Variable coating jig for stents with surface roughness and method for processing stents using the same

Abstract

The present invention provides a variable coating jig for a stent having a surface roughness, the variable coating jig including: a fixture shaft portion; a first block portion fixedly connected to one end of the fixture shaft portion; a second block portion arranged opposite the first block portion and variably arranged by sliding along the outer circumferential surface of the fixture shaft portion; and a surface region in which surface roughness is formed on at least one of the fixture shaft portion, the first block portion, and the second block portion.

Description

[Technical Field]

[0001] The present invention relates to a coating jig for a stent, and more particularly to a coating jig for a stent having a variable surface roughness that is used when applying a coating liquid to a stent to form a thin membrane. [Background technology]

[0002] Stents are widely used clinically to prevent narrowing of blood vessels and biliary tracts in the human body. Stents forcibly expand the area into which they are inserted, allowing for the smooth flow of long-term mediators (fluids such as body fluids and blood, gases, food, and enzymes). Stents are coated with a thin membrane on the exterior of the stent to prevent the penetration of tumor and cancer cells. The stent membrane is formed through a coating process using a coating tool. However, stents come in various shapes and sizes depending on the area in which they are used. Consequently, multiple coating tools must be installed. This poses problems of high process costs and space requirements.

[0003] Furthermore, conventional membranes have a tendency to be sticky due to their material properties. On the other hand, stents are deployed at the lesion site during treatment while inserted into an insertion device such as a catheter. Therefore, stents are stored while pre-inserted into the insertion device. During this process, external forces act on the stent, minimizing its diameter. As a result, the stent stretches and the membranes are stored in contact with each other for long periods of time.

[0004] As a result, the inner surface of the membrane can stick to itself partially when deployed with an insertion tool due to its material properties and the external environment, preventing it from returning to its original shape. To prevent this, the conventional stent manufacturing process includes a process of treating the membrane with expensive silicone powder or oil, which has been verified for biocompatibility. However, this process does not effectively solve the existing problems caused by stickiness. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been devised to solve the above problems by providing a variable-type coating jig for stents that can be used universally for stents of various shapes and sizes, thereby reducing the extremely high process costs required for conventional coating processes and minimizing the installation space occupied by the coating jig.

[0006] In addition, it is possible to provide a coating tool for a stent having a surface roughness that can reduce the adhesion of the membrane portion without adding an additional process to the conventional stent manufacturing process.

[0007] In addition, the company aims to provide a stent coating tool with surface roughness that can improve the existing stent production process without adding the process of applying expensive silicone powder or oil, thereby reducing stent production costs and improving price competitiveness.

[0008] Another object of the present invention is to provide a stent that can be effectively restored to its original shape when used in a procedure even if the stent has been stored in a catheter or the like for a long period of time. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, an embodiment of the present invention provides a variable surface roughness coating jig for a stent, including a jig shaft portion; a first block portion fixedly coupled to one end of the jig shaft portion; a second block portion disposed opposite the first block portion and variably disposed by sliding along the outer circumferential surface of the jig shaft portion; and a surface region in which surface roughness is formed in at least one of the jig shaft portion, the first block portion, and the second block portion.

[0010] It is preferable that the second block portion is fixed at any one position on the jig shaft portion, and the distance between the first block portion and the second block portion is continuously variable.

[0011] It is preferable that the jig shaft portion, the first block portion, and the second block portion have a coating area where a coating liquid is applied, and the jig shaft portion, the first block portion, and the second block portion further include a stopper portion disposed in a non-coating area other than the coating area and fixing the position of the second block portion.

[0012] The second block portion preferably includes a rotating body portion having a through hole formed in the rotation axis direction and communicating at both ends; and a ring-shaped groove portion formed at the lower end of the rotating body portion and concentric with the through hole.

[0013] It is preferable that the locking mechanism further includes a stopper portion that is accommodated and disposed in the groove portion to fix the position of the second block portion.

[0014] The surface region is preferably formed by randomly formed irregular recesses.

[0015] The surface roughness is preferably within a range of several tens to several hundreds of μm.

[0016] The surface roughness is preferably formed by a sandblasting process or an etching process.

[0017] A stent having a membrane portion formed through a coating process using a variable-type coating jig for a stent with surface roughness is provided.

[0018] Preferably, the inner surface of the membrane portion is formed with a micro-roughened surface to reduce adhesion between the membrane portions. [Effects of the Invention]

[0019] According to the means for solving the problems of the present invention as detailed above, various effects can be expected, including the following: However, the present invention is not valid unless it achieves all of the following effects.

