound having the general formula () RCOOR' () (wherein R and R' are each a chain hydrocarbon group having 3 or more carbon atoms, and R and R' This is achieved by a medical device that is substantially composed of a hard resin composition containing a monocarboxylic acid ester having the sum of carbon atoms of 11 to 30. The present invention also provides a medical device characterized in that it is substantially composed of a hard resin composition containing 0.5 to 5% by weight of a monocarboxylic acid ester represented by the general formula (). The present invention also provides a medical device in which at least one of R or R' in the general formula () has a branched structure. The present invention further provides a medical device in which the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate or 2-ethylhexyl-2-ethylhexanoate. The present invention also provides a medical device in which the hard resin is selected from the group consisting of hard vinyl chloride resins, acrylic resins, styrenic resins, olefin resins, thermoplastic polyester resins, and polycarbonates. .
The invention further provides a medical device in which the acrylic resin is a homopolymer or copolymer of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile or methacrylonitrile. The present invention also provides a medical device in which the styrenic resin is polystyrene, acrylonitrile-styrene copolymer, or acrylonitrile-butadiene-styrene copolymer. The present invention also provides a medical device in which the olefinic resin is polyethylene, polypropylene or ethylene-propylene copolymer. The present invention also provides a medical device in which the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate. The present invention further provides a medical device characterized in that it is a blood collection tube. (Function) Therefore, the medical hard resin composition of the present invention:
In the hard resin composition, the general formula () RCOOR' () (wherein R and R' are each a chain carbon hydrogen group having 3 or more carbon atoms, and the sum of the carbon numbers of R and R' is The biggest feature is that it contains a monocarboxylic acid ester represented by 11 to 30). Surprisingly, this monocarboxylic acid ester compound represented by the general formula () has the same effect on preventing red blood cell hemolysis as di-2-ethylhexyl phthalate, and on the other hand, unlike di-2-ethylhexyl phthalate, it has an effect on platelets. It was found that no adverse effects on blood components, such as an effect of suppressing aggregation ability, were observed. Furthermore, the monocarboxylic acid ester compound represented by the general formula () has sufficient compatibility with various hard resins, so if it is blended with the monocarboxylic acid ester compound represented by the general formula (), it can be used in contact with blood. When this is done, it is possible to obtain a hard resin composition with good preservability for red blood cells. That is, when the hard resin composition comes into contact with blood, the action of the monocarboxylic acid ester compound represented by the general formula () that elutes and migrates from the resin composition prevents hemolysis of red blood cells, resulting in a protective effect on red blood cells. It will be of excellent quality. Therefore, the medical hard resin composition of the present invention is suitable as a medical material, and molded products made using the material have excellent safety, processability, transparency, Because it has heat resistance, it can be very effective when used as a medical device, and its effect is particularly remarkable in the case of medical devices that come into contact with body fluids such as blood, such as blood collection tubes. Hereinafter, the present invention will be explained in more detail based on embodiments. The hard resin used in the medical hard resin composition according to the present invention must be physiologically safe and have appropriate compatibility with the monocarboxylic acid ester compound represented by the general formula () as described below. It is not particularly limited as long as it has, and examples thereof include hard vinyl chloride resins, acrylic resins, styrene resins, olefin resins, thermoplastic polyester resins, and polycarbonates. In addition, for these hard resins, regardless of the type of hard resin, the melt flow index is 0.5 to 30 g/10 min, especially 5 to 12 g/10 min.
