Amino acid moisturizing facial cleanser and preparation method thereof

Abstract

The present invention discloses an amino acid moisturizing facial cleanser and a preparation method thereof, which belongs to the technical field of amino acid facial cleansers. The cleanser comprises the following raw materials in parts by weight: 10-30 parts of an amino acid surfactant, 7.4-17 parts of a moisturizing agent, 1-2 parts of a thickener, 0.1-4 parts of a skin conditioner, 0.1-0.5 parts of a pH regulator, 0.1-0.5 parts of a fragrance, 0.1-1 parts of a preservative, 0.01-0.1 parts of a chelating agent, and 49-82 parts of deionized water; the thickener comprises tragacanth gum and xanthan gum, and the mass ratio of the tragacanth gum to the xanthan gum is (3:1)-(9:1). In the present invention, the tragacanth gum and the xanthan gum synergistically improve the stability of the foam, the tragacanth gum and the xanthan gum can form a rigid-flexible network, a gel matrix having both elasticity and shear-thinning properties, and prolong the foam half-life. The tragacanth gum can also form a breathable hydration film on the skin surface, reduce water evaporation, and synergistically replenish water with the moisturizing agent.

Description

Technical Field

[0001] The present invention relates to the technical field of amino acid facial cleansers, and in particular to an amino acid moisturizing facial cleanser and a preparation method thereof. Background Art

[0002] Traditional soap-based facial cleansers, due to their high pH (9.0-10.5), damage the skin's acidic protective mantle, significantly increasing transepidermal water loss (TEWL). Long-term use can lead to skin problems such as sensitivity, redness, dryness, and scaling. Excessive degreasing causes an 18%-25% loss of intercellular lipids (ceramides and cholesterol). In hard water environments, insoluble metallic soap residues are more likely to clog pores. Long-term use can lead to barrier damage, compensatory oil production, and skin sensitivity. Furthermore, soap-based facial cleansers are incompatible with soothing and moisturizing active ingredients (such as panthenol and ceramides), severely limiting their use in sensitive skin care and long-lasting moisturizing products.

[0003] Amino acid facial cleansers are currently a mainstream choice in the cleansing market due to their mildness and safety. Their core advantage lies in their use of weakly acidic amino acid surfactants (such as sodium cocoyl glycinate and sodium lauroyl glutamate), which have a pH close to that of the natural sebum membrane (approximately 5.5-6.5). This avoids the barrier damage and tightness associated with traditional soap-based facial cleansers due to their high alkalinity.

[0004] However, traditional amino acid facial cleanser thickening systems often rely on synthetic polymers (such as carbomer and acrylic acid (ester) copolymers) or excess electrolytes (sodium chloride). While these systems can adjust viscosity, they pose irritation risks (such as pH-dependent barrier damage caused by carbomer) or insufficient foam stability (rapid foam collapse after shear thinning). In particular, thickening efficiency decreases significantly at low pH values ​​(5.0-6.5), leading to uncontrolled product flow or pumping difficulties.

[0005] Most amino acid facial cleansers available on the market rely on small molecule moisturizers (glycerin, butylene glycol, etc.), but their residence time is too short to effectively compensate for the loss of water in the stratum corneum during the cleansing process. Excessive addition can easily cause the system to become sticky or deteriorate the stability of the compatibility, resulting in the skin still feeling dry and tight after washing, which cannot meet the long-term care needs of sensitive or dry skin. Natural colloids (such as xanthan gum and gellan gum) can replace synthetic thickeners, but they have poor compatibility with amino acid surfactants and are prone to flocculation or stratification. In addition, a single colloid cannot take into account both viscosity maintenance and foam persistence, resulting in limited product practicality.

[0006] In view of the above problems in the prior art, the present invention combines many years of design and use experience in related fields to design an amino acid moisturizing facial cleanser and a preparation method thereof to overcome the above defects. Summary of the Invention

[0007] In response to the problems existing in the prior art, the present invention provides an amino acid moisturizing facial cleanser and a preparation method thereof, which have strong foam stabilization performance, slow down the foam collapse rate, have synergistic water locking-hydrating-repairing functions, have few irritating ingredients, have a high biodegradation rate, and can avoid microplastic pollution.

[0008] To achieve the above objectives, the present invention provides an amino acid moisturizing facial cleanser in a first aspect, comprising the following raw materials in parts by weight: 10-30 parts of an amino acid surfactant, 7.4-17 parts of a moisturizer, 1-2 parts of a thickener, 0.1-4 parts of a skin conditioner, 0.1-0.5 parts of a pH adjuster, 0.1-0.5 parts of a fragrance, 0.1-1 parts of a preservative, 0.01-0.1 parts of a chelating agent, and 49-82 parts of deionized water;

[0009] The thickener comprises tragacanth gum and xanthan gum, and the mass ratio of the tragacanth gum to the xanthan gum is (3:1)-(9:1).

[0010] Preferably, the moisturizing agent includes at least two of glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and Tremella polysaccharide.

