Hydrophobic powder water dispersion slurry as well as preparation method and application thereof

Abstract

The invention relates to the field of cosmetic raw materials, and particularly discloses hydrophobic powder water dispersion slurry as well as a preparation method and application thereof. The hydrophobic powder water dispersion slurry comprises the following components in percentage by mass: 50-80% of inorganic toner, 5-20% of a dispersing agent, 0.1-5% of polyol, 0.1-2% of a preservative and the balance of water, the inorganic toner is subjected to surface modification treatment, and a modifier adopted in the surface modification treatment comprises one or a combination of two or more of amino acids, bionic sebum, a silicon-containing treating agent, higher fatty acid and salts thereof. The hydrophobic powder water dispersion slurry can be used in cosmetics such as colored face cream, tone-up cream, sun screen and lip glaze, and has the advantages of high storage stability, high solid content and narrow particle size distribution.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cosmetic raw materials, more particularly, it relates to a hydrophobic powder water dispersion paste and a preparation method and application thereof. BACKGROUND

[0002] In the color cosmetic product, inorganic powder pigments occupy an indispensable important position, among which titanium dioxide, iron oxide, ultramarine and chromium oxide green coloring agents are the core raw materials. However, such inorganic powder pigments have inherent defects: the surface energy is high, and the particles are prone to agglomeration; the surface hydroxyl group of inorganic color powder without surface treatment will form a hydroxyl network, resulting in agglomeration and uneven dispersion in the application process. At the same time, due to the large interfacial tension between the hydrophilic surface and the oil, it is easy to produce stratification after mixing with oil, which affects the product quality. In order to improve the above problems, the industry often uses surface modification technology to treat inorganic pigments, which can effectively eliminate the agglomeration caused by hydrogen bonds, promote the uniform spreading of the color powder, and enhance its hiding power; at the same time, it can reduce the friction resistance of the color powder surface, improve the smoothness and extensibility of the product, and improve the waterproof and sweat resistance. However, the pigment dispersion paste on the market has obvious limitations: it shows good dispersibility and stability in oily systems or water-in-oil formulations, but it is difficult to disperse uniformly in aqueous systems or oil-in-water emulsion systems. In addition, the existing water-based color paste is a low pigment content product, and the inorganic pigment content is usually not more than 40%. This situation brings many inconveniences to practical application. In formulations requiring high pigment addition amount, the addition amount of low content water-based color paste is forced to increase, which not only increases the production cost, but also negatively affects the stability of the formulation, and at the same time significantly changes the skin feel of the product, which cannot meet the high standard requirements of color cosmetic products on performance and use experience. SUMMARY

[0003] In order to obtain a water-based color paste with high storage stability, high solid content and narrow particle size distribution, the present application provides a hydrophobic powder water dispersion paste and a preparation method and application thereof.

[0004] The hydrophobic powder water dispersion paste provided by the present application adopts the following technical scheme: A hydrophobic powder water dispersion paste, which comprises the following components in terms of mass percentage: 50-80% of inorganic color powder, 5-20% of dispersant, 0.1-5% of polyol, 0.1-2% of preservative, and the rest is water; the inorganic color powder is subjected to surface modification treatment, and the modifier used in the surface modification treatment comprises one or a combination of two or more of amino acid, biomimetic sebum, silicon-containing treatment agent, higher fatty acid and salt thereof.

[0005] By adopting the technical scheme, the inorganic toner is surface modified by using amino acid, bionic sebum, etc., so that the surface hydrophobicity is enhanced, the agglomeration caused by the hydroxyl network is broken, and the dispersion stability of the dispersion slurry in the water-based system is improved.

[0006] Optionally, the polyhydric alcohol includes one or more than two mixtures of glycerol, butylene glycol, propylene glycol, pentylene glycol, hexylene glycol, xylitol, polypropylene glycol, and sorbitol.

[0007] By adopting the technical scheme, the polyhydric alcohol (such as glycerol and butylene glycol) defined in the application has the functions of moisturizing and dispersion assisting. The polyhydric alcohol can form a hydrogen bond network with water, reduce the surface tension of the dispersion medium, and synergistically act with the dispersant to wrap the inorganic toner particles, hinder the agglomeration of the particles, further enhance the stability of the water dispersion slurry, reduce the stratification phenomenon, and have no negative impact on the skin feel.

