High-efficiency long-acting mosquito-repelling moisturizing soothing emulsion and preparation method thereof

Abstract

The invention provides an efficient long-acting mosquito-repelling moisturizing soothing emulsion and a preparation method thereof. The efficient long-acting mosquito-repelling moisturizing soothing emulsion comprises 6.0-10.0% of butyl acetamido ethyl propionate serving as a mosquito-repelling active substance, and the balance of water. The pH buffer system is composed of sodium citrate and citric acid and is used for stabilizing the pH value of the product in an optimal range of 6.0 to 6.5 so as to prevent hydrolysis of active matters; the synergistic soothing protection system comprises at least two of bisabolol, a radix sophorae flavescentis extract and allantoin and is used for neutralizing potential skin irritation. On the premise of conforming to cosmetic laws and regulations, the repellent rate of not less than 90% and the effective protection time of more than 6 hours are realized, meanwhile, tests show that the stimulation rate to sensitive skin is 0%, and the composition has excellent chemical stability and skin care feeling.

Description

Technical Field

[0001] This invention relates to the field of mosquito repellent lotion technology, and in particular to a highly effective and long-lasting mosquito repellent, moisturizing, and soothing lotion and its preparation method. Background Technology

[0002] Currently, the market for topical insect repellents used on human skin to prevent mosquito bites has seen significant technological differentiation. This differentiation mainly stems from the differences in regulatory standards, technological approaches, and core requirements followed by different product categories, leading to a long-standing unresolved core contradiction in existing technologies: the difficulty in achieving a balance between cosmetic-grade safety and pesticide-grade efficacy.

[0003] Existing technologies can be mainly divided into two categories:

[0004] The first category consists of cosmetic-grade (makeup-approved) mosquito repellent products that comply with the "Cosmetic Safety Technical Specifications." These products prioritize safety and gentleness, and their regulatory framework imposes strict restrictions on the selection and dosage of their active ingredients. For example, ethyl butylacetylaminopropionate (commonly known in the industry as IR3535) is one of the few mosquito repellents approved for use in cosmetics, but its maximum permissible addition is usually no more than 10%. To ensure extreme gentleness, commercially available products generally control the concentration of this ingredient at even lower levels (e.g., below 5%). This directly leads to limitations in its mosquito-repellent efficacy, typically manifesting as a low repellency rate (e.g., less than 70% repellency against common Culex pipiens pallens) and a short duration of protection (usually 2 to 3 hours).

[0005] The second category consists of disinfectant-grade (disinfectant approval number) or pesticide-grade (pharmaceutical approval number) mosquito repellent products. These products prioritize maximum mosquito-repelling effectiveness and often use high concentrations of potent mosquito repellents, such as DEET (concentrations can reach 10%-30%) or picaridin. While these products demonstrate excellent mosquito-repelling efficacy, their formulations are not designed according to cosmetic safety standards, leading to a higher risk of skin irritation. Clinical data shows that the incidence of irritation in people with sensitive skin can be as high as 40% or more, and they are generally not suitable for special groups such as infants and pregnant women. Therefore, they cannot meet the skincare-grade safety requirements for daily, long-term, and full-body use.

[0006] Regarding the active ingredient, ethyl butyl acetylaminopropionate (IR3535), while widely recognized as a safe and effective cosmetic mosquito repellent, presents challenges in terms of chemical stability. As an ester compound, IR3535 is prone to hydrolysis under acidic or alkaline conditions, leading to degradation and inactivation. This significantly limits the duration of its effective concentration on the skin surface. While existing cosmetic formulations acknowledge this, they typically only perform routine pH adjustments and fail to establish a buffer system that precisely and persistently maintains the pH within the optimal stability range. This results in premature degradation of the active ingredient during storage and use, failing to achieve long-lasting protection. Summary of the Invention

[0007] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an effective and long-lasting mosquito repellent, moisturizing and soothing lotion and its preparation method, so as to solve the problem that mosquito repellent products in the prior art cannot meet the skin care safety requirements for daily, long-term, and whole-body use.

