JP2010193957A - Composite material, medical tube and medical catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the friction characteristics on the surface of a composite material with a particulate material blended/kneaded into a base matrix in the composite material and a medical tube. <P>SOLUTION: The medical tube 1 is composed of the base matrix 2A including at least one kind of thermoplastic resin; and composite particles 2B compounded at least on the surface of the base matrix 2A. The composite particles 2B include mother particles 2a, whose average circularity is at least 0.90 and whose average particle diameter is at least 0.1 μm and not more than 30 μm, and child particles 2b attached to the surface of the mother particles 2a, whose average particle diameter is not more than one tenth that of the mother particles 2a. The composite particles 2B are formed of the composite material 2 to which 15-75 pts.wt. of the base matrix 2A relative to 100 pts.wt. of the composite material are added. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composite material, a medical tube, and a medical catheter.

Conventionally, a medical tube is used as, for example, a treatment instrument tube (sheath) or a medical catheter that is inserted into a treatment portion in the body through a channel tube of an endoscope. Such a medical tube is required to reduce the amount of insertion force by, for example, reducing sliding resistance with respect to a channel tube or blood vessel of an endoscope.
For example, Patent Document 1 discloses a composite material including a polymer matrix consisting essentially of one or more thermoplastic polyesters and a finely divided lubricating granular material, and a catheter in which an insertion tube member is formed in the body by the composite material. Are listed.
In Patent Document 1, for example, a finely pulverized lubricating granular material made of graphite, molybdenum disulfide, or the like is mixed with a polymer matrix made of thermoplastic polyester, thereby reducing the coefficient of friction of the material and improving the insertion property of the treatment instrument tube. ing.

Japanese National Patent Publication No. 10-503103

However, the conventional composite materials and medical tubes as described above have the following problems.
In the technique described in Patent Document 1, by mixing finely pulverized lubricating granular materials, a composite material having a lower friction than that of a polymer matrix can be obtained. However, the particle shape is not controlled, so the reduction in friction is limited. is there. And according to patent document 1, the friction coefficient of this composite material is about 0.03 to about 0.20, and has a big dispersion | variation.
As described above, when the friction coefficient varies and the friction coefficient increases, there is a problem that the amount of insertion force when the medical tube is inserted varies and increases.
Medical tubes need to be quickly inserted into the body, and even after insertion, the insertion position must be finely adjusted by the operator's operation according to the treatment position. ing.

  The present invention has been made in view of the above problems, and is a composite material, medical tube, and medical catheter capable of improving the frictional properties of the surface of a composite material in which a particle material is combined with a polymer material. The purpose is to provide.

In order to solve the above problems, the composite material of the present invention is a composite material comprising a polymer material containing one or more types of thermoplastic resins and a particle material composited on at least the surface of the polymer material. The particle material has an average circularity of 0.90 or more and an average particle diameter of 0.1 μm or more and 30 μm or less, and an average particle diameter of 1/10 or less of the mother particles, A composite particle including child particles attached to the surface of the mother particle, and the composite particle is added in an amount of 15 parts by weight to 75 parts by weight with respect to 100 parts by weight of the polymer material. .
According to this invention, the composite particles constituting the particle material are composed of mother particles having an average circularity of 0.90 or more and child particles having an average particle diameter of 1/10 or less of the mother particles. The particle shape as a composite particle becomes close to a sphere while the particles and the child particles have good bonding strength. For this reason, since the child particles are dispersedly arranged on the mother particles close to the sphere, the contact area with respect to the other member on the surface of the composite particles becomes small, and the surface friction coefficient becomes low. In addition, since the composite particle is a projection close to a sphere on the surface of the polymer material, when the other member contacts along the surface of the polymer material, the contact becomes smoother than the square projection, Protrusions with low resistance. Therefore, the surface friction coefficient of the composite material can be reduced.
If the average circularity of the mother particles is less than 0.90, the shape of the mother particles is too different from the sphere, so when other members come in contact with the surface of the polymer material, it becomes a convex portion with a large resistance, The surface friction coefficient of the composite material becomes large.
Also, if the average particle size of the child particles is larger than one-tenth of the mother particles, it is difficult to bond the mother particles and the child particles, and even if they are bonded, the bond strength decreases, so the child particles are peeled off. And the surface of the mother particle cannot be covered with the child particles. For this reason, the contact area of the surface of the composite particle becomes too large, and the surface friction coefficient of the composite particle cannot be suitably reduced.
Further, if the average particle diameter of the mother particles is less than 0.1 μm, sufficient bond strength with the child particles cannot be maintained, and separation occurs during molding. In addition, if the average particle diameter of the base particles is larger than 30 μm, the size of the unevenness and the pitch of the unevenness of the surface of the polymer material are increased, which is the same as when the surface is roughened, and the surface friction coefficient is suitably reduced. Can not do it.
Further, if the amount of the composite particles added is less than 15 parts by weight, the number of composite particles present in the polymer material becomes too small, so that the number of composite particles exposed on the surface of the polymer material becomes too small. The surface friction coefficient cannot be reduced suitably.
In addition, when the amount of the composite particles added is more than 75 parts by weight, the composite particles are aggregated with each other. It cannot be reduced.