[0020] The variable-type coating jig for stents according to an embodiment of the present invention can be used for stents of various shapes and sizes, thereby reducing the extremely high process costs required for conventional coating processes and minimizing the installation space occupied by the coating jig.

[0021] Furthermore, the coating jig for a stent having a rough surface according to an embodiment of the present invention can reduce the stickiness of the membrane portion without adding an additional process to the conventional process of manufacturing a stent.

[0022] Furthermore, the coating jig for a stent having a rough surface according to an embodiment of the present invention can improve the production process of the existing stent, thereby increasing price competitiveness.

[0023] Furthermore, the stent according to an embodiment of the present invention can be effectively restored to its original shape when used in surgery even if the stent is stored in a catheter or the like for a long period of time.

[0024] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned above will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a perspective view of a variable-type coating jig for a stent having a surface roughness according to an embodiment of the present invention. [Figure 2] FIG. 2 is an exploded perspective view of FIG. 1. [Figure 3] 10A and 10B are exemplary diagrams showing various combinations of a first block unit and a second block unit; [Figure 4] 10 is a diagram showing that the position of the second block part is continuously changed. [Figure 5] 2 is a diagram showing how a membrane portion is formed by the coating jig of FIG. 1. [Figure 6] 2 is a photograph showing the inner surface of a membrane portion formed by the coating jig of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0026] In order to fully understand the configuration and effects of the present disclosure, preferred embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, and may be embodied in various forms and may undergo various modifications. In the following description of the present invention, detailed descriptions of related known functions will be omitted if they are obvious to those skilled in the art and may unnecessarily obscure the gist of the present invention.

[0027] Terms such as "first," "second," etc. may be used to describe various components, but the components are not limited by these terms. These terms may be used only to distinguish one component from another. For example, a first component may be designated a "second component," and similarly, a second component may be designated a "first component," without departing from the scope of the present disclosure.

[0028] In this application, the use of terms such as "comprises" or "having" is intended to specify the presence of any feature, number, step, operation, component, part, or combination thereof described in the specification, but is understood not to preclude the possible presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0029] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless clearly indicated differently in the context. Terms used in the embodiments of the present disclosure may be interpreted in the sense commonly known to those skilled in the art unless otherwise defined.

[0030] Specific embodiments of the present invention will be described in detail below with reference to the drawings. Fig. 1 is a perspective view of a coating jig for a stent having a variable surface roughness according to one embodiment of the present invention, and Fig. 2 is an exploded perspective view of Fig. 1. Fig. 3 is an exemplary view showing various combinations of first and second blocks, and Fig. 4 is a view illustrating the continuous change in the position of the second block. Referring to Figs. 1 to 4, the coating jig J for a stent having a variable surface roughness according to one embodiment of the present invention includes a jig shaft portion 10, a first block portion 20, a second block portion 30, a surface region 40, a stopper portion 50, etc.

[0031] First, the stent S includes 1) a body portion 100 having a mesh structure formed by weaving wires in a zigzag pattern like a net, and 2) a membrane portion 200 formed as a thin membrane in the spaces, i.e., through holes, present between the wires in the mesh structure. The body portion 100 includes a hollow cylindrical tube portion 110 and an expanded tube portion 120 formed at one or both ends of the cylindrical tube portion 110. In this case, the coating jig J according to one embodiment forms a micro-roughened surface 300 on the membrane portion 200 during the process of forming the membrane portion 200 on the body portion 100 (see FIGS. 5 and 6).

[0032] The jig shaft 10 is a rod-shaped rotating element having a circular cross section with a constant radius r1 and extending longitudinally. The jig shaft 10 is coupled to a rotation drive unit D disposed outside the coating jig J so as to be axially rotated. One end of the jig shaft 10 is formed with a 1a coupling portion 12 that protrudes in the axial direction and has a male thread formed on its outer periphery. Corresponding to the 1a coupling portion 12, a 1b coupling portion in the form of a female thread groove is formed at the tip of the first block portion 20. The other end of the jig shaft 10 is formed with a second coupling portion 14 in the form of a groove so that the jig shaft 10 can be detachably coupled to the rotation drive unit D.

[0033] The first block unit 20 is fixedly coupled to one end of the jig shaft unit 10. Specifically, the first block unit 20 may be threadedly coupled to the jig shaft unit 10, thereby fixing the position of the first block unit 20. In contrast, the second block unit 30 is disposed opposite the first block unit 20 and variably positioned by sliding along the outer circumferential surface of the jig shaft unit 10. In one embodiment, the first block unit 20 and the second block unit 30 have one of a flange shape F1 and a flare shape F2. In this case, there are a total of four selectable combinations of the first block unit 20 and the second block unit 30. Alternatively, the first block unit 20 and the second block unit 30 may be designed to have one of various rotating body shapes.

