Three-layer essence suitable for dry skin as well as preparation method and application of three-layer essence

Abstract

The invention discloses a three-layer essence suitable for dry skin and a preparation method and application thereof.The three-layer essence comprises an oil layer, a water layer and an emulsifier layer between the oil layer and the water layer, the oil layer comprises non-polar grease with the polarity index being 0-1.5 and polar grease with the polarity index being 1.5-5.0, and the osmotic pressure of the water layer is larger than or equal to 60 mOsm / L; the mass ratio of the polar grease to the non-polar grease is (1: 1.7)-(1: 7), and the emulsifier layer accounts for 0.015-0.06% of the total mass. The preparation method comprises the following steps: dissolving the emulsifier in the polar grease, and mixing with the water phase and the non-polar grease to form the three-layer essence. The three-layer essence integrally comprises three layers which are clear, transparent and clear in interface, is novel in appearance, can be emulsified only by slight shaking during use, is small in emulsion liquid drop and moderate in emulsified state keeping time, the preparation method is simple and easy to operate, and conventional components in the field of cosmetics can be added into a water layer and an oil layer respectively according to requirements. Repairing functions with different functions can be achieved, and the application scene is wide.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of skin care, in particular to a three-layer essence suitable for dry skin and a preparation method and application thereof. BACKGROUND

[0002] Dry skin lacks sufficient moisture and oil, and the water content in the stratum corneum is usually less than 10% (the water content in the stratum corneum of normal skin is 15% to 25%), thus a series of problems will occur: the skin often feels dry and tight, especially after cleansing or in a dry environment, research shows that more than 80% of dry skin people will have obvious tightness within 10 minutes after cleansing; the lack of moisture and oil makes the skin elasticity decrease and the collagen loss accelerate, and fine lines and wrinkles are prone to occur in the expression-rich areas such as the corners of the eyes, mouth and forehead, clinical data shows that the probability of wrinkles in dry skin people over 30 years old is about 40% higher than that in neutral skin people, and the wrinkles gradually deepen with age.

[0003] In order to let the skin return to a healthy state, deep nutrition repair is needed for the skin, and using essence is one of the feasible methods. The common dosage forms of essence include water type, oil type and water-oil type, among which, the water-oil type is particularly suitable for dry skin with damaged water-oil balance.

[0004] Most of the essence products on the market are single-layer systems in the form of water, emulsion and oil, however, pure water-soluble ingredients or oil-soluble ingredients cannot well solve the problem of moisturizing dry skin. In addition, the greasy skin feeling of oil single-layer system makes many even dry skin users step back. Although the water product is refreshing, the moisturizing power is not enough.

[0005] To solve this problem, more and more water-oil double-layer products appear, balancing the skin feel while retaining the advantages of moisturizing. Chinese patent CN105147528A discloses a double-layer essence with moisturizing effect and its preparation method and application. The essence is prepared from 3%-8% caprylic / capric triglyceride, 3%-6% jojoba oil, 5%-15% glycerol, etc. oil, water-soluble raw materials and water raw materials. The prepared essence is a double-layer stable system, has a new and different visual effect, and can achieve rapid layering in about 48 hours, completely separating into two layers. Chinese patent CN105147528A discloses a water-oil double-layer essence, which is composed of cyclopentasiloxane, acacia, isododecane, pentaerythritol tetra(ethylhexanoate), butanediol, propylene glycol, glycerol polyether-26, glycerol, water and other raw materials. The prepared water-oil double-layer essence has a novel and beautiful appearance, can achieve rapid layering, has stable emulsion properties and good moisturizing performance. CN116999373A discloses a water-oil double-layer essence, which is composed of cyclopentasiloxane, acacia, isododecane, pentaerythritol tetra(ethylhexanoate), butanediol, propylene glycol, glycerol polyether-26, glycerol, water and other raw materials. The prepared water-oil double-layer essence has a novel and beautiful appearance, can achieve rapid layering, has stable emulsion properties and good moisturizing performance.

[0006] Further, water-oil three-layer products or technologies appear on the market. Chinese patent CN111759746A discloses a three-layer essence with moisturizing and whitening dual effects and its preparation method. The raw materials of the three-layer essence include glycerol, hydroxyethyl cellulose, sodium hyaluronate, trehalose, betaine, nicotinamide, Tween 20, isohexadecane, isononyl isononanoate, dimethicone, cetylstearyl alcohol, sodium chloride, yeast extract, vitamin C ethyl ether, preservative and water. This invention creates a novel appearance effect of oil: milk: water three layers by adjusting the amount ratio of emulsifier Tween 20 and three kinds of oils. Chinese patent CN115024987A discloses a three-layer essence with repair and moisturizing effects, which includes a bottom water phase layer, a middle oil phase layer and a top oil phase layer. The bottom water phase layer uses water as the main solvent, the middle oil phase layer uses castor (RICINUS COMMUNIS) seed oil as the main solvent, and the top oil phase layer uses a combination of C15-19 alkyl and C9-12 alkyl as the main solvent. Due to the unique incompatibility of castor (RICINUS COMMUNIS) seed oil, the essence provided by this invention has a relatively unique three-layer system.

[0007] The essence preparation method disclosed in the above documents mainly uses the difference between oil and water and the difference in oil density to achieve the purpose of stratification, and obtain a multi-layer appearance. These products / technologies have the problems of water phase layer not being restored to a transparent state for a long time, or stratification being too fast, requiring multiple shaking and use, and inconvenience in use. In addition, these products / technologies also have a common problem that the oil phase and the water phase are mixed only by collision between the two phases when used, and cannot form uniform emulsified droplets. When used, it is only a simple mixture of water and oil, which is a mixture of "oil flowers" and water, and has poor skin feel and low penetration and absorption rate. SUMMARY

[0008] The technical problem to be solved by the present application is to provide a three-layer essence suitable for dry skin and a preparation method and application thereof, wherein the three-layer essence is clear and transparent, and the interface is clear, and can form an emulsion when slightly shaken, the droplets are small, the maintenance time is moderate, the preparation method is simple and easy to operate, and the three-layer essence is suitable for preparing skin care products.