  The circularity e referred to in this specification is measured using a flow type particle image analyzer (manufactured by Sysmex Corporation) and is defined as follows.

e = (circumference of a circle having the same area as that of the particle projection image) / (perimeter of the particle projection image)
... (1)

According to this flow type particle image analyzer, an enlarged image of a particle is acquired, and image processing is performed to obtain the area and circumference of the particle, and the circularity is calculated based on the above equation (1). .
For example, the circularity of a perfect circle is 1. In the example of a regular polygon, the regular hexagon is 0.952, the regular pentagon is 0.930, the square is 0.886, and the regular triangle is 0.777.

In the composite material of the present invention, the child particles preferably have a graphite structure or a molybdenum sulfide structure.
In this case, since the child particles have a graphite-type structure or a molybdenum sulfide-type structure, the child particles become a layered substance, so that the child particles on the surface of the composite material are easily sheared by an external force. Thereby, the slip property of the surface of a composite material can be improved.

In the composite material of the present invention, the child particles include aluminum oxide (Al ₂ O ₃ ), barium sulfate (BaSO ₄ ), tungsten oxide (WO ₃ ), tungsten (W), bismuth oxide (BiO ₃ ), and It is preferable to include one or more of silicon carbide (SiC).
In this case, since Al ₂ O ₃ , BaSO ₄ , WO ₃ , W, BiO ₃ , and SiC are chemically stable, when the composite particles are subjected to external force, at the interface between the polymer material and the composite particles. The surface friction coefficient can be reduced by generating shear slip in the polymer material.

The medical tube of the present invention has a configuration using the composite material of the present invention.
According to this invention, since the composite material of the present invention is used, the same action as that of the composite material of the present invention is provided.

The medical catheter of the present invention is configured using the medical tube of the present invention.
According to this invention, since the medical tube of the present invention is used, the same action as that of the medical tube of the present invention is provided.

  According to the composite material, the medical tube and the medical catheter of the present invention, the composite material obtained by combining the mother particles having good circularity and the child particles having an average particle diameter of 1/10 or less of the mother particles is a polymer material. Therefore, it is possible to improve the frictional properties of the surface of the composite material in which the particle material is combined with the polymer material.

It is typical sectional drawing which follows the axial direction which shows schematic structure of the medical tube which concerns on the 1st Embodiment of this invention. It is a typical partial expanded sectional view of the A section of FIG. It is a photographic image of the surface in an example of the composite material which concerns on the 1st Embodiment of this invention. It is a schematic explanatory drawing explaining the measuring apparatus and measuring method which were used for the surface friction coefficient measurement of a composite material. It is a schematic explanatory drawing explaining the measuring apparatus and measuring method of the amount of insertion force of a medical tube. It is a bar graph which shows the measurement result of the surface friction coefficient of each Example and each comparative example, and insertion force amount.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
First, the composite material and medical tube (medical catheter) according to the first embodiment of the present invention will be described.
FIG. 1 is a schematic cross-sectional view along the axial direction showing a schematic configuration of the medical tube according to the first embodiment of the present invention. FIG. 2 is a schematic partial enlarged cross-sectional view of a portion A in FIG. FIG. 3 is a photographic image of the surface of an example of the composite material according to the first embodiment of the present invention. 1 and 2 are schematic diagrams, and the dimensional ratio, number, and shape are exaggerated (the same applies to the following drawings).

