Modified sericite powder, preparation method and application thereof
By combining high-temperature calcination and surface activation treatment with drying using volatile solvents, the problem of poor modification effect of sericite powder was solved, uniform coating of modifier was achieved, the skin feel and hydrophobicity of sericite powder were improved, and the preparation process was simplified.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI CO FUN BIOTECH
- Filing Date
- 2023-06-29
- Publication Date
- 2026-07-07
AI Technical Summary
In traditional surface modification methods, sericite powder does not readily adsorb modifiers, resulting in poor modification effects. Furthermore, the preparation process is complex, making it difficult to guarantee the skin feel and hydrophobicity of sericite powder.
Modified sericite powder is prepared by high-temperature calcination and pre-activation with strong acid or strong alkali, followed by mixing and drying with a volatile solvent with a surface tension of less than or equal to 25 mN/m, and then mixing with a modifier.
The modifier is uniformly coated on the surface of sericite powder, which improves its skin feel and hydrophobicity, and the preparation process is simple.
Smart Images
Figure BDA0004313706260000121 
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Figure BDA0004313706260000141
Abstract
Description
Technical Field
[0001] This invention relates to the field of cosmetic technology, and in particular to a modified sericite powder, its preparation method, and its application. Background Technology
[0002] Mica is a widely used base material in color cosmetics and base makeup products. Sericite, a natural fine-grained white mica, is translucent with a silky sheen. It possesses a unique high aspect ratio and excellent UV shielding properties, especially its fine flaky layer structure, which gives it a soft and smooth texture. Therefore, sericite powder has excellent properties such as a fine, smooth feel, stable chemical properties, strong adhesion, good dispersibility, uniform mixing with water and glycerin, silky sheen, and UV protection, making it a high-quality raw material for various cosmetics.
[0003] However, sericite powder, used as a pigment in cosmetics, is prone to agglomeration due to its small particle size, large specific surface area, and increased interparticle contact points. Therefore, it needs to undergo surface modification to improve its poor dispersibility. In traditional surface modification methods, sericite powder does not easily adsorb modifiers, resulting in insufficient contact between the powder and the modifier, poor modification effect, and inability to guarantee the skin feel and hydrophobicity of sericite powder. At the same time, the preparation process of coating sericite powder with modifiers in traditional technology is complex. Summary of the Invention
[0004] Therefore, it is necessary to provide a modified sericite powder, its preparation method, and its application to address the above problems. This preparation method can uniformly coat the sericite powder particles with modifiers, giving the modified sericite powder excellent skin feel and hydrophobicity, and the preparation process is simple.
[0005] A method for preparing modified sericite powder includes the following steps:
[0006] Provides sericite powder;
[0007] The sericite powder is pre-activated to obtain pre-activated sericite powder, wherein the pre-activation method is selected from method (a) and / or method (b), method (a) calcining the sericite powder, and method (b) acidifying the sericite powder with a strong acid at pH ≤ 4 or alkalizing the sericite powder with a strong alkali at pH ≥ 11.
[0008] The pre-activated sericite powder is mixed with a volatile solvent and then dried to obtain pretreated sericite powder, wherein the surface tension of the volatile solvent is less than or equal to 25 mN / m.
[0009] The pretreated sericite powder was mixed with a modifier and modified to obtain modified sericite powder.
[0010] In one embodiment, the calcination temperature of the sericite powder is 300℃-500℃ and the calcination time is 3h-6h.
[0011] In one embodiment, in the step of acidifying the sericite powder with a strong acid under conditions of pH ≤ 4, the acidification time is 0.5h-4h.
[0012] Alternatively, in the step of alkalizing the sericite powder with a strong alkali under conditions of pH ≥ 11, the alkalization time is 0.5h-4h.
[0013] In one embodiment, the strong acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, perchloric acid, permanganic acid, hydrobromic acid, and hydroiodic acid; the strong base is selected from at least one of sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, calcium hydroxide, barium hydroxide, and strontium hydroxide.
