Manufacturing method for eugenol-incorporated fragrance microcapsule composed of polyhydroalkanoates

Abstract

The present invention relates to a manufacturing method for a eugenol-incorporated fragrance microcapsule composed of polyhydroalkanoates and, more specifically, to a manufacturing method for manufacturing a polyhydroxyalkanoate fragrance microcapsule by using water-in-oil-in-water (W1 / O / W2) multiple emulsion.

Description

Method for manufacturing eugenol fragrance capsules using polyhydroxyalkanoate

[0001] The present invention relates to a method for manufacturing a eugenol fragrance capsule using polyhydroxyalkanoate, and relates to a method for manufacturing a polyhydroxyalkanoate fragrance capsule using a W1 / O / W2 (Water-in-oil-in-water) multiple emulsion method.

[0002]

[0003] A fragrance capsule is a capsule containing a fragrant substance. Its purpose varies depending on the application, but it is generally used to physically and chemically protect and isolate the active substance from the external environment to block or conceal taste, smell, etc., control release characteristics to allow for sustained release, or change the properties of the active substance to make it easier to handle.

[0004] A variety of wall materials are used to produce these fragrance capsules, including melamine formaldehyde, polyethylene, and polypropylene. However, the nature of the manufacturing and use of these fragrance capsules is known to introduce microplastics into the environment, causing problems. As awareness of the environmental impact of microplastics grows, demand for biodegradable fragrance capsules is increasing. Therefore, research is being conducted on fragrance capsules made of biodegradable polymers to reduce microplastics in the environment. Representative examples of biodegradable polymers include thermoplastic starch and polylactic acid (PLA).

[0005] Polyhydroxyalkanoate (PHA), used in the present invention, is defined as a representative biodegradable polymer synthesized within microorganisms for carbon and energy storage. While polylactic acid (PLA), a widely used biodegradable plastic, requires specific processes to decompose, PHA is characterized by decomposition in most environments and is attracting attention as the only material that biodegrades even in the ocean. Against this backdrop, research was conducted on fragrance capsules utilizing polyhydroxyalkanoate, a type of biodegradable polymer, as a capsule material.

[0006]

[0007] The present invention has been devised to solve the above problems, and the purpose of the present invention is to provide a eugenol fragrance capsule using PHA, a biodegradable polymer, as a fragrance capsule instead of polylactic acid (PLA), a general fragrance biodegradable plastic.

[0008] 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.

[0009]

[0010] The method for manufacturing eugenol fragrance capsules using polyhydroxyalkanoate according to the present invention is as follows:

[0011] A step for preparing a fragrance mixture solution by preparing an HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution and then adding a fragrance to the prepared HP-β-CD aqueous solution;

[0012] A fragrance aqueous solution solubilization step in which the above fragrance mixture is solubilized by ultrasonic treatment to encapsulate the poorly soluble eugenol using the HP-β-CD aqueous solution;

[0013] A first W1 / O (Water-in-oil) emulsion manufacturing step in which polyhydroxyalkanoate (PHA) is dissolved in dichloromethane (DCM) and then mixed with the solubilized fragrance aqueous solution manufactured in the solubilization step;

[0014] A second W1 / O / W2 (Water-in-oil-in-water) emulsion manufacturing step of mixing the above first W1 / O (Water-in-oil) emulsion and a polyvinyl alcohol (PVA) aqueous solution and then homogenizing them;

[0015] It is characterized by including a fragrance capsule manufacturing step of manufacturing a microsphere suspension containing a fragrance component by stirring the above-manufactured secondary W1 / O / W2 (Water-in-oil-in-water) emulsion and evaporating the solvent.

[0016] In addition, the present invention is characterized in that it manufactures a eugenol fragrance capsule using polyhydroxyalkanoate by a method for manufacturing a eugenol fragrance capsule using polyhydroxyalkanoate.

[0017]

[0018] By means of solving the above problem, the present invention can manufacture fragrance capsules that are decomposed in most environments and biodegradable in the sea by applying PHA as fragrance capsules instead of using polylactic acid (PLA) that must go through a specific process.

[0019]

[0020] Figure 1 is a flow chart showing a method for manufacturing a eugenol fragrance capsule using the polyhydroxyalkanoate of the present invention.

[0021] Figure 2 is a calibration curve of the HPLC results of the W1 / O / W2 (Water-in-oil-in-water) multiple emulsion eugenol standard material according to an embodiment of the present invention.

[0022] Figure 3 is an HPLC chromatogram of eugenol standard material eugenol according to an embodiment of the present invention.

[0023] Figure 4 is a particle size analysis result of a fragrance capsule containing a fragrance component according to an embodiment of the present invention.

