Preparation method of hydrangea-shaped layered double hydroxide

Abstract

The invention relates to a method for preparing hydrangea-shaped layered double hydroxides, in particular to a method for preparing hydrangea-shaped layered double hydroxides with a wide specific surface area through a coprecipitation method. Wherein a NaOH solution and a mixed solution of a solution containing divalent metal cations and a solution containing trivalent metal cations are added into a solution containing anions, and the pH value is kept between 9 and 11.

Description

Technical Field

[0001] This invention relates to a method for preparing a layered bimetallic hydroxide in the shape of a hydrangea flower. More specifically, this invention relates to a method for preparing a layered bimetallic hydroxide in the shape of a hydrangea flower with a large specific surface area by co-precipitation, wherein a mixed solution containing divalent metal cations and a solution containing trivalent metal cations, along with a NaOH solution, are added to a solution containing anions, while maintaining the pH value between 9 and 11. Background Technology

[0002] Researchers are exploring various encapsulation technologies to provide greater stability for unstable cosmetic ingredients. Specifically, it is well known that light, heat, and oxygen in the air can severely reduce the bioactivity of functional ingredients.

[0003] Layered double hydroxides (LDHs) are attracting attention as one type of cosmetic active ingredient delivery system. LDHs are inorganic compounds with a layered structure, resembling the layers of geological formations. Generally, the composition of layered double hydroxides is based on formula M... 2+ 1-x M 3+ x (OH)2] x+ (A n- ) x / n ·mH2O represents this. In the formula, M 2+ and M 3+ It is a metallic cation located in the octahedral position of brucite, A n- This indicates anions located between layers. Typically, in a fixed composition phase, 0.2 ≤ x ≤ 0.33, n is 1 or 2, and m is 0.5 to 4.

[0004] LDH is fundamentally an inorganic material with structural properties that allow it to absorb a wide range of anions, from small gas molecules like carbon dioxide to biopolymers like DNA. Furthermore, molecules embedded in the layers maintain energy stability through electrostatic interactions with the inorganic layers. Anions exhibit the property of being absorbed or released via ion exchange. Since the inorganic layers are composed of various components ranging from alkali metals to transition metals, they can be used as precursors for catalysts, magnetic materials, electronic materials, and more. Recently, mechanisms for self-assembling LDH nanomaterials using specific molecular linkages or for controlling the release of anions from the layers in specific environments by selectively inducing surface reactions in the inorganic layers have been discovered, thus attracting attention as a sensor or drug delivery material. Specifically, if the electrostatic attraction between the layers is chemically minimized, nanolayers as thick as 1 nm can be isolated. This has become a fundamental powder that greatly enhances the applicability of LDH materials, which have already been applied in fields such as nanoelectronics, magento-optics, and nanosensors. Furthermore, LDH nanolayers exhibit excellent adsorption capacity for functional organic molecules. With the development of technologies such as enhancing the adsorption capacity of active ingredients in cosmetics and controlling release based on chemical environments, they are attracting attention as a novel bioencapsulation material. As an example of a method for preparing LDH, Korean Patent Application Publication No. 10-2019-0019150 discloses a method for preparing LDH that imparts high surface area and pore volume, including a specific solvent treatment step in the preparation process.

[0005] [Existing Technical Documents] [Patent Literature] Korean Patent Application Publication No. 10-2019-0019150 Summary of the Invention

[0006] (a) Technical problems to be solved Therefore, the technical problem of the present invention is to provide a method for preparing layered bimetallic hydroxides with the above-mentioned advantages in the form of a large specific surface area, so that various functional cosmetic ingredients can be effectively delivered to the skin in a more stable state.

[0007] In addition, another technical problem of the present invention is to provide a cosmetic composition comprising a layered bimetallic hydroxide prepared according to the above method and an active ingredient.

[0008] (II) Technical Solution To address the aforementioned technical problems, this invention provides a method for preparing layered bimetallic hydroxides with a large specific surface area via co-precipitation, wherein a mixed solution containing divalent metal cations and a solution containing trivalent metal cations, along with a NaOH solution, are added to a solution containing anions, while maintaining the pH value between 9 and 11.

[0009] In addition, the present invention provides a cosmetic composition comprising a layered bimetallic hydroxide prepared according to the above method and an active ingredient.

[0010] The present invention will be described in detail below.