[0014] In one embodiment, the surface tension of the volatile solvent is 15 mN / m to 25 mN / m.
[0015] In one embodiment, the volatile solvent is selected from at least one of isododecane, n-hexane, ethanol, isopropanol, low-viscosity silicone oil, and cyclopentamethoxysiloxane.
[0016] In one embodiment, in the step of drying the pre-activated sericite powder after mixing it with a volatile solvent, the mass ratio of the volatile solvent to the pre-activated sericite powder is 3:100-15:100, the drying temperature is 80℃-150℃, and the drying time is 1h-4h.
[0017] In one embodiment, the modifier is selected from at least one of hydrogenated polydimethylsiloxane, polydimethylsiloxane, triethoxyoctylsilane, and amino-modified silicone oil;
[0018] And / or, in the step of mixing the pretreated sericite powder with a modifier for modification treatment, the mass ratio of the modifier to the pretreated sericite powder is 1:100-10:100.
[0019] A modified sericite powder is prepared by the method described above.
[0020] An application of the modified sericite powder described above in cosmetics.
[0021] In the preparation method of modified sericite powder provided by the present invention, the powder is first pre-activated by high-temperature calcination, strong acidification, or strong alkali alkali treatment, which increases the defect sites on the surface of the sericite powder and improves the disadvantage of the sericite powder surface being easily hydrated, so that the sericite powder can be more fully combined and adsorbed with the modifier. Secondly, after the pre-activated sericite powder is mixed with a volatile solvent with a specific tension, the volatile solvent can continuously enter the interlayer of the powder. During drying, the volatile solvent evaporates and expands due to heat, effectively expanding the pore channels between the layers of sericite powder, providing a channel for the entry of the modifier. Moreover, the volatile solvent can pre-wet the inner and outer surfaces of the powder, which is more conducive to the subsequent coating and modification of the modifier.
[0022] Therefore, by pre-activating and pre-treating the sericite powder, the modifier can be uniformly and completely coated on the surface of the sericite powder particles, reducing the frictional resistance between the layers in the powder particles. As a result, the modified sericite powder has excellent skin feel and hydrophobicity, and the preparation process is simple. Attached Figure Description
[0023] Figure 1 The images show the contact angle test results of the modified sericite powders obtained in Examples 1, 2, 3 and Comparative Example 3, where (a) is the modified sericite powder obtained in Example 1, (b) is the modified sericite powder obtained in Example 2, (c) is the modified sericite powder obtained in Example 3, and (d) is the modified sericite powder obtained in Comparative Example 3. Detailed Implementation
[0024] To facilitate understanding of the present invention, a more complete description will be given below with reference to relevant embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.
[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0026] This invention provides a method for preparing modified sericite powder, comprising the following steps:
[0027] S1 provides sericite powder;
[0028] S2, the sericite powder is pre-activated to obtain pre-activated sericite powder, wherein the pre-activation method is selected from method (a) and / or method (b), method (a) calcining the sericite powder, and method (b) acidifying the sericite powder with a strong acid at pH ≤ 4 or alkalizing the sericite powder with a strong alkali at pH ≥ 11.
[0029] S3, the pre-activated sericite powder is mixed with a volatile solvent and then dried to obtain pretreated sericite powder, wherein the surface tension of the volatile solvent is less than or equal to 25 mN / m;
[0030] S4, the pretreated sericite powder is mixed with a modifier and modified to obtain modified sericite powder.
[0031] In step S1, sericite has a 2:1 layered silicate structure, consisting of two layers of silicon-oxygen tetrahedra and a middle layer of silicon-oxygen octahedra. The apical oxygen of the tetrahedra and the additional anion (OH-) - The active water-crystallization group is located between two silicon-oxygen tetrahedral layers, forming a triple thin layer with a thickness of 10 Å. The high potassium ions between the thin layers are loosely bonded together, making it easy to split into extremely thin sheets with a large planar area. It is also very easy to hydrate and cannot fully contact the oleophilic modifier. Therefore, it needs to undergo subsequent pre-activation and pretreatment to ensure that the sericite powder can fully contact and react with the modifier.