[0008] Optionally, the dispersant includes one or more than two mixtures of lauryl polyether-9, oleyl polyether-10, oleyl polyether-20, Tween 60, Tween 80, hydrogenated castor oil, ammonium polyacrylate, and sodium polyacrylate.

[0009] By adopting the technical scheme, the dispersant selected in the application has a suitable HLB value, can effectively reduce the interfacial tension between the inorganic toner (after hydrophobic modification) and the water-based medium, promote the uniform dispersion of the particles in the oil-in-water system, form an elastic interfacial film on the surface of the particles, resist the agglomeration of the particles, improve the stability of the dispersion slurry in the oil-in-water emulsion system, and solve the problem of uneven dispersion of the traditional product in the system.

[0010] Optionally, the inorganic toner is subjected to a three-stage gradient surface modification treatment, and the used modifier combination includes: (a) triethoxysilane and aminopropyl polydimethylsiloxane are compounded at a mass ratio of (2.5-4):1; (b) triisostearyl isopropoxy titanium salt; (c) hydrogenated lecithin and phosphatidylserine are compounded at a mass ratio of (1.5-3):1; and the mass ratio of (a):(b):(c) is (4.0-5.0):(2.0-3.0):(2.5-3.5).

[0011] By adopting the technical scheme, the three-level gradient surface modification can realize high hydrophobicity, good dispersibility and excellent skin feeling through the synergistic effect of the specific proportion of the complex modifier: (a) the silane type modifier enhances the surface hydrophobicity and water resistance; (b) the titanium salt type modifier improves the sliding property of the particles in the dispersion medium and improves the smoothness; and (c) the lecithin type modifier simulates the skin lipid and enhances the skin feeling compatibility. The optimization of the total addition amount and the proportion avoids the agglomeration caused by the excessive modifier, ensures the stability of the hydrophobic angle, and significantly improves the dispersibility and use experience of the dispersion slurry in the aqueous system.

[0012] Optionally, the specific method for the surface modification treatment of the inorganic toner is as follows: The inorganic toner is dispersed in a solvent or water to form a suspension; The modifier is added, and the addition amount of the modifier is 5%-10% of the mass of the inorganic toner; The reaction is stirred at a temperature of 40-80℃ for 1-5 hours; After the reaction is completed, the inorganic toner with a surface hydrophobic modification is obtained through separation, washing and drying.

[0013] By adopting the technical scheme, the modification method can ensure the full reaction of the modifier and the surface hydroxyl group of the inorganic toner by controlling the reaction temperature and time, so that a uniform hydrophobic layer is formed. The separation and washing steps remove the unreacted modifier impurities, so that the dispersion stability is not affected by the residual substances; and the drying treatment ensures the particle dryness, so that the secondary agglomeration is reduced.

[0014] Optionally, the inorganic toner needs to be treated as follows before the hydrophobic modification: The inorganic toner is mixed with a mesoporous silica precursor, and a mesoporous layer is coated on the surface of the toner through a sol-gel method, and the pore size is 2-20nm; the porosity of the mesoporous layer is ≥50%, and the specific surface area is >200m 2 / g.

[0015] By adopting the technical scheme, the mesoporous silica layer (pore size 2-20nm, porosity ≥50%) coated first provides a porous attachment site for the subsequent hydrophobic modification, greatly increases the combination area of the modifier and the toner, and improves the durability of the modified layer. The high specific surface area (>200m 2 / g) enhances the interaction between the particles and the dispersant, and further inhibits the agglomeration; and the mesoporous structure can also adsorb part of the dispersion medium, buffer the collision between the particles, and improve the long-term storage stability of the dispersion slurry.

[0016] In a second aspect, the application provides a preparation method of a hydrophobic powder water dispersion paste, which adopts the following technical scheme: a preparation method of a hydrophobic powder water dispersion paste, comprising the following steps: S1, adding a dispersant, a polyol and a preservative into water, stirring and dispersing uniformly to form an emulsified gel; S2, adding inorganic toner subjected to surface modification treatment into the emulsified gel, stirring and dispersing uniformly under ultrasonic vibration, and the temperature is less than 60℃, to obtain a mixed material body; S3, grinding and dispersing the mixed material body to obtain an inorganic toner water dispersion paste.