[0011] According to one aspect of the present invention, a method for preparing a layered bimetallic hydroxide in the shape of a hydrangea flower is provided, the method comprising: i) Add a mixture of a solution containing divalent metal cations and a solution containing trivalent metal cations, along with NaOH solution, to a solution containing anions, while maintaining the pH value between 9 and 11; ii) The mixed solution obtained in step (i); iii) Filter the product obtained in step (ii) through a Buchner funnel and wash with distilled water until the pH reaches 6 to 8; iv) Add solvent to the product collected at the top of the Buchner funnel obtained in step (iii) and stir; and v) Filter the product obtained in step (iv) through a Buchner funnel and dry it.

[0012] The layered bimetallic hydroxide prepared according to the method of the present invention can provide a large specific surface area in the shape of a hydrangea (see...). Figure 4 and Figure 5 Therefore, it is referred to in this paper as "hydrangea-shaped layered double hydroxide".

[0013] In one embodiment of the present invention, the divalent metal cation in step (i) may be Ca. 2+ Mg 2+ Zn 2 + Ni 2+ Mn 2+ Co 2+ or Fe 2+ However, it is not limited to this.

[0014] In one embodiment of the present invention, the trivalent metal cation in step (i) may be Al 3+ Cr 3+ Mn 3 + Fe 3+ Ga 3+ Co 3+ or Ni 3+ However, it is not limited to this.

[0015] In one embodiment of the present invention, the anion in step (i) may be OH-. - F - Cl - ,Br - I - NO3 - CO3 2- or SO4 2- However, it is not limited to this.

[0016] According to one embodiment of the present invention, in step (i), NaOH can be used at a concentration of 2 to 5 M, 3 to 5 M, 3.5 to 4.5 M or 4 M.

[0017] According to one embodiment of the present invention, in step (i), the pH value of the solution containing anions can be maintained at 9.2 to 10.8, or 10 ± 0.5.

[0018] According to one embodiment of the present invention, in step (i), a mixed solution containing divalent metal cations and a solution containing trivalent metal cations, along with NaOH solution, can be added to the solution containing anions at a rate of 1 to 4 mL / min, 1.2 to 3 mL / min, or 1.5 to 2.5 mL / min.

[0019] According to one embodiment of the present invention, in step (ii), the mixed solution may be stirred for 30 minutes to 2 hours, 40 minutes to 1.5 hours or 1 hour.

[0020] According to one embodiment of the invention, in step (iii), the solution can be filtered using a Buchner funnel and then washed with distilled water until the pH reaches 6 to 8, or 7.

[0021] According to one embodiment of the invention, in step (iii), the solution may be washed with distilled water until the pH reaches 6 to 8, and then further washed with ethanol.

[0022] In one embodiment of the invention, the solvent in step (iv) may be ethanol.

[0023] According to one embodiment of the invention, in step (iv), stirring can be carried out for 12 to 36 hours, 16 to 32 hours, or 20 to 28 hours.

[0024] According to one embodiment of the invention, the drying in step (v) can be performed using a vacuum chamber at room temperature.

[0025] In one embodiment of the present invention, the BET surface area of ​​the hydrangea-shaped layered bimetallic hydroxide prepared by the above method can be 200 m². 2 / g or more, 210 m 2 / g or more, 220 m 2 / g or more, 230 m 2 / g or more, 240 m 2 / g or more, 250 m 2 / g or more, 260 m 2 / g or more, 270 m 2 / g or more or 280 m 2 / g or more. In one embodiment of the invention, the BET surface area of ​​the hydrangea-shaped layered bimetallic hydroxide prepared by the above method can be, for example, 250 to 300 m². 2 / g.

[0026] According to another aspect of the present invention, a cosmetic composition is provided comprising a hydrangea-shaped layered bimetallic hydroxide prepared by the method described above and an active ingredient.

[0027] In one embodiment of the invention, examples of active ingredients include, but are not limited to, one or more selected from the group consisting of: moisturizers, whitening agents, anti-wrinkle agents, UV blockers, hair growth promoters, vitamins or derivatives thereof, amino acids or peptides, anti-inflammatory agents, acne treatment agents, bactericides, estrogens, exfoliants, and natural products.

