JPH10113874A - Composite abrasive grain for biomaterial polishing, its manufacturing method and abrasive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide high precision surface finishing without forming a bulky polishing trace by fixing and compositing abrasive grinding grains a grain diameter of which is smaller than that of bioceramic particles and having biological compatibility on surfaces of the bioceramic particles having biological compatibility. SOLUTION: It is possible to firmly fix abrasive grinding grains 31 which are child particles on surfaces of bioceramic particles 30 having biological compatibility to be mother particles, and composite grinding grains 40 uniformly covered with the child particles 31 are formed on the surfaces of the mother particles 30. Binder resin as a binder 33 is formed on a surface of a film type base material 32, and a film type polishing material 34a arranged with the composite grinding grains 40 in a single layer on its upper surface is provided. Consequently, there is little possibility to transfer and adhere binder resin in a polishing article direction at the time of grinding process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite abrasive used for polishing the surface of a biological material such as an implant material for a biological implant, a method for producing the same, and a biological material abrasive. A composite abrasive that can form an implant material having a good affinity with a living body even when the living body material to be polished is implanted in the living body with little effect on the living tissue, and its production. Methods and biomaterial abrasives.

[0002]

2. Description of the Related Art When a living hard tissue is damaged or its normal function is lost due to illness, aging, or injury,
2. Description of the Related Art Techniques have been developed in which an artificially formed biomaterial (implant material) is implanted in a living body to restore its function.
For example, a surgical treatment method for repairing a bone defect by embedding an artificial bone or artificial joint made of metal or ceramic into a defective bone has been widely used. In addition, the artificial tooth root is embedded as an implant material in the tooth part that has come off due to tooth decay, etc., as a base, and crystallized glass is laminated on this base to form a denture, or made of metal or ceramic Restoration methods for fixing dentures are also widely used.

As properties required for implant materials for living hard tissues such as artificial bones and artificial tooth roots, it is essential that, as with general implant materials, firstly, they have excellent compatibility with living tissues. In other words, there is no harm to the living body such as toxicity, irritation and carcinogenicity even when it comes into contact with the living body, it does not induce blood coagulation, hemolysis or metabolic abnormalities, and dissolution or corrosion even under severe conditions in the living body It is required to be biochemically stable (bioinert) without causing deterioration.

[0004] As a second required characteristic, it is also essential to have a structural strength and a fracture toughness sufficient to withstand repeated fluctuating loads and to exhibit a predetermined function. Furthermore, it is also an important required characteristic that after implanting in the living body, it has a property of sufficiently binding with surrounding bone tissue and soft tissue, so-called tissue affinity (biocompatibility, bioactivity). . Further, in order to prevent infection of various organisms to the living body, physicochemical stability that enables sterilization is required.

The above-mentioned various implant materials (biomaterials) are embedded in a living body after grinding a material made of ceramic, metal, or the like into various shapes according to the purpose, polishing the surface and finishing the surface. Especially artificial joints, artificial bones,
In the case of implant materials for living hard tissues such as artificial teeth, careful polishing is required because the finished surface properties of the material greatly affect the abrasion resistance, lubrication properties, durability, fracture toughness, biocompatibility, etc. of the implant material. Processing has been implemented.

[0006] In the above polishing process, depending on the final processed shape, shape accuracy and processing efficiency of the biomaterial, a polishing method such as lapping or polishing using free abrasive grains, a polishing film using fixed abrasive grains, or the like is used. A polishing method is used. In particular, when precision polishing is required, a polishing film formed by coating the surface of a film base material with a resin in which fine abrasive grains made of diamond or hard ceramics are uniformly dispersed is generally used. Also,
When polishing natural teeth or various artificial teeth, abrasive grains of high hardness are dispersed in rubber and the tip is made of various shapes such as cylindrical, conical, truncated conical, disk-shaped, shell-shaped, etc. A point-type abrasive formed into a shape is widely used.

[0007]

However, in a conventional abrasive which is formed by coating the surface of a base material with a resin in which abrasive grains are dispersed, as the abrasive grain diameter becomes smaller, the surface energy increases and the abrasive grain size increases. Are easily aggregated, and it becomes difficult to uniformly disperse the abrasive grains in the resin. When using an abrasive that is fixed in a state in which the abrasive grains are aggregated, scars are easily formed on the biomaterial to be polished, and the structural strength and durability are greatly reduced. On the other hand, there is a problem that the abrasive particles themselves tend to fall off and the life of the abrasive material is shortened.

Further, as the abrasive grain size is reduced for precision polishing, the surface roughness of the abrasive film formed by coating also decreases, and the friction with the material to be polished at the time of polishing increases. Welding and fusing are likely to occur. Further, since it becomes difficult to discharge the polishing waste, clogging is easily caused, which has been a cause of shortening the life of the abrasive. Particularly, a binder component which is an impurity is easily welded, and when this fused biomaterial is implanted in a living body, a serious problem is likely to occur in a biological reaction such as an antibody reaction easily occurring in the living body.

In order to improve the dispersibility of the abrasive grains, a mixed spherical abrasive obtained by coating spherical particles with abrasive particles has been proposed, for example, as disclosed in Japanese Patent Application Laid-Open No. 1-205978. I have.

However, the mixed spherical abrasive has a so-called ordered mixture structure in which fine abrasive particles are simply adhered to the surface of large particles made of polymer beads with a weak bonding force. Therefore, the abrasive grains are liable to fall off, and the life of the abrasive using the mixed abrasive grains is short. Further, the mixed spherical abrasive is not intended for polishing a biomaterial, and its composition is not taken into consideration at all. Therefore, particle components that become impurities after polishing tend to adhere to the biomaterial, and the biomaterial is produced. When implanted in the body, there is a problem that the fusion strength with the surrounding tissue and the biocompatibility are reduced, and that the bioreaction is adversely affected.

In the case where a prosthetic material in which hard particles are dispersed in a soft material is polished using a conventional abrasive formed by dispersing abrasive grains in rubber, the prosthetic material in the Since only the soft material has a strong tendency to be selectively polished, it has been difficult to obtain a polished surface that is smooth and glossy and has good biocompatibility.

On the other hand, an abrasive obtained by depositing a diamond single crystal layer as a polishing abrasive layer on a surface of a ceramic sintered body (core material) by a vapor deposition method is widely used. Since the layer exists only on the surface of the abrasive, there is a problem that the life of the abrasive is extremely short. Also, for abrasives in which a polishing abrasive layer is coated on the surface of a core material formed into a predetermined shape with rubber or soft synthetic resin using an adhesive, similarly, since the abrasive layer is formed only on the surface, polishing is performed. There was a drawback that the life as a material was short.

The present invention has been made to solve the above problems, and has an excellent life (durability) and does not adversely affect the surface of a biomaterial even when the biomaterial is polished.
In addition, even when a polished biomaterial is implanted in a living body, it has little effect on living tissue and can form a biomaterial having good affinity with the living body, and a composite abrasive for polishing a biomaterial, and its production It is an object to provide a method and a biomaterial abrasive.