[0009] To solve the above technical problems, the first aspect of the present application provides a three-layer essence suitable for dry skin, which comprises an oil layer, a water layer, and an emulsifier layer between the oil layer and the water layer, wherein the oil layer comprises non-polar oil with a polarity index of 0-1.5 and polar oil with a polarity index of 1.5-5.0, and the osmotic pressure of the water layer is ≥60 mOsm / L.

[0010] The mass ratio of polar oil to non-polar oil is 1:1.7-1:7, and the emulsifier layer accounts for 0.015%-0.06% of the total mass.

[0011] The three-layer essence provided by the present application, in a normal state, comprises an oil layer, a water layer, and an emulsifier layer between the oil layer and the water layer, the stratification is clear, and due to the small amount of emulsifier, the emulsifier layer is transparent in the form of droplets between the oil layer and the water layer, the droplets can be in a continuous phase or dispersed state, the whole is clear and transparent, the interface is clear, and the appearance is novel; when used, the oil layer and the water layer form oil-in-water emulsion droplets with a diameter of about 5-50 microns under the action of the emulsifier layer, i.e. uniform emulsion, to improve the penetration of active substances in the skin, improve the utilization of active substances, and maintain the emulsified state for at least 5 min to meet the user's use requirements, and can be restored to the clear stratification state of the oil layer-emulsifier layer-water layer after 8 h, and the diameter of the emulsion droplets is in the range of 5-50 μm, which is suitable for skin absorption; the three-layer essence suitable for dry skin provided by the present application can add conventional ingredients in the cosmetic field to the water layer and the oil layer according to the needs, and can realize different repair functions, and has a wide application scenario.

[0012] In the present application, the principle of forming a three-layer visual effect is that, in the presence of a water layer with a certain osmotic pressure, the emulsifier dissolved in the polar oil is precipitated and is between the water layer and the oil layer. Based on this, the osmotic pressure of the water layer plays an important role in the precipitation of the emulsifier, and the osmotic pressure is not less than 60 mOsm / L. When the osmotic pressure of the water layer is too low, not only the emulsifier cannot be precipitated from the oil layer, but also the emulsifier and part of the oil and the water phase are emulsified to form a thick emulsion layer, thereby forming a three-layer structure of an upper oil layer, a middle emulsion layer and a lower water layer, and the middle emulsion layer is difficult to be demulsified. At the same time, since the emulsifier is insoluble in non-polar oil, the mass ratio of polar oil to non-polar oil in the oil layer also plays an important role in the precipitation of the emulsifier. When the mass ratio of polar oil in the oil layer is too high, even if the water layer has an osmotic pressure higher than 60 mOsm / L, the emulsifier is difficult to precipitate, which leads to the difficulty in forming a three-layer visual effect, and even after shaking several times, the system cannot form emulsion droplets, that is, the emulsifier cannot play an emulsifying effect. When the mass ratio of polar oil in the oil layer is too low, although a clear three-layer visual effect can be formed, after shaking to form emulsion droplets, the emulsion cannot be broken for a long time (at least 48 h), that is, after use, the essence liquid is in an emulsified state for a long time, rather than a three-layer visual effect. The three-layer essence provided by the present application maintains a three-layer state within the daily temperature range; when the container is filled, at least 5% of the space is preferably reserved for shaking before use to produce an emulsifying effect.

[0013] In a specific manner, the mass ratio of the oil layer to the water layer is 1:0.4-1:7. In this specific embodiment, if the water layer accounts for too large a proportion, it is easy to cause the emulsion droplets to be too large after shaking, the moisturizing degree is not enough, the absorption is slow, and it is also easy to quickly demulsify and not meet the user's time requirements; if the water layer accounts for too small a proportion, it is easy to cause the skin to feel greasy, the absorption is slow, and it is also easy to quickly demulsify and affect use.

[0014] In a specific manner, the polar oil includes one or more of coconut oil alcohol-octanoate / decanoate, isopropyl stearate, caprylic / capric triglyceride, jojoba seed oil, sunflower seed oil, avocado oil, oil olive fruit oil, castor seed oil, PPG-15 stearyl alcohol ether; the non-polar oil includes one or more of C9-12 alkane, C13-14 alkane, C13-15 alkane, C15-19 alkane, C15-23 alkane, C18-21 alkane, C10-11 isoparaffin, C10-12 isoparaffin, C10-13 isoparaffin, C12-14 isoparaffin, C13-14 isoparaffin, C13-16 isoparaffin, mineral oil, squalane.

[0015] In a specific embodiment, the water layer comprises water and solutes dissolved in the water, wherein the solutes comprise one or more of humectants, antioxidants, skin conditioning agents, pH adjusting agents, anti-wrinkle agents, tonicity adjusting agents, preservatives, thickening agents. Preferably, the water layer has an osmotic pressure of 310-700 mOsm / L (Note that the osmotic pressure of the water layer is related to the solutes in the water. When the solutes in the water are non-dissociated solutes, the osmotic pressure of a 1 mmol / L aqueous solution thereof is about 1 mOsm / L; when the solutes in the water are dissociated solutes, the osmotic pressure of a 1 mmol / L aqueous solution thereof is about 2 mOsm / L). Understandably, the solutes can be selected according to the functional requirements, and conventional water-soluble humectants, solvents, antioxidants, skin conditioning agents, pH adjusting agents, anti-wrinkle agents, tonicity adjusting agents, preservatives, thickening agents, etc. in the prior art are all suitable for use in the present application. In addition, bacteriostatic agents, etc. can also be added to the water layer of the present application. In addition, the osmotic pressure of the water layer should not be too high. If it is higher than 700 mOsm / L, it can irritate the skin, especially the barrier-damaged sensitive skin. Preferably, the osmotic pressure is controlled to be between 310-700 mOsm / L, i.e. slightly higher than the skin cells and intercellular matrix, so that the solution can diffuse through the semi-permeable membrane from the high concentration to the low concentration to occur osmosis, thereby making the functional substances easy to be absorbed by the skin.