[0017] By adopting the above technical scheme, the step-by-step preparation method in the application first forms an emulsified gel, uses a dispersant and a polyol to construct a stable continuous phase network, and provides a uniform dispersion environment for the inorganic toner; low-temperature (<60℃) stirring avoids the failure of the dispersant or the thermal agglomeration of particles caused by high temperature; the grinding and dispersing step further refines the particles by mechanical force, breaks the residual agglomerates, and ensures the uniform distribution of the toner in the aqueous system, thereby guaranteeing the stability and particle size uniformity of the dispersion paste from the preparation process level.

[0018] Optionally, the S2 step is: adding the inorganic toner subjected to surface modification treatment into the emulsified gel, degassing for 5-15 minutes under a vacuum degree of-0.08 to-0.095 MPa and stirring at 200-300 rpm; after degassing is completed, the mixed material body is obtained by ultrasonic dispersion under the condition that the temperature is less than 60℃.

[0019] By adopting the above technical scheme, the dissolved gas (such as air, CO2) in the mixed material body is effectively removed under a high vacuum environment of-0.08 to-0.095 MPa, avoiding the gas bubbles from becoming an agglomeration center in the subsequent grinding or storage process, and causing the bridging phenomenon between particles. The vacuum environment reduces the surface tension of the liquid, promotes the full wetting of the dispersion medium to the inorganic toner, makes the modified layer better combined with the dispersant, and improves the dispersion efficiency. The removal of oxygen can delay the oxidative degradation of the polyol or the preservative, prolong the shelf life of the product, and is especially suitable for formula systems sensitive to oxidation. Ultrasonic vibration promotes the uniform adsorption of the dispersant on the particle surface, enhances the repulsive force between the particles, and ultrasonic dispersion is carried out under the condition that the temperature is less than 60℃, avoiding the turbidity point phenomenon of the dispersant or the detachment of the modified layer caused by high temperature, and maintaining the stability of the system.

[0020] Optionally, the particle size distribution of the inorganic toner water dispersion paste is D90<2 μm and the Span value is ≤1.2.

[0021] By adopting the technical scheme, the specific surface area and hiding power of the toner are improved by the small particle size, and the narrow distribution reduces the skin granular feeling caused by large particles, so that the dispersion paste can form a fine coating film when applied to cosmetics, improve the smoothness and uniformity of application, and reduce the sedimentation and stratification caused by particle size difference.

[0022] In a third aspect, the application provides an application of a hydrophobic powder water dispersion paste. The product obtained by the preparation method of the hydrophobic powder water dispersion paste is applied to colored face cream, bare-faced cream, sunscreen cream, lip gloss and other cosmetics.

[0023] By adopting the technical scheme, the application scenario of the application directly matches the pertinence of the technical improvement in view of the problems of poor dispersion, low stability and poor skin feeling of traditional inorganic toner in water-based or oil-in-water type cosmetics such as colored face cream and lip gloss. The hydrophobic powder water dispersion paste can maintain stable dispersion at high solid content in these products, reduce the interference of the addition amount on the formula system; the good hydrophobicity and dispersibility ensure that the product does not stratify and does not agglomerate during storage and use, while improving the smoothness and skin feeling compatibility during application, meeting the comprehensive needs of color cosmetic products for appearance, stability and use experience.

[0024] In summary, the application has the following beneficial effects: 1. By increasing the inorganic toner content to 50-80%, the application solves the problem of large addition amount of low-content toner in high-pigment-demand formula, which affects the stability and skin feeling; and by combining the synergistic effect of surface modification, dispersant and polyol, the hydrophobic powder is uniformly dispersed in water-based and oil-in-water systems, overcoming the defects of traditional dispersion paste in such systems, such as difficulty in dispersion and easy stratification, and filling the technical gap of high-solid-content water-based toner.