[0014]

Means for Solving the Problems In order to achieve the above object, the present inventors have prepared composite abrasive grains by combining various inorganic materials and polishing abrasive grains, and used the composite abrasive grains as free abrasive grains. The biomaterial was used to polish and comparatively investigate the effect on the biomaterial. Also, the above-mentioned composite abrasive grains are made into a sintered body, or fixed to the surface of a base material via a binder to prepare various abrasives, and the constituent material and manufacturing method of the abrasives are used to improve the life and durability of the abrasives. The effects of these materials and the characteristics of biomaterials such as implant materials were compared.

As a result, biocompatibility among inorganic materials,
In particular, hydroxyapatite (Ca
₁₀ (PO ₄ ) ₆ (OH) ₂ ) (hereinafter, abbreviated as HAP) or the like is bonded to the surface of bioceramic particles such as abrasive grains firmly using a high-speed air impact method to form composite abrasive grains. When prepared, the abrasive grains had good dispersibility and could be precisely polished without adversely affecting the surface of the biomaterial, and a long-life composite abrasive grain was obtained. In addition, the bioceramic component having excellent biocompatibility can be positively attached to the surface of the biomaterial while polishing the surface of the biomaterial such as an implant material. It has become clear that a long-lived biomaterial having excellent fusion strength with a living tissue can be obtained for the first time.

Further, even when the composite abrasive is fixed to the surface of the base material to form an abrasive, or when the composite abrasive is formed and sintered to obtain an abrasive, the bonding between the bioceramic particles and the abrasive is performed. Because of high strength, less abrasive particles fall off,
A long-life abrasive is obtained. It has been found that even when the biomaterial is polished using the above abrasive, the bioceramic component adheres to the surface of the biomaterial, so that a biomaterial having excellent biocompatibility can be obtained.

The present invention has been completed based on the above findings. That is, the composite abrasive for polishing a biomaterial according to the present invention is obtained by fixing a bioabrasive abrasive having a particle size smaller than the bioceramic particles and a biocompatible abrasive to the surface of biocompatible ceramic particles. It is characterized by having

The biocompatible bioceramic particles include bioactive hydroxyapatite (H
AP), tricalcium phosphate (TCP), living glass,
It is preferable to use crystallized glass and at least one selected from the group consisting of alumina, zirconia, calcium aluminate, and aluminosilicate, which are biologically inactive.

The materials having biocompatibility include:
As described above, the material is roughly classified into a material having biological activity and a material having biological inactivity. A material having bioactivity is a material that has a positive effect on a living body, such as good compatibility (affinity) with a living tissue. On the other hand, a biologically inert material is a material that is inactive in a living body and has little adverse effect on living tissues. In the present invention, any of the above-mentioned bioactive materials and bioinert materials can be used, but it is particularly preferable to use bioactive materials.

Further, it is preferable that the average particle diameter of the bioceramic particles having biocompatibility is at least 5 times the average particle diameter of the abrasive grains.

The biocompatible abrasive grains may be composed of at least one selected from diamond, alumina, zirconia, silicon nitride, and silicon carbide.

Further, the method for producing a composite abrasive for polishing a biomaterial according to the present invention is characterized in that the surface of the bioceramic particles having biocompatibility is coated with a high-speed airflow impact method so as to cover the surface of the bioceramic particles with the biocompatible polishing abrasive. The abrasive grains are fixed to the surface of the bioceramic particles.

Further, the first biomaterial abrasive according to the present invention has a smaller particle diameter than the bioceramic particles on the surface of biocompatible bioceramic particles.
In addition, a composite abrasive grain, which is obtained by fixing and polishing bioabrasive abrasive grains, is elastically supported and fixed to the base material surface via a binder.

Here, the substrate is a film-like substrate composed of at least one selected from polyethylene terephthalate (PET), polyimide and polycarbonate, or at least one selected from paper, hard rubber, soft synthetic resin and metal. A disk-shaped substrate made of

The binder is preferably composed of at least one selected from synthetic polymers such as synthetic rubber and synthetic resin, chemically treated biomaterials and natural polymers.

A second biomaterial abrasive according to the present invention is characterized in that biocompatible polishing abrasive grains are dispersed in a matrix sintered body made of biocompatible bioceramics.

Further, the third biomaterial abrasive according to the present invention has a smaller particle size than the bioceramic particles on the surface of the biocompatible ceramic particles.
In addition, it is characterized by comprising a sintered body of composite abrasive grains obtained by fixing and compounding bioabrasive abrasive grains.

Here, the average particle size of the abrasive grains is 10 μm.
Or less, more preferably 5 μm or less. Further, it is preferable that high-toughness ceramic particles having a smaller particle diameter than the abrasive grains are fixed on the surface of the composite abrasive grains to form a composite. Further, the high toughness ceramic may be composed of at least one of partially stabilized zirconia (PSZ) and alumina.

Further, the method for producing the biomaterial abrasive is described in the following.
The composite abrasive grains are prepared by fixing the abrasive grains to the surface of the bioceramic particles by a high-speed airflow impact method so that the surface of the biocompatible bioceramic particles is coated with the biocompatible abrasive grains. The obtained composite abrasive grains are subjected to pressure molding, and the obtained compact is sintered in a non-oxidizing atmosphere. It is also possible to manufacture the composite abrasive grains by a hot press method in which the composite abrasive grains are pressed and sintered at the same time. In the above-mentioned manufacturing method, it is preferable to use a composite abrasive grain in which high toughness ceramic particles having a smaller particle diameter than the polishing abrasive grain are further fixed to the surface of the composite abrasive grain using a high-speed air current impact method.

The biocompatible bioceramic particles used for forming the composite abrasive for polishing a biomaterial of the present invention include bioactive hydroxyapatite (HAP) and tricalcium phosphate (TCP). , Biological glass, crystallized glass, biologically inert alumina, zirconia, calcium aluminate, aluminosilicate and the like can be used. These bioceramic particles function as nucleus (core) particles for preventing agglomeration of the fixed abrasive grains. In the case where bioceramic particles that are bioactive are used, they are the main components that function to increase the biocompatibility of the biomaterial by attaching to the biomaterial to be polished.

Of the above various bioceramic particles,
In particular, hydroxyapatite (HAP) has a crystal structure similar to that of bone tissue of a living body, and is most suitable for imparting bone tissue affinity to a biomaterial. In addition, since TCP has a higher solubility in body fluids than HAP, TCP attached to the surface of a biomaterial serves as a local supply source of Ca and P, thereby increasing the bone formation rate of osteoblasts. ,preferable.

The average particle size of the biocompatible bioceramic particles is at least 5 times, preferably at least 10 times the average particle size of the abrasive grains in order to uniformly fix the abrasive grains on the surface. Desirably. The shape of the bioceramic particles is not particularly limited, but is preferably spherical.

