Preparation method of liquid crystal facial cleanser

Abstract

The preparation method of the liquid crystal facial cleanser comprises the following steps: respectively pumping a water phase and an oil phase into a channel of a micro-channel reactor, and mixing to obtain a uniform and stable emulsified liquid, namely the facial cleanser; the temperature of a heat exchanger of the micro-channel reactor is 82 DEG C. The liquid crystal facial cleanser obtained through the micro-channel has the characteristics and advantages that the liquid crystal facial cleanser has cleaning power, and dirt, grease, cosmetics and the like can be more effectively removed due to a surfactant and functional components in the liquid crystal facial cleanser; due to the emulsion-shaped structure of the liquid crystal facial cleanser, the liquid crystal facial cleanser is soft and fine in touch feeling when in use, and does not bring over-stimulation and tight feeling to the skin; components with moisturizing and moistening effects are often added into the liquid crystal facial cleanser, so that sufficient moisture and nutrition can be provided for the skin while cleaning is carried out; and the liquid crystal facial cleanser has good stability and can keep an emulsion structure for a long time without separation, so that the service life of the product is prolonged.

Description

Technical Field

[0001] The invention relates to a method for preparing a liquid crystal facial cleanser, and belongs to the technical field of liquid crystal cosmetic preparation. Background Art

[0002] Liquid crystal cosmetics are mainly based on the unique properties of the liquid crystal structure, using the fluidity of liquid crystal substances and the regularity of molecular arrangement to achieve functions such as moisturizing and sustained release of active ingredients.

[0003] Liquid crystal technology is applied in cosmetics, mainly by utilizing the special structure of liquid crystal substances. There are various types of liquid crystals, among which the structure of lyotropic liquid crystal is similar to that of human skin. Lyotropic liquid crystal can be divided into three types according to the different water content: lamellar liquid crystal, hexagonal liquid crystal, and cubic liquid crystal. At present, lamellar liquid crystal is the most widely used in cosmetics on the market. The lamellar liquid crystal structure is a structure with both oil phase layer and water phase layer formed by the interface between amphiphilic molecules and water. This special structure can make the active ingredients in cosmetics be better preserved in the liquid crystal layer. When used, because it is contained in the lamellar structure, the active ingredients are slowly released, which can have a certain soothing effect, and can make the utilization rate of the active ingredients higher, achieving the goal of green and economy. Liquid crystal state is a material state between liquid and solid (liquid crystal structure has no solid state, all are liquid, the difference between different lyotropic liquid crystals is that the different temperature and water content lead to different structures, different viscosities but still liquid), it has both the fluidity of liquid and the regularity of solid molecular arrangement. This characteristic enables liquid crystal cosmetics to form a stable film on the skin surface, which plays a role in moisturizing and protecting the skin. Specifically, the application of liquid crystal technology in cosmetics is mainly reflected in the following aspects:

[0004] Moisturizing effect: Traditional emulsification structures, such as O / W or W / O emulsification systems, can only achieve the functions of moisturizing or degreasing, and it is difficult to ensure both effects in one product. For example, moisturizing products often bring greasy feeling, etc., while liquid crystal emulsifiers can achieve the above two effects at the same time due to their special double-layer structure. The layered structure of liquid crystal emulsion allows oil and water to combine in layers to form a water-locking barrier, effectively lock in moisture, inhibit moisture evaporation, and thus improve the skin's water retention capacity. Experiments have confirmed that the moisturizing effect of liquid crystal emulsion can be increased by 3 times compared with traditional emulsion.

[0005] Active ingredient sustained release: Liquid crystal structure can slowly release active ingredients. Generally, the active ingredients in cosmetics are irritating to human skin. If the amount of active ingredients is too large, it may cause skin allergies. If the amount of active ingredients is too low, the efficacy will not be obvious. The liquid crystal structure can solve this problem very well. On the one hand, its special structure allows the active ingredients to be released slowly, avoiding allergies caused by skin contact with active ingredients in a short period of time. On the other hand, it can save the amount of active ingredients, thereby reducing corporate costs. These ingredients stay on the skin for a longer time, so as to give full play to their efficacy. This feature helps to improve the efficacy of cosmetics and enable the skin to better absorb active ingredients.

