Liquid Crystal Emulsion Cosmetic Composition for Improving Sebum-Moisture Balance of Acne-Prone Skin, and Method for Preparing the Same

Abstract

The present invention relates to a cosmetic composition for acne-prone skin and a method for manufacturing the same, which minimizes the use of purified water and uses tea tree leaf water (40 to 55 wt%) as a single high-concentration base, encapsulates neem oil and black cumin seed oil in a multilayer lamellar structure using a cetearyl oliveate / sorbitan oliveate-based liquid crystal emulsifier to ensure off-odor masking and formulation stability, and combines jojoba oil having a sebum-like structure with low molecular weight hyaluronic acid to improve the oil-water balance. The manufacturing method is characterized by a three-step temperature control process of 75 to 80°C (emulsification) → 50 to 55°C (addition of plant extract) → 45°C or lower (addition of essential oil), thereby exhibiting excellent formulation stability along with inhibition of acne-causing bacteria, improvement of oil-water balance, and strengthening of the skin barrier.

Description

Technology Field

[0001] The present invention relates to a cosmetic composition for acne-prone skin care and a method for manufacturing the same. More specifically, the invention relates to a cosmetic composition for acne-prone skin and a method for manufacturing the same, which minimizes the content of purified water and uses high-concentration tea tree leaf water, which has excellent antibacterial efficacy, as a single aqueous base; improves the oil-water balance of acne-prone skin by replenishing insufficient oil with oily components such as jojoba oil having a sebum-like structure, while simultaneously supplying immediate moisture with low molecular weight hyaluronic acid, and maximizes skin absorption rate and formulation stability by stabilizing poorly soluble natural antibacterial oil using a liquid crystal emulsion system. Background Technology

[0003] Generally, acne-prone skin is caused by the complex interplay of hormonal imbalances, stress, excessive sebum secretion, clogged pores due to keratin thickening, and the proliferation of acne bacteria (Propionibacterium acnes, P.acnes). To address this, conventional acne care products have often used purified water as a base and high concentrations of salicylic acid (BHA), alcohol, and synthetic antibiotics to provide strong sterilization and sebum control.

[0005] However, while these chemical prescriptions provide a temporary sebum-suppressing effect, they have the problem of causing extreme dryness and damaging the skin barrier in the long run, thereby making the skin more sensitive and worsening chronic skin troubles.

[0006] In particular, if the focus is placed on suppressing sebum to the point where the supply of oil becomes insufficient, the skin is prone to falling into a vicious cycle of overproducing sebum to compensate for the lack of oil; consequently, there was a problem in that the oil-moisture balance was more likely to collapse in acne-prone skin.

[0007] In addition, most cosmetics use purified water in amounts of more than 50%, or even more than 70%, of the total weight to reduce costs, making it difficult to expect physiological activity effects from the solvent itself.

[0009] Meanwhile, although natural antimicrobial ingredients such as neem oil or black cumin oil have excellent efficacy, there were technical limitations in that they were difficult to stabilize at high concentrations because they had a very strong peculiar odor and were prone to oxidation or separation within the formulation.

[0010] In addition, natural extracts or essential oils that are sensitive to heat frequently lost their efficacy when exposed to high temperatures during the manufacturing process.

[0012] Accordingly, the applicant has conducted extensive research to overcome the problems of the prior art described above and has discovered that by minimizing purified water and formulating tea tree leaf water as a single high-concentration aqueous base, while also combining jojoba oil having a sebum-like structure with low molecular weight hyaluronic acid to improve the oil-water balance, and by introducing a liquid crystal emulsion system to encapsulate poorly soluble antimicrobial oils such as neem oil and black cumin oil in a lamellar structure, it is possible to achieve formulation stability and off-odor masking while exhibiting antimicrobial efficacy from the base stage, thereby completing the present invention. The problem to be solved

[0014] The technical problem that the present invention aims to solve is as follows.