As shown in FIG. 1, the medical tube 1 of the present embodiment is a flexible tube in which a tube body is formed in a cylindrical shape having an inner diameter d ₁ , an outer diameter d ₂ , and a length L. It can be used for a catheter or the like that is inserted into a channel tube of an endoscope and assists in the treatment of the affected area or the extraction of the affected area. As the inner diameter d ₁ , the outer diameter d ₂ , and the length L, for example, dimensions such as d ₁ = 1.7 (mm), d ₂ = 2.4 (mm), and L = 2000 (mm) may be adopted. it can.
As shown in FIG. 2, the tube main body of the medical tube 1 has a composite matrix 2B kneaded in a base matrix (polymer material) 2A made of a polymer material containing one or more thermoplastic resins. The composite material 2 is formed into the above tube shape.
The compounding ratio of the composite particles 2B in the composite material 2 is 15 to 75 parts by weight with respect to 100 parts by weight of the base matrix 2A.

The material of the base matrix 2A is not particularly limited as long as it is a polymer material containing one or more kinds of thermoplastic resins. For example, the following examples can be given.
Polyethylene (PE) resin, ionomer resin (for example, ethylene-methacrylic acid copolymer ionomer resin), polypropylene (PP) resin, ultrahigh molecular weight PP, polybutene, 4-methylpentene-1 polymer, cyclic polyolefin resin, styrene resin ( For example, polystyrene, butadiene-styrene resin, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene (ABS) resin, etc.), polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyacetal, polyphenylene oxide, polyvinyl acetate, polyvinyl alcohol, polymethacryl Methyl acid (PMMA), cellulose acetate, polyester resin (for example, polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate) Etc.), polyamide (PA) resin, polyimide resin, fluororesin, polysulfone, polyethersulfone, polyarylate, polyetheretherketone, liquid crystal polymer, thermoplastic polyurethane, thermoplastic elastomer, biodegradable polymer, A polymer etc. are mentioned.
Here, the PE resin may be any of low density PE, high density PE, linear low density PE, and ultra high molecular weight PE. Moreover, as PP resin, any of homo PP, random PP, and block PP may be sufficient, and any of an atactic structure and a syndiotactic structure may be sufficient.
As an example, the base matrix 2A of the present embodiment employs Pebax (registered trademark) 6333SN01 (manufactured by Arkema). This Pebax (registered trademark) 6333SN01 is a polyether block amide copolymer having a hard segment made of PA and a soft segment made of polyether, and is a thermoplastic PA elastomer having high flexibility and rebound resilience. .

The composite particle 2B has an average particle diameter of 0.90 or more and 1.0 or less, an average particle diameter of 0.1 μm or more and 30 μm or less, and an average particle diameter of 1/10 or less of the mother particle 2a. It consists of a plurality of child particles 2b attached to the surface of the mother particle 2a. That is, as shown in FIG. 2, the diameter of the mother particle 2a _{d a,} if the diameter of the daughter particles 2b and _{d b,} respective mean values _{d Aave,} between _{d Bave is, d bave} ≦ 0.1 · There is a d _ave relationship.
Moreover, the average particle diameter of the composite particle 2B is approximately (d _ave + 2 · d _bave ).

  The material of the mother particle 2a is either an inorganic material, an organic material, or a hybrid thereof, and the material is not particularly limited. In this embodiment, PMMA particles (manufactured by Soken Chemical Co., Ltd.) are employed as an example.

As the material of the child particles 2b, appropriate inorganic particles having a layered structure can be adopted. Examples of such a layered structure include a graphite type structure and a molybdenum sulfide type structure, and it is preferable to include one or more kinds of inorganic particles having these layered structures.
Examples of the substance having a graphite type structure include graphite (C), boron nitride (BN), magnesium boride (MgB), magnesium diboride (MgB ₂ ), LiBC, HBC, C ₆ B _{2 and the} like. Can do.
Examples of the substance having a molybdenum sulfide type structure include tungsten disulfide (WS ₂ ), molybdenum disulfide (MoS ₂ ), niobium disulfide (NbS ₂ ), and tantalum disulfide (TaS ₂ ).
As a material of the child particles 2b of the present embodiment, MoS ₂ is adopted as an example.

  As a composite method for producing composite particles 2B from the mother particles 2a and the child particles 2b, for example, a mechanochemical method can be employed. In the present embodiment, they are combined using a hybridization system manufactured by Nara Machinery Co., Ltd.

