PLA microparticle composition for dermal filler and production method therefor

Abstract

The present invention relates to a PLA microparticle composition for a dermal filler and a production method therefor. Provided are a PLA microparticle composition for a dermal filler, the composition being uniformly produced through micro-spraying by a chemical-resistant spray equipped with a brass nozzle, and a production method for PLA microparticles for a dermal filler, the method exhibiting a high yield, and thus same may be utilized in the skin plastic surgery filler production industry by having a cheaper and simpler production process.

Description

PLA microparticle composition for dermal filler and method for producing the same

[0001] The present invention relates to a PLA micro particle composition for dermal fillers and a method for producing the same, and more particularly, to a PLA (polylactic acid) micro particle composition for dermal fillers uniformly produced through fine spraying of a chemical-resistant spray equipped with a brass nozzle and a method for producing the same.

[0002] When soft tissue defects in the human skin occur due to external impact, disease, or aging, tissue augmentation, such as soft tissue augmentation, has been used for cosmetic or therapeutic purposes. This augmentation is performed surgically through plastic surgery, or non-surgically by injecting biological tissue or synthetic polymer chemicals into the affected area to increase and expand the volume of soft tissue, thereby restoring and correcting its shape. In this case, the substance similar to skin tissue is injected into a specific area to expand the soft tissue, thereby cosmetically increasing the volume of areas such as cheeks, lips, breasts, and buttocks, and the substance used for wrinkle improvement or contour correction by reducing fine and deep wrinkles in the skin is called a soft tissue augmentation material, commonly referred to as a dermal filler.

[0003] The most commonly used filler is hyaluronic acid. Hyaluronic acid is a component that exists in the human body, such as in joint fluid, cartilage, and skin. Hyaluronic acid fillers work by attracting water molecules around the treated skin to add volume and moisture. They not only add volume to the skin, but also help moisturize it, making them primarily used on the forehead, nose, under-eye area, aegyo-sal (cute sal), chin, and lips. However, hyaluronic acid fillers have a short lifespan of 3 to 12 months, so their effectiveness decreases over time, requiring regular treatments.

[0004] Poly-L-lactic acid (PLLA) fillers are biocompatible and biodegradable polymeric synthetic materials that serve as microsphere support. Biodegradable polymer microparticles like poly-L-lactic acid (PLLA) have recently attracted significant attention as tissue repair materials for facial and body applications. Biodegradable polymers do not contain any harmful substances and can degrade over a long period of time, typically six months to four years, making them suitable for a wide range of applications.

[0005] Spray drying and emulsification-solvent evaporation methods are used to manufacture biodegradable polymer microparticles. Polymer microparticles manufactured by spray drying may have a hollow center, have irregular particle shapes, or may aggregate with each other. The emulsification-solvent evaporation method is a method of manufacturing polymer microparticles by vigorously stirring a dispersion solution containing a polymer dissolved in an organic solvent and an emulsified solution containing a surfactant to form an emulsion and then evaporating the solvent. Because emulsions are thermodynamically unstable, the aqueous and organic phases tend to separate from each other through processes such as coalescence, fusion, and creaming, which requires strong stirring. As described above, because of this unstable state, it is difficult to maintain the emulsion for a long time.

[0006] Based on the above background technology, the inventors of the present invention have completed the present invention, which can manufacture a PLA micro-particle composition for dermal filler that is non-agglomerated and exhibits a high yield through a simple manufacturing process.

[0007] [Prior Art Literature]

[0008] (Patent Document) KR 10-1855878 B1 (May 2, 2018)

[0009] The purpose of the present invention is to provide a PLA fine particle composition for dermal filler, which comprises biodegradable polymers PLA (polylactic acid) and PVA (polyvinyl alcohol), and is characterized in that it is formed uniformly without agglomeration by fine spraying of a chemical-resistant spray equipped with a brass nozzle.

[0010] In addition, the purpose of the present invention is to provide a method for manufacturing PLA fine particles for dermal fillers, which are characterized in that they are formed uniformly without agglomeration by fine spraying of a chemical-resistant spray equipped with a brass nozzle, and which includes biodegradable polymers PLA (polylactic acid) and PVA (polyvinyl alcohol).