[0011] Preferably, the moisturizing agent includes glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and Tremella polysaccharide;

[0012] In the amino acid moisturizing facial cleanser, the amount of 1,2-ethylene glycol is 3.2 parts by weight, and the weight ratio of tragacanth gum, glycerin, sodium hyaluronate, panthenol, and tremella polysaccharide is (1-1.7):(5-8):(0.5-1):(2-4):(0.3-0.7).

[0013] Preferably, the amino acid surfactant is selected from at least two of sodium cocoyl glycinate, potassium cocoyl glycinate, disodium cocoyl glutamate, sodium lauroyl glutamate and sodium lauroyl sarcosinate.

[0014] Preferably, the preservative is selected from one of phenoxyethanol, caprylhydroxamic acid, and p-hydroxyacetophenone;

[0015] The chelating agent is disodium EDTA;

[0016] The fragrance is a daily fragrance.

[0017] Preferably, the pH adjuster is lactic acid or citric acid.

[0018] Preferably, the skin conditioning agent is selected from at least two of dipotassium glycyrrhizate, witch hazel extract, and dipropylene glycol.

[0019] The present invention also provides a method for preparing an amino acid moisturizing facial cleanser, comprising the following steps:

[0020] (1) Premix tragacanth gum and glycerin in proportion, and shear disperse in deionized water at 50-60°C at a speed of 3000-5000 rpm for 10-15 minutes;

[0021] (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid;

[0022] (3) Heat the colloid to 65-80°C, add amino acid surfactant, and stir until dissolved;

[0023] (4) Cool down to 35-40℃, add moisturizer first, then add skin conditioner, fragrance, chelating agent, preservative and mix well;

[0024] (5) Adjust the pH to 5.5-6.5 with a pH regulator;

[0025] (6) At a pressure of 10-15 MPa, the amino acid moisturizing facial cleanser is obtained by homogenizing and filling.

[0026] The benefits of this invention are:

[0027] 1. The thickener composed of tragacanth gum and xanthan gum in the present invention plays a synergistic role in improving the stability of foam. The β-(1→4)-linked D-galacturonic acid main chain and neutral sugar side chains in the tragacanth gum molecular chain can form a highly viscoelastic three-dimensional network skeleton in the aqueous phase through hydrogen bonds and van der Waals forces, providing foam support and enhancing foam stability. At the same time, xanthan gum dynamically cross-links with the linear chain segments of tragacanth gum through its anionic properties and helical molecular structure, further strengthening the network density and forming a gel matrix with both elasticity and shear-thinning properties. The shear-thinning property causes the amino acid moisturizing facial cleanser to become thinner when pumped out by external force, making it easier to use. When the external force disappears, the viscoelasticity is quickly restored, maintaining the stability of the foam, extending the half-life, preventing the foam from collapsing too quickly, and improving the user experience. The ion sensitivity of xanthan gum complements the pH stability of tragacanth gum, so that the system maintains stable rheological properties within the pH range of 5.5-6.5.

[0028] 2. The tragacanth gum in the present invention is a natural high-molecular polysaccharide. The β-1,4-glycosidic bonds in its molecular chain form a three-dimensional network structure, forming a breathable hydration film on the skin surface, reducing water evaporation (TEWL reduction). At the same time, its polar groups (hydroxyl and carboxyl groups) combine with small molecule moisturizers such as glycerol and sodium hyaluronate through hydrogen bonds, enhancing the latter's directional penetration and retention ability in the stratum corneum, thereby improving the moisturizing effect.

[0029] 3. In this invention, glycerin captures environmental moisture through hygroscopic action, and after combining with the tragacanth gum network, it delays volatilization and forms a dynamic moisturizing layer; low molecular weight (30-100 kDa) sodium hyaluronate can penetrate deep into the stratum corneum and synergistically work with tragacanth gum to fill the intercellular spaces and improve skin hydration; after panthenol is converted into pantothenic acid, it can repair the lipid barrier, enhance the water-locking durability of the tragacanth gum-glycerin system, and give the system a repair function; Tremella polysaccharide contains mannuronic acid and glucuronic acid, which can cross-link with the sugar chains of tragacanth gum, enhance membrane flexibility and protect against free radical damage.

[0030] 4. The natural pH adaptability of the tragacanth gum in the present invention (stable at 5.0-7.5) can avoid the process defect of carbomers requiring alkaline neutralization, thereby reducing the residual irritating ingredients (such as triethanolamine), causing less irritation to the skin, and the biodegradation rate can reach 91% (OECD 301B), which can avoid microplastic pollution. DETAILED DESCRIPTION

[0031] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to specific embodiments.

[0032] The first aspect of the present invention provides an amino acid moisturizing facial cleanser, comprising the following raw materials in parts by weight: 10-30 parts of an amino acid surfactant, 7.4-17 parts of a moisturizer, 1-2 parts of a thickener, 0.1-4 parts of a skin conditioner, 0.1-0.5 parts of a pH adjuster, 0.1-0.5 parts of a fragrance, 0.1-1 parts of a preservative, 0.01-0.1 parts of a chelating agent, and 49-82 parts of deionized water.