According to the medical tube 1 having such a configuration, the composite material 2 obtained by kneading the composite particles 2B with a blending ratio of 15 parts by weight or more and 75 parts by weight or less with respect to 100 parts by weight of the base matrix 2A is formed. Therefore, the composite particles 2B are dispersed inside the medical tube 1, and a part of the composite particles 2B is exposed to the outer surface 1a as shown in FIG. Further, although not particularly illustrated, the composite particles 2B are exposed on the inner surface 1b as well. In the following description, the outer surface 1a and the inner surface 1b indicate surfaces including the composite particles 2B exposed on the surface of the base matrix 2A.
Accordingly, when the medical tube 1 is inserted into an endoscope channel tube or the like as a medical catheter, for example, or when a wire or the like is inserted into the medical tube 1, Since the composite particles 2B dispersed and exposed on the outer surface 1a and the inner surface 1b are in contact with each other and slip, the surface friction coefficient of the medical tube 1 can be reduced.
The composite particle 2B has a shape in which the base particle 2a has an average circularity of 0.90 or more and an average particle diameter of 0.1 μm or more and 30 μm or less, and the child particle 2b is 1/10 or less of the base particle 2a. Since the average particle diameter is attached to the surface of the mother particle 2a, a fine uneven state having a substantially spherical surface is formed on the outer surface 1a or the inner surface 1b. Therefore, smooth contact with the contact object is possible, and the surface friction coefficient as the medical tube 1 can be reduced.

Further, the surface of the composite particle 2B is covered with a small-diameter child particle 2b, and this child particle 2b includes MoS ₂ having a graphite-type structure which is a layered crystal structure. Shear slip occurs. Therefore, the frictional force at the contact portion can be reduced as compared with the case of only the mother particles 2a or the case where only the inorganic particles that do not cause shear slip are attached to the surface.

When the blending ratio of the composite particles 2B is less than 15 parts by weight, the blending amount is small, so that the composite particles 2B exposed on the outer surface 1a and the inner surface 1b become too small, and the friction coefficient on the outer surface 1a and the inner surface 1b It is almost determined by the friction coefficient of the 2A material. For this reason, the surface friction coefficient of the medical tube 1 cannot be reduced so much from the friction coefficient determined by the material of the base matrix 2A.
When the compounding ratio of the composite particles 2B exceeds 75 parts by weight, there are too many composite particles 2B in the composite material 2, and aggregation is likely to occur between the composite particles 2B, and the composite exposed to the outer surface 1a and the inner surface 1b. The apparent particle diameter of the particle 2B increases. For this reason, the unevenness | corrugation of the outer surface 1a and the inner surface 1b increases, and since the outer surface 1a and the inner surface 1b will be in the rough state, the surface friction coefficient as the medical tube 1 will become large.

When the average particle diameter of the mother particles 2a is less than 0.1 μm, the surface energy of the mother particles 2a becomes too large, so that the mother particles 2a tend to be aggregated, and the child particles 2b are formed on the surfaces of the individual mother particles 2a. It becomes difficult to attach.
Further, when the average particle diameter of the mother particle 2a exceeds 30 μm, the irregularities on the outer surface 1a and the inner surface 1b become large, and the outer surface 1a and the inner surface 1b become rough, so that the surface friction coefficient increases. End up.
Further, if the average circularity of the mother particle 2a is less than 0.90, too many sharp corners are formed on the surface of the mother particle 2a and thus the composite particle 2B. Since these sharp corners are exposed on the outer surface 1a and the inner surface 1b, the contact resistance is increased, so that the surface friction coefficient is increased.
Here, the average circularity is an evaluation scale of the degree of roundness of the particles, and means an average value of the circularity e calculated from the above formula (1).

  Thus, since the composite material 2 of this embodiment has improved surface friction characteristics, the surface friction coefficients of the outer surface 1a and the inner surface 1b of the medical tube 1 using the composite material 2 are reduced. Thus, when the medical tube 1 is inserted into the endoscope channel tube or a wire is inserted into the medical tube 1, it is possible to reduce the force at the time of insertion and insertion.

[Second Embodiment]
Next, a medical tube (medical catheter) according to a second embodiment of the present invention will be described.
The medical tube 11 of the present embodiment has the same shape as the medical tube 1 of the first embodiment, and the tube body is formed using the composite material 12 instead of the composite material 2. .
As shown in FIG. 2, the composite material 12 uses a child particle 12b having the same shape as that of the child particle 2b but different from the material in place of the child particle 2b of the first embodiment. Hereinafter, a description will be given centering on differences from the first embodiment.

