A composition, method and application for reducing surface free radicals of titanium dioxide powder

Abstract

The present invention relates to the technical field of cosmetics, and particularly to a composition, a method and an application for reducing free radicals on the surface of titanium dioxide powder. The composition comprises polymethylsilsesquioxane and triethoxyoctylsilane; the mass ratio of polymethylsilsesquioxane to triethoxyoctylsilane is 1-4:1-3. On the surface of the titanium dioxide powder, the hydroxy free radicals on the powder surface are condensed by triethoxyoctylsilyl groups and the blocking effect of polymethylsilsesquioxane, thereby reducing the release of free radicals on the powder surface. The reduction of free radicals can improve the stability of active substances in the formula, be friendly to the skin, delay aging caused by free radicals in powders, increase the expiration date of active ingredients, and prevent free radicals from inducing skin aging.

Description

Technical Field

[0001] The present invention relates to the technical field of cosmetics, and in particular to a composition, method and application for reducing free radicals on the surface of titanium dioxide powder. Background Art

[0002] Free radicals, also known as "free radicals" in chemistry, refer to atoms or groups with unpaired electrons formed by homolytic cleavage of covalent bonds in the molecules of a compound under external conditions such as light and heat. Free radicals are very active because they contain unpaired electrons, so they are extremely unstable (especially hydroxyl radicals), so they will steal electrons from neighboring molecules (including fats, proteins, and DNA) to keep themselves in a stable state. In this way, the neighboring molecule becomes a new free radical, which then steals electricity. As a result of such a chain reaction, the structure of the cell is damaged, causing loss of cell function, gene mutation, and even death.

[0003] Therefore, many cosmetics on the market add antioxidant ingredients to maintain the stability of active ingredients. They can also reduce free radicals on the skin and reduce the aging and damage caused by free radicals to the skin.

[0004] However, in recent years, the demand for skin care foundation products has been increasing. Active ingredients are added to foundations, and there are more and more functional products. However, the titanium dioxide content of foundation products is very high. If the titanium dioxide packaging in the foundation powder is not properly handled and free radicals are generated, some functional ingredients in the product will be inactivated faster and fail to achieve the desired effect. Due to the high activity and strong oxidation reaction ability of free radicals, they can attack any molecules they encounter through oxidation. Free radicals can directly destroy collagen, make cell membranes lose elasticity and flexibility, reduce the immunity of skin cells, make the skin lose elasticity and luster, and the skin color will become dull, gray and yellow, and wrinkles will appear, which will promote skin aging.

[0005] In order to solve the problem of free radicals in the above-mentioned makeup products causing skin aging, minimizing the free radicals produced by titanium dioxide is an urgent issue that needs to be addressed. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a composition, method and application for reducing free radicals on the surface of titanium dioxide powder. The composition and method provided by the present invention can reduce free radicals on the surface of titanium dioxide powder.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a composition for reducing free radicals on the surface of titanium dioxide powder, comprising polymethylsilsesquioxane and triethoxyoctylsilane;

[0009] The mass ratio of the polymethylsilsesquioxane to the triethoxyoctylsilane is 1 to 4:1 to 3;

[0010] The molecular formula of the polymethylsilsesquioxane is (CH 3 -SiO 3 / 2 )x, where x is 315.78.

[0011] The present invention also provides a method for reducing surface free radicals of titanium dioxide powder using the composition described in the above technical solution, including the following steps:

[0012] 1) Mix the triethoxyoctylsilane with a dispersant to obtain a triethoxyoctylsilane solution;

[0013] 2) Spray the triethoxyoctylsilane solution obtained in step 1) onto the surface of the titanium dioxide powder, and dry it to obtain a silane-treated powder;

[0014] The mass ratio of the titanium dioxide powder to the triethoxyoctylsilane is 97 to 99:1 to 3;

[0015] 3) Mix the polymethylsilsesquioxane with a dispersion liquid to obtain a polymethylsilsesquioxane solution;

[0016] The mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 96 to 99:1 to 4;

[0017] 4) Mix the silane-treated powder obtained in step 2) with the polymethylsilsesquioxane solution obtained in step 3), and let it stand to obtain a standing product;

[0018] 5) Separate the solid and liquid of the standing product obtained in step 4), and dry the obtained solid to obtain a treated titanium dioxide powder.

[0019] Preferably, in step 1), the mass ratio of the triethoxyoctylsiloxane to the dispersant is 1:1;

[0020] The dispersant includes one or more of acetone, isododecane, cyclopentadimethylsiloxane, and ethanol;

[0021] The conditions for the mixing include: mixing at a rotation speed of 200 rpm for 30 min.

[0022] Preferably, in step 2), the triethoxyoctylsilane solution is sprayed onto the surface of the titanium dioxide powder in 3 to 4 times, and after each spraying, it is mixed at a rotation speed of 2000 rpm for 5 to 10 min;

[0023] The conditions for the drying include: temperature of 80 °C and time of 3 h.

