A kind of organic silicon elastomer gel for skin care products and preparation method thereof

Abstract

The present invention relates to the technical field of polymer compounds, and provides a silicone elastomer gel for skin care products and a preparation method thereof. The silicone elastomer gel comprises: a gel matrix, the gel matrix comprises a silicone elastomer, a cross-linking agent, a thickener and a solvent; microcapsules, the microcapsules are dispersed in the three-dimensional network structure of the gel matrix, and the microcapsules include a core material and a wall material; the wall material wraps the core material, the core material includes a moisturizing component, and the wall material includes a phase change component. The present invention combines silicone elastomer gel and microcapsule technology to improve the skin care effect while avoiding greasy feeling and enhancing the long-lasting skin care properties of the product; the silicone elastomer gel forms a protective film, effectively locks in moisture, and prolongs the moisturizing effect; at the same time, the wall material of the microcapsule contains a phase change component, which responds to changes in external temperature, adjusts the core material to continuously and stably release moisturizing components, and improves skin comfort.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer compounds, and in particular to an organic silicon elastomer gel for skin care products and a preparation method thereof. Background Art

[0002] At present, most skin care products on the market use water-based or oil-based formulas. Although these formulas can provide a certain moisturizing effect, they have some obvious shortcomings. The water in water-based skin care products evaporates quickly, resulting in a short-lasting moisturizing effect, and users often need to replenish it frequently. Oil-based skin care products are prone to leave a greasy feeling on the skin surface, which may cause discomfort, especially in hot weather or for users with oily skin.

[0003] Silicone materials are mainly used to improve the touch and spreadability of skin care products. They are usually added to the basic formula as an auxiliary ingredient to enhance the product experience. However, the use of silicone materials alone is not enough to solve the problem of the sustainability of moisturizing and repairing effects. Therefore, how to improve the skin care effect while avoiding greasy feeling and improving the long-term effectiveness of the product is still a major challenge in the current research and development of skin care formulas. Summary of the invention

[0004] The present invention provides a silicone elastomer gel for skin care products and a preparation method thereof. By combining the silicone elastomer gel and microcapsule technology, the skin care effect is improved while avoiding greasy feeling and enhancing the long-lasting skin care properties of the product; the silicone elastomer gel forms a protective film to effectively lock in moisture and prolong the moisturizing effect, and the microcapsules wrap the moisturizing ingredients and phase change ingredients to achieve controlled release, improve the stability of the ingredients and release them continuously, thereby ensuring a long-lasting skin care effect; in addition, the good compatibility of the wall material of the microcapsule with the silicone gel matrix solves the problems of incompatibility between the ingredients and poor storage stability.

[0005] To solve the above problems, a first object of the present invention is to provide a silicone elastomer gel for skin care products.

[0006] The second object of the present invention is to provide a method for preparing a silicone elastomer gel for skin care products.

[0007] To achieve the first purpose of the present invention, the present invention provides a silicone elastomer gel for skin care products, the silicone elastomer gel comprising: a gel matrix, the gel matrix comprising a silicone elastomer, a cross-linking agent, a thickener and a solvent; microcapsules, the microcapsules are dispersed in the three-dimensional network structure of the gel matrix, and the microcapsules include a core material and a wall material; wherein the wall material wraps the core material, the core material includes a moisturizing component, and the wall material includes a phase change component.

[0008] In a technical solution of the present invention, the phase transformation is to form a modified acrylic ester copolymer, and the number average molecular weight of the modified acrylic ester copolymer is between 10000-50000 g / mol.

[0009] In one technical solution of the present invention, the silicone elastomer gel comprises the following components in parts by mass: silicone elastomer: 15-30 parts; cross-linking agent: 0.5-5 parts; thickener: 0.1-2 parts; solvent: 60-80 parts; phase change component: 1-2 parts; moisturizing component: 5-8 parts; wall material: 6-30 parts.

[0010] To achieve the second object of the present invention, the present invention provides a method for preparing a silicone elastomer gel for skin care products, comprising the following steps:

[0011] S100, adding an organosilicon elastomer, a crosslinking agent, and a thickener into a solvent, and stirring the mixture to obtain a gel matrix;

[0012] S200, dispersing the moisturizing component in deionized water and performing a heating treatment to obtain a core material; after uniformly mixing the phase change component with the wall material, coating the surface of the core material by a spray drying method to obtain a microcapsule;

[0013] S300, adding the microcapsules into the gel matrix, and mixing them evenly to obtain the silicone elastomer gel.