It is preferable that the condition is within a certain range. As the hard vinyl chloride resin, in addition to vinyl chloride homopolymers, other copolymerizable resins containing vinyl chloride at 40% by weight or more, preferably 65% by weight or more, most preferably 75% by weight or more, such as: Examples include copolymers with monomers such as vinylidene chloride, ethylene, propylene, styrene, methyl methacrylate, and acrylonitrile. Examples of acrylic resins include alkyl (meth)acrylates such as methyl methacrylate, methyl acrylate, ethyl methacrylate, and ethyl acrylate, acrylonitrile,
There are homopolymers and copolymers such as methacrylonitrile. Examples of polystyrene resin include polystyrene, acrylonitrile-styrene copolymer,
Examples include acrylonitrile-butadiene-styrene copolymer (ABS resin). Examples of the olefin resin include medium to high density polyethylene, polypropylene, and copolymers of combinations of ethylene, propylene, and other α-olefins, such as ethylene-propylene copolymers. Examples of thermoplastic polyester resins include polyethylene terephthalate and polybutylene terephthalate. Furthermore, as polycarbonate, in addition to bisphenol A type polycarbonate,
It includes those having various carbonate type structures. It should be noted that the hard resin used in the medical hard resin composition of the present invention is of course not limited to those exemplified above, but further includes various resin polymer blends. It is something that can be done. Therefore, in the medical hard composition of the present invention,
General formula () RCOOR' () (However, in the formula, R and R' each have 3 or more carbon atoms,
It is preferably a chain carbon hydrogen group of 3 to 22, most preferably 3 to 18, and the sum of the carbon numbers of R and R' is
11-30, preferably 11-21. ) is blended with a monocarboxylic acid ester. The monocarboxylic acid ester represented by the general formula () acts as a hemolysis inhibitor in the medical hard resin composition of the present invention. That is, when blood comes into contact with a product made of the medical hard resin composition of the present invention, the monocarboxylic acid ester represented by the general formula () eluted from the composition exerts a protective effect on red blood cells. It is something. In the monocarboxylic acid ester represented by the general formula (), the number of carbon atoms in R and R' is 3 or more because if the chain is a chain hydrocarbon chain with less than 3 carbon atoms, the compound may become toxic. This is because it is not appropriate to incorporate it into a medical hard resin composition. Furthermore, in the monocarboxylic acid ester represented by the general formula (), R and
The reason why the sum of the carbon numbers with R′ is 11 to 30 is that if the sum of the carbon numbers is less than 11, it will not have the effect of preventing hemolysis, whereas if the sum of the carbon numbers exceeds 30, it will not work with vinyl chloride resin. This is because compatibility is lost and uniform dispersion in the resin composition becomes difficult. Further, in the monocarboxylic acid ester represented by the general formula (), it is more preferable that at least one of the chain hydrocarbon groups R and R' has a branched structure in order to improve the compatibility with the hard resin and the effect of preventing hemolysis. Furthermore, the chain hydrocarbon groups R and R' may be saturated or unsaturated chain hydrocarbon groups. Specifically, the monocarboxylic acid ester represented by the general formula () includes 2-ethylhexylbutyrate, 2-ethylhexylisobutyrate,
Isoheptyl valerate, 2-ethylhexyl valerate, isoheptyl pivalate, 2-ethylhexyl pivalate, isopentylhexanoate, isohexylhexanoate, 2-ethylhexylhexanoate, isobutyl-2-ethylhexanoate, Isopentyl-2-ethylhexanoate, 2-ethylhexyl-2-ethylhexanoate, isopropyldecanoate, isobutyldecanoate, 2-ethylhexyldecanoate, isopropyl laurate, isobutyl laurate, 2-ethylhexyl laurate , 2-
Ethylhexyl isolaurate, isopropyl myristate, isobutyl myristate, 2-ethylhexyl myristate, isopropyl palmitate, isobutyl palmitate, 2-ethylhexyl palmitate, isopropyl stearate,
Examples include, but are not limited to, isobutyl stearate, 2-ethylhexyl stearate, isopropyl isostearate, isobutyl isostearate, 2-ethylhexyl isostearate, isopropyl oleate, isobutyl oleate, 2-ethylhexyl oleate, etc. It's not like that. Preferred among these compounds are isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate, and 2-ethylhexyl 2-ethylhexanoate, most preferably 2-ethylhexyl 2-ethylhexanoate. be. The monocarboxylic acid ester represented by the above general formula () is blended in the medical hard resin composition of the present invention in an amount of 0.5 to 5% by weight, more preferably 2 to 3% by weight. That is, the general formula ()
The amount of monocarboxylic acid ester expressed as
This is because if the amount is less than 0.5% by weight, the effect of suppressing hemolysis of red blood cells will not be sufficient, while if it exceeds 5% by weight, the physical properties of the hard resin composition may be deteriorated. Furthermore, additives such as various stabilizers, lubricants, and antioxidants may be added to the medical hard resin composition of the present invention, if necessary. The medical hard resin composition of the present invention can be molded by any of the methods used for conventional hard resin compositions, such as injection molding and extrusion molding. The medical device of the present invention contains the general formula () RCOOR' () (wherein R and R' are each a chain carbon hydrogen group having 3 or more carbon atoms, and R and R' The composition is substantially composed of a hard resin composition containing a monocarboxylic acid ester represented by It has various physical properties such as heat resistance, and is particularly effective in suppressing hemolysis of red blood cells. Therefore, the medical devices of the present invention preferably include those that come into contact with body fluids such as blood, concentrated red blood cells, or body fluid component solutions, such as blood collection tubes, and particularly those that come in contact for a long time. Preferred examples include, but are not limited to, various artificial organs such as blood collection bottles, test tubes, scissors, artificial lungs, artificial kidneys, etc., and housings for heat exchangers, etc. . Next, one embodiment of the medical device according to the present invention will be described with reference to the drawings, taking a blood collection tube as an example. That is, FIG. 1 shows a tubular member 2 made of the medical hard resin composition according to the present invention with one end closed and the other end open, and a punctureable butyl rubber member with the open end 3 of the tubular member 2 sealed. 1 shows a reduced pressure blood collection tube 1 which maintains an internal space 5 formed by a stopper member 4 in a reduced pressure state. The reduced pressure blood collection tube 1 having such a configuration is used in the following manner. That is, as shown in FIG. 2, one end is closed and the other end is open, and a blood collection needle 7 is screwed into the screw hole 6 of the closed end 10. Blood vessel holder 8
The reduced pressure blood collection tube 1 is inserted into the tube from the open end 3 side. This blood collection needle 7 consists of a blood vessel piercing part 7a and a plug puncturing part 7b, and a synthetic resin luer adapter 9.
