Filament using biodegradable polymer material, manufacturing device and method thereof

Abstract

The present invention is for manufacturing a biodegradable filament formed by spinning a hyaluronic acid solution, which is a high-viscosity biodegradable polymer raw material, into a gel type. The manufacturing apparatus according to the present invention comprises a spinning unit for forming a fibrous molded product by compressing and spinning a solution composed of a high-viscosity gel-state polymer mixture, a first drying unit for drying the molded product by transferring heat, a second drying unit for cooling the molded product, and a winding unit for recovering the molded product. Such a manufacturing apparatus can manufacture a filament having hyaluronic acid as the main component.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing filament yarn or fiber, and more specifically, to a method for manufacturing a biodegradable filament formed by spinning a hyaluronic acid solution, which is a high-viscosity biodegradable polymer raw material, into a gel type. Background Technology

[0002] Generally, hyaluronic acid (HA) is known as a biosynthetic natural substance that is abundant in the skin, and this hyaluronic acid is classified as a high-viscosity polysaccharide with a molecular weight ranging from 500,000 to 13,000,000 Da.

[0003] Hyaluronic acid is involved in various physiological activities in the human body and is known to possess diverse physiological activities depending on its molecular weight. In particular, high molecular weight hyaluronic acid is used as a space filler in the human body and is known to have functions such as anti-angiogenic and immunosuppressive effects.

[0004] As such, hyaluronic acid possesses excellent physical properties and various benefits, including moisturizing effects, lubrication against physical friction, and protection against bacterial invasion. Consequently, it is widely used as a material for cosmetics, pharmaceuticals, and quasi-pharmaceuticals, as well as in food products, serving as a cosmetic additive, arthritis treatment, surgical aid for ophthalmic surgery, and adhesion inhibitor after surgery. More specifically, hyaluronic acid is known to provide a lubricating effect that facilitates bodily movement, regulates the transport of physiologically active substances, acts as a mediator inducing cell differentiation and growth through specific interactions with cells, and serves as a support system for tissue-supporting proteins and glycoproteins such as collagen, elastin, and chondroitin sulfate within the extracellular matrix. Furthermore, it is known for its excellent water retention capacity and superior viscosity and elasticity.

[0005] Accordingly, recently, hyaluronic acid with a viscosity of 2.0 MDa or higher is being used in the form of a high-viscosity hydrogel and is widely utilized as an anti-adhesion agent for joint injections, cosmetic fillers, and internal and external surgical procedures.

[0006] However, most products are in the form of high-viscosity aqueous solutions or hydrogels, which limits usability, storage, and processability. In particular, when used in liquid form, the stability of hyaluronic acid itself is poor, requiring caution in the storage and distribution of the product. Furthermore, the actual hyaluronic acid content in the product is a low concentration of about 1 to 5%, making it impossible to administer high concentrations and high doses into the patient's body. Additionally, the injection pressure caused by the high volume results in significant pain for the patient.

[0007] In addition, when hyaluronic acid is administered into the body in liquid form, it is rapidly broken down by various enzymes present in the body, resulting in a decrease in molecular weight and consequently reduced persistence within the body, which has the disadvantage of diminishing effectiveness on the treatment site.

[0008] However, while manufacturing fibers using hyaluronic acid alone could increase the hyaluronic acid content, methods to manufacture fibers using only hyaluronic acid are generally limited due to the inability to melt caused by strong hydrogen bonds within the hyaluronic acid polymer polysaccharide.

[0009] In particular, hyaluronic acid has a very high water affinity compared to general polysaccharide polymers and a molecular weight of over 1,000,000 Da, so when preparing a spinning solution, the viscosity increases rapidly even at a low concentration of 1~2%, making wet spinning by extrusion very difficult. Additionally, it is difficult to remove excess water, which is the solvent, during the process, resulting in weak fiber properties. Furthermore, the low concentration of solids in the solvent leads to a very low process yield, making it difficult to manufacture hyaluronic acid fibers using a general wet spinning process.

[0010] Accordingly, conventionally, sodium hyaluronate fibers capable of being utilized as surgical sutures, cosmetic fillers, and tissue engineering scaffolds were manufactured by controlling the moisture content of non-melting hyaluronate salts through pretreatment and then melt-spinning them.

[0011] However, in the case of conventional melt spinning manufacturing methods, high-viscosity polymer gel-type raw materials are difficult to fiberize due to their slow solidification speed.

[0012] Accordingly, fiber yarns were manufactured by using thermosetting resins instead of thermoplastic resins and spinning a solution rather than a molten state to solidify it; however, solidifying with hot air takes a long time and causes problems such as browning or yarn breakage including cracks.

[0013] In particular, when solidifying molded products with hot air as in the conventional method, there are issues such as the need for a very long time or the easy occurrence of breakage. Furthermore, if the product is attached to a conveyor belt for transport or a winder for winding before it is sufficiently solidified, the circular fiber shape collapses, causing it to change shape into an ellipse or film, and ultimately resulting in a problem where the fiber shape is not maintained during solidification.

[0014] In addition, the wet spinning method also has complex processes and environmental issues because it requires the use of organic solvents or coagulation solutions for acid-base reactions.

[0015] As such, when high-viscosity polymer gels are manufactured into filaments by melt spinning or wet spinning methods, a new manufacturing method is required due to the slow solidification speed of the high-viscosity polymer gels and various other problems. Prior art literature

[0016] Republic of Korea Registered Patent No. 10-1709608 (Registered on Feb. 17, 2017) The problem to be solved

[0017] The present invention has been devised to solve the aforementioned problems, and the objective of the present invention is to provide a manufacturing apparatus and a manufacturing method capable of manufacturing a filament having hyaluronic acid as the main component.

[0018] Furthermore, the objective of the present invention is to provide a filament manufacturing apparatus and a manufacturing method capable of rapidly drying and solidifying a manufactured molded article by a heat transfer method using conductive heat while the article is attached to a heated surface.

[0019] In addition, the objective of the present invention is to provide a filament manufacturing apparatus and a manufacturing method capable of preventing deformation of the shape of the molded article while it is drying. means of solving the problem

[0020] According to the method for manufacturing a filament of the present invention for achieving the aforementioned purpose, the method may include a solution preparation step of mixing a polymer mixture in a high-viscosity gel state without melting or heating by heat, a molding article manufacturing step of forming a fibrous molded article by compression spinning the polymer mixture at room temperature, and a molding article drying step of drying the molded article. By this manufacturing method, a filament made of a biodegradable or bio-implantable polymer can be manufactured.

