Preparation of solid lipid microcapsule sun-screening agent and application of solid lipid microcapsule sun-screening agent in cosmetics

Abstract

The invention relates to the technical field of cosmetics, in particular to preparation of a solid lipid microcapsule sun-screening agent and application of the solid lipid microcapsule sun-screening agent in cosmetics. The preparation method comprises the following steps: S1, pretreatment of a chemical sun-screening agent: dissolving and uniformly stirring lipid, an emulsifier, a crystalline sun-screening agent and a solvent at 72-78 DEG C to obtain a uniformly dispersed oil phase, the lipid is 2-5% of polyglycerol-10 stearate, the specific amount of the lipid is 3%, the emulsifier is 4-6% of stearyl alcohol polyether-21, the specific amount of the emulsifier is 5%, the specific amount of the solvent is 3%, the specific amount of the solvent is 3%, and the specific amount of the solvent is 5%; the sun-screening agent is prepared from the following components in percentage by weight: 7%-9% of bis-ethyl hexyloxyphenol methoxyphenyl triazine and 7%-9% of ethyl hexyltriazinone. According to the preparation of the solid lipid microcapsule sun-screening agent and the application of the solid lipid microcapsule sun-screening agent in cosmetics, the solid lipid microcapsule sun-screening agent is adopted and has excellent formula stability, safety and efficient sun-screening capacity, the sticky feeling of the sun-screening agent on the skin surface is effectively reduced, and the use experience feeling of a product is improved.

Description

Technical Field

[0001] The invention relates to the technical field of cosmetics, in particular to the preparation of a solid lipid microcapsule sunscreen and the application of the same in cosmetics. Background Art

[0002] Chemical sunscreen products made with existing technology will gradually be oxidized while absorbing ultraviolet rays. Therefore, the sunscreen effect will gradually weaken over time. Salicylic acid, para-aminobenzoic acid, and cinnamic acid in chemical sunscreens are easily absorbed by the skin after application, posing a safety hazard. The higher the sun protection factor of a chemical sunscreen, the longer the sun protection time and the better the sunscreen effect. However, to achieve a relatively high index, a large amount of sunscreen is usually required to be added, which may cause the skin to feel more oily, affect skin metabolism, and even cause other skin diseases.

[0003] Sunscreen is the most important topic of skin protection in the field of cosmetics, and the stability, safety and efficiency of sunscreen are the core of the quality of sunscreen products. Chemical sunscreen absorbs UVA and UVB bands in ultraviolet rays and converts ultraviolet light energy into heat or other forms of energy, thereby reducing the direct damage of ultraviolet rays to the skin and achieving the purpose of sunscreen. Since most chemical sunscreens are gradually oxidized while absorbing ultraviolet rays, the sunscreen effect will gradually weaken over time and can be absorbed through the skin. They are not safe and have a strong sticky feeling after application. The user experience is not very good and is rejected by the public. Therefore, it is very necessary to use new processes or technologies to make sunscreens, reduce the irritation of sunscreen products, and enhance the effectiveness and pleasure of using sunscreen products. Summary of the invention

[0004] The object of the present invention is to provide a preparation method of a solid lipid microcapsule sunscreen and its application in cosmetics to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a solid lipid microcapsule sunscreen, comprising the following steps; S1. Preparation of pre-treatment of chemical sunscreens The lipids, emulsifiers, crystalline sunscreen agents and solvents are dissolved and stirred evenly at 72-78°C to obtain a uniformly dispersed oil phase. The solvent is isoamyl p-methoxycinnamate, which is oil-soluble and insoluble in water. It has a strong solubility for crystalline components, accounting for 22%-26%, specifically 24%.

[0006] The lipid described above is polyglycerol-10 stearate in a ratio of 2%-5%, specifically 3%, the emulsifier is steareth-21 in a ratio of 4%-6%, specifically 5%, the sunscreen agent is bis-ethylhexyloxyphenol methoxyphenyl triazine in a ratio of 7%-9%, ethylhexyl triazone in a ratio of 7%-9%, glycerol in a ratio of 5%, para-hydroxyacetophenone in a ratio of 0.5%-1%, specifically 0.8%, and 1.2-hexanediol in a ratio of 0.5%-1%, specifically 0.8%.

