A stable emulsified composition, its preparation method and application

Abstract

This invention provides a stable emulsified composition, its preparation method, and its application, relating to the field of cosmetic technology. The stable emulsified composition comprises water, an emulsifier, and an aqueous thickener. This invention utilizes a specific emulsifier and sclerotium gum to synergistically construct a high-strength water-oil interface film and a stable spatial rheological network, effectively resisting the damage to the system's physical structure caused by the harsh low pH environment resulting from high-concentration acidic components. This completely solves the problems of demulsification, layering, and viscosity failure, ensuring long-term stability. Simultaneously, this composition overcomes the skin-feel defects of traditional high-acid products, stably carrying highly active acidic components while providing the product with a refreshing, delicate, and moisturizing superior sensory experience.

Description

Technical Field

[0001] This invention relates to the field of cosmetic technology, and more specifically, to a stable emulsified composition, its preparation method, and its application. Background Technology

[0002] Alpha-hydroxy acids, such as glycolic acid, are widely used in cosmetics as highly effective active ingredients to promote skin cell turnover, improve skin texture, and combat aging. However, high concentrations of these acidic ingredients (such as 6% and above) pose a significant challenge to emulsification systems.

[0003] Specifically, the strong acidity (low pH value) and hydrophilic environment created by high concentrations of acidic substances can easily damage the interfacial film formed by emulsifiers, leading to phenomena such as demulsification, layering, viscosity decrease, or discoloration, severely affecting product stability and shelf life. At the same time, this harsh acidic environment also places extremely high demands on the stability of thickeners; many conventional thickeners will hydrolyze or lose their thickening ability in such environments.

[0004] Currently, acid-containing skincare products on the market often adopt a compromise formulation strategy: one is to maintain the stability of the system by reducing the acid concentration, but this will directly sacrifice the expected efficacy of the product; the other is to use non-emulsified systems (such as pure water-based serums, gels, etc.), but such non-emulsified formulations are often inferior to emulsified creams or lotions in terms of skin feel and moisturizing properties.

[0005] In summary, existing technologies lack an emulsified composition that can stably withstand high concentrations of acidic components while providing an excellent sensory experience (such as a refreshing, delicate, and soft feel). Therefore, developing an emulsified system that is resistant to high acids, highly stable, and has an excellent skin feel has become an urgent technical problem to be solved in this field.

[0006] In view of this, the present invention is hereby proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a stable emulsified composition, its preparation method and application. In the emulsified composition, a tough network synergistically constructed by a specific emulsifier and Sclerotium sclerotium gum completely overcomes the problems of demulsification and viscosity failure caused by a high concentration of acidic environment. While ensuring efficient keratin renewal activity, it provides a refreshing, delicate and moisturizing superior sensory experience.

[0008] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: In a first aspect, the present invention provides a stable emulsifying composition comprising water, an emulsifier, and an aqueous thickener; wherein, relative to 1.0 to 6.0 parts by weight of the emulsifier, the content of the aqueous thickener is 0.05 to 2.0 parts by weight; The emulsifier is selected from at least one of the following combinations: Combination A: A combination of glyceryl stearate and PEG-100 stearate; Combination B: A combination of cetearyl glucoside and sorbitan olive oil ester; Combination C: a combination of cetearyl alcohol, dicetearyl phosphate, and cetearyl polyether-10 phosphate; Combination D, glyceryl stearate; Combination E, glyceryl stearate SE; Combination F, a combination of cetearyl alcohol and cetearyl glucoside; Combination G, sorbitan sesquioleate; Combinations of H, arachidonic acid, behenol, and arachidonic acid glucoside; Combination I, cetyl alcohol, glyceryl stearate, PEG-75 stearate, cetyl alcohol polyether-20 and stearyl alcohol polyether-20; Combination J, a combination of C14-22 alcohol and C12-20 alkyl glucoside; The aqueous thickener is Sclerotium sclerotium gum; In some embodiments, the emulsifier has a mass percentage content of 2.0 to 4.0 parts by weight; and / or, The mass ratio of the emulsifier to the sclerotium gum is (1~80):1; preferably (2~5):1.

[0009] Secondly, the present invention also provides a cosmetic formulation comprising the stable emulsifying composition as described in the foregoing embodiments.

[0010] In some embodiments, the cosmetic formulation further includes an acidic active ingredient; the acidic active ingredient is selected from at least one of α-hydroxy acids, β-hydroxy acids, and polyhydroxy acids; and / or, The pH value of the cosmetic preparation is 3.5 to 4.2.

[0011] In some embodiments, the dosage form of the cosmetic formulation includes at least one of a face mask, a face cream, and a lotion.

[0012] Thirdly, the present invention also provides a method for preparing the stable emulsified composition as described in the foregoing embodiments, comprising: S1, the aqueous thickener is mixed with water, heated and stirred to obtain an aqueous phase; S2, the emulsifier is heated and dissolved until transparent to obtain an oil phase; S3, the aqueous phase is added to the oil phase, mixed and stirred to emulsify, and the stable emulsified composition is obtained; Preferably, in step S3, the oil phase and the water phase are heated to 75°C to 85°C respectively before being mixed.