[0014] In a technical solution of the present invention, S100 specifically includes: S111, adding a silicone elastomer to a solvent, heating to 70-90°C for a first stirring treatment to obtain a first solution; S112, adding a crosslinking agent to the first solvent, performing a crosslinking reaction at 80-120°C for 30-60 minutes to obtain a second solution; S113, adding a thickener to the second solution, performing a second stirring treatment to obtain a gel matrix.

[0015] In a technical solution of the present invention, in S111, the solvent includes at least one of deionized water, ethanol, and propylene glycol; and / or in S111, the rotation speed range of the first stirring treatment is between 300-500 rpm, and the time is between 15-30 min; and / or in S111, the rotation speed range of the second stirring treatment is between 200-400 rpm, and the time is between 15-30 min; and / or in S112, the cross-linking agent includes at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, phenyltriethoxysilane, and phenyltrimethoxysilane; and / or in S113, the thickener includes at least one of polyvinyl alcohol and sodium carboxymethyl cellulose.

[0016] In a technical solution of the present invention, S200 specifically includes: S210, adding a surfactant to the moisturizing component, dispersing it in deionized water with a temperature between 50-80°C, adding a binder, and heating it at 60-80°C for 30-60min to obtain a core material; S220, adding chitosan to deionized water, adding citric acid dropwise at 60-80°C, and stirring it until it is completely dissolved, adding a phase change component after dissolution, and mixing it evenly to obtain a wall material; S230, adding the wall material dropwise into the core material and stirring it synchronously, after the dropwise addition is completed, homogenizing the core material and the wall material under ultrasonic conditions of 40-60kHz for 10-30min to obtain a mixed solution; S240, sending the mixed solution to a spray dryer, the inlet temperature of the spray dryer is between 100-160°C, and the outlet temperature is between 50-80°C, and microcapsule particles are obtained by spray drying; S250, washing the microcapsule particles and centrifuging them to obtain microcapsules.

[0017] In a technical solution of the present invention, in S10, the moisturizing component includes at least one of hyaluronic acid and glycerol; and / or in S220, the adhesive includes at least one of gelatin and polyvinyl alcohol; and / or in S250, the centrifugal treatment time is between 30-60 minutes.

[0018] In one technical solution of the present invention, in S210, the phase change is to form a modified acrylic copolymer, and the preparation method of the modified acrylic copolymer comprises the following steps: S211, methyl acrylate, acrylic vinyl ether, ethyl acrylate, and polyvinyl alcohol are mixed and dissolved in ethanol, a plasticizer and an initiator are added, a polymerization reaction is carried out, and a phase change composition is obtained after cooling.

[0019] In a technical solution of the present invention, in S300, the temperature during the mixing process is controlled between 20-40°C, and the time is controlled between 30-60 minutes.

[0020] After adopting the technical solution of the present invention, the following technical effects can be achieved:

[0021] (1) Through microencapsulation technology, the gel can continuously and stably release moisturizing ingredients to help maintain the skin's hydration effect. At the same time, the wall material of the microcapsule contains phase-changing components that respond to changes in external temperature and adjust the core material to continuously and stably release moisturizing ingredients, thereby improving skin comfort.

[0022] (2) The silicone elastomer gel of the present application forms a soft protective film that can effectively lock in moisture and resist the invasion of harmful substances in the external environment, thereby enhancing the skin barrier function. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention are described clearly and completely. 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 creative work are within the scope of protection of the present invention.

[0024] At present, most skin care products on the market use water-based or oil-based formulas. Although these formulas can provide a certain moisturizing effect, they have some obvious shortcomings. The water in water-based skin care products evaporates quickly, resulting in a short-lasting moisturizing effect, and users often need to replenish it frequently. Oil-based skin care products are prone to leave a greasy feeling on the skin surface, which may cause discomfort, especially in hot weather or for users with oily skin.

[0025] Silicone materials are mainly used to improve the touch and spreadability of skin care products. They are usually added to the basic formula as an auxiliary ingredient to enhance the product experience. However, the use of silicone materials alone is not enough to solve the problem of the sustainability of moisturizing and repairing effects. Therefore, how to improve the skin care effect while avoiding greasy feeling and improving the long-term effectiveness of the product is still a major challenge in the current research and development of skin care formulas.