[0021] According to the present embodiment, in the solution preparation step, the polymer mixture may contain a biodegradable polymer at a concentration of 5 w% or more and 20 w% or less based on the weight of the total solution.

[0022] According to the present embodiment, the biodegradable polymer may include hyaluronic acid (HA).

[0023] According to the present embodiment, the polymer mixture may further include a functional agent at a concentration of 5 w% or more and 15 w% or less based on the weight of the total solution.

[0024] According to the present embodiment, the molding drying step may include a transfer step in which the molded product is transferred in a state of contact and attachment to the surface of a rod-shaped heating roller with a heated surface, while rotating the molded product without stretching it to minimize shape deformation; a curing step in which heat is transferred to the molded product through the heating roller; and a winding step in which the molded product is wound onto a winding roller and recovered.

[0025] According to the present embodiment, a cooling step for cooling the molded product between the heating step and the winding step may be further included. In the cooling step, the molded product transferred from the heating roller is wound in a winding manner by a cooling roller at room temperature spaced apart laterally from the heating roller and delivered to the winding roller. In the molded product drying step, the heating roller may include a first region, which is a section where the molded product is first contacted and heated / dried, and a second region, which is a low-gravity section, where the molded product is heated / dried while hanging from the bottom under the influence of gravity during rotation after the first region.

[0026] According to the present embodiment, the discharge amount of the mixture extruded during the molding product manufacturing step is 0.05 g / min to 0.5 g / min, the heating temperature of the heating roller during the molding product drying step is 40℃ or higher and 150℃ or lower, and the conveying speed of the molding product by the rotation of the heating roller is 0.3 m / min or higher and 2.0 m / min or lower.

[0027] In addition, according to the filament manufacturing method of the present invention, it may include a spinning section for forming a fibrous molded article by compressing and spinning a solution composed of a high-viscosity gel-state polymer mixture, a first drying section for drying the molded article by transferring heat, a second drying section for cooling the molded article, and a winding section for recovering the molded article.

[0028] According to the present embodiment, the first drying unit may include a heating roller that transfers heat generated inside to the surface.

[0029] According to the present embodiment, the first drying unit is characterized in that the surface of the heating roller is coated with a hydrophobic polymer. Effects of the invention

[0030] According to the manufacturing apparatus and method using a biodegradable filament polymer as a raw material according to the present invention as described above, a biodegradable filament can be manufactured by spinning a biodegradable polymer raw material into a high-viscosity gel type. Here, the biodegradable filament according to the present invention can be formed by using a biodegradable polymer raw material and compressively spinning a high-viscosity gel-state solution, and the spun molded product can be finally manufactured into a fiber-shaped product as it solidifies while undergoing a drying process on the surface of a heated roller. The biodegradable filament manufactured according to one embodiment of the present invention can be applied to biocompatible products.

[0031] According to the filament manufacturing apparatus and method of the present invention, a mixture solution that is not melted by heat under room temperature conditions is compressed and spun to form a molded product from a high-viscosity biodegradable polymer raw material. Since the molded product is transported in an attached state to a heating roller with a heated surface and heat is directly transferred to the surface of the molded product by the heating surface of the roller, the molded product can be dried and solidified by a heat transfer method. Therefore, the invention differs from conventional drying methods following melt spinning or wet spinning in that the molded product is formed under room temperature conditions, and the drying and curing process of the molded product is performed by applying direct heat via a heat conduction method rather than through hot air or solvents. In other words, the present invention rapidly cures the molded product manufactured under room temperature conditions, thereby shortening the drying time of the molded product and preventing shape deformation during the drying process, so that the shape of the fiber can be maintained. In particular, compared to the conventional indirect drying method using hot air after melt spinning, it has the advantage of shortening the time and improving the production speed.

[0032] In addition, according to the present embodiment, unlike wet spinning which requires the use of a conventional coagulation bath, it prevents the generation of wastewater, thereby providing environmental advantages, and solves additional drying problems caused by the coagulation solution, thereby significantly shortening production and drying times.

[0033] Accordingly, according to the present invention, a biodegradable filament can be manufactured by utilizing hyaluronic acid, which has a limited manufacturing environment, as a raw material.

[0034] Furthermore, according to the present invention, the drying time of the molded product can be shortened and the production speed can be improved, which is an advantage.

[0035] In addition, according to the present invention, shape deformation of the molded article is prevented during the drying process through rapid drying, so a product that stably maintains the cross-sectional shape of the fiber can be manufactured. Brief explanation of the drawing

[0036] FIG. 1 is a schematic diagram illustrating a manufacturing apparatus and a manufacturing process for manufacturing a filament according to one embodiment of the present invention. FIG. 2 is a schematic diagram illustrating the configuration for heating and drying of a filament manufacturing apparatus according to one embodiment of the present invention. FIGS. 3 to 5 are drawings illustrating modified examples of the filament manufacturing apparatus of the present invention. FIGS. 6 and 7 are schematic diagrams illustrating the flow of a filament manufacturing method according to one embodiment of the present invention. FIGS. 8 and 9 are drawings illustrating optical microscope images of hyaluronic acid filament samples prepared under different manufacturing conditions by a filament manufacturing method according to one embodiment of the present invention. FIG. 10 is a graph showing the fiber diameter size changed according to the amount of functional agent added for a filament product manufactured by a filament manufacturing method according to one embodiment of the present invention. FIG. 11 is an image showing optical microscope photographs of filament products manufactured by a filament manufacturing method according to one embodiment of the present invention, showing different shapes depending on the amount of functional agent added. Specific details for implementing the invention

[0037] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms.

[0038] Hereinafter, the technical features of the present invention will be specifically described with reference to the attached drawings.

[0039] According to the filament manufacturing apparatus and manufacturing method of one embodiment of the present invention, a biodegradable or biocompatible filament can be manufactured by spinning a biodegradable polymer raw material into a high-viscosity gel type.

[0040] The biodegradable filament according to the present invention can be formed by using a biodegradable polymer raw material and compressively spinning a high-viscosity gel-state solution, and the spun molded product can be finally manufactured into a fiber-shaped product as it solidifies while undergoing a drying process on the surface of a heated roller. The biodegradable filament can be classified as a fiber having a continuous length.