[0016] First, it minimizes the use of purified water and utilizes a high concentration of tea tree leaf water as a sole aqueous base to provide a powerful antibacterial effect starting from the base stage, while simultaneously improving the oil-water balance of acne-prone skin by combining light oily ingredients, such as jojoba oil with a sebum-like structure, with moisturizing ingredients, such as low molecular weight hyaluronic acid.

[0017] Second, by introducing a liquid crystal emulsification system, plant oils such as neem oil and black cumin oil, which have strong antibacterial and anti-inflammatory effects but are difficult to stabilize, are captured in a lamellar structure, thereby masking the peculiar odor and ensuring formulation stability.

[0018] Third, it provides an optimized manufacturing process that lowers the temperature in stages to prevent the deterioration of efficacy of heat-sensitive natural essential oils and extracts. means of solving the problem

[0020] A liquid crystal emulsion type cosmetic composition for improving the oil-water balance of acne-prone skin according to one aspect of the present invention for solving the above problem is,

[0021] It is characterized by comprising, based on the total weight, an aqueous base containing tea tree leaf water which is included as a base replacing purified water and provides antibacterial and astringent effects; an antibacterial oil component containing neem oil and black cumin oil as antibacterial active ingredients; an oil-balancing component containing jojoba oil which has a sebum-like structure to replenish insufficient oil; a moisturizing component containing low molecular weight hyaluronic acid which provides immediate moisture; and a liquid crystal emulsifier that encapsulates the antibacterial oil component and the oil-balancing component in a multilayer lamellar structure to mask off-odors and prevent oxidation.

[0023] According to a preferred embodiment of the present invention, the liquid crystal emulsifier is an olive oil-derived emulsifier comprising cetearyl oliveate and sorbitan oliveate.

[0025] According to a preferred embodiment of the present invention, the composition may comprise, based on the total weight, 40 to 55 weight% of tea tree leaf water, 4.0 to 8.0 weight% of liquid crystal emulsifier, 0.1 to 1.0 weight% of neem oil, 0.5 to 3.0 weight% of black cumin oil, 1.5 to 3.0 weight% of jojoba oil, and 0.05 to 0.2 weight% of low molecular weight hyaluronic acid. More preferably, the composition may comprise 45 to 52 weight% of tea tree leaf water, 4.5 to 6.5 weight% of liquid crystal emulsifier, 0.3 to 0.7 weight% of neem oil, 1.0 to 2.0 weight% of black cumin oil, 1.8 to 2.5 weight% of jojoba oil, and 0.08 to 0.15 weight% of low molecular weight hyaluronic acid.

[0027] A manufacturing method according to another aspect of the present invention is,

[0028] (a) a step of dissolving an aqueous material containing tea tree leaf water, a natural chelating agent, and glycerin by heating it to 75 to 80°C; (b) a step of completing an aqueous base by slowly adding and dispersing a thickening agent containing a natural gum complex and low molecular weight hyaluronic acid, then adding it to the aqueous material of step (a) and stirring uniformly; (c) a step of dissolving an oil phase material containing a liquid crystal emulsifier, neem oil, black cumin seed oil, green tea oil, and moisturizing oil components by heating it to 75 to 80°C; (d) an emulsification step of operating a mixer containing the aqueous base of step (b) at 3,000 to 4,000 rpm, slowly adding the oil phase material of step (c), and stirring for 10 to 15 minutes to form a liquid crystal with a multilayer lamellar structure; (e) a step of first cooling the result of step (d) to 50 to 55°C and then adding a plant extract complex; (f) a step of adjusting the pH of the final composition to 5.0 to 6.0 by adding a pH adjuster; and (g) a step of cooling the result of step (f) to 45°C or lower, then adding a directional additive and performing final mixing and degassing; characterized by including these steps. Effects of the invention

[0030] According to the present invention, the following effects can be expected.

