KR20200083731A - Drug releasing carbon fiber stent and manufacturing method for the same - Google Patents

Abstract

The present invention relates to a stent made of a carbon fiber material having size-controlled pores on the surface thereof so as to dip a drug for release. The stent has a hollow tubular shape, and a mesh structure body is composed of carbon fibers having pores formed on the surface thereof. The size of the pores is adjusted on the basis of one among the type, amount, and release speed of a drug to be dipped. According to the stent of the present invention, carbon fibers having multiple pores formed on the surface thereof are used as a basic material, and thus the size of pores is adjusted. Accordingly, a drug release stent capable of adjusting the release speed of a drug dipped in pores on the surface thereof can be provided. In addition, the size of pores is controlled, so that the dipping amount of a drug can be maximized and the drug release speed can be controlled.

Description

DRUG RELEASING CARBON FIBER STENT AND MANUFACTURING METHOD FOR THE SAME

The present invention relates to a stent used in a human body and a method of manufacturing the same, and more particularly, to a stent made of a carbon fiber material capable of supporting and releasing a drug and a method of manufacturing the same.

With the recent development of medical technology, the importance of the bio-replacement industry, which is used by being injected into the human body for treatment or bio-replacement, is emerging.

The ideal stent is proposed to have the following characteristics. It should be able to be physically attached to the balloon catheter attached to the guide wire, and should be maintained in an expanded state due to excellent expandability, and should not be restored to its original state after expansion, and elastic arterial vessels It has been reported that it should be flexible enough to pass through, nuclear magnetic resonance image (MRI) should be detected, it must be a material having thrombosis resistance to red blood cells and easy drug delivery. (G. Mani, Biomaterials 28 (2007) 1689)

Among typical biomaterials, stents are typical biomaterials for treatment. Materials constituting such bio-replacement products include polymers and metal materials such as stainless steel, Ti-based alloys, and Co-based alloys, and ceramics. The basic biomedical conditions of these biomaterials are excellent in biocompatibility, should not be toxic to the human body, and are required to improve functionality for smooth operation in vivo. All of these conditions are highly dependent on the surface properties of the bio-insertable material, so it can be said that the surface modification technology is a key technology to measure the success of the bio-material.

Interventional procedures using vascular stents for the treatment of obstructive vascular disease are widely used around the world because they are simpler and safer than surgical procedures, do not require general anesthesia, and have a high success rate. As a blood vessel stent, a bare stent without coating is generally used. These stents are inserted into the inside of blood vessels, and the surface is directly in contact with the inner wall of the blood vessel. In the case of metal stents, metal components may be released into the blood vessels, and blood clots may be generated in the blood, causing problems such as adsorption on the blood vessel walls. It may happen.

Therefore, in order to solve this problem, the biocompatibility surface treatment of the stent surface is very important. Recently, a method of coating the surface of a stent with materials having a function having properties that are harmless to the human body has been used. Carbon, silicon carbide, titanium nitride, and tantalum are examples of the surface coating material of the stent.

On the other hand, in recent years, efforts to apply a stent capable of carrying a drug so that the drug is released from the stent installed in the human body have been continued, and a technique for forming pores for drug loading on the stent surface has been developed. The technology selects a method of forming a covalent bond with the surface through a chemical reaction or introducing a drug into a biopolymer to coat the stent surface in order to introduce the drug to the stent surface. This method is difficult to control the rate of drug release and the amount of drug that can be supported is limited.

Through the reaction, however, the manufacturing cost is high or the process is high, such as processing the surface with a high-cost femtosecond laser (Registration No. 10-1786020) or coating the polymer film with pores on the surface of the stent (Republic of Korea 10-2017-0037780). There are complex disadvantages.

Republic of Korea Registered Patent 10-1786020 Republic of Korea Patent Publication 10-2017-0037780

The present invention is intended to solve the problems of the prior art described above, and has an object to provide a stent made of a carbon fiber material capable of releasing a supported drug and a method of manufacturing the same.

The drug-releasing carbon fiber stent according to the present invention for achieving the above object is a hollow tube-shaped body composed of carbon fibers having pores formed on the surface of the mesh structure, and the type and amount and release rate of the drug to be supported. It is characterized in that the size of the pores is adjusted based on one of them.

At this time, the method of adjusting the size of the pores is performed in a method of adjusting the ratio of mixing the pitch to 0 to 100 parts by weight with respect to 100 parts by weight of PAN in constructing the precursor material spinning solution for producing carbon fibers.