It is packaged in Next, when the blood vessel piercing part 7a of the blood collection needle 7 is inserted under pressure into the closed end 10 of the blood collection tube holder 8, the plug puncture part 7b of the blood collection needle 7 punctures the luer adapter 9 and the plug member 4, as shown in FIG. Since the blood reaches the internal space 5 of the blood collection tube 1, the blood vessel and the internal space 5 communicate with each other, and due to the negative pressure in the internal space 5, the blood in the blood vessel reaches the internal space 5 of the blood collection tube 1 only by the degree of vacuum. flow inside. Next, blood collection is completed by removing the blood vessel piercing portion 7b of the blood collection needle 7 from the blood vessel, and the collected blood is stored in the blood collection tube 1 until it is subjected to a test. However, as described above, the blood collection tube 1 is made of the medical hard resin composition of the present invention, and the monocarboxylic acid ester compound represented by the general formula () elutes and transfers from the composition into the blood. Since the hemolysis of red blood cells is suppressed by the action of , free hemoglobin does not have a negative effect on various measurements for clinical tests, and accurate test values can be obtained even if the storage period is long. Become. The above explanation uses blood collection tubes as an example, but other blood collection bottles, test tubes, shears, oxygenators,
Housings for various artificial organs such as artificial kidneys and heat exchangers are also suitably constructed from the above-mentioned hard resin composition. (Examples) Hereinafter, the present invention will be explained in more detail based on Examples. Example 1 Polyethylene terephthalate (UNIPET)
A pellet containing 100 parts by weight of RT560 (manufactured by Nippon Unipet Co., Ltd.) and 3 parts by weight of isopropyl isolaurate was prepared using a vented twin-screw extruder, and the pellet was injection molded into a 5 ml pellet. A blood collection tube was prepared. Approximately 3 ml of human EDTA-added blood was dispensed into the blood collection tube and stored at 4°C for 3 weeks.
After that, the plasma hemoglobin concentration was measured using the TMB method (Clinical Chemistry 23 749-(1977) [Clin.
Chem. 23 749-(1977)]. Results first
Shown in the table. Examples 2-3 Same as Example 1 except that 2-ethylhexyl isostearate (Example 2) or 2-ethylhexyl-2-ethylhexanoate (Example 3) is used in place of isopropyl isolaurate. A blood collection tube was prepared, and similar experiments were conducted using this blood collection tube. The results are shown in Table 1. Comparative Example 1 For comparison, a blood collection tube was prepared in the same manner as in Example 1 using pellets made only of polyethylene terephthalate (Unipet RT560, manufactured by Nippon Unipet Co., Ltd.), and the same experiment was conducted on this blood collection tube. Summer. The results are shown in Table 1. Example 4 Polystyrene (Estyrene G-12F, manufactured by Nippon Steel Chemical Co., Ltd.) was used instead of polyethylene terephthalate.