[0028] Examples of moisturizers include, but are not limited to, creatine, polyglutamic acid, sodium lactate, hydroxyproline, sodium 2-pyrrolidone-5-carboxylate, hyaluronic acid, sodium hyaluronate, ceramides, phytosterols, cholesterol, sitosterol, pullulan, and proteoglycans. Examples of skin-whitening agents include, but are not limited to, arbutin and its derivatives, kojic acid, bisabolol, niacinamide, vitamin C and its derivatives, placenta, allantoin, and asiaticoside. Examples of anti-wrinkle agents include, but are not limited to, retinol, retinol derivatives, retinaldehyde, adenosine, licorice extract, red ginseng extract, and ginseng extract. Examples of UV blockers include, but are not limited to, benzophenone derivatives, para-aminobenzoic acid derivatives, methoxycinnamic acid derivatives, salicylic acid derivatives, and avobenzone. There are no particular limitations on hair growth promoters, but blood circulation promoters and / or hair follicle stimulants are preferred. Examples of blood circulation promoters include, but are not limited to, *Swertia japonica* extract, *Swertia zedoaria* extract, vitamin E and its derivatives, and γ-oryzanol. Examples of hair follicle stimulants include, but are not limited to, capsicum tincture, ginger tincture, cantharides tincture, and benzyl nicotinate. Examples of vitamins or their derivatives include, but are not limited to, vitamin A (retinol) and its derivatives, vitamin B1, vitamin B2, vitamin B6, vitamin E and its derivatives, vitamin D, vitamin H, vitamin K, pantothenic acid and its derivatives, biotin, panthenol, and coenzyme Q. 10And idebenone. Examples of amino acids or peptides include, but are not limited to, cysteine, methionine, serine, lysine, tryptophan, amino acid extracts, epidermal growth factor (EGF), insulin-like growth factor (IGF), fibroblast growth factor (FGF), copper peptides, copper tripeptide-1, tripeptide-29, tripeptide-1, acetyl hexapeptide-8, nicotinyl tripeptide-35, hexapeptide-12, hexapeptide-9, palmitoyl pentapeptide-4, palmitoyl tetrapeptide-7, palmitoyl tripeptide-29, palmitoyl tripeptide-1, nonapeptide-7, tripeptide-10, citrulline, sh-polypeptide-15, palmitoyl tripeptide-5, diaminopropionoyl tripeptide-33, and r-spider polypeptide-1. Examples of anti-inflammatory agents include, but are not limited to, β-glycyrrhetinic acid, glycyrrhetinic acid derivatives, aminocaproic acid, hydrocortisone, β-glucan, and licorice. Examples of acne treatment agents include, but are not limited to, estradiol, estrogen, ethinyl estradiol, and azelaic acid. Examples of bactericides include, but are not limited to, benzalkonium chloride, benzyl chloride, and halocarban. There are no particular restrictions on estrogen, but estrogen is preferred. As an estrogen, it can preferably be estradiol, ethinyl estradiol, or isoflavones as phytoestrogens. Examples of keratolytic agents include, but are not limited to, sulfur, salicylic acid, AHA, BHA, and resorcinol. Examples of extracts of natural products or components obtained therefrom include, but are not limited to, extracts of the following: Japanese witch hazel, short-stalked wild sesame, white flower snake tongue grass, palm-leaved rhubarb, licorice, aloe vera, chamomile, rosehip, European horse chestnut, ginseng, Egyptian loofah, cucumber, nori, wakame, yam, snail, multi-stalked yam, and centella asiatica fruits, or juniper alcohol and β-carotene. In addition, yeast extract, collagen, elastin, DHA, EPA, flavor ingredients, etc., can be used.

[0029] If desired, the cosmetic compositions of the present invention may also contain ingredients such as stabilizers, antioxidants, and lubricants.

[0030] (III) Beneficial Effects The hydrangea-shaped layered bimetallic hydroxide prepared according to the present invention can very effectively deliver cosmetic active ingredients to the skin in a stable form by providing a large specific surface area. Attached Figure Description

[0031] Figure 1 This is a schematic diagram illustrating the preparation method of Example 1.

[0032] Figure 2 These are photographs showing a volume comparison between the hydrangea-shaped layered bimetallic hydroxide (HLDH) of the present invention and the conventional layered bimetallic hydroxide (PLDH).