[0011] The technical problems to be solved by the invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0012] In order to solve the above problem, the present invention provides a PLA fine particle composition for dermal filler, which comprises biodegradable polymers PLA (polylactic acid) and PVA (polyvinyl alcohol), and is characterized in that it is formed uniformly without agglomeration by fine spraying of a chemical-resistant spray equipped with a brass nozzle.

[0013] In addition, the present invention provides a method for producing PLA microparticles for dermal fillers, comprising the steps of: preparing a PVA solution by mixing PVA (polyvinyl alcohol) and water; preparing a PLA solution by mixing PLA (polylactic acid) and DCM (dichloromethane); finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing with a homogenizer to produce a PLA emulsion; dispersing the PLA emulsion with a sonicator; removing DCM contained in the dispersed PLA emulsion; and drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles.

[0014] The method of finely spraying the PLA solution into the PVA solution is characterized in that the PLA solution is finely sprayed into the PVA solution for 2 to 4 minutes as particles having a size of 0.4 to 1.1 mm using a chemical-resistant sprayer equipped with a brass nozzle.

[0015] In addition, the present invention provides a method for producing PLA microparticles for dermal fillers, comprising the steps of: mixing PVA (polyvinyl alcohol) and water to produce a PVA solution; mixing a mixture of PLA (polylactic acid) and chloroform and DCM (dichloromethane) to produce a PLA solution; finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing with a homogenizer to produce a PLA emulsion; dispersing the PLA emulsion using a sonicator; removing DCM contained in the dispersed PLA emulsion; and drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles.

[0016] The above mixture of chloroform and DCM (dichloromethane) is characterized in that it is mixed in a volume ratio of 20:80.

[0017] By means of solving the above problem, the present invention provides a PLA microparticle composition for dermal fillers that is uniformly manufactured through fine spraying of a chemical-resistant spray equipped with a brass nozzle and a method for manufacturing PLA microparticles for dermal fillers with a high yield, thereby enabling use in the filler manufacturing industry for skin plastic surgery with a simple manufacturing process and low cost.

[0018] FIG. 1a and FIG. 1b are diagrams illustrating a method for manufacturing PLLA microparticles for dermal fillers using a chemical-resistant spray equipped with a brass nozzle according to a manufacturing example of the present invention and a method for manufacturing PLLA microparticles for dermal fillers using a syringe according to a comparative example of the present invention.

[0019] Figure 2 is an image showing the aggregation phenomenon of PLLA microparticles for dermal filler using a syringe manufactured according to a comparative example of the present invention.

[0020] Figure 3 is an image showing PLLA microparticles for dermal filler manufactured according to a manufacturing example of the present invention.

[0021] The terms used in this specification will be briefly explained, and the present invention will be described in detail.

[0022] The terms used in this invention have been selected from widely used, common terms, taking into account their functions. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Therefore, the terms used in this invention should be defined based on their meaning and the overall content of the invention, rather than simply their names.

[0023] When a part of a specification is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0024] Below, with reference to the attached drawings, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0025] Specific details, including the problems to be solved, means of solving them, and the effects of the invention, are included in the embodiments and drawings described below. The advantages and features of the present invention, and methods for achieving them, will become clearer with reference to the embodiments described below in detail, along with the accompanying drawings.

[0026] Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

[0027]

[0028] The present invention provides a PLA fine particle composition for dermal filler, which comprises biodegradable polymers, polylactic acid (PLA) and polyvinyl alcohol (PVA), and is characterized in that it is formed uniformly without agglomeration by fine spraying from a chemical-resistant spray equipped with a brass nozzle.

[0029] The above PVA may be included as a surfactant.

[0030] It is preferable that the above PLA is PLLA (poly-L-lactic acid) or PDLLA (poly-D,L-lactic acid).

[0031] The above PLA fine particles may have a size of 10 to 20 μm.

[0032]

[0033] In addition, the present invention provides a method for producing PLA microparticles for dermal fillers, comprising the steps of: preparing a PVA solution by mixing PVA (polyvinyl alcohol) and water; preparing a PLA solution by mixing PLA (polylactic acid) and DCM (dichloromethane); finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing with a homogenizer to produce a PLA emulsion; dispersing the PLA emulsion with a sonicator; removing DCM contained in the dispersed PLA emulsion; and drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles.

[0034] The above PVA may be included as a surfactant.