[0013] Fourthly, the present invention also provides a method for preparing a cosmetic formulation as described in the foregoing embodiments, comprising: S4, providing a stable emulsified composition as described in the foregoing embodiments; S5, the acidic active ingredient is added to the stabilized emulsion composition, and after mixing, the pH value of the system is adjusted to 3.5~4.2 using a pH adjuster to obtain the cosmetic formulation; Preferably, in step S5, the acidic active ingredient is added after the stable emulsion composition has been cooled to 40°C~50°C.

[0014] Fifthly, the present invention also provides the use of the stable emulsifying composition as described in the foregoing embodiments in the preparation of cosmetics containing acid-resistant active ingredients.

[0015] In some embodiments, the acidic active ingredient is selected from at least one of α-hydroxy acids, β-hydroxy acids, and polyhydroxy acids; Preferably, the α-hydroxy acid includes at least one selected from glycolic acid, lactic acid, citric acid, malic acid, tartaric acid, and mandelic acid; more preferably, the α-hydroxy acid is glycolic acid. Preferably, the β-hydroxy acid is salicylic acid; Preferably, the polyhydroxy acid includes at least one of gluconolactone, lactobionic acid, and gluconolactone.

[0016] In some embodiments, the cosmetic is a cosmetic used for keratin renewal, improving skin texture, or anti-aging.

[0017] Compared to existing technologies, the emulsified composition provided by this invention contains high concentrations of glycolic acid and other components, which can lead to a highly acidic (low pH) and strong ionic environment, easily disrupting conventional emulsification systems. This invention constructs a robust water-oil interface film with high steric hindrance using specific emulsifiers, and combines this with sclerotium gum to maintain its intact rheological structure and charge suspension capability in a free, strongly acidic environment. The synergistic effect of these two components effectively resists the erosion of the system structure by strong acids, completely solving the problems of demulsification, layering, oil separation, sudden viscosity drop, or discoloration that are common in existing technologies, thus endowing the composition with excellent long-term shelf-life stability.

[0018] The emulsified composition of this invention breaks through the limitations of existing technologies that require "reducing acid concentration (sacrificing efficacy)" or "using non-emulsified systems such as pure water / gels" to compromise stability. The three-dimensional stable network composed of specific emulsifiers and sclerotium gum not only stably supports high concentrations of acidic components but also perfectly overcomes the poor absorbency, lack of oiliness, and severe stickiness of traditional non-emulsified matrices, ultimately giving the product a refreshing, delicate, soft, and highly moisturizing superior skin feel. Detailed Implementation

[0019] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0020] This application provides a stable emulsifying composition designed to address the technical challenges of demulsification, layering, and thickening failure caused by high concentrations of polar acid active ingredients. The stable emulsifying composition comprises water, an emulsifier, and an aqueous thickener; the components of the stable emulsifying composition are shown in Table 1. Table 1. Components and their corresponding parts by weight

[0021] The emulsifier is limited to 1.0 to 6.0 parts by weight. For example, it can be 1.0 part by weight, 1.5 parts by weight, 2.0 parts by weight, 2.5 parts by weight, 3.0 parts by weight, 3.5 parts by weight, 4.0 parts by weight, 4.5 parts by weight, 5.0 parts by weight, 6.0 parts by weight, etc. The aqueous thickener (sclerotium sclerotium gum) is limited to 0.05 to 2.0 parts by weight. For example, it can be 0.05 parts by weight, 0.1 parts by weight, 0.3 parts by weight, 0.5 parts by weight, 0.8 parts by weight, 1.0 parts by weight, 1.2 parts by weight, 1.5 parts by weight, 1.8 parts by weight, 2.0 parts by weight, etc.

[0022] To maintain physical stability in harsh environments containing high concentrations of acidic components, this approach rigorously screened emulsifier combinations. The emulsifier combinations were selected from at least one of combinations A to J, as detailed in Table 2: Table 2. Emulsifier Combinations (A~J)

[0023] More importantly, this solution uses sclerotium sclerotium gum as the core aqueous thickener. Due to its unique non-ionic rod-shaped triple helix macromolecular structure, sclerotium sclerotium gum can maintain the integrity of its rheological structure and does not undergo hydrolysis even in a free, strongly acidic environment. The three-dimensional network formed by sclerotium sclerotium gum provides spatial confinement for the droplets encapsulated by the aforementioned specific emulsifier. The precise ratio of the two fundamentally eliminates Brownian motion and aggregation of droplets, giving the system extreme stability in highly acidic environments.

[0024] In summary, the specific emulsifier and sclerotium gum provided in this embodiment synergistically construct a high-strength water-oil interface film and a stable spatial rheological network, effectively resisting the damage to the physical structure caused by high-concentration acidic components and a low-pH, strong ionic environment. This completely solves the problems of demulsification, layering, and viscosity failure, ensuring long-term stability. Simultaneously, the precisely controlled low-pH environment maintains the high activity of free acids and the skin-renewing effect. This composition also overcomes the stickiness defects of traditional high-acid products, providing a refreshing, delicate, and moisturizing user experience.

[0025] In a preferred embodiment of this application, in order to further resist the erosion of the system interface by high concentrations of polar free acid, the emulsifier combination is further preferably a compound combination of combination D, combination F and combination I.