[0032] First, antibacterial effect of a high-concentration single-aqueous base: By minimizing the use of purified water, a simple solvent, and incorporating a high concentration of tea tree leaf water (40 to 55 weight%) as a single-aqueous base, a strong antibacterial effect is exerted from the base stage, supporting the efficacy of the active ingredient. Terpinen-4-ol, the main component of tea tree leaf water, inhibits the proliferation of acne-causing bacteria (P. acnes).

[0034] Second, stabilization of poorly soluble antimicrobial oils and masking of off-odors: By applying a liquid crystal emulsion system, ingredients such as neem oil and black cumin oil, which have excellent efficacy but are difficult to stabilize and have peculiar odors, are stably captured within a lamellar structure. This prevents the rancidity of the oil and effectively masks off-odors, while improving the transdermal absorption rate of active ingredients through a skin-friendly lamellar structure.

[0036] Third, improvement of oil-moisture balance and strengthening of the skin barrier: Jojoba oil, which has a sebum-like structure, replenishes insufficient oil to alleviate signals of oil deficiency that trigger excessive sebum secretion, while low molecular weight hyaluronic acid balances oil and moisture by providing immediate hydration. Furthermore, a lamellar structure similar to the skin's lipid bilayer blocks external stimuli and inhibits moisture evaporation, repairing barrier damage—a chronic issue in acne-prone skin—and providing a non-sticky, highly moisturizing effect.

[0038] Fourth, effectiveness of the heat denaturation minimization process: Through a stepwise temperature control process leading from 75 to 80°C (emulsification) → 50 to 55°C (vegetable extract) → 45°C or lower (essential oil), the destruction of heat-sensitive physiologically active substances and natural fragrance components is minimized, thereby fully realizing the inherent efficacy of the raw materials in the finished product. Brief explanation of the drawing

[0040] Figure 1 is a photograph comparing the skin condition before (left) and after (right) using the cosmetic composition according to the present invention for 4 weeks. Specific details for implementing the invention

[0041] Preferred embodiments of the present invention will be described in detail below. However, the following embodiments are merely illustrative of the present invention, and the scope of the present invention is not limited to the following embodiments.

[0043] The present invention is based on the core principle of the organic combination of three technical elements: ① minimizing the use of purified water and introducing a high-concentration functional aqueous base consisting solely of tea tree leaf water; ② achieving oil-water balance by encapsulating oil-balancing ingredients, such as poorly soluble antibacterial oil and jojoba oil, in a multilayer lamellar structure using an olive oil-derived liquid crystal emulsifier; and ③ adding heat-sensitive ingredients through a stepwise temperature reduction process. Each ingredient is not merely listed but works organically with one another to improve the oil-water balance of acne-prone skin.

[0045] The specific formulation ratios of the cosmetic composition for acne-prone skin according to the present invention and the roles of each component are as shown in [Table 1] below.

[0047] [Example 1] Cosmetic composition and content for improving oil-moisture balance of acne-prone skin division Ingredient name Content (weight%) Functions and roles Prize A Tea tree leaf water 48.63 Antibacterial, anti-inflammatory, sebum-controlling base Prize A glycerin 10.00 Humectant (for water-soluble) Prize A plant-based preservative complex 3 natural preservative system Prize A natural chelating agents 0.02 Metal ion blockade, anti-discoloration Prize B Natural gum complex 0.3 Thickeners, formulation stabilization Prize B low molecular weight hyaluronic acid 0.1 Deep hydration, enhanced moisture retention C MCT oil 8 Lightweight oil base C Shea butter 7.5 High moisturizing, skin softening C liquid crystal emulsifier 5.5 Emulsifier, lamellar structure formation C Olive oil complex 3.3 Emulsification aid, increased skin compatibility C Black cumin oil 1.4 Specialized in anti-inflammatory and skin care C Green tea oil 1.05 Skin soothing, astringent, antioxidant C Watermelon seed oil 2.10 Pore ​​tightening, light moisturizing C Jojoba oil 2.10 Sebum-like structure, sebum control C Neem oil 0.35 Powerful antibacterial and antifungal action C Tocopherol 1.0 Antioxidant, prevents oil rancidity D-point Angelica and Ginseng Complex Extract 2 Skin vitality, improved blood circulation, soothing D-point Polygonum aviculare and reed complex extract 2 Soothes irritation, calms redness Prize E purified water 1 citric acid dissolving solvent Prize E Citric acid 0.1 pH control F-phase Naturally derived antibacterial agents 0.25 Enhanced preservation, antibacterial aid F-phase Lavender oil 0.1 Soothing aroma, sebum control F-phase Thyme leaf oil 0.1 Strong antibacterial action F-phase Tea tree leaf oil 0.1 Localized trouble care total 100