[0034] Here, the flange shape F1 refers to a cylindrical shape with a constant radius r2. In this case, r2 is preferably larger than r1. The flare shape F2 refers to a truncated cone shape. In the flare shape F2, the radius r3 of the lower surface and the radius r4 of the upper surface are preferably larger than r1.

[0035] The second block part 30 may include a rotor part 32 having a through hole 34 formed in the rotation axis direction and communicating at both ends, and a ring-shaped groove part 36 formed at the lower end of the rotor part 32 and concentric with the through hole 34. At this time, a small gap may exist between the outer circumferential surface of the jig shaft part 10 and the inner circumferential surface of the second block part 30 formed by the through hole 34. When the second block part 30 is inserted into the jig shaft part 10 at the other end of the jig shaft part 10 through the through hole 34, the second block part 30 may slide in the length direction of the jig shaft part 10.

[0036] According to one embodiment, the second block portion 30 is fixed at any one position on the jig shaft portion 10, and the distance L between the first block portion 20 and the second block portion 30 is continuously variable. As described above, the second block portion 30 is disposed opposite the first block portion 20. When the first block portion 20 and / or the second block portion 30 have a flared shape F2, it is preferable that the first block portion 20 and / or the second block portion 30 be coupled in a direction in which the top surface of the flared shape F2 is inserted first into one end of the jig shaft portion 10.

[0037] In addition, the coating jig J according to an embodiment may further include a stopper portion 50 that fixes the position of the second block portion 30. However, the arrangement position of the stopper portion 50 may be limited to any one area. In the coating jig J according to an embodiment, a coating area C1 where a coating liquid C is applied is formed on the jig shaft portion 10, the first block portion 20, and the second block portion 30. The coating liquid C is a liquid material used to form the membrane portion 200 on the body portion 100. The coating area C1 may include a contact area of ​​the coating jig J that comes into contact with the body portion 100 when the body portion 100 is attached to the coating jig J.

[0038] The coating area C1 is a side surface of the first block member 20 and may include the entire side surface or a portion of the side surface. The coating area C1 is a side surface of the second block member 30 and may include the entire side surface or a portion of the side surface. The coating area C1 is a side surface of the jig shaft member 10 and may particularly include the entire outer surface of the jig shaft member 10 disposed between the first block member 20 and the second block member 30. Therefore, the coating jig J may have a non-coating area C2 in addition to the coating area C1. The non-coating area C2 is an area where the coating liquid C is not applied during the coating process.

[0039] According to one embodiment, the stopper portion 50 is preferably disposed in the non-coated region C2 other than the coated region C1. Meanwhile, the stopper portion 50 may be formed of a material with a high friction coefficient, for example, a rubber material such as synthetic resin. The stopper portion 50 may be disposed in the non-coated region C2, particularly in the groove 36 of the second block portion 30. In this case, the stopper portion 50 may have an O-ring shape. The stopper portion 50 is press-fitted into the space formed between the jig shaft portion 10 and the groove 36 to fix the position of the second block portion 30.

[0040] As a result, the variable-type coating jig (J) for stents according to one embodiment of the present invention can be used for stents (S) having various shapes and sizes. In addition, the extremely high process cost required for the conventional coating process can be reduced, and the installation space occupied by the coating jig (J) can be minimized.

[0041] Furthermore, the coating jig J according to one embodiment may further include a surface region 40 in which surface roughness is formed on at least one of the jig shaft portion 10, the first block portion 20, and the second block portion 30. The surface region 40 may be formed by a plurality of irregular recessed grooves formed in a disordered manner. Such recessed grooves do not have a uniform shape or pattern. The surface region 40 according to one embodiment is repetitive, excluding those formed by any one pattern having regular characteristics.

[0042] Meanwhile, the surface region 40 may be formed on the surface of the coating jig J, i.e., on the entire outer surface of the coating jig J. For example, the surface region 40 may be formed when the first block 20 and the second block 30 are assembled and coupled to the jig shaft 10. Alternatively, the surface region 40 may be formed on the entire outer surface of the jig shaft 10, the first block 20, and the second block 30 when they are separated and exist individually.

[0043] The surface roughness (roughness) of the surface region 40 can be expressed numerically. Specifically, the surface roughness of the coating jig J is preferably within a range of several tens to several hundreds of micrometers (μm). For example, the surface roughness of the coating jig J is preferably within a range of 30 to 300 μm. This surface roughness may vary depending on the components and viscosity of the coating liquid C.