[0024] Figure 5 is a particle size analysis result of a fragrance capsule that does not contain a fragrance component according to an embodiment of the present invention.

[0025] Figure 6 is a scanning electron microscope photograph of a fragrance capsule containing a fragrance component according to an embodiment of the present invention.

[0026] Figure 7 is a scanning electron microscope photograph of a fragrance capsule that does not contain a fragrance component according to an embodiment of the present invention.

[0027] FIG. 8 is an FT-IR spectrum of (A): PHA, (B): HP-β-CD, (C): eugenol, (D): eugenol-HP-β-CD complex, (E): fragrance capsule containing fragrance component, (F): fragrance capsule not containing fragrance component, according to an embodiment of the present invention.

[0028]

[0029] The terms used in this specification will be briefly explained, and the present invention will be described in detail.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

[0035]

[0036] The method for manufacturing eugenol fragrance capsules using polyhydroxyalkanoate according to the present invention is performed by the following steps as shown in Fig. 1.

[0037] First, step 1 (S10) is a step for preparing a fragrance mixture. In step 1 (S10), a HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution is prepared, and then a fragrance is added to the prepared HP-β-CD aqueous solution.

[0038] In the above first step (S10), the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution is prepared at a concentration of 200 to 300 mM. If the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution is prepared at a concentration of less than 200 mM, it may be difficult to encapsulate poorly soluble eugenol, and if the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution is prepared at a concentration exceeding 300 mM, the molar concentration ratio with eugenol may not be correct, increasing the ultrasonic treatment time. Therefore, it is preferable to perform the process under the above conditions.

[0039] In the above first step (S10), the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution and the fragrance are added at a molar concentration ratio of 3:2. If added outside the above molar concentration ratio, the inclusion of eugenol may be difficult, and the sonication time and temperature may change, which may reduce efficiency, so it is preferable to perform the process under the above conditions.

[0040]

[0041] Next, the second step (S20) is a solubilization step of a fragrance aqueous solution. In the second step (S20), the fragrance mixture is sonicated to solubilize the poorly soluble eugenol by encapsulating it with the HP-β-CD aqueous solution.

[0042] In the second step (S20), the sonication is performed at 45 to 55°C for 55 to 65 minutes in the solubilization step of the fragrance aqueous solution. More preferably, it is performed at 50°C for 60 minutes. If the sonication is performed at less than 45°C or less than 55 minutes, the solubilization effect of the eugenol is minimal, and if the sonication is performed at more than 55°C or more than 65 minutes, there is a risk of deterioration of the eugenol and HP-β-CD aqueous solution, so it is preferable to perform the process under the above conditions.

[0043] Next, the third step (S30) is the first W1 / O (Water-in-oil) emulsion manufacturing step. The third step (S30) is manufactured by dissolving polyhydroxyalkanoate (PHA) in dichloromethane (DCM), and then mixing it with the solubilized fragrance aqueous solution manufactured in the solubilization step.

[0044] The above polyhydroxyalkanoate (PHA) is prepared by dissolving 160 mg (density 1.25 g / cm3) in 4 mL (density 1.33 g / cm3) of dichloromethane (DCM).

[0045] In the third step (S30), the mixing is performed using a probe sonicator for 1 to 3 minutes. More specifically, the solubilized fragrance aqueous solution prepared in the solubilization step is mixed using a 120 W probe sonicator for 2 minutes.

[0046]

[0047] Next, the fourth step (S40) is a step for producing a secondary W1 / O / W2 (Water-in-oil-in-water) emulsion. In the fourth step (S40), the primary W1 / O (Water-in-oil) emulsion and a polyvinyl alcohol (PVA) aqueous solution are mixed, and then homogenized to produce a secondary W1 / O / W2 (Water-in-oil-in-water) emulsion.

[0048] In the fourth step (S40), the homogenization is performed using a homogenizer at 13,000 to 14,000 rpm for 3 to 8 minutes. More specifically, the first W1 / O (Water-in-oil) emulsion and a 5% (W / V) polyvinyl alcohol (PVA) aqueous solution are mixed, and then homogenized using a homogenizer at 13,500 rpm for 5 minutes to produce a second W1 / O / W2 (Water-in-oil-in-water) emulsion.

[0049]

[0050] Next, the fifth step (S50) is a step for manufacturing a fragrance capsule. In the fifth step (S50), the manufactured secondary W1 / O / W2 (Water-in-oil-in-water) emulsion is stirred and the solvent is evaporated to manufacture a microsphere suspension containing a fragrance component.