[0033] Figure 3 The FT-IR analysis results of the hydrangea-shaped layered bimetallic hydroxide (HLDH) and the conventional layered bimetallic hydroxide (PLDH) of the present invention are shown.

[0034] Figure 4 These are scanning electron microscope images of the hydrangea-shaped layered bimetallic hydroxide (HLDH) and the conventional layered bimetallic hydroxide (PLDH) of the present invention.

[0035] Figure 5 These are scanning electron microscope images of the HLDH containing avobenzone from Example 2 and the PLDH containing avobenzone from Comparative Example 1.

[0036] Figure 6 The FT-IR analysis results of HLDH containing avobenzone in Example 2 and PLDH containing avobenzone in Comparative Example 1 are shown.

[0037] Figure 7 The HPLC analysis results of HLDH containing avobenzone in Example 2 and PLDH containing avobenzone in Comparative Example 1 are shown.

[0038] Figure 8 The particle distribution and zeta potential measurement results in Experiment Example 3 are shown.

[0039] Figure 9 A graph showing the measurement results of the improvement in skin hydration in Experiment Example 5.

[0040] Figure 10 The graph shows the improvement rate of skin hydration measured in Experimental Example 5.

[0041] Figure 11 A graph showing the measurement results of the degree of improvement in the desquamation index in Experimental Example 6.

[0042] Figure 12 The graph shows the improvement rate of the desquamation index measured in Experimental Example 6. Detailed Implementation

[0043] The invention will be explained in more detail below through the following embodiments. However, it must be understood that the scope of protection of the invention is not limited to these embodiments.

[0044] Example 1: Preparation of hydrangea-shaped layered bimetallic hydroxides A layered bimetallic hydroxide containing carbonate ions was synthesized by the following coprecipitation method. A mixed solution (A) containing 1.875 M Mg(NO3)2·6H2O (Duksan Science, South Korea) and 0.625 M Al(NO3)3·9H2O (Duksan Science, South Korea) dissolved in distilled water, and a solution (B) containing 4 M NaOH (Duksan Science, South Korea) were slowly added to a 0.5 M Na2CO3 (Duksan Science, South Korea) solution (C) using a pump. During the addition, the pH of the mixed solution (C) was maintained at 10.0 ± 0.5. The mixed solution was stirred for approximately 1 hour, filtered through a Buchner funnel, washed with distilled water until the pH reached 7, and then washed with ethanol. The clay-like substance collected at the top of the Buchner funnel was returned to the ethanol and stirred for one day. The product was filtered through a Buchner funnel and then vacuum dried at room temperature using a vacuum chamber to obtain a hydrangea-shaped layered double hydroxide (hereinafter referred to as "HLDH"). The chemical formula of the synthesized HLDH is as follows: [Mg3Al(OH)8]CO3·xH2O.

[0045] To compare with the above-mentioned HLDH, the conventional layered bimetallic hydroxide Mg4Al2(OH) 12 CO3·3H2O (plate-shaped layered double hydroxide, hereinafter referred to as "PLDH") was purchased from Dansuk Co., Ltd. (South Korea).

[0046] Example 2: Preparation of HLDH containing avobenzone 6 g PARSOL ® 1789 (avobenzone) was dispersed in a 1:1 aqueous solution of water and ethanol. 50 mL of distilled water containing 1.5 g of sodium hydroxide was added to the result, and the mixture was stirred at room temperature for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at 80°C for 5 hours. The mixture was then washed with hot distilled water and ethanol using a Buchner funnel and filtered. The clay-like substance collected at the top of the Buchner funnel was vacuum-dried at room temperature using a vacuum chamber.

[0047] Comparative Example 1: Preparation of PLDH containing avobenzone Except that PLDH was used instead of HLDH, PLDH containing avobenzone was prepared in the same manner as in Example 2.

[0048] Example 3: Preparation of HLDH containing collagen Disperse 10g of collagen in water and stir for 30 minutes. Add 10g of HLDH to the mixture, stir at room temperature for 24 hours, then wash with distilled water and ethanol using a centrifuge and filter. Vacuum dry the clay-like substance collected at the bottom using a vacuum chamber at room temperature.

[0049] Example 4: Preparation of HLDH containing hyaluronic acid Disperse 0.5 g of hyaluronic acid in water and stir for 30 minutes. Add 10 g of HLDH to the mixture, stir at room temperature for 24 hours, then wash with distilled water and ethanol using a centrifuge and filter. Vacuum dry the clay-like material collected at the bottom using a vacuum chamber at room temperature.