[0041] The biodegradable filament manufactured according to one embodiment of the present invention can be applied to biocompatible products.

[0042] For example, the biodegradable filament according to the present invention can be utilized as a drug delivery support, such as a surgical suture or a cosmetic filler. Here, the biodegradable filament does not require strength and, as a linear polymer material, can maintain its shape for a certain period of time. That is, the biodegradable filament of the present invention can also be used as a medical scaffold. Furthermore, since the biodegradable filament decomposes after a certain period of time, it can also be utilized as a material absorbed by the human body.

[0043] To manufacture biodegradable filaments used as medical scaffolds, various biodegradable or biocompatible polymers can be used.

[0044] For example, biodegradable polymers are polymers whose form and weight gradually disappear as they undergo slow chemical degradation within the body; representative natural polymers include collagen, fibronectin, gelatin, chitosan, and alginic acid, while synthetic polymers include poly(lactic acid) (PLA), poly(glycolic acid) (PGA), poly(D,L-lactic-co-glycolic acid) (PLGA) and their similar copolymers, as well as poly(ε-caprolactone) (PCL), polyanhydrides, and polyorthoesters.

[0045] In addition, biocompatible polymers include agarose, fibrin, Matrigel, starch, cellulose, alginate, hyaluronic acid, sodium hyaluronate, polyvinyl alcohol (PVA), pectin, carrageenan, chondroitin (sulfate), dextran (sulfate), polylysine, carboxymethyltitin, pullulan, polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), hydroxypropylmethylcellulose (HPMC), sodium carboxymethylcellulose, polyalcohol, gum arabic, cyclodextrin, dextrin, glucose, fructose, trehalose, glucose, maltose, lactose, lactulose, fructose, turanose, melitose, melesitose, It can be selected from the group consisting of dextran, sorbitol, xylitol, palatinite, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, polymethacrylic acid, and polymaleic acid chitosan.

[0046] In the following embodiments of the present invention, a filament is manufactured using hyaluronic acid (HA) as the main raw material, but a filament may be manufactured using one or more of the aforementioned biodegradable or biocompatible polymers in addition to hyaluronic acid.

[0047] The following describes in detail the process of manufacturing biodegradable filaments.

[0048] First, FIG. 1 is a schematic diagram illustrating a manufacturing apparatus and a manufacturing process for manufacturing a filament according to one embodiment of the present invention.

[0049] Referring to FIG. 1, according to one embodiment of the present invention, a device for manufacturing a filament may be configured to include a spinning unit (110), a first drying unit (120), a second drying unit (130), and a winding unit (140).

[0050] The spinning unit (110) can manufacture a fibrous molded article (1a) by compressing and spinning a solution containing a biodegradable polymer raw material in one direction. The spinning unit (110) may be composed of a gel spinning unit and includes a syringe and a syringe pump with a needle connected to the end. The needle consists of a nozzle with a circular cross-section. Gel spinning is a method of manufacturing synthetic fibers by spinning a high-concentration polymer solution or a plasticized gel through a nozzle to form fibers through cooling, volatilization, and solidification. This spinning unit (110) pressurizes the solution inside the syringe by the syringe pump and passes it through the needle at the end of the syringe, thereby forming a fibrous shape through the needle. The fiber shape is manufactured as an unoriented yarn. At this time, the spinning unit (110) can manufacture a molded article (1a) by compressing and spinning a solution without applying heat under room temperature conditions and discharging it in one direction. That is, the solution introduced into the spinning unit (110) exists in a high-viscosity gel state and is formed into a fibrous molded product (1a) in the form of strands as it passes through the needle while being pressurized by the compression spinning method. For example, the biodegradable polymer raw material produced into the molded product (1a) by the spinning unit (110) may include hyaluronic acid polymer.

[0051] The molded product (1a) extruded from the spinning unit (110) is formed into a fibrous strand with a circular cross-section and can be provided as a final filament-shaped product after passing through the first drying unit (120), the second drying unit (130), and the winding unit (140) described later.

[0052] The first drying unit (120) is for drying to achieve a solidified or hardened state of the molded product (1a) and may be positioned at a distance from the radiating unit (110). The first drying unit (120) may be positioned downwardly spaced apart from the radiating unit (110) and collects the molded product (1a) formed from the radiating unit (110) positioned above the first drying unit (120).

[0053] Here, the radiating section (110) may be positioned downward such that the discharge port (not shown) for discharging the molded product (1a) faces the first drying section (120). Additionally, the arrangement structure of the radiating section (110) with the first drying section (120) may be vertical as shown in the drawing, but it may also be arranged in a diagonally intersecting position, and in any structure, it is preferable that the discharge port faces the surface of the first drying section (120).

[0054] Referring again to the drawing, the first drying unit (120) is configured in the form of a roller that rotates in one direction, so that the molded product (1a) can be transported by winding it by rotation. Since the molded product (1a) collected in the first drying unit (120) is formed from a high-viscosity solution, it has a certain viscosity and is provided in a state that can be attached to the surface of the first drying unit (120). In this embodiment, the first drying unit (120) provides a drying section of a certain length for a certain period of time as it transports the molded product (1a) while rotating clockwise with the molded product (1a) attached.

[0055] In this case, according to one embodiment, the first drying unit (120) may be formed in a structure capable of directly transferring heat to the molded product (1a). For example, the first drying unit (120) may be configured to include a surface heating type heating roller.

[0056] This first drying unit (120) can transfer heat to the outside through the heating surface of the heating roller as the heating roller heats itself, and as the molded product (1a) is transported while rotating with the molded product (1a) attached to the surface of the heating roller, the molded product (1a) placed in contact with or adjacent to the roller surface is heated and dried through heat transfer by the surface for a certain period of time. Most of the molded product (1a) remains in contact with the roller surface.

[0057] Here, the heating roller may be coated to have a hydrophobic surface. For example, the surface of the heating roller may be coated with a hydrophobic polymer, and according to one embodiment, a material called Polytetrafluoroethylene (PTFE), commonly known as Teflon, may be used. Accordingly, the heating roller prevents the molded article (1a), which is a high-viscosity material, from being deformed by surface tension even if the molded article (1a), formed from a gel-state solution, is attached to the surface. That is, the first drying section (120) can prevent the molded article (1a) from being deformed into an elliptical or film-like shape by being pressed by a force acting in the direction of gravity from a circular shape in cross-section.