[0025] 2. In the application, a three-stage gradient modification combined with mesoporous silica coating is preferably adopted, which not only enhances the adhesion of the modifier through the porous structure, but also realizes the balance of hydrophobicity, dispersibility and skin feeling through the adjustment of the compounding ratio, more comprehensively solving the problems of inorganic toner agglomeration, easy detachment of the modified layer and poor use experience, and significantly improving the comprehensive performance of the product.

[0026] 3. The method of the application optimizes the process of particle size control by emulsified gel pre-dispersion, low-temperature stirring and grinding, ensures that the high-solid-content powder forms a stable dispersion paste in the water-based medium, and can be adapted to various color cosmetic formulations such as colored face cream and lip gloss. This process breaks through the limitations of traditional methods in particle size control and system compatibility, so that the hydrophobic powder water dispersion paste exhibits excellent stability and use performance in the oil-in-water system, and widens the application boundary of inorganic pigments in the field of cosmetics. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a sample appearance diagram of Example 1 of the present application; Figure 2 is a sample appearance diagram of Comparative Example 1 of the present application; Figure 3 is a micrograph of the sample of Example 1 of the present application smeared on the skin; Figure 4 is a micrograph of the sample of Comparative Example 1 of the present application smeared on the skin. DETAILED DESCRIPTION

[0028] The present application is further described in detail below with reference to Examples, with the proviso that: the specific conditions are not specified in the following examples, the conventional conditions or the conditions recommended by the manufacturer are adopted, and the raw materials used in the following examples can be sourced from ordinary commercial markets unless otherwise specified. EXAMPLE

[0029] Example 1 A method for preparing a hydrophobic powder water dispersion paste: (1) Preparation of raw materials: Inorganic color powder: iron oxide red (average particle size 1 μm) is selected as a common colorant for makeup; Modifier: triethoxysilane, analytical pure, is selected. Dispersing agent: Tween 80. Polyhydric alcohol: propylene glycol. Preservative: phenoxyethanol. Deionized water: as a dispersion medium. (2) Surface hydrophobic treatment of inorganic color powder Take 100 g of iron oxide red, disperse it in isopropyl alcohol to form a 50% solid content suspension. Add 10 g of modifier, stir and react at 60°C for 3 hours. After the reaction is completed, centrifugal separation is performed, and isopropyl alcohol is used for washing twice, and vacuum drying at 60°C for 3 hours to obtain surface hydrophobic modified iron oxide red. (3) Preparation of hydrophobic powder water dispersion paste S1, emulsion gel preparation: 12.5 g of dispersing agent Tween 80, 2.55 g of polyhydric alcohol propylene glycol, and 1.05 g of preservative phenoxyethanol are added to 18.9 g of deionized water, and stirred at 40°C for 30 minutes to form a uniform emulsion gel.

[0030] S2, mixed dispersion: 65 g of surface modified iron oxide red is slowly added to the emulsion gel, and ultrasonic mixing and stirring is performed at 50°C for 1 hour to form a uniform mixed material. S3, grinding dispersion: the mixed material is transferred into a three-roll mill, and repeatedly ground for three times to obtain a hydrophobic powder water dispersion paste.

[0031] Example 2 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the added raw materials are inorganic toner 50 g, dispersant 5 g, polyol 0.1 g, preservative 0.1 g, and water 44.8 g.

[0032] Example 3 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the added raw materials are inorganic toner 80 g, dispersant 10 g, polyol 3 g, preservative 1.5 g, and water 5.5 g.

[0033] Example 4 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is glycerol.

[0034] Example 5 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is butanediol.

[0035] Example 6 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is pentanediol.

[0036] Example 7 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is hexanediol.

[0037] Example 8 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is xylitol.

[0038] Example 9 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is polypropylene glycol.

[0039] Example 10 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is sorbitol.

[0040] Example 11 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is a mixture of glycerol, butanediol, propylene glycol, and pentanediol in a mass ratio of 1:1:1:1.

[0041] Example 12 A method for preparing a hydrophobic powder water dispersion paste, which is different from Example 1 in that the polyol is a mixture of hexanediol, xylitol, polypropylene glycol, and sorbitol in a mass ratio of 1:1:1:1.