On the other hand, as abrasive grains, so-called biocompatible abrasive grains having no toxicity to living bodies are used. Specific examples of the abrasive grains include medical ceramic particles that are chemically stable even in a living body, such as diamond, alumina, zirconia, silicon nitride, and silicon carbide. The particle size of the abrasive grains of the above abrasive grains varies depending on the properties of the finished polishing surface of the target biomaterial, but the approximate average particle size is about 0.01 to 50 μm, and those having a narrow particle size distribution are sometimes used. preferable. In particular, in order to improve the finishing accuracy of the polished surface, the average particle size is 10 μm.
It is preferable to use abrasive grains of m or less, preferably 5 μm or less, and it is more preferable to use abrasive grains having a uniform particle size in order to enhance the uniformity of the polished surface. The type, particle size, and particle size of these abrasive grains are appropriately selected depending on biocompatibility and polishing accuracy required for a biomaterial.

The mixing ratio of the biocompatible bioceramic particles and the abrasive grains varies depending on the size of each particle, but the entire surface of the relatively coarse bioceramic particles is finely polished. It is desirable to mix them in such a ratio as to cover the abrasive grains.

The composite abrasive for biomaterial polishing according to the present invention comprises:
The bioceramic particles are manufactured by fixing the abrasive grains to the surface of the bioceramic particles by a high-speed airflow impact method so that the surface of the biocompatible bioceramic particles is coated with the biocompatible abrasive grains.

FIGS. 1 and 2 are a system diagram and a main part side, respectively, showing an example of the structure of a high-speed airflow impact type powder surface reforming apparatus (hybridizer) 1 used for producing the above-mentioned composite abrasive grains. It is sectional drawing. This powder surface reforming device 1
Is a method in which other solid particles (child particles) having a smaller particle size than the parent particles are firmly fixed to the surface of the core solid particles (base particles) by dry and mechanical means. This is an apparatus developed for efficiently producing functional composite particles in a short time.

The powder surface reforming apparatus 1 includes a main casing 2, a rear cover 3 and a front cover 4, a rotor 5 rotating at high speed in the casing 2, and a predetermined interval between the outer periphery of the rotor 5. And a hammer-type or blade-type impact pin 6 radially provided around
A rotating shaft 7 rotatably supporting the inside of the casing 2 and a collision ring 8 which is provided along the outermost raceway surface of the impact pin 6 and is provided around the impact pin 6 with a certain space. It is configured with.

As the collision ring 8, rings of various shapes, such as a concavo-convex type or a circumferential plane type, are appropriately used.
The gap between the outermost raceway surface of the impact pin 6 and the collision ring 8 is adjusted to 0.5 to 20 mm, depending on the type of the object to be modified and the processing capacity of the surface modification device. Further, an opening / closing valve 9 is provided which fits closely with a modified powder discharge port provided by partially cutting out the upper part of the collision ring 8. Further, a valve shaft 10 of the opening / closing valve 9 and this valve shaft 10 are connected to each other. An actuator 11 that drives and operates the on-off valve 9 through the intermediary is provided.

A circulation circuit 12 which connects an inlet 12a opening to a part of the inner wall of the collision ring 8 and an outlet 12b opening to the front cover 4 located at the center of the rotor 5 to form a closed circuit; A raw material hopper 13, a raw material supply chute 14 for communicating the raw material hopper 13 with the circulation circuit 12, and an on-off valve 15 provided in the middle of the chute.
And an impact chamber 16 provided between the outer periphery of the rotor 5 and the collision ring 8.

A modified powder discharge pipe 17 and a bag collector 18 are provided on the secondary side of the on-off valve 9. Also,
A known preprocessor 19 such as various mixers and an automatic mortar used when it is necessary to preliminarily attach child particles to mother particles to form a mixed powder, and the mixed powder obtained by the preprocessor 19 A raw material measuring feeder 20 for supplying a fixed amount to the surface reforming apparatus 1 is additionally provided.

The above-mentioned powder surface reforming apparatus 1 is designed to be capable of automatic batch operation by a time control device (not shown). When the surface reforming apparatus 1 is operated for a long time, or when the processing capacity is large, a powder separating device such as a cyclone may be provided instead of the bag collector 18, or a plurality of bag filters may be used. The modified powder is configured to be connected in parallel or to discharge the modified powder using an exhaust fan (not shown).

Since the powder surface reforming apparatus 1 shown in FIGS. 1 and 2 is a completely batch-type reforming apparatus, the ambient temperature in the apparatus may increase as the powder processing time elapses.
Therefore, a jacket 21 is formed inside the collision ring 8,
It is preferable that the temperature inside the shock chamber 16 and the circulation circuit 12 can be controlled to be constant by flowing cooling water or the like through the jacket 21. Further, by previously replacing the interior of the impact chamber 16 and the circulation circuit 12 with an inert gas, it is possible to perform the immobilization of particles by the present apparatus in an inert gas atmosphere. Further, in the powder surface reforming apparatus 1 used in the method of the present invention, a portion where powder contacts (a so-called powder contact portion), in particular, the surface of the rotor 5, the impact pins 6, the impact ring 8, and the inner surface of the circulation circuit 12 It is preferable to use a biosafety material such as alumina or zirconia as a constituent material.

When the immobilization treatment of foreign particles is carried out using the powder surface reforming apparatus 1, the apparatus is operated in the following manner.

First, the on-off valve 15 disposed in the middle of the raw material supply chute 14 is closed, and the on-off valve 9 at the modified powder discharge port is also closed. Drive, for example, at an outer peripheral speed of 60-100 m
The rotor 5 is rotated at about / sec. At this time, an abrupt air flow is generated with the rotation of the impact pin 6, and a fan effect based on the centrifugal force of the air flow causes the circulation circuit 1 to pass through an inlet 12 a opening on a part of the inner wall of the collision ring 8.
An outlet 12 opening at the center of the front cover 4 via
A circulation flow returning from b to the shock chamber 16 is formed.

This air flow is a complete self-circulating flow, and the amount of circulating air generated per unit time at this time is extremely large compared to the total volume of the shock chamber and the circulating system. An enormous number of airflow circulation cycles are formed in time. For example, a rotor with an outer diameter of 118 mm
The circulation air volume when rotating at an outer peripheral speed of m / sec is 0.
48 m ³ / min, and the number of air circulation cycles per unit time is 774 times / min. Since the amount of circulating air is proportional to the outer peripheral speed of the rotor, the number of air circulation cycles per unit time also increases in proportion to the outer peripheral speed of the rotor.

Here, in the case of carrying out the immobilization treatment performed by the method of the present invention, the outer peripheral speed of the rotor is 30 to 150 m /
It is preferably set in the range of sec, more preferably in the range of 40 to 80 m / sec. When the outer peripheral speed is less than 30 m / sec, a sufficient airflow is not generated in the circulation circuit, and the processing time becomes longer particularly when particles having a large specific gravity difference are processed, and the sufficient amount of air required for fixing the particles is required. It is difficult to apply a strong impact force, and the processing efficiency is reduced. On the other hand, 15
It is difficult to obtain an outer peripheral speed exceeding 0 m / sec because of limitations in the structure of the apparatus, and it is difficult in terms of mechanical structure, and particles having biocompatibility as base particles are easily broken (crushed). The immobilization process is completed in about 1 to 5 minutes.