[0006] Simulating the skin barrier: The outermost layer of the skin, the stratum corneum, has a similar structure to a wall, including cornified cells as "bricks" and lipid structures as "cement". Studies have found that there is a lamellar gel-phase lipid structure formed by oil in the stratum corneum, which is very similar to the lamellar liquid crystal emulsification structure, indicating that liquid crystal technology can simulate and enhance the natural barrier function of the skin.

[0007] Based on the above main functions, the existing liquid crystal technology is mostly used in skin care cosmetics, but rarely used in cleaning products, especially in the preparation of facial cleansers, and there are fewer formulas for liquid crystal facial cleansers.

[0008] At present, patent CN2020115747249, a liquid crystal amino acid cleanser and its preparation method, and patent CN2019106081039, a cleanser containing a liquid crystal structure and its preparation method, both adopt conventional mixing and stirring methods, and then use staged stirring speed and temperature to form liquid crystals, which is relatively complicated to operate.

[0009] Therefore, it is necessary to provide a new method for preparing a liquid crystal cleanser. Summary of the invention

[0010] In order to solve the deficiencies of the prior art, the object of the present invention is to provide a method for preparing a liquid crystal cleanser.

[0011] In order to achieve the above object, the present invention adopts the following technical solution:

[0012] A method for preparing a liquid crystal cleanser, comprising: pumping a water phase and an oil phase into a channel of a microchannel reactor respectively, and mixing them to obtain a uniform and stable emulsified liquid, which is the cleanser;

[0013] The heat exchanger temperature of the microchannel reactor is 82°C.

[0014] The above-mentioned pumping speed ratio of the water phase and the oil phase is determined by the volume ratio of the water phase and the oil phase.

[0015] In terms of mass ratio, the oil phase comprises 4% olive oil, 4% shea butter, 6% jojoba oil and 1% cetyl alcohol;

[0016] The water phase comprises 3% glycerol, 2% emulsifier, 3% hydrogenated phospholipids, 1% lauryl glucoside, 1% erythritol, 0.5% sodium hyaluronate, 0.5% starch, and the balance is water.

[0017] The inner diameter of the channel of the above-mentioned microchannel reactor is 21.6 mm.

[0018] Furthermore, the pumping speed of the oil phase is 1 ml / min.

[0019] Furthermore, the emulsified liquid does not contain mixed waste.

[0020] The time for receiving the waste is Ts=2.7÷V×60×5,

[0021] Where Ts is the waste receiving time, V is the total flow rate, V = 5 ml / min, 2.7 is the liquid holding volume of the reaction plate, 60 represents 60 seconds, and 5 is to ensure 5 times the residence time to ensure that the inside of the reactor plate is clean.

[0022] Before sample preparation, the microchannel is cleaned with water and ethanol in turn. There will be residues after cleaning. Therefore, the products obtained in the initial stage of our reaction materials are affected and the quality is not high. These products are waste.

[0023] The present invention is beneficial in that:

[0024] The preparation method of a liquid crystal facial cleanser of the present invention obtains an optimal liquid crystal facial cleanser by combining the process and the formula, and has the following advantages:

[0025] 1. Efficient reaction: Compared with the traditional emulsification method, the microchannel structure of the microchannel reactor can provide a large specific surface area and high mass transfer efficiency, allowing the reactants to contact and react more fully. This leads to a faster reaction rate and a higher reaction conversion rate, thereby achieving an efficient reaction process. For example, microchannel emulsification only takes 5 minutes and 50 seconds, while traditional process emulsification takes about 15-20 minutes. Save time, save energy, lower carbon and greener.

[0026] 2. Precise control: Microchannel reactors can precisely control reaction conditions, such as temperature, pressure, flow rate, etc. By adjusting these parameters, precise control of the reaction process can be achieved, thereby optimizing the reaction conditions and improving the selectivity and purity of the product. The traditional emulsification process is not stirred sufficiently. Through a polarizing microscope, it can be seen that the prepared cleanser contains oil droplets. In addition, there are many uncertain factors in the traditional process, such as being affected by various factors in the air, and there are many inaccuracies.