[0049] The composition according to [Example 2], which has enhanced antibacterial base and antibacterial oil components compared to [Example 1], is the same as [Table 1] in terms of the composition, except that the tea tree leaf water was changed from 48.63 wt% to 49.00 wt% and the neem oil from 0.35 wt% to 0.50 wt%, respectively, and the shea butter was reduced from 7.50 wt% to 6.98 wt% to offset the net increase / decrease (+0.52 wt%) of these changed components, and the remaining components and content are the same as [Table 1].

[0051] When the content of each component of [Example 2] adjusted as above is summed up, it matches exactly 100% by weight, just like [Table 1].

[0053] The ingredients adopted in this invention are not merely a list but work organically to improve the oil-moisture balance of acne-prone skin, and the specific functions and principles of the key ingredients are as follows.

[0055] The above Tea Tree Leaf Water has the scientific name Melaleuca Alternifolia Leaf Water. It is distilled water obtained by steam distillation of tea tree leaves, and its main component, terpinen-4-ol, exerts powerful antibacterial and antifungal effects, destroying the cell membranes of P. acnes, the causative bacteria of acne, and inhibiting their proliferation.

[0056] In the present invention, the content of tea tree leaf water is preferably 40 to 55 weight% based on the total weight, more preferably 45 to 52 weight%, and most preferably about 48.6 weight%. If the content is less than 40 weight%, the antibacterial activity is negligible, making it difficult to expect clinical improvement effects, and if it exceeds 55 weight%, there is a risk of skin irritation due to an excessive concentration of terpinene-4-ol.

[0058] The above green tea oil is a green tea with the scientific name Camellia Sinensis, and this green tea oil is an oil phase component that stably supports the extract of the green tea leaves (Camellia Sinensis Leaf Extract) and tocopherol using sunflower seed oil as a carrier (INCI name: Helianthus Annuus (Sunflower) Seed Oil, Camellia Sinensis Leaf Extract, Tocopherol).

[0059] The catechin and polyphenols of the above green tea leaf extract eliminate free radicals to alleviate oxidative stress and contribute to tightening enlarged pores through astringent action, while the sunflower seed oil carrier and contained tocopherol inhibit the oxidation of these active ingredients within the oil phase, thereby stabilizing them.

[0060] The content of the green tea oil is preferably 0.5 to 2.0 weight% based on the total weight, more preferably 0.8 to 1.3 weight%, and most preferably about 1.05 weight%. Below 0.5 weight%, the antioxidant and astringent effects are negligible, and above 2.0 weight%, there is a risk that the balance of the mixture with other oil components will be compromised.

[0062] The above-mentioned black cumin seed oil has the scientific name Nigella Sativa Seed Oil. Thymoquinone, the main component, suppresses the secretion of inflammatory cytokines (IL-1β, TNF-α) that cause pustular acne, thereby soothing pustular acne. The content is preferably 0.5 to 3.0 weight% based on the total weight, and more preferably 1.0 to 2.0 weight%. If the content is less than 1 weight%, the anti-inflammatory effect of thymoquinone is insufficient, and if it exceeds 2 weight%, there is a risk that pores may become clogged due to the oiliness.

