Cosmetic composition containing glycolipid solubilizer

Abstract

The present invention aims to provide a transparent cosmetic composition that exhibits a stable form even under high-temperature conditions. [Solution] The present invention relates to a cosmetic composition comprising sophorolipid, di-rhamnolipid, and an ionic salt, and by including the glycolipid, a transparent cosmetic composition can be provided. Furthermore, by applying the ionic salt to the composition to reduce the ionic repulsion between the glycolipid molecules, a transparent cosmetic composition with improved stability can be provided through an improved micelle packing structure.

Description

Technical Field

[0001] The present invention relates to a cosmetic composition comprising a glycolipid solubilizer. Background Art

[0002] Active research is ongoing to replace chemically synthesized ingredients in cosmetic compositions with naturally-derived ingredients in accordance with skin safety and consumer preferences. In such research, while numerous naturally-derived ingredients are available for moisturizing components and oil phase components, replacing surfactants, which are essential for the production of cosmetic compositions, with naturally-derived ingredients is considered a major obstacle. In particular, most PEG-based synthetic ingredients are used as solubilizers in transparent dosage forms, and the development of natural ingredient solubilizers to replace these is in an even more challenging situation.

[0003] As one of the natural solubilizers, glycolipids are biocompatible amphiphilic substances produced through fermentation metabolism of microorganisms. Various types of glycolipids with different sugar rings and lipid moieties depending on the carbon source and strain are produced, and exhibit different properties from each other. For example, it is possible to produce nano multi-layered liquid crystal particles having a lamellar structure by applying a glycolipid emulsifier obtained using the strain *Candida bombicola* together with a liquid crystal emulsifier (Patent Document 1). However, as disclosed in Patent Document 1, glycolipids have a limitation in that they have insufficient surface activity and are used in mixture with other synthetic emulsifiers. Furthermore, there have been no reported cases of common use thereof as a solubilizer for producing transparent dosage forms with small particles.

[0004] As another example, rhamnolipid produced using *Pseudomonas aeruginosa* is an amphiphilic substance with high hydrophilicity and excellent surface activity, and can be applied to transparently solubilize oily components in an aqueous phase. However, it has stability problems such as suspension and precipitation of the dosage form depending on environments such as temperature and pH, which makes it difficult to apply to cosmetics and achieve commercialization. Prior Art Documents [Patent Documents]

[0005] [Patent Document 1] KR10-1934788 B1 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention aims to provide a transparent cosmetic composition that exhibits a stable form even under high-temperature conditions. [Means for solving the problem]

[0007] The present invention provides a cosmetic composition comprising sophorolipid, di-rhamnolipid, and an ionic salt.

[0008] The aforementioned ionic salt may be one or more selected from the group consisting of sodium chloride (NaCl), magnesium sulfate (MgSO4), and EDTA 2NA.

[0009] The sophorolipid and diramnolipid may be included in a weight ratio of 1:1 to 15.

[0010] The ionic salt may be present in an amount of 0.1 to 2.0% by weight relative to the total weight of the composition.

[0011] The pH of the composition may be 5 to 8.

[0012] The dosage form of the composition may be selected from the group consisting of solutions, nourishing lotions, softening lotions, packs, softening waters, essences, liquid cleansers, bath additives, suspensions, gels, lotions, surfactant-containing cleansers, and sprays.

[0013] The composition may further contain one or more selected from the group consisting of pearl agents, thickeners, viscosity modifiers, pH adjusters, fatty substances, organic solvents, solvents, concentrators and gelling agents, softeners, antioxidants, suspending agents, stabilizers, foaming agents, fragrances, surfactants, water, ionic or nonionic emulsifiers, fillers, metal ion sequestering agents and chelating agents, preservatives, vitamins, blocking agents, wetting agents, essential oils, dyes, pigments, hydrophilic or lipophilic surfactants and lipid vesicles. [Effects of the Invention]

[0014] The present invention provides a transparent cosmetic composition that has improved stability at high and low temperatures without using existing synthetic surfactants, by including an ionic salt in the aqueous phase and sophorolipid and di-rhamnolipid in the solubilizing phase. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 shows the results of confirming the high-temperature stability of a composition produced according to one embodiment of the present invention, with and without (a) no ionic salt applied (Comparative Example 3) and (b) 0.5% sodium chloride applied (Example 6). [Modes for carrying out the invention]

[0016] The present invention relates to a cosmetic composition comprising sophorolipid, di-rhamnolipid, and an ionic salt.