[0027] 3. Enhanced safety: Due to the short residence time of the reactants in the microchannel reactor in the tiny channels, the reaction heat can diffuse and dissipate faster, reducing the risk of hot spot accumulation and explosion, thereby improving the safety of the reaction.

[0028] 4. Low waste generation: The high efficiency and precision of the microchannel reactor allow the reactants to be more fully converted into the desired products, effectively reducing waste generation and improving the economy and environmental friendliness of the reaction.

[0029] 5. Continuity: Unlike batch reactions, microchannel reactors can achieve continuous flow operation. This continuous operation mode eliminates the intermittent steps in traditional reactions, reduces reaction time and equipment space, and improves production efficiency.

[0030] 6. The product characteristics and advantages of the liquid crystal cleanser obtained through the microchannel are: it has cleaning power. Due to the surfactants and functional ingredients in the liquid crystal cleanser, it has a good cleaning effect and can effectively remove dirt, grease and makeup; it is comfortable. The emulsion-like structure of the liquid crystal cleanser makes it soft and delicate when used, and will not cause excessive stimulation and tightness to the skin; it is moisturizing. Liquid crystal cleansers often add ingredients with moisturizing and nourishing effects, which can provide sufficient moisture and nutrition to the skin while cleaning; it has stability. The liquid crystal cleanser has good stability and can maintain the emulsion structure for a long time without separation, extending the service life of the product. It can simulate the liquid crystal structure of the cell membrane very well. Active ingredients such as moisturizers can be wrapped in the hydrophobic water between the inner water phase and the double-layer structure in these structures. When consumers use the product, the product can be better spread on the skin and can be better absorbed by the skin.

[0031] The preparation method of a liquid crystal cleanser of the present invention has broad application prospects. Through comprehensive consideration and optimization of the formula, process and product characteristics, a liquid crystal cleanser product with excellent performance and stable quality can be produced to meet consumers' needs for cleanliness, comfort and moisturizing. Further research and exploration will help promote the development and innovation of liquid crystal cleansers, meet the needs of different consumer groups, and bring more possibilities to the cleansing product market. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The effect of different amounts of emulsifier on the liquid crystal structure.

[0033] Figure 2 The effect of different amounts of co-emulsifier on the liquid crystal structure.

[0034] Figure 3 The effect of different amounts of oil on the liquid crystal structure.

[0035] Figure 4 The influence of the polarity of oil on the liquid crystal structure.

[0036] Figure 5 The effect of different amounts of glycerol on the liquid crystal structure.

[0037] Figure 6 The effect of different amounts of sodium hyaluronate on the liquid crystal structure.

[0038] Figure 7 This is the liquid crystal structure in Example 1.

[0039] Figure 8 This is the liquid crystal structure in Comparative Example 1. DETAILED DESCRIPTION

[0040] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] The formula of liquid crystal cleanser is shown in Table 1 below:

[0042]

[0043]

[0044] Table 1

[0045] Example 1

[0046] Liquid crystal cleanser preparation method:

[0047] (1) Turn on the microchannel reactor equipment and adjust the syringe parameters to an inner diameter of 21.6 mm.

[0048] (2) Two syringes (channels) suck ethanol, then adjust the flow rate of the two pumps to 2 ml / min and start the cleaning equipment; after cleaning, adjust the temperature of the heat exchanger to 82°C for preheating.

[0049] (3) After preheating, start injecting the water phase and the oil phase. Adjust the flow rate ratio of the two pumps according to the ratio of the water and oil phases. Water: oil = 3:1, and the flow rate is also set to 3:1.

[0050] (4) Use a beaker to collect the waste liquid. The time for collecting the waste is calculated using the formula Ts = 2.7 ÷ V × 60 × 5. Ts is 202.5 seconds.

[0051] (5) After the waste is collected, the beaker is changed to receive the newly formed emulsion. The turbid emulsion drips into the beaker evenly and continuously through the pipe without obvious stratification.

[0052] (6) The reaction was completed in 4 minutes and 32 seconds.