[0051] In the fifth step (S50), the manufactured secondary W1 / O / W2 (Water-in-oil-in-water) emulsion is stirred at 400 to 600 rpm for 2 to 4 hours. More specifically, the manufactured secondary W1 / O / W2 (Water-in-oil-in-water) emulsion is stirred at 500 rpm for 3 hours under a fume hood to produce a microsphere suspension containing a fragrance component.

[0052]

[0053] In addition, the present invention is characterized in that it manufactures a eugenol fragrance capsule using polyhydroxyalkanoate by a method for manufacturing a eugenol fragrance capsule using polyhydroxyalkanoate.

[0054] The fragrance encapsulation rate of the above fragrance capsule is 9 to 11%.

[0055] As a result, the present invention can dramatically increase the encapsulation rate by utilizing W1 / O / W2 (Water-in-Oil-in-Water) double emulsification and HP-β-CD (2-Hydroxypropyl-β-cyclodextrin). In the past, the fragrance encapsulation rate was less than 0.19%, but the fragrance encapsulation rate of the present invention can be improved to 9 to 11% in fragrance capsules.

[0056] Conventional single-emulsion oil-in-water (O / W) emulsions have found it extremely difficult to encapsulate volatile chemicals using solvent evaporation. This has led to problems such as the fragrance components evaporating during the manufacturing process or failing to dissolve in aqueous solutions. The eugenol fragrance capsules using polyhydroxyalkanoate of the present invention have the effect of increasing the encapsulation rate through the aforementioned method.

[0057] Additionally, the average diameter of the fragrance capsules is 3.0 to 3.5 μm. The average diameter of the fragrance capsules can be confirmed in the experimental example below.

[0058]

[0059] Hereinafter, the present invention will be described in more detail through comparative examples and experimental examples manufactured using conventional methods. The objectives, features, and advantages of the present invention will be readily understood through the following examples. The present invention is not limited to the examples described herein and may be embodied in other forms. The examples introduced herein are provided to ensure that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Therefore, the present invention should not be limited by the following examples.

[0060]

[0061] Example 1: Preparation of a fragrance mixture and solubilization of a fragrance aqueous solution.

[0062] After preparing an aqueous solution of HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) at a concentration of 250 mM, a molar ratio of HP-β-CD: fragrance (3:2) is added (eugenol: 27.37 mg). Then, the solution is sonicated at 50°C for 60 minutes using a sonication bath (Powersonic420, Korea, Hwasin Tech) to encapsulate poorly soluble eugenol using HP-β-CD and solubilize it in the aqueous solution.

[0063]

[0064] Example 2: Preparation of primary W1 / O (water-in-oil) emulsion

[0065] 160 mg of PHA (Polyhydroxyalkanoate) was dissolved in 4 mL of DCM (Dichloromethane), and then mixed with the previously prepared solution to prepare a primary W1 / O (Water-in-oil) emulsion using a probe sonicator (Scientz-iid, NingBoScientz Biotechnology, China) at 120 W for 2 minutes.

[0066]

[0067] Example 3: Preparation of secondary W1 / O / W2 (water-in-oil-in-water) emulsion

[0068] After mixing the previously manufactured primary W1 / O emulsion with a 5% (W / V) PVA (Polyvinyl alcohol) aqueous solution, a secondary W1 / O / W2 (Water-in-oil-in-water) emulsion is manufactured by homogenizing the mixture using a homogenizer (HG-15G, DAIHAN Scientific, Korea) at 13,500 rpm for 5 minutes.

[0069]

[0070] Example 4: Preparation of fragrance capsules

[0071] To evaporate the solvent, the prepared W1 / O / W2 emulsion was stirred at 500 rpm for 3 hours under a fume hood to prepare a microsphere suspension containing fragrance components.

[0072]

[0073] [Experimental Example 1] Measurement of the encapsulation rate of fragrance capsules

[0074] The fragrance capsule suspension was prepared by centrifuging at 2000 xg for 30 minutes using a high-speed centrifuge (1580R, Labogene, Denmark), dissolving the precipitated pellet in dimethyl sulfoxide (DMSO), and then filtering.

[0075] The fragrance content of the fragrance capsules was quantified using high performance liquid chromatography (HPLC) (Agilent 1100 series, Agilent, USA) equipped with a UV DAD (Ultraviolet Diode Array Detector) under the following conditions.

[0076] The column used was an ODS (Octa-decyl Silica) column (150 mm x 4.6 mm, 5 μm). The column oven temperature was set to 40 °C, the sample injection volume was set to 20 μL, and the analysis was performed at 280 nm. The mobile phase was a 50:50 mixture of triple-distilled water and HPLC-grade ACN (Acetonitrile) at a flow rate of 1 mL / min. Eugenol was used as a standard. The analytical data were collected through Agilent OpenLab ChemStation. The encapsulation ratio of the fragrance was calculated using the following formula.