[0016] In a specific embodiment, the emulsifier layer comprises an emulsifier, which can be dissolved in the polar oil and is insoluble in the non-polar solvent at 0-40℃; the mass ratio of the emulsifier to the polar oil is not less than 1:40. Preferably, the emulsifier is a glycolipid and / or a complex formed by PEG-20 glyceryl triisostearate and polyglyceryl-2 sesqui caprylate, wherein the mass ratio of PEG-20 glyceryl triisostearate to polyglyceryl-2 sesqui caprylate in the complex is 1:4-4:1.

[0017] In this specific embodiment, the emulsifier layer is the emulsifier separated from the polar oil, and since the emulsifier is dissolved in the polar oil, it is a polar molecule and thus generally insoluble in the non-polar solvent. In addition, when the mass ratio of the emulsifier to the polar oil is less than 1:40, the emulsifier is slowly dissolved, which is not conducive to production, and the product is not easy to emulsify.

[0018] To solve the above technical problems, the second aspect of the present application provides a use of the aforementioned three-layer serum suitable for dry skin in the preparation of skin care products. The skin care products can be, for example, moisturizing serum, repair serum, soothing serum, firming serum, whitening serum, anti-aging serum, etc. According to the functional requirements, the relevant ingredients in the prior art can be added to the water layer and / or the oil layer. Understandably, the skin care products prepared by using the aforementioned three-layer serum suitable for dry skin have at least all the technical effects of the three-layer serum.

[0019] To solve the above technical problems, a second aspect of the present application provides a preparation method of a three-layer essence suitable for dry skin, characterized in that it comprises the following steps:

[0020] S1, preparing an aqueous phase with an osmotic pressure not less than 60 mOsm / L;

[0021] S2, dissolving an emulsifier in a polar oil with a polar index of 1.5-5.0;

[0022] S3, mixing the aqueous phase of step S1, the polar oil with the dissolved emulsifier of step S2, and a non-polar oil phase with a polar index of 0-1.5, and after standing, the aqueous phase forms a water layer, the oil phase forms an oil layer, the emulsifier separates from the polar oil to form an emulsifier layer, and the emulsifier layer is located between the water layer and the oil layer, i.e., a three-layer essence is obtained; wherein the mass ratio of the polar oil and the non-polar oil is 1:1.7-1:7, and the emulsifier layer accounts for 0.015%-0.06% of the total mass.

[0023] In the preparation method of the three-layer essence suitable for dry skin provided by the present application, the amount of emulsifier added is very low, and the viscosity is large, which makes it difficult to add separately in the subsequent packaging process. Therefore, before packaging, the emulsifier needs to be dissolved in the oil phase to form a uniform mixed system to ensure the certainty of the amount added during packaging. However, the emulsifier in the present application is not soluble in the mixture formed by the polar oil and the non-polar oil at room temperature. Although the emulsifier can be dissolved in the mixture after heating to 60℃, the emulsifier will still separate out when the temperature decreases, which will still cause the content of emulsifier to be unstable after packaging, ultimately resulting in unstable product quality. Based on this, in the present application, the emulsifier is first dissolved in the polar oil to form a uniform system, and then it is filled into a container with the aqueous phase and the non-polar oil, respectively, thereby ensuring the product quality. The preparation method of the present application is simple to operate, facilitates material mixing, especially facilitates the addition of emulsifier, and is suitable for industrial application.

[0024] It should be noted that the three-layer essence obtained by the method provided by the present application is prepared by mixing polar oil and non-polar oil with an emulsifier, and the water layer is directly formed; in the static process, the emulsifier is separated from the oil layer under the osmotic pressure of the water layer; in the normal state, the interfaces between the oil layer, the water layer and the emulsifier layer are clear, and when the emulsifier is between the oil layer and the water layer, the emulsifier layer presents a transparent droplet shape, and the droplets between the emulsifier layer present a continuous phase or a dispersed state, which is novel in appearance. When used, the essence is slightly shaken (one hand holds the container, the arm naturally droops, and the wrist is slightly shaken) for 2-10 seconds, the shaking frequency is 1-3 times per second, and under the action of the emulsifier layer, the oil layer and the water layer form oil-in-water emulsion droplets with a diameter of about 5-50 microns, that is, a uniform emulsion, so as to improve the penetration of the active substance in the skin and the utilization of the active substance, and the emulsion state is maintained for at least 5 minutes to meet the use requirements of the user, and the emulsion droplets can restore to the oil layer-emulsifier layer-water layer cleaning layered state after 8 hours, and the diameter of the emulsion droplets is in the range of 5-50 microns, which is suitable for skin absorption; the present application can also add conventional ingredients in the cosmetic field according to the requirements during the preparation of each phase, and then encapsulate (mix) to make the obtained three-layer essence suitable for different scenes.

[0025] In a specific scheme, in step S1, the water phase comprises water and a solute dissolved in water, wherein the solute comprises one or more of a humectant, an antioxidant, a skin conditioner, a pH adjuster, an anti-wrinkle agent, an osmotic pressure regulator, a preservative, and a thickening agent. Preferably, the osmotic pressure of the water phase is 310 mOsm / L-700 mOsm / L.

[0026] In a specific scheme, in step S2, the polar oil comprises one or more of coco-caprylate / caprate, isopropyl stearate, caprylic / capric triglyceride, jojoba seed oil, sunflower seed oil, avocado oil, olive fruit oil, castor seed oil, and PPG-15 stearyl ether.

[0027] In a specific scheme, in step S3, the non-polar oil comprises one or more of C9-12 alkane, C13-14 alkane, C13-15 alkane, C15-19 alkane, C15-23 alkane, C18-21 alkane, C10-11 isoparaffin, C10-12 isoparaffin, C10-13 isoparaffin, C12-14 isoparaffin, C13-14 isoparaffin, C13-16 isoparaffin, mineral oil, and squalane.