[0053] (7) After the reaction is finished, the heat exchanger temperature is adjusted to 20°C to cool down; at the same time, two syringes are used to absorb water to clean the equipment, and the pump rates of the two syringes are adjusted to the same ratio. When the temperature drops to 20°C, two syringes are used to absorb ethanol to clean the equipment.

[0054] In a microchannel reactor, the flow rate and flow rate of the liquid (water phase and oil phase) can be controlled by microfluidic technology, so that the two phases can enter the microchannel in a precise and controllable manner.

[0055] At the beginning, the water phase and the oil phase contact to form a mixing interface, on which a small interface area is formed due to the surface tension between the two liquids. As the flow rate increases when the fluid passes through the microchannel, shear force and turbulence effects are generated. This convection mixing can promote the increase of the boundary area between the water phase and the oil phase, thereby enhancing the mixing degree of the two phases and forming fine emulsion droplets. Under the action of turbulence and shear, the newly formed droplets are affected by the flow of the fluid and move in the direction of the flow of the fluid. When multiple droplets meet, they will eventually merge into larger droplets. Finally, when the water phase and the oil phase are fully mixed in the microchannel continuous reactor, a uniform and stable emulsified liquid will be formed.

[0056] The test equipment used in the present invention is: microchannel reactor, Corning continuous microchannel reactor Nebula version.

[0057] Comparative Example 1

[0058] Before preparing samples, thoroughly disinfect and clean all equipment, beakers, homogenizer heads, etc.

[0059] (1) olive oil, jojoba seed oil, shea butter, and cetyl alcohol are added to a beaker in sequence, heated in a water bath to about 80° C. under stirring, and after they are completely dissolved, the beaker is heated continuously to obtain phase A, i.e., an oil phase;

[0060] (2) Add erythritol, sodium hyaluronate, starch, soybean lecithin, hydrogenated phospholipids, and lauryl glucoside into a beaker in sequence, stir and disperse, add deionized water, heat and stir in a water bath to about 80° C., and after complete dissolution, prepare the β phase in phase B, the aqueous phase.

[0061] (3) Quickly add phase B to phase A and add the water phase to the oil phase, and stir to homogenize and emulsify. At the beginning, it is a W / O type emulsion. As the water phase is added, it becomes an O / W type emulsion, which is called a concentrated emulsion. Stir while adding.

[0062] (4) After stirring evenly, dilute with glycerol at room temperature and stir to finally obtain an emulsion.

[0063] (5) Take samples and observe the liquid crystal structure under a polarizing microscope.

[0064] A. Performance test, see Table 2 below:

[0065]

[0066]

[0067] Table 2

[0068] As can be seen from Table 2 above, the liquid crystal facial cleanser (Example 1) exhibits a light and cool texture during use, does not leave greasy residue on the skin surface, and provides a fresh and clean use experience.

[0069] The liquid crystal cleanser prepared by the conventional process (Comparative Example 1) is slightly more greasy and sticky than the liquid crystal cleanser prepared by the microchannel (Example 1).

[0070] Liquid crystal cleanser can provide necessary moisture to the skin while cleansing. It is easily absorbed by the skin, effectively locks in moisture, keeps the skin soft and smooth, and greatly reduces the feeling of tightness caused by cleansing.

[0071] Under the influence of microchannel reaction, the liquid crystal cleanser is quickly absorbed by the skin when applied to the skin, leaving no sticky or heavy feeling. During the skin massage, the liquid crystal cleanser shows excellent oil, dirt and makeup removal effects, ensuring the skin is fresh and clean. After using the liquid crystal cleanser, the skin's moisture level is significantly improved. It can provide sufficient moisture to the skin, maintain the skin's softness and smoothness, and is an ideal choice for those who pursue the dual effects of cleansing and moisturizing.

[0072] B. Discussion of efficacy, see Table 3 below:

[0073]

[0074]

[0075] Table 3

[0076] As can be seen from Table 3 above, the microchannel process has a slight advantage over the traditional process in terms of water transfer, while the oil content, skin color and sensitivity indicators are slightly lower than those of the traditional process. It is worth noting that in terms of pigment transfer, the microchannel process performs particularly well, with the pigment content reduced by about half, which indicates that the microchannel reactor can achieve more efficient mixing and reaction during the reaction of the water phase and the oil phase.