[0026] The present invention provides a silicone elastomer gel for skin care products and a preparation method thereof. By combining the silicone elastomer gel and microcapsule technology, the skin care effect is improved while avoiding greasy feeling, thereby enhancing the long-lasting skin care properties of the product; the silicone elastomer gel forms a protective film, effectively locks in moisture, and prolongs the moisturizing effect; at the same time, the wall material of the microcapsule contains a phase change component, which responds to changes in external temperature and adjusts the core material to continuously and stably release the moisturizing component, thereby improving skin comfort; in addition, the good compatibility of the wall material of the microcapsule with the silicone gel matrix solves the incompatibility problem between the components.

[0027] The wall material of the microcapsule contains a phase-changing component, which is a modified acrylic copolymer. By introducing different flexible monomers, the glass transition temperature of the polymer can be adjusted to be close to 37°C (i.e., human skin temperature). That is to say, after being applied to the skin, when the polymer changes from solid to liquid or other states, the wall material of the microcapsule will be subjected to stress changes, thereby "opening" or becoming thinner, releasing the moisturizing ingredients therein, so that it can be activated after contact with the skin to ensure the release of the moisturizing ingredients on demand.

[0028] Moisturizing ingredients include hyaluronic acid, glycerin, plant extracts, etc., which are usually highly hydrophilic. They can combine with water on the skin surface to maintain hydration. These ingredients are slowly released through the rupture of the wall material of the microcapsule to maintain a continuous moisturizing effect. When the microcapsule comes into contact with the skin, the wall material of the microcapsule will gradually rupture under the action of water, as well as the temperature rise, physical state change and volume change of the phase change material, thereby slowly releasing the moisturizing ingredients. The thickness of the wall material of the microcapsule determines the release rate and duration of the moisturizing ingredients. Thinner wall materials will release faster, while thicker wall materials can achieve longer sustained release. Therefore, the preferred particle size of the microcapsule is between 1-10 microns, and the thickness of the wall material is between 0.1-2 microns.

[0029] Silicone elastomer gel has good biocompatibility and flexibility, and can form a soft protective film on the skin surface, thereby locking in the skin's moisture. It can also resist the invasion of harmful substances in the external environment on the skin, enhance the skin's barrier function, and reduce external stimuli to the skin. On the other hand, the unique properties of silicone elastomers make the gel of the present application have a very good touch during the application process. After application, the skin surface is smoother and softer, and the user can feel a comfortable experience during use.

[0030] The present application disperses the microcapsules in the three-dimensional network structure of the silicone elastomer gel, so that the gel matrix can distribute the effective ingredients more evenly, thereby enhancing the stability of the product and the uniformity of efficacy release. This dispersion design improves the stability of the microcapsules in the matrix; at the same time, the wall material of the microcapsules and the silicone elastomer matrix have good compatibility, making the synergistic effect between the two more efficient and avoiding the problems of incompatibility and poor storage stability.

[0031] Preferably, the silicone elastomer gel includes the following components by mass: silicone elastomer: 15-30 parts; crosslinker: 0.5-5 parts; thickener: 0.1-2 parts; solvent: 60-80 parts; phase change component: 1-2 parts; moisturizing component: 5-8 parts; wall material: 6-30 parts. By adjusting the proportion of each component, the advantages of each component are fully utilized. The addition of crosslinker and thickener ensures the ideal texture and stability of the gel matrix; the amount of solvent used is controlled within an appropriate range, which helps to improve the solubility and dispersibility of the ingredients; the wall material is controlled at 6-30 parts, so that the present invention can play a good skin care effect under different skin types and climate conditions. Especially in hot or dry environments, moisturizing and comfort are significantly improved.

[0032] The present invention also provides a method for preparing a silicone elastomer gel for skin care products, comprising the following steps:

[0033] S100, adding an organosilicon elastomer, a crosslinking agent, and a thickener into a solvent, and stirring the mixture to obtain a gel matrix;

[0034] S200, dispersing the moisturizing component in deionized water and performing a heating treatment to obtain a core material; after uniformly mixing the phase change component with the wall material, coating the surface of the core material by a spray drying method to obtain a microcapsule;

[0035] S300, adding the microcapsules into the gel matrix, and mixing them evenly to obtain the silicone elastomer gel.

[0036] Furthermore, the organosilicon elastomer is a composite of modified titanium dioxide and siloxane chains, and its preparation includes the following steps:

[0037] S101. Under a nitrogen atmosphere, titanium dioxide powder is added to ethanol, and after mixing evenly, a dimethoxy quaternary ammonium salt siloxane monomer is added, and an organic silicone elastomer is obtained by ultrasonic treatment.