The stent has a hollow tube shape, and the body has a structure in which a gap is formed in a mesh structure. The present invention is characterized in that such a stent is composed of carbon fibers with pores formed on the surface. The mesh structure is a structure that is woven sparingly so that there is an empty space like a net, and is different from a simple arrangement of yarns in that it is a structure in which carbon fibers are woven together, such as cloth, and can maintain its shape as it is. The present invention has a property of preventing blood clots by itself without the need to coat the carbon material on the stent surface of the metal material by applying a mesh structure woven from a carbon fiber material having pores formed therein, and has a property of preventing blood clots by itself It can be released by supporting. In addition, due to the characteristics of the carbon fiber material, it has excellent mechanical properties. Furthermore, it is possible to improve the drug carrying performance by introducing a functional group on the surface.

The pores formed on the surface of the carbon material show a large specific surface area of 2500 m ² /g It effectively carries a drug that is suitable for the size of the pores, and if the shape and size of the molecule of the drug is suitable for the shape and size of the pores, it can carry the maximum drug and the release rate is the slowest (Kaneko, Katsumi). , et al. Nature Materials (2017), 16(12) 1225+)

Therefore, by controlling the size of the pores formed on the surface of the carbon fibers constituting the stent, a difference occurs in the type and amount of the drug supported and the release rate.

The present invention is characterized in that different sizes of pores formed on the surface of the carbon fiber are controlled by adjusting the proportion of substances constituting the precursor substance spinning solution according to the type, amount, and release rate of the supported drug.

The carbon fiber constituting the stent may be a carbon fiber thread or a carbon fiber strand.

In this specification, the steps of carbon fiber were used as follows.

Carbon fiber filament refers to the smallest unit of carbon fiber represented by short fibers, carbon fiber yarn refers to a long yarn composed of carbon fiber filaments, and carbon fiber strand refers to a string formed by twisting a plurality of carbon fiber yarns do.

Depending on the size and use of the stent, a carbon fiber thread or a carbon fiber strand can be selectively used.

The carbon fibers constituting the mesh may be fixed to each other so that the stent maintains the mesh structure and maintains a constant space therein even in the contraction pressure of the blood vessel.

A method of manufacturing a drug-release carbon fiber stent according to another aspect of the present invention comprises: a spinning step of forming a precursor short fiber by spinning a spinning solution containing PAN as a precursor material; Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers; An activation step of forming pores on the surface by a surface activation process for the carbon fiber filaments; Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; And a stent construction step of manufacturing a stent by weaving a carbon fiber yarn into a hollow tubular mesh structure, and by adjusting the ratio of mixing the pitch to 0 to 100 parts by weight with respect to 100 parts by weight of PAN in the spinning step, the It is characterized by controlling the size of the pores formed in the activation step.

A method of manufacturing a drug-release carbon fiber stent according to another aspect of the present invention comprises: a spinning step of forming a precursor short fiber by spinning a spinning solution containing PAN as a precursor material; Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers; An activation step of forming pores on the surface by a surface activation process for the carbon fiber filaments; Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; And a stent construction step of manufacturing a stent by weaving a carbon fiber yarn into a hollow tubular mesh structure, and by adjusting the ratio of mixing the pitch to 0 to 100 parts by weight with respect to 100 parts by weight of PAN in the spinning step, the It is characterized by controlling the size of the pores formed in the activation step.

A method of manufacturing a drug-release carbon fiber stent according to another aspect of the present invention comprises: a spinning step of forming a precursor short fiber by spinning a spinning solution containing PAN as a precursor material; Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers; Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; An activation step of forming pores on the surface by a surface activation process for the carbon fiber yarns; And a stent configuration step of manufacturing a stent by weaving a carbon fiber yarn into a hollow tubular mesh structure, and by adjusting the ratio of mixing the pitch from 0 to 100 parts by weight with respect to 100 parts by weight of PAN in the spinning step, the It is characterized by controlling the size of the pores formed in the activation step.

In the stent construction step, when the carbon fiber fixing process for fixing the position of the carbon fiber yarns constituting the mesh structure is performed by vapor phase deposition with hydrocarbon, the pores are blocked in the fixing process, and thus activated after the fixing process is performed. It is preferred to perform the steps.

After the carbon fiber yarn forming step, the carbon fiber strand is further twisted to form a carbon fiber strand by twisting the carbon fiber yarn, and in the stent construction step, the carbon fiber strand is woven into a hollow tubular mesh structure to produce a stent. May be

When TEOS is added to the spinning solution, the pore size is controlled on the surface of the carbon fiber and the specific surface area is also improved.