The child particles 12b are inorganic particles containing any one of Al ₂ O ₃ , BaSO ₄ , WO ₃ , W, BiO ₃ , and SiC.

  According to such a configuration, since the child particles 12b are chemically stable, the binding force at the interface with the base matrix 2A is small, and the composite particles 12B exposed on the outer surface 1a and the inner surface 1b When an external force along the outer surface 1a and the inner surface 1b is applied, shear slip occurs in the base matrix 2A at the interface between the base matrix 2A and the child particles 12b. As a result, the friction characteristics of the outer surface 1a and the inner surface 1b of the medical tube 11 can be improved.

In the above description, the example in which the material of the child particle 2b (12b) is one type has been described. It may be combined. For example, (a) a plurality of types of inorganic particles having a graphite type structure or a molybdenum sulfide type structure, or (b) a plurality of types of Al ₂ O ₃ , BaSO ₄ , WO ₃ , W, BiO ₃ , SiC. You may mix, respectively, and you may make it compound so that one or more types of each inorganic particle of the material contained in said (a) and (b) may be included.
Further, the composite particles are not limited to one type, and the mother particles 2a of a plurality of different types of materials may be added so that the total amount is 15 parts by weight or more and 75 parts by weight or less.

  In addition, all the components described in the above embodiments can be implemented in appropriate combination within the scope of the technical idea of the present invention.

Below, the Example of each said embodiment is described with a comparative example.
FIG. 4 is a schematic explanatory view for explaining a measuring apparatus and a measuring method used for measuring the surface friction coefficient of the composite material. FIG. 5 is a schematic explanatory diagram for explaining a measuring device and a measuring method of the insertion force amount of the medical tube. FIG. 6 is a bar graph showing the measurement results of the surface friction coefficient and the insertion force amount of each example and each comparative example. The horizontal axis indicates the numbers of the example and the comparative example as actual 1, ratio 1, etc., respectively. The vertical axis represents the surface friction coefficient and the amount of insertion force (N).

[Examples 1 to 8 of the first embodiment]
Table 1 shows the configurations of the base matrix 2A and the composite particles 2B of the medical tubes 1 of Examples 1 to 8 of the first embodiment together with the configurations of the base matrix and inorganic particles of the medical tubes of Comparative Examples 1 to 7. Show.
The manufactured medical tubes have the same shape, and the inner diameter d ₁ , the outer diameter d ₂ , and the length L are d ₁ = 1.7 (mm) and d ₂ = 2.4 (mm), respectively. L = 2000 (mm) (common to the following examples and comparative examples).

As shown in Table 1, in Examples 1 to 8, all of the base matrix 2A were Pebax (registered trademark) 6333SN01 (manufactured by Arkema), and PMMA (Soken Chemical) was used as the base particle 2a of the composite particle 2B. (Made by Co., Ltd.) was adopted. In addition, as child particles 2b of the composite particle 2B, Examples 1 to 7 employ MoS ₂ (manufactured by Daizo Co., Ltd.), and Example 8 employs BN. The particle diameter ratio, which is the ratio of the average particle diameter of the child particles 2b to the average particle diameter of the mother particles 2a, was set to be mother particle: child particle = 10: 1.
And the child particle 2b was compounded on the surface of the mother particle 2a by a hybridization system manufactured by Nara Machinery Co., Ltd. (the following examples and comparative examples 2 to 7 are also the same).

In Examples 1 to 3, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 15 parts by weight, and the average circularity of the mother particles 2a was 0.90. However, the average particle diameter of the mother particle 2a was set to 0.10 μm, 20 μm, and 30 μm in Examples 1, 2, and 3, respectively.
In Examples 4 and 5, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 15 parts by weight, and the average particle diameter of the mother particles 2a was 30 μm. However, the average circularity of the mother particle 2a was 1.00 and 0.95, respectively.
In Examples 6 and 7, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 40 parts by weight and 75 parts by weight, respectively, and the average particle diameter and average circularity of the mother particles 2a were 30 μm, 0. 90.
In Example 8, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 15 parts by weight, and the average particle diameter and average circularity of the base particles 2a were 30 μm and 0.90, respectively. Example 8 is an example in which only the material of Example 3 and the child particles 2b is different.