[0042] Example 13 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be sodium stearoyl glutamate.

[0043] Example 14 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be phosphatidylserine.

[0044] Example 15 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be lauric acid.

[0045] Example 16 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be lauric acid and sodium stearoyl glutamate compounded in a mass ratio of 1:1.

[0046] Example 17 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be phosphatidylserine, aminopropyl polydimethylsiloxane, sodium myristoyl glutamate, and jojoba seed oil compounded in a mass ratio of 1:1:1:1.

[0047] Example 18 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the modifier is selected to be: (a) triethoxyl octyl silane and aminopropyl polydimethylsiloxane compounded in a mass ratio of 3.5:1; (b) triisostearyl isopropoxy titanium salt; (c) hydrogenated lecithin and phosphatidylserine compounded in a mass ratio of 2.2:1; and the mass ratio of (a):(b):(c) is 4.5:2.5:3.

[0048] Example 19 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the mass ratio of (a):(b):(c) in the modifier is 4:3:2.5.

[0049] Example 20 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the mass ratio of (a):(b):(c) in the modifier is 5:2:3.5.

[0050] Example 21 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the triethoxyl octyl silane and aminopropyl polydimethylsiloxane in the modifier are compounded in a mass ratio of 2.5:1.

[0051] Example 22 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the modifier is compounded by (a) triethoxyl octyl silane and amino propyl polydimethyl siloxane with a mass ratio of 4:1.

[0052] Example 23 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the modifier is compounded by (c) hydrogenated lecithin and phosphatidyl serine with a mass ratio of 1.5:1.

[0053] Example 24 A method for preparing a hydrophobic powder water dispersion slurry: different from example 18 is that the modifier is compounded by (c) hydrogenated lecithin and phosphatidyl serine with a mass ratio of 3:1.

[0054] Example 25 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the inorganic toner needs to be treated as follows before hydrophobic modification: Mix 100g red iron oxide with 20g tetraethyl orthosilicate, add ethanol-water mixed solvent (volume ratio 1:1), and stir to form a suspension. Add dilute hydrochloric acid dropwise to the suspension to adjust the pH to 3.5, and open a constant temperature water bath to stabilize the system temperature at 60°C (temperature difference controlled within ±1°C), while starting the stirrer to continuously stir at a speed of 300r / min. Under the conditions of acid and 60°C heat drive, the tetraethyl orthosilicate gradually undergoes hydrolysis reaction to generate silicic acid monomer (Si(OH)4), which gradually polymerizes into nano-sized silica sol particles through condensation reaction between hydroxyl groups to form Si-O-Si covalent bonds, and these particles are combined with the surface of red iron oxide by electrostatic adsorption to begin forming an initial coating layer on the surface of the toner. At this time, the viscosity of the suspension increases significantly, and the vortex produced by stirring becomes shallower. Continue the reaction for 120min to obtain a suspension of red iron oxide coated with mesoporous silica. After the reaction is completed, centrifugal separation is performed, and the product is washed with ethanol 3 times and vacuum dried at 80°C for 4 hours to obtain red iron oxide coated with a mesoporous layer. The mesoporous layer has a pore size of 10-15nm, a porosity of 60%, and a specific surface area of 250m 2 / g.

[0055] Example 26 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the dispersant is lauryl polyether-9.

[0056] Example 27 A method for preparing a hydrophobic powder water dispersion slurry: different from example 1 is that the dispersant is oleyl polyether-20.

[0057] Example 28 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that the dispersant is selected from hydrogenated castor oil and ammonium polyacrylate with a mass ratio of 1:1.

[0058] Example 29 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that the dispersant is selected from oleyl polyether-10, Tween 60, and sodium polyacrylate with a mass ratio of 1:1:1.

[0059] Example 30 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that step S2 is as follows: A planetary mixer with a vacuum system is used, equipped with an anchor stirring paddle, and the vacuum gauge is pre-calibrated to ensure a measurement error of ≤±0.002 MPa.