[0017] The configuration of the present invention will be described below with specific examples.

[0018] In this invention, a micelle is generally defined as a thermodynamically stable and uniform spherical structure formed by a low molecular weight substance that is amphiphilic, for example, possessing both hydrophilic and hydrophobic groups.

[0019] In the present invention, "solubilization" means dissolving a substance with extremely low water solubility beyond its solubility using micelles formed at a concentration above a certain level when a solubilizer is dissolved in water, and a cosmetic composition in a transparent dosage form can be produced using this method.

[0020] In the present invention, the solubilizer is a surfactant used in transparent or translucent oil-in-water dosage forms containing a small amount of oil phase in a large amount of aqueous phase, and is a substance for the use of dissolving water-insoluble oil phase or fat-soluble components to form a stable phase.

[0021] Any solubilizer known in the art can be used, preferably biosurfactants or natural solubilizers may be used. For example, the solubilizer may be one or more selected from the group consisting of glycolipids, lipopeptides, phospholipids, fatty acids, neutral lipids, polymeric compounds and particulate compounds, more preferably glycolipids may be included, and still more preferably sophorolipid and di-rhamnolipid may be included.

[0022] More specifically, in the present invention, glycolipid can be used as a solubilizer. Since the glycolipid has both a hydrophilic group and a hydrophobic group, which are characteristics of amphiphilic molecules, in one molecule, it functions similarly to a surfactant at a concentration below a certain level, but when the concentration exceeds a certain level, micelles are formed and can behave in a suspended form.

[0023] In the present invention, the glycolipid refers to a compound in which a carbohydrate is bound to a lipid via a glycosidic bond. Most lipids added with sugar chains are located on the outer side of the lipid bilayer of cell membranes in eukaryotic cells, and exist in a hydrophilic environment due to the polar groups of the carbohydrates.

[0024] As an example, the glycolipid may be selected from the group consisting of sophorolipid and di-rhamnolipid.

[0025] The sophorolipid is a representative microbial biosurfactant of the glycolipid series produced by the yeast Candida bombicola.

[0026] The di-rhamnolipid is a glycolipid composed of two rhamnose units and one or two 3-hydroxy fatty acid residues, and is a biosurfactant produced by various bacterial species.

[0027] The cosmetic composition of the present invention may preferably contain both sophorolipid and di-rhamnolipid as glycolipids. In one embodiment of the present invention, when sophorolipid or di-rhamnolipid was applied alone, a transparent cosmetic could not be prepared, but when they were mixed and applied to a cosmetic, a transparent cosmetic was prepared and it was confirmed that low-temperature stability is improved.

[0028] In one specific embodiment, the solubilizer of the present invention may be contained in an amount of 0.01 to less than 10% by weight based on 100% by weight of the total composition, and preferably may be contained in an amount of 0.05 to 5% by weight. Based on 100% by weight of the total composition, when the solubilizer is contained in an amount of less than 0.01% by weight, the effect as a solubilizer becomes insignificant, and when it is contained in an amount of 10% by weight or more, a problem of dry feeling may occur in the texture of the cosmetic after use.

[0029] In the present invention, the total content of the solubilizer can be appropriately adjusted by the content of the fragrance and oil. Specifically, the total content of the solubilizer relative to the total content of the fragrance and / or oil may be in a weight ratio of 1:1 to 1:20, or in a weight ratio of 1:4 to 1:10. In the present invention, when the solubilizer is included in the aforementioned weight ratio relative to the total content of the fragrance and / or oil, it is possible to eliminate the dosage form instability that may occur due to the fragrance or oil and provide a cosmetic composition in a transparent dosage form.

[0030] Furthermore, when the solubilizing agent contains both sophorolipid and diramnolipid, the weight ratio of sophorolipid and diramnolipid may be 1:1 to 15, and more preferably 1:1 to 10.

[0031] In one embodiment, after confirming that a transparent cosmetic composition could be produced by applying the sophorolipid and diramnolipid, the stability was checked. The result showed that the transparency of the dosage form was not maintained at high temperatures and it became opaque. However, by adding an ionic salt to the composition, the high-temperature stability of the dosage form could be improved, and it was confirmed that the transparency of the dosage form was maintained at high temperatures.