  Here, the value measured by the particle size distribution analyzer SALD-7100 (manufactured by Shimadzu Corporation) was adopted as the average particle size. Moreover, the value measured using the flow type particle image analyzer (made by Sysmex Corporation) was employ | adopted for average circularity. The measurement method of the average particle diameter and the average circularity is common to the other examples and comparative examples.

In Comparative Example 1, the tube main body is formed using only the base matrix 2A.
In Comparative Examples 2 to 4, the compounding ratio of the composite particles 2B to 100 parts by weight of the base matrix 2A was 15 parts by weight in common. However, the average particle diameter of the mother particle 2a was 50 μm, 0.05 μm, and 30 μm in Comparative Examples 2, 3, and 4, respectively. The average circularity of the mother particle 2a was set to 0.90, 0.90, and 0.80 in Comparative Examples 2, 3, and 4, respectively.
In Comparative Example 5, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 5 parts by weight, and the average particle diameter and average circularity of the base particles 2a were 30 μm and 0.90, respectively.
In Comparative Example 6, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 90 parts by weight, and the average particle diameter and average circularity of the mother particles 2a were 30 μm and 0.90, respectively.
As described above, in Comparative Examples 2 to 6, the particle size ratio was set to be mother particle: child particle = 10: 1.
In Comparative Example 7, the compounding ratio of the composite particles 2B with respect to 100 parts by weight of the base matrix 2A was 15 parts by weight. The average particle diameter and average circularity of the mother particle 2a were 30 μm and 0.90, respectively, and the particle diameter ratio was mother particle: child particle = 5: 1.
That is, Comparative Example 1 does not include the composite particles 2B, Comparative Examples 2 and 3 are in terms of the average particle diameter of the base particles 2a, and Comparative Example 4 is in terms of the average circularity of the base particles 2a. In this respect, Comparative Examples 5 and 6 are examples of the compounding ratio of the composite particles 2B, and Comparative Example 7 is an example not included in the scope of the present invention in terms of the particle diameter ratio.

  Each of these Examples and Comparative Examples was evaluated by measuring the surface friction coefficient of the composite material and the amount of insertion force when inserting the tube body formed of each composite material into the bent tube. These measurement methods are the same in the following other examples and comparative examples.

As shown in FIG. 4, the surface friction coefficient is measured by a moving base 51 that reciprocates with the measurement sample fixed, a weight 52 for pressing the measurement counterpart member 52 with a constant load against the measurement sample, The measurement was performed using a friction coefficient measuring device 50 including a load converter 54 that measures a friction force from a measurement sample acting on the mating member 52. HEIDON (trade name; manufactured by Shinto Kagaku Co., Ltd.) was used as the friction coefficient measuring device 50 in this measurement.
In this measurement, the sample base 60 manufactured from the composite material 2 is fixed to the moving base 51, and the moving base 51 is driven to reciprocate while the measurement counterpart member 52 is pressed against the sample base 60 by the weight 52. Then, the friction force acting on the measurement counterpart member 52 from the sample base material 60 is measured by the load converter 54. The dynamic friction coefficient was calculated from the change in the friction force, and the surface friction coefficient of the sample base material 60 was evaluated.
Here, the material of the measurement counterpart member 52 is PTFE (polytetrafluoroethylene).

A stress measuring device 70 shown in FIG. 5 was used for measuring the amount of insertion force.
The stress measuring device 70 includes a channel tube 74 made of cylindrical PTFE having an inner diameter of 3.2 mm, an outer diameter of 4.4 mm, and a length of 400 mm, which is fitted into a channel guide 75 having a bent shape. A stress sensing measuring device 78 having a tube fixing metal rod 77 for pushing out a measurement sample S of a medical tube is disposed.
Here, the channel tube 74 is actually used in an endoscope.
The channel guide 75 has a tube diameter of 5 mm, and includes a straight portion 75a, a curved portion 75b, and a straight portion 75c having a length of 125 mm from the entrance side. The curvature radius (R in FIG. 5) outside the curved portion 75b is 50 mm, and the length of this curved portion is 39.25 mm. As a result, the straight portions 75a and 75c are bent 90 ° within the drawing sheet.