[0077]

[0078] [Formula 1]

[0079] Encapsulation Efficiency% (EE%) = A / BX 100

[0080] (Here, A is the total amount of the encapsulated material and B is the total amount of the material administered during manufacturing)

[0081]

[0082] Figure 2 is a calibration curve of the HPLC results of the W1 / O / W2 multi-emulsion method eugenol standard material, and Figure 3 is an HPLC chromatogram of the eugenol standard material eugenol.

[0083] Table 1 shows the results of quantitative analysis of eugenol from the HPLC of the W1 / O / W2 multi-emulsion method fragrance capsules, and Table 2 shows the results of quantitative analysis of eugenol from the HPLC of the O / W multi-emulsion method fragrance capsules.

[0084] Sample NameArea (mAU*S)Concentration (μg / mL)Eugenol Standard 19.69E+03500Eugenol Standard 24874.39250Eugenol Standard 32447.794125Eugenol Standard 41229.84262.5Eugenol Standard 5616.872931.25Eugenol Standard 6317.112315.625Eugenol Standard 7164.07877.8125Eugenol Standard 880.91653.90625Standard Curve = 19.36473x+16.14676 (R^2 = 0.9999)Sample NameArea (mAU*S)Calculated Concentration (μg / mL)Sample Sample 11087.68355.334 Sample 21098.09355.872 Sample 31053.05653.546 Average 1079.611 (±23.579) 54.918 (±1.217) Fragrance capsule fragrance encapsulation rate 10.0 (±0.22)%

[0085] Sample NameArea (mAU*S)Concentration (μg / mL)Eugenol Standard 15232.7250Eugenol Standard 22622.3125Eugenol Standard 31323.362.5Eugenol Standard 4660.831.25Eugenol Standard 5301.715.625Eugenol Standard 6124.77.8125Eugenol Standard 761.43.90625Eugenol Standard 831.81.953125Eugenol Standard 917.50.976563Standard Curve = 21.019x-12.533 (R^2 = 0.9999)Sample NameArea (mAU*S)Calculated Concentration (μg / mL)Sample 150.50.158 samples 234.60.118 samples 353.20.165 samples Average 46.1 (±10.050) 0.147 (±0.025) Fragrance capsule fragrance encapsulation rate 0.19 (±0.025)%

[0086] As shown in Table 1, the fragrance encapsulation rate of the fragrance capsules manufactured using the W1 / O / W2 multiple emulsion method was 10.0±0.22%. On the other hand, as shown in Table 2, when the fragrance capsules were manufactured using the primary O / W emulsion method, the fragrance encapsulation rate of the formulation was 0.19±0.025%, which indicates that the volatile fragrance evaporates during the process of evaporating the organic solvent for formulation, leaving only a very small amount of fragrance in the final product. Therefore, it can be seen that the W1 / O / W2 multiple emulsion method can effectively prevent the evaporation of the fragrance during the process of evaporating the organic solvent for formulation.

[0087]

[0088] [Experimental Example 2] Analysis of particle size distribution of fragrance capsules

[0089] The fragrance capsule suspension was centrifuged at 2000 xg for 30 minutes using a high-speed centrifuge, and the precipitated pellet was resuspended in 5 mL of purified water to prepare a sample.

[0090] The prepared sample was dispersed in water and the particle size and distribution were measured under ultrasonic treatment using a wet measurement of a particle size analyzer (PSA 990, Anton Parr, Austria).

[0091] Figure 4 shows the results of particle size analysis of a fragrance capsule containing a fragrance component, and Figure 5 shows the results of particle size analysis of a fragrance capsule not containing a fragrance component.

[0092]

[0093] As a result, as shown in Fig. 4, it was confirmed that the average diameter of the fragrance capsules including the fragrance component was 3.17±0.11 μm, and most of the particles were distributed within the size range of 1.19±0.02 μm to 5.14±0.31 μm. In addition, as shown in Fig. 5, it was confirmed that the average diameter of the fragrance capsules manufactured excluding the fragrance component was 3.17±0.11 μm, and most of the particles were distributed within the size range of 1.22±0.02 μm to 5.14±0.31 μm.

[0094]

[0095] [Experimental Example 3] Analysis of the Appearance of Fragrance Capsules

[0096] The fragrance capsule suspension was prepared in powder form using a freeze dryer (TFD5503, ilShinBioBase, Korea), coated with PtPd, and observed using a field emission scanning electron microscope (FT-SEM) (S-4300SE, HITACHI, Japan). Figure 6 is a scanning electron microscope photograph of a fragrance capsule containing a fragrance component, and Figure 7 is a scanning electron microscope photograph of a fragrance capsule not containing a fragrance component.