[0035] It is preferable that the above PLA is PLLA (poly-L-lactic acid) or PDLLA (poly-D,L-lactic acid).

[0036] The step of preparing the above PVA solution is preferably prepared by adding 2 to 4 g of PVA to 100 ml of water, but is more preferably prepared by adding 3 g of PVA to 100 ml of water.

[0037] The step of preparing the above PVA solution is preferably to mix the PVA and water by boiling them in an oil bath at a temperature of 85 to 95°C for 1 to 3 hours, but it is more preferable to mix the PVA and water by boiling them in an oil bath at a temperature of 90°C for 2 hours.

[0038] The step of preparing the above PVA solution may further include a step of mixing the PVA and water in a double boiler and then cooling them at room temperature.

[0039] The above PLA solution is preferably prepared by mixing the PLA and DCM to a concentration of 30 to 100 mg / mL, but it is more preferably prepared by mixing the PLA and DCM to a concentration of 60 mg / mL.

[0040] According to one embodiment of the present invention, the step of preparing the PLA solution by mixing the PLA and DCM may be such that the PLA solution is prepared by mixing 3 g of the PLA and 50 mL of the DCM.

[0041]

[0042] The step of preparing the above PLA solution may be performed by mixing the PLA and the DCM by stirring for 0.5 to 1.5 hours, but it is more preferable to mix the PLA and the DCM by stirring for 1 hour.

[0043] It is preferable to finely spray the PLA solution into the PVA solution using a chemical-resistant spray equipped with a brass nozzle to finely spray the PLA solution into the PVA solution in particles of 0.4 to 1.1 mm in size for 2 to 4 minutes, but it is more preferable to finely spray the PLA solution into the PVA solution in particles of 0.5 to 1 mm in size for 3 minutes using a chemical-resistant spray equipped with a brass nozzle.

[0044] The chemical-resistant spray equipped with the brass nozzle preferably includes a bottle made of chemical-resistant glass into which the PLA solution can be filled and sprayed.

[0045] The above chemical resistant spray may be corroded by the DCM during spraying of the PLA solution into the PVA solution when the brass nozzle and the chemical resistant glass bottle are not equipped, which may affect the formation of uniform PLA microparticles and may also affect the yield of PLA microparticles.

[0046] It is preferable that the mixing of the above homogenizer be performed by finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with the brass nozzle and mixing at 800 to 1000 rpm.

[0047] If the mixing of the above homogenizer is performed at a speed less than 800 rpm or more than 1000 rpm, the manufacturing process time may increase or the PLA microparticles may agglomerate, affecting the formation of uniform PLA microparticles and also affecting the yield of PLA microparticles.

[0048] It is preferable that the dispersion of the above sonicator disperses the cloudy PLA emulsion prepared by mixing of the above homogenizer into a clear PLA emulsion.

[0049] It is preferable to perform the dispersion of the above sonicator for 20 to 40 minutes, but it is more preferable to perform it for 30 minutes.

[0050] It is preferable to remove the above DCM by stirring in a fume hood for 2 to 4 hours, but it is more preferable to remove it by stirring in a fume hood for 3 hours.

[0051] It is preferable to dry the above PLA emulsion by diluting the concentrated PLA emulsion from which the DCM has been removed, filtering under reduced pressure, and drying.

[0052] The above drying method may include hot air drying, freeze drying, reduced pressure drying, vacuum drying, boiling drying or spray drying, and is preferably hot air drying using a dry oven, but is not limited thereto.

[0053] It is preferable that the above fine particles are formed uniformly without agglomeration by finely spraying the PLA solution with a chemical-resistant spray equipped with the brass nozzle.

[0054] It is preferable that the above PLA microparticles are produced at a yield of 40 to 60%.

[0055] The above PLA fine particles may have a size of 10 to 20 μm.

[0056] The above PLA fine particles may be in powder form.

[0057]

[0058] In addition, the present invention provides a method for producing PLA microparticles for dermal fillers, comprising the steps of: mixing PVA (polyvinyl alcohol) and water to produce a PVA solution; mixing a mixture of PLA (polylactic acid) and chloroform and DCM (dichloromethane) to produce a PLA solution; finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing with a homogenizer to produce a PLA emulsion; dispersing the PLA emulsion using a sonicator; removing DCM contained in the dispersed PLA emulsion; and drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles.