[0058] Meanwhile, the first drying unit (120) may be configured to control the rotational speed of the heating roller and the surface temperature. To this end, although not illustrated, the first drying unit (120) may include a speed controller and a temperature controller for controlling the heating roller, and the rotational speed and surface temperature of the heating roller may be controlled by each controller.

[0059] In this way, the first drying unit (120) dries the manufactured molded product (1a) by a heat transfer method using conductive heat while the molded product (1a) is attached to a heated surface, so that the molded product (1a) can be quickly solidified.

[0060] As such, according to an embodiment of the present invention, the first drying unit (120) is for drying a molded product (1a). Since sufficient surface hardening is possible by performing heat drying while the molded product (1a) is wound without being stretched by a heating roller and transported in one direction, a stable drying operation can be performed, thereby preventing the shape of the molded product (1a) from being deformed in an unhardened state after molding. The process of drying the molded product (1a) through the first drying unit (120) will be described later.

[0061] The second drying unit (130) may be positioned apart from the first drying unit (120). According to one embodiment, the second drying unit (130) may be positioned spaced apart laterally from the first drying unit (120). This second drying unit (130) allows the solidified material (1b) transported from the first drying unit (120) to be transported in one direction.

[0062] Referring to the drawing, the second drying unit (130) is configured in the form of a roller that rotates in a different direction from the first drying unit (120), so that the solidified material (1b) can be transported in one direction by winding it by rotation. In this case, according to one embodiment, the second drying unit (130) may include a cooling roller at room temperature that is not heated, unlike the first drying unit (120). The cooling roller may be provided as a winding roller, and the solidified material (1b) is wound by this cooling roller and transported in one direction. In this embodiment, as the second drying unit (130) transports the solidified material (1b), it provides an additional drying section of a predetermined length for a certain period of time, which can serve as a cooling section for the solidified material (1b).

[0063] Here, the second drying section (130) may be a component included in the winding section (140) described later, but in this embodiment, it is preferable to provide an additional component to provide an additional room temperature drying (or cooling) section after the heating drying section by the first drying section (120), and the winding roller may be rotated in conjunction with the operation of the roller of the first drying section (120) or the winding section (140).

[0064] Thus, the second drying unit (130) can wind up the solidified material (1b) and transport it in one direction, and perform a drying process in which the solidified material (1b) can be sufficiently cooled while being transported by a roller. That is, most of the solidified material (1b) transported from the second drying unit (130) is heated and dried by the first drying unit (120) and delivered in a state where the surface is sufficiently hardened; however, since the temperature of the solidified material (1b) is raised during the heating and drying process, there is a problem that the shape may be deformed if it is immediately delivered to the winding unit (140) and wound up.

[0065] Accordingly, the second drying unit (130) performs additional drying at room temperature after heating and drying, so that the temperature of the product can be lowered by sufficiently drying the inside of the cross-section of the fiber, thereby preventing the fiber shape from being deformed during the conveying and winding process.

[0066] The winding unit (140) is for recovering a fiber-shaped filament product (1c) and may be positioned apart from the first drying unit (120) and the second drying unit (130). This winding unit (140) may include at least one winding roller positioned laterally apart from the second drying unit (130), and the winding roller may be provided as a winding roller. The winding unit (140) is able to wind and recover the product (1c) that has passed through the second drying unit (130). In some cases, the winding unit (140) may receive the product directly from the first drying unit (120).

[0067] Referring to the drawing, the winding unit (140) is configured in the form of a roller that rotates in one direction, so that the product (1c) can be wound by a rotational method. The winding unit (140) rotates in a direction corresponding to the rotational direction of the first drying unit (120) and can retrieve the product (1c). In this way, the product (1c) exists as a fibrous member and is wound onto the retrieval roller in the form of a roll.

[0068] Meanwhile, FIG. 2 schematically illustrates a first drying unit (120) of a filament manufacturing device according to one embodiment of the present invention. FIGS. 3 to 5 are drawings illustrating modified examples of the filament manufacturing device of the present invention.

[0069] Referring to FIGS. 2 to 5, when the radiating unit (110) is positioned perpendicular to the first drying unit (120), the first drying unit (120) may have a heating drying section from a first point (A), which is a 0° position where the molded product (1a) begins to come into contact with the center and surface of the heating roller, to a fifth point (E), which is a maximum 315° position as the last part where the molded product (1a) is transferred to the next section. In this embodiment, the fifth point (E) may be formed at any point within a range exceeding 315° and less than 360°, but it is preferable to form it within the maximum value range, as structural interference may occur if the first point (A) and the fifth point (E), where the molded product (1a) produced by the radiating unit (110) is collected, are formed too close together.

[0070] At this time, since the first drying section (120) is structured such that the entire surface of the heating roller is heated and rotated, the entire area can be used as a heating and drying section; however, due to the continuous production structure, the actual position where the molded product (1a) is placed in contact with or adjacent to the heating roller in an attached state is formed within the AE section. That is, for the purpose of explanation in this embodiment, the attachment position of the reference molded product (1a) is described as moving from the first point (A) to the fifth point (E) of the heating roller.

[0071] Additionally, the heating and drying section may be formed up to the fifth point (E), which is an angle range exceeding 270°, but may be formed up to the fourth point (D) or within the CD section, which is less than 270°. In other words, the fifth point (E) may be formed at any location within the DA section, but may be formed within the DE section or the CD section, and may be set as points C, D, E, and F. These heating and drying sections may be changed as needed and may be set in various ways as shown in FIG. 1 and FIG. 3 to 5 by the diameter size, spacing, or installation height of the first drying section (120) and the second drying section (130). For example, the roller diameter size of each drying section and winding section may be formed to be between 200mm and 900mm, and each may consist of a single roller or multiple rollers. The size of these rollers may vary depending on the manufacturing environment, but since they limit the length of the heating drying or cooling drying section, it is desirable to set them for an appropriate drying time.