[0060] The emulsified gel is transferred to the mixer cylinder, the jacket cooling water circulation is turned on, and the temperature in the cylinder is maintained at ≤40℃. Under low-speed stirring at 200 rpm, the hydrophobically modified inorganic toner is slowly added, the vacuum pump is started, and the vacuum degree in the cylinder is extracted to -0.08 MPa. The stirring speed is maintained at 250 rpm, and the vacuum degree is maintained in the range of -0.08 to -0.085 MPa for 10 minutes of degassing. After degassing is completed, nitrogen is slowly introduced to break the vacuum (inlet gas rate ≤10 L / min) to avoid material splashing. The material is transferred to an ultrasonic dispersion device (model: JY92-IIN, 20 kHz, 1000 W), the ultrasonic probe is set to be immersed to a depth of 3 cm below the liquid surface to ensure uniform radiation. The pulse mode is used: ultrasonic working for 3 seconds, intermittent for 2 seconds (duty cycle 60%), power density 0.8 W / mL, and the material temperature is maintained at ≤55℃ (real-time monitoring). After 5 minutes of ultrasonic treatment, the mixed material is obtained.

[0061] Comparative Example Comparative Example 1 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that the inorganic toner is not subjected to surface hydrophobic modification treatment.

[0062] Comparative Example 2 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that the inorganic toner is 30g, the dispersant is 21g, the polyol is 6g, the preservative is 3g, and the water is 40g.

[0063] Comparative Example 3 A method for preparing a hydrophobic powder water dispersion paste, which is different from example 1 in that the inorganic toner is 90g, the dispersant is 4g, the polyol is 0.5g, the preservative is 0.5g, and the water is 5g.

[0064] Performance test Detection method 1. Absorbance test Since the titanium dioxide is dispersed in water, the titanium dioxide will be dispersed into the water phase to form a white opaque dispersion liquid which will absorb light. Therefore, the absorbance of the colorant water dispersion liquid is used to qualitatively represent the content of titanium dioxide contained in the dispersion liquid. The greater the absorbance, the better the dispersion of the colorant.

[0065] Test process: 1 g of colorant of examples 1-29 and comparative examples 1-3 was weighed and dispersed in 50 ml of water. After standing for 10 min, 1 ml of dispersion liquid 1 cm away from the liquid surface was taken and diluted 100 times. Then, the absorbance of the three diluted liquids was tested using a 722N spectrophotometer.

[0066] 2. Particle size and stability test Particle size test method: 0.1 g of samples of examples 1-29 and comparative examples 1-3 was weighed and dispersed in 50 g of pure water. Then, the particle size was detected using a laser particle size instrument 2600E. Stability test method: stability comparison test was performed on examples 1-29 and comparative examples 1-3. Cold resistance test was performed at a temperature of -18℃, heat resistance test was performed at 50℃, and cold-heat cycle was performed at -18℃ and 50℃. The appearance change was observed for one month, and particle size and stability test was performed.

[0067] Table 1 detection data It can be seen from examples 1 and comparative examples 1 and table 1 that the absorbance of example 1 after surface hydrophobic modification is 0.54, which is significantly higher than that of comparative example 1 (0.16), and D90 (1.1 μm) and span value (0.85) are much smaller than those of comparative example 1 (3.5 μm, 2.10). In the stability test, example 1 has no change under cold-heat cycle, while comparative example 1 has serious aggregation and stratification, indicating that surface hydrophobic modification of inorganic colorant is the key to solve the aggregation in water-based system, improve the dispersion and stability, effectively break the aggregation caused by hydroxyl network, and enhance the compatibility with water-based medium. It can be seen from the combination of Example 1 and Comparative Examples 2-3 and Table 1 that the absorbance of inorganic toner 65% and dispersant 12.5% in Example 1 is 0.54, D90 is 1.1 μm, and the stability is excellent; the absorbance of Comparative Example 2 (toner 30%, dispersant 21%) is only 0.32, and there is a problem of adhesion and stratification; the absorbance of Comparative Example 3 (toner 90%, dispersant 4%) is 0.22, and there is a serious problem of agglomeration, which shows that when the components are within the scope of the application, stable dispersion can be achieved at high solid content, and deviation from the scope will lead to decreased dispersibility and stability due to insufficient or excessive dispersant, verifying the rationality of the component ratio of the application.