[0033] The thickeners include tragacanth gum and xanthan gum; in the amino acid moisturizing facial cleanser, the mass ratio of tragacanth gum to xanthan gum is (3:1)-(9:1).

[0034] The β-(1→4)-linked D-galacturonic acid main chain and neutral sugar side chains in the tragacanth gum molecular chain of the present invention can form a highly viscoelastic three-dimensional network skeleton in an aqueous phase through hydrogen bonds and van der Waals forces. Xanthan gum, through its anionic properties and helical molecular structure, dynamically cross-links with the linear chain segments of tragacanth gum, further strengthening the network density and forming a gel matrix with both elasticity and shear-thinning properties. The highly viscoelastic three-dimensional network skeleton of tragacanth gum provides foam support, and the shear-thinning property of xanthan gum ensures that the facial cleanser is easily dispersed when pumped out and quickly recovers its viscoelasticity after use. The two synergistically enhance the stability of the foam and extend the foam stability half-life.

[0035] Furthermore, the ion sensitivity of xanthan gum complements the pH stability of tragacanth gum, maintaining stable rheological properties within a pH range of 5.5-6.5. Carbomer thickeners require an alkaline neutralizer (such as triethanolamine). If not properly cleansed, triethanolamine residues can disrupt the skin's microecological balance. The present invention utilizes tragacanth gum, which has good natural pH adaptability (stable between 5.0 and 7.5), to avoid the process drawbacks of carbomers requiring alkaline neutralization, thereby reducing residual irritants (such as triethanolamine). Compared to the low biodegradability (approximately 40%) of acrylate polymers (such as SEPINOV™), the thickeners of the present invention have a biodegradability of up to 91% (OECD 301B), thus preventing microplastic contamination.

[0036] The moisturizing agent includes at least two of glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and tremella polysaccharide. The moisturizing agent includes glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and tremella polysaccharide. In the amino acid moisturizing facial cleanser, 1,2-ethylene glycol is 3.2 parts by weight, and the weight ratio of tragacanth gum, glycerin, sodium hyaluronate, panthenol, and tremella polysaccharide is (1-1.7): (5-8): (0.5-1): (2-4): (0.3-0.7).

[0037] The tragacanth gum in this invention not only functions as a thickener but also as a natural moisturizing synergist, creating a synergistic effect with the moisturizers in the formula. The β-1,4-glycosidic bonds within the tragacanth gum molecular chain form a three-dimensional network, forming a breathable hydration membrane on the skin surface. While reducing water evaporation (TEWL), its polar groups (hydroxyl and carboxyl groups) bind to small molecule moisturizers such as glycerol and sodium hyaluronate through hydrogen bonds, enhancing their directional penetration and retention in the stratum corneum, improving their moisturizing effect.

[0038] Specifically, glycerol in this invention captures environmental moisture through hygroscopic action, then binds to the tragacanth gum network to delay volatilization, forming a dynamic moisturizing layer. Low-molecular-weight sodium hyaluronate penetrates deep into the stratum corneum and synergizes with tragacanth gum to fill intercellular spaces and improve skin hydration. Panthenol, converted to pantothenic acid, repairs the lipid barrier and enhances the long-lasting water retention of the tragacanth gum-glycerol system. Tremella polysaccharides contain mannuronic acid and glucuronic acid, which can cross-link with the sugar chains of tragacanth gum, enhancing membrane flexibility and protecting against free radical damage. Tragacanth gum reduces TEWL through a triple mechanism of physical barrier construction, lipid regulation, and anti-inflammatory repair. Its polysaccharide structure forms a multidimensional synergistic network with moisturizers with different functions (glycerol, HA, tremella polysaccharides, etc.), achieving an integrated moisturizing effect of "moisture absorption, water retention, and repair."

[0039] The amino acid surfactant is selected from at least two of sodium cocoyl glycinate, potassium cocoyl glycinate, disodium cocoyl glutamate, sodium lauroyl glutamate and sodium lauroyl sarcosinate; the preservative is selected from one of phenoxyethanol, caprylhydroxamic acid and p-hydroxyacetophenone; the pH adjuster is selected from lactic acid or citric acid; the skin conditioner is selected from at least two of dipotassium glycyrrhizate, witch hazel extract and dipropylene glycol; the chelating agent is disodium EDTA; and the fragrance is daily fragrance.

[0040] The present invention also provides a method for preparing an amino acid moisturizing facial cleanser, comprising the following steps:

[0041] (1) Premix tragacanth gum and glycerin in proportion, and shear disperse in a 50-60°C aqueous phase at a speed of 3000-5000 rpm for 10-15 minutes;

[0042] (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid;

[0043] (3) Heat the colloid to 65-80°C, add amino acid surfactant, and stir until dissolved;

[0044] (4) Cool down to 35-40℃, add moisturizer first, then add skin conditioner, fragrance, chelating agent, preservative and stir evenly at a stirring speed of 25-40rpm;

[0045] (5) Adjust the pH to 5.5-6.5 with a pH regulator;

[0046] (6) At a pressure of 10-15 MPa, the amino acid moisturizing facial cleanser is obtained by homogenizing and filling.