With the circulating flow as described above, the on-off valve 15 is then opened, and the mixed powder of the base particles and the child particles is charged into the raw material hopper 13 via the measuring feeder 20 in a short time. Then, the mixed powder enters the shock chamber 16 via the raw material hopper 13 and the raw material supply chute 14. After confirming that no mixed powder remains in the raw material hopper 13, the on-off valve 15 is closed. When the automatic batch operation is performed, the time required for charging the mixed powder is measured in advance and input to the time control device.

The mixed powder introduced into the impact chamber 16 is instantaneously hit by an impact pin 6 attached to a rotor 5 rotating at a high speed in the impact chamber 16, and is further applied to a peripheral collision ring 8. collide. Then, it is entrained by the circulating airflow, returns to the shock chamber 16 again around the circulation circuit 12, and receives the same impact action again. By repeatedly receiving the striking action in this manner, a uniform immobilization process is performed in a short time of several tens seconds to several minutes. as a result,
As shown in FIG. 3, abrasive abrasive grains 31 as child particles can be firmly fixed on the surface of biocompatible bioceramic particles 30 as mother particles, and child particles 31 can be uniformly formed on the surface of mother particles 30. The coated composite abrasive grains 40 are formed.

After the completion of the fixing process, the on-off valve 1
5, the opening / closing valve 9 of the modified powder outlet is moved to the position shown by the broken line and opened to discharge the composite abrasive grains. The composite abrasive grains are subjected to the impact chamber 16 and the circulation circuit 12 in a short time of several seconds by centrifugal force acting on the particles themselves.
After that, the air is discharged from the apparatus main body, and further collected by the bag collector 18 via the discharge pipe 17.

Thus, the composite abrasive grains 40 produced by the powder surface reforming apparatus 1 based on the high-speed air-flow impact method simply have child particles on the surface of the base particles like mixed abrasive grains prepared by a conventional mixing apparatus. This is not a so-called ordered mixture in an attached (blown) state, but a composite abrasive grain in which child particles are embedded and firmly and densely fixed on the surface of a base particle. Therefore, even when the obtained composite abrasive grains are subjected to pressure molding or heat treatment, the composited two components are less likely to be re-separated, and each component is less likely to aggregate to form coarse particles.

The composite abrasive grains prepared as described above can be used as they are as free abrasive grains for lapping or polishing, and the composite abrasive grains are further elastically bonded to the surface of various substrates via a binder. It can also be used as a film-like abrasive or a disk-type abrasive (polishing tool) by being supported and fixed.

That is, a polishing film can be formed by fixing the above-mentioned composite abrasive grains on the surface of a film-like base material such as polyethylene terephthalate (PET), polyimide or polycarbonate.

Further, by immobilizing the composite abrasive grains on the surface of a disk-shaped substrate such as paper, hard rubber, soft synthetic resin, and metal, a disk-type abrasive can be obtained.

Here, as the binder, synthetic polymers such as synthetic rubber and synthetic resin, which are less toxic to biomaterials, chemically treated biomaterials and natural polymers are used. Specific examples of the above synthetic rubber include polyvinyl chloride,
There are silicone, polyurethane, polyolefin, and the like. Specific examples of the synthetic resin include polyvinyl chloride, polypropylene, polystyrene, polycarbonate, polyethylene, hydroxyethyl methacrylate, polymethyl methacrylate, polyvinyl alcohol, Teflon, polysulfone, polyester, polypropylene, and nylon. , Polyglycolic acid and the like.

The composite abrasive produced as described above is mixed with a binder such as a binder resin, a curing agent, and a solvent to form a coating liquid. It is applied to the disk-shaped substrate surface. As the application means, for example, a roll coater such as a gravure coater or a blade coater is used. Then, the applied coating liquid is heated and dried, and the resin component as a binder is cured, whereby a film-shaped or disk-shaped biomaterial abrasive in which the composite abrasive grains are integrally fixed to the substrate surface is prepared. You.

Here, the coating thickness of the coating liquid is 5 to 100.
It is set to about μm. Depending on the thickness of the coating liquid, a single-layer or multilayer polishing abrasive layer is formed on the substrate surface. FIG. 5 shows that the composite abrasive 40
Is a cross-sectional view of a film-like abrasive 34b having a multilayer structure formed by arranging two or more layers.

In the abrasive 34 b shown in FIG. 5, a binder resin as the binder 33 is present on the surface of the base material 32 so as to cover the composite abrasive grains 40. Therefore, when the polishing target material is polished with the composite abrasive grains 40, the resin component easily migrates to the polishing target material side. For this reason, it is preferable to use a medical polymer material such as an acrylic resin having little effect on the living body as the binder resin.

As another method for producing an abrasive, first,
It is also possible to apply a binder resin as a binder to the surface of the base material and then fix the composite abrasive grains by an electrostatic adhesion method. FIG. 4 shows an abrasive prepared by such a method, in which a binder resin as a binder 33 is formed on the surface of a film-like base material 32, and composite abrasive grains 40 are arranged in a single layer on the upper surface thereof. FIG. 4 is a cross-sectional view showing a polishing material 34a.

In the abrasive material 34a shown in FIG. 4, the composite abrasive grains 40 fixed on the base material 32 have a single-layer structure, and the upper half of the composite abrasive grains 40 has no binder resin. The possibility that the binder resin migrates and adheres in the direction to be polished is small. Therefore, the selection range of the binder resin is wider than that of the abrasive 34b shown in FIG. 5, but the binder resin may partially exist above the composite abrasive grains 40. Polyesters, polyurethanes and copolymers thereof, which have little effect on water resistance, are preferred. The thickness of the binder resin applied to the substrate is set to be equal to or less than the diameter of the composite abrasive grains 40.

The object of the invention of the present application is achieved not only by the above-mentioned composite abrasive grains and the abrasive material having the composite abrasive grains integrally fixed to the base material, but also by the following abrasive materials. . That is, the mixed abrasive grains composed of the biocompatible bioceramic particles and the abrasive grains were press-formed and sintered, and the biocompatible abrasive grains were dispersed in a matrix sintered body composed of the bioceramics. Pressure-forming composite abrasive grains composed of abrasives or the above-mentioned bioceramic particles, abrasive grains and, if necessary, high toughness ceramic particles such as partially stabilized zirconia (PSZ).
The same effect can be exhibited by the sintered abrasive.

The mixed abrasive grains composed of the bioceramic particles and the abrasive grains are prepared by, for example, a high-speed stirring type mixer. The high-speed stirring type mixer is configured by attaching a plurality of high-speed rotating stirring blades at a lower portion of a cylindrical container, and uniformly mixes the raw material mixture put in the container by a short operation of about 1 to 5 minutes. Can be dispersed and mixed. Further, the composite abrasive is prepared by a powder surface reforming apparatus utilizing the high-speed airflow impact method.