[0007] S2. Preparation of aqueous phase system The aqueous phase consisting of the humectant and deionized water is heated to 75-84° C. to obtain a uniformly dispersed aqueous phase.

[0008] The above-mentioned moisturizing agent is 4%-10% glycerol, and deionized water is added to 100%.

[0009] S3, homogenized emulsified water phase and oil phase The water phase obtained in S2 is homogenized at a rotation speed of 1500-1800 RPM, and the oil phase system obtained in S1 is added at the same time, and homogenized for 21-40 minutes; an emulsified crude material is obtained, and the material is reserved for later use.

[0010] S4. Ultrasonic emulsification promotes the dispersion of emulsion droplets The emulsified crude liquid obtained in S3 is dispersed at high speed under high-frequency ultrasound to obtain a water-in-oil solid lipid microcapsule sunscreen preformed liquid, and the material is kept for later use.

[0011] S5, micro jet high pressure dispersion, promote further dispersion of droplets The prefabricated liquid obtained in S4 was dispersed at high speed under high-frequency ultrasound to obtain a microcapsule sunscreen. The particle size of the microcapsule was measured. At a content of 0.1%, the particle size of the microcapsule was 200-500nm, and the finished product was obtained.

[0012] Preferably, the sample needs to be tested, and the following steps are required during the test: S1.1 uses a fully automatic coating platform and coater to repeatedly coat sunscreen samples on quartz sheets of precise thickness, obtaining multiple sheets of sunscreen sample coatings with good reproducibility and precise coating thickness. The coating detection comparison thickness is 5 microns.

[0013] S1.2 Measure the absorption curve of the coating sample using a UV-visible spectrophotometer and record the absorption values ​​between 290 nm and 400 nm.

[0014] S1.3 Use HPA skin care lamp to simulate sunlight irradiation on the coating sample. The lamp source energy is 6.7 mW / cm2, and the irradiation dose is equivalent to the amount of sunlight irradiation for one hour at noon in summer at 31 degrees north latitude.

[0015] S1.4 After irradiation, use a UV-visible spectrophotometer to measure the sample coating absorption curve, substitute the measured value into the ISO24443 calculation formula to calculate the sample SPF value and PA value.

[0016] Preferably, in S4, a solid lipid microcapsule sunscreen preformed liquid is obtained, and the solid lipid nanoparticles in the preformed liquid are solidified and crystallized to form a solid structure during cooling or phase separation using solid oils.

[0017] Preferably, the operation in S1.3 can compare the photostability of the solid lipid system and the common emulsified system. The outstanding photostability can significantly improve the photostability of photosensitivity chemical sunscreens in the formula. The loss of sunscreens under the same light is significantly reduced. At the same time, the UV absorption efficiency can be detected to be higher than that of free sunscreens. Taking both AB bands into account, the solid lipid system obviously has a stronger UV absorption ability.

[0018] Preferably, the test data in S1.4 is as follows: Test sample: QQB23011002 (OrdsunPro STE 30%, O / W emulsion).

[0019] Test conditions: PMMA HD6 plate, coating amount 1.3mg / cm².

[0020] Testing instrument: UV-2000S.

[0021] Test results: OrdsunPro STE emulsion has excellent high stability. Figure 1 It can be seen that the SPF value of 0rdsunPro STE sunscreen lotion remains basically unchanged after being placed at 50℃ for one month.

[0022] Preferably, the solid lipid nanoparticles in S4 are encapsulated by the components and are coated in the lipid structure during the solidification and crystallization process. The solid lipid nanoparticles have a small particle size and have an adhesion effect on the solid surface. The smaller the particle size, the stronger the adhesion effect, and a good closed system can be formed on the skin.