The activation step may be performed by heat treatment in one of an atmosphere including water vapor and carbon dioxide and an atmosphere including both water vapor and carbon dioxide.

The activation step can be performed by surface treatment with a chemical.

The stent construction step of constituting the stent by weaving the carbon fiber into a mesh structure includes: a step of forming a fabric in which a fabric in the form of a knitted fabric or a fabric is woven using insert fibers for forming a gap between the carbon fiber yarn and the carbon fiber yarn; And removing the inserted fiber to remove the inserted fiber to form a carbon fiber yarn in a mesh structure by leaving only the carbon fiber yarn, and in the fabric forming step, when weaving a knitted fabric or a fabric type, weave the fabric into a hollow tube shape. , In the step of removing the inserted fiber, the inserted fiber is removed, it may be characterized in that the hollow fiber has a tubular shape and the body of the mesh structure is made of carbon fiber stent.

The second form of the stent constituting step includes: a step of forming a fabric in which a knitted or woven fabric is woven using an insert fiber for forming a gap between the carbon fiber yarn and the carbon fiber yarn; A tube structure forming step of fixing the knitted or woven fabric in a hollow tube shape; And removing the inserted fiber to leave the carbon fiber thread, thereby removing the inserted fiber to form the carbon fiber thread in a mesh structure, and in the removing the inserted fiber, by removing the inserted fiber while fixing the cloth in the shape of a hollow tube , It may be characterized in that the hollow tube-like and mesh-structured body is composed of carbon fiber and a carbon fiber stent is manufactured.

The third form of the stent construction step includes: a fabric forming step of weaving a fabric in a knitted or woven form using insert fibers for forming a gap between the carbon fiber yarn and the carbon fiber yarn; Removing the inserted fiber to remove the inserted fiber to form a carbon fiber thread in a mesh structure by leaving only the carbon fiber thread; And a tube structure forming step of fixing the mesh structure into a hollow tube shape, and in the step of forming the tube structure, by fixing the mesh structure into a tube shape, the hollow tube shape and the body of the mesh structure composed of carbon fibers. It may be characterized by manufacturing a carbon fiber stent.

In the present invention, the process of forming the stent of the mesh structure using the carbon fiber is manufactured by weaving the carbon fiber with a knitted or woven fabric, but inserting fibers together to form a gap between the carbon fibers to form a mesh structure After weaving the fabric, the method of removing the inserted fibers was applied.

At this time, the first stent construction method consisted of weaving the fabric itself into a hollow three-dimensional tubular shape, and the second and third stent construction methods woven the two-dimensional flat fabric, rolled it, and rolled it. The tube shape was constructed. In addition, the second stent construction method is to remove the insertion fiber after constructing the hollow tube shape in a cloth state including the insertion fiber, while the third stent construction method is to remove the insertion fiber first to produce a carbon fiber mesh structure and then to hollow. The tube shape was constructed.

In the manufacturing method of the present invention, in the step of forming the fabric, the spacing between the carbon fibers constituting the mesh structure may be adjusted by adjusting the thickness or the number of inserts of the fibers interwoven with the carbon fibers.

The carbon fiber fixing step for fixing the position of the carbon fibers constituting the mesh structure may be additionally performed so that the stent maintains the mesh structure even in the contraction pressure of the blood vessel to maintain a constant space therein. The carbon fiber fixing step may be performed after the fabric forming step of weaving the cloth together with the insert fiber, or may be performed after the insert fiber removing step of removing the insert fiber to leave only the carbon fiber. Furthermore, in the step of fixing the carbon fiber, a method of fixing the stent to maintain the mesh structure even when the blood pressure is contracted by maintaining the spacing of the carbon fibers may be applied without limitation.

A method of manufacturing a drug-release carbon fiber stent according to another aspect of the present invention comprises: a spinning step of forming a precursor short fiber by spinning a spinning solution containing PAN as a precursor material; Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers; Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; And a stent construction step of manufacturing a stent by weaving the carbon fiber yarn into a hollow tubular mesh structure, and in the stent construction step, using inserted fibers to form a gap between the carbon fiber yarn and the carbon fiber yarn. After weaving a knitted or woven fabric, the process of removing the inserted fiber and removing the inserted fiber and the surface activation process of forming pores on the surface of the carbon fiber thread are simultaneously performed, and the pitch of 100 parts by weight of PAN in the spinning step is performed. It is characterized by controlling the size of the pores formed in the activation step by adjusting the ratio of mixing to 0 to 100 parts by weight.