[0008] To achieve the above and other related objectives, the present invention provides a highly effective and long-lasting mosquito-repellent, moisturizing, and soothing lotion, comprising, by weight percentage of the total composition: a mosquito-repellent system comprising 6.0% to 10.0% ethyl butylacetaminopropionate as the active mosquito-repellent ingredient; a formulation stabilizing system comprising sodium citrate and citric acid, wherein the amount of the buffer system is sufficient to maintain the final pH value of the composition within the range of 6.0 to 6.5; a soothing and protective system comprising at least two components selected from the group consisting of bisabolol, sophora flavescens root extract, and allantoin; and a solvent comprising purified water.

[0009] By adopting the above technical solutions, and through the synergistic effect of high-concentration compliant mosquito repellent, formulation stabilization system, and soothing system, the technical challenge of balancing safety and efficacy has been solved while complying with cosmetic regulations, achieving a balance between powerful and long-lasting mosquito repellency and extreme gentleness and safety.

[0010] In one embodiment of the present invention, a moisturizing system is further included, the moisturizing system comprising glycerin, sodium hyaluronate and panthenol.

[0011] By adopting the above technical solutions, a three-dimensional moisturizing network of "hydration-moisturization-repair" is constructed, enabling the product to have excellent daily skincare functions, thereby enhancing the product's versatility and user experience.

[0012] In one embodiment of the present invention, the dosage form stabilization system further includes an emulsification system, wherein the emulsification system includes C12-16 alcohol and arachidonic acid glucoside.

[0013] By adopting the above technical solution, while ensuring the physical stability of the emulsion, the emulsification system provides excellent gentleness and low irritation, which is highly consistent with the product's safety requirements for sensitive skin.

[0014] In one embodiment of the present invention, the composition is an oil-in-water emulsion with an average particle size of less than or equal to 3 μm.

[0015] By adopting the above technical solutions, the product can be given a superior skin feel that is light, easily absorbed, and non-sticky, and the physical stability of the emulsion can be enhanced to prevent oil-water separation.

[0016] In one embodiment of the present invention, the solvent further includes butanediol and p-hydroxyacetophenone.

[0017] By adopting the above technical solution, butanediol is used as an auxiliary solvent, which also has a slight anti-corrosion effect, reducing the amount of synthetic preservatives used. Then, p-hydroxyacetophenone is used to produce a fractional oxidant, which replaces traditional synthetic preservatives (such as phenoxyethanol) and reduces irritation.

[0018] A method for preparing a highly effective and long-lasting mosquito repellent, moisturizing and soothing lotion as described above includes the following steps: S1, aqueous phase preparation, preparing an aqueous phase including water-soluble components and a formulation stabilization system, and heating the aqueous phase to a first temperature of 72°C to 75°C;

[0019] S2. Oil phase preparation: Prepare an oil phase comprising ethyl butyl acetylaminopropionate and an oil-soluble component, and heat the oil phase to a second temperature substantially the same as the first temperature; S3. Vacuum homogenization and emulsification: Combine the oil phase and the aqueous phase in an emulsification vessel under a vacuum of -0.08 to -0.09 MPa, and homogenize at a high shear rate of 2200 to 3000 rpm to form a primary emulsion; S4. Cooling and addition of soothing ingredients: Cool the primary emulsion to a temperature of 40°C to 42°C; and add a heat-sensitive soothing system to the cooled primary emulsion, mixing to form a final composition, wherein the pH value of the final composition is maintained in the range of 6.0 to 6.5; S5. Filtration: Filter the generated final composition to complete the preparation.

[0020] By adopting the above technical solution and precisely controlling the temperature, vacuum degree and homogenization speed, the uniformity of emulsion particle size and the stability of physical properties are ensured, and the bioactivity of heat-sensitive active ingredients is preserved to the maximum extent, providing process assurance for the efficacy stability and safety of the product.

[0021] In one embodiment of the present invention, in step S1, glycerol and sodium hyaluronate are premixed to prepare a premixed solution, which is then added to an emulsifying pot along with purified water, panthenol, p-hydroxyacetophenone, butanediol, sodium citrate, and citric acid. The mixture is heated to 72-75°C and stirred at 600-800 rpm for 12-15 minutes until it becomes completely transparent.