[0077] It can be seen that the conventional liquid crystal cleanser (Comparative Example 1) has a delicate touch when in contact with the skin, does not cause roughness or irritation, and can gently contact the skin surface. The texture of the cleanser after application has a light and refreshing feeling, and is not very greasy, and remains on the skin surface, giving a fresh and comfortable feeling. Moisturizing degree, the cleanser has a good degree of moisturizing to the skin after use, is easy to absorb, can provide sufficient moisture, keep the skin soft and smooth, and reduce tightness.

[0078] The liquid crystal cleanser (Example 1) after the microchannel reaction has a soft, smooth and delicate touch when gently touched with fingers. The liquid crystal cleanser is applied to the skin and can be quickly absorbed by the skin without leaving a sticky or heavy feeling. The liquid crystal cleanser is used to massage the skin and its effect on removing grease, dirt and makeup is observed. It is found that it can effectively clean the skin and make it feel refreshed and clean. After using the liquid crystal cleanser, the skin's moisturizing degree is observed and it is found that it can provide sufficient moisture and keep the skin soft and smooth.

[0079] By testing the liquid crystal cleansers produced by the two processes respectively, it can be seen from the test results that the moisture content of the microchannel is slightly more than that of the traditional technology, and the oil content, skin color, and sensitivity are slightly less than that of the traditional technology, but the pigment is obviously reduced by about half. This shows that the microchannel reactor is more complete and sufficient in reacting the water phase and the oil phase.

[0080] C. Formula

[0081] C1. Effect of emulsifier on liquid crystal structure

[0082] The present invention uses lecithin emulsifiers, which have strong emulsifying ability and good stability, and can effectively prevent problems such as emulsion stratification. Lecithin has the ability to form a protective film on the surface of the skin, thereby protecting the skin from external stimulation and damage; in addition, it can also produce a strong affinity with the stratum corneum of the skin, which helps to repair the sebum barrier of damaged skin. Lecithin also exhibits excellent hydration. It has an inhibitory effect on a variety of microorganisms and does not produce drug resistance.

[0083] Lecithin and its derivatives can not only be used as a natural moisturizer, but also an excellent surfactant. In addition, lecithin is not only a key component of cell membranes, but also the most abundant phospholipid substance in the human body. With the help of the lamellar liquid crystal structure formed by lecithin, it can effectively simulate the human stratum corneum and promote the realization of the "second skin" effect.

[0084] In liquid crystal cleansers, the amount of emulsifier used will affect the liquid crystal structure. Emulsifiers are surfactants that can mix oil and water, and they play a role in emulsification, stabilization and regulating the properties of the emulsion.

[0085] The present invention uses emulsifiers (soy lecithin and hydrogenated lecithin) with a mass proportion of 2%, 3%, 4%, 5%, 6%, and 7% to prepare liquid crystal cleansing milk, such as Figure 1 As shown in (2%-A, 3%-B, 4%-C, 5%-D, 6%-E, 7%-F), the liquid crystal structure with an emulsifier dosage of 5% is better. It can be seen that the change in the dosage of the emulsifier will directly affect the emulsification effect and stability of the liquid crystal cleanser. The right amount of emulsifier can effectively disperse the oil and water phases and form an emulsion-like structure. Too little emulsifier will cause oil and water separation and fail to form a stable emulsification system; while too much emulsifier may cause the emulsion to be too thick, affecting the formation and performance of the liquid crystal structure.

[0086] C2. Effect of emulsifier on liquid crystal structure

[0087] Since there are many types of oils used in cosmetics, a single liquid crystal emulsifier is often not enough to emulsify all oils. This insufficiency is due to the differences in compatibility between liquid crystal emulsifiers and various oils, which prevents them from combining to form a uniform and stable liquid crystal layer structure.

[0088] Therefore, it is necessary to introduce an auxiliary emulsifier. The mechanism of action of the auxiliary emulsifier is to interact with the gel network formed by the liquid crystal emulsifier, thereby enhancing the stability of the lamellar liquid crystal structure. The present invention selects soybean lecithin and hydrogenated lecithin for compounding.