The stent of the present invention configured as described above, by using a carbon fiber having a large number of pores formed on the surface as a base material to prepare a stent having a pore size controlled, it is possible to control the release rate of the drug carried on the pores of the surface. It has the effect of providing a drug release stent.

In addition, by manufacturing a stent using carbon fiber as a base material, it has a property of preventing thrombus, and has excellent mechanical properties by itself, and has an effect of easily introducing a functional group to the surface.

Furthermore, the manufacturing method of the present invention can easily manufacture a stent that maintains a constant space therein by maintaining the mesh structure of the stent even when the blood pressure is contracted, and it is easy to control the spacing between carbon fibers. .

1 is a view showing a carbon fiber stent according to an embodiment of the present invention.
2 is a flow chart showing a process for manufacturing a drug-release carbon fiber stent according to an embodiment of the present invention.
3 is a flow chart showing a process for manufacturing a drug-release carbon fiber stent according to another embodiment of the present invention.
4 is a flow chart showing a process for manufacturing a drug-release carbon fiber stent according to another embodiment of the present invention.
5 shows a state in which a cloth is formed using carbon fibers and insert fibers according to an embodiment of the present invention.
6 shows a state in which a cloth is formed using a plurality of insert fibers between carbon fibers according to an embodiment of the present invention.
7 is a flow chart showing the manufacturing procedure of the carbon fiber stent according to the first method of the present invention.
8 is a view showing a state of weaving the fabric in a three-dimensional hollow tube shape.
9 is a flow chart showing the manufacturing procedure of the carbon fiber stent according to the second method of the present invention.
10 is a flow chart showing a manufacturing procedure of the carbon fiber stent according to the third method of the present invention.

An embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing a carbon fiber stent according to an embodiment of the present invention.

Carbon fiber stent 100 of this embodiment is characterized in that the body of the mesh structure made of carbon fiber material is a hollow tube shape.

The stent is a typical use that is injected into a blood vessel to prevent clogging of blood vessels, etc. In addition, it is manufactured to be inserted into various parts of the human body, and for this purpose, it has a hollow tube shape, and the stent has a mesh structure despite the contraction pressure of the blood vessel. To maintain a constant space inside. The carbon fiber stent 100 of this embodiment has a shape reflecting the characteristics of the stent, and is characterized in that the material is composed of carbon fibers having pores formed on the surface.

Carbon fiber is a fibrous material composed only of carbon, and is excellent in mechanical strength and heat resistance, and thus is used as a composite material for mixing with various materials to form a composite material. In the present invention, carbon fibers were used as a basic material constituting the stent, and the carbon fibers were interwoven to make the mesh structure by coarsely woven so that there was an empty space such as a net. It is different from the one. In the present invention, a carbon fiber stent may be manufactured by using a carbon fiber yarn, which is a long yarn composed of carbon fiber filaments, which are carbon fibers of the smallest unit represented by a short fiber, or carbon in a string form formed by twisting a plurality of carbon fiber yarns Carbon fiber stents can also be produced using fiber strands.

At this time, carbon fiber filaments are produced by firing organic polymer fibers at high temperature, and are currently produced from acrylic (polyacrylonitrile, PAN) fibers, pitch fibers, and liquid crystal pitch fibers. In the carbon fiber stent of the present invention, carbon fibers made of various mentioned raw materials are woven into a mesh, and pores are formed on the surface of the carbon fibers through surface activation.

In particular, in the present invention, in order to control the size of the pores formed on the surface of the carbon fiber, the mixing ratio of the PAN and the pitch was adjusted in the process of preparing the precursor short fibers by mixing the PAN and the pitch. Specifically, the size of the pores formed on the surface of the carbon fiber obtained from the precursor fiber made of only PAN without using a pitch is about 1.3 nm, and when the pitch is included at a weight ratio of 50%, the pore size is about 0.6 nm to be. However, if the pitch content exceeds 50%, uniform fibers cannot be formed. Therefore, the size of the pores can be controlled by using PAN as a raw material, but by adjusting the pitch in the range of 0-50% by weight ratio. After all, by adjusting the pore size, it is possible to control the type and amount of the drug to be supported or the release rate, and, conversely, the carbon fiber having the required pore size based on the type and amount of the drug to be supported and the release rate. Stents can also be prepared.

At this time, in the process of constructing the spinning solution, DMF (Dimethylformamide), a solvent of PAN, and THF (Tetrahydrofuran), a solvent of pitch, were mixed and used.