[0022] By adopting the above technical solution, high temperature ensures complete dissolution of p-hydroxyacetophenone, thus exerting its antioxidant effect; precise temperature avoids deterioration of the aqueous phase components.

[0023] In one embodiment of the present invention, in step S2, C12-16 alcohol, ethylhexanoate, and ethyl butylacetylaminopropionate are added to the oil phase pot, heated to the same temperature as the aqueous phase, and stirred at 500-600 rpm for 8-10 minutes until completely melted.

[0024] By adopting the above technical solution, the temperature fluctuations during emulsification are avoided, which may lead to particle formation; the mosquito repellent ingredients are ensured to dissolve completely, and uneven dispersion is avoided, which may affect the efficacy.

[0025] In one embodiment of the present invention, in step S4, the mixture is cooled to 40-42°C, and bisabolol, sophora flavescens extract, and allantoin are added. The mixture is stirred at 1000-1200 rpm for 5 minutes until homogeneous.

[0026] By adopting the above technical solutions, the activity of soothing ingredients (such as bisabolol) is avoided; precise stirring ensures that the soothing ingredients are evenly dispersed, thus exerting a full-face protective effect.

[0027] As described above, the long-lasting mosquito-repellent, moisturizing, and soothing lotion of the present invention and its preparation method have the following beneficial effects:

[0028] 1. Achieves strong and long-lasting mosquito repellent effect under cosmetic regulations and standards: This invention uses a high concentration of compliant mosquito repellent of 6.0% to 10.0% and combines it with a pH buffer system to ensure its stability, achieving a repellency rate of no less than 90% against major mosquito species (such as Culex pipiens pallens) and an effective protection time of no less than 6 hours.

[0029] 2. Achieves ultimate safety and skin compatibility: This invention introduces a multi-component synergistic soothing system composed of bisabolol, sophora flavescens root extract, and allantoin, which effectively neutralizes the slight skin irritation that may be caused by high concentrations of active ingredients.

[0030] 3. Significantly improves the chemical and physical stability of the product: One of the core technologies of this invention is the use of sodium citrate-citric acid buffer pair, which precisely and persistently stabilizes the product's pH value within the optimized range of 6.0-6.5, where the hydrolysis rate of ethyl p-butylacetaminopropionate is lowest.

[0031] 4. Provides an excellent skin feel and daily skincare experience: By adopting a vacuum high-shear homogenization process, the emulsion prepared by this invention has uniform and small particle size, light texture, is easy to apply, absorbs quickly, and has no stickiness.

[0032] 5. Precise and controllable process parameters, with advantages for industrialization: In the preparation method provided by this invention, the key parameters such as temperature, rotation speed, time, and vacuum degree of each step have clear control ranges, which makes it easy to achieve large-scale production on existing cosmetic production lines. The efficacy deviation between batches can be controlled within 5%, and the product qualification rate is high, laying a solid foundation for the commercial application of the technological achievement. Detailed Implementation

[0033] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0034] It should be understood that any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the present invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity of description and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0035] Example 1:

[0036] This invention provides a highly effective, long-lasting mosquito-repellent, moisturizing, and soothing lotion, comprising, by weight percentage of the total composition:

[0037] The mosquito repellent system includes ethyl butyl acetylaminopropionate at a concentration of 6.0-10.0% as the active mosquito repellent ingredient;

[0038] The dosage form stabilization system comprises 0.03-0.1% sodium citrate and 0.02-0.08% citric acid, wherein the amount of buffer system is sufficient to maintain the final pH of the composition in the range of 6.0 to 6.5;

[0039] The soothing and protective system includes 0.2-0.5% bisabolol, 0.8-3.0% Sophora flavescens root extract and 0.1-0.3% allantoin;

[0040] The moisturizing system comprises 4.0-7.0% glycerin, 0.02-0.1% sodium hyaluronate, and 1.0-3.0% panthenol.

[0041] The solvents include 65-80% purified water, 2.0-5.0% butanediol, and 0.3-0.8% p-hydroxyacetophenone.