[0044] After the coating process of forming the membrane part 200 in the coating jig J is completed, the stent S can be removed from the coating jig J. At this time, if the surface roughness of the surface region 40 exceeds 300 μm, the removal process of separating the stent S from the coating jig J becomes difficult. This is because the finely roughened surface 300 formed on the inner surface of the membrane part 200 makes it difficult for the stent S to be easily separated from the surface of the coating jig J. In addition, if the surface roughness of the surface region 40 is less than 30 μm, a conventional problem occurs due to stickiness between the inner surfaces of the membrane part 200.

[0045] The coating jig J (or the surface of the coating jig) may be formed of a synthetic resin, such as a polymer material. Alternatively, the coating jig J (or the surface of the coating jig) may be formed of a metal material. Here, the jig shaft portion 10, the first block portion 20, and the second block portion 30 may be formed of the same material. If the coating jig J is made of a polymer material, the coating jig J (or the jig shaft portion, the first block portion, and the second block portion, which are separated) may be subjected to a sandblasting process or an abrasive blasting process to form a surface roughness. A sandblasting process is a process in which fine particles of various materials are sprayed using compressed air to clean a surface. However, in one embodiment of the present invention, the sandblasting process is performed for the purpose of forming a surface roughness on the coating jig J.

[0046] The sandblasting process may vary conditions such as propellant, spray pressure, and spray time depending on the material and thickness of the coating jig J. Here, the propellant may be, for example, HA (Hydroxy Apatite), Zirconia, or Glass Bid. This sandblasting process may be performed at least once to minimize deviations in surface roughness.

[0047] Meanwhile, if the coating jig J is made of a metal material, surface roughness may be formed on the coating jig J (or the jig shaft portion, first block portion, and second block portion, which are separated) by an etching process. The coating jig J may be surface-treated through a multi-step etching process. This etching process may further include multiple pre-treatment and post-treatment steps. According to one embodiment, the etching process may be acid etching, which uses an acidic solution. For this purpose, an etching solution may be prepared in an etching bath. Then, the coating jig J may be immersed in the etching bath under preset temperature and time conditions, and its surface may be etched. Alternatively, the etching solution may be sprayed onto the surface of the coating jig J, for example, by a spray method.

[0048] As a result, the coating jig J can have a surface roughness having a uniform range of 30 to 300 μm within the surface region 40. Alternatively, a mechanical or chemical surface processing method can be used to form the surface roughness. The mechanical surface processing method can be, for example, a micro-knurling process.

[0049] When the other end of the jig shaft 10 is coupled to a rotation driver D, the coating jig J can be rotated about its axis with respect to the jig shaft 10. Meanwhile, the rotation driver D includes at least one electric motor M to provide driving force. When the body 100 is mounted on the coating jig J, the coating jig J can be rotated about its axis, allowing the polymer material to be uniformly coated on the body 100.

[0050] FIG. 5 is a diagram illustrating the formation of a membrane portion using the coating jig of FIG. 1. Referring to FIG. 5, the rotary driver D can be controlled according to a preset rotation speed, rotation period, etc. To start the coating process, a body portion 100 is first attached to the coating jig J. Then, as the coating jig J rotates, a polymer coating liquid C is applied to the body portion 100. This coating liquid C can be stored in a container such as a hopper. The coating liquid C can be sprayed in liquid form through a nozzle or sprayed. At this time, the coating liquid C can be spread over the entire body portion 100 due to centrifugal force generated by the rotation of the coating jig J. This allows the coating liquid C to be evenly applied to the body portion 100.

[0051] A stent S according to one embodiment of the present invention can be manufactured through a coating process using a variable-type coating jig J for a stent having a surface roughness. In the coating process, a coating liquid C is exposed to a predetermined temperature atmosphere. The coating liquid C hardens after a certain period of time. As a result, a membrane portion 200 is formed on the body portion 100. The coating process according to one embodiment includes a spinning operation of the coating jig J.

[0052] During the coating process, a micro-rough surface 300 is formed on the inner surface of the membrane unit 200 to reduce adhesion between the membrane units 200. The micro-rough surface 300 is formed during the process of curing the membrane unit 200. That is, the micro-rough surface 300 can be formed together with the membrane unit 200 in the following process: 1) the coating liquid C is first applied in an aerosol or liquid state to the coating jig J to which the body unit 100 is attached, 2) the coating jig J is then spun at a predetermined rotation speed, etc., and 3) the coating liquid C applied to the coating jig J is formed into the membrane unit 200 in a solid state.