[0059] The above PVA may be included as a surfactant.

[0060] It is preferable that the above PLA is PLLA (poly-L-lactic acid) or PDLLA (poly-D,L-lactic acid).

[0061] The step of preparing the above PVA solution is preferably prepared by adding 2 to 4 g of the PVA to 100 ml of water, but is more preferably prepared by adding 3 g of the PVA to 100 ml of water.

[0062] The step of preparing the above PVA solution is preferably to mix the PVA and water by boiling them in an oil bath at a temperature of 85 to 95°C for 1 to 3 hours, but it is more preferable to mix the PVA and water by boiling them in an oil bath at a temperature of 90°C for 2 hours.

[0063] The step of preparing the above PVA solution may further include a step of mixing the PVA and water in a double boiler and then cooling them at room temperature.

[0064] The above PLA solution is preferably prepared by mixing the PLA and the mixture of chloroform and DCM at a concentration of 30 to 100 mg / mL, but is more preferably prepared by mixing the PLA and the mixture of chloroform and DCM at a concentration of 60 mg / mL.

[0065] It is preferable that the above mixture of chloroform and DCM be mixed in a volume ratio of 20:80.

[0066] According to another embodiment of the present invention, in the step of preparing a PLA solution by mixing a mixture of PLA and chloroform and DCM, the PLA solution can be prepared by mixing 50 ml of a mixture of 12.5 mL of the chloroform and 37.5 mL of the DCM and 3 g of the PLA.

[0067]

[0068] The step of preparing the above PLA solution may be performed by stirring and mixing the PLA and the mixture of chloroform and DCM for 0.5 to 1.5 hours, but it is more preferable to stir and mix the PLA and the mixture of chloroform and DCM for 1 hour.

[0069] It is preferable to finely spray the PLA solution into the PVA solution using a chemical-resistant spray equipped with the brass nozzle to finely spray the PLA solution into the PVA solution in particles of 0.4 to 1.1 mm in size for 2 to 4 minutes, but it is more preferable to finely spray the PLA solution into the PVA solution in particles of 0.5 to 1 mm in size for 3 minutes using the chemical-resistant spray equipped with the brass nozzle.

[0070] The chemical-resistant spray equipped with the brass nozzle preferably includes a bottle made of chemical-resistant glass into which the PLA solution can be filled and sprayed.

[0071] The above chemical resistant spray may be corroded by the DCM during spraying of the PLA solution into the PVA solution when the brass nozzle and the chemical resistant glass bottle are not equipped, which may affect the formation of uniform PLA microparticles and may also affect the yield of PLA microparticles.

[0072] It is preferable that the mixing of the above homogenizer be performed by finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with the brass nozzle and mixing at 800 to 1000 rpm.

[0073] If the mixing of the above homogenizer is performed at a speed less than 800 rpm or more than 1000 rpm, the manufacturing process time may increase or the PLA microparticles may agglomerate, affecting the formation of uniform PLA microparticles and also affecting the yield of PLA microparticles.

[0074] It is preferable that the dispersion of the above sonicator disperses the cloudy PLA emulsion prepared by mixing of the above homogenizer into a clear PLA emulsion.

[0075] It is preferable to perform the dispersion of the above sonicator for 20 to 40 minutes, but it is more preferable to perform it for 30 minutes.

[0076] It is preferable to remove the above DCM by stirring in a fume hood for 2 to 4 hours, but it is more preferable to remove it by stirring in a fume hood for 3 hours.

[0077] It is preferable to dry the above PLA emulsion by diluting the concentrated PLA emulsion from which the DCM has been removed, filtering under reduced pressure, and drying.

[0078] The above drying method may include hot air drying, freeze drying, reduced pressure drying, vacuum drying, boiling drying or spray drying, and is preferably hot air drying using a dry oven, but is not limited thereto.

[0079] It is preferable that the above fine particles are formed uniformly without agglomeration by finely spraying the PLA solution with a chemical-resistant spray equipped with the brass nozzle.

[0080] The above PLA fine particles may be in powder form.

[0081]

[0082] Hereinafter, to aid understanding of the present invention, examples will be given in detail. However, the following examples are intended only to illustrate the scope of the present invention and are not intended to limit its scope. These examples are provided to more fully explain the present invention to those of average skill in the art.