[0072] Here, the first drying section (120) is rotated in the AB section, which is from the first point (A) to the second point (B), so that the molded product (1a) is attached to and in contact with the heating surface of the heating roller, thereby transporting the molded product (1a). In the AB section, the molded product (1a) is in contact with the heating surface of the first drying section (120), and sufficient conductive heat is applied by the heating roller, so it can be solidified quickly, and the shape of the fiber formed by the spinning method can be stably maintained and transported. The first area for drying within the heating drying section can be defined as the AB section.

[0073] In addition, the first drying section (120) transports the molded product (1a) in the BC and CD sections, which are from the second point (B) to the third point (C) and from the third point (C) to the fourth point (D), respectively, in a manner where only a part of the molded product (1a) is attached due to the influence of gravity, and the remaining parts are positioned adjacent to the heating roller. That is, in the BC and CD sections, the molded product (1a) is suspended from the lower part of the roller due to gravity, so deformation caused by contact with the roller surface can be prevented. In this way, the first drying section (120) hardens the surface of the molded product (1a) by transferring heat in a low-gravity state in the BC and CD sections. The second area for drying within the heating drying section can be defined as the BD section. The second area is a low-gravity section, which minimizes shape deformation of the fiber while performing heating drying.

[0074] Next, the first drying section (120) sets the fifth point (E) at the position before and after the fourth point (D), and transfers heat so that the molded product (1a) is sufficiently surface-hardened while being transported to the fifth point (E).

[0075] At the fifth point (E), the solidified material (1b), which is in a solidified state from the molded product (1a), is separated and detached and transferred to and wound into the second drying section (130) at an adjacent location. It acts as a transfer section for the next step from the second area onwards.

[0076] At this time, in the initial stage where manufacturing begins, the solidified material (1b) that is wound and transported to the first drying unit (120) is separated by a worker and transferred to the second drying unit (130), and thereafter, the solidified material (1b) is continuously wound from the first drying unit (120) to the second drying unit (130), maintaining a state of continuous production.

[0077] In this way, the first drying section (120) dries the molded product (1a) by transferring heat from the heating roller to the surface.

[0078] Here, according to the present embodiment, the manufacturing device first dries the molded product (1a) by the first drying unit (120) and transfers the solidified product (1b), which is in a solidified state, to the second drying unit (130). The position or angle of the second drying unit (130) may be changed depending on the position of the fifth point (E). That is, in order to maintain appropriate tension and angle between the rollers so that a smooth transfer state can be provided, the position of the second drying unit (130) or the winding unit (140) may be changed relatively. That is, as shown in FIGS. 1 to FIGS. 3 to 5, the position of the second drying unit (130) may be changed according to the change of the fifth point (E). FIG. 1 shows the fifth point formed near area F of FIG. 2, FIG. 3 shows the fifth point formed in area C, FIG. 4 shows the fifth point formed in area D, and FIG. 5 shows the fifth point formed in area E.

[0079] The solidified material (1b) transferred to the second drying unit (130) is transferred to a natural cooling state and further drying is performed, and the product (1c) that has been dried is wound by the winding unit (140) and finally recovered in the product state.

[0080] In this way, in this embodiment, a heating drying section can be provided by the first drying section (120).

[0081] Additionally, the first drying unit (120) may be set to a heating temperature in the range of 30°C to 150°C, and preferably formed in the range of 35°C to 55°C. For example, the first drying unit (120) may be set to a heating temperature of about 40°C or 50°C. Here, if the heating surface temperature of the heating roller of the first drying unit (120) is set to less than 30°C, the difference from the drying or solidification speed at room temperature is not significant, so it can meet the heating requirements, and if it exceeds 150°C, there is a problem in that the fiber is deformed into carbonized material or yarn breakage occurs.

[0082] As will be described later, for example, the first drying section (120) may dry the molded product (1a) under conditions of approximately 120°C, which is a relatively high temperature. In this case, it is desirable to increase the rotation speed of the heating roller to transport the molded product (1a) within a short time, thereby reducing the contact time and preventing the molded product from being exposed to the high temperature for a long time.

[0083] Thus, according to one embodiment of the present invention, a filament manufacturing apparatus can form a molded product by compression spinning a mixture solution from a high-viscosity biodegradable polymer raw material in a state that is not melted by heat under room temperature conditions, and then dry and solidify the molded product by a heat transfer method by directly transferring heat to the surface of the molded product through the heating surface of the heating roller while the product is transported in an attached state to a heating roller with a heated surface.

[0084] At this time, the present invention is designed to differ from conventional drying methods after melt spinning or wet spinning in that it forms a molded product under room temperature conditions and performs the drying and curing process of the molded product by applying direct heat through a heat conduction method rather than through hot air or a solvent.

[0085] Accordingly, the present invention rapidly cures a molded product manufactured under room temperature conditions to shorten the drying time of the molded product and prevents shape deformation during the drying process, thereby allowing the shape of the fiber to be maintained. In particular, compared to the conventional indirect drying method using hot air after melt spinning, it has the advantage of shortening the time and improving the production speed.

[0086] In addition, according to the present embodiment, unlike wet spinning which requires the use of a conventional coagulation bath, it prevents the generation of wastewater, thereby providing environmental advantages, and solves additional drying problems caused by the coagulation solution, thereby significantly shortening production and drying times.

[0087] As such, according to one embodiment of the present invention, the filament manufacturing apparatus uses a drying method through direct surface heat transfer rather than a drying method using cooling air, heating air, or a coagulating liquid, and performs the drying operation while transporting the molded product using a roller, thereby resolving the problems that occur during the conventional drying process.

[0088] In particular, the present invention uses hyaluronic acid as a biodegradable polymer, enabling the production of high-content hyaluronic acid filaments by overcoming the limited manufacturing environment of hyaluronic acid. That is, the present invention enables the production of hyaluronic acid filaments with hyaluronic acid as the main component, which has excellent biocompatibility, skin elasticity function, and moisture retention capacity.

[0089] Meanwhile, according to one embodiment of the present invention, a filament manufacturing method can be performed using the aforementioned filament manufacturing apparatus.

[0090] FIGS. 6 and 7 are schematic diagrams illustrating the flow of a filament manufacturing method according to one embodiment of the present invention.

[0091] Referring to FIG. 6, the filament manufacturing method of the present invention may include a solution manufacturing step (S110), a molded product manufacturing step (S120), and a drying step (S130). For example, the present embodiment describes a method for manufacturing a filament using a hyaluronic acid polymer.