[0026] Studies have found that in strongly acidic systems containing high concentrations of acidic components, the interfacial films formed by conventional single emulsifiers or ordinary dual-compound emulsifiers are highly susceptible to defects and rupture under strong ionic attack. This invention employs the aforementioned specific triple-compound emulsification system, enabling emulsifier molecules with different molecular spatial conformations, carbon chain lengths, and hydrophilic and lipophilic properties to undergo highly ordered cooperative self-assembly at the water-oil interface. Specifically, combination D (glyceryl stearate) provides the basic lipophilic end arrangement; combination F (cetearearyl alcohol and cetearyl glucoside) enhances the thickness and flexibility of the interfacial film through liquid crystal forming ability; and combination I (cetearyl alcohol, glyceryl stearate, PEG-75 stearate, cetyl alcohol polyether-20, and stearyl alcohol polyether-20) utilizes its highly sterically hindered polymeric polyether structure to form a three-dimensional protective layer around the interface.

[0027] This multidimensional complementary intercalation creates a dense, multilayered liquid crystal network and a high-strength, rigid composite interface film at the interface. This dense composite interface film not only significantly enhances the steric hindrance and charge repulsion between emulsion droplets but also effectively prevents highly reactive free acid molecules from physically penetrating and damaging the interior of the emulsion droplets. Compared to conventional emulsion systems, the specific compound system composed of combination D, combination F, and combination I provides superior stability for the composition's physical state under long-term storage and extreme environments such as high temperatures, fundamentally preventing microscopic aggregation and macroscopic oil separation and stratification.

[0028] In a further preferred embodiment of this application, in order to achieve a perfect balance between excellent physical stability and superior skin feel, the relative weight parts of the emulsifier are preferably 2.0 to 4.0 parts by weight. For example, it can be 2, 3, 4, etc. Within this concentration range, the system can construct a sufficiently strong water-oil interface film in a high-concentration acid environment, while effectively avoiding whitening and skin barrier damage caused by surfactant overload.

[0029] To maximize the synergistic effect of the components in the stable system, this application strictly defines the ratio of the core structure-active substances. The mass ratio of the emulsifier combination to the sclerotium tumefaciens gum is controlled within (1~80):1, for example, it can be 1:1, 5:1, 8:1, 12:1, 15:1, 20:1, 25:1, 28:1, 32:1, 36:1, 40:1, 80:1, etc. Further preferred is (2~5):1. For example, it can be 2:1, 3:1, 4:1, 5:1, etc. Research shows that the microscopic interface constructed by the surfactant needs to match the three-dimensional rheological network of the macromolecular polymer in the external phase. Within the above specific mass ratio range, the nonionic triple-helix structure of the sclerotium tumefaciens gum can form a spatially suspended mesh of optimal density, which provides perfect spatial confinement for the droplets encapsulated by the emulsifier. The precise ratio of the two fundamentally eliminates the Brownian motion and Austaunch ripening of droplets, giving the system extreme stability in a highly acidic environment.

[0030] In addition to providing the above-mentioned stable emulsifying composition, this application also provides a cosmetic formulation comprising the aforementioned stable emulsifying composition.

[0031] In conventional daily chemical product development, thickeners and emulsifiers are usually combined to maintain the physical state of the system. However, when cosmetic formulations need to carry specific components with strong destructive properties or high ionic strength, existing conventional emulsification systems are prone to physical structural collapse, such as demulsification, layering, oil separation, and a sudden drop in viscosity. If, in order to compromise formulation stability, a non-emulsifying agent such as a simple aqueous solution or hydrogel is used as the formulation base, poor absorption, lack of oily moisturizing properties, and a severely sticky feel are common unpleasant user experiences.

[0032] The cosmetic formulation provided in this application effectively resolves the technical contradiction between carrying capacity and excellent skin feel by using the aforementioned stable emulsified composition synergistically constructed from a specific emulsifier and sclerotium tsulphureus gum as the core matrix of the product. This cosmetic formulation utilizes the unique tough multilayer liquid crystal composite interface film and nonionic rod-shaped triple helix rheological network of the stable emulsified composition to ensure both physical and chemical stability during long-term storage and under extreme temperature conditions. More importantly, this cosmetic formulation effectively overcomes the stickiness of traditional products containing high concentrations of acid, utilizing the oil components in the system to provide suitable occlusive moisturizing effects, and leveraging the rod-shaped triple helix polysaccharide structure of sclerotium tsulphureus gum to impart excellent spreadability to the formulation. When using this cosmetic formulation, consumers not only obtain significant active efficacy but also experience a refreshing, delicate, and soft skin feel. Depending on actual application needs, the cosmetic formulation can be prepared into various suitable topical dosage forms such as masks, creams, lotions, or serums.

[0033] In a preferred embodiment of this application, in order to meet the care needs of people with different skin types and different usage scenarios, the dosage form of the cosmetic preparation can be further specified as a face mask, face cream, lotion or serum.

[0034] In a preferred embodiment of this application, the cosmetic formulation further includes an acidic active ingredient; the acidic active ingredient is selected from at least one of α-hydroxy acids, β-hydroxy acids, and polyhydroxy acids; and / or, the pH value of the cosmetic formulation is 3.5 to 4.2. For example, it can be pH 3.5, pH 3.6, pH 3.7, pH 3.8, pH 3.9, pH 4.0, pH 4.1, pH 4.2, etc.