[0064] The above-mentioned neem oil has the scientific name Melia Azadirachta Seed Oil. It contains azadirachtin and nimbin components, exhibiting strong antibacterial and antifungal activity. The content is preferably 0.1 to 1.0 weight% based on the total weight, and more preferably 0.3 to 0.7 weight%. Below 0.3 weight%, the antibacterial efficacy is insufficient, and above 0.7 weight%, a characteristic strong off-odor occurs, making it difficult to completely mask even with a liquid crystal emulsion structure. The liquid crystal emulsion system of the present invention is a core technology that effectively masks the off-odor of neem oil while maximizing the skin penetration of active ingredients.

[0066] The liquid crystal emulsifier described above is an olive oil-derived emulsifier with cetearyl olivate and sorbitan olivate as its main components. These components spontaneously form a multilayer lamellar phase at the interface between water and oil, and when observed at 400x magnification with a polarized light microscope, a Maltese Cross pattern, which is the inherent optical anisotropy of the liquid crystal, is clearly observed. This lamellar structure simultaneously performs three roles: ① stably trapping insoluble oil components (neem oil, black cumin oil, etc.) to prevent oxidation, ② masking strong off-flavors, and ③ forming a structure similar to the skin's lipid bilayer to improve transdermal absorption.

[0067] Furthermore, the above lamellar structure encapsulates and stabilizes oil-balancing ingredients such as jojoba oil and oil-phase active ingredients including green tea oil within the layered structure, thereby ensuring that oil-based ingredients involved in oil-water balance are uniformly dispersed and delivered to the skin. The content is preferably 4.0 to 8.0 weight% based on the total weight, and more preferably 4.5 to 6.5 weight%. Below 4.0 weight%, the lamellar structure is not sufficiently formed, resulting in formulation separation, and above 8.0 weight%, the formulation becomes excessively heavy, leading to a decrease in usability.

[0069] The above olive oil complex is a complex of oil components derived from olive oil, as a component distinct from the liquid crystal emulsifier (5). For example, it may include one or more selected from cetyl olivate, olive glycerides, and olive oil unsaponifiables. It assists in emulsification to promote the formation of a lamellar structure and improves the user experience by increasing skin affinity. The content is preferably 1.0 to 5.0 weight% based on the total weight, and more preferably 2.5 to 4.0 weight%.

[0071] The above-mentioned plant preservative complex is a naturally derived preservative system composed of one or more components selected from glyceryl caprylate, ethylhexylglycerin, and 1,2-hexanediol. It inhibits microbial growth without using synthetic preservatives (parabens, phenoxyethanol) and maintains low skin irritation.

[0073] The above natural chelating agent is a naturally derived metal ion chelating agent such as sodium gluconate or phytic acid. By using a naturally derived chelating agent in a range of 0.01 to 0.05 weight% instead of EDTA (ethylenediaminetetraacetic acid), trace amounts of metal ions that may be incorporated into the raw material are chelated, and discoloration and odor change of the composition are prevented.

[0075] delete

[0076] delete

[0077] The above natural gum complex is a thickening agent complex comprising one or more naturally derived polymers selected from xanthan gum and hydroxyethylcellulose (HEC). It is uniformly dispersed and added to ensure the viscosity and formulation stability of the composition. The content is preferably 0.1 to 0.6 weight% based on the total weight, and more preferably 0.2 to 0.4 weight%.

[0079] The above jojoba oil has the scientific name Simmondsia Chinensis Seed Oil. It has a wax ester structure similar to human sebum, and when absorbed into the skin, it alleviates signals of excessive sebum secretion from the sebaceous glands. At the same time, it contributes significantly to improving the oil-water balance of the present invention by replenishing insufficient oil without clogging pores due to its light texture. The content is preferably 1.5 to 3.0 weight% based on the total weight, more preferably 1.8 to 2.5 weight%, and most preferably about 2.1 weight%. Below 1.5 weight%, the oil replenishment effect is negligible, and above 3.0 weight%, there is a risk that the texture will become heavy.