[0050] Example 5: Preparation of HLDH containing ceramide 1.5 g of ceramide was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0051] Example 6: Preparation of HLDH containing retinol 4.5 g of retinol was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0052] Example 7: Preparation of HLDH containing retinaldehyde 5 g of retinaldehyde was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0053] Example 8: Preparation of HLDH containing arbutin 5 g of arbutin was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0054] Example 9: Preparation of HLDH containing tocopherol 5 g of tocopherol was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0055] Example 10: Preparation of HLDH containing EGF 5 g of epidermal growth factor (EGF) was dispersed in water and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0056] Example 11: Preparation of HLDH containing copper peptide Disperse 5 g of copper peptide in water and stir for 30 minutes. Add 10 g of HLDH to the mixture, stir at room temperature for 24 hours, then wash with distilled water and ethanol using a centrifuge and filter. Vacuum dry the clay-like material collected at the bottom using a vacuum chamber at room temperature.

[0057] Example 12: Preparation of HLDH containing β-glucan Disperse 5 g of β-glucan in water and stir for 30 minutes. Add 10 g of HLDH to the mixture, stir at room temperature for 24 hours, then wash with distilled water and ethanol using a centrifuge and filter. Vacuum dry the clay-like material collected at the bottom using a vacuum chamber at room temperature.

[0058] Example 13: Preparation of HLDH containing isoflavones 5 g of isoflavones were dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0059] Example 14: Preparation of HLDH containing salicylic acid 5 g of salicylic acid was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0060] Example 15: Preparation of HLDH containing Centella Asiatica extract Disperse 5 g of Centella asiatica extract in water and stir for 30 minutes. Add 10 g of HLDH to the mixture, stir at room temperature for 24 hours, then wash with distilled water and ethanol using a centrifuge and filter. Vacuum dry the clay-like material collected at the bottom using a vacuum chamber at room temperature.

[0061] Example 16: Preparation of HLDH containing asiaticoside 5 g of asiaticoside was dispersed in a 1:1 aqueous solution of water and ethanol and stirred for 30 minutes. 10 g of HLDH was added to the mixture, and the mixture was stirred at room temperature for 24 hours. The mixture was then washed with distilled water and ethanol using a centrifuge and filtered. The clay-like material collected at the bottom was vacuum-dried at room temperature using a vacuum chamber.

[0062] Example 17 and Comparative Example 2: Preparation of a face cream containing avobenzone The components of phases A, B-1, B-2, and C in Table 1 were mixed separately. Phases A and B-2 were mixed at a temperature above 75°C. After the components were completely dissolved, they were mixed for a period of time using a homogenizer, and then cooled to prepare the face cream.

[0063] [Table 1]

[0064] (Unit: g) Example 18 and Comparative Example 3: Preparation of a face cream containing hyaluronic acid The components of phases A, B-1, B-2, and C in Table 2 were mixed separately. Phases A and B-2 were mixed at a temperature above 75°C. After the components were completely dissolved, they were mixed for a period of time using a homogenizer, and then cooled to prepare the face cream.

[0065] [Table 2]

[0066] (Unit: g) Example 19 and Comparative Example 4: Preparation of face cream containing retinol The components of phases A, B-1, B-2, and C in Table 3 were mixed separately. Phases A and B-2 were mixed at a temperature above 75°C. After the components were completely dissolved, they were mixed for a period of time using a homogenizer, and then cooled to prepare the face cream.

[0067] [Table 3]

[0068] (Unit: g) Experimental Example 1: LDH Analysis When the PLDH and HLDH of this invention were measured by the BET method, the specific surface area of ​​the PLDH was 150 m². 2 / g, while the specific surface area of ​​HLDH is 285.58 m². 2 / g. This result confirms that HLDH, with its hydrangea-like shape, has a larger specific surface area. Furthermore, as a volume comparison experiment, placing the same amount of 2g into the same vial confirmed that HLDH has a volume four times larger ( Figure 2 ).