[0047] Because glue tragacanth gum directly contacts water phase and can cause particle aggregation, shear dispersion energy consumption increases, and the dispersion process duration is extended, and simultaneously can affect the sufficient swelling of the subsequent xanthan gum added.Therefore in the present invention, glue tragacanth gum and glycerol are first premixed, improve dispersibility, make glue tragacanth gum quickly and fully swell, form a uniform and stable colloidal dispersion system, reduce system viscosity, avoid the caking of glue tragacanth gum in subsequent process or phase separation while being convenient to the subsequent compounding of ingredients such as sodium hyaluronate, panthenol.Wherein glycerol is combined with the polysaccharide chain of glue tragacanth gum by hydrogen bond, forms " moisture absorption-locking " dynamic network, enhances the instantaneous moisture retention of system.

[0048] The specific embodiments are as follows

[0049] Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the materials, reagents, etc. used are all commercially available unless otherwise specified.

[0050] In the following examples and comparative examples, the tragacanth gum was a highly transparent tragacanth gum (CAS No. 9000-65-1), model HY-126D, with a purity of >95%, obtained from Shandong Dongfang Hongye Chemical Co., Ltd.

[0051] Xanthan gum is highly transparent xanthan gum with a purity of >95%, sourced from Shandong Dongfang Hongye Chemical Co., Ltd.

[0052] Example 1-Example 5 and Comparative Example 1-Comparative Example 5

[0053] The present invention provides an amino acid moisturizing facial cleanser, having a total weight of 100 parts. The components and weight portions of Examples 1 to 5 and Comparative Examples 1 to 5 are selected as shown in Table 1. The pH regulator, skin conditioner, fragrance, chelating agent, and preservative components used in Examples 1 to 5 and Comparative Examples 1 to 5 are the same. Specifically, the pH regulator is citric acid, the skin conditioner is a mixture of 2 parts of dipotassium glycyrrhizate and 1.5 parts of dipropylene glycol, the fragrance is a daily fragrance, the chelating agent is disodium EDTA, and the preservative is phenoxyethanol.

[0054] The amino acid surfactant and moisturizing agent components used in Examples 1 to 5 and Comparative Examples 1 to 5 are the same, specifically, the amino acid surfactant is 30 parts, including 40% by mass of sodium cocoyl glycinate (mass concentration of 35%) and 60% by mass of sodium lauroyl sarcosinate (mass concentration of 28%); the moisturizing agent is a mixture of 1,2-ethylene glycol, glycerin, sodium hyaluronate, tremella polysaccharide, and panthenol, and the moisturizing agent is 3.2 parts of 1,2-ethylene glycol, 6 parts of glycerin, 0.75 parts of sodium hyaluronate, 0.5 parts of tremella polysaccharide, and 3 parts of panthenol.

[0055] Examples 1 to 5 and Comparative Examples 1 to 5 differ only in the composition, weight parts, and weight parts of the thickener, as follows:

[0056] Example 1

[0057] The thickener in this embodiment is a mixture of 0.9 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, with the mass ratio of tragacanth gum to xanthan gum being 3:1.

[0058] This embodiment also provides a method for preparing an amino acid moisturizing facial cleanser, comprising the following steps:

[0059] (1) Pre-dispersed tragacanth gum: pre-mix tragacanth gum and glycerol in proportion and shear disperse in a 55°C aqueous phase (speed 4000 rpm, time 15 minutes);

[0060] (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid;

[0061] (3) Heat the colloid to 80°C, add amino acid surfactant, and stir until dissolved;

[0062] (4) Cool down to 40°C, add sodium hyaluronate, panthenol, Tremella polysaccharide in sequence, then add skin conditioner, fragrance, chelating agent, preservative, keep stirring at 30 rpm, and stir evenly;

[0063] (5) Adjust the pH to 6 with citric acid;

[0064] (6) After homogenization at 10 MPa, the amino acid moisturizing facial cleanser is bottled.

[0065] Example 2

[0066] The thickener in this embodiment is a mixture of 1.16 parts by weight of tragacanth gum and 0.24 parts by weight of xanthan gum, with a mass ratio of tragacanth gum to xanthan gum being 5:1.

[0067] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0068] Example 3

[0069] The thickener in this embodiment is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, with a mass ratio of tragacanth gum to xanthan gum being 5:1.

[0070] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0071] Example 4

[0072] The thickener in this embodiment is a mixture of 1.5 parts by weight of tragacanth gum and 0.25 parts by weight of xanthan gum, with a mass ratio of tragacanth gum to xanthan gum being 6:1.

[0073] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0074] Example 5

[0075] The thickener in this embodiment is a mixture of 1.8 parts by weight of tragacanth gum and 0.2 parts by weight of xanthan gum, with a mass ratio of tragacanth gum to xanthan gum being 9:1.

[0076] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0077] Comparative Example 1

[0078] The thickener in this comparative example is 1.8 parts by weight of tragacanth gum.