[0083]

[0084] <Manufacturing Example>

[0085] 1-1. Manufacturing of PLLA microparticles for dermal filler using a sprayer equipped with a brass nozzle Ⅰ

[0086] Mix 3 g of PVA (polyvinyl alcohol) and 100 mL of water, and boil in an oil bath at 90°C for 2 hours while stirring to prepare a PVA solution, and then cool to room temperature. In addition, mix 3 g of PLLA (poly-L-lactic acid) and 50 mL of DCM (dichloromethane) for 1 hour to prepare a PLLA solution. Put the prepared PVA solution into a 400 mL beaker, attach a homogenizer, stir at 800 to 900 rpm, and put the prepared PLLA solution into a chemical-resistant spray equipped with a brass nozzle. Using the chemical-resistant spray equipped with a brass nozzle, add the PLLA solution to the stirred PVA solution and spray finely into 0.5 to 1 mm droplets for 3 minutes to prepare a cloudy PLLA emulsion. Afterwards, the cloudy PLLA emulsion is dispersed into a clear PLLA emulsion in a sonicator for 30 minutes, and DCM is removed for 3 hours while stirring in a fume hood. The PLLA emulsion from which DCM has been removed is diluted with water, filtered under reduced pressure for 3 hours, and the filtered filter paper is dried for 15 to 20 minutes to obtain PLLA fine particles (method using a spray in Fig. 1a).

[0087] 1-2. Manufacturing of PLLA microparticles for dermal filler using a sprayer equipped with a brass nozzle II

[0088] Mix 3 g of PVA (polyvinyl alcohol) and 100 mL of water, and boil in an oil bath at 90°C for 2 hours while stirring to prepare a PVA solution, and then cool to room temperature. In addition, mix 3 g of PLLA (poly-L-lactic acid) and 50 mL of a mixture of chloroform and DCM (12.5 mL of chloroform + 37.5 mL of DCM) for 1 hour to prepare a PLLA solution. Put the prepared PVA solution into a 400 mL beaker, attach a homogenizer, stir at 800 to 900 rpm, and put the prepared PLLA solution into a chemical-resistant spray equipped with a brass nozzle. Using the chemical-resistant spray equipped with a brass nozzle, add the PLLA solution to the stirred PVA solution and spray finely into 0.5 to 1 mm droplets for 3 minutes to prepare a cloudy PLLA emulsion. Afterwards, the cloudy PLLA emulsion is dispersed into a clear PLLA emulsion in a sonicator for 30 minutes, and DCM is removed for 3 hours while stirring in a fume hood. The PLLA emulsion from which DCM has been removed is diluted with water, filtered under reduced pressure for 3 hours, and the filtered filter paper is dried for 15 to 20 minutes to obtain PLLA fine particles (method using a spray in Fig. 1a).

[0089]

[0090] <Example>

[0091] In order to evaluate the yield of PLLA microparticles using a sprayer equipped with a brass nozzle, the same process as the above manufacturing example was used, but the composition was prepared as shown in Table 1 below and evaluated.

[0092]

[0093] Example 1Example 2Example 3Mixed formSpraySpraySprayWeight of solid PLLA (g)338Volume of DCM solvent (ml)5050200Weight of solid PVA (g)3320Volume of water (ml)100100500Homogenizer speed (rpm)900800800

[0094]

[0095] <Comparative Example>

[0096] In order to evaluate the yield of PLLA fine particles using a sprayer equipped with a brass nozzle, the PLLA solution prepared was put into a syringe and finely sprayed into a stirred PVA solution in a size of 2 mm for 15 minutes to prepare a cloudy PLLA emulsion, as in the method using a syringe in Fig. 1b, and the process was the same as the above manufacturing example, but it was prepared with the composition shown in Table 2 below.