First, as the measurement sample S, the medical tube of each example and each comparative example was cut and the length was adjusted to 400 mm. Then, the rear end side of the measurement sample S is fixed to the front end of the tube fixing metal rod 77, inserted into the channel tube 74, and set at the tube installation position 76 that is inserted by 20 mm from the inlet of the linear portion 75a in the initial state. .
From this state, the measurement sample S is repeatedly inserted 10 times into the channel tube 74 at a moving stroke of 300 mm and a moving speed of 50 mm / sec.
When the measurement sample S advances into the channel tube 74, an insertion resistance is generated due to the tip Sa contacting the inner wall of the channel tube 74 positioned at the curved portion 75b of the channel guide 75, for example.
Then, the maximum insertion force in this repeated insertion was detected by a stress sensing measuring device 78 to which the tube fixing metal rod 77 was connected, and the average value of 10 times was taken as the amount of insertion force.

These measurement results and determination results are shown in Table 1 and FIG. The determination of the surface friction coefficient is in the range of 0 to 0.13, and the determination of the insertion force amount is in the range of 0N to 0.45N. The results are ○ (good) and × (outside the allowable range). (The following table is the same).
In the following, the surface friction coefficient may be represented by the symbol μ _sf , the insertion force amount may be represented by the symbol F _f , and the measured value may be represented by (μ _sf , F _f ). For example, (0.06, 0.30 N) means μ _sf = 0.06 and F _f = 0.30 (N).

According to Table 1, the maximum values of μ _sf and F _f were (0.34, 0.80 N) in the case of Comparative Example 1.
The measurement results of Examples 1 to 3 were (0.06, 0.31N), (0.06, 0.29N), and (0.07, 0.32N). In Examples 1 to 3, the minimum blending ratio (15 parts by weight) of the composite particles 2B and the minimum average circularity (0.90) of the base particles 2a are used, and the average particle size of the base particles 2a is 0.10 μm to 30 μm. _Therefore , both μ _sf and F _f substantially increase with an increase in the average particle diameter of the mother particles 2 a, but even in the maximum example 3, the μ _sf is about 0. It was 21 times and F _f was about 0.40 times.
The measurement results of Examples 4 and 5 were (0.04, 0.27N) and (0.07, 0.31N). In Examples 4 and 5, the minimum blending ratio (15 parts by weight) of the composite particles 2B, the maximum average particle diameter (30 μm) of the base particles 2a, and the average circularity of the base particles 2a are 1.00 and 0.95. It has changed to. Combined with the results of Example 3, in the order of Examples 3, 5, and 4, it is a measurement example in the case where the average circularity of the mother particle 2a is increased from 0.90 to 1.00. From the results, it can be seen that μ _sf and F _f are substantially decreased as the average circularity of the mother particle 2a is increased. That is, the largest mu _{sf, F f} of Example 3 In this third example.
The measurement results of Examples 6 and 7 were (0.07, 0.33N) and (0.09, 0.35N). In Examples 6 and 7, the minimum average circularity (0.90) and maximum average particle diameter (30 μm) of the mother particles 2a were changed, and the mixing ratio of the composite particles 2B was changed to 40 parts by weight and 70 parts by weight. Yes. When combined with the results of Example 3, it is a measurement example in the case of increasing the blending ratio of the composite particles 2B from 15 parts by weight to 75 parts by weight in the order of Examples 3, 6, and 7. These measurement results From Example 7, μ _sf and F _f are maximized in Example 7 in which the compounding ratio of the composite particles 2B is maximum. Moreover, although Example 7 was the largest in Examples 1-7, compared with the comparative example 1, ( _{micro |} micron _| mu) _sf was about 0.26 times and _Ff was about 0.44 times.
The measurement results of Examples 1 to 7 were all good results within the allowable range.
Further, the variation of μ _sf in Examples 1 to 7 is as extremely small as 0.05 (= 0.09−0.04).

The measurement result of Example 8 was (0.07, 0.33N). Example 8 is an example in which the material of the child particle 2b is changed to BN in Example 3, and the result is almost the same as that of Example 3. Therefore, it can be seen that MoS ₂ and BN are both substances having a layered structure and can reduce the surface friction coefficient in substantially the same manner.