[0035] The aforementioned acidic active ingredients (such as α-hydroxy acids) are highly effective keratinocyte exfoliants. In practical applications, these ingredients require a relatively acidic environment to effectively exfoliate the stratum corneum and promote keratin renewal. However, according to cosmetic safety regulations, the pH value of such end products cannot be lower than 3.5. Therefore, in order to maximize the exfoliating efficacy of acidic ingredients while ensuring legal compliance and safety, this application strictly controls the final pH value of the cosmetic formulation within the specific range of 3.5 to 4.2.

[0036] Meanwhile, the addition of high-concentration acidic active ingredients leads to a low pH state of 3.5–4.2 in the system. This highly acidic and ionic environment caused by high-concentration acid poses an extremely stringent challenge to the physical structure of conventional formulations. The cosmetic formulation of this application benefits from its internal high-strength composite interfacial film and three-dimensional network synergistically constructed by specific emulsifiers and sclerotium gum, which can effectively resist the strong acid erosion caused by high-concentration acidic ingredients and maintain the integrity of its rheological structure in this extreme low pH environment.

[0037] This formulation successfully balances the stable carrying capacity of high-concentration acidic components with the long-term shelf-life stability of the product. While ensuring compliant and highly efficient keratin renewal activity, it completely avoids the risks of formulation deterioration such as demulsification, layering, or sudden drop in viscosity.

[0038] In a preferred embodiment of this application, the dosage form of the cosmetic preparation includes at least one of a face mask, a face cream, and a lotion.

[0039] In the development of conventional high-concentration acidic products, due to the severe damage of the emulsion interface caused by the strong acid environment, traditional formulas often have to compromise and use pure water or non-emulsified gel matrix as the carrier form. This results in products with poor absorption, lack of oil moisturizing properties, and a severely sticky feel after application, among other undesirable sensory defects.

[0040] This application successfully overcomes this dosage form limitation by employing the aforementioned stable emulsifying composition with extremely strong acid resistance as a matrix framework. This underlying emulsifying architecture possesses extremely high formulation tolerance and rheological adjustability. In practical applications, those skilled in the art can, while maintaining the integrity and stability of the core emulsifying network, use conventional methods (such as appropriately adjusting the proportion of the aqueous phase epitaxy, the volume fraction of the oil phase contents, or moderately fine-tuning the content of sclerotium tumefaciens gum) to directionally control the macroscopic viscosity and rheological characteristics of the system. This allows for the flexible preparation of the cosmetic formulation into various classic dosage forms containing oil phase components, such as creams with a certain yield stress, emulsions with good fluidity, or facial masks that are easy to spread or impregnate with a film.

[0041] Formulating these products into creams, lotions, or masks not only allows them to uniformly and stably carry highly active acidic substances, but more importantly, the lipid phase components within the system provide the necessary occlusive moisturizing effect for the skin, significantly improving dryness. At the same time, the three-dimensional stable network composed of specific emulsifiers and sclerotium gum effectively neutralizes the stickiness of high-concentration acidic components during application, giving the final product a refreshing, delicate, and soft sensory experience, meeting the usage needs of different users in daily and intensive care scenarios.

[0042] This application also provides a method for preparing the aforementioned stable emulsified composition. The core process logic of this method lies in prioritizing the self-assembly of a high-strength interfacial film and the construction of a spatial rheological network through specific physical and thermodynamic steps before introducing highly destructive environmental factors, thereby forming a pre-emulsified matrix framework with extremely high structural rigidity. Specifically, it includes the following steps: S1, the aqueous thickener is mixed with water, heated and stirred to obtain an aqueous phase.

[0043] During this stage, the synergistic effect of thermal energy and mechanical shear force promotes the full hydration and swelling of the sclerotium gum molecules, allowing their unique non-ionic rod-shaped triple helix macromolecular structure to fully unfold. This pre-constructs a spatial rheological network with a three-dimensional helical support network structure in the continuous phase (aqueous phase), providing a spatial confinement basis for subsequent droplet suspension.

[0044] S2, the emulsifier is heated and dissolved until transparent to obtain an oil phase.

[0045] Since the specific compound emulsifiers selected in this application mostly have a solid or semi-solid crystalline structure at room temperature, heating them to completely melt them breaks down the crystalline structure, transforming them into an isotropic transparent liquid. This transparent state signifies a significant decrease in cohesion, allowing the emulsifier molecules to achieve extremely high fluidity and freedom.

[0046] S3, the aqueous phase is added to the oil phase, mixed and stirred to emulsify, and the stable emulsion composition is obtained.

[0047] During the mixing and emulsification stage, the highly free-flowing liquid molecules of the specific compounded emulsifiers rapidly migrate to the oil-water interface. Based on their different molecular spatial conformations and hydrophilic-lipophilic balance values, they undergo highly ordered cooperative self-assembly at the interface, forming a dense multilayer liquid crystal network and a high-strength composite interfacial film. Simultaneously, the pre-constructed sclerotium sclerotium gel three-dimensional network in the aqueous phase interpenetrates with this interfacial film, ultimately solidifying into the stable emulsified composition system of this application.

[0048] Furthermore, in step S3, the oil phase and the water phase are heated to 75°C to 85°C respectively before mixing. For example, the temperatures can be 75°C, 76°C, 77°C, 78°C, 80°C, 82°C, 83°C, 84°C, 85°C, etc.