Meanwhile, in the present invention, a tetraethly orthosilicate (TEOS) may be mixed with a precursor material for the purpose of forming surface pores for supporting a drug to form a spinning solution.

The precursor short fibers produced by spinning the spinning solution are made of carbon fibers by a carbonization process, and a stabilization process may be performed on the precursor short fibers to smoothly perform the carbonization process. The stabilization process is a step of stabilizing the electrospun precursor short fibers by hot air. The stabilization process is carried out in the range of 200 ~ 300 ℃, it is preferably carried out at about 280 ℃.

When the surface activation process is performed on the carbon fiber filament prepared by carbonizing the precursor short fibers, a plurality of pores may be formed on the surface. At this time, the surface activation process may perform a physical activation process of heat treatment in a range of 700 to 900°C in an atmosphere of water vapor or carbon dioxide or a mixture thereof. In addition, a chemical activation process using KOH, NaOH, CaCO ₃ , Na ₂ CO _3, etc., which are chemicals for forming pores on the surface of the carbon fiber, may be performed.

The carbon fiber filaments produced through this manufacturing process are formed with fine pores on the surface, and as described above, a plurality of pores of which size is controlled is formed by a method of controlling the mixing ratio of PAN and pitch.

The carbon fiber yarn formed by collecting carbon fiber filaments having pores formed on the surface through this process may be woven into a mesh structure to form a drug-release carbon fiber stent, or a string of carbon fiber strands formed by twisting a plurality of carbon fiber yarns It is also possible to compose a drug-release carbon fiber stent by weaving it into a mesh structure.

The flowchart for preparing the drug-release carbon fiber stent through the above process is shown in FIG. 2. The method of weaving the carbon fiber yarn or carbon fiber strand into a mesh structure will be described in detail later.

On the other hand, unlike the case in which the carbon fiber filament and the carbon fiber strand are first formed after the pores are first formed on the surface in FIG. 2, the order of performing the surface activation process is performed after the carbon fiber yarn is formed or the carbon fiber strand is It can also be done after configuration.

3 is a flow chart showing a process for manufacturing a drug-release carbon fiber stent according to another embodiment of the present invention.

The left side of FIG. 3 is a case where a carbon fiber stent is prepared after forming a pore by performing surface activation after forming a carbon fiber filament as a carbon fiber thread. The right side of FIG. 3 is a case where a carbon fiber stent is produced after forming a pore by performing surface activation after forming a carbon fiber filament with a carbon fiber thread and a carbon fiber strand.

Furthermore, the order of performing the surface activation process may be performed after the carbon fiber stent is formed, and FIG. 4 is a flow chart showing a process of manufacturing the drug-release carbon fiber stent according to another embodiment of the present invention. .

Depending on the method of weaving the carbon fiber into a mesh structure, the carbon fiber may maintain the mesh structure without a separate fixing process, but in some cases, a fixing process for fixing the carbon fiber after forming the mesh structure must be performed. , In the fixing process, a method of impregnating carbon by vapor deposition is mainly used. At this time, when pores are previously formed on the surface of the carbon fiber, a problem occurs in that the pores are clogged in the vapor deposition process, so it is preferable to perform the activation process after forming the carbon fiber stent.

Hereinafter, a method of manufacturing a drug-release carbon fiber stent by weaving a carbon fiber yarn or carbon fiber strand with pores formed on the surface in a mesh structure will be described in detail. Hereinafter, the carbon fiber yarn and the carbon fiber strand are grouped and expressed as'carbon fiber'.

The drug-release carbon fiber stent 100 shown in FIG. 1 is a mesh structure in the form of a woven fabric in which carbon fiber warp (slanting) 110 and carbon fiber weft (weft) 120 cross each other downward-upward. to be. The form in which the carbon fiber is woven into a mesh structure is not only possible in the fabric structure of FIG. 1, but a knitting structure in which a knitting form is formed by connecting a loop (nose, loop) to the front, back, left, and right is also possible. In addition, various concrete structures constituting fabrics and knitted fabrics can be applied.

Although it is not impossible to weave the immediately spaced mesh structure using carbon fibers with pores on the surface, it is quite complicated to directly weave the spaced mesh structure because the size of the stent is small. Therefore, in the present invention, the following method was applied to prepare a drug-release carbon fiber stent composed of carbon fibers having a hollow tube shape and a body having pores formed on its surface.