[0038] Preferably, titanium dioxide is dispersed in ethanol to ensure uniform dispersion, and then dimethoxy quaternary ammonium salt siloxane monomer is added to introduce quaternary ammonium salt groups into the surface of titanium dioxide to enhance its lipophilicity; the modified titanium dioxide has better compatibility with the silicone elastomer, preventing particle agglomeration and precipitation, forming a stable dispersion system, and effectively improving the ultraviolet absorption performance.

[0039] Furthermore, S100 specifically includes: S111, adding a silicone elastomer to a solvent, heating to 70-90°C for a first stirring treatment to obtain a first solution; S112, adding a crosslinking agent to the first solvent, performing a crosslinking reaction at 80-120°C for 30-60 minutes to obtain a second solution; S113, adding a thickener to the second solution, performing a second stirring treatment to obtain a gel matrix.

[0040] Preferably, the first stirring treatment is performed by adding the silicone elastomer to the solvent and heating it to 70-90°C to ensure that the silicone elastomer is fully dissolved and evenly dispersed in the solvent to form a stable first solution; the solvent is selected to include at least one of deionized water, ethanol, and propylene glycol, and these solvents can effectively dissolve the silicone elastomer; on this basis, a cross-linking agent is added for a cross-linking reaction, and the cross-linking agent includes 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, phenyltriethoxysilane, and phenyltrimethoxysilane, so that the gel matrix is ​​more stable and its elasticity and viscosity are enhanced. The temperature of the cross-linking reaction is controlled at 80-120°C and the time is controlled within 30-60 minutes to ensure that the cross-linking degree is moderate, and the gel is avoided from being too hard or unable to achieve the ideal texture due to excessive cross-linking; finally, a thickener is added for stirring treatment, and the thickener includes polyvinyl alcohol and sodium carboxymethyl cellulose, which can effectively improve the viscosity and rheology of the gel, so that the final gel matrix has better spreadability and stability during use, while avoiding component precipitation or stratification.

[0041] The present application adopts a two-step stirring treatment method, which helps to control the reaction conditions through step-by-step operation, avoids excessive reaction of the cross-linking agent or uneven dispersion of the silicone elastomer, thereby improving the quality and performance of the gel. The speed range of the first stirring treatment is 300-500rpm, and the time is 15-30 minutes, which helps to completely dissolve and evenly disperse the silicone elastomer, ensuring that a uniform first solution is obtained; the speed range of the second stirring treatment is 200-400rpm, and the time is 15-30 minutes, which helps to evenly disperse the thickener, avoid agglomeration of the thickener particles, and ensure the ideal viscosity and rheology of the final gel.

[0042] Specifically, S200 specifically includes: S210, adding a surfactant to the moisturizing component, dispersing it in deionized water with a temperature between 50-80°C, adding an adhesive, and heating it at 60-80°C for 30-60min to obtain a core material; S220, adding chitosan to deionized water, adding citric acid dropwise at 60-80°C, and stirring it until it is completely dissolved, adding a phase change component after dissolution, and mixing evenly to obtain a wall material; S230, adding the wall material dropwise into the core material and stirring it simultaneously, after the addition is completed, homogenizing the core material and the wall material under ultrasonic conditions of 40-60kHz for 10-30min to obtain a mixed solution; S240, sending the mixed solution to a spray dryer, the inlet temperature of the spray dryer is between 100-160°C, and the outlet temperature is between 50-80°C, and microcapsule particles are obtained by spray drying; S250, washing the microcapsule particles and centrifuging them to obtain microcapsules.