[0023] A use of a solid lipid microcapsule sunscreen in cosmetics, wherein the solid lipid microcapsule sunscreen is prepared by any of the above-mentioned solid lipid microcapsule sunscreen preparation methods, and when used in an O / W cream or spray formula, the solid lipid microcapsule sunscreen is directly added to the system when the solid lipid microcapsule sunscreen is cooled to about 40°C and stirred evenly; When used in W / O type formulations, add directly to the water phase and then emulsify at temperatures below 50°C.

[0024] Compared with the prior art, the present invention has the following beneficial effects: 1. The preparation of the solid lipid microcapsule sunscreen and its application in cosmetics, using the solid lipid microcapsule sunscreen, has excellent formula stability, safety and high-efficiency sun protection ability (SPF).

[0025] 2. The preparation of the solid lipid microcapsule sunscreen and its application in cosmetics. The use of the solid lipid microcapsule sunscreen can effectively reduce the sticky feeling of the sunscreen on the skin surface and enhance the product usage experience.

[0026] 3. The preparation of the solid lipid microcapsule sunscreen and its application in cosmetics. The preparation method is simple, has no requirements on product consistency, has low restrictions on the reactor, has broad market prospects, and is suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a schematic diagram of the change in SPF value of the OrdsunPro STE emulsion of the present invention after being placed at 50°C for one month; Figure 2 It is a schematic diagram of the coating process using a fully automatic coating platform and a coater of the present invention; Figure 3 This is a schematic diagram of the results of calculating the SPF value and PA value of the sample of the present invention; Figure 4 It is a schematic diagram comparing the photostability of the solid lipid system of the present invention and a common emulsification system; Figure 5 It is a schematic diagram showing the comparative structure of the absorbance of the solid lipid nanoparticles of the present invention and the ethanol solution of the sunscreen agent to ultraviolet rays; Figure 6 This is a schematic diagram of the recommended usage of OrdsunPro STE of the present invention in various formulations. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] See also Figure 1-6 , the present invention provides the following technical solutions: A method for preparing a solid lipid microcapsule sunscreen comprises the following steps: S1. Preparation of pre-treatment of chemical sunscreens The lipids, emulsifiers, crystalline sunscreen agents and solvents are dissolved and stirred evenly at 72-78°C to obtain a uniformly dispersed oil phase. The solvent is isoamyl p-methoxycinnamate, which is oil-soluble and insoluble in water. It has a strong solubility for crystalline components, accounting for 22%-26%, specifically 24%.

[0032] The lipid described above is polyglycerol-10 stearate in a ratio of 2%-5%, specifically 3%, the emulsifier is steareth-21 in a ratio of 4%-6%, specifically 5%, the sunscreen agent is bis-ethylhexyloxyphenol methoxyphenyl triazine in a ratio of 7%-9%, ethylhexyl triazone in a ratio of 7%-9%, glycerol in a ratio of 5%, para-hydroxyacetophenone in a ratio of 0.5%-1%, specifically 0.8%, and 1.2-hexanediol in a ratio of 0.5%-1%, specifically 0.8%.

[0033] S2. Preparation of aqueous phase system The aqueous phase consisting of the humectant and deionized water is heated to 75-84° C. to obtain a uniformly dispersed aqueous phase.

[0034] The above-mentioned moisturizing agent is 4%-10% glycerin, and deionized water is added to 100%.

[0035] S3, homogenized emulsified water phase and oil phase The water phase obtained in S2 is homogenized at a rotation speed of 1500-1800 RPM, and the oil phase system obtained in S1 is added at the same time, and homogenized for 21-40 minutes; an emulsified crude material is obtained, and the material is reserved for later use.

[0036] S4. Ultrasonic emulsification promotes the dispersion of emulsion droplets The emulsified crude liquid obtained by S3 is dispersed at high speed under high-frequency ultrasound to obtain a water-in-oil solid lipid microcapsule sunscreen preformed liquid. The material is kept for later use to obtain a solid lipid microcapsule sunscreen preformed liquid. The solid lipid nanoparticles in the preformed liquid are solidified and crystallized during cooling or phase separation to form a solid structure. The encapsulated components of the solid lipid nanoparticles are coated in the lipid structure during the solidification and crystallization process. The solid lipid nanoparticles have a small particle size and have an adhesion effect on the solid surface. The smaller the particle size, the stronger the adhesion effect, and a good closed system can be formed on the skin.