[0032] From this perspective, the cosmetic composition of the present invention may contain sophorolipid, di-rhamnolipid, and an ionic salt.

[0033] The ionic salt can improve the stability of the transparent cosmetic composition through an improved micelle packing structure by reducing the ionic repulsion between the two types of glycolipid molecules.

[0034] In the present invention, the type of ionic salt is not limited, but from the perspective of low-temperature and high-temperature stability and maintaining the transparency of the dosage form, preferably one or more selected from the group consisting of sodium chloride (NaCl), magnesium sulfate (MgSO4), and EDTA 2Na may be used.

[0035] In one specific example, the ionic salt may be present in an amount of 0.1 to 2.0% by weight of the total cosmetic composition of the present invention, preferably 0.1 to 1.5% by weight, and more preferably 0.2 to 1.0% by weight. When present within this range, the stability of the transparent cosmetic is improved through an improved micelle packing structure by reducing ionic repulsion between the two types of glycolipid molecules contained in the cosmetic composition.

[0036] In the present invention, when a complex compound of EDTA and Na is used as the ionic salt, the composition of the present invention can have a pH of 2.69 to 8, preferably 5 to 8, and more preferably 5 to 6.13. This is advantageous because an appropriate amount of Na+ salt is released by EDTA, ensuring transparency of the dosage form and low and high temperature stability.

[0037] The cosmetic composition according to the present invention may be a transparent or translucent composition, but preferably a transparent composition.

[0038] By including sophorolipid and di-rhamnolipid according to the present invention in a certain weight ratio, it is possible to provide a transparent cosmetic composition with improved stability without using excessive amounts of ethanol or synthetic surfactants such as PEG series, which have been conventionally used to realize a transparent dosage form.

[0039] In the present invention, "transparent" or "translucent" refers to a dosage form produced when the refractive index of the aqueous phase and the solubilized phase is adjusted so that the refractive index difference between the aqueous phase and the solubilized phase is 0.005 or less.

[0040] In the present invention, "stability" refers to the stability of a transparent cosmetic composition, and means the degree to which the composition remains stable in terms of suspension, precipitation, etc., under environmental conditions such as temperature and pH that may occur when a microbial surfactant or natural solubilizer is transparently solubilized in the aqueous phase.

[0041] The cosmetic composition according to the present invention may have a dosage form selected from the group consisting of solutions, nourishing lotions, softening lotions, packs, softening waters, essences, liquid cleansers, bath additives, suspensions, gels, lotions, surfactant-containing cleansers, and sprays.

[0042] In the present invention, the cosmetic composition may further include auxiliaries and carriers commonly used in the field of cosmetics, such as pearlescent agents, thickeners, viscosity modifiers, pH adjusters, fatty substances, organic solvents, solvents, concentrates and gelling agents, softeners, antioxidants, suspending agents, stabilizers, foaming agents, fragrances, surfactants, water, ionic or nonionic emulsifiers, fillers, metal ion sequestering agents and chelating agents, preservatives, vitamins, blocking agents, wetting agents, essential oils, dyes, pigments, hydrophilic or lipophilic surfactants, lipid vesicles, or any other components commonly used in cosmetics.

[0043] The cosmetic composition according to the present invention has improved surfactant ability of glycolipids, which transparently solubilizes oil phase components including fragrances and oils, and by including ionic salts, it is possible to provide a cosmetic composition with a stable and differentiated feel that maintains transparency at high and low temperatures.

[0044] In the present invention, "low-temperature stability" means that when an ionic salt is added to the cosmetic composition, the stability of the transparent cosmetic composition based on the ionic salt content is confirmed at a temperature of 0°C.

[0045] The present invention will now be described in detail through examples. The following examples are illustrative of the present invention and do not limit the scope of the present invention. These examples are provided to ensure a complete disclosure of the present invention and to fully inform those with ordinary skill in the art to which the present invention pertains, and the present invention is defined by the scope of the claims.

[0046] In the experimental example below, the transparency of the dosage form was confirmed by visual observation 24 hours after manufacturing, checking for transparency and phase separation; low-temperature stability was confirmed by visual observation after leaving the dosage form at 0°C for one week immediately after manufacturing; and high-temperature stability was confirmed by visual observation after leaving it at 50°C for one week.