[0079] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that in this comparative example, tragacanth gum and glycerin were premixed and stirred until they were completely swollen to form a uniform colloid, and no xanthan gum was added.

[0080] Comparative Example 2

[0081] The thickener in this comparative example is 1.8 parts by weight of xanthan gum.

[0082] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that in this comparative example, glycerin and xanthan gum were mixed in an aqueous phase and stirred until they were completely swollen to form a uniform colloid.

[0083] Comparative Example 3

[0084] The thickener in this comparative example is a mixture of 1.0 parts by weight of tragacanth gum and 0.5 parts by weight of xanthan gum, with the mass ratio of tragacanth gum to xanthan gum being 2:1.

[0085] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1.

[0086] Comparative Example 4

[0087] The thickener in this comparative example is a mixture of 2.1 parts by weight of tragacanth gum and 0.1 parts by weight of xanthan gum, with the mass ratio of tragacanth gum to xanthan gum being 21:1.

[0088] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1.

[0089] Comparative Example 5

[0090] The thickener in this comparative example is a mixture of 1.8 parts by weight of tragacanth gum and 0.05 parts by weight of xanthan gum, with the mass ratio of tragacanth gum to xanthan gum being 36:1.

[0091] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1.

[0092] Table 1 Basic component formula

[0093]

[0094] The amino acid moisturizing facial cleansers prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were tested for foam stability.

[0095] 1. The test standards and methods for foam stability half-life (min) and initial foam height (mm) are as follows:

[0096] (1) Sample preparation: amino acid moisturizing facial cleanser and deionized water were mixed in a mass ratio of 1:9 and allowed to stand at a constant temperature of 25 ± 0.5 °C for 24 h to eliminate shear history;

[0097] (2) Foam generation: A Ross-Miles foam meter (compliant with GB / T 29679-2013) was used, the test temperature was controlled at 25 ± 0.5 °C, and 500 mL of sample was dropped vertically from a height of 900 mm to the bottom receiving tank at a constant flow rate (200 ± 5 mL / min);

[0098] (3) Determination of initial foam volume: record the initial height of the foam column H0 (accuracy ±1 mm), which is defined as the vertical distance from the liquid surface to the top of the foam;

[0099] (4) Determination of half-life: Use a stopwatch to time the foam and record the time t1 / 2 when the foam height decays to 0.5H0. Repeat the test three times and take the arithmetic mean.

[0100] 2. Viscosity test method: Brookfield rotational viscometer (25°C, rotor LV-4, speed 60 rpm);

[0101] The test results are shown in Table 2.

[0102] Table 2 Foam stability experimental data

[0103]

[0104] Comparing the foam stability half-lives of Comparative Examples 1 and 2 with Examples 1 to 5 shows that the presence of either tragacanth gum or xanthan gum alone improves foam stability to a certain extent, but this is far less effective than the combined presence of tragacanth gum and xanthan gum in the present invention. This is due to the lack of rheological regulation provided by xanthan gum in Comparative Example 1, which results in easy collapse of the foam structure. The lack of the three-dimensional network of tragacanth gum in Comparative Example 2, which results in a lack of foam support, demonstrates the synergistic effect of tragacanth gum and xanthan gum in the present invention. When tragacanth gum and xanthan gum are combined, they form a three-dimensional network through cross-linking of polysaccharide chains, significantly extending the foam lifespan (half-life ≥ 25.2 min) while balancing the dual effects of cleansing and skin feel.

[0105] When the mass ratio of tragacanth gum to xanthan gum is 5:1, and the thickener is composed of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum (i.e., Example 3), the synergistic effect is the strongest, with a half-life of 31.5 min. However, in Comparative Example 3, due to the large proportion of xanthan gum in the thickener (33%), the excessive xanthan gum destroys the foam network, resulting in a lower foam half-life. Comparative Example 5 shows that when the amount of xanthan gum added is low, the xanthan gum cannot play a good synergistic role, which reduces the foam performance. Comparative Examples 3 and 5 prove that the thickener in the present invention is a thickening system dominated by tragacanth gum, and when the mass ratio of tragacanth gum to xanthan gum in the system is outside 3:1-9:1, the effect of the present invention cannot be achieved.

[0106] Similarly, the initial foam heights in the present invention were all ≥138 mm, with the highest reaching 157 mm, indicating that the thickening system of tragacanth gum and xanthan gum can form dense foam. In Comparative Example 2, the lack of tragacanth gum resulted in low viscosity, loose foam, and an initial foam height of only 88 mm. In Comparative Example 4, the excessive amount of thickener resulted in an excessively high viscosity (11,500 cP) and a noticeable residual feel. In Examples 1-5, when the thickener was 1-2 parts by weight, the viscosity ranged from 7,600 to 10,400 cP, meeting the requirements for easy foaming and rinsing of facial cleansers.