In the method of manufacturing the drug-release carbon fiber stent according to the present invention, a method of weaving carbon fibers like a general cloth not forming a gap was applied, rather than weaving carbon fibers to directly form gaps. At this time, after the fabric was woven by using the inserted fibers together to adjust the spacing between the carbon fibers together with the carbon fibers, only the inserted fibers were removed to form a mesh structure in which the gaps between the carbon fibers were formed.

Accordingly, the method of manufacturing a carbon fiber stent according to the present invention includes the step of forming the fabric and knitting the fabric in the form of a knitted or woven fabric using insert fibers to form a gap between the carbon fibers and the carbon fibers, and removing the insert fibers to remove carbon. It is characterized in that it is performed by separating the insertion fiber removal step of forming the carbon fiber into a mesh structure by leaving only the fibers.

5 shows a state in which a cloth is formed using carbon fibers and insert fibers according to an embodiment of the present invention.

The carbon fiber warp yarn 110 and the inserted fiber warp yarn 210 are alternately positioned without spacing, and the carbon fiber weft yarn 120 and the inserted fiber weft yarn 220 are alternately positioned without spacing, and the warp yarns 110 and 210 ) And weft (120, 220) cross each other from top to bottom is a woven fabric without spacing.

As described above, when the carbon fibers 110 and 120 and the insertion fibers 210 and 220 are woven together, the insertion fibers 210 and 220 are removed to form a mesh structure having a gap formed between the carbon fibers. At this time, in order to widen the gap between the carbon fibers, a method of removing the inserted fibers after weaving the fabric by constructing a thicker thickness of the inserted fibers may be applied.

As another method for widening the gap between the carbon fibers, there is a method of weaving the fabric so that a plurality of interposed fibers are positioned between the carbon fibers, and this is illustrated in FIG. 6.

In FIG. 6, the case where the fabric is woven so that the two inserted fiber warp 210 is located between the carbon fiber warp 110 and the two inserted fiber weft 220 is located between the carbon fiber weft 120 is also shown. Did. At this time, when the inserted fibers 210 and 220 are removed, a mesh structure having a larger gap between the carbon fibers in FIG. 2 may be formed. As such, it is possible to control the spacing between the carbon fibers by adjusting the number of inserted fibers.

As a method of removing the inserted fiber, various methods may be applied depending on the characteristics of the inserted fiber. For example, if the insert fiber is a material that can be completely removed in a temperature range that does not affect the carbon fiber, only the insert fiber can be removed by applying heat. In addition, it may be possible to remove only the inserted fiber through a chemical treatment.

At this time, in order to prevent the carbon fiber from moving into an empty space after the inserted fiber is removed, a carbon fiber fixing step of fixing the position of the carbon fiber may be additionally performed. The carbon fiber fixing step may be performed after the fabric forming step of weaving the cloth together with the insert fiber, or may be performed after the insert fiber removing step of removing the insert fiber to leave only the carbon fiber. Further, in the step of fixing the carbon fiber, the method of fixing the fiber to maintain the mesh structure by maintaining the spacing of the carbon fibers may be applied without limitation, such as coating the outside.

As described above, since a method of applying heat and a chemical can be applied in the process of removing the inserted fiber, the process of removing the inserted fiber and the surface activation process described above can be configured together. . Since the physical activation process is performed in the range of 700 to 900°C, when insert fibers of a material that can be removed in this temperature range are used, the insertion fibers can be removed while performing the physical activation process. In addition, when insert fibers of a material that is decomposed by chemicals used in chemical activation processes such as KOH, NaOH, CaCO ₃ , and Na ₂ CO ₃ can be removed while performing the chemical activation process.

On the other hand, although it was confirmed that the carbon fiber can be squeezed into a mesh structure by removing the inserted fiber after forming the fabric using the inserted fiber, the stent should be basically manufactured in a hollow tube shape.

To this end, in the method of manufacturing a carbon fiber stent of the present invention, a step of forming a tube structure is required to form a hollow tube shape, and three manufacturing methods can be configured depending on which step is performed to form the tube structure. .

First, as shown in FIG. 7, in the process of forming the fabric using the carbon fiber and the inserted fiber together, the method is to knit the fabric into a hollow tube shape in three dimensions.

8 is a view showing a state of weaving the fabric in a three-dimensional hollow tube shape.

As shown, it is possible to weave in the shape of a hollow tube rather than a two-dimensional planar shape in the process of weaving the warp and weft yarns to manufacture the fabric. When the fabric is woven into a hollow tube shape, there is no need to separately perform a process of forming a hollow tube structure, and the carbon fiber stent can be directly prepared by removing the inserted fiber to form a mesh structure.