[0028] The mass ratio of the oil phase to the water phase is 1:0.4-1:7.

[0029] In a specific solution, the mass ratio of the emulsifier to the polar oil is not less than 1:40; the emulsifier is not dissolved in the non-polar solvent at 0-40℃. Preferably, the emulsifier is a sugar lipid and / or a complex formed by PEG-20 glyceryl triisostearate and polyglyceryl-2 sesqui caprylate, wherein the mass ratio of PEG-20 glyceryl triisostearate to polyglyceryl-2 sesqui caprylate in the complex is 1:4-4:1. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the present application, the following briefly introduces the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort based on these drawings.

[0031] Figure 1A The state photo of the prepared essence of Example 1 after standing for 24h;

[0032] Figure 1B The emulsion state photo of the prepared essence of Example 1 after shaking for 3 times;

[0033] Figure 1C The state photo of the prepared essence of Example 1 after standing for 8h after shaking;

[0034] Figure 2 The state photo of the prepared essence of Comparative Example 1 after standing for 24h;

[0035] Figure 3 The state photo of the prepared essence of Comparative Example 4 after standing for 24h. DETAILED DESCRIPTION

[0036] The technical solutions in the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.

[0037] Example 1

[0038] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0039] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of sugar lipid were mixed and heated in a water bath at 60℃, and stirred until dissolved, and then cooled to room temperature;

[0040] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0041] In a 120 mL container, 5.03 g of the polar oil with dissolved emulsifier of step S2, 17.5 g of the non-polar oil, and water phase are filled respectively, sealed after filling to 100 g, and left to stand for 24 h. The emulsifier is precipitated to form an upper oil layer, a lower water layer, and a middle emulsifier layer which is clear and transparent and has a clear interface. Figure 1A

[0042] The three-layer essence liquid obtained in this example is taken, a container is held with one hand, the arm is naturally lowered, and the wrist is slightly shaken several times (such as 3 times in 2 s). The emulsion is in a state as shown in Figure 1B After 5 minutes, the emulsion state is restored, and the three-layer essence liquid is clear and transparent and has a clear interface after about 8 h, as shown in Figure 1C

[0043] Example Two

[0044] S1, 2.0 parts by mass of sodium chloride and 98.0 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0045] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid are mixed, heated in a 60°C water bath, and stirred to be dissolved, and then cooled to room temperature;

[0046] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0047] In a 120 mL container, 5.03 g of the polar oil with dissolved emulsifier of step S2, 17.5 g of the non-polar oil, and water phase are filled respectively, sealed after filling to 100 g, and left to stand for 24 h. The emulsifier is precipitated to form an upper oil layer, a lower water layer, and a middle emulsifier layer which is clear and transparent and has a clear interface.

[0048] In this example, the osmotic pressure of the water phase in step S1 is changed compared with example one.

[0049] Example Three

[0050] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0051] S2, 8.18 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid are mixed, heated in a 60°C water bath, and stirred to be dissolved, and then cooled to room temperature; ​​

[0052] S3, 5.73 parts by mass of squalane and 8.59 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0053] In a 120 mL container, 8.21 g of the polar oil in which the emulsifier is dissolved in step S2, 14.32 g of the non-polar oil, and the water phase are respectively filled, sealed after filling to 100 g, and left to stand for 24 h, and the emulsifier is precipitated to form an upper oil layer, a lower water layer, and a middle emulsifier layer which is clear and transparent and has a clear interface.

[0054] In this example, the mass ratio of the polar oil to the non-polar oil is changed to 1:1.75 compared with example one.

[0055] Example Four

[0056] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0057] S2, 2.81 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid are mixed and heated in a 60°C water bath, stirred to be dissolved, and cooled to room temperature;

[0058] S3, 7.88 parts by mass of squalane and 11.81 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0059] In a 120 mL container, 2.84 g of the polar oil in which the emulsifier is dissolved in step S2, 19.69 g of the non-polar oil, and the water phase are respectively filled, sealed after filling to 100 g, and left to stand for 24 h, and the emulsifier is precipitated to form an upper oil layer, a lower water layer, and a middle emulsifier layer which is clear and transparent and has a clear interface.

[0060] In this example, the mass ratio of the polar oil to the non-polar oil is changed to 1:7 compared with example one.

[0061] Example Five

[0062] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0063] S2, 2.87 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid are mixed and heated in a 60°C water bath, stirred to be dissolved, and cooled to room temperature;

[0064] S3, 4.02 parts by mass of squalane and 6.02 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0065] In a 120 mL container, respectively fill 2.9 g of the polar oil and fat with dissolved emulsifier of step S2, 10.04 g of non-polar oil and fat, and then fill the water phase to 100 g, seal, stand for 24 h, and then the emulsifier is precipitated to form an upper oil layer, a lower water layer, and a clear and transparent middle emulsifier layer with clear interface.

[0066] In this example, the mass ratio of the oil layer and the water layer is changed to 1:6.74 (12.91:87.06) compared with example one.

[0067] Example six

[0068] S1, mix 1.0 part by mass of sodium chloride and 99.0 parts by mass of purified water, and stir until completely dissolved to obtain a water phase;

[0069] S2, mix 15.54 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid, heat in a 60°C water bath, and stir until dissolved, and then cool to room temperature;

[0070] S3, mix 21.76 parts by mass of squalane and 32.63 parts by mass of C15-19 alkane, and stir until uniform to form a non-polar oil and fat;

[0071] In a 120 mL container, respectively fill 15.57 g of the polar oil and fat with dissolved emulsifier of step S2, 54.39 g of non-polar oil and fat, and then fill the water phase to 100 g, seal, stand for 24 h, and then the emulsifier is precipitated to form an upper oil layer, a lower water layer, and a clear and transparent middle emulsifier layer with clear interface.

[0072] In this example, the mass ratio of the oil layer and the water layer is changed to 1:0.43 (69.93:30.04) compared with example one.