[0068] It can be seen from the combination of Examples 1-3 and Table 1 that the absorbance of Example 1 (65% toner), Example 2 (50% toner), and Example 3 (80% toner) is 0.54, 0.49, and 0.52, respectively, D90 is less than 1.3 μm, and Span value is ≤0.90, and the stability is good overall (only Example 2 has a slight stratification after cold and hot cycles), which shows that inorganic toner can be prepared into high-performance water dispersion paste within the range of 50-80%, and the content of about 65% performs better in the balance between dispersibility and stability, further proving the feasibility of the high solid content formula. It can be seen from the combination of Examples 1, 4-12 and Table 1 that the absorbance of a single polyol (such as propylene glycol, glycerol) is between 0.51-0.53, while the absorbance of Example 11 (glycerol + butylene glycol, etc.) is 0.56, and the stability does not change, which shows that the synergistic effect of the hydrogen bond network can be enhanced by compounding polyols, which can more effectively reduce the interfacial tension and improve the wettability of the dispersing medium to the hydrophobic powder, thereby optimizing the dispersibility and stability of the dispersion paste. It can be seen from the combination of Examples 1, 13-18 and Table 1 that the absorbance of Example 1 (single silane modifier) is 0.54, while the absorbance of Examples 13-18 using a composite modifier is 0.61 in Example 18 (tertiary gradient modification), D90 is 0.8 μm, which is significantly better than the single modifier (such as 0.49 in Example 13), which shows that the type of modifier has a significant impact on performance, and the compounding of amino acid, biomimetic sebum, and silane can enhance hydrophobicity and improve skin feel through synergistic effect, and the tertiary gradient modification system has the best dispersion effect due to its hydrophobicity, slipperiness, and compatibility. It can be seen from Examples 1, 18-24 and Table 1 that the absorbance of Example 18 (modifier ratio 4.5:2.5:3) is 0.61, D90 is 0.8 pm, and Span is 0.65, which is better than other ratio combinations (such as 0.59 of Example 19 and 0.55 of Example 24), and the effect is better when the ratio of (a) group silane is 2.5-4:1 and (c) group lecithin is 1.5-3:1, indicating that the modifier compound ratio needs to be accurately controlled, the synergistic effect of silane providing hydrophobicity, titanium salt enhancing sliding property, and lecithin improving compatibility can be maximized at a specific ratio, and deviation from the optimal ratio will lead to performance degradation. It can be seen from Examples 1, 25 and Table 1 that after coating a mesoporous silica layer before modification, the absorbance of Example 25 is increased from 0.54 of Example 1 to 0.60, the D90 is reduced from 1.1 pm to 0.6 pm, and the Span value is reduced from 0.85 to 0.55, and the stability is unchanged, indicating that the mesoporous layer (pore size 2-20 nm, porosity ≥50%) greatly increases the binding area of the modifier and the powder by providing porous attachment sites, enhances the durability of the modified layer, and at the same time, the high specific surface area promotes the adsorption of the dispersant, further inhibits agglomeration, and significantly improves the comprehensive performance of the dispersion slurry. It can be seen from Examples 1, 26-29 and Table 1 that the absorbance of Example 1 (Tween 80) is 0.54, while the absorbance of Example 28 (hydrogenated castor oil + ammonium polyacrylate) and Example 29 (oleyl polyether-10 + Tween 60, etc.) using compound dispersants reaches 0.54-0.56, and the D90 is smaller (1.05-1.1 pm), and the stability is better, indicating that the dispersant can optimize the HLB value by compounding to enhance the adaptability to the hydrophobic modified powder, form a more stable interface film, and thus improve the dispersion uniformity and anti-agglomeration ability of the dispersion slurry. It can be seen from Examples 1, 30 and Table 1 that by using the vacuum degassing (-0.08 to -0.085 MPa) + ultrasonic dispersion process, the absorbance of Example 30 is increased from 0.54 of Example 1 to 0.59, the D90 is reduced from 1.1 pm to 0.7 pm, the Span value is reduced from 0.85 to 0.60, and the stability is unchanged, indicating that optimizing the preparation process can effectively remove bubbles in the mixed material, avoid bubbles from becoming agglomeration centers, and at the same time, ultrasonic vibration promotes uniform adsorption of the dispersant, further refines the particle size, and improves the dispersibility and stability of the dispersion slurry from the process level. This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. Those skilled in the art can make modifications to the present embodiment without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the Patent Law.