[0043] Preferably, the moisturizing component includes at least one of hyaluronic acid and glycerol, which mainly provides the active ingredient in the microcapsule and provides water and action; the surfactant includes at least one of Tween 20, Tween 80, and cocamidopropyl betaine, which helps to evenly disperse the moisturizing component in the aqueous phase to prevent it from aggregating or precipitating; the moisturizing component and the surfactant are mixed and dispersed in deionized water controlled at a temperature of 50-80°C, ensuring the uniform distribution of the active ingredient; adding an adhesive and heating it at 60-80°C makes the stability and structure of the core material more solid, ensuring the stability of the moisturizing component in the microcapsule and avoiding the loss or degradation of the component, and the adhesive includes at least one of gelatin and polyvinyl alcohol; by adding chitosan to an appropriate amount of deionized water Acid is added to water and heated to dissolve, and the obtained wall material can effectively wrap the components in the core material, provide physical protection and sustained-release effect; the core material and the wall material are homogenized under 40-60kHz ultrasonic conditions, which can improve the dispersion and uniformity, and help to achieve a good fusion of the core components and the wall material of the microcapsule; the spray drying method realizes the rapid drying of the effective ingredients and the precise control of the particles by controlling the inlet and outlet temperatures of the spray dryer, maintains the active ingredients of the microcapsules, and makes the microcapsule particles have a uniform particle size and good fluidity; the washing and centrifugal separation treatment in S205 removes the substances not involved in the encapsulation, ensures the purity and quality of the microcapsule particles, and ensures the consistency and stability of the microcapsule particles in the final product.

[0044] Furthermore, in S210, the phase change is separated into a modified acrylic ester copolymer, and the preparation method of the modified acrylic ester copolymer includes the following steps: S211, methyl acrylate, acrylic vinyl ether, ethyl acrylate, and polyvinyl alcohol are mixed and dissolved in ethanol, a plasticizer and an initiator are added, a polymerization reaction is carried out, and a modified acrylic ester copolymer is obtained after cooling.

[0045] Preferably, through the polymerization reaction, the molecular chain structure of the acrylic copolymer finally obtained has certain flexibility and hydrophobicity, so that the molecular chain of the material can relax or cross-link at around 37°, thereby causing the phase change of the material; in addition, the modified acrylic copolymer has good solubility and dispersibility, and is well compatible with other ingredients such as moisturizing ingredients and wall materials, ensuring the uniformity and stability of the microcapsules.

[0046] Further, S300, the microcapsules are added to the gel matrix, and the mixture is evenly mixed to obtain the silicone elastomer gel; the temperature during the mixing process is controlled between 20-40°C to avoid high temperature from damaging the active ingredients in the microcapsules. Excessive temperature may cause the ingredients to degrade or volatilize, while low temperature helps to maintain the stability of these ingredients and ensure the activity and effect of the microcapsules; the mixing time is set to 30-60 minutes to ensure that the ingredients can be fully mixed and reacted, further improving the quality and consistency of the microcapsules and avoiding the particles being too loose or uneven.

[0047] Furthermore, S400, the silicone elastomer gel is subjected to temperature control treatment, degassing treatment, and additives are added in sequence to obtain the final product. The purpose of temperature control treatment is to ensure that the silicone elastomer gel is stabilized under suitable temperature conditions to ensure the uniformity and quality consistency of the final product; degassing treatment can effectively remove bubbles in the gel to avoid the impact of bubbles on the final product, ensure the smooth surface of the silicone elastomer gel, and avoid bubbles causing product stratification or property changes during long-term storage; the purpose of adding additives is to further improve the performance of the gel and enhance its moisturizing, repairing and other skin care effects. Additives include antioxidants, preservatives, fragrances, etc. Additives can improve product performance, extend shelf life, and make the final product more competitive in the market.

[0048] Example 1

[0049] This embodiment provides a method for preparing an organic silicone elastomer gel for skin care products. The organic silicone elastomer gel comprises: 20 parts of organic silicone elastomer; 1 part of cross-linking agent; 1 part of thickener; 70 parts of solvent; 1 part of phase change component; 7 parts of moisturizing component; and 11 parts of wall material. The specific preparation method is as follows:

[0050] S101, under a nitrogen atmosphere, adding titanium dioxide powder to ethanol, mixing evenly, adding dimethoxy quaternary ammonium salt siloxane monomer, and performing ultrasonic treatment to obtain an organosilicon elastomer;

[0051] S111, adding an organosilicon elastomer to deionized water, heating to 80° C. at a rotation speed of 400 rpm for 20 min, and performing a first stirring treatment to obtain a first solution;

[0052] S112, adding 3-aminopropyltriethoxysilane to the first solvent, and performing a cross-linking reaction at a temperature of 100° C. for 45 minutes to obtain a second solution;

[0053] S113, adding polyvinyl alcohol to the second solution, and performing a second stirring treatment at a rotation speed of 300 rpm for 20 min to obtain a gel matrix;

[0054] S210, adding Tween 20 to hyaluronic acid, dispersing the mixture in deionized water at 60° C., adding gelatin, and heating the mixture at 70° C. for 45 minutes to obtain a core material;