[0042] The composition is an oil-in-water emulsion with an average particle size of less than or equal to 3 μm.

[0043] The formulation stabilization system also includes 0.3-1.0% C12-16 alcohol and 0.2-0.8% arachidonic acid glucoside.

[0044] It also includes 2.0-5.0% ethylhexanoate as an oil-soluble emollient.

[0045] Example 2:

[0046] This embodiment provides a specific formula for a highly effective, long-lasting mosquito-repellent, moisturizing, and soothing lotion as described in Embodiment 1. The weight percentages of each component are shown below:

[0047] The mosquito repellent system includes ethyl butyl acetylaminopropionate at a concentration of 8.0%.

[0048] The formulation stabilization system includes 0.07% sodium citrate, 0.05% citric acid, 0.8% C12-16 alcohol, and 0.5% arachidonic acid glucoside.

[0049] The soothing and protective system includes 0.3% bisabolol, 1.5% Sophora flavescens root extract and 0.2% allantoin.

[0050] The moisturizing system comprises 5.0% glycerin, 0.05% sodium hyaluronate, and 2.0% panthenol.

[0051] The solvents consist of 72.95% purified water, 3.0% butanediol, and 0.5% p-hydroxyacetophenone.

[0052] This embodiment also includes 3.0% ethylhexanoate.

[0053] Example 3:

[0054] This embodiment provides a method for preparing a highly effective, long-lasting mosquito-repellent, moisturizing, and soothing lotion as described in Embodiment 1 or 2, comprising the following steps:

[0055] S1. Aqueous phase preparation: preparing an aqueous phase comprising water-soluble components and a dosage form stabilization system, and heating the aqueous phase to a first temperature of 72°C to 75°C;

[0056] S2. Oil phase preparation: preparing an oil phase comprising ethyl butylacetylaminopropionate and an oil-soluble component, and heating the oil phase to a second temperature substantially the same as the first temperature;

[0057] S3. Vacuum homogenization emulsification: Under vacuum conditions of -0.08 to -0.09 MPa, the oil phase and water phase are combined in an emulsification vessel and homogenized at a speed of 2200 to 3000 rpm to form a primary emulsion.

[0058] S4. Cooling and soothing ingredients are added to cool the primary emulsion to a temperature of 40°C to 42°C; and a heat-sensitive soothing system is added to the cooled primary emulsion to form a final composition, wherein the pH value of the final composition is maintained in the range of 6.0 to 6.5.

[0059] S5. Filtration: Filter the resulting final composition to complete the preparation.

[0060] In step S1, all raw materials are verified for compliance before preparation. After passing the test, glycerol and sodium hyaluronate are premixed to prepare a premixed solution. Then, the premixed solution is added to an emulsifying pot along with purified water, panthenol, p-hydroxyacetophenone, butanediol, sodium citrate, and citric acid. The pot is heated to 72-75℃ and stirred at 600-800 rpm for 12-15 minutes until completely transparent. After the premixed solution is prepared, all raw materials are tested for compliance.

[0061] In step S2, C12-16 alcohol, ethylhexanoate, and ethyl butylacetylaminopropionate are added to the oil phase pot, heated to the same temperature as the aqueous phase, and stirred at 500-600 rpm for 8-10 minutes until completely melted.

[0062] In step S3, the oil phase is drawn into the emulsification tank at a speed of 10-12 L / min and homogenized at a speed of 2200 to 3000 rpm for 5 min. After the oil phase is drawn out, the speed is increased to 2800-3000 rpm and homogenization is continued for 3-5 min.

[0063] In step S4, cool to 40-42℃, add bisabolol, sophora flavescens extract and allantoin, and stir at 1000-1200 rpm for 3-5 minutes until homogeneous.

[0064] Before step S5, the composition prepared in step S4 is subjected to pH and efficacy verification. The pH of the emulsion is tested (it should be between 6.0 and 6.5). If there is a deviation, it is finely adjusted with 0.1% citric acid / sodium hydroxide solution. At the same time, the content of mosquito repellent ingredients is tested (it should be between 6.0 and 10.0%) to ensure that the pH is stable, the mosquito repellent ingredients are prevented from hydrolysis, and the mosquito repellent efficacy is guaranteed.