Claims

1. A hydrophobic powder water dispersion slurry, characterized by, The composition includes the following components by mass percentage: Inorganic toner 50-80%, dispersant 5-20%, polyol 0.1-5%, preservative 0.1-2%, and the rest is water; the inorganic toner is subjected to surface modification treatment, and the modifier used in the surface modification treatment includes one or a combination of two or more of amino acid, biomimetic sebum, silicon-containing treatment agent, and higher fatty acid and its salt.

2. The hydrophobic powder water dispersion slurry according to claim 1, characterized by: The polyol includes one or a mixture of two or more of glycerol, butanediol, propylene glycol, pentanediol, hexanediol, xylitol, polypropylene glycol, and sorbitol.

3. The hydrophobic powder water dispersion slurry according to claim 1, characterized by: The dispersant includes one or a mixture of two or more of lauryl polyether-9, oleyl polyether-10, oleyl polyether-20, Tween 60, Tween 80, hydrogenated castor oil, ammonium polyacrylate, and sodium polyacrylate.

4. The hydrophobic powder water dispersion slurry according to claim 1, characterized by: The inorganic toner is subjected to three-stage gradient surface modification treatment, and the modifier combination includes: (a) triethoxysilane and aminopropyl polydimethylsiloxane in a mass ratio of (2.5-4):1; (b) triisostearyl isopropoxy titanium salt; (c) hydrogenated lecithin and phosphatidylserine in a mass ratio of (1.5-3):1; and the mass ratio of (a):(b):(c) is (4.0-5.0):(2.0-3.0):(2.5-3.5).

5. The hydrophobic powder water dispersion slurry according to claim 1, characterized by: The specific method for surface modification treatment of the inorganic toner is: dispersing the inorganic toner in a solvent or water to form a suspension; adding a modifier, and the addition amount of the modifier is 5%-10% of the mass of the inorganic toner; stirring and reacting at a temperature of 40-80°C for 1-5 hours; after the reaction is completed, separating, washing, and drying to obtain the inorganic toner with hydrophobic surface modification.

6. The hydrophobic powder water dispersion slurry according to claim 1, characterized by: The inorganic toner also needs to be subjected to the following treatment before hydrophobic modification: mixing the inorganic toner with a mesoporous silica precursor, coating a mesoporous layer on the surface of the toner by sol-gel method, and the pore size is 2-20 nm; the porosity of the mesoporous layer is ≥50%, and the specific surface area is >200 m² / g.

7. A process for the preparation of a hydrophobic powder water dispersion slurry according to any one of claims 1 to 6, characterized in that: including the following steps: S1, adding a dispersant, a polyol, and a preservative into water, stirring and dispersing uniformly to form an emulsified gel; S2, adding the inorganic toner subjected to surface modification treatment into the emulsified gel, stirring and dispersing uniformly under ultrasonic, and the temperature is <60°C to obtain a mixed material; S3, grinding and dispersing the mixed material to obtain an inorganic toner water dispersion paste.

8. The method for preparing hydrophobic powder aqueous dispersion slurry according to claim 1, characterized in that: The S2 step is: adding the inorganic toner subjected to surface modification treatment into the emulsified gel, degassing for 5-15 minutes under a vacuum degree of -0.08~-0.095 MPa and stirring at 200-300 rpm; after degassing is completed, the mixed material is obtained by ultrasonic dispersion under a temperature of <60°C.

9. The method for preparing hydrophobic powder aqueous dispersion slurry according to claim 1, characterized in that: The particle size distribution of the inorganic toner water dispersion paste is D90<2 μm and the Span value is ≤1.

2.

10. The product obtained by the preparation method of the hydrophobic powder water dispersion paste according to any one of claims 1-6 or the hydrophobic powder water dispersion paste according to any one of claims 7-9 is applied to colored face cream, bare-faced cream, sunscreen cream, lip gloss, and other cosmetics.

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