[0032] To facilitate subsequent processing of sericite powder, in one embodiment, the particle size of the sericite powder is preferably 100nm-20000nm.
[0033] In step S2, pre-activation treatments such as high-temperature calcination, strong acid acidification, or strong alkali alkali treatment can increase the defect sites on the surface of sericite powder and improve the disadvantage of the sericite powder surface being easily hydrated, thereby enabling the sericite powder to combine and adsorb more fully with the modifier.
[0034] In one embodiment, the strong acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, perchloric acid, permanganic acid, hydrobromic acid, and hydroiodic acid; the strong base is selected from at least one of sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, calcium hydroxide, barium hydroxide, and strontium hydroxide.
[0035] It is understood that the pre-activation treatment can be selected from method (a) or method (b) alone, or it can be performed by both methods (a) and (b). When performing the pre-activation treatment, there is no restriction on the order of methods (a) and (b).
[0036] When the pre-activation treatment method is selected from method (a), in order to better pre-activate the sericite powder, in one embodiment, the calcination temperature of the sericite powder is 300℃-500℃ and the calcination time is 3h-6h. Preferably, the heating rate during calcination is 3℃ / min-10℃ / min.
[0037] When the pre-activation treatment method is selected from method (b), in order to better pre-activate the sericite powder, in one embodiment, in the step of acidifying the sericite powder with a strong acid under the condition of pH ≤ 4, the acidification time is 0.5h-4h; or, in the step of alkalizing the sericite powder with a strong alkali under the condition of pH ≥ 11, the alkalization time is 0.5h-4h.
[0038] In step S3, during the mixing of a volatile solvent with a surface tension of less than or equal to 25 mN / m with the pre-activated sericite powder, on the one hand, the volatile solvent continuously penetrates into the interlayer of the pre-activated sericite powder. Then, during the drying process, the volatile solvent evaporates and expands, which can effectively expand the void channels between the layers of the pre-activated sericite powder, providing channels for the subsequent entry of the modifier. On the other hand, the volatile solvent can wet the surface of the pre-activated sericite powder, thereby facilitating the subsequent coating and modification of the sericite powder by the modifier.
[0039] Preferably, the surface tension of the volatile solvent is 15mN / m-25mN / m.
[0040] In one embodiment, the volatile solvent is selected from at least one of isododecane, n-hexane, ethanol, isopropanol, low-viscosity silicone oil, and cyclopentamethoxysiloxane.
[0041] To better process the pre-activated sericite powder, in one embodiment, the mass ratio of the volatile solvent to the pre-activated sericite powder is 3:100-15:100.
[0042] In order to make the pre-activated sericite powder more fully contacted with the volatile solvent, in one embodiment, the pretreated sericite powder and the modifier are preferably mixed by stirring, with a stirring speed of 1000 r / min-25000 r / min.
[0043] In order to better facilitate the vaporization and expansion of the volatile solvent, in one embodiment, the drying method is preferably hot drying, with a drying temperature of 80℃-150℃ and a drying time of 1h-4h.
[0044] After pretreating the sericite powder through steps S2 and S3, in step S4, the modifier can be uniformly and completely coated on the surface of the pretreated sericite powder, reducing the frictional resistance between the layers of sericite powder, and making the obtained modified sericite powder exhibit excellent smoothness and skin feel.
[0045] Preferably, the modifier is selected from at least one of hydrogenated polydimethylsiloxane, polydimethylsiloxane, triethoxyoctylsilane, and amino-modified silicone oil.
[0046] In order to better modify the pretreated sericite powder, in one embodiment, in the step of mixing the pretreated sericite powder with a modifier for modification treatment, the mass ratio of the modifier to the pretreated sericite powder is 1:100-10:100.