[0037] S5, micro jet high pressure dispersion, promote further dispersion of droplets The prefabricated liquid obtained in S4 was dispersed at high speed under high-frequency ultrasound to obtain a microcapsule sunscreen. The particle size of the microcapsule was measured. At a content of 0.1%, the particle size of the microcapsule was 200-500nm, and the finished product was obtained.

[0038] The samples need to be tested, and the following steps are required for testing: S1.1 uses a fully automatic coating platform and coater to repeatedly coat sunscreen samples on quartz sheets of precise thickness, obtaining multiple sheets of sunscreen sample coatings with good reproducibility and precise coating thickness. The coating detection comparison thickness is 5 microns.

[0039] S1.2 Measure the absorption curve of the coating sample using a UV-visible spectrophotometer and record the absorption values ​​between 290 nm and 400 nm.

[0040] S1.3 uses HPA skin care lamp to simulate sunlight irradiation on the coating sample. The lamp energy is 6.7 mW / cm2, and the irradiation dose is equivalent to the amount of sunlight irradiation in one hour at noon in summer at 31 degrees north latitude. The photostability of solid lipid system and ordinary emulsification system can be compared. The outstanding photostability can significantly improve the photostability of photosensitivity chemical sunscreen in the formula. The loss of sunscreen is significantly reduced under the same light. At the same time, it can detect that the UV absorption efficiency is higher than that of free sunscreen. Taking into account both AB bands, the solid lipid system obviously has a stronger UV absorption ability.

[0041] S1.4 After irradiation, use a UV-visible spectrophotometer to measure the sample coating absorption curve, substitute the measured value into the ISO24443 calculation formula, and calculate the sample SPF value and PA value. The test data is as follows: Test sample: QQB23011002 (OrdsunPro STE 30%, O / W emulsion).

[0042] Test conditions: PMMA HD6 plate, coating amount 1.3mg / cm².

[0043] Testing instrument: UV-2000S.

[0044] Test results: OrdsunPro STE emulsion has excellent high stability. Figure 1 It can be seen that the SPF value of 0rdsunPro STE sunscreen lotion remains basically unchanged after being placed at 50℃ for one month.

[0045] A use of a solid lipid microcapsule sunscreen in cosmetics, wherein the solid lipid microcapsule sunscreen is prepared by any of the above-mentioned solid lipid microcapsule sunscreen preparation methods, and when used in an O / W cream and spray formula, the solid lipid microcapsule sunscreen is directly added to the system when it is finally cooled to about 40°C and stirred evenly; When used in W / O type formulations, add directly to the water phase and then emulsify. Emulsify below 50°C. Ordsun ProSTE is a water dispersion system that can be easily applied to various O / W and W / O formulations. The recommended usage in various formulations is as follows: Figure 6 shown.

[0046] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a solid lipid microcapsule sunscreen, characterized in that: The steps include: S1. Preparation of pre-treatment of chemical sunscreens Dissolve lipids, emulsifiers, crystalline sunscreens, and solvents at 72-78°C and stir evenly to obtain a uniformly dispersed oil phase. The solvent is isoamyl p-methoxycinnamate, which is oil-soluble and insoluble in water. It has a strong solubility for crystalline components, accounting for 22%-26%, specifically 24%; The lipid is polyglycerol-10 stearate in a ratio of 2%-5%, specifically 3%, the emulsifier is steareth-21 in a ratio of 4%-6%, specifically 5%, the sunscreen is bis-ethylhexyloxyphenol methoxyphenyl triazine in a ratio of 7%-9%, ethylhexyl triazone 7%-9%, glycerin 5%-8%, p-hydroxyacetophenone 0.5%-1%, specifically 0.8%, 1.2-hexanediol 0.5%-1%, specifically 0.8%; S2. Preparation of aqueous phase system The water phase consisting of the moisturizer and deionized water is heated to 75-84°C to obtain a uniformly dispersed water phase; The above-mentioned moisturizing agent is 4%-10% glycerol, and deionized water is added to 100%; S3, homogenized emulsified water phase and oil phase Homogenize the water phase obtained in S2 at a speed of 1500-1800 RPM, and add the oil phase system obtained in S1 at the same time, and homogenize for 21-40 minutes to obtain an emulsified crude material, which is reserved for later use; S4. Ultrasonic emulsification promotes the dispersion of emulsion droplets The emulsified crude liquid obtained in S3 is dispersed at high speed under high-frequency ultrasound to obtain a preformed liquid of an oil-in-water solid lipid microcapsule sunscreen agent, and the material is kept for later use; S5, micro jet high pressure dispersion, promote further dispersion of droplets The prefabricated liquid obtained in S4 was dispersed at high speed under high-frequency ultrasound to obtain a microcapsule sunscreen. The particle size of the microcapsule was measured. At a content of 0.1%, the particle size of the microcapsule was 200-500nm, and the finished product was obtained.