Moreover, the measurement results of Comparative Examples 2 and 3 were (0.32, 0.79N) and (0.24, 0.70N). Comparative Examples 2 and 3 have the minimum compounding ratio (15 parts by weight) of the composite particles 2B and the minimum average circularity (0.90) of the base particles 2a, and the average particle diameter of the base particles 2a is 50 μm,. This is an example when the thickness is set to 05 μm. As for these measurement results, μ _sf is about 4.6 times and about 3.4 times, and F _f is about 2.5 times and about 2.2 times, respectively, with respect to Example 3. That is, even if the average particle diameter of the mother particle 2a is larger than 30 μm or smaller than 0.10 μm, μ _sf and F _f are remarkably increased and are out of the allowable range. Moreover, the value closer to the comparative example 1 which does not mix | blend the composite particle 2B is shown rather than Examples 1-3, and it turns out that the reduction effect of frictional force is scarce.
In addition, the measurement results of Comparative Examples 4 to 7 are (0.25, 0.71 N), (0.26, 0.71 N), (0.28, 0.77 N), (0.31,0), respectively. .78N). Since any one of the average particle diameter, average circularity of the mother particles 2a, the compounding ratio of the composite particles 2B, and the particle diameter ratio is outside the scope of the present invention, these are different from Example 7 in terms of μ _sf Are about 2.8 times, about 2.9 times, about 3.1 times, about 3.4 times, and F _f is about 2.0 times, about 2.0 times, about 2.2 times, about 2. times. It is dramatically increased by a factor of 2 and is outside the allowable range.

[Examples 9 to 14 of the second embodiment]
Table 1 shows the configurations of the base matrix 2A and the composite particles 12B of the medical tubes 11 of Examples 9 to 14 of the second embodiment.

As shown in Table 1, in Examples 9-14, Pebax (registered trademark) 6333SN01 (manufactured by Arkema) was used as the base matrix 2A, and PMMA (Soken) was used as the base particle 2a of the composite particle 12B. Chemical Co., Ltd.) was adopted. The composite particle 12B has a blending ratio of 15 parts by weight with respect to 100 parts by weight of the base matrix 2A, the average particle diameter of the mother particles 2a is 30 μm, the average circularity is 0.90, and the particle diameter ratios are both mother particles: Child particle = 10: 1.
The material of the child particles 12b of the composite particles 12B was changed to Al ₂ O ₃ , BaSO ₄ , SiC, WO ₃ , W, and BiO ₃ , respectively.

These measurement results and determination results are shown in Table 1 and FIG.
According to Table 1, the measurement results of Examples 9 to 14 are (0.10, 0.39N), (0.11, 0.38N), (0.10, 0.36N), (0, respectively. .11, 0.40 N), (0.09, 0.36 N), and (0.08, 0.34 N).
Although these measurement results were slightly larger than the measurement results of Example 3, they were good results within an allowable range.
Further, the variation of μ _sf in Examples 9 to 14 is as extremely small as 0.03 (= 0.11 to 0.08).
Further, compared to Comparative Example 1, μ _sf is about 0.29 times, about 0.32 times, about 0.29 times, about 0.32 times, about 0.26 times, about 0.24 times, F It can be seen that _f is about 0.49 times, about 0.48 times, about 0.45 times, about 0.50 times, about 0.45 times, and about 0.43 times, which are markedly reduced.

DESCRIPTION OF SYMBOLS 1,11 Medical tube 1a Outer surface 1b Inner surface 2,12 Composite material 2A Base matrix (polymer material)
2B, 12B Composite particle 2a Mother particle 2b, 12b Child particle

Claims (5)

A composite material comprising a polymer material containing one or more types of thermoplastic resin and a particle material composited on at least the surface of the polymer material,
The particulate material is
Mother particles having an average circularity of 0.90 or more and an average particle diameter of 0.1 μm or more and 30 μm or less;
A composite particle having an average particle size of 1/10 or less of the mother particle, and a child particle attached to the surface of the mother particle;
The composite material is characterized in that 15 parts by weight or more and 75 parts by weight or less are added to 100 parts by weight of the polymer material.   The composite material according to claim 1, wherein the child particles have a graphite type structure or a molybdenum sulfide type structure. The child particles are
Including one or more of aluminum oxide (Al ₂ O ₃ ), barium sulfate (BaSO ₄ ), tungsten oxide (WO ₃ ), tungsten (W), bismuth oxide (BiO ₃ ), and silicon carbide (SiC) The composite material according to claim 1.   A medical tube using the composite material according to claim 1.   A medical catheter comprising the medical tube according to claim 4.

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