A blood collection tube was prepared in the same manner as in Example 1, except that a sample was used, and the same experiment was conducted on this blood collection tube. The results are shown in Table 1. Examples 5-6 Same as Example 4 except that 2-ethylhexyl isostearate (Example 5) or 2-ethylhexyl-2-ethylhexanoate (Example 6) is used in place of isopropyl isolaurate. A blood collection tube was prepared, and similar experiments were conducted using this blood collection tube. The results are shown in Table 1. Comparative Example 2 For comparison, polystyrene (Estyrene G
-12F, manufactured by Nippon Steel Chemical Co., Ltd.), a blood collection tube was prepared in the same manner as in Example 1,
A similar experiment was conducted using this blood collection tube. The results are shown in Table 1. Example 7 A blood collection tube was prepared in the same manner as in Example 1, except that polymethyl methacrylate (Parapet G, manufactured by Kyowa Gas Chemical Industry Co., Ltd.) was used instead of polyethylene thyrephthalate, and the same experiment was performed on this blood collection tube. I did this. The results are shown in Table 1. Examples 8-9 Same as Example 7 except that 2-ethylhexyl isostearate (Example 8) or 2-ethylhexyl-2-ethylhexanoate (Example 9) is used in place of isopropyl isolaurate. A blood collection tube was prepared, and similar experiments were conducted using this blood collection tube. The results are shown in Table 1. Comparative Example 3 For comparison, a blood collection tube was prepared in the same manner as in Example 1 using pellets made only of polymethyl methacrylate (Parapet G, manufactured by Kyowa Gas Chemical Industry Co., Ltd.). I conducted an experiment. The results are shown in Table 1. Example 10 Example 1 except that polyacrylonitrile (BAREX210, manufactured by Vestron Corp.) was used instead of polyethylene terephthalate.
A blood collection tube was prepared in the same manner as described above, and the same experiment was conducted using this blood collection tube. The results are shown in Table 1. Examples 11-12 Same as Example 10 except that 2-ethylhexyl isostearate (Example 11) or 2-ethylhexyl-2-ethylhexanoate (Example 12) is used in place of isopropyl isolaurate. A blood collection tube was prepared, and similar experiments were conducted using this blood collection tube. The results are shown in Table 1. Comparative Example 4 For comparison, polyacrylonitrile (BAREX210, Vestron
A blood collection tube was prepared in the same manner as in Example 1 using pellets made only by J.D. Co., Ltd.), and the same experiment was conducted on this blood collection tube. The results are shown in Table 1.

[Table] Sosteare
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Comparative example 4 Polyacrylic − 120
Lonitrile
*Each plasma hemoglobin concentration value is expressed as the average of three data values.
As is clear from the results shown in Table 1, when the hard resin composition according to the present invention was used (Examples 1 to
12), the elution was suppressed to a low level compared to the case of using a hard resin composition that does not contain the monocarboxylic acid ester compound according to the present invention and hardly elutes anything into the blood (Comparative Examples 1 to 4). I found out that (Effects of the Invention) As described above, the present invention provides a hard resin composition containing a compound having the general formula () RCOOR' () (where R and R' are each a chain hydrocarbon group having 3 or more carbon atoms. and the sum of the carbon numbers of R and R' is 11 to 30. Unlike hard resin compositions, it has the effect of suppressing hemolysis of red blood cells, and has physical properties such as moldability, transparency, and heat resistance that are comparable to conventional hard resin compositions. It can be molded by any molding method, such as injection molding or extrusion molding, and is ideal as a material for medical devices, especially medical devices that come into contact with blood, such as blood collection tubes. . Furthermore, when 0.5 to 5% by weight of a monocarboxylic acid ester represented by the general formula () is blended in the medical hard resin composition of the present invention, at least one of R or R' in the general formula () has a branched structure. It is something. More preferably, the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate,
2-ethylhexyl isostearate or 2-
In the case of ethylhexyl-2-ethylhexanoate, in addition, the hard resin is selected from the group consisting of hard vinyl chloride resin, acrylic resin, styrene resin, olefin resin, thermoplastic polyester resin, and polycarbonate. , furthermore, the acrylic resin is a homopolymer or copolymer of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile, or methacrylonitrile, and the styrene resin is polystyrene, an acrylonitrile-styrene copolymer, or acrylonitrile-butadiene. - When the olefin resin is polyethylene, polypropylene or ethylene-propylene copolymer, and the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate, safety, hemolysis inhibitory effect and Other physical properties become even better. The present invention also provides a rigid resin composition having the general formula () RCOOR' () (wherein R and R' are each a chain hydrocarbon group having 3 or more carbon atoms, and The medical device is substantially composed of a hard resin composition containing a monocarboxylic acid ester represented by It is an excellent medical device that exhibits a hemolysis-inhibiting effect on red blood cells, and that there is no risk of denaturing blood components, especially when medical devices can come into contact with blood, such as blood collection tubes. Even when used as a blood collection tube, there is no need to worry about free hemoglobin interfering with various tests due to hemolysis even after storing blood for a long time. Furthermore, in the medical device of the present invention, when the hard resin composition substantially constituting the medical device contains 0.5 to 5% by weight of a monocarboxylic acid ester represented by the general formula (), and R in the general formula () or R′ has a branched structure, and more preferably the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate or 2-ethylhexyl-2- In the case of ethylhexanoate, in addition, the hard resin is selected from the group consisting of hard vinyl chloride resin, acrylic resin, styrene resin, olefin resin, thermoplastic polyester resin, and polycarbonate, and acrylic resin. The resin is a homopolymer or copolymer of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile, or methacrylonitrile, and the styrene resin is polystyrene, acrylonitrile-styrene copolymer, or acrylonitrile-butadiene-styrene copolymer. When the olefinic resin is polyethylene, polypropylene or ethylene-propylene copolymer, and the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate, safety, hemolysis inhibiting action, and heat resistance, It would be a better medical device in other respects, such as transparency.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the medical device of the present invention, and FIGS. 2 and 3 are cross-sectional views showing how the same embodiment is used. DESCRIPTION OF SYMBOLS 1... Decompression blood collection tube, 2... Tubular member, 4... Plug member, 5... Internal space, 6... Screw hole, 7... Blood collection needle, 8... Blood collection tube holder, 9... Luer adapter.