In the second method, as shown in FIG. 9, after weaving a general two-dimensional fabric using carbon fibers and insert fibers together, the fabric is rolled round to form a hollow tube structure. Carbon fiber stents can be manufactured by forming a hollow tube-like cloth to be fixed by hooking or bundling the ends of each other, and then removing the inserted fibers to form a mesh structure.

In the third method, as shown in FIG. 10, after weaving a general two-dimensional fabric by using carbon fibers and insert fibers together, the insert fibers are removed to form a mesh structure, thereby first producing a two-dimensional carbon fiber mesh structure. do. In addition, the carbon fiber stent can be manufactured by forming a hollow tube structure by fixing the ends of the carbon fiber mesh structure by rolling or binding each other.

On the other hand, the carbon fiber fixing step of fixing the position of the carbon fibers constituting the mesh structure may be additionally performed so that the stent maintains a mesh structure and maintains a constant space therein even in the contraction pressure of the blood vessel.

The method of fixing the position of the carbon fiber can be applied without limitation without detracting from the features of the present invention. For example, it is also possible to fix the overlapping portion of the carbon fibers by sticking the carbon using a gas, or to reinforce the overlapping portion of the carbon fiber using a resin.

Further, the step of fixing the carbon fiber may be performed after the step of forming the fabric weaving with the insert fiber, or may be performed after the step of removing the insert fiber leaving only the carbon fiber by removing the insert fiber.

The present invention has been described through preferred embodiments, but the above-described embodiments are merely illustrative of the technical spirit of the present invention, and various changes are possible within the scope of the present invention. Anyone with ordinary knowledge will understand. Therefore, the protection scope of the present invention should be interpreted by the matters described in the claims, not by specific embodiments, and all technical ideas within the equivalent range should be interpreted as being included in the scope of the present invention.

100: carbon fiber stent
110: carbon fiber warp
120: carbon fiber weft
210: insert fiber warp
220: inserted fiber weft

Claims (18)