[0055] S211, mixing methyl acrylate, acrylic acid vinyl ether, ethyl acrylate, and polyvinyl alcohol and dissolving them in ethanol, adding a plasticizer and an initiator, performing a polymerization reaction, and obtaining a phase change component after cooling;

[0056] S220, adding chitosan to deionized water, adding citric acid dropwise at 70° C., and stirring until the chitosan is completely dissolved, and after the chitosan is dissolved, adding the phase change component, and mixing evenly to obtain the wall material;

[0057] S230, adding the wall material dropwise into the core material and stirring simultaneously, and after the dropwise addition is completed, homogenizing the core material and the wall material under 50 kHz ultrasonic conditions for 20 minutes to obtain a mixed solution;

[0058] S240, sending the mixed solution into a spray dryer, wherein the inlet temperature of the spray dryer is 140° C. and the outlet temperature is 60° C., and microcapsule particles are obtained by spray drying;

[0059] S250, washing the microcapsule particles and then centrifuging to obtain microcapsules;

[0060] S300, adding the microcapsules into the gel matrix, mixing evenly at a temperature of 30° C. for 45 min to obtain an organosilicon elastomer gel.

[0061] Example 2

[0062] This embodiment provides a method for preparing an organic silicone elastomer gel for skin care products. The organic silicone elastomer gel comprises: an organic silicone elastomer: 15 parts; a cross-linking agent: 0.5 parts; a thickener: 0.1 parts; a solvent: 60 parts; a phase change component: 1 part; a moisturizing component: 5 parts; and a wall material: 6 parts. The specific preparation method is as follows:

[0063] S111, adding dimethyl silicone oil to deionized water, heating to 70° C. at a rotation speed of 500 rpm for 15 min, and performing a first stirring treatment to obtain a first solution;

[0064] S112, adding 3-aminopropyltrimethoxysilane to the first solvent, and performing a cross-linking reaction at a temperature of 80° C. for 60 minutes to obtain a second solution;

[0065] S113, adding sodium carboxymethyl cellulose to the second solution, and performing a second stirring treatment at a rotation speed of 200 rpm for 30 min to obtain a gel matrix;

[0066] S210, adding Tween 80 to glycerol, dispersing the mixture in deionized water at a temperature of 50° C., adding polyvinyl alcohol, and heating the mixture at 70° C. for 45 minutes to obtain a core material;

[0067] S211, mixing methyl acrylate, acrylic acid vinyl ether, ethyl acrylate, and polyvinyl alcohol and dissolving them in ethanol, adding a plasticizer and an initiator, performing a polymerization reaction, and obtaining a phase change component after cooling;

[0068] S220, adding chitosan to deionized water, adding citric acid dropwise at 60° C., and stirring until the chitosan is completely dissolved, and after the chitosan is dissolved, adding the phase change component, and mixing evenly to obtain the wall material;

[0069] S230, adding the wall material dropwise into the core material and stirring simultaneously, and after the dropwise addition is completed, homogenizing the core material and the wall material under 40 kHz ultrasonic conditions for 30 minutes to obtain a mixed solution;

[0070] S240, sending the mixed solution into a spray dryer, wherein the inlet temperature of the spray dryer is 100° C. and the outlet temperature is 50° C., and microcapsule particles are obtained by spray drying;

[0071] S250, washing the microcapsule particles and then centrifuging to obtain microcapsules;

[0072] S300, adding the microcapsules into the gel matrix, and mixing them uniformly at a temperature of 20° C. for 60 min to obtain an organosilicon elastomer gel;

[0073] S400, subjecting the silicone elastomer gel to temperature control treatment and degassing treatment in sequence, and adding a sunscreen agent to obtain a final product.