[0081] The above low molecular weight hyaluronic acid is a hyaluronic acid that has been reduced in molecular weight to penetrate deep into the stratum corneum, and provides an immediate internal moisturizing effect, thereby completing the oil-water balance by acting complementarily with the oil-replenishing effect of the above jojoba oil. The content is preferably 0.05 to 0.2 weight% based on the total weight, and more preferably 0.08 to 0.15 weight%.

[0083] The manufacturing method of the present invention features a 'three-stage temperature control process' for preventing thermal denaturation as a core feature. The manufacturing process for each stage is described in detail as follows.

[0085] Step 1 (Aqueous dissolution, Phase A): Tea tree leaf water, glycerin, a plant preservative complex, and a natural chelating agent are measured in a separate aqueous tank and heated to 75 to 80°C to dissolve uniformly. In this step, the preservative system is uniformly dispersed throughout the aqueous phase.

[0087] Step 2 (thickening agent dispersion, Phase B): Natural gum complex and low molecular weight hyaluronic acid are weighed into separate beakers and slowly divided and added, and after sufficient dispersion so as not to clump, they are added to the aqueous tank of Step 1 and stirred to complete the aqueous base.

[0089] Step 3 (Liquid crystal emulsification, Phase C): MCT oil, shea butter, liquid crystal emulsifier, olive oil complex, green tea oil, black cumin oil, watermelon seed oil, jojoba oil, neem oil, and tocopherol are weighed into an emulsification tank and heated to 75 to 80°C to dissolve uniformly.

[0090] A mixer containing an aqueous base (phases A+B) is operated at 3,000 to 4,000 rpm while slowly introducing the oil phase material and emulsifying for 10 to 15 minutes to form a solid liquid crystal structure. During this process, oil particles are finely refined, and cetearyl oliveate / sorbitan oliveate self-assembles at the interface and is trapped within a multilayer lamellar structure.

[0092] Step 4 (Post-addition of extract, Phase D): After emulsification is complete, the mixture is first cooled to 50 to 55°C. The temperature range of 50 to 55°C is optimal for maintaining the lamellar structure while preventing thermal denaturation of the physiologically active ingredients. If the temperature exceeds 55°C, effective physiologically active ingredients such as Angelica gigas, Panax ginseng, and Salicornia are destroyed; if the temperature is cooled below 50°C, the viscosity of the composition becomes excessively high, making it difficult to achieve uniform dispersion of the extract.

[0093] After reaching this temperature, the complex extract of Angelica gigas and ginseng, and the complex extract of Salicornia europaea and reed are added in sequence and mixed uniformly.

[0095] Step 5 (pH adjustment, Phase E): Citric acid (Phase E) dissolved in 1% by weight of purified water is added to adjust the pH of the final composition to a weakly acidic range of 5.0 to 6.0. By maintaining a weakly acidic pH close to the normal pH of the skin (4.5 to 5.5), the acid mantle of the skin barrier is protected and the proliferation of pathogenic bacteria is inhibited. If the pH is below 5.0, skin irritation may occur, and if it exceeds 6.0, the efficacy of the antibacterial component is reduced and the preservative function is decreased.

[0097] Step 6 (Post-addition of fragrance components, Phase F): After secondary cooling to 45°C or below, a highly volatile natural antimicrobial agent, lavender oil, thyme leaf oil, and tea tree leaf oil are added in sequence and mixed uniformly. If essential oils are added at a temperature exceeding 45°C, the main fragrance components and antimicrobial active components (linalool, thymol, terpinene-4-ol, etc.) volatilize or undergo thermal denaturation, thereby degrading their function.

[0098] After mixing is complete, vacuum degassing is performed to finish the final product.