[0073] Example seven

[0074] S1, mix 1.0 part by mass of sodium chloride and 99.0 parts by mass of purified water, and stir until completely dissolved to obtain a water phase;

[0075] S2, mix 5 parts by mass of coco-caprylate / caprate and 0.015 parts by mass of glycolipid, heat in a 60°C water bath, and stir until dissolved, and then cool to room temperature;

[0076] S3, mix 7 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane, and stir until uniform to form a non-polar oil and fat;

[0077] In a 120 mL container, 5.015 g of polar oil and fat with dissolved emulsifier of step S2, 17.5 g of non-polar oil and fat, and water phase were respectively filled, sealed after filling to 100 g, and stood for 24 h. After standing, the emulsifier was precipitated, forming an upper oil layer, a lower water layer, and a clear and transparent middle layer of emulsifier.

[0078] In this example, the amount of glycolipid added was changed compared to example one.

[0079] Example Eight

[0080] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0081] S2, 5 parts by mass of coco-caprylate / caprate and 0.06 parts by mass of glycolipid were mixed and stirred until dissolved in a 60°C water bath, and then cooled to room temperature;

[0082] S3, 7 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil and fat;

[0083] In a 120 mL container, 5.06 g of polar oil and fat with dissolved emulsifier of step S2, 17.5 g of non-polar oil and fat, and water phase were respectively filled, sealed after filling to 100 g, and stood for 24 h. After standing, the emulsifier was precipitated, forming an upper oil layer, a lower water layer, and a clear and transparent middle layer of emulsifier.

[0084] In this example, the amount of glycolipid added was changed compared to example one.

[0085] Example Nine

[0086] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0087] S2, 5 parts by mass of coco-caprylate / caprate, and an emulsifier composed of 0.02 parts by mass of PEG-20 glyceryl triisostearate and 0.01 parts by mass of polyglyceryl-2 sesqui caprylate were mixed and stirred until dissolved, and then cooled to room temperature;

[0088] S3, 7 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil and fat;

[0089] In a 120 mL container, 5.03 g of polar oil and fat with dissolved emulsifier of step S2, 17.5 g of non-polar oil and fat, and water phase were respectively filled, sealed after filling to 100 g, and stood for 24 h. After standing, the emulsifier was precipitated, forming an upper oil layer, a lower water layer, and a clear and transparent middle layer of emulsifier.

[0090] In this example, the type of emulsifier added is changed relative to Example One.

[0091] Example Ten

[0092] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0093] S2, 5.0 parts by mass of caprylic / capric triglyceride and 0.03 parts by mass of glycolipid were mixed and heated in a water bath at 60°C, stirred until dissolved, and cooled to room temperature;

[0094] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil;

[0095] In a 120 mL container, 5.03 g of the polar oil in which the emulsifier was dissolved in step S2, 17.5 g of the non-polar oil, and the aqueous phase were filled in, sealed, and left to stand for 24 h, after which the emulsifier was precipitated to form an upper oil layer, a lower water layer, and a middle layer of the emulsion with a clear and transparent emulsifier and a clear interface.

[0096] In this example, the type of polar oil is changed relative to Example One.

[0097] Example Eleven

[0098] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0099] S2, 5.0 parts by mass of jojoba seed oil and 0.03 parts by mass of glycolipid were mixed and heated in a water bath at 60°C, stirred until dissolved, and cooled to room temperature;

[0100] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil;

[0101] In a 120 mL container, 5.03 g of the polar oil in which the emulsifier was dissolved in step S2, 17.5 g of the non-polar oil, and the aqueous phase were filled in, sealed, and left to stand for 24 h, after which the emulsifier was precipitated to form an upper oil layer, a lower water layer, and a middle layer of the emulsion with a clear and transparent emulsifier and a clear interface.

[0102] In this example, the type of polar oil is changed relative to Example One.

[0103] Example Twelve

[0104] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0105] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed, heated in a water bath at 60°C, stirred until dissolved, and cooled to room temperature;

[0106] S3, 17.5 parts by mass of squalane was used as the non-polar oil;

[0107] In a 120 mL container, 5.03 g of the polar oil in which the emulsifier was dissolved in step S2, 17.5 g of the non-polar oil, and then the aqueous phase were filled to 100 g, and then sealed. After standing for 24 h, the emulsifier was precipitated, forming an upper oil layer, a lower water layer, and a middle layer of clear and transparent emulsion with a clear interface.

[0108] In this example, the type of non-polar oil was changed compared to Example One.

[0109] Example Thirteen

[0110] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0111] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed, heated in a water bath at 60°C, stirred until dissolved, and cooled to room temperature;

[0112] S3, 17.5 parts by mass of C15-19 alkane was used as the non-polar oil;

[0113] In a 120 mL container, 5.03 g of the polar oil in which the emulsifier was dissolved in step S2, 17.5 g of the non-polar oil, and then the aqueous phase were filled to 100 g, and then sealed. After standing for 24 h, the emulsifier was precipitated, forming an upper oil layer, a lower water layer, and a middle layer of clear and transparent emulsion with a clear interface.

[0114] In this example, the type of non-polar oil was changed compared to Example One.

[0115] Comparative Example One

[0116] S1, 100 parts by mass of purified water was used as the aqueous phase;

[0117] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed, heated in a water bath at 60°C, stirred until dissolved, and cooled to room temperature;

[0118] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form the non-polar oil;

[0119] In a 120 mL container, 5.03 g of polar oil with dissolved emulsifier in step S2, 17.5 g of non-polar oil, and then water phase to 100 g were filled respectively, sealed, and left to stand for 24 h, forming an upper oil layer, a lower water layer, and a thick emulsion layer between the two layers, which was caused by the emulsification of the emulsifier, part of the oil, and part of the water phase, and the three-layer interface was not clear, as shown in Figure 2 . .