As the above-mentioned pressure molding method, there are a uniaxial pressure (UAP) molding method using a usual mold pressing device and a cold isostatic pressure (CIP) molding for applying a molding pressure isotropically to a mixed powder. A law can be adopted. It should be noted that a hot press (HP) method or a hot isostatic pressure (HIP) method in which the above-described molding operation and sintering operation are performed simultaneously can also be used.

When sintering is performed after the uniaxial pressure molding, first, the mixed powder is compacted at a molding pressure of 10 to 200 MPa to a pressure of 1 to 200 MPa.
The resulting compact is sintered under a non-oxidizing atmosphere such as argon gas at a temperature of 900 to 1500 ° C. for 1 to 3 hours.

When sintering is performed after cold isostatic pressing (CIP), first, the mixed powder is uniaxially pressed at 10 to 100 MPa, and then pressed at a pressure of 20 to 300 MPa.
It isotropically compressed for 15 minutes to form a molded body, and the obtained molded body is similarly sintered at a temperature of 900 to 1500 ° C. for 1 to 3 hours.

When the molding operation and the sintering operation are simultaneously performed by the hot press method, the mixed powder is subjected to a pressure of 20 to 100 MPa in a non-oxidizing atmosphere such as argon gas.
a, Pressure sintering is preferably performed at a temperature of 700 to 1450 ° C. for 5 to 30 minutes.

Among the various forming and sintering methods, according to the hot press (HP) method, the sintering temperature is relatively low, and a dense sintered body is easily obtained even if the sintering time is shortened. have. Here, when using hydroxyapatite (HAP) particles and abrasive grains as biocompatible particles, and sintering using partially stabilized zirconia (PSZ) as high toughness ceramic particles, generally, P
By the addition of SZ, a part of the HAP particles is changed to tricalcium phosphate, and a crystal change of PSZ is likely to occur. However, due to the features of the hot press method, there is an advantage that these changes can be suppressed and prevented.

In particular, on the outer surface of the composite abrasive formed by fixing the abrasive grains to the outer surface of the bioceramic particles, partially stabilized zirconia (biocompatible) having a smaller particle diameter than the abrasive grains In the case where abrasive grains are formed by pressing and then sintering composite abrasive grains obtained by compounding high toughness ceramic particles such as PSZ) particles, a continuous phase consisting of the above high toughness ceramic particles is formed in the abrasive structure. Is done. Therefore, the holding strength of the abrasive grains and the toughness of the abrasive are increased, and an abrasive having a long life and excellent durability is obtained.

According to the composite abrasive for polishing a biomaterial and the abrasive according to the present invention, a bioceramic having bioactivity is contained as a constituent material, and the bioceramic is polished when the biomaterial to be polished is polished. The components can be positively attached to the biomaterial. Therefore, when the biomaterial is implanted in the living body, the affinity of the living tissue becomes good, and the fusion strength of the biomaterial can be greatly improved.

Since the abrasive grains are firmly fixed to the surface of the bioceramic particles, the abrasive grains do not aggregate to form coarse abrasive grains. Therefore, even if the biomaterial is polished, no coarse polishing marks are formed, and a highly accurate surface finish can be obtained. Furthermore, since abrasive grains are less likely to fall off, an abrasive material having a long life and excellent durability can be obtained.

[0070]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described more specifically with reference to the following examples.

First, composite abrasive grains were prepared by compounding bioceramic particles and abrasive grains according to the following procedure.
That is, spherical hydroxyapatite (HAP) particles (manufactured by Mitsubishi Materials KK) having a maximum particle diameter of 20 μm and an average particle diameter of 9.32 μm are prepared as bioceramic particles having bioactivity, and a temperature of 800 is used as a pretreatment. ° C
By heating for 2 hours, water and volatile impurities adsorbed on the particles were removed, and the structural strength was increased by forming a calcined body.

FIG. 6 is a scanning electron micrograph showing the particle structure of the spherical HAP particles subjected to the above pretreatment. The spherical HAP particles are composed of an aggregate of fine primary particles having a particle size of about 0.5 μm, and it can be observed that a large number of irregularities are present on the surface. No change in the shape and size of the particles was observed before and after heating in the pretreatment. Also, HA
The chemical composition of the P particles did not change before and after heating, and the Ca / P molar ratio calculated from the analytical values of CaO: 55.8% and P ₂ O ₅ : 42.3% was the Ca / P molar ratio of HAP. Of 1.67. When a sintered body is produced using HAP, it is important that the Ca / P molar ratio does not fall below the theoretical value and that the crystallinity is sufficiently high.

On the other hand, the abrasive grains have an average grain size of 0.1 μm.
Of diamond particles (manufactured by De Beers Co.) was prepared and subjected to a temperature of 1000 in an argon gas atmosphere as a pretreatment.
C. for 2 hours to remove adsorbed water and volatile impurities. FIG. 7 is a scanning electron micrograph showing the particle structure of the diamond particles subjected to the above pretreatment.

Next, the spherical HAP pretreated as described above
The particles and the diamond particles are weighed such that the mixing ratio is 10: 3 by weight, and the mixture is mixed with a high-speed stirring mixer (O.I.
M. Dither: K. K. OMD-O manufactured by Nara Machinery Works
Abrasive HAP particles are coated with diamond particles and mixed abrasive grains (ordered mixture)
Was prepared. Here, the blade rotation speed of the high-speed stirring type mixer was 800 rpm, the blade peripheral speed was 2.5 m / sec, and the processing time was 5 minutes.

Next, the mixed abrasive grains prepared as described above were mixed with a high-speed air current impact type powder surface reforming apparatus (Hybridizer, HYB-O type, K.K.) as shown in FIG. 1 and FIG.
K. (Nara Machinery Co., Ltd.) to firmly fix (composite) the diamond particles so that the surface of the relatively large spherical HAP particles is covered with the fine diamond particles (hereinafter referred to as HYB treatment). And Figure 3
The composite abrasive grains for the examples as shown in Table 1 were prepared. The processing conditions in the reformer (hybridizer) were as follows: the rotor rotation speed was 10,000 rpm, and the rotor peripheral speed was 60.
m / sec and the processing time were set to 5 minutes.

FIG. 8 is an electron micrograph showing the particle structure of a composite abrasive formed by compounding a mixed abrasive in which the mixing ratio of HAP particles and diamond particles is 10: 3.
In each case, it can be seen that the diamond particles are firmly fixed so as to completely cover the surface of the coarse spherical HAP particles. In particular, the average diameter of the diamond particles is 0.1 μm
In the process of compounding by the high-speed airflow impact method, diamond particles bite into the recesses on the surface of the spherical HAP particles due to the impact force during the compounding by the high-speed airflow impact method, and the HAP is formed by the so-called mechanical anchoring (mechanical interlocking) effect.
It is easily presumed that the particles and the diamond particles are composited with sufficient bonding strength.

On the other hand, as a comparative example, the raw material mixture in which the compounding ratio of the HAP particles and the diamond particles was 10: 3 as described above without performing the compounding by the high-speed air current impact method was used in accordance with the ordinary mixing method. The mixture was treated to prepare mixed abrasive grains for a comparative example. That is, each raw material mixture was mixed with a high-speed stirring mixer (OMD-0, KK Nara Machinery Co., Ltd., OM dither) to prepare mixed abrasive grains for a comparative example.