[0047] In order to make the pretreated sericite powder and the modifier more fully contact, in one embodiment, the preactivated sericite powder and the volatile solvent are preferably mixed by stirring at a speed of 1000 r / min to 25000 r / min, and then allowed to stand for 0.5 h to 2 h to make the reaction more complete.
[0048] It should be noted that, in order to obtain modified sericite powder better, after the step of mixing the pretreated sericite powder with the modifier for modification treatment, a drying step is also included. The drying method is preferably hot drying, with a drying temperature of 80℃-150℃ and a drying time of 1h-4h.
[0049] The present invention also provides a method for preparing modified sericite powder as described above, which has excellent skin feel and hydrophobicity, and the preparation process is simple.
[0050] The present invention also provides an application of the modified sericite powder as described above in cosmetics. When applied to cosmetics, it can fully exert the superior properties required by cosmetics, such as skin feel, spreadability, adhesion, coverage, ultraviolet scattering effect, optical properties, and transparency.
[0051] The modified sericite powder, its preparation method, and its application will be further explained below through specific embodiments.
[0052] Example 1
[0053] We provide 100g of sericite powder with a particle size of 5000nm.
[0054] The above-mentioned sericite powder was placed in a crucible, and then the crucible was placed in a muffle furnace for high-temperature calcination for pre-activation treatment. The calcination temperature was 400℃, the calcination time was 3h, and the heating rate during calcination was 10℃ / min. After calcination, pre-activated sericite powder was obtained.
[0055] The pre-activated sericite powder obtained above was placed in a high-speed mixer. Then, 5g of n-hexane with a surface tension of 18.3mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 20000r / min for 15s. After stirring, the mixture was allowed to stand for 30min. Then, the stirred mixture was placed in an oven at 80℃ and dried for 3h. After cooling, the pretreated sericite powder was obtained.
[0056] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, a mixture of 3g of triethoxyoctylsilane and polydimethylsiloxane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 20,000 r / min for 15s. After stirring, the mixture was placed in an oven at 105℃ and dried for 2h. After cooling, modified sericite powder was obtained.
[0057] Example 2
[0058] We provide 100g of sericite powder with a particle size of 10000nm.
[0059] The above sericite powder was mixed with water to obtain an aqueous solution of sericite powder. Then, sodium hydroxide was used to adjust the pH of the aqueous solution of sericite powder to 12. The mixture was stirred for 4 hours. After stirring, the mixture was filtered, the solid was collected, and the solid was washed with water until neutral to obtain pre-activated sericite powder.
[0060] The pre-activated sericite powder obtained above was placed in a high-speed mixer. Then, 10g of a 95% ethanol aqueous solution with a surface tension of 23.2mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 15000r / min for 30s. After stirring, the mixture was allowed to stand for 1h. Then, the stirred mixture was placed in an oven at 100℃ and heated and dried for 2h. After cooling, the pretreated sericite powder was obtained.
[0061] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, 2g of polydimethylsiloxane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 15000r / min for 30s. After stirring, the mixture was placed in an oven at 120℃ and dried for 2h. After cooling, modified sericite powder was obtained.
[0062] Example 3
[0063] We provide 100g of sericite powder with a particle size of 15000nm.
[0064] The above sericite powder was mixed with water to obtain an aqueous solution of sericite powder. Then, the pH of the aqueous solution of sericite powder was adjusted to 4 with hydrochloric acid. The mixture was stirred for 3 hours. After stirring, the mixture was filtered, the solid was collected, and the solid was washed with water until neutral to obtain pre-activated sericite powder.
[0065] The pre-activated sericite powder obtained above was placed in a high-speed mixer. Then, 3g of cyclopentamethoxysiloxane with a surface tension of 20.6mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 15000r / min for 30s. After stirring, the mixture was allowed to stand for 1h. Then, the stirred mixture was placed in an oven at 100℃ and dried for 2h. After cooling, the pretreated sericite powder was obtained.