[0089] like Figure 2 As shown, the liquid crystal structures are prepared according to the ratio of 1:2 (G), 1:3 (H), 2:2 (I), and 2:3 (K). It can be seen that Figure 2 The liquid crystal structure in K is better, that is, the liquid crystal structure of the cleanser prepared by compounding soybean lecithin and hydrogenated lecithin in a ratio of 2:3 is better.

[0090] It can be seen that different compounding ratios will significantly affect the formation of liquid crystal structure and its stability.

[0091] Therefore, the appropriateness of the ratio of liquid crystal emulsifier to co-emulsifier is directly related to the stability of the final product and the skin feel during use. If the ratio is too low, the product may be too fluid and unstable, affecting the storage and use of the product. If the ratio is too high, the product may appear greasy during use, and the stability will also be affected.

[0092] C3. Effect of oil on liquid crystal structure

[0093] like Figure 3As shown, the liquid crystal structure in the cleansing milk with different oil dosages (olive oil, shea butter, jojoba seed oil, cetyl alcohol mixed in the same proportion) of 14% (L), 15% (M), 16% (N) and 17% (O) by mass.

[0094] Depend on Figure 3 It can be seen that when the amount of oil is 15%, the liquid crystal structure is more obvious, the distribution is more uniform, and there are no oil bubbles.

[0095] Therefore, with the addition of liquid grease, the liquid crystal structure gradually changes from a solid Maltese cross to a hollow Maltese cross. This is because the addition of liquid grease changes the arrangement of liquid crystal molecules, thus affecting the optical properties of the liquid crystal.

[0096] As the amount of oil continues to increase, the liquid crystal structure gradually weakens. This is because too much oil will weaken the interaction between liquid crystal molecules, thereby reducing the optical anisotropy of the liquid crystal. This phenomenon shows that the effect of the amount of oil on the liquid crystal structure is limited, and too much oil will destroy the stability of the liquid crystal. Therefore, the amount of oil needs to be precisely controlled to achieve the desired liquid crystal properties.

[0097] C4. Effect of the polarity of oils and fats on the liquid crystal structure

[0098] like Figure 4 Shown are the liquid crystal structures in facial cleansers prepared using non-polar oil jojoba seed oil (P) and polar oil olive oil (Q).

[0099] Depend on Figure 4 It can be seen that the non-polar oil jojoba seed oil has a better liquid crystal structure, while the polar oil olive oil has a rare liquid crystal structure. The stronger the polarity of the oil, the lower the maximum content of liquid oil that can form a liquid crystal structure. The reason is that the hydrophilic head of the emulsifier is a polar group. The stronger the polarity of the oil, the easier it is to embed into the polar head between the emulsifiers, and the easier it is to disrupt the directional arrangement of the emulsifier and the solid oil, and the lower the maximum content of liquid oil that can form a liquid crystal structure.

[0100] Jojoba seed oil has the characteristics of high hydrophilicity and low polarity, which can help increase the hydrophilicity of liquid crystal cleansers and provide good lubrication and moisturizing effects. Due to its low polarity, jojoba oil usually does not have a significant destructive effect on the liquid crystal structure, which helps stabilize and form the liquid crystal structure.

[0101] Olive oil is rich in vitamin E and antioxidants, and has the dual effects of nourishing and protecting the skin. Incorporating it into liquid crystal cleansing milk not only enhances the nutritional value of the product, but also brings gentle and effective cleaning power. However, the higher fatty acid content and higher polarity of olive oil may have a certain impact on the structure of liquid crystal molecules, which may weaken their stability.

[0102] C5. Effect of glycerol on liquid crystal structure

[0103] like Figure 5 The figures show the liquid crystal structures in the cleansing milks with glycerol addition amounts of 1% (R), 2% (S), 3% (T), and 4% (U).

[0104] The present invention studies the influence of glycerol dosage on the stability of the water phase by changing the dosage of glycerol, and finally obtains the optimal formula.

[0105] Depend on Figure 5 It can be seen that relatively complete and ordered liquid crystal structures can be observed from Figure R and Figure T, but the number of liquid crystals in Figure T is larger and the distribution is more uniform. The difference in the formula of these two substances is that the added mass percentage of glycerol is 1% and 3% respectively, indicating that the increase in the amount of glycerol is conducive to the formation of liquid crystals.