[0049] Specifically, both phases need to be heated to a high temperature range of 75°C to 85°C. The setting of this specific thermodynamic window is crucial: on the one hand, this temperature minimizes interfacial tension; on the other hand, isothermal mixing effectively avoids the localized rapid cooling, crystallization, or precipitation of components caused by the large temperature difference when the aqueous phase merges into the oil phase. Under this ideal state of high temperature and low interfacial resistance, emulsifier molecules can align closely in optimal kinetic configuration, thereby forming a complete primary interfacial film free of microscopic physical defects. This endows the composition with robust physical properties to withstand subsequent extreme physicochemical shocks.

[0050] This application also provides a method for preparing a cosmetic formulation as described in the foregoing embodiments. The core process logic of this preparation method lies in establishing a stable physical structure first through a step-by-step construction approach, and then loading a highly active acidic component. Specifically, it includes the following steps: S4 provides a stable emulsified composition as described above.

[0051] This stable emulsion composition, as a pre-constructed matrix system, has already preferentially completed the self-assembly of a tough multilayer liquid crystal composite interface film and the construction of a sclerotium gel spatial three-dimensional rheological network under a low ionic strength and interference-free environment, thus possessing the structural basis for subsequent resistance to strong acid impact.

[0052] S5, the acidic active ingredient is added to the stabilized emulsion composition, and after mixing, the pH value of the system is adjusted to 3.5-4.2 using a pH adjuster to obtain the cosmetic formulation. For example, the pH value can be 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, etc.

[0053] During this active loading stage, because the matrix system has established a mature physical barrier, the high concentration of free acid molecules is uniformly dispersed and confined within the continuous phase, making it difficult for them to physically penetrate and disrupt the formed, robust interfacial film. Subsequently, an acid-base buffer system is established by introducing a pH adjuster, precisely locking the pH value within the compliant and efficient range of 3.5–4.2. This process sequence effectively avoids the negative interference of free strong acids on the initial emulsification process, ensuring that the final formulation, while containing a high concentration of active substances, still possesses excellent physical stability and a long shelf life.

[0054] Furthermore, in step S5, the acidic active ingredient is added after the stabilized emulsion composition has been cooled to 40°C~50°C. For example, the temperature can be 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, etc.

[0055] To ensure the ultimate stability of the high-concentration, strongly acidic system, this application precisely controls the thermodynamic window period of the acid addition process. As the system temperature gradually decreases from the high-temperature stage to the intermediate temperature range of 40℃~50℃, the interfacial film formed by the emulsifier gradually completes the phase transition, transforming from a flowing liquid film into a dense, rigid film with extremely high mechanical strength and steric hindrance. Simultaneously, the three-dimensional rheological network of the sclerotium sclerotium gum within the system also completes the physical locking and support of its conformation. If acid is added directly at the high-temperature stage, the active free acid ions under high thermal energy conditions can easily break through the not yet fully stable liquid interfacial film, thus triggering demulsification. However, the acid addition window period of 40℃~50℃ cleverly utilizes the fully matured and solidified matrix defense framework to resist the osmotic pressure of strong acid ions, while also maintaining a relatively low hydrodynamic viscosity of the system. This ensures that the added acidic components can be uniformly stirred and dispersed without trapping air bubbles, ultimately yielding an excellent product that combines strong activity and stability.

[0056] This application also provides the application of the stable emulsifying composition as described in the foregoing embodiments in the preparation of cosmetics resistant to high concentrations of acidic active ingredients.

[0057] In the field of cosmetic formulation development, while acidic active ingredients possess excellent effects in keratin renewal and skin texture improvement, their high ionic strength and highly acidic environment can easily disrupt the physical balance of conventional emulsification systems, leading to formulation deterioration. The application provided in this application utilizes the robust physical structure unique to the aforementioned stable emulsion composition to overcome this challenge.

[0058] In practical applications, this stable emulsified composition is used as a carrier matrix for cosmetics. Because the composition contains a dense, multi-layered liquid crystal network and a high-strength, rigid composite interfacial film formed by the synergistic self-assembly of specific emulsifiers, and a three-dimensional rheological support grid constructed by sclerotium gum that remains pH-independent, this highly ordered microscopic defense architecture effectively blocks the physical penetration and damage of highly active free acid molecules into the emulsion droplets. Therefore, this composition exhibits extremely strong "tolerance" to acidic active ingredients.

[0059] Applying this technology to the preparation of cosmetics containing acidic active ingredients not only ensures the physical stability of the final cosmetics under long-term storage and extreme environments such as high temperatures (fundamentally preventing microscopic aggregation and macroscopic oil separation and stratification) and maintains a high concentration of active molecules in a free state to guarantee efficacy, but also breaks through the limitation of conventional high-acid products that have to use non-emulsified hydrogel matrices to compromise stability. Through this application, formulators can successfully and stably encapsulate high-strength acidic ingredients in excellent formulations with oil phases, such as creams and lotions, thereby effectively overcoming the poor absorption, lack of occlusive moisturizing properties, and severe stickiness of traditional non-emulsified acid products. While achieving the carrying capacity of highly active ingredients, it also gives cosmetics a refreshing, delicate, and soft user experience.

[0060] In some embodiments of this application, the specific types of acidic active ingredients described in the above applications are further clarified. The acidic active ingredients are selected from at least one of α-hydroxy acids, β-hydroxy acids, and polyhydroxy acids.