[0097] As a result, it was confirmed that spherical fragrance capsules were formed regardless of the presence or absence of fragrance, and the particle size was confirmed to be 1 to 5 μm.

[0098]

[0099] [Experimental Example 4] Fourier Transform Infrared (FT-IR) Analysis of Fragrance Capsules

[0100] The sample prepared in powder form using a freeze dryer was analyzed in reflection mode (ATR, attenuated total reflection) using an FT-IR spectrometer (ALPHA II, Bruker, USA).

[0101] Referring to Figure 8, the C=C Stretching peak (1510.14 cm) in (C) -1 ) was observed. This was attributed to the aromatic ring of eugenol, and the corresponding peak was not observed in (B) and (A).

[0102] 1514.62 cm from (D) -1 Through the peak, the eugenol and HP-β-CD inclusion complex was formed, and the C=C Stretching peak was 1510.14 cm -1 1514.62 cm in -1 You can see that it has moved.

[0103] In the FT-IR spectra of the fragrance capsules containing fragrance ingredients in (F) and (E), only the C=C Stretching peak (1513.87 cm) was observed. -1 ) It can be seen that the fragrance capsule containing the fragrance component manufactured by observing the fragrance component contained the fragrance component encapsulated in HP-β-CD.

[0104]

[0105] By means of solving the above problem, the present invention can manufacture fragrance capsules that are decomposed in most environments and biodegradable in the sea by applying PHA as fragrance capsules instead of using polylactic acid (PLA) that must go through a specific process.

[0106]

[0107] In this way, it will be understood by those skilled in the art that the technical configuration of the present invention described above can be implemented in other specific forms without changing the technical idea or essential features of the present invention.

[0108] Therefore, the embodiments described above should be understood as being exemplary and not restrictive in all respects, and the scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. A step for preparing a fragrance mixture solution by preparing an HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution and then adding a fragrance to the prepared HP-β-CD aqueous solution; A fragrance aqueous solution solubilization step in which the above fragrance mixture is solubilized by ultrasonic treatment to encapsulate the poorly soluble eugenol using the HP-β-CD aqueous solution; A first W1 / O (Water-in-oil) emulsion manufacturing step in which polyhydroxyalkanoate (PHA) is dissolved in dichloromethane (DCM) and then mixed with the solubilized fragrance aqueous solution manufactured in the solubilization step; A second W1 / O / W2 (Water-in-oil-in-water) emulsion manufacturing step of mixing the above first W1 / O (Water-in-oil) emulsion and a polyvinyl alcohol (PVA) aqueous solution and then homogenizing them; A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that it comprises a step of producing a fragrance capsule by stirring the above-produced secondary W1 / O / W2 (Water-in-oil-in-water) emulsion and evaporating the solvent to produce a microsphere suspension containing a fragrance component.

2. In paragraph 1, A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that in the above fragrance mixture production step, the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution is produced at a concentration of 200 to 300 mM.

3. In paragraph 1, A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that in the above fragrance mixture production step, the HP-β-CD (2-Hydroxypropyl-β-cyclodextrin) aqueous solution and the fragrance are added at a molar concentration ratio of 3:

2.

4. In paragraph 1, A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that the ultrasonic treatment in the above fragrance aqueous solution solubilization step is performed at 45 to 55°C for 55 to 65 minutes.

5. In paragraph 1, A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that in the first W1 / O (water-in-oil) emulsion production step, the mixing is performed using a probe sonicator for 1 to 3 minutes.

6. In paragraph 1, A method for producing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that in the above second W1 / O / W2 (water-in-oil-in-water) emulsion production step, the homogenization is performed using a homogenizer at 13,000 to 14,000 rpm for 3 to 8 minutes.

7. In paragraph 1, A method for manufacturing eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that the manufactured secondary W1 / O / W2 (Water-in-oil-in-water) emulsion is stirred at 400 to 600 rpm for 2 to 4 hours in the above fragrance capsule manufacturing step.

8. A eugenol fragrance capsule using polyhydroxyalkanoate, characterized in that it is manufactured by any one of the methods of claims 1 to 7.

9. In paragraph 8, Eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that the fragrance encapsulation rate of the above fragrance capsules is 9 to 11%.

10. In paragraph 8, Eugenol fragrance capsules using polyhydroxyalkanoate, characterized in that the average diameter of the fragrance capsules is 3.0 to 3.5 ㎛.

Images