[0100] As a result of observing the composition prepared by the above-described process under a polarizing microscope at 400x magnification, the Maltese cross pattern, which is the inherent optical anisotropy of liquid crystals, was clearly observed, confirming that a multilayer lamellar structure enveloping oil particles was firmly formed. This physically proves that the liquid crystal emulsification system of the present invention has been successfully applied.

[0102] In addition, [Fig. 1] is a photograph taken comparing the skin condition before (left) and after (right) using the cosmetic composition according to the present invention for 4 weeks. In the photograph after use, it can be visually confirmed that acne lesions and redness have been alleviated and the skin texture has been smoothed compared to before use.

[0103] These improvements are considered to be the result of the combined action of the antibacterial action of the aforementioned high-concentration tea tree leaf water base alone, the improvement of oil-water balance by jojoba oil and low molecular weight hyaluronic acid, the stable delivery of antibacterial oil components and odor masking by the liquid crystal emulsion system, and the skin barrier strengthening effect due to the lamellar structure.

[0105] As described above, although the present invention has been explained by limited embodiments, the present invention is not limited thereto, and various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

Claims

Claim 1 A liquid crystal emulsion type cosmetic composition for improving oil-water balance in acne-prone skin, comprising, based on the total weight, an aqueous base comprising 40 to 55 weight% of tea tree leaf water, which is included as a base replacing purified water and provides antibacterial and astringent effects; an antibacterial oil component comprising 0.3 to 0.7 weight% of neem oil and 1.0 to 2.0 weight% of black cumin oil; an oil-balancing component comprising 1.5 to 3.0 weight% of jojoba oil, which has a sebum-like structure and replenishes insufficient oil; a moisturizing component comprising 0.05 to 0.2 weight% of low molecular weight hyaluronic acid, which provides immediate moisture; and 4.0 to 8.0 weight% of an olive oil-derived liquid crystal emulsifier comprising cetearyl oliveate and sorbitan oliveate, which encapsulates the antibacterial oil component and the oil-balancing component in a multilayer lamellar structure to mask off-odors and prevent oxidation. Claim 2 A liquid crystal emulsion type cosmetic composition for improving oil-water balance of acne-prone skin, characterized in that, in claim 1, the composition comprises, based on the total weight, 45 to 52 weight% of tea tree leaf water, 4.5 to 6.5 weight% of liquid crystal emulsifier, 1.8 to 2.5 weight% of jojoba oil, and 0.08 to 0.15 weight% of low molecular weight hyaluronic acid. Claim 3 A method for preparing a liquid crystal emulsion type cosmetic composition for improving the oil-moisture balance of acne-prone skin according to claim 1, comprising: (a) a step of uniformly dissolving an aqueous material containing tea tree leaf water, a natural chelating agent, and glycerin by heating it to 75 to 80°C; (b) a step of completing an aqueous base by slowly adding and dispersing a natural gum complex and low molecular weight hyaluronic acid, then adding them to the aqueous material of step (a) and stirring; (c) a step of dissolving an oil phase material containing a liquid crystal emulsifier containing cetearyl oliveate and sorbitan oliveate, neem oil, black cumin seed oil, jojoba oil, and a moisturizing oil component by heating it to 75 to 80°C; and (d) an emulsification step of forming a liquid crystal with a multilayer lamellar structure by operating a mixer containing the aqueous base of step (b) at 3,000 to 4,000 rpm, while slowly adding the oil phase material of step (c) and stirring for 10 to 15 minutes. (e) a step of first cooling the result of step (d) to 50 to 55°C and then adding a plant extract complex; (f) a step of adding a pH adjuster to adjust the pH of the final composition to 5.0 to 6.0; and (g) a step of secondarily cooling the result of step (f) to 45°C or lower, then adding a fragrance additive, and finally mixing and degassing; characterized by comprising a method for preparing a liquid crystal emulsion type cosmetic composition for improving oil-water balance of acne-prone skin.

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