[0065] In step S5, the composition from step S4 is cooled to 30-32°C, and samples are taken for testing of microorganisms (total colony count ≤500 CFU / g, mold and yeast ≤100 CFU / g) and heavy metals (≤1 ppm). After passing the tests, the mixture is filtered through a 100-mesh filter cloth and transferred to a sterile finished product container to complete the preparation.

[0066] In summary, this invention, through systematic and innovative design of mosquito repellent concentration, pH stabilization system, compound soothing system, and preparation process, has successfully developed a multifunctional protective lotion within the framework of cosmetic regulations. This lotion combines highly effective and long-lasting mosquito repellency, extreme safety and gentleness, moisturizing and skin-care benefits, and a superior skin feel. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and possesses high industrial applicability.

[0067] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A highly effective, long-lasting mosquito-repellent, moisturizing, and soothing lotion, characterized in that, The composition comprises, by weight percentage, a mosquito repellent system comprising 6.0% to 10.0% ethyl butylacetylaminopropionate as an active mosquito repellent ingredient; A formulation stabilization system comprising sodium citrate and citric acid, wherein the amount of the buffer system is sufficient to maintain the final pH of the composition in the range of 6.0 to 6.5; The soothing and protective system includes bisabolol, sophora flavescens root extract, and allantoin; Solvents, including purified water.

2. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 1, characterized in that: It also includes a moisturizing system, which comprises glycerin, sodium hyaluronate, and panthenol.

3. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 1, characterized in that: The dosage form stabilization system also includes an emulsification system, which comprises C12-16 alcohol and arachidonic acid glucoside.

4. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 1, characterized in that: The composition is an oil-in-water emulsion with an average particle size of less than or equal to 3 μm.

5. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 1, characterized in that: The solvent also includes butanediol and p-hydroxyacetophenone.

6. A method for preparing a highly effective, long-lasting mosquito-repellent, moisturizing, and soothing lotion as described in any one of claims 1-5, characterized in that: Includes the following steps: S1. Aqueous phase preparation: preparing an aqueous phase comprising water-soluble components and a dosage form stabilization system, and heating the aqueous phase to a first temperature of 72°C to 75°C; S2. Oil phase preparation: preparing an oil phase comprising ethyl butylacetylaminopropionate and an oil-soluble component, and heating the oil phase to a second temperature substantially the same as the first temperature; S3. Vacuum homogenization emulsification: Under vacuum conditions of -0.08 to -0.09 MPa, the oil phase and water phase are combined in an emulsification vessel and homogenized at a speed of 2200 to 3000 rpm to form a primary emulsion. S4. Cooling and soothing ingredients are added to cool the primary emulsion to a temperature of 40°C to 42°C; and a heat-sensitive soothing system is added to the cooled primary emulsion to form a final composition, wherein the pH value of the final composition is maintained in the range of 6.0 to 6.

5. S5. Filtration: Filter the resulting final composition to complete the preparation.

7. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 6, characterized in that: In step S1, glycerol and sodium hyaluronate are premixed to prepare a premixed solution, which is then added to an emulsifying pot along with purified water, panthenol, p-hydroxyacetophenone, butylene glycol, sodium citrate, and citric acid. The mixture is heated to 72-75°C and stirred at 600-800 rpm for 12-15 minutes until it becomes completely transparent.

8. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 6, characterized in that: In step S2, C12-16 alcohol, ethylhexanoate, and ethyl butylacetylaminopropionate are added to the oil phase pot, heated to the same temperature as the aqueous phase, and stirred at 500-600 rpm for 8-10 minutes until completely melted.

9. The high-efficiency, long-lasting mosquito-repellent, moisturizing, and soothing lotion according to claim 6, characterized in that: In step S4, the mixture is cooled to 40-42°C, and bisabolol, sophora flavescens extract, and allantoin are added. The mixture is stirred at 1000-1200 rpm for 3-5 minutes until homogeneous.