[0092] In the solution preparation step (S110), a solution can be prepared by mixing a polymer mixture in a high-viscosity gel state. First, the polymer is dissolved in distilled water (DI Water) to prepare the solution. The concentration of the polymer mixture solution can be set to approximately 5% to 20%, and for example, a hyaluronic acid solution with a concentration of approximately 10% can be prepared. Here, in the case of manufacturing conditions for hyaluronic acid fibers produced through conventional melt spinning or wet spinning, the concentration of the solution used is approximately 2-3%, so there is a problem of low manufacturing yield due to the low concentration; however, in this embodiment, a solution in a high-viscosity state of approximately 10% is used to increase the manufacturing yield (improved from the existing 2-3% to 10%). The mixture solution is prepared by mechanical stirring under room temperature conditions. Accordingly, the polymer mixture can be prepared, and the prepared polymer mixture solution can be stored in the solution supply and storage tank of the spinning unit for spinning.

[0093] In this case, according to the present embodiment, when a filament produced from a solution is utilized as a medical scaffold, a drug delivery support, or a drug delivery system (DDS), it may be made to contain factors other than hyaluronic acid to perform additional functions. For example, if necessary, 5 to 15% of a functional agent (additive) may be added to a 10% hyaluronic acid solution, and such functional agent may be included in the filament produced from the hyaluronic acid solution to control physical properties such as degradation period or strength, or to perform the inherent function of the agent. The functional agent may be provided in powder form by selecting either the aforementioned biodegradable polymer or biocompatible polymer, and when such a functional agent is added, the mixture solution may be prepared as a suspension.

[0094] In the molding product manufacturing step (S120), a polymer mixture solution is compressed and extruded from a syringe pump through an outlet. At this time, the solution is filled or supplied to the syringe, and the solution inside the syringe is pressurized by the syringe pump and passed through the needle at the end of the syringe, thereby forming a fibrous structure through the needle. Accordingly, the solution can be manufactured into a fibrous molded product. That is, the molding product manufacturing step (S120) involves extruding the polymer mixture solution under room temperature conditions, enabling the manufacture of a fiber-shaped product. If a functional agent is included, the polymer used as the functional agent may exist in the form of fine particles in the fiber-shaped product.

[0095] After forming a molded product by compression spinning the polymer mixture in this way, the manufactured molded product is dried in the drying step (S130).

[0096] In the drying step (S130), the molded product manufactured by spinning from the mixture is dried. At this time, the molded product undergoes a drying process and a recovery process while being transported by a plurality of rollers as in the manufacturing device described above. Specifically, the drying step (S130) may include a transport step for transporting the molded product, a curing step (S131), and a cooling step (S132), and a winding step (S133) may be subsequently performed after the curing step (S131) ​​and the cooling step (S132).

[0097] In the curing step (S131), heat can be applied to the molded product to dry it. For this purpose, a surface-heating type heating roller may be used, and the molded product formed in the aforementioned molded product manufacturing step (S120) is attached to the surface of the heating roller and transported according to the rotation of the roller. As the surface of the heating roller is heated, heat is transferred to the molded product, and the molded product is continuously transported as it rotates in one direction.

[0098] In this way, the molded product can be transported while attached to the surface of the heating roller and wound. At this time, the molded product undergoes a drying process by directly receiving heat through the heated surface of the heating roller, which is heated by the surface heating method.

[0099] Accordingly, the molded product, which is in a viscous state, is rapidly cured by a thermal drying method and can solidify into the originally formed fibrous structure without deformation. In other words, since the molded product is rapidly dried while being directly heated by the surface heating method of the heating roll, its shape can be maintained without deformation.

[0100] In other words, since the shape of the fiber may be deformed in an undried state, rapid drying allows for short-term surface hardening so that the shape on the fiber can be maintained and fixed without deformation in the required product shape.

[0101] In addition, the heating surface of the heating roller can be coated with Teflon to provide hydrophobicity, and as the molded product is transported with the molded product attached to the surface of the heating roller, heat is transferred through the heating surface to perform a drying operation of the molded product, thereby minimizing shape deformation.

[0102] In the cooling step (S132), the molded product can be cooled at room temperature to perform a drying process. To this end, the molded product solidified on the heating roller is transferred from the heating roller to a rotary winding roller installed adjacent to it, and the transferred molded product is conveyed in one direction by the rotary winding roller and passes through a cooling section under room temperature conditions. Accordingly, the molded product to which heat was applied by the heating drying method can be cooled.

[0103] In this way, the molded product can be dried and fixed in the form of a product through the drying step (S130).

[0104] In the winding step (S133), the molded product conveyed by the winding roller can be conveyed to an adjacent winding roller and can be recovered as a final product while being wound by the rotating winding roller.

[0105] As such, according to the filament manufacturing method of the embodiment of the present invention, the drying time of the molded product formed by spinning can be shortened by drying the molded product through a heat transfer method via a heated surface by a heating roller.

[0106] In addition, the present invention prevents shape deformation during the drying process, thereby allowing the shape of the fiber to be maintained. That is, according to the present invention, the extruded molded product is attached to a heated surface and directly heated and cured by a heat transfer method through the surface, thereby preventing shape deformation of the fiber through rapid curing.

[0107] Furthermore, the present invention uses a heating roller in the shape of a rod rather than a conventional plate-shaped heating plate for drying the molded product, and allows the molded product attached to the top to be transported while rotating together with the rotating roller as it is ejected from the top of the heating roller. Accordingly, the ejected molded product can be transported from the top through the sides and bottom of the heating roller, and undergoes a rapid solidification process in a form that hangs from the heating roller due to the influence of gravity, even though a portion of it is attached to the heating surface, thereby forming a fixed fibrous shape. In other words, the molded product's circular cross-sectional shape can be prevented from being flattened by gravity. That is to say, the present invention can provide a manufacturing environment under low-gravity conditions so that shape deformation due to gravity does not occur in the molded product.

[0108] Here, since hydrophobicity is imparted to the heating surface of a heating roller coated with a polymer such as Teflon, a molded article made from a water-soluble high-viscosity polymer gel is formed into a circular filament and then adheres to the heating surface of the heating roller, thereby preventing the phenomenon in which the cross-section of the circular fiber shape collapses, such as an ellipse or a film, due to surface tension.