[0053] As a result, the coating jig J for a stent having a rough surface according to one embodiment of the present invention can reduce the stickiness of the membrane part 200 without adding an additional process to the conventional process of manufacturing a stent S.

[0054] Figure 6 is a photograph showing the inner surface of the membrane portion formed by the coating jig of Figure 1. Referring to Figure 6, the stent S on which the membrane portion 200 is formed includes a body portion 100, a membrane portion 200, and a micro-roughened surface 300. Here, it is preferable that the membrane portion 200 is resistant to deformation and has high elasticity so that it can easily restore its original shape when external force is removed. In addition, it is preferable that the membrane portion 200 has material properties such as a smooth surface and an extremely low coefficient of friction.

[0055] Here, the fine rough surface 300 may be formed on the entire inner surface of the membrane unit 200 or at least a portion thereof, corresponding to the surface region 40. That is, the fine rough surface 300 according to one embodiment is not formed on the outer surface of the membrane unit 200. Also, a first region on which the fine rough surface 300 is formed and a second region on which the fine rough surface 300 is not formed may be alternately formed on the inner circumferential surface of the membrane unit 200.

[0056] Here, the micro-rough surface 300 may be formed by a plurality of irregular relief protrusions formed in a disorderly manner. Also, the micro-rough surface 300 may be formed by a plurality of irregular concaves and convexes, a plurality of irregular embossments, a plurality of irregular patterns, etc. That is, the micro-rough surface 300 according to an embodiment is repetitive, excluding those formed by any one type of pattern having regular characteristics.

[0057] The surface roughness of the micro-roughened surface 300 according to one embodiment may be in the range of several tens to several hundreds of micrometers (μm). The surface roughness of the micro-roughened surface 300 according to one embodiment is preferably in the range of 30 to 300 μm. As a result, the micro-roughened surface 300 according to one embodiment of the present invention can reduce the stickiness of the inner surface of the membrane part 200.

[0058] The micro-roughened surface 300 reduces surface contact with the inner surface of the membrane portion 200 when the stent S is stored in an insertion tool. As a result, the micro-roughened surface 300 can effectively prevent an increase in adhesion due to an increase in contact area with the inner space of the body portion 100. Furthermore, the stent S according to an embodiment of the present invention can effectively restore its original shape even when the stent S is stored for a long period of time in a catheter or the like due to the reduction in adhesion of the membrane portion 200.

[0059] Although the preferred embodiments of the present invention have been described above as examples, the scope of the present invention is not limited to such specific embodiments, but can be appropriately modified within the scope of the claims.

Claims

1. A jig for forming a membrane portion on a body portion of a stent, the membrane portion having a finely roughened inner surface and reduced adhesion between the membrane portions, a jig shaft portion having a male screw thread formed on the outer peripheral surface of one end thereof; a first block portion that is threadedly coupled to one end of the jig shaft portion through a female thread groove that corresponds to the male thread; a second block portion disposed opposite the first block portion and variably disposed by sliding along an outer circumferential surface of the jig shaft portion; a rotation drive unit that couples with the jig shaft and rotates the jig shaft; and surface regions in which surface roughness is formed on outer surfaces of the jig shaft portion, the first block portion, and the second block portion; the surface region is formed by irregular recesses formed in a disordered manner, rather than by any one pattern having regular characteristics; the surface roughness is in the range of 30 to 300 μm; The second block portion is a rotor portion having a through hole formed in the direction of the rotation axis and communicating at both ends; and a ring-shaped groove formed at the lower end of the rotor and concentric with the through-hole; A minute gap exists between the outer circumferential surface of the jig shaft portion and the through hole, a stopper portion that is accommodated in the ring-shaped groove portion and fixes the position of the second block portion, the stopper portion being press-fitted into a space formed between the jig shaft portion and the ring-shaped groove portion, the first block portion is fixed to an end of the jig shaft portion by screw connection, the second block portion is disposed between the first block portion and the rotation drive device, and a separation distance between the first block portion and the second block portion is changeable by movement of the second block portion; The first block portion and the second block portion are in the shape of a rotating body and are detachable so that they can be replaced with other blocks of different shapes. A variable coating jig for a stent having a surface roughness characterized by:

2. a coating area to which a coating liquid is applied is formed on the jig shaft portion, the first block portion, and the second block portion; a stopper portion disposed in a non-coated area other than the coated area and fixing the position of the second block portion; A variable coating jig for a stent having the surface roughness according to claim 1.

3. A membrane portion is formed on a body portion of a stent using the variable-type coating jig for a stent having a surface roughness according to claim 1. A method for fabricating a stent.

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