[0066] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, 2g of polydimethylsiloxane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 15000r / min for 30s. After stirring, the mixture was placed in an oven at 120℃ and dried for 2h. After cooling, modified sericite powder was obtained.
[0067] Example 4
[0068] We provide 100g of sericite powder with a particle size of 100nm.
[0069] The above-mentioned sericite powder was placed in a crucible, and then the crucible was placed in a muffle furnace for high-temperature calcination for pre-activation treatment. The calcination temperature was 300℃, the calcination time was 3h, and the heating rate during calcination was 3℃ / min. After calcination, pre-activated sericite powder was obtained.
[0070] The pre-activated sericite powder obtained above was placed in a high-speed mixer. Then, 3g of dimethyl silicone oil with a surface tension of 15.6mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 1000r / min for 15s. After stirring, the mixture was allowed to stand for 30min. Then, the stirred mixture was placed in an oven at 80℃ and dried for 1h. After cooling, the pretreated sericite powder was obtained.
[0071] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, 10g of triethoxyoctylsilane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 1000r / min for 15s. After stirring, the mixture was placed in an oven at 80℃ and dried for 1h. After cooling, modified sericite powder was obtained.
[0072] Example 5
[0073] We provide 100g of sericite powder with a particle size of 20,000nm.
[0074] The above-mentioned sericite powder was placed in a crucible, and then the crucible was placed in a muffle furnace for high-temperature calcination for pre-activation treatment. The calcination temperature was 500℃, the calcination time was 6h, and the heating rate during calcination was 10℃ / min. After calcination, pre-activated sericite powder was obtained.
[0075] The pre-activated sericite powder obtained above was placed in a high-speed mixer. Then, 15g of isododecane with a surface tension of 23.5mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 25000r / min for 15s. After stirring, the mixture was allowed to stand for 2h. Then, the stirred mixture was placed in an oven at 150℃ and dried for 4h. After cooling, the pretreated sericite powder was obtained.
[0076] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, 1g of triethoxyoctylsilane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 25000r / min for 15s. After stirring, the mixture was placed in an oven at 150℃ and dried for 4h. After cooling, modified sericite powder was obtained.
[0077] Example 6
[0078] Example 6 was carried out in accordance with Example 2, except that: the above sericite powder was mixed with water to obtain an aqueous solution of sericite powder, and then the pH of the aqueous solution of sericite powder was adjusted to 11 with potassium hydroxide. The mixture was stirred for 4 hours, filtered after stirring, the solid was collected and washed with water until neutral to obtain pre-activated sericite powder.
[0079] Example 7
[0080] Example 7 was carried out in accordance with Example 3, except that: the above sericite powder was mixed with water to obtain an aqueous solution of sericite powder, and then the pH of the aqueous solution of sericite powder was adjusted to 2 with sulfuric acid. The mixture was stirred for 3 hours, filtered after stirring, the solid was collected and washed with water until neutral to obtain pre-activated sericite powder.
[0081] Comparative Example 1
[0082] We provide 100g of sericite powder with a particle size of 5000nm.
[0083] The above sericite powder was placed in a high-speed mixer. Then, 5g of isododecane with a surface tension of 23.5mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 20000r / min for 15s. After stirring, the mixture was allowed to stand for 1h. Then, the stirred mixture was placed in an oven at 80℃ and heated and dried for 3h. After cooling, the pretreated sericite powder was obtained.
[0084] The pretreated sericite powder obtained above was placed in a high-speed mixer. Then, 3g of triethoxyoctylsilane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 20,000 r / min for 15s. After stirring, the mixture was placed in an oven at 105℃ and dried for 2h. After cooling, modified sericite powder was obtained.
[0085] Comparative Example 2
[0086] We provide 100g of sericite powder with a particle size of 10000nm.
[0087] The above sericite powder was mixed with water to obtain an aqueous solution of sericite powder. Then, sodium hydroxide was used to adjust the pH of the aqueous solution of sericite powder to 12. The mixture was stirred for 4 hours. After stirring, the mixture was filtered, the solid was collected, and the solid was washed with water until neutral to obtain pre-activated sericite powder.