[0106] The introduction of glycerol effectively increases the viscosity of the water phase (dispersion medium) and enhances the affinity between the lipid raw material and the emulsifier in the dispersed phase, which helps to enhance the dispersion effect of the emulsified oil droplets in the water phase. Therefore, the glycerol content has a great influence on the liquid crystal. As the glycerol content increases, the orientation degree of the liquid crystal decreases. Obviously, if the amount of glycerol added is too high, it may combine with water through hydrogen bonds, form hydration groups and enter the liquid crystal structure layer, which will destroy the orderly arrangement of the liquid crystal.

[0107] In addition, the addition of glycerol as the water phase will indirectly reduce the proportion of amphiphilic molecules in the lamellar liquid crystal, thereby gradually transforming the lamellar liquid crystal into a hexagonal liquid crystal structure, and the viscosity of the liquid crystal emulsification system will also gradually increase, which has a certain influence on the formation of the emulsification system and is not conducive to the formation of the lamellar liquid crystal structure. Too high a glycerol content is also not conducive to the formation of liquid crystals. Figure 5 As shown in Figure 1, the liquid crystal structure is broken, chaotic, incomplete and uneven. This may be because the increase in the amount of polymer used leads to an increase in the viscosity of the system, which causes the polymer to form a tighter cross-linked network and breaks the orderly arrangement of the liquid crystal. In addition, as the polymer content increases, the viscosity of the system decreases, but there is no obvious effect on the oil-based emulsion. Therefore, the amount of polymer used should be appropriate while ensuring that the stability and consistency of the system are not affected.

[0108] C6. Effect of Sodium Hyaluronate on Liquid Crystal Structure

[0109] like Figure 6 The figure shows the liquid crystal structure of the cleansing milk with the addition amount of sodium hyaluronate being 0.1% (V), 0.3% (W), and 0.5% (X).

[0110] Depend on Figure 6It can be seen that when the amount of sodium hyaluronate added is 0.5%, the distribution of the liquid crystal structure is relatively uniform and stable. The water-soluble polymer not only prolongs the stability of the product, but also helps to form and stabilize the lamellar liquid crystal structure. The addition of sodium hyaluronate causes a large number of water molecules in the water layer to be bound around it, and there is an interaction between hyaluronic acid and lecithin molecules, which improves the orderliness of the liquid crystal lamellar structure and reduces the interlayer distance of the liquid crystal. This shows that the lecithin / hyaluronic acid / water lamellar liquid crystal has a stronger capacity for water and has a stronger water retention performance.

[0111] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A method for preparing a liquid crystal cleanser, characterized in that: By pumping the water phase and the oil phase into the channel of the microchannel reactor respectively and mixing them, a uniform and stable emulsified liquid is obtained, which is the liquid crystal cleanser; The heat exchanger temperature of the microchannel reactor is 82°C.

2. The method for preparing a liquid crystal facial cleanser according to claim 1, characterized in that: The pumping speed ratio of the water phase and the oil phase is determined by the volume ratio of the water phase to the oil phase.

3. The method for preparing a liquid crystal facial cleanser according to claim 1, characterized in that: In terms of mass ratio, the oil phase comprises 4% olive oil, 4% shea butter, 6% jojoba oil and 1% cetyl alcohol; The water phase includes 3% glycerin, 2% emulsifier, 3% hydrogenated phospholipids, 1% lauryl glucoside, 1% erythritol, 0.5% sodium hyaluronate, 0.5% starch, and the balance is water.

4. The method for preparing a liquid crystal facial cleanser according to claim 1, characterized in that: The inner diameter of the channel of the microchannel reactor is 21.6 mm.

5. The method for preparing a liquid crystal facial cleanser according to claim 4, characterized in that: The pumping speed of the oil phase was 1 ml / min.

6. The method for preparing a liquid crystal facial cleanser according to claim 5, characterized in that: The emulsified liquid does not contain mixed waste materials, The time for receiving the waste is Ts=2.7÷V×60×5, Where Ts is the waste receiving time and V is the total flow rate.

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