[0024] Preferably, the mass ratio of polymethylsilsesquioxane to the dispersion liquid in step 3) is 1:1;

[0025] The dispersion liquid includes one or more of acetone, isododecane, cyclopentasiloxane, and ethanol;

[0026] The conditions for mixing include: mixing at a rotation speed of 200 rpm for 30 minutes.

[0027] Preferably, the mass ratio of the silane-treated powder solution to the polymethylsilsesquioxane solution in step 4) is 1:1 - 2;

[0028] The standing time is 12 hours.

[0029] Preferably, the conditions for drying in step 5) include: a temperature of 100 °C and a time of 5 hours.

[0030] The present invention also provides the application of the treated titanium dioxide powder obtained by the above technical solution in reducing free radicals in base makeup products.

[0031] The present invention also provides the application of the composition according to the above technical solution in reducing free radicals on the surface of titanium dioxide powder.

[0032] In the present invention, on the surface of titanium dioxide powder, the hydroxyl free radicals on the powder surface are condensed by triethoxyoctylsilyl groups and the blocking effect of polymethylsilsesquioxane, reducing the release of free radicals on the powder surface. The reduction of free radicals can improve the stability of active substances in the formula, be friendly to the skin, delay aging caused by powder free radicals, increase the effective period of active ingredients, and prevent free radicals from inducing skin aging.

[0033] Advantages of the present invention:

[0034] The total free radical release content of titanium dioxide treated with triethoxyoctylsiloxane + polymethylsilsesquioxane is less than that of untreated titanium dioxide and titanium dioxide treated with triethoxyoctylsiloxane, and there are also significant differences in the total free radical release content with the dosages of triethoxyoctylsiloxane and polymethylsilsesquioxane. Description of the Drawings

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments.

[0036] Figure 1 For the laboratory test results of titanium dioxide powder, from left to right are untreated titanium dioxide powder, titanium dioxide powder treated with triethoxyoctylsiloxane (Example 1), and titanium dioxide powder treated with triethoxyoctylsiloxane + polymethylsilsesquioxane (Example 2);

[0037] Figure 2 It is a parameter for the total free radical content of titanium dioxide powder during on-machine testing. Specific Embodiments

[0038] The present invention provides a composition for reducing free radicals on the surface of titanium dioxide powder, comprising polymethylsilsesquioxane and triethoxysilane octyl; the mass ratio of polymethylsilsesquioxane to triethoxysilane octyl is 1-4:1-3; the molecular formula of polymethylsilsesquioxane is (CH 3 -SiO 3 / 2 )x, where x is 315.78. Manufacturer: In the present invention, the polymethylsilsesquioxane is sourced from Momentive (Shanghai) Trading Co., Ltd., origin: Japan, product model: SilFormFlexible™ fluid. In the present invention, the polymethylsilsesquioxane and triethoxysilane octyl in the composition are preferably packaged separately.

[0039] The present invention provides a method for reducing free radicals on the surface of titanium dioxide powder using the composition described in the above technical solution, comprising the following steps:

[0040] 1) Mix the triethoxysilane octyl with a dispersant to obtain a triethoxysilane octyl solution;

[0041] 2) Spray the triethoxysilane octyl solution obtained in step 1) onto the surface of titanium dioxide powder, and dry it to obtain silane-treated powder;

[0042] The mass ratio of the titanium dioxide powder to triethoxysilane octyl is 97-99:1-3;

[0043] 3) Mix the polymethylsilsesquioxane with a dispersion liquid to obtain a polymethylsilsesquioxane solution;

[0044] The mass ratio of the titanium dioxide powder to polymethylsilsesquioxane is 96-99:1-4;

[0045] 4) Mix the silane-treated powder obtained in step 2) with the polymethylsilsesquioxane solution obtained in step 3), and let it stand to obtain a standing product;

[0046] 5) Separate the solid and liquid of the standing product obtained in step 4), and dry the obtained solid to obtain treated titanium dioxide powder.

[0047] The present invention mixes the triethoxyoctylsilane with a dispersant to obtain a triethoxyoctylsilane solution. In the present invention, the mass ratio of the triethoxyoctylsiloxane to the dispersant is preferably 1:1. In the present invention, the dispersant preferably includes one or several of acetone, isododecane, cyclopentadimethylsiloxane, and ethanol. In the present invention, the conditions for the mixing preferably include: mixing at a rotation speed of 200 rpm for 30 min.

[0048] The present invention sprays the obtained triethoxyoctylsilane solution onto the surface of titanium dioxide powder, and after drying, a silane-treated powder is obtained. The present invention has no special limitation on the titanium dioxide powder, and the titanium dioxide powder conventionally used in base makeup products can be adopted. In the present invention, the triethoxyoctylsilane solution is preferably sprayed onto the surface of the titanium dioxide powder in 3 to 4 times, and after each spraying, it is mixed at a rotation speed of 2000 rpm for 5 to 10 min to make the triethoxyoctylsilane solution uniformly adhere to the surface of the powder. In the present invention, the conditions for the drying preferably include: the temperature is 80 °C and the time is 3 h.