[0097]

[0098] Comparative Example 1Comparative Example 2Comparative Example 3Mixed formSyrringeSyrringeSyringerWeight of solid PLLA (g)133Volume of DCM solvent (ml)105050Weight of solid PVA (g)423Volume of water (ml)100100100Homogenizer speed (rpm)180015001500

[0099]

[0100] <Experimental Example 1> Yield evaluation of PLLA microparticles manufactured using a sprayer equipped with a brass nozzle

[0101] The yield of PLLA microparticles was evaluated by manufacturing them as in the above examples and comparative examples. As shown in Table 3, it was confirmed that the yield of PLLA microparticles manufactured by the spraying method using a sprayer equipped with a brass nozzle, which is an example, was 40 to 50%, and thus it was confirmed that it showed a much higher yield than the PLLA microparticles manufactured using a syringe, which is a comparative example.

[0102] This is because, among the methods using syringes of Comparative Examples 1 to 3, when the PLLA solution is injected into the PVA solution using a syringe, the PLLA solution droplets are injected at 2 mm, which is larger than the PLLA solution droplets of 0.5 to 1 mm in size when injected using the spray method, and the time for injecting into the PVA solution is longer than the method using the spray method, so as shown in Fig. 2, the particles of the PLLA emulsion are aggregated and not uniform, and the yield is lowered due to the need for multiple filtrations.

[0103] Additionally, examples with relatively low homogenizer speeds showed higher yields than comparative examples, indicating that the yield of PLLA microparticles is affected by the homogenizer speed. This is because if the speed is too high, the PLLA microparticles aggregate, affecting the yield. Therefore, the yield can be increased only when the homogenizer is stirred at a low speed to prevent bubbles.

[0104]

[0105] Yield (g)Yield Percentage (%)Example 11.5050Example 21.3846Example 33.3642Comparative Example 10.110Comparative Example 20.520Comparative Example 31.137

[0106]

[0107] <Experimental Example 2> Distribution of PLLA microparticles manufactured using a sprayer equipped with a brass nozzle

[0108] PLLA microparticles manufactured using the same method as the above manufacturing example were analyzed using a scanning electron microscope (SEM). As shown in Fig. 3, it was confirmed that the particles were manufactured uniformly without agglomeration.

[0109]

[0110] As shown in the above experimental examples, it can be seen that the method for manufacturing PLLA microparticles using a spray equipped with the brass nozzle is an excellent invention that can overcome damage to the syringe due to organic solvent and low yield due to agglomeration of PLLA when manufacturing PLLA microparticles using a syringe.

[0111]

[0112] While specific aspects of the present invention have been described in detail above, it should be apparent to those skilled in the art that these specific descriptions are merely preferred implementation examples and are not intended to limit the scope of the present invention. Therefore, the actual scope of the present invention is defined by the appended claims and their equivalents. The scope of the present invention is set forth in the claims below, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims

1. Contains biodegradable polymers PLA (polylactic acid) and PVA (polyvinyl alcohol). A PLA fine particle composition for dermal filler characterized in that it is formed uniformly without agglomeration by fine spraying of a chemical-resistant spray equipped with a brass nozzle.

2. A step of preparing a PVA solution by mixing PVA (polyvinyl alcohol) and water; A step of preparing a PLA solution by mixing PLA (polylactic acid) and DCM (dichloromethane); A step of finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing using a homogenizer to prepare a PLA emulsion; A step of dispersing the above PLA emulsion using a sonicator; A step of removing DCM contained in the above dispersed PLA emulsion; and A method for producing PLA microparticles for dermal fillers, comprising: a step of drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles; 3. In paragraph 2, A method for producing PLA microparticles for dermal fillers, characterized in that the PLA solution is micro-sprayed into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle to form particles having a size of 0.4 to 1.1 mm for 2 to 4 minutes.

4. A step of preparing a PVA solution by mixing PVA (polyvinyl alcohol) and water; a step of preparing a PLA solution by mixing PLA (polylactic acid) and a mixture of chloroform and DCM (dichloromethane); A step of finely spraying the PLA solution into the PVA solution using a chemical-resistant sprayer equipped with a brass nozzle and mixing using a homogenizer to prepare a PLA emulsion; A step of dispersing the above PLA emulsion using a sonicator; A step of removing DCM contained in the above dispersed PLA emulsion; and A method for producing PLA microparticles for dermal fillers, comprising: a step of drying the PLA emulsion from which the DCM has been removed to obtain PLA microparticles; 5. In paragraph 4, A method for manufacturing PLA microparticles for dermal filler, characterized in that the above mixture of chloroform and DCM (dichloromethane) is mixed in a volume ratio of 20:80.

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