[0069] The chemical functional groups were identified by Fourier transform infrared spectroscopy (FT-IR), confirming the structure of the synthesized HLDH. Figure 3 (At 3,250-3,500 cm) -1 The broad absorption band observed in the region is attributed to the hydroxyl group (OH) in PLDH, and at 1,655 cm⁻¹ -1 The strong absorption band at that point is attributed to the carbonate anion (CO3). 2- ). 900 cm -1 The absorption bands that appear below are attributed to the combination of aluminum and oxygen, as well as magnesium and oxygen.

[0070] Furthermore, the shape and size of the PLDH and HLDH of the present invention were examined using a scanning electron microscope (SEM). Figure 4 PLDH exhibits a plate-like structure, while HLDH displays a hydrangea-like shape. This supports the results of the BET analysis, which indicates that HLDH has a wider specific surface area.

[0071] Experimental Example 2: LDH Analysis of Avobenzone FT-IR analysis was performed to analyze the structures of the avobenzone-containing HLDH of Example 2 and the avobenzone-containing PLDH of Comparative Example 1. The spectra were measured at 3,250–3,500 cm⁻¹, respectively. -1 1,655 cm -1 and 900 cm -1 Absorption bands were observed at [location name]. Additionally, PARSOL was observed. ® Absorption band of 1789 (avobenzone): 2,970 cm⁻¹ -1 Carbon-hydrogen bonds (CH) at 1,600 cm -1 The carbon-oxygen double bond (C=O) at 1,050-1,250 cm⁻¹ -1 The carbon-oxygen single bond (CO) at that location.

[0072] Furthermore, SEM analysis confirmed the shape and size of the HLDH of Example 2 and the PLDH of Comparative Example 1. Figure 5 Specifically, in the case of HLDH in Example 2, PARSOL was found to be... ®1789 was uniformly trapped between hydrangea-shaped particles with a large specific surface area. Furthermore, to confirm the active ingredient PARSOL... ® Whether 1789 was trapped in layered bimetallic hydroxides was analyzed using ethanol solvent and a UV-Vis spectrophotometer. Figure 6 ). Although the existing PARSOL ® 1789 showed a maximum peak at 358 nm, but both the HLDH of Example 2 and the PLDH of Comparative Example 1 were confirmed to have a maximum peak at 358 nm. The HLDH of Example 2 had a higher starting value, indicating that PARSOL... ® The content of 1789 was relatively high. High-performance liquid chromatography (HPLC) analysis was performed to quantitatively analyze the PARSOL in the HLDH of Example 2 and the PLDH of Comparative Example 1. ® 1789 content ( Figure 7 In the case of PLDH in Comparative Example 1, the content was 12.56%, while in the case of HLDH in Example 2, which used hydrangea-shaped HLDH with a large specific surface area, the content was found to be about twice as high at 26.71%.

[0073] Experimental Example 3: Measurement of Particle Distribution and Zeta Potential The particle distribution and zeta potential of the hyaluronic acid-containing PLDH and HLDH in Example 4 were measured using a Photal ELS-Z (Photal, Japan). The average particle sizes of the PLDH and HLDH in Example 4 were 694.4 nm and 1979.2 nm, respectively. The zeta potentials of the PLDH and HLDH in Example 4 were +17.01 nm and -11.47 nm, respectively. Figure 8 ).

[0074] Experiment Example 4: Measurement of UV Protection Effect The UV protection efficacy was measured using face creams containing avobenzone from Example 17 and Comparative Example 2. The results showed that the face cream containing the HLDH of the present invention in Example 17 had a higher PA index (UVA protection level) and less avobenzone compared to the face cream of Comparative Example 2, which had avobenzone added as is.

[0075] Experiment Example 5: Measurement of Moisturizing Effect After applying the hyaluronic acid-containing face creams of Example 18 and Comparative Example 3, the results were measured using a Corneometer. ® The probe on the CM825 (Courage + Khazaka electronic GmbH, Germany) was placed vertically on the skin surface and gently pressed to measure moisture content. The face cream of Example 18, containing the HLDH of this invention, was confirmed to have better moisturizing effects than the face cream of Comparative Example 3, which directly added hyaluronic acid. Figure 9 and Figure 10 ).

[0076] Experiment Example 6: Measurement of the effect of improving the stratum corneum After applying the hyaluronic acid-containing creams of Example 18 and Comparative Example 3, stratum corneum samples were collected from the skin surface using a Corneofix F20 (Courage + Khazaka electronic GmbH, Germany). The skin surface was analyzed using a Visioscan VC98 (Courage + Khazaka electronic GmbH, Germany) to measure the improvement in stratum corneum. The cream of Example 18, containing the HLDH of the present invention, was confirmed to show a better exfoliation index (EI) than the cream of Comparative Example 3, which directly added hyaluronic acid. Figure 11 and 12 ).