The high-speed stirring type mixer is provided with a stirring blade (blade) rotating at a high speed on the bottom of a cylindrical mixing vessel.
This is a stirring mixer generally used for uniformly dispersing and mixing a plurality of different raw material powders in a short time of about 1 to 3 minutes (hereinafter referred to as OMD treatment).

The processing conditions of the high-speed stirring type mixer for preparing the mixed abrasive grains of the comparative example were as follows: the rotation speed of the stirring blade was 800 rpm, and the peripheral speed of the stirring blade was 2.5 m / sec.
The processing time was set to 5 minutes.

Next, an abrasive (abrasive film) was manufactured by fixing the composite abrasive grains according to the examples and the mixed abrasive grains according to the comparative examples prepared as described above to the surface of the base material.

Example 1 While a 75 μm thick PET (polyethylene terephthalate) resin film was prepared as a base material, a binder resin as a binder was used in the following ratio with respect to the composite abrasive grains prepared as described above. The curing agent and solvent were weighed.

[0082]

[Outside 1]

Then, a mixed solution comprising the binder resin, the curing agent and the solvent having the above composition ratio is mixed with the PE as the base material.
After applying a thickness of about 10 μm on a T resin film, the composite abrasive grains are adhered to the resin layer by using an electrostatic adhesion method, and the resin layer is cured by heat treatment at a temperature of 60 ° C. for 48 hours. As shown in FIG. 4, an abrasive (abrasive film) 34a according to Example 1 was prepared.

FIG. 9 is a scanning electron microscope photograph showing the particle structure of the laminated portion of the abrasive (polishing film) prepared as described above. As shown in FIGS. 4 and 9, in the polishing film 34 a according to Example 1, a structure in which the surface of the HAP particles serving as nuclei of the composite abrasive grains 40 are completely covered with diamond particles can be confirmed. Further, as shown in FIG. 9, a structure in which the composite abrasive grains are fixed in a single particle layer on a film base material coated with a binder resin exhibiting black color can be observed.

Example 2 While a PET (polyethylene terephthalate) resin film having a thickness of 75 μm was prepared as a base material, the following ratio was used as a binder for 100 parts by weight of the composite abrasive grains prepared as described above. A binder resin, a curing agent and a solvent were added and uniformly mixed to prepare a coating liquid.

[0086]

[Outside 2]

Then, after applying a coating liquid comprising the composite abrasive grains having the above composition ratio, a binder resin, a curing agent and a solvent in a thickness of 10 to 20 μm on the PET resin film as the base material, By heat-treating at a temperature of 60 ° C. for 48 hours to cure the resin layer, an abrasive (abrasive film) b according to Example 2 as shown in FIG. 5 was prepared.

FIG. 10 is a scanning electron micrograph showing the particle structure of the laminated portion of the abrasive (polishing film) according to Example 2 prepared as described above. As shown in FIGS. 5 and 10, in the polishing film 34 b according to the second embodiment, the composite abrasive grains 40 are fixed in a one-layer or two-layer structure on the surface of the film-like base material 32 depending on the coating thickness of the coating liquid. It was possible to do. Also, the surface of each composite abrasive grain 40 has a binder 3
No. 3 was coated with the binder resin.

According to the polishing films of Examples 1 and 2, fine abrasive grains are firmly fixed on the outer surface of coarse HAP particles without agglomeration. The surface can be polished with high finishing accuracy. In addition, bioactive HAP particles can be positively adhered to the implant material during polishing, and the bioactive surface treatment of the implant material can be performed while performing polishing.

Further, it is possible to form an implant material which has a small amount of binder resin which is melted and adheres to the surface of the object to be polished and which is less harmful to living bodies. Further, the clogging of the polishing film due to the polishing debris is small, and the life and durability of the polishing material can be greatly extended. In particular, since there is no agglomeration of the abrasive grains, it is less likely that polishing marks are generated on the object to be polished to lower the strength.

Further, since the bonding strength between the abrasive grains and the HAP particles is high, the abrasive grains are less likely to fall off, and the life of the polishing film is greatly improved.

On the other hand, in the polishing film using the mixed abrasive of the comparative example prepared by mixing the spherical HAP particles and the diamond particles by the conventional mixing method without performing the composite fixing treatment by the high-speed airflow impact method. Has a lower bonding strength between the spherical HAP particles and the diamond particles, so that the life of the polishing film is 45 to 6 compared with the polishing material according to the example.
It was in the range of 5%.

Next, an embodiment of an abrasive in which abrasive grains are dispersed in a matrix sintered body made of bioceramic having bioactivity will be described.

Example 3 Hydroxyapatite (HAP) particles having an average particle diameter of 12 μm (amorphous HAP aggregates manufactured by Sigma) as bioceramic particles having bioactivity were prepared. Are 1-2 μm (sample 1), 3-6 μm (sample 2), 6-12 μm (sample 3), 20-30 μm (sample 4) and 30-40 μm
Five kinds of diamond particles (De Bee) of (Sample 5)
rs) and a pretreatment by heating was performed in the same manner as in the example.

The HAP particles manufactured by Sigma Co., Ltd. were subjected to a component analysis using a powder X-ray diffractometer (Model MXP3 manufactured by Mac Science Co., Ltd.). CaHP
It was confirmed that O ₄ ) was contained in a large amount of about 20% by weight.

Next, the above-mentioned HAP particles and the respective diamond particles were mixed and mixed so that the mixing ratio thereof was 10: 3 by weight to prepare five types of mixed abrasive grains having different abrasive particle diameters. The mixing operation was performed using a high-speed stirring mixer (OM Dither: OMD-O manufactured by KK Nara Machinery Co., Ltd.).
), The blade rotation speed was set to 800 rpm, the blade peripheral speed was set to 2.5 m / sec, and the processing time was set to 5 minutes.

Next, each of the obtained mixed abrasive grains was subjected to a uniaxial pressing machine (WPM-2 type manufactured by Applied Power Japan) with an inner diameter of 1 mm.
It is filled into a 5 mm die and uniaxially pressed for 5 minutes at a pressure of 9.8 MPa, and is 15 mm in diameter × 11.77 to 13.0 in height
A 5 mm cylindrical compact was obtained.

Next, the process proceeds to a step of sintering each of the obtained compacts. Here, if the above compact is sintered in an atmosphere in which even a trace amount of oxygen is present, the diamond particles are oxidized. Therefore, the inside of the furnace is sufficiently degassed using a hot press (manufactured by NEMS), and then the atmosphere is changed to an argon atmosphere. After the adjustment, each of the molded bodies was sintered at a temperature of 1150 ° C. for 2 hours to produce each biomaterial abrasive according to Example 3.

Next, each of the above-mentioned biomaterial abrasives was processed into a point-type abrasive and attached to the tip of a dental rotary abrasive tool.
A dental feldspar porcelain (composition formula: Na ₂ Al ₂ Si ₆ O ₁₈ ), which is a biomaterial, is polished at a rotation speed of 10,000 rpm, and the finished polished surface has a surface roughness (JIS B 060).
The arithmetic average roughness (Ra) specified in Table 1 was measured, and Table 1 below was measured.
Were obtained.