[0061] Specifically, α-hydroxy acids (AHAs), as a class of water-soluble organic acids, can effectively reduce adhesion between keratinocytes. Preferably, the α-hydroxy acids include at least one selected from glycolic acid, lactic acid, citric acid, malic acid, tartaric acid, and mandelic acid.

[0062] More preferably, the α-hydroxy acid is glycolic acid. Glycolic acid is the smallest molecular weight α-hydroxy acid, possessing extremely high epidermal permeability and excellent exfoliation and anti-aging effects. However, its extremely high polarity and ionic strength also pose the highest level of challenge to the stability of the carrier matrix. The stable emulsified composition provided in this application can perfectly withstand high concentrations of glycolic acid, preventing the system from demulsifying and separating.

[0063] Furthermore, for cosmetic applications that aim to control oil and unclog pores, the β-hydroxy acid is preferably salicylic acid. Salicylic acid has excellent lipid solubility, allowing it to penetrate deep into the pores along the sebaceous glands and dissolve accumulated sebum and dead skin cells.

[0064] For applications on skin with a weak barrier function or requiring gentle care, preferably, the polyhydroxy acid includes at least one of gluconolactone, lactobionic acid, and gluconolactone. Polyhydroxy acids have a relatively large molecular size and a relatively slow transdermal penetration rate, while the multiple hydroxyl groups in their molecular structure can provide additional hydration and moisturizing effects, achieving gentle skin resurfacing.

[0065] In practical application development, those skilled in the art can rely on the stable emulsified composition provided in this application as a robust formulation base, and according to the specific skin needs of the target audience, add one of the above-mentioned specific acidic substances alone, or combine and add the above-mentioned acidic active ingredients with different transdermal layers and efficacy focuses (such as the combination of glycolic acid and salicylic acid), so as to achieve multi-dimensional skin improvement effects while ensuring the long-term shelf-life stability of the product system.

[0066] In a preferred embodiment of this application, the specific efficacy and use of the cosmetic in the application are further clarified, namely, the cosmetic is used for keratin renewal, skin improvement or anti-aging.

[0067] In the field of functional cosmetics, achieving significant keratin renewal, skin texture improvement, and deep anti-aging often relies on the sustained penetration and action of high concentrations of acidic active ingredients (such as high concentrations of glycolic acid). These ingredients accelerate the exfoliation of dead skin cells by interfering with desmosome connections between keratinocytes and further stimulate the synthesis of the dermal matrix. However, the extremely low pH and strong ionic strength inherent in high-concentration acid solutions often cause conventional emulsion systems to break down, separate, and lose viscosity during storage or application, ultimately leading to uneven distribution of active ingredients, a surge in localized irritation, and loss of product efficacy.

[0068] This application applies the aforementioned stable emulsifying composition with extremely strong physical rigidity and chemical resistance to the preparation of high-efficacy cosmetics, perfectly solving the problem of carrying high-concentration free acids. This stable emulsifying system utilizes a dense, multi-layered liquid crystal composite interface film and a three-dimensional suspended network constructed from sclerotium gum to uniformly and stably anchor free acid molecules in the continuous phase. This not only fundamentally prevents microscopic aggregation and macroscopic oil separation and stratification, ensuring sufficient distribution and high activity of acidic molecules throughout the shelf life; more importantly, the lipid components and special three-dimensional network contained in the emulsifying matrix effectively neutralize the stickiness and irritation caused by high concentrations of fruit acids when applied by consumers.

[0069] Using the stable emulsified composition platform of this application, formulators can successfully develop lotions or creams that combine high acid-carrying capacity with an excellent sensory experience. The resulting cosmetics can effectively exert their anti-aging effects, such as accelerating keratin renewal, improving rough and dull skin texture, and reducing fine lines, while remaining safe and gentle, achieving a balance between powerful skincare and a pleasant skin feel.

[0070] The present invention will be further illustrated below with specific embodiments. However, it should be understood that these embodiments are merely for the purpose of more detailed illustration and should not be construed as limiting the present invention in any way.

[0071] Information on raw materials and equipment used in the examples and comparative examples: 1. Raw material sources: Glycolic acid was purchased from Guangzhou Rongdao; salicylic acid was purchased from Shanghai Zhenheng; lactobionic acid was purchased from Guangzhou Huiying; sodium hydroxide was purchased from Shanghai Faenkai; sclerotium gum was purchased from Shanghai Ronghai / Shanghai Qianfei / Guangzhou Aoyuan; MONTANOV 68MB was purchased from Guangzhou Baihaobo; glyceryl stearate was purchased from Shanghai Xierui; EMULIUM DELTA was purchased from Shanghai Puen.

[0072] 2. Instruments and equipment: Refer to Table 3 below.

[0073] Table 3. Equipment-related Information

[0074] Preparation of Examples 1-8 and Comparative Examples 1-20 The examples and comparative examples in this section provide a series of oil-in-water (O / W) face cream compositions containing glycolic acid, salicylic acid, or lactobionic acid. Different combinations of emulsifiers and thickeners, along with varying amounts of acidic ingredients, were formulated to prepare corresponding test samples for subsequent systematic investigation of their stability under extreme conditions and their feel on the skin.