[0074] Example 3

[0075] This embodiment provides a method for preparing an organic silicone elastomer gel for skin care products. The organic silicone elastomer gel comprises: an organic silicone elastomer: 30 parts; a cross-linking agent: 5 parts; a thickener: 2 parts; a solvent: 80 parts; a phase change component: 2 parts; a moisturizing component: 8 parts; and a wall material: 30 parts. The specific preparation method is as follows:

[0076] S101, under a nitrogen atmosphere, adding titanium dioxide powder to ethanol, mixing evenly, adding dimethoxy quaternary ammonium salt siloxane monomer, and performing ultrasonic treatment to obtain an organosilicon elastomer;

[0077] S111, adding silicone elastomer to propylene glycol, heating to 70° C. at a rotation speed of 300 rpm for 30 min, and performing a first stirring treatment to obtain a first solution;

[0078] S112, adding phenyltriethoxysilane to the first solvent, and performing a cross-linking reaction at a temperature of 120° C. for 30 minutes to obtain a second solution;

[0079] S113, adding sodium carboxymethyl cellulose to the second solution, and performing a second stirring treatment at a rotation speed of 400 rpm for 15 min to obtain a gel matrix;

[0080] S210, adding cocamidopropyl betaine to glycerol, dispersing the mixture in deionized water at a temperature of 50° C., adding polyvinyl alcohol, and heating the mixture at 70° C. for 45 minutes to obtain a core material;

[0081] S211, mixing methyl acrylate, acrylic acid vinyl ether, ethyl acrylate, and polyvinyl alcohol and dissolving them in ethanol, adding a plasticizer and an initiator, performing a polymerization reaction, and obtaining a phase change component after cooling;

[0082] S220, adding chitosan to deionized water, adding citric acid dropwise at 80° C., and stirring until the chitosan is completely dissolved, and after the chitosan is dissolved, adding the phase change component, and mixing evenly to obtain the wall material;

[0083] S230, adding the wall material dropwise into the core material and stirring simultaneously, after the dropping is completed, homogenizing the core material and the wall material under 40kHz ultrasonic conditions for 30 minutes to obtain a mixed solution; S204, sending the mixed solution into a spray dryer, the inlet temperature of the spray dryer is 160°C, and the outlet temperature is 80°C, and microcapsule particles are obtained by spray drying;

[0084] S205, washing the microcapsule particles and then centrifuging to obtain microcapsules;

[0085] S300, adding the microcapsules into the gel matrix, and mixing them uniformly at a temperature of 40° C. for 30 min to obtain an organosilicon elastomer gel;

[0086] S400, subjecting the silicone elastomer gel to temperature control treatment and degassing treatment in sequence, and adding a preservative to obtain a final product.

[0087] Performance Testing

[0088] Water release and moisturizing effect test: The moisture release rate of the gel of Examples 1-3 was measured using a moisture transmission rate (MVTR) tester to ensure that it has a moisturizing effect for a long time. The structure is shown in Table 1;

[0089] Temperature control effect test: The temperature control effect of the phase change material is tested by a skin temperature change monitor to ensure that it can provide a comfortable temperature experience when in contact with the skin. The results are shown in Table 1.

[0090] Stability test: The samples of Examples 1-3 were exposed to an environment of 40° C. and 75% relative humidity for 6 months, and the stability of the appearance, viscosity, color, and pH value of the products were monitored. The results are shown in Table 1;

[0091] UV test: The samples of Examples 1-3 were coated on a transparent substrate, and the absorption of ultraviolet rays of different wavelengths in the wavelength range of 280-320 nm was measured using a UV-visible spectrophotometer. The results are shown in Table 1.

[0092] Table 1

[0093]

[0094] (1) Since the microcapsules in the present invention have a long-lasting sustained release function, the moisturizing components are slowly released through the wall material of the microcapsules. The low water permeability shown in Table 1 indicates that the gel has a long lasting moisturizing effect;

[0095] (2) As can be seen from Table 1, the temperature change range maintains the skin temperature in a relatively constant range, avoiding overheating or overcooling, and providing a comfortable feeling to the skin. This is because the phase change component can undergo phase change within a specific temperature range, thereby effectively regulating the skin temperature and achieving a comfortable use effect;

[0096] (3) As can be seen from Table 1, due to the presence of the silicone elastomer gel and microcapsules, Examples 1-3 can exhibit good stability under normal conditions, and contain antioxidants and preservatives. Therefore, they can exhibit good stability in the stability test, and the product appearance, texture and active ingredients will not change significantly after being stored for a period of time;

[0097] (4) Since modified titanium dioxide is used in Examples 1 and 3, the absorbance is relatively high, which proves that the ultraviolet absorption performance is strong; on the contrary, Example 2 is relatively weak, with a lower absorbance, indicating that its ultraviolet absorption performance is weak.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A silicone elastomer gel for skin care products, characterized in that: The silicone elastomer gel comprises: A gel matrix comprising a silicone elastomer, a cross-linking agent, a thickener and a solvent; Microcapsules, wherein the microcapsules are dispersed in the three-dimensional network structure of the gel matrix, and the microcapsules include a core material and a wall material; The wall material wraps the core material, the core material includes a moisturizing component, and the wall material includes a phase-changing component.