[0100]

[Table 1]

As is clear from the results shown in Table 1 above,
According to the abrasives according to Samples 2 to 5, the finished surfaces of the biomaterials were all small in surface roughness, and polished surfaces with high finishing accuracy were obtained. Ultrafine HAP particles of a microscopic level are firmly adhered to the surface of the biomaterial using the abrasive according to Samples 2 to 5. Particularly, in the biomaterial using the abrasive of Sample 3, HAP is applied to the surface of the material. The state in which was adhered could be clearly observed with the naked eye. Therefore, excellent affinity (fusion strength) can be obtained when the biomaterial is implanted in a living body.

On the other hand, a sintered body having a certain degree of strength could not be obtained from the abrasive according to Sample 1 using ultrafine diamond particles having a particle diameter of 1 to 2 μm as abrasive grains.

This is because when the particle size of the diamond particles as the abrasive particles is extremely small as compared with the particle size of the HAP particles, even if the mixing by the conventional stirring and mixing method (OMD treatment) is performed. This is considered to be because diamond particles tend to cover the entire surface of the HAP particles densely, and sintering becomes difficult when sintering is performed after pressing and molding.

Next, an embodiment of an abrasive obtained by pressing and sintering mixed abrasive grains or composite abrasive grains composed of bioceramic particles, abrasive abrasive grains and selectively added high toughness ceramic particles. Will be described.

Example 4 As particles having biological activity, spherical hydroxyapatite (H) having a maximum particle size of 20 μm and an average particle size of 9.32 μm was used.
AP) Particles (manufactured by Mitsubishi Materials KK) are prepared and subjected to a heat treatment at a temperature of 800 ° C. for 2 hours as a pretreatment to remove moisture and volatile impurities adsorbed on the particles and to provide a calcined body. To increase the structural strength.

The abrasive grains have an average particle diameter of 1 to 2 μm.
Diamond particles (manufactured by De Beers) were prepared.

On the other hand, as biocompatible high toughness ceramic particles, partially stabilized zirconia (PSZ) powder containing 3 mol% of yttria (Y ₂ O ₃ ) and having an average particle diameter of 0.12 μm (Asahi Kasei Kogyo KK) , PSZ-TZ
-3Y) was prepared and subjected to a heat treatment at a temperature of 1000 ° C. for 2 hours as a pretreatment to remove adsorbed water and volatile impurities.

Next, the spherical HAP particles, diamond particles, and PSZ powder pretreated as described above were blended so that the blending ratios were as shown in the following Table 2 in terms of weight ratio. And mixed abrasive grains having the following formulas were prepared.

[0109]

[Table 2]

The sample 6 was mixed with the high-speed stirring type mixer (O
MD-O type, K. K. OM dizer manufactured by Nara Machinery Works)
To prepare mixed abrasive grains by performing a mixing treatment (referred to as OMD treatment). The processing conditions of the high-speed stirring type mixer were set such that the rotation speed of the stirring blade was 800 rpm, the peripheral speed of the stirring blade was 2.5 m / sec, and the processing time was 5 minutes.

On the other hand, after mixing by the OMD treatment, the sample 7 was further subjected to a high-speed air current impact type powder surface reforming apparatus (Hybridizer, HYB-O) as shown in FIGS. Mold, KK Nara Machinery Works)
The diamond particles are fixed (composite) (hereinafter referred to as HYB treatment) so that the surface of the relatively large spherical HAP particles is coated with the diamond particles as fine abrasive grains by the treatment described above. A composite abrasive for Sample 7 was prepared.

Sample 8 was mixed with the above-mentioned OMD process and mixed with H
After preparing the HAP / diamond composite abrasive grains by performing the compounding of the diamond particles by YB treatment, the surface is further subjected to HYB treatment to fix the PSZ powder to form the composite abrasive grains composed of HAP / diamond / PSZ. Prepared. The processing conditions in the reformer (hybridizer) were such that the rotor rotation speed was 10,000 rpm,
The rotor peripheral speed was set to 60 m / sec, and the processing time was set to 5 minutes.

Next, the mixed abrasive grains for Sample 6 and the composite abrasive grains for Samples 7 and 8 prepared as described above were charged into a hot press (manufactured by Nems Corporation), and the mixed abrasive grains or the composite abrasive grains were mixed in a hot press apparatus.
Pressing was performed at a pressure of 0 MPa, and at the same time, heating and firing were performed at a temperature of 1150 ° C. for 15 minutes in an argon gas atmosphere, thereby preparing an abrasive made of a sintered body having a size of 6.5 × 50 × 50 mm.

FIGS. 11 to 13 are photomicrographs of the grain structure of the polished surface of the biomaterial abrasive made of the sintered body according to Samples 6 to 8, respectively, taken by a scanning laser microscope (1LM21 manufactured by Lasertech).

As shown in FIGS. 11 and 12, HAP
In the particle structure of the abrasive of Samples 6 to 7 composed of a two-component sintered body of diamond, a circular portion is HAP particles, and diamond particles as polishing abrasive grains are integrally fixed to a peripheral portion thereof. I have. By performing the hot pressing, the continuous phase of HAP is formed because the diamond particles are buried in the HAP particles.

On the other hand, as shown in FIG. 13, in the particle structure of the abrasive of Sample 8 composed of a three-component sintered body of HAP / diamond / PSZ, the circular portion is HAP particles, and the peripheral portion is diamond and diamond. A structure in which the PSZ layer is formed so as to cover is observed.

The mechanical strength of the abrasive according to Example 4 (samples 6 to 7) was about 10% lower than that of the abrasive according to Example 3 in which HAP particles manufactured by Sigma were used as a raw material of a sintered body. The value is 1.2 to 2.0 times. In particular, the mechanical strength of the abrasive according to Sample 8 using PSZ, which is high toughness ceramic particles, was about 2.5 times that of the abrasive of Example 3.
It showed a high value of up to 3.0 times, confirming that a strong sintered body was formed.

According to the respective abrasives according to Example 4 (samples 6 to 8), since the matrix sintered body and the abrasive grains are formed of a biocompatible material, the surface of a biomaterial such as an implant material is formed. When polishing is carried out with an abrasive, there is no possibility that adverse effects such as contamination of the biomaterial with impurities will occur. In addition, since HAP particles having bioactivity are contained, the HAP component can be positively attached to the surface of the biomaterial at the time of polishing, and the affinity (healing property) of the biomaterial to the living body can be increased.

Further, in the case of using composite abrasive grains in which HAP particles and diamond particles are combined by a high-speed air impact method, the bonding strength between the HAP particles and the diamond particles is high, and the abrasive grains are less likely to fall off. The surface of the object to be polished can be efficiently polished, and the life and durability as an abrasive can be greatly extended.