[0109] Ultimately, according to the present invention, a mixture solution that is not melted by heat under room temperature conditions is compressed and spun to form a molded product from a high-viscosity biodegradable polymer raw material, and the molded product can be dried and solidified by a heat transfer method by directly transferring heat to the surface of the molded product through the heated surface of the heating roller while being transported in an attached state to a heating roller with a heated surface.

[0110] Therefore, the present invention can manufacture biodegradable filaments by utilizing hyaluronic acid, which has a limited manufacturing environment, as a raw material.

[0111] In addition, the present invention has the advantage of being able to shorten the drying time of the molded product and improve the production speed.

[0112] In addition, the present invention prevents deformation of the molded product during the drying process through rapid drying, thereby enabling the production of a product that stably maintains the cross-sectional shape of the fiber.

[0113] Below, we will examine experimental examples of biodegradable filaments manufactured by the manufacturing method of the present invention.

[0114] For example, a filament was prepared from a high-viscosity polymer gel solution containing hyaluronic acid.

[0115] <Example 1>

[0116] According to a method for manufacturing a filament according to one embodiment of the present invention, a polymer is first dissolved in distilled water (DI Water) to prepare a solution. Here, a composition containing hyaluronic acid as the polymer is prepared. The hyaluronic acid content is provided at a concentration of 10% based on the weight of the polymer mixture.

[0117] <Comparative Example 1>

[0118] At this time, a solution was prepared in the same manner as in Example 1, except that 5 wt% of a functional agent was added to a mixture in a high-viscosity gel state.

[0119] <Comparative Example 2>

[0120] A solution was prepared in the same manner as in Example 1, except that 10 wt% of a functional agent was added to a mixture in a high-viscosity gel state.

[0121] <Comparative Example 3>

[0122] A solution was prepared in the same manner as in Example 1, except that 15 wt% of a functional agent was added to a mixture in a high-viscosity gel state.

[0123] <Experimental Example: Fiber Observation>

[0124] In the following, fibers prepared in the examples and comparative examples were observed. Specifically, hyaluronic acid filaments prepared by the method of the present invention were observed using SEM equipment.

[0125] (Experimental Example 1: Comparison of fiber surface morphology according to manufacturing conditions)

[0126] In Experimental Example 1, the speed or temperature at which the product solidifies can be controlled according to the manufacturing conditions, particularly the discharge amount (or spinning speed) of the solution.

[0127] division Discharge volume Heating temperature feed rate Heating and drying time First manufacturing condition 0.055g / min 50℃ 0.4m / min 88 seconds Second manufacturing condition 0.290g / min 120℃ 1.5 m / min 23.6 seconds

[0128] According to Table 1 above, the first manufacturing condition and the second manufacturing condition are shown. Under the first manufacturing condition and the second manufacturing condition, a molded article can be manufactured by spinning the solution according to <Example 1> at room temperature.

[0129] Under the first manufacturing condition, a molded product (first sample) can be manufactured by extruding a hyaluronic acid solution at an extrusion rate of 0.055 cc / min. According to the first manufacturing condition, the configuration of the spinning device used, for example, a 23G-1 inch needle, and the spinning distance, TCD (tip to collector distance), could be set to 200 mm. Then, spinning was carried out under room temperature conditions. The molded product manufactured in this way can be dried at a heating temperature of 50°C. The molded product can be transported by a heating roller at a transport speed of 0.4 m / min, and the heating time for solidifying the molded product can be maintained for at least 80 seconds. For example, it was heated for a heating time of 88 seconds. The sample was recovered from the surface of the heating roller using a surface winding method.

[0130] Under the second manufacturing condition, a molded product (second sample) can be manufactured by extruding the same solution at an output rate of 0.290 cc / min. According to the second manufacturing condition, the configuration of the spinning device is the same as in the first manufacturing condition, using a 23G-1 inch needle, and the spinning distance, TCD (tip to collector distance), can be set to 200 mm. Furthermore, spinning was carried out under room temperature conditions. The molded product manufactured in this way can be dried at a heating temperature of 120°C. That is, it is dried under conditions of a higher temperature than in the first manufacturing condition. The molded product can be transported by a heating roller at a transport speed of 1.5 m / min, and the heating time for solidification of the molded product can be set to 23.6 seconds. The sample was recovered from the surface of the heating roller using a surface winding method.

[0131] Figures 8 and 9 each show optical microscope images of hyaluronic acid filament samples prepared according to the first and second manufacturing conditions, respectively.

[0132] Referring to Fig. 8, it was confirmed that in the case of the filament produced under the first manufacturing conditions, the fiber surface of the first sample molded product showed a smooth shape.

[0133] Referring to Fig. 9, it was visually confirmed that in the case of the filament produced by the second manufacturing condition, the fiber surface of the second sample molded product was relatively rougher than that of the first sample molded product produced by the first manufacturing condition.

[0134] That is, according to the experimental example, in the case of the second manufacturing condition, as the discharge volume increases and the spinning speed increases, the conveying speed conveyed through each roller must be set quickly in the same environment. Accordingly, in the second manufacturing condition, the heating temperature was increased compared to the first manufacturing condition so that solidification could occur in response to the fast conveying speed.

[0135] As such, in this experimental example, changes in the surface of the sample according to manufacturing conditions could be observed, and it was confirmed that the surface smoothness of the product was excellent under manufacturing conditions where production was carried out at a low speed.

[0136] (Experimental Example 2: Comparison of changes in fiber shape and fiber diameter according to the amount of functional agent added)

[0137] In this experimental example, changes in fiber shape and fiber diameter were observed according to the amount of functional agent added. The functional agent may be a biodegradable polymer or a biocompatible polymer, and examples include collagen, alginic acid, PLA, and PGA. In this experimental example, alginic acid was included.

[0138] These are the results measured from hyaluronic acid filament samples prepared identically under either the first or second manufacturing conditions, using the respective mixture solutions according to the examples and comparative examples. In this example, the samples were prepared under the first manufacturing conditions.

[0139] FIG. 10 is a graph showing the fiber diameter size changed according to the amount of functional agent added for a filament product manufactured by a filament manufacturing method according to one embodiment of the present invention.

[0140] FIG. 11 is an image showing optical microscope photographs of filament products manufactured by a filament manufacturing method according to one embodiment of the present invention, showing different shapes depending on the amount of functional agent added.