[0107] Example 6

[0108] The present invention provides an amino acid moisturizing facial cleanser, which comprises the following raw materials in 100 parts by weight: 10 parts by weight of an amino acid surfactant, 13.45 parts by weight of a moisturizer, 1.8 parts by weight of a thickener, 0.1 parts by weight of a pH regulator, 0.1 parts by weight of a skin conditioner, 0.1 parts by weight of a fragrance, 0.01 parts by weight of a chelating agent, 0.1 parts by weight of a preservative, and the balance by weight of deionized water;

[0109] The pH regulator is lactic acid, the skin conditioning agent is a mixture of 0.05 parts of dipotassium glycyrrhizate and 0.05 parts of North American witch hazel extract, the fragrance is daily fragrance, the chelating agent is disodium EDTA, the preservative is parahydroxyacetophenone, the amino acid surfactant includes 50% by mass of potassium cocoyl glycinate (mass concentration is 40%) and 50% of sodium lauroyl sarcosinate (mass concentration is 25%), the thickener is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerin, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of tremella polysaccharide.

[0110] This embodiment also provides a method for preparing an amino acid moisturizing facial cleanser, comprising the following steps:

[0111] (1) Pre-dispersed tragacanth gum: pre-mix tragacanth gum and glycerol in proportion and shear disperse in 50°C water phase (speed 3000 rpm, time 10 minutes);

[0112] (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid;

[0113] (3) Heat the colloid to 65°C, add the amino acid surfactant, and stir until dissolved;

[0114] (4) Cool down to 35°C, add sodium hyaluronate, panthenol, Tremella polysaccharide in sequence, then add skin conditioner, fragrance, chelating agent, preservative, keep stirring at 30 rpm, and stir evenly;

[0115] (5) Adjust the pH to 5.5 with lactic acid;

[0116] (6) After homogenization at 12 MPa, the amino acid moisturizing facial cleanser was obtained by filling.

[0117] Example 7

[0118] The present invention provides an amino acid moisturizing facial cleanser, which comprises the following raw materials in 100 parts by weight: 20 parts by weight of an amino acid surfactant, 13.45 parts by weight of a moisturizer, 1.8 parts by weight of a thickener, 0.5 parts by weight of a pH regulator, 4 parts by weight of a skin conditioner, 0.5 parts by weight of a fragrance, 0.1 parts by weight of a chelating agent, 1 part by weight of a preservative, and the balance being deionized water;

[0119] The pH regulator is lactic acid, the skin conditioning agent is a mixture of 1 part dipropylene glycol, 1 part dipotassium glycyrrhizate and 2 parts of North American witch hazel extract, the fragrance is daily use essence, the chelating agent is disodium EDTA, the preservative is parahydroxyacetophenone, the amino acid surfactant includes 60% by mass of potassium cocoyl glycinate (mass concentration is 40%) and 40% of sodium lauroyl sarcosinate (mass concentration is 25%), the thickener is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerin, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of tremella polysaccharide.

[0120] This embodiment also provides a method for preparing an amino acid moisturizing facial cleanser, comprising the following steps:

[0121] (1) Pre-dispersed tragacanth gum: pre-mix tragacanth gum and glycerol in proportion and shear disperse in a 60°C aqueous phase (speed 5000 rpm, time 15 minutes);

[0122] (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid;

[0123] (3) Heat the colloid to 80°C, add amino acid surfactant, and stir until dissolved;

[0124] (4) Cool down to 40°C, add sodium hyaluronate, panthenol, Tremella polysaccharide in sequence, then add skin conditioner, fragrance, chelating agent, preservative, keep stirring at 30 rpm, and stir evenly;

[0125] (5) Adjust the pH to 6.5 with lactic acid;

[0126] (6) After homogenization at 15 MPa, the amino acid moisturizing facial cleanser was obtained by filling.

[0127] Example 8-Example 12 and Comparative Example 6-Comparative Example 10

[0128] The present invention provides an amino acid moisturizing facial cleanser, wherein the total weight parts are 100 parts. Compared with Example 3, the ratio of the thickener, the ratio of the moisturizing agent, and the weight parts of deionized water in Examples 8 to 12 and Comparative Examples 6 and 10 are different. The thickener and moisturizing agent in Examples 8 to 12 and Comparative Examples 6 and 10 are selected as follows:

[0129] Example 8

[0130] In this embodiment, the thickener is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerin, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of Tremella polysaccharide.

[0131] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0132] Example 9

[0133] In this embodiment, the thickener is a mixture of 1.7 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 8 parts by weight of glycerin, 1 part by weight of sodium hyaluronate, 4 parts by weight of panthenol, and 0.7 parts by weight of Tremella polysaccharide.

[0134] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0135] Example 10

[0136] In this embodiment, the thickener is a mixture of 1 part by weight of tragacanth gum and 0.3 part by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 5 parts by weight of glycerin, 0.5 parts by weight of sodium hyaluronate, 2 parts by weight of panthenol, and 0.3 parts by weight of Tremella polysaccharide.

[0137] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0138] Example 11

[0139] In this embodiment, the thickener is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerol, 3 parts by weight of panthenol, and 0.5 parts by weight of Tremella polysaccharide.

[0140] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0141] Example 12

[0142] In this embodiment, the thickener is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of Tremella polysaccharide.