2. The method for preparing a solid lipid microcapsule sunscreen according to claim 1, characterized in that: The samples need to be tested, and the following steps are required for testing: S1.1 uses a fully automatic coating platform and coater to repeatedly coat sunscreen samples on quartz sheets of precise thickness, obtaining multiple sheets of sunscreen sample coatings with good reproducibility and precise film thickness. The film detection comparison thickness is 5 microns; S1.2 Measure the absorption curve of the coating sample using a UV-visible spectrophotometer and record the absorption values ​​between 290 nm and 400 nm; S1.3 Use HPA skin care lamp to simulate sunlight irradiation on the coating sample. The lamp source energy is 6.7 mW / cm2, and the irradiation dose is equivalent to the solar radiation of 1 hour at noon in summer at 31 degrees north latitude; S1.4 After irradiation, use a UV-visible spectrophotometer to measure the sample coating absorption curve, substitute the measured value into the ISO24443 calculation formula to calculate the sample SPF value and PA value.

3. The method for preparing a solid lipid microcapsule sunscreen according to claim 2, characterized in that: In the S4, a solid lipid microcapsule sunscreen preformed liquid is obtained, and the solid lipid nanoparticles in the preformed liquid are solidified and crystallized to form a solid structure during cooling or phase separation by solid oil.

4. The method for preparing a solid lipid microcapsule sunscreen according to claim 3, characterized in that: The operation in S1.3 can compare the photostability of the solid lipid system and the common emulsified system. The outstanding photostability can significantly improve the photostability of photosensitivity chemical sunscreens in the formula. The loss of sunscreens under the same light is significantly reduced. At the same time, it can be detected that the UV absorption efficiency is higher than that of free sunscreens. Taking into account both AB bands, the solid lipid system obviously has a stronger UV absorption ability.

5. The method for preparing a solid lipid microcapsule sunscreen according to claim 4, characterized in that: The test data in S1.4 are as follows: Test sample: QQB23011002 (OrdsunPro STE 30%, O / W emulsion); Test conditions: PMMA HD6 plate, smearing amount 1.3mg / cm²; Test instrument: UV-2000S; Test results: The lotion containing Ordsun Pro STE has excellent high stability. According to Figure 1, it can be seen that the SPF value of the sunscreen lotion containing Ordsun Pro STE remains basically unchanged after being placed at 50°C for one month.

6. The preparation of a solid lipid microcapsule sunscreen according to claim 5 and its application in cosmetics, characterized in that: The solid lipid nanoparticles in S4 are encapsulated by the components and coated in the lipid structure during the solidification and crystallization process. The solid lipid nanoparticles have a small particle size and have an adhesion effect on the solid surface. The smaller the particle size, the stronger the adhesion effect, and a good closed system can be formed on the skin.

7. Application of a solid lipid microcapsule sunscreen in cosmetics, characterized in that: The solid lipid microcapsule sunscreen is prepared by the solid lipid microcapsule sunscreen preparation method according to any one of claims 1 to 6.

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