[0088] The preactivated sericite powder obtained above was placed in a high-speed mixer. Then, 2g of polydimethylsiloxane was evenly sprayed into the high-speed mixer and stirred thoroughly at a speed of 15000r / min for 30s. After stirring, the mixture was placed in an oven at 120℃ and heated and dried for 2h. After cooling, modified sericite powder was obtained.
[0089] Comparative Example 3
[0090] Comparative Example 3 was carried out in accordance with Example 1, except that: the pre-activated sericite powder was placed in a high-speed mixer, and then 5g of toluene with a surface tension of 28.6mN / m was evenly sprayed into the high-speed mixer and stirred thoroughly.
[0091] Comparative Example 4
[0092] Comparative Example 4 was carried out in accordance with Example 2, except that: the above sericite powder was mixed with water to obtain an aqueous solution of sericite powder, and then the pH of the aqueous solution of sericite powder was adjusted to 10 with sodium hydroxide. The mixture was stirred for 4 hours, filtered after stirring, the solid was collected and washed with water until neutral to obtain pre-activated sericite powder.
[0093] Comparative Example 5
[0094] Comparative Example 5 was carried out in accordance with Example 3, except that: the above sericite powder was mixed with water to obtain an aqueous solution of sericite powder, and then the pH of the aqueous solution of sericite powder was adjusted to 5 with hydrochloric acid. The mixture was stirred for 3 hours, filtered after stirring, the solid was collected and washed with water until neutral to obtain pre-activated sericite powder.
[0095] The contact angle, oil absorption value, and hydrophobicity of the modified sericite powders prepared in Examples 1-7 and Comparative Examples 1-5 were tested, and the results are shown in Table 1. The friction coefficient of the modified sericite powders prepared in Examples 1-3 and Comparative Example 3 was tested, and the results are shown in Table 2. The specific test methods are as follows:
[0096] Contact angle: Weigh 6-7g of the powder to be tested into a container, place it in a powder pressing mold, and press it into a smooth powder cake under a pressure of about 2MPa using a powder press. Water is selected as the test solvent, and the contact angle of the powder cake is tested using an optical contact angle meter.
[0097] Oil absorption value: Weigh 2g of the powder to be tested into a stainless steel mortar using an electronic balance. Add the oil to be tested using a dropper, adding small amounts several times until most of the powder can adhere to the mortar. From this point on, grind thoroughly with the mortar after each drop. The endpoint is reached when all the powder can adhere to the mortar. Calculate the oil absorption value of 100g of powder in the final calculation.
[0098] Friction coefficient: On the test plane of the friction coefficient meter, spread the powder to be tested into a test sample of 200mm*80mm; after setting the experimental parameters, clamp the slider with the test surface of the slider facing downwards, and carry out the test.
[0099] Table 1
[0100]
[0101]
[0102] Table 2
[0103] powder static friction coefficient coefficient of kinetic friction Sericite (Example 1, unmodified) 0.543 0.650 Example 1: Sericite 0.509 0.632 Sericite (Example 2, unmodified) 0.503 0.599 Example 2: Sericite 0.476 0.578 Sericite (Example 3, unmodified) 0.451 0.582 Example 3: Sericite 0.429 0.558 Sericite (unmodified, Comparative Example 3) 0.543 0.650 Comparative Example 3: Sericite 0.525 0.643
[0104] Figure 1 The contact angle test diagrams for the modified sericite powders obtained in Examples 1, 2, 3, and Comparative Example 3 are provided by [the relevant authority / organization]. Figure 1 As shown in Table 1, the modified sericite powder prepared by the method of the present invention exhibits excellent hydrophobicity and oil absorption value. Furthermore, the comparison between unmodified and modified sericite in the examples and comparative examples in Table 2 shows that the modified sericite powder has a lower coefficient of friction compared to the unmodified powder. The comparison between the modified sericite in Examples 1-3 and the modified sericite in Comparative Example 3 in Table 2 shows that the modified sericite pretreated with a solvent with a surface tension less than or equal to 25 mN / m has a lower coefficient of friction.