The hollow tube-shaped body of the mesh structure is composed of carbon fibers with pores formed on the surface.
Characterized in that the pore size is adjusted based on one of the type, amount, and release rate of the drug to be supported, and the drug-release carbon fiber stent.
The method according to claim 1,
A drug-release carbon fiber stent, characterized in that the carbon fiber is a carbon fiber thread.
The method according to claim 1,
A drug-release carbon fiber stent, characterized in that the carbon fiber is a carbon fiber strand.
The method according to claim 1,
In constructing the precursor material spinning solution for producing carbon fiber, the size of pores is controlled by adjusting the ratio of mixing the pitch to 0 to 100 parts by weight with respect to 100 parts by weight of PAN. Stent.
A spinning step of spinning a spinning solution containing PAN as a precursor material to form precursor short fibers;
Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers;
An activation step of forming pores on the surface by a surface activation process for the carbon fiber filaments;
Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; And
It includes a stent construction step of manufacturing a stent by weaving a carbon fiber thread into a hollow tubular mesh structure,
Method of manufacturing a drug-release carbon fiber stent, characterized in that by controlling the ratio of mixing the pitch to 0 to 100 parts by weight relative to 100 parts by weight of PAN in the spinning step, the size of the pores formed in the activation step.
A spinning step of spinning a spinning solution containing PAN as a precursor material to form precursor short fibers;
Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers;
Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn;
An activation step of forming pores on the surface by a surface activation process for the carbon fiber yarns; And
It includes a stent construction step of manufacturing a stent by weaving a carbon fiber yarn into a hollow tubular mesh structure,
Method of manufacturing a drug-release carbon fiber stent, characterized in that by controlling the ratio of mixing the pitch to 0 to 100 parts by weight relative to 100 parts by weight of PAN in the spinning step, the size of the pores formed in the activation step.
A spinning step of spinning a spinning solution containing PAN as a precursor material to form precursor short fibers;
Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers;
Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn;
Stent construction step of manufacturing a stent by weaving a carbon fiber yarn in a hollow tubular mesh structure; And
And an activation step of forming pores on the surface by a surface activation process for the stent made of the carbon fiber yarn,
Method of manufacturing a drug-release carbon fiber stent, characterized in that by controlling the ratio of mixing the pitch to 0 to 100 parts by weight relative to 100 parts by weight of PAN in the spinning step, the size of the pores formed in the activation step.
The method according to claim 7,
In the stent configuration step, the method of manufacturing a drug-release carbon fiber stent, characterized in that performing a carbon fiber fixing process for fixing the position of the carbon fiber yarns constituting the mesh structure.
The method according to claim 8,
Method of manufacturing a drug-release carbon fiber stent, characterized in that the carbon fiber fixing process is carried out by vapor phase deposition with hydrocarbons.
The method according to any one of claims 5 to 7,
After the carbon fiber yarn forming step, further performing a carbon fiber strand forming step of twisting the carbon fiber yarn to form a carbon fiber strand,
In the step of constructing the stent, a method for manufacturing a drug-release carbon fiber stent, characterized in that the stent is produced by squeezing the carbon fiber strand into a hollow tubular mesh structure.
The method according to any one of claims 5 to 7,
Method for producing a drug-release carbon fiber stent, characterized in that TEOS is added to the spinning solution.
The method according to any one of claims 5 to 7,
The activation step, the method of producing a drug-release carbon fiber stent, characterized in that is performed by heat treatment in one of the atmosphere containing both water vapor and carbon dioxide and the atmosphere containing water vapor and carbon dioxide.
The method according to any one of claims 5 to 7,
The activation step, the method of manufacturing a drug-release carbon fiber stent, characterized in that is performed by surface treatment with a chemical.
The method according to any one of claims 5 to 7,
The stent configuration step,
A fabric forming step of weaving the fabric in the form of a knitted fabric or a fabric using insert fibers for forming a gap between the carbon fiber yarn and the carbon fiber yarn; And
And removing the inserted fibers to leave only the carbon fiber threads, thereby removing the inserted fibers to form the carbon fiber threads into a mesh structure.
In the fabric forming step, when weaving a knitted or woven fabric, weave the fabric in a hollow tube shape,
In the step of removing the inserted fiber, the method of manufacturing a drug-release carbon fiber stent, characterized in that the carbon fiber stent is made of a hollow tubular and mesh-structured body by removing the inserted fiber.
The method according to any one of claims 5 to 7,
The stent configuration step,
A fabric forming step of weaving the fabric in the form of a knitted fabric or a fabric using insert fibers for forming a gap between the carbon fiber yarn and the carbon fiber yarn;
A tube structure forming step of fixing the knitted or woven fabric in a hollow tube shape; And
And removing the inserted fibers to leave only the carbon fiber threads, thereby removing the inserted fibers to form the carbon fiber threads into a mesh structure.
In the step of removing the inserted fiber, by removing the inserted fiber in a state where the fabric is fixed in the shape of a hollow tube, the drug-release carbon characterized in that the hollow tube-shaped body of the mesh structure is composed of carbon fibers and a carbon fiber stent is produced. Fiber stent manufacturing method.
The method according to any one of claims 5 to 7,
The stent configuration step,
A fabric forming step of weaving the fabric in the form of a knitted fabric or a fabric using insert fibers for forming a gap between the carbon fiber yarn and the carbon fiber yarn;
Removing the inserted fiber to remove the inserted fiber to form a carbon fiber thread in a mesh structure by leaving only the carbon fiber thread; And
And forming a tube structure for fixing the mesh structure to a hollow tube shape,
In the step of forming the tube structure, by fixing the mesh structure in a tubular shape, the method of manufacturing a drug-release carbon fiber stent, characterized in that to produce a carbon fiber stent of a hollow tube shape and the body of the mesh structure composed of carbon fibers.
The method according to claim 14,
In the step of forming the fabric, the method for manufacturing a drug-release carbon fiber stent, characterized in that the spacing between the carbon fiber yarns constituting the mesh structure is controlled by adjusting the thickness or the number of insertion fibers for weaving the fabric with the carbon fiber yarns.
A spinning step of spinning a spinning solution containing PAN as a precursor material to form precursor short fibers;
Carbonization step of forming a carbon fiber filament by the carbonization process for the precursor short fibers;
Forming a carbon fiber yarn by collecting carbon fiber filaments to form a carbon fiber yarn; And
It comprises a stent configuration step of manufacturing a stent by weaving a carbon fiber yarn in a hollow pipe-shaped mesh structure,
In the step of constructing the stent, the process of removing the inserted fiber and removing the inserted fiber after weaving the fabric in the form of a knitted or woven fabric using the inserted fiber for forming the gap between the carbon fiber yarn and the carbon fiber yarn and of the carbon fiber yarn The surface activation process of forming pores on the surface is performed simultaneously,
Method of manufacturing a drug-release carbon fiber stent, characterized in that by controlling the ratio of mixing the pitch to 0 to 100 parts by weight relative to 100 parts by weight of PAN in the spinning step, the size of the pores formed in the activation step.

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