[0143] Based on the raw material composition and weight parts of this embodiment, this embodiment prepares the amino acid moisturizing facial cleanser according to the steps of Example 1.

[0144] Comparative Example 6

[0145] The thickener in this comparative example is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of urea, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of tremella polysaccharide.

[0146] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that urea was used instead of glycerol in step (1).

[0147] Comparative Example 7

[0148] The thickener of this comparative example is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the humectant is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerol, 0.75 parts by weight of trehalose, 3 parts by weight of panthenol, and 0.5 parts by weight of tremella polysaccharide.

[0149] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that trehalose was used instead of sodium hyaluronate in step (3).

[0150] Comparative Example 8

[0151] The thickener in this comparative example is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerin, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of propylene glycol, and 0.5 parts by weight of tremella polysaccharide.

[0152] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that propylene glycol was used instead of panthenol in step (3).

[0153] Comparative Example 9

[0154] The thickener in this comparative example is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the moisturizer is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of glycerin, 0.75 parts by weight of sodium hyaluronate, 3 parts by weight of panthenol, and 0.5 parts by weight of xylitol.

[0155] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that xylitol was used instead of the Tremella polysaccharide in step (3).

[0156] Comparative Example 10

[0157] The thickener of this comparative example is a mixture of 1.5 parts by weight of tragacanth gum and 0.3 parts by weight of xanthan gum, and the humectant is a mixture of 3.2 parts by weight of 1,2-ethylene glycol, 6 parts by weight of urea, 0.75 parts by weight of trehalose, 3 parts by weight of propylene glycol, and 0.5 parts by weight of xylitol.

[0158] Based on the raw material composition and weight parts of this comparative example, an amino acid moisturizing facial cleanser was prepared according to the steps of Example 1, except that urea was used instead of glycerol in step (1), and trehalose, propylene glycol, and xylitol were used instead of other moisturizing agents in step (3).

[0159] Performance test of amino acid moisturizing facial cleansers prepared in Examples 6 to 12 and Comparative Examples 6 to 10

[0160] 1. 1-hour moisturizing improvement rate (%)

[0161] Test method:

[0162] Instruments and standards: Use skin moisture testers that comply with ISO 24442:2011 (such as Corneometer ® CM825), calibrated to a standard environment (temperature 20±1°C, relative humidity 50±5%).

[0163] Test conditions: 120 healthy adults, including women aged 18-45, were randomly divided into 12 groups, with 10 participants in each group. Before testing, the participants were placed in a constant temperature and humidity environment for 30 minutes. The test area on the inner forearm (avoiding the injured area) was cleaned and dried.

[0164] Test samples: amino acid moisturizing facial cleansers prepared in Examples 6 to 12 and Comparative Examples 6 to 10;

[0165] Test steps:

[0166] Measure the basic moisture value (M0) of the untreated area;

[0167] Apply the test sample (0.1 g / cm²) evenly, massage for 1 minute (pressure 0.2 N / cm²), rinse with 37°C deionized water, and pat dry with a soft towel.

[0168] The subjects remained seated, and the moisture value of the treated area (M1) was measured 1 hour later.

[0169] Calculation formula:

[0170] 1 hour moisturizing improvement rate (%) = (M1-M0) / M0×100%

[0171] Evaluation criteria: A retention rate of ≥15% is considered to have a long-lasting moisturizing effect (refer to the "Guidelines for the Evaluation of Moisturizing Efficacy of Cosmetics" QB / T 4256-2011)

[0172] 2. 4-hour moisturizing retention rate (%)

[0173] Test method:

[0174] Continuation test: After completing the 1-hour moisturizing improvement rate test, continue to maintain the above subjects in a standard environment, and prohibit contact with water or other intervention measures;

[0175] Data collection: Measure the moisture value (M4) of the same treatment area 4 hours after applying the facial cleanser;

[0176] Calculation formula: 4-hour moisturizing retention rate (%) = (M4-M0) / M0×100%

[0177] Evaluation criteria: A retention rate ≥15% is considered to have a long-lasting moisturizing effect (refer to the "Guidelines for the Evaluation of Moisturizing Efficacy of Cosmetics" QB / T 4256-2011).

[0178] 3. TEWL (transepidermal water loss) reduction rate (%)

[0179] Test method:

[0180] Instruments and standards: Use Tewameter certified to ISO 24444:2019 ® TM300 probe, measuring the rate of water loss from the stratum corneum.