[0120] In this comparative example, pure water was used as the water phase, and a water layer was formed. Due to the low osmotic pressure, the emulsifier could not be precipitated from the oil layer, and the emulsifier, part of the oil phase, and part of the water phase formed an intermediate emulsion layer, which was not easy to be demulsified.

[0121] Comparative Example 2

[0122] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain a water phase;

[0123] S2, 10.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed and heated in a 60°C water bath, and stirred until dissolved, and then cooled to room temperature;

[0124] S3, 3.0 parts by mass of squalane and 4.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil;

[0125] In a 120 mL container, 10.03 g of polar oil with dissolved emulsifier in step S2, 7.5 g of non-polar oil, and then water phase to 100 g were filled respectively, sealed, and left to stand for 24 h, and observed to be two layers.

[0126] In this comparative example, the mass ratio of polar oil to non-polar oil was changed to 1:0.75 compared to Example 1. Due to the high proportion of polar oil, the glycolipid was completely dissolved in the oil phase, and even in the presence of a water layer with a certain osmotic pressure, the glycolipid was difficult to precipitate, resulting in a two-layer structure, rather than the clear and transparent three-layer essence liquid with clear interface in the present application.

[0127] Comparative Example 3

[0128] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain a water phase;

[0129] S2, 1.17 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed and heated in a 60°C water bath, and stirred until dissolved, and then cooled to room temperature;

[0130] S3, 6.53 parts by mass of squalane and 9.8 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0131] In a 120 mL container, 1.2 g of the polar oil with emulsifier dissolved in step S2, 16.33 g of the non-polar oil, and water phase are respectively filled, sealed after filling to 100 g, and left to stand for 24 h. A clear and transparent three-layer state with clear interface is presented. However, due to the low content of the polar oil, after shaking, it cannot be restored to the clear and transparent three-layer state with clear interface for a long time.

[0132] In this comparative example, the mass ratio of the polar oil to the non-polar oil is changed to 1:14 compared with Example 1.

[0133] Comparative Example 4

[0134] S1, 1 part by mass of sodium chloride and 99 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0135] S2, 5.0 parts by mass of coco-caprylate / caprate and 0.1 parts by mass of glycolipid are mixed and heated in a 60°C water bath to be dissolved, and then cooled to room temperature;

[0136] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0137] In a 120 mL container, 5.1 g of the polar oil with emulsifier dissolved in step S2, 17.5 g of the non-polar oil, and water phase are respectively filled, sealed after filling to 100 g, and left to stand for 24 h. Although a three-layer state is also presented (as shown in Figure 3 ), the middle layer is an emulsified layer formed by the emulsifier, part of the oil phase, and part of the water phase, rather than an emulsified layer. After shaking, it also cannot be restored to the clear and transparent three-layer state with clear interface shown in Example 1.

[0138] In this comparative example, the amount of glycolipid is changed to 0.1% compared with Example 1.

[0139] Comparative Example 5

[0140] S1, 1 part by mass of sodium chloride and 99 parts by mass of purified water are mixed and stirred to be completely dissolved to obtain a water phase;

[0141] S2, 5.0 parts by mass of coco-caprylate / caprate are used as the polar oil;

[0142] S3, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane are mixed and stirred to be uniform to form a non-polar oil;

[0143] In a 120 mL container, 5 g of polar oil from step S2, 17.5 g of non-polar oil, and water phase were filled respectively, sealed after filling up to 100 g, and left to stand for 24 h to form a two-layer structure. Since it does not contain an emulsifier, it cannot be emulsified even by shaking, but is a water-oil mixed system.

[0144] In this comparative example, no sugar lipid was added relative to Example 1.

[0145] Comparative Example 6

[0146] S1, 1 part by mass of sodium chloride and 99 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0147] S2, 22.5 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of sugar lipid were mixed, heated in a 60°C water bath, and stirred until dissolved, and then cooled to room temperature;

[0148] S3, 22.53 g of polar oil from step S2 in which an emulsifier was dissolved was filled in a 120 mL container, and then the aqueous phase was filled up to 100 g after sealing, and left to stand for 24 h to form a two-layer structure. The emulsifier was completely dissolved in the oil layer and was not easily precipitated.

[0149] In this comparative example, the oil layer was only polar oil and did not contain non-polar oil relative to Example 1.

[0150] Comparative Example 7

[0151] S1, 1 part by mass of sodium chloride and 99 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0152] S2, 9.0 parts by mass of squalane, 13.5 parts by mass of C15-19 alkane, and 0.03 parts by mass of sugar lipid were mixed and stirred (since the sugar lipid cannot be dissolved in the non-polar oil, the sugar lipid is difficult to uniformly disperse in the mixed system).

[0153] In a 120 mL container, 22.53 g of the mixture from step S2 was filled, and then the aqueous phase was filled up to 100 g after sealing, and left to stand for 24 h to form a three-layer structure that was clear and transparent and had a clear interface. However, after shaking, it was not possible to restore the three-layer structure that was clear and transparent and had a clear interface for a long time.

[0154] In this comparative example, the oil layer was only non-polar oil and did not contain polar oil relative to Comparative Example 1.

[0155] Comparative Example 8

[0156] S1, 1.0 parts by mass of sodium chloride and 99.0 parts by mass of purified water were mixed and stirred until completely dissolved to obtain an aqueous phase;

[0157] S2, 0.03 g emulsifier was loaded into a 120 mL container, then the water phase was filled to 100 g, sealed, and left to stand for 24 h. The emulsifier was on the top of the water phase, and the three layers were not clear and transparent, and the interface was clear. Because of the lack of oil phase, shaking could not emulsify.

[0158] This example did not contain an oil layer, only a water layer and an emulsifier layer.

[0159] Example 9

[0160] S1, 5.0 parts by mass of coco-caprylate / caprate and 0.03 parts by mass of glycolipid were mixed, heated in a 60°C water bath, stirred until dissolved, and cooled to room temperature;

[0161] S2, 7.0 parts by mass of squalane and 10.5 parts by mass of C15-19 alkane were mixed and stirred until uniform to form a non-polar oil;

[0162] A 120 mL container was filled with 5.03 g of polar oil containing emulsifier from step S1 and 17.5 g of non-polar oil from step S2, and left to stand for 24 h. Only an emulsifier layer and an oil layer were formed, and no water layer was present, which could not achieve emulsification.