[0075] 1. Formula composition: Table 4. Formulations for each group in the examples

[0076] Table 5. Comparative Example Groups 1 (A, B, Thickener, Emulsifier)

[0077] Table 6. Comparative Example Groups 2 (C, D, E)

[0078] The formulations of Examples 1-8: the specific ingredients and their mass percentage ratios are shown in Table 4.

[0079] Formulas for Comparative Examples 1-20: Specific ingredients and mass percentage ratios are shown in Tables 5 and 6.

[0080] 2. Preparation process: The preparation processes for each embodiment and comparative example were performed according to the following steps: (1) A phase composition preparation: Add water and sodium hydroxide to beaker 1, mix and stir until transparent and clear, cool and then add a mixture of glycolic acid / lactobionic acid / salicylic acid and propylene glycol; (2) B phase composition: Add all components except boiling water to beaker 2 in sequence, stir and disperse, then add water, and place the beaker in an 80℃ water bath and stir at medium speed until a homogeneous liquid is formed. (3) Preparation of C phase components, thickener and emulsifier composition: Add the raw materials to beaker 3, then place the beaker in an 80℃ water bath and keep it warm until the solid particles melt into a transparent liquid. Stir evenly and set aside. (4) Emulsification and homogenization: Pour the mixed solution from beaker 3 into beaker 2 and homogenize at a speed of 8000~9000 rpm for 1~3 min to obtain the initial material; (5) Cooling and stirring: Stir the initial material at medium speed until the temperature drops below 50°C. Then, add the mixed liquid, D phase component, and E phase component from beaker 1 in sequence and stir until homogeneous. After the temperature drops to room temperature, collect the prepared O / W face cream.

[0081] Experimental Example 1: pH Value Detection In this experimental example, the pH value of the face cream samples prepared in each embodiment and comparative example was tested to examine the pH buffering capacity and acid-base consistency of the emulsion composition system under different formulation conditions.

[0082] 1. Experimental Method: Weigh appropriate amounts of the face cream samples prepared in Examples 1-8 and Comparative Examples 1-20 (accurate to 0.001 g) and place them in a beaker. Add 9 times the volume of purified water and stir at an appropriate speed at 25 ± 1°C until the sample is completely dispersed, forming a homogeneous 1% aqueous dispersion. Allow the system to stand until the temperature stabilizes at 25 ± 1°C. Perform two-point calibration of the pH meter using a standard buffer solution. Immerse the calibrated pH meter electrode in the prepared aqueous dispersion of the sample, ensuring that the electrode bulb is completely submerged and does not touch the bottom of the beaker. After the reading stabilizes, record the displayed pH value.

[0083] 2. Experimental Results: The pH values ​​for each group are shown in Table 7.

[0084] Table 7. pH value measurement results for each group

[0085] 3. Results Analysis: The results showed that the pH of all tested samples was within the acidic range. Most of the examples and comparative examples had pH values ​​concentrated in a narrow range of 3.92 to 4.06, indicating that the composition system has good pH buffering capacity and formulation consistency. Notably, the pH values ​​of Examples 5, 6, and 7 were significantly lower (3.62, 3.65, and 3.64, respectively), suggesting that specific component or process design can stabilize the system in a more acidic environment. In contrast, the pH value of Comparative Example 17 was significantly higher (4.77), deviating from the main range, possibly representing some formulation condition of failure or reduced effectiveness. Overall, the data indicate that this acid-resistant composition can maintain a stable acidic environment under most conditions, and that pH can be directionally and stably controlled through specific technical means.

[0086] It is worth noting that the pH values ​​of Examples 5, 6, and 7 are significantly lower (3.62~3.65). This is because Example 7 uses salicylic acid, which has a strong acidic dissociation constant, and the amounts of sodium hydroxide added (1.0% and 2.2%) and the concentration of acid in Examples 5 and 6 were controlled to extreme ratios. This further demonstrates that the emulsion matrix of the present invention can maintain the integrity of the system even in an extreme free acid environment with a pH close to 3.5.

[0087] Experiment Example 2: Stability Test In this experimental example, accelerated stability tests were conducted to examine and verify the synergistic effect of specific emulsifier and thickener combinations on the long-term physical stability of the system under extreme conditions (high and low temperatures) and at room temperature in a strongly acidic environment containing high concentrations of glycolic acid.

[0088] 1. Experimental Method: Take appropriate amounts of samples from the embodiments of the present invention, comparative samples, and commercially available high-acid face cream samples, place them in sealed containers, and place them in constant temperature environments of -15°C, room temperature, and 50°C for one month to conduct accelerated stability tests. Samples were taken on the 1st, 7th, and 30th days after the start of the test, and the appearance of the samples (such as color, shape, uniformity, etc.) was visually observed under natural light or a specified light source, and the results were recorded.

[0089] 2. Experimental Results: The stability records of each group of samples at different temperatures and time points are shown in Tables 8 and 9.

[0090] Table 8. Stability records of each group of samples in the examples and commercially available samples at different temperatures and time points.

[0091] Table 9. Stability records of each group of samples in the comparative examples at different temperatures and time points.

[0092] 3. Results Analysis: Test results show that the face creams prepared by the compositions of Examples 1-8 provided in this application maintained a normal appearance (milky white cream) after being placed under low temperature (-15℃), high temperature (50℃) and normal temperature conditions for 7 days and 30 days, respectively. No unstable phenomena such as layering, oiling, transparency or roughness were observed, demonstrating excellent acid resistance stability.