[0141] Referring to the drawing, the diameter of the fiber of the filament prepared from the solution of Example 1 was measured to be approximately 120.8 μm.

[0142] In addition, it was confirmed that different diameters appeared from each sample depending on changes in the amount of functional agent added.

[0143] In the case of Sample A, in which 5% of alginate powder was added as a functional agent of Comparative Example 1, the fiber diameter of the filament was measured to be approximately 142.5 μm.

[0144] In the case of Sample B, which had 10% of the functional agent of Comparative Example 2 added, the fiber diameter of the filament was measured to be approximately 167.7 μm.

[0145] In the case of Sample C, which had 15% of the functional agent of Comparative Example 3 added, the fiber diameter of the filament was measured to be approximately 146.3 μm. The sample according to Comparative Example 3 had an additional functional agent added compared to Comparative Example 2, and it was confirmed that the fiber diameter decreased.

[0146] Thus, the filament produced by the manufacturing method of the present invention can be formed with a fiber diameter in the range of about 120 μm to 170 μm.

[0147] Referring to FIG. 11, FIG. 11 (A) illustrates the fiber shape (A) of sample A, FIG. 11 (B) illustrates the fiber shape (B) of sample B, and FIG. 11 (C) illustrates the fiber shape (C) of sample C. Here, by referring to the drawings, it can be seen that the fiber diameter size of sample B has increased by more than about 30% compared to sample A. When examining the fiber shape (B) of sample B, it was confirmed that the functional pharmaceutical substance is distributed within the product. In other words, it can be determined that the change in fiber diameter size is due to the functional pharmaceutical substance existing in the form of fine granules within the fiber, leading to a change in diameter.

[0148] In addition, in the case of Sample C, it can be seen that the fiber diameter actually decreased even with the addition of the drug. When examining the fiber shape (C) of Sample C, it can be confirmed that a relatively large amount of functional drug substances clumped together and separated from the hyaluronic acid polymer, existing as independent clumps. It can be determined that these clumping issues did not significantly contribute to the change in fiber diameter. In particular, not only were the functional drug substances clumped together, but the surface of the fiber itself was also found to be uneven. Through this, it was found that the functional drug substances existed separated into clumps within the fiber.

[0149] Accordingly, in order to manufacture a product containing a functional drug inside a hyaluronic acid polymer, it is considered desirable to form it within an addition amount of up to about 10%.

[0150] As described above, according to the filament manufacturing method of the present invention, a functional agent can be added to a hyaluronic acid solution to further enhance biocompatibility or perform other functions, and the functional agent powder can be included so that it is distributed in large quantities within the manufactured filament. In particular, the fiber diameter can be controlled differently as the functional agents exist in powder form within the filament.

[0151] The hyaluronic acid filament produced by the filament manufacturing apparatus and method of the present invention can be utilized as a medical scaffold. Here, the scaffold is a solid matrix called the Extracellular Matrix (ECM), and it is desirable that it be biocompatible. That is, there should be no rejection reaction with cells. In addition, architectural engineering features may be imparted. Accordingly, it can be formed into a porous and degradable structure. Furthermore, it is desirable that it possess bioactivity and be manufactured with a structure identical to the intrinsic mechanical properties of the host tissue. A medical scaffold is manufactured using the filament of the present invention.

[0152] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are for illustrative purposes only and are not intended to limit the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. Explanation of the symbols

[0153] 110: Radiation section 120: First drying section 130: 2nd Drying Section 140: Winding Section

Claims

Claim 1 A method for manufacturing a filament using a biodegradable polymer as a raw material, comprising: a solution preparation step of mixing a high-viscosity gel-state polymer mixture containing a biodegradable polymer including hyaluronic acid (HA) at a concentration of 5 w% or more and 20 w% or less based on the weight of the total solution without melting or heating by heat; a molding article preparation step of forming a fibrous molded article by compression spinning the polymer mixture at room temperature; and a molded article drying step of drying and curing the molded article, wherein the molded article drying step comprises: a conveying step of conveying the molded article in a state of contact and attachment to a rod-shaped heating roller with a heated surface, while rotating and conveying the molded article without stretching it to minimize shape deformation; a curing step of transferring heat to the molded article through direct contact via the heating roller; and a winding step of winding the molded article onto a winding roller and recovering it. Claim 2 In claim 1, the molding drying step further comprises a cooling step for cooling the molded product between the curing step and the winding step, wherein the cooling step winds the molded product transferred from the heating roller in a winding manner by means of a cooling roller at room temperature spaced apart from the heating roller and delivers it to the winding roller, and in the molding drying step, the heating roller comprises a first region which is a section where the molded product is first contacted and heated and dried, and a second region which is a low-gravity section where the molded product is heated and dried while hanging from the bottom due to the influence of gravity while rotating after the first region, a method for manufacturing a filament made of a biodegradable polymer as a raw material. Claim 3 A method for manufacturing a filament using a biodegradable polymer as a raw material, wherein the polymer mixture further comprises a functional agent at a concentration of 5 w% or more and 15 w% or less based on the weight of the total solution. Claim 4 A method for manufacturing a filament using a biodegradable polymer as a raw material, wherein, in the first step of manufacturing the molded article, the discharge amount of the mixture extruded is 0.05 to 0.5 g / min, in the step of drying the molded article, the heating temperature of the heating roller is 40℃ or higher and 150℃ or lower, and the conveying speed of the molded article by the rotation of the heating roller is 0.3 m / min or higher and 2.0 m / min or lower. Claim 5 An apparatus for manufacturing a filament using a biodegradable polymer as a raw material, utilizing a method for manufacturing a filament using a biodegradable polymer as a raw material according to claim 1, comprising: a spinning unit for forming a fibrous molded article by compressing and spinning a solution composed of a high-viscosity gel-state polymer mixture; a first drying unit for drying the molded article by transferring heat; a second drying unit for cooling the molded article; and a winding unit for recovering the molded article. Claim 6 In claim 5, the first drying unit comprises a heating roller that transfers heat generated internally to the surface, and is a filament manufacturing device using a biodegradable polymer as a raw material. Claim 7 In claim 6, the first drying unit is characterized in that the surface of the heating roller is coated with a hydrophobic polymer, thereby forming a filament manufacturing apparatus using a biodegradable polymer as a raw material. Claim 8 delete Claim 9 delete Claim 10 delete

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