[0120]

As described above, according to the composite abrasive for polishing a biomaterial and the abrasive according to the present invention, since the abrasive is firmly fixed to the surface of bioceramic particles having biocompatibility, Abrasive grains are not aggregated to form coarse abrasive grains. Therefore, even if the biomaterial is polished, no coarse polishing marks are formed, and a highly accurate surface finish can be obtained. Furthermore, since abrasive grains are less likely to fall off, an abrasive material having a long life and excellent durability can be obtained.

Further, since bioceramics having bioactivity are contained as constituent materials, the bioceramic component can be positively attached to the biomaterial when the biomaterial to be polished is polished. Therefore, when the biomaterial is implanted in the living body, the affinity of the living tissue becomes good, and the fusion strength of the biomaterial can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration example of a powder surface reforming apparatus used for producing composite abrasive grains in the method of the present invention.

FIG. 2 is a side sectional view of a main body of the surface reforming apparatus shown in FIG.

FIG. 3 is a view showing a composite abrasive grain according to the present invention and a manufacturing process thereof.

FIG. 4 is a cross-sectional view showing one embodiment of the abrasive according to the present invention and showing the structure of a polishing film on which a single-layer abrasive layer is formed.

FIG. 5 is a cross-sectional view showing another embodiment of the abrasive according to the present invention, showing a structure of a polishing film on which a multilayer abrasive layer is formed.

FIG. 6 is a scanning electron micrograph showing the particle structure of spherical HAP particles.

FIG. 7 is a scanning electron micrograph showing the particle structure of abrasive grains (diamonds) used in the method of the present invention.

FIG. 8 is a scanning electron micrograph showing the particle structure of a composite abrasive prepared by the method of the present invention.

9 is a scanning electron micrograph showing the particle structure of a polishing film formed by fixing the composite abrasive grains shown in FIG. 8 to the surface of a film-like substrate.

10 is a scanning electron micrograph showing the particle structure of another example of a polishing film formed by fixing the composite abrasive grains shown in FIG. 8 to the surface of a film-like base material.

FIG. 11 is a scanning laser microscope photograph showing the particle structure of a polished surface of a biomaterial abrasive made of a sintered body of HAP / diamond mixed abrasive grains.

FIG. 12 is a scanning laser microscope photograph showing the particle structure of a polished surface of a biomaterial abrasive made of a sintered body of HAP / diamond composite abrasive grains.

FIG. 13 is a scanning laser microscope photograph showing the particle structure of a polished surface of a biomaterial abrasive made of a sintered body of HAP / diamond / PSZ composite abrasive.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Powder surface reforming apparatus (hybridizer) 2 Main body casing 3 Rear cover 4 Front cover 5 Rotor 6 Impact pin 7 Rotating shaft 8 Impact ring 9 Open / close valve 10 Valve shaft 11 Actuator 12 Circulation circuit 12a Inlet 12b Outlet 13 Raw material hopper 14 Raw material supply chute 15 Open / close valve 16 Impact chamber 17 Modified powder discharge pipe 18 Back collector 19 Preprocessor 20 Raw material measuring feeder 21 Jacket 30 Biocompatible bioceramic particles (base particles) 31 Abrasive abrasive particles (child particles) 32) base material (film-like base material) 33 binder (binder resin) 34a, 34b abrasive (polishing film) 40 composite abrasive

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Kenichi Watanabe 1-13-11-402 Higashi Kojiya, Ota-ku, Tokyo (72) Inventor Kenji Ono 2-38-7 Highland, Yokosuka City, Kanagawa Prefecture (72) Inventor Koishi Shinjun 2-27-5-403 Unomori, Sagamihara City, Kanagawa Prefecture

Claims (16)

[Claims] 1. A biomaterial comprising a biocompatible ceramic material having a particle size smaller than that of the bioceramic particles and a biocompatible polishing abrasive fixed to the surface of the biocompatible ceramic particles. Composite abrasive for polishing. 2. The method according to claim 1, wherein the bioceramic particles having biocompatibility are bioactive hydroxyapatite (HA).
2. The composition according to claim 1, wherein the composition comprises at least one selected from the group consisting of P), tricalcium phosphate (TCP), living glass, crystallized glass, and bioinert alumina, zirconia, calcium aluminate, and aluminosilicate. The composite abrasive for polishing a biomaterial according to the above. 3. The composite abrasive for biomaterial polishing according to claim 1, wherein the average particle size of the biocompatible bioceramic particles is at least 5 times the average particle size of the polishing abrasive particles. 4. The polishing material for biomaterials according to claim 1, wherein the biocompatible abrasive grains are at least one selected from diamond, alumina, zirconia, silicon nitride and silicon carbide. Composite abrasive. 5. The method according to claim 1, wherein the surface of the biocompatible ceramic particles is fixed to the surface of the bioceramic particles by a high-speed air impact method so as to cover the surface of the bioceramic particles. Of producing composite abrasive grains for polishing biomaterials. 6. A composite abrasive grain comprising a biocompatible ceramic particle having a particle size smaller than that of the bioceramic particle and a biocompatible abrasive grain fixed thereto is formed on the surface of the biocompatible ceramic particle. A biomaterial abrasive material characterized by being elastically supported and fixed to a subject via a binder. 7. The biomaterial abrasive according to claim 6, wherein the substrate is a film-like substrate made of at least one selected from polyethylene terephthalate (PET), polyimide, and polycarbonate. 8. The biomaterial abrasive according to claim 6, wherein the substrate is a disk-shaped substrate made of at least one selected from paper, hard rubber, soft synthetic resin and metal. 9. The polishing of biomaterial according to claim 6, wherein the binder comprises at least one selected from a synthetic polymer such as synthetic rubber and synthetic resin, a chemically treated biomaterial and a natural polymer. Wood. 10. A biomaterial abrasive comprising a matrix sintered body composed of biocompatible bioceramic particles and biocompatible abrasive grains dispersed therein. 11. A sintered body of composite abrasive grains in which bioabrasive particles having a smaller particle diameter and biocompatibility are fixed to the surface of bioceramic bioceramic particles to form a composite. A biological material abrasive comprising: 12. The biomaterial abrasive according to claim 11, wherein the abrasive has an average particle size of 10 μm or less. 13. The biomaterial abrasive according to claim 11, wherein high-toughness ceramic particles having a smaller particle diameter than the abrasive grains are further fixed on the surface of the composite abrasive grains to form a composite. 14. The biomaterial abrasive according to claim 13, wherein the high toughness ceramic is at least one of partially stabilized zirconia (PSZ) and alumina. 15. A composite abrasive comprising fixing the abrasive grains to the surface of the bioceramic particles by a high-speed air impact method so that the surface of the biocompatible bioceramic particles is coated with the biocompatible abrasive grains. A method for producing a biomaterial abrasive, comprising preparing a composite abrasive grain under pressure, and sintering the compact in a non-oxidizing atmosphere. 16. The method according to claim 15, wherein high-toughness ceramic particles having a smaller particle size than the polishing abrasive grains are further fixed to the surface of the composite abrasive grains using a high-speed air current impact method. A method for producing a biomaterial abrasive.