[0163] This example did not contain a water phase.

[0164] Example 10

[0165] S1, 1.0 g of sodium chloride and 99.0 g of purified water were mixed and stirred until completely dissolved to obtain a water phase;

[0166] S2, 5.0 g of coco-caprylate / caprate, 7.0 g of squalane, 10.5 g of C15-19 alkane, and 0.03 g of glycolipid were mixed, heated in a 60°C water bath, stirred until dissolved, and cooled to room temperature. It can be seen that glycolipid was precipitated;

[0167] S3, a 120 mL container was filled with 22.53 g of oil phase obtained from step S2, then the water phase was filled to 100 g, sealed, and left to stand for 24 h. An upper oil layer, a lower water layer, and a clear and transparent middle emulsifier layer were formed. The three-layer serum obtained in this example was taken, and the container was held in one hand with the arm naturally hanging down, and the wrist was shaken slightly for a few times (such as 3 times in 2 s) to obtain an emulsion with a state as shown in Figure 1B After 5 minutes, the emulsion state gradually recovered, and after about 8 h, it recovered to a clear and transparent three-layer serum with a clear interface.

[0168] Because the viscosity of glycolipid is large, it is not convenient to add alone, and it is easy to precipitate in the mixed oil phase of polar oil and non-polar oil, which is not convenient for controlling the amount of addition during subsequent packaging. Therefore, this method is not suitable for industrial application.

[0169] Test Example

[0170] 1. Appearance Test:

[0171] Test Condition: First, observe the state of the prepared sample after standing for 24 hours, including whether it is clear and transparent and has three layers, and whether the interface is clear. Then, shake the sample three times (within 2 seconds) and observe the emulsification. After 5 minutes, observe whether the emulsification is maintained. After 8 hours, observe whether the sample can return to a state with clear and transparent three layers and a clear interface. When shaking, hold the container with one hand, let the arm hang naturally, and shake the wrist slightly.

[0172] Test Sample: Examples 1-13 and Comparative Examples 1-10

[0173] Observation Result: As shown in Table 1.

[0174] Table 1

[0175]

[0176]

[0177] The observation results show that the samples obtained in Examples 1-13 are all clear and transparent three-layer emulsions with clear interfaces between the layers. The emulsification occurs after shaking three times, and the emulsification is maintained for 5 minutes. After 5 minutes, demulsification occurs within 8 hours, and the sample returns to the initial state after 8 hours.

[0178] The sample obtained in Comparative Example 1 has a low osmotic pressure due to the absence of sodium chloride in the water phase, which prevents the emulsifier from being released from the oil layer. Under the action of the emulsifier, part of the oil phase and part of the water phase form an emulsion layer. This emulsion layer cannot achieve a clear and transparent three-layer state after long-term standing. After shaking, the middle layer is still an emulsion layer, not an emulsifier layer.

[0179] The sample obtained in Comparative Example 2 has a high proportion of polar oil, and the emulsifier is completely dissolved in the oil phase. The entire sample is in a two-layer state composed of an oil layer and a water layer. The emulsifier cannot emulsify the sample, and even after shaking, the sample cannot be emulsified but is in a mixed state of oil and water. The sample quickly returns to a two-layer state of oil and water. The same phenomenon occurs in Comparative Example 6, which contains only polar oil. The sample obtained is also in a two-layer state.

[0180] The sample obtained in Comparative Example 3 has a low proportion of polar oil. Although it can form a three-layer serum similar to Example 1, it cannot recover to the initial state after 8 hours of emulsification. After 48 hours of observation, it still cannot recover to the initial state. The same phenomenon occurs in Comparative Example 7.

[0181] The sample obtained in Comparative Example Four is in a three-layer state, but the middle layer is an emulsion layer formed by the emulsifier, part of the oil phase and part of the water phase (see Figure 3 ), instead of an emulsifier layer. After shaking, the middle layer is still an emulsion layer, instead of an emulsifier layer.

[0182] The sample obtained in Comparative Example Five is in a two-layer state of an oil layer and a water layer, and shaking cannot form an emulsion. After shaking, the water phase and the oil phase quickly return to the two-layer state of an oil layer and a water layer.

[0183] The sample obtained in Comparative Example Eight is in a two-layer state of an emulsifier layer on top of a water layer, and shaking cannot emulsify. After shaking, the water phase and the emulsifier quickly return to the two-layer state of an emulsifier layer and a water layer. Similarly, Comparative Example Nine contains only an emulsifier layer and an oil layer, and shaking cannot emulsify. After shaking, the emulsifier and the oil phase quickly return to the two-layer state of an emulsifier layer and an oil layer.

[0184] The sample obtained in Comparative Example Ten is exactly the same as the sample of Example One, but the preparation method of this comparative example is different from that of Example One. Since the emulsifier is in a precipitated state before filling, it is difficult to control the stability of the product quality during industrial production, and since the emulsifier itself has high viscosity and low content, the total amount of the product is also small, which is not suitable for filling alone. Therefore, the method of Comparative Example Ten is difficult to realize industrialization.

[0185] 2. Stability test

[0186] The test conditions are four, which are: -18℃ light-avoiding storage, 25℃ light-avoiding storage, 25℃ light-exposed storage (light intensity is 4500±500lx), 50℃ light-avoiding storage, and cold and hot cycle storage (-18℃ to 50℃ cycle, 7 days per cycle);

[0187] Control condition: 4±1℃ light-avoiding;

[0188] Sample: Select the samples obtained in Examples One to Eight in a sealed state, prepare 5 samples for each example, and place four samples in four test conditions, and one sample in the control condition. Observe the changes of the samples in the test conditions relative to the control group;

[0189] Scoring standard: compare the appearance of the samples in the test conditions with the samples in the control condition. If it is consistent with the control group, it is scored as 0; if there is a slight change but it is still applicable, it is scored as 1; if there is a significant change and it is unacceptable, it is scored as 2. The higher the score, the greater the change in appearance. Appearance includes the clarity of the interface between the three layers, the clarity and transparency, the odor, and the color.