[0093] In contrast, commercially available samples exhibited significant oil exudation anomalies under normal, low, and high temperature conditions. Comparative Examples 1-20, which used other emulsifiers or water-soluble thickeners, showed a significant decrease in stability: some comparative examples exhibited roughness, oil separation, and transparency under high temperature conditions (e.g., Comparative Examples 1, 2, 3, 4, 6, 7, 11, 14, 15, etc.); others showed oil exudation or water-oil separation even at normal or low temperature conditions (e.g., Comparative Examples 5, 8, 9, 10, 12, 13, 16-20, etc.).

[0094] The results show that the composition in this experiment can effectively maintain the stability of the face cream in an acidic environment through the synergistic effect of specific emulsifiers and thickeners, while the replacement or improper combination of conventional emulsifiers or thickeners will lead to the deterioration of stability.

[0095] Experiment Example 3: Sensory Evaluation of Products In this experimental example, a consumer skin feel comparison test was conducted to examine the effectiveness of the composition of the present invention in overcoming the stickiness defect of traditional products containing high concentrations of acid, and to verify its sensory characteristics in actual use.

[0096] 1. Experimental Method: (1) Subject screening: recruit no fewer than 30 healthy Asian adult subjects aged 35-55 (who must meet the inclusion criteria such as no history of allergies and exclude pregnancy).

[0097] (2) Test design: The high acid content face cream sample prepared in Example 1 and the commercially available high acid content face cream sample were selected. A 1V1 comparison design was adopted for the left and right sides of the face. The two samples were applied in equal amounts to the symmetrical areas of the left and right sides of the subject's face.

[0098] (3) Testing Procedure: Day 1 Test: After cleansing their faces, participants applied the sample to their faces for an immediate comparison of skin feel and then immediately filled out the Day 1 questionnaire.

[0099] Day 2 test: Without cleaning the face or using any additional products, fill out the second day's questionnaire the next morning based on your own feelings to evaluate the residual skin feel and lasting effect.

[0100] Assessment scale: A 9-point Likert scale was used, with higher scores indicating stronger liking or positive feelings. The dimensional definitions of the assessment parameters for the first and second days are shown in Tables 10 and 11, respectively.

[0101] Table 10. Evaluation Parameters for Day 1

[0102] Table 11. Evaluation Parameters for the Second Day

[0103] 2. Experimental Results: The sensory evaluation scores of the example samples and commercially available samples are statistically analyzed and correspond to Table 12.

[0104] Table 12. Sensory evaluation scores of the example samples and commercially available samples.

[0105] 3. Results Analysis: Test results show that the face cream prepared in Example 1 of this invention performs equally or better than commercially available acid-containing face creams in many aspects of skin feel.

[0106] In the first day of testing, the test sample scored higher than commercially available samples in all dimensions, including texture preference, spreadability / applyability, absorption speed, refreshing feel, smoothness, and skin smoothness, especially in texture preference (7.758 vs. 7.333) and spreadability / applyability (7.788 vs. 7.515). In the second day of testing, the test sample further improved in terms of stickiness, refreshing feel, smoothness, and skin smoothness, with smoothness (8.061 vs. 7.848) and skin smoothness (8.348 vs. 8.045) both exceeding those of commercially available samples.

[0107] In summary, the face cream prepared by this composition is competitive in terms of overall skin feel, demonstrating the effectiveness of its formulation in providing a pleasant skin feel and overcoming stickiness, achieving a balance between high efficiency and a pleasant skin feel.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cosmetic preparation, characterized in that, It contains a stable emulsifying composition and an acidic active ingredient; The stabilized emulsified composition comprises water, an emulsifier, and an aqueous thickener; wherein, relative to 1.0 to 6.0 parts by weight of the emulsifier, the content of the aqueous thickener is 0.05 to 2.0 parts by weight. The emulsifier is a compound combination of combination D, combination F, and combination I; wherein combination D, combination F, and combination I are respectively: Combination D: Glyceryl stearate; Combination F: A combination of cetearyl alcohol and cetearyl glucoside; Combination I: A combination of cetyl alcohol, glyceryl stearate, PEG-75 stearate, cetyl alcohol polyether-20 and stearyl alcohol polyether-20; The aqueous thickener is Sclerotium sclerotium gum; The emulsifier is present in parts by weight of 2.0 to 4.

0. The mass ratio of the emulsifier to the sclerotium gum is (2~5):1; The acidic active ingredient is glycolic acid; The pH value of the cosmetic preparation is 3.5 to 4.

2.

2. The cosmetic preparation according to claim 1, characterized in that The dosage form of the cosmetic preparation includes at least one of face mask, face cream and lotion.

3. A method for producing the cosmetic preparation according to claim 1 or 2, characterized in that, include: S1, the aqueous thickener is mixed with water, heated and stirred to obtain an aqueous phase; S2, the emulsifier is heated and dissolved until transparent to obtain an oil phase; S3, the aqueous phase is added to the oil phase, mixed and stirred to emulsify, and the stable emulsified composition is obtained; S4, the acidic active ingredient is added to the stabilized emulsion composition, and after mixing, the pH value of the system is adjusted to 3.5~4.2 using a pH adjuster to obtain the cosmetic formulation.

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