Claims (1)

[Scope of Claims] 1. In the hard resin composition, the general formula () RCOOR' () (wherein R and R' are each a chain hydrocarbon group having 3 or more carbon atoms, and R and R' A hard resin composition for medical use, characterized in that it contains a monocarboxylic acid ester having the sum of carbon numbers of 11 to 30. 2. The medical hard resin composition according to claim 1, which contains 0.5 to 5% by weight of a monocarboxylic acid ester represented by the general formula (). 3. The medical hard resin composition according to claim 1 or 2, wherein at least one of R or R' in the general formula () has a branched structure. 4 Claims 1 to 3, wherein the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate, or 2-ethylhexyl-2-ethylhexanoate. The medical hard resin composition according to any one of the above. 5 The hard resin is hard vinyl chloride resin, acrylic resin, styrene resin, olefin resin,
The medical hard resin composition according to any one of claims 1 to 4, which is selected from the group consisting of thermoplastic polyester resins and polycarbonates. 6 The acrylic resin is methyl methacrylate,
The medical hard resin composition according to claim 5, which is a homopolymer or copolymer of methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile, or methacrylonitrile. 7. The medical hard resin composition according to claim 5, wherein the styrene resin is polystyrene, an acrylonitrile-styrene copolymer, or an acrylonitrile-butadiene-styrene copolymer. 8. The medical hard resin composition according to claim 5, wherein the olefin resin is polyethylene, polypropylene, or an ethylene-propylene copolymer. 9. The medical hard resin composition according to claim 5, wherein the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate. 10 In the hard resin composition, a compound of the general formula () RCOOR' () (wherein R and R' are each a chain hydrocarbon group having 3 or more carbon atoms, and is 11 to 30.) A medical device characterized in that it is substantially composed of a hard resin composition containing a monocarboxylic acid ester represented by the following. 11. The medical treatment according to claim 10, which is substantially composed of a hard resin composition containing 0.5 to 5% by weight of a monocarboxylic acid ester represented by the general formula (). Tools. 12. The medical device according to claim 10 or 11, wherein at least one of R or R' in the general formula () has a branched structure. 13. Claims 10 to 12, wherein the compound represented by the general formula () is isopropyl isolaurate, isopropyl oleate, 2-ethylhexyl isostearate or 2-ethylhexyl-2-ethylhexanoate. Medical equipment described in any of the above. 14. Claims 10 to 13, wherein the hard resin is selected from the group consisting of hard vinyl chloride resin, acrylic resin, styrene resin, olefin resin, thermoplastic polyester resin, and polycarbonate. Medical equipment described in any of the paragraphs. 15. The medical device according to claim 14, wherein the acrylic resin is a homopolymer or copolymer of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, acrylonitrile, or methacrylonitrile. 16. The medical device according to claim 14, wherein the styrene resin is polystyrene, an acrylonitrile-styrene copolymer, or an acrylonitrile-butadiene-styrene copolymer. 17. The medical device according to claim 14, wherein the olefin resin is polyethylene, polypropylene, or an ethylene-propylene copolymer. 18. The medical device according to claim 14, wherein the thermoplastic polyester resin is polyethylene terephthalate or polybutylene terephthalate. 19. The medical device according to any one of claims 10 to 18, which is a blood collection tube.