[0077] Experiment Example 7: Test on the effect of promoting transdermal absorption The artificial skin Neoderm (Tego Science, Korea) was implanted into a Franz-type diffusion cell (Lab Fine Instruments, Korea). 50 mM phosphate-buffered saline (pH 7.4, 0.1 M NaCl) was added to the recipient cells (5 ml) in the Franz-type diffusion cell. The diffusion cell was then mixed and diffused at 600 rpm and 32°C, and 50 μl of retinol-containing creams from Example 19 and Comparative Example 4 were added to the donor cells. Absorption and diffusion were carried out according to the predetermined time, with a skin area of ​​0.64 cm² undergoing absorption and diffusion. 2 After the absorption and diffusion of the active ingredient were completed, any unabsorbed residue remaining on the skin was washed off with dry Kimwipes™ or 10 mL of ethanol. The skin was then homogenized using a probe homogenizer to absorb and diffuse the active ingredient, followed by extraction of retinol absorbed into the skin with 4 mL of dichloromethane. The extract was then filtered through a 0.45 μm nylon membrane filter. The retinol content was measured by high-performance liquid chromatography (HPLC) under the following conditions, and the results are shown in Table 4.

[0078] [Table 4]

Claims

1. A method for preparing a layered bimetallic hydroxide in the shape of a hydrangea flower, the method comprising: i) Add a mixture of a solution containing divalent metal cations and a solution containing trivalent metal cations, along with NaOH solution, to a solution containing anions, while maintaining the pH value between 9 and 11; ii) The mixed solution obtained in step (i); iii) Filter the product obtained in step (ii) through a Buchner funnel and wash it with distilled water until the pH reaches 6 to 8; iv) Add solvent to the product collected at the top of the Buchner funnel obtained in step (iii) and stir; and v) Filter the product obtained in step (iv) through a Buchner funnel and dry it.

2. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein the divalent metal cation in step (i) is Ca. 2+ Mg 2+ Zn 2+ Ni 2+ Mn 2+ Co 2+ or Fe 2+ .

3. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein the trivalent metal cation in step (i) is Al. 3+ Cr 3+ Mn 3+ Fe 3+ Ga 3+ Co 3+ or Ni 3+ .

4. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein the anion in step (i) is OH-. - F - Cl - ,Br - I - NO3 - CO3 2- or SO4 2- .

5. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein 2-5M NaOH is used in step (i).

6. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein in step (i), the pH of the solution containing the anion is maintained between 9.2 and 10.

8.

7. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 6, wherein in step (i), the pH of the solution containing the anion is maintained at 10 ± 0.

5.

8. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein in step (i), a mixed solution containing divalent metal cations and a solution containing trivalent metal cations, as well as a NaOH solution, are added to the solution containing anions at a rate of 1 mL / min to 4 mL / min.

9. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein in step (ii), the mixed solution is stirred for 30 minutes to 2 hours.

10. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein step (iii) further comprises washing with ethanol.

11. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein the solvent in step (iv) is ethanol.

12. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein stirring is carried out for 12 to 36 hours in step (iv).

13. The method for preparing a layered bimetallic hydroxide in the shape of a hydrangea according to claim 1, wherein the drying in step (v) is carried out in a vacuum chamber at room temperature.

14. The method for preparing a hydrangea-shaped layered bimetallic hydroxide according to claim 1, wherein the BET surface area of ​​the hydrangea-shaped layered bimetallic hydroxide is 200 m². 2 / g or more.

15. A cosmetic composition comprising a hydrangea-shaped layered bimetallic hydroxide prepared by the method of any one of claims 1 to 14 and an active ingredient.

16. The cosmetic composition according to claim 15, wherein the active ingredient is selected from the group consisting of: moisturizers, whitening agents, anti-wrinkle agents, UV blockers, hair growth promoters, vitamins or derivatives thereof, amino acids or peptides, anti-inflammatory agents, acne treatment agents, bactericides, estrogens, exfoliating agents, and natural products.

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