[0105] Application Example 1
[0106] The modified sericite powder obtained in Example 1 of this invention and the untreated sericite powder were used in powder cakes, and the powder cake formulations are shown in Table 3.
[0107] Table 3
[0108]
[0109] The preparation of the test powder includes the following steps:
[0110] (1) Add the A phase raw material into the mixer in sequence and mix at high speed until uniform.
[0111] (2) Weigh the B phase raw material into a container and mix it evenly.
[0112] (3) Add phase B to phase A, mix evenly in a mixer, and then discharge.
[0113] (4) Press the obtained formula powder into cakes.
[0114] Thirty volunteers aged 23-45 were selected as research subjects. After applying the powder obtained from modified sericite and untreated sericite in Application Example 1, the number of volunteers who felt good, medium, or poor for each of the four evaluation points (adhesion to the skin, fineness, makeup longevity, and smoothness) was collected and recorded. The statistical results are shown in Table 4.
[0115] Table 4
[0116]
[0117] The results of the makeup experience of the 30 volunteers recorded above show that the powder obtained by applying the modified sericite powder of Example 1 has good skin adhesion, good skin feel, and excellent makeup holding effect and smoothness.
[0118] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0119] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.
Claims
1. A method for preparing modified sericite powder, characterized in that, Includes the following steps: Provides sericite powder; The sericite powder is pre-activated to obtain pre-activated sericite powder, wherein the pre-activation method is selected from method (a) and / or method (b), method (a) calcining the sericite powder, and method (b) acidifying the sericite powder with a strong acid at pH ≤ 4 or alkalizing the sericite powder with a strong alkali at pH ≥ 11. The pre-activated sericite powder is mixed with a volatile solvent and then dried to obtain pretreated sericite powder. The surface tension of the volatile solvent is 15 mN / m-25 mN / m. The volatile solvent is selected from at least one of isododecane, n-hexane, ethanol, isopropanol, low-viscosity silicone oil, and cyclopentamethoxysiloxane. The mass ratio of the volatile solvent to the pre-activated sericite powder is 3:100-15:
100. The drying temperature is 80℃-150℃ and the drying time is 1h-4h. The pretreated sericite powder was mixed with a modifier and modified to obtain modified sericite powder.
2. The method for preparing modified sericite powder according to claim 1, characterized in that, In the step of calcining the sericite powder, the calcination temperature is 300℃-500℃ and the calcination time is 3h-6h.
3. The method for preparing modified sericite powder according to claim 1, characterized in that, In the step of acidifying the sericite powder with a strong acid at a pH ≤ 4, the acidification time is 0.5h-4h.
4. The method for preparing modified sericite powder according to claim 1, characterized in that, In the step of alkalizing the sericite powder with a strong alkali under conditions of pH ≥ 11, the alkalization time is 0.5h-4h.
5. The method for preparing modified sericite powder according to claim 1, characterized in that, The strong acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, perchloric acid, permanganic acid, hydrobromic acid, and hydroiodic acid; the strong base is selected from at least one of sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, calcium hydroxide, barium hydroxide, and strontium hydroxide.
6. The method for preparing modified sericite powder according to claim 1, characterized in that, The modifier is selected from at least one of hydrogenated polydimethylsiloxane, polydimethylsiloxane, triethoxyoctylsilane, and amino-modified silicone oil.
7. The method for preparing modified sericite powder according to claim 1, characterized in that, In the step of modifying the pretreated sericite powder by mixing it with a modifier, the mass ratio of the modifier to the pretreated sericite powder is 1:100-10:
100.
8. A method for preparing modified sericite powder according to any one of claims 1-7.
9. The application of the modified sericite powder as described in claim 8 in the preparation of cosmetics.