[0181] Test steps:

[0182] Measure the basal TEWL value (T0) of the untreated area;

[0183] 24 hours after application of the samples (amino acid moisturizing facial cleansers prepared in Examples 6-12 and Comparative Examples 6-10) (simulating the barrier recovery period after a single use), the TEWL value (T1) of the same area was measured;

[0184] Calculation formula:

[0185] TEWL reduction rate (%) = (T0-T1) / T0×100

[0186] Effectiveness determination: TEWL reduction rate ≥ 10% indicates that the product has significant barrier repair function (based on Dermatology reference threshold)

[0187] The test results are shown in Table 3

[0188] Table 3 Moisturizing test data

[0189]

[0190] As shown in Table 3, the amino acid moisturizing facial cleanser of the present invention exhibits excellent moisturizing properties and skin barrier repair, achieving a 1-hour moisturizing improvement (%) of 18.9 ± 1.8 or greater, a 4-hour moisturizing retention rate (%) of 61.3 ± 2.7 or greater, and a TEWL reduction rate of 20.1 ± 1.3 or greater. The best results were achieved when the moisturizer simultaneously contained glycerin, sodium hyaluronate, panthenol, and Tremella fuciformis polysaccharide, achieving a 1-hour moisturizing improvement (%) of 27.8 ± 1.9 or greater, a 4-hour moisturizing retention rate (%) of 76.5 ± 2.8 or greater, and a TEWL reduction rate of 30.5 ± 1.7 or greater. Compared with Example 8, the moisturizing performance of Comparative Examples 6 to 10 is greatly reduced, which indicates that small molecule hydrating agents such as urea and trehalose destroy the integrity of the tragacanth gum network due to steric hindrance or hydrogen bond competition effects, resulting in a significant decrease in moisturizing performance, a decrease in moisturizing retention rate of >30%, and a TEWL reduction effect of less than 50% of that in Example 6. This proves that in the present invention, under the premise of the three-dimensional network structure of tragacanth gum, a synergistic effect is produced with the various substances in the moisturizer to form a stable "network-small molecule" composite system.

[0191] In summary, the glycerin, sodium hyaluronate, panthenol, and Tremella polysaccharide in the present invention can form a hydrogen bond-network synergistic system with tragacanth gum, achieving integrated moisturizing of "moisture absorption-water lock-repair", which can significantly improve the mildness and long-lasting moisturizing performance of amino acid facial cleansers, and is especially suitable for sensitive skin, dry skin and barrier-damaged skin care products.

[0192] It should be understood that the purpose of these embodiments is only to illustrate the present invention and is not intended to limit the scope of protection of the present invention. In addition, it should also be understood that after reading the technical content of the present invention, those skilled in the art may make various changes, modifications and / or variations to the present invention, and all of these equivalent forms also fall within the scope of protection defined by the claims appended hereto.

Claims

1. An amino acid moisturizing facial cleanser, characterized in that: The invention comprises the following raw materials in parts by weight: 10-30 parts of amino acid surfactant, 7.4-17 parts of moisturizing agent, 1-2 parts of thickener, 0.1-4 parts of skin conditioning agent, 0.1-0.5 parts of pH adjusting agent, 0.1-0.5 parts of fragrance, 0.1-1 parts of preservative, 0.01-0.1 parts of chelating agent and 49-82 parts of deionized water; The thickener comprises tragacanth gum and xanthan gum, and the mass ratio of the tragacanth gum to the xanthan gum is (3:1)-(9:1); The moisturizing agent includes at least two of glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and tremella polysaccharide.

2. An amino acid moisturizing facial cleanser according to claim 1, characterized in that, The moisturizing agent includes glycerin, 1,2-ethylene glycol, sodium hyaluronate, panthenol, and Tremella polysaccharide; In the amino acid moisturizing facial cleanser, the amount of 1,2-ethylene glycol is 3.2 parts by weight, and the weight ratio of tragacanth gum, glycerin, sodium hyaluronate, panthenol, and tremella polysaccharide is (1-1.7):(5-8):(0.5-1):(2-4):(0.3-0.7).

3. The amino acid moisturizing facial cleanser according to claim 1, characterized in that: The amino acid surfactant is selected from at least two of sodium cocoyl glycinate, potassium cocoyl glycinate, disodium cocoyl glutamate, sodium lauroyl glutamate and sodium lauroyl sarcosinate.

4. The amino acid moisturizing facial cleanser according to claim 1, characterized in that: The preservative is selected from one of phenoxyethanol, caprylhydroxamic acid, and p-hydroxyacetophenone; The chelating agent is disodium EDTA; The fragrance is a daily fragrance.

5. The amino acid moisturizing facial cleanser according to claim 1, characterized in that: The pH adjuster is selected from lactic acid or citric acid.

6. The amino acid moisturizing facial cleanser according to claim 1, characterized in that: The skin conditioning agent is selected from at least two of dipotassium glycyrrhizate, witch hazel extract, and dipropylene glycol.

7. A method for preparing the amino acid moisturizing facial cleanser according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) Premix tragacanth gum and glycerin in proportion, and shear disperse in a 50-60°C aqueous phase at a speed of 3000-5000 rpm for 10-15 minutes; (2) Add xanthan gum and stir until it is completely swollen and forms a uniform colloid; (3) Heat the colloid to 65-80°C, add amino acid surfactant, and stir until dissolved; (4) Cool down to 35-40℃, add moisturizer first, then add skin conditioner, fragrance, chelating agent, preservative and mix well; (5) Adjust the pH to 5.5-6.5 with a pH regulator; (6) At a pressure of 10-15 MPa, the amino acid moisturizing facial cleanser is obtained by homogenizing and filling.

Images