[0190] The test results are shown in Table 2.

[0191] Table 2

[0192]

[0193]

[0194] From Table 2, it can be seen that the samples obtained in Examples 1 to 8 have the same appearance as the control group under each test condition, indicating that they have good stability.

[0195] The above description is merely preferred embodiments of the present application, and not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A three-layer serum suitable for dry skin, characterized in that, It includes an oil layer, an aqueous layer, and an emulsifier layer between the oil layer and the aqueous layer. The oil layer contains non-polar grease with a polarity index of 0 to 1.5 and polar grease with a polarity index of 1.5 to 5.

0. The aqueous layer has an osmotic pressure ≥60 mOsm / L. The mass ratio of polar oils to non-polar oils is 1:1.7 to 1:7, and the emulsifier layer accounts for 0.015% to 0.06% of the total mass.

2. The three-layer serum suitable for dry skin as described in claim 1, characterized in that, The mass ratio of oil layer to water layer is 1:0.4 to 1:

7.

3. The three-layer serum suitable for dry skin as described in claim 1, characterized in that, Polar oils include one or more of the following: coconut oil-caprylate / capric acid ester, isopropyl stearate, caprylic / capric triglyceride, jojoba seed oil, sunflower seed oil, avocado oil, olive fruit oil, castor seed oil, and PPG-15 stearyl alcohol ether. Non-polar oils include one or more of the following: C9-12 alkyl, C13-14 alkyl, C13-15 alkyl, C15-19 alkyl, C15-23 alkyl, C18-21 alkyl, C10-11 isoparaffins, C10-12 isoparaffins, C10-13 isoparaffins, C12-14 isoparaffins, C13-14 isoparaffins, C13-16 isoparaffins, mineral oil, and squalane.

4. The three-layer serum suitable for dry skin as described in claim 1, characterized in that, The water layer includes water and solutes dissolved in the water, wherein the solutes include one or more of the following: moisturizers, antioxidants, skin conditioning agents, pH adjusters, anti-wrinkle agents, osmotic pressure regulators, preservatives, and thickeners. The osmotic pressure of the water layer is 310 mOsm / L to 700 mOsm / L.

5. The three-layer serum suitable for dry skin as described in claim 1, characterized in that, The emulsifier layer includes an emulsifier that is soluble in polar oils and insoluble in non-polar solvents at temperatures of 0–40°C. The mass ratio of emulsifier to polar oil is not less than 1:

40.

6. The three-layer serum suitable for dry skin as described in claim 5, characterized in that, The emulsifier is a glycolipid and / or a compound formed by PEG-20 glycerol triisostearate and polyglycerol-2 sesquioctanoate, wherein the mass ratio of PEG-20 glycerol triisostearate to polyglycerol-2 sesquioctanoate in the compound is 1:4 to 4:

1.

7. The use of a three-layer serum suitable for dry skin as described in any one of claims 1-6 in the preparation of skin care products.

8. A method for preparing a three-layer serum suitable for dry skin, characterized in that, Includes the following steps: S1. Prepare an aqueous phase with an osmotic pressure of not less than 60 mOsm / L; S2. Dissolve the emulsifier in a polar oil with a polarity index of 1.5 to 5.0; S3. Take the aqueous phase from step S1, the polar oil containing the emulsifier from step S2, and the non-polar oil phase with a polarity index of 0 to 1.5, mix them, and after standing, the aqueous phase forms an aqueous layer, the oil phase forms an oil layer, and the emulsifier precipitates from the polar oil to form an emulsifier layer, which is located between the aqueous layer and the oil layer, that is, a three-layer essence is obtained; wherein, the mass ratio of polar oil to non-polar oil is 1:1.7 to 1:7, and the emulsifier layer accounts for 0.015% to 0.06% of the total mass.

9. The method as described in claim 8, characterized in that, In step S1, the aqueous phase includes water and solutes dissolved in water, wherein the solutes include one or more of the following: moisturizers, antioxidants, skin conditioning agents, pH adjusters, anti-wrinkle agents, osmotic pressure regulators, preservatives, and thickeners.

10. The method as described in claim 9, characterized in that, The osmotic pressure of the aqueous phase is 310 mOsm / L to 700 mOsm / L.

11. The method as described in claim 8, characterized in that, In step S2, the polar oils include one or more of the following: coconut oil-caprylate / capric acid ester, isopropyl stearate, caprylic / capric triglyceride, jojoba seed oil, sunflower seed oil, avocado oil, olive fruit oil, castor seed oil, and PPG-15 stearyl alcohol ether.

12. The method as described in claim 8, characterized in that, In step S3, the non-polar oils include one or more of the following: C9-12 alkane, C13-14 alkane, C13-15 alkane, C15-19 alkane, C15-23 alkane, C18-21 alkane, C10-11 isoparaffin, C10-12 isoparaffin, C10-13 isoparaffin, C12-14 isoparaffin, C13-14 isoparaffin, C13-16 isoparaffin, mineral oil, and squalane. The mass ratio of the oil phase to the water phase is 1:0.4 to 1:

7.

13. The method as described in claim 8, characterized in that, The mass ratio of emulsifier to polar oil is not less than 1:40; Emulsifiers are insoluble in nonpolar solvents at temperatures between 0 and 40°C.

14. The method as described in claim 8, characterized in that, The emulsifier is a glycolipid and / or a compound formed by PEG-20 glycerol triisostearate and polyglycerol-2 sesquioctanoate, wherein the mass ratio of PEG-20 glycerol triisostearate to polyglycerol-2 sesquioctanoate in the compound is 1:4 to 4:1.

Images