[0047] Experimental Example 1: Production of a transparent cosmetic composition using glycolipids

[0048] [Table 1]

[0049] The solubilizing portion was heated to 45°C and stirred with the composition shown in Table 1, and the stirred solubilizing portion was gradually added to the aqueous phase at room temperature and stirring conditions of 800 rpm to produce the cosmetic. The content of each component in Table 1 is shown as weight percent based on 100% by weight of the total cosmetic.

[0050] Experimental Example 1-1: Confirmation and evaluation of the stability of transparent cosmetic production using glycolipids.

[0051] [Table 2]

[0052] As can be seen from Table 2 above, when a glycolipid solubilizer is applied alone, a transparent cosmetic is not produced. However, when sophorolipid and diramnolipid are used together, it was confirmed that a stable and transparent dosage form can be obtained at low temperatures. However, since the dosage form becomes opaque at high temperatures, dosage form conditions to improve high-temperature stability were investigated.

[0053] Experimental Example 2: Production of a transparent cosmetic composition using ionic salts

[0054] [Table 3]

[0055] Each cosmetic composition was manufactured using the manufacturing method described in Experimental Example 1, with the compositions shown in Table 3 differing only in whether or not sodium chloride was included in the aqueous phase. The content of each component in Table 3 is shown in weight percent based on 100% of the total cosmetic composition. The stability of the compositions manufactured according to each composition was confirmed and is shown in Table 4 below.

[0056] Experimental Example 2-1: Confirmation of the production and evaluation of the stability of transparent cosmetic compositions based on ionic salt content.

[0057] [Table 4]

[0058] As shown in Table 4 above, it can be confirmed that Examples 5-7, in which sodium chloride ion salts were applied, all exhibited excellent transparency of the dosage form at both low and high temperatures.

[0059] Furthermore, as shown in Figure 1, observation of the samples from Comparative Example 3 and Example 6 under high-temperature conditions confirmed that Comparative Example 3, which did not contain salt, exhibited an opaque dosage form at high temperatures.

[0060] Experimental Example 3: Production of transparent cosmetic compositions depending on the type of ionic salt

[0061] [Table 5]

[0062] Each cosmetic composition, with different ionic salts according to the composition shown in Table 5, was manufactured using the manufacturing method described in Experimental Example 1. The changes in the compositions produced by each composition are shown in Table 6 below.

[0063] Experimental Example 3-1: Confirmation of the manufacturing process and evaluation of the stability of transparent cosmetic compositions based on the type of ionic salt.

[0064] [Table 6]

[0065] As shown in Table 6 above, Examples 8 and 9, which applied magnesium sulfate and EDTA 2Na ion salt, were found to be even more advantageous in that the transparency of the dosage form was maintained at both low and high temperatures.

Claims

1. A cosmetic composition characterized by containing sophorolipid, di-rhamnolipid, and an ionic salt.

2. The aforementioned ionic salts are sodium chloride (NaCl) and magnesium sulfate (MgSO4). ４ The cosmetic composition according to claim 1, characterized in that it is one or more selected from the group consisting of ) and EDTA 2Na.

3. The cosmetic composition according to claim 1, characterized in that the sophorolipid and diramnolipid are contained in a weight ratio of 1:1 to 15.

4. The cosmetic composition according to claim 1, characterized in that the ionic salt is contained in an amount of 0.1 to 2.0% by weight relative to the total weight of the composition.

5. The cosmetic composition according to claim 1, characterized in that the pH of the composition is 5 to 8.

6. The cosmetic composition according to claim 1, characterized in that the dosage form of the composition is selected from the group consisting of solution, nourishing lotion, softening lotion, pack, softening water, essence, liquid cleanser, bath additive, suspension, gel, lotion, surfactant-containing cleanser, and spray.

7. The cosmetic composition according to claim 1, further comprising one or more selected from the group consisting of pearlescent agents, thickeners, viscosity modifiers, pH adjusters, fatty substances, organic solvents, solvents, concentrates and gelling agents, softeners, antioxidants, suspending agents, stabilizers, foaming agents, fragrances, surfactants, water, ionic or nonionic emulsifiers, fillers, metal ion sequestering agents and chelating agents, preservatives, vitamins, blocking agents, wetting agents, essential oils, dyes, pigments, hydrophilic or lipophilic surfactants and lipid vesicles.

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