2. The silicone elastomer gel according to claim 1, characterized in that: The phase transformation is to form a modified acrylic ester copolymer, and the number average molecular weight of the modified acrylic ester copolymer is between 10000-50000 g / mol.

3. The silicone elastomer gel according to claim 1, characterized in that: The silicone elastomer gel comprises the following components in parts by mass: Silicone elastomer: 15-30 parts; Cross-linking agent: 0.5-5 parts; Thickener: 0.1-2 parts; Solvent: 60-80 parts; Phase change component: 1-2 parts; Moisturizing component: 5-8 parts; Wall material: 6-30 parts.

4. A method for preparing a silicone elastomer gel for skin care products, characterized in that: The preparation method is used to prepare the silicone elastomer gel according to any one of claims 1 to 3, and the preparation method comprises the following steps: S100, adding the silicone elastomer, the crosslinking agent, and the thickener into the solvent, and stirring to obtain a gel matrix; S200, dispersing the moisturizing component in deionized water and performing a heating treatment to obtain the core material; after uniformly mixing the phase change component with the wall material, coating the surface of the core material by a spray drying method to obtain the microcapsule; S300, adding the microcapsules into the gel matrix, and mixing them evenly to obtain the organosilicon elastomer gel.

5. The preparation method according to claim 4, characterized in that: The S100 specifically includes: S111, adding the organosilicon elastomer to the solvent, heating to 70-90° C. and performing a first stirring treatment to obtain a first solution; S112, adding the cross-linking agent to the first solvent, and performing a cross-linking reaction at 80-120° C. for 30-60 minutes to obtain a second solution; S113, adding the thickener to the second solution, performing a second stirring process, and obtaining the gel matrix.

6. The preparation method according to claim 5, characterized in that: In S111, the solvent includes at least one of deionized water, ethanol, and propylene glycol; and / or In the S111, the rotation speed of the first stirring process is in the range of 300-500 rpm and the time is in the range of 15-30 min; and / or In the S111, the second stirring process is performed at a speed ranging from 200 to 400 rpm and for a time ranging from 15 to 30 minutes; and / or In S112, the crosslinking agent includes at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, phenyltriethoxysilane, and phenyltrimethoxysilane; and / or In S113, the thickener includes at least one of polyvinyl alcohol and sodium carboxymethyl cellulose.

7. The preparation method according to claim 4, characterized in that: The S200 specifically includes: S210, adding a surfactant to the moisturizing component, dispersing the mixture in deionized water at a temperature of 50-80° C., adding a binder, and performing a heating treatment at 60-80° C. for 30-60 min to obtain the core material; S220, adding chitosan to deionized water, adding citric acid dropwise at 60-80° C., stirring until completely dissolved, adding the phase change component after dissolution, and mixing uniformly to obtain the wall material; S230, dropping the wall material into the core material and stirring simultaneously, after the dropping is completed, homogenizing the core material and the wall material under ultrasonic conditions of 40-60 kHz for 10-30 minutes to obtain a mixed solution; S240, sending the mixed solution into a spray dryer, wherein the inlet temperature of the spray dryer is between 100-160° C., and the outlet temperature is between 50-80° C., and microcapsule particles are obtained by the spray drying method; S250, washing the microcapsule particles and then centrifuging them to obtain the microcapsules.

8. The preparation method according to claim 7, characterized in that: In the S210, the moisturizing component includes at least one of hyaluronic acid and glycerin; and / or In the S210, the adhesive includes at least one of gelatin and polyvinyl alcohol; In S250, the centrifugal treatment time is between 30-60 minutes.

9. The preparation method according to any one of claims 4 to 8, characterized in that: In the S210, the phase transformation is separated into a modified acrylic ester copolymer, and the preparation method of the modified acrylic ester copolymer comprises the following steps: S211, mixing methyl acrylate, acrylic acid vinyl ether, ethyl acrylate and polyvinyl alcohol and dissolving them in ethanol, adding a plasticizer and an initiator, carrying out a polymerization reaction, and obtaining the phase change component after cooling.

10. The preparation method according to any one of claims 4 to 8, characterized in that: In the S300, the temperature during the mixing process is controlled between 20-40°C, and the time is controlled between 30-60 minutes.

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