[0049] The present invention mixes the polymethylsilsesquioxane with a dispersion liquid to obtain a polymethylsilsesquioxane solution. In the present invention, the mass ratio of the polymethylsilsesquioxane to the dispersion liquid is preferably 1:1. In the present invention, the dispersion liquid preferably includes one or several of acetone, isododecane, cyclopentadimethylsiloxane, and ethanol. In the present invention, the conditions for the mixing preferably include: mixing at a rotation speed of 200 rpm for 30 min.

[0050] In the present invention, the mass ratio of the silane-treated powder solution to the polymethylsilsesquioxane solution is preferably 1:1 to 2. In the present invention, the standing time is preferably 12 h.

[0051] The present invention separates the solid and liquid of the obtained standing substance, and dries the obtained solid to obtain a treated titanium dioxide powder. In the present invention, the conditions for the drying preferably include: the temperature is 100 °C and the time is 5 h.

[0052] The present invention also provides the application of the treated titanium dioxide powder obtained by the method according to the above technical solution in reducing free radicals in base makeup products. The present invention has no special limitation on the base makeup products, and the base makeup products conventional in the art can be adopted.

[0053] The present invention also provides the application of the composition according to the above technical solution in reducing free radicals on the surface of titanium dioxide powder.

[0054] In order to further illustrate the present invention, the present invention will be described in detail below with reference to examples, but they should not be construed as limiting the protection scope of the present invention.

[0055] Example 1

[0056] A method for reducing surface free radicals of titanium dioxide powder, the steps are as follows:

[0057] (1) Mix triethoxy octyl silane and ethanol in a mass ratio of 1:1, and stir at 200 rpm for 30 min to obtain a transparent and uniform mixed solution;

[0058] (2) Spray the transparent and uniform mixed solution obtained in step (1) evenly on the surface of titanium dioxide powder in 3 times with a sprayer. After each spraying, mix at 2000 rpm for 10 min until the surface of the titanium dioxide powder is evenly attached with the transparent and uniform mixed solution; the mass ratio of the titanium dioxide powder to triethoxy octyl silane is 98:2;

[0059] (3) Dry the treated powder in an oven at 80 °C for 3 hours to obtain the powder treated with silane.

[0060] Example 2

[0061] The difference from Example 1 is that the mass ratio of titanium dioxide powder to triethoxy octyl silane is 99:1, and the rest is the same as Example 1, to obtain the powder treated with silane.

[0062] Example 3

[0063] The difference from Example 1 is that the mass ratio of titanium dioxide powder to triethoxy octyl silane is 97:3, and the rest is the same as Example 1, to obtain the powder treated with silane.

[0064] Comparative Example 1

[0065] The difference from Example 1 is that the mass ratio of titanium dioxide powder to triethoxy octyl silane is 99.5:0.5, and the rest is the same as Example 1, to obtain the powder treated with silane.

[0066] Comparative Example 2

[0067] The difference from Example 1 is that the mass ratio of titanium dioxide powder to triethoxy octyl silane is 96:4, and the rest is the same as Example 1, to obtain the powder treated with silane.

[0068] Example 4

[0069] (1) Mix triethoxy octyl silane and acetone in a mass ratio of 1:1, and stir at 200 rpm for 30 min to obtain a transparent and uniform mixed solution;

[0070] (2) The transparent and homogeneous mixed solution obtained in step (1) is evenly sprayed on the surface of titanium dioxide powder in three times using a sprayer. After each spraying, it is mixed at 2000 rpm for 10 minutes until the transparent and homogeneous mixed solution is evenly attached to the surface of the titanium dioxide powder; the mass ratio of the titanium dioxide powder to triethoxyoctylsilane is 98:2;

[0071] (3) The treated powder is dried in an oven at 80 °C for 3 hours to obtain the powder treated with silane;

[0072] (4) Polymethylsilsesquioxane (with the molecular formula (CH 3 -SiO 3 / 2 )x, where x is 315.78) is mixed with cyclopentadimethylsiloxane in a mass ratio of 1:1 and stirred at 200 rpm for 30 minutes to obtain a transparent and homogeneous mixed solution 1;

[0073] (2) The powder treated with silane obtained in step (3) is added to the mixed solution 1 obtained in step (4) and stirred thoroughly at 1500 rpm for 4 hours to make the polymethylsilsesquioxane fully adhere to the surface of the powder, and then left to stand for 12 hours; the mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 98:2;

[0074] (4) The cyclopentadimethylsiloxane in the supernatant of the material after the standing reaction is completely recovered. The remaining material is separated from the solvent and the powder by a suction filter. The powder after suction filtration is dried in an oven at 100 °C for 5 hours to obtain the powder with multiple surface treatments.

[0075] Example 5

[0076] The difference from Example 4 is that the mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 97:3, and the rest is the same as in Example 2, obtaining the powder with multiple surface treatments.

[0077] Example 6

[0078] The difference from Example 4 is that the mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 99:1, and the rest is the same as in Example 2, obtaining the powder with multiple surface treatments.

[0079] Example 7

[0080] The difference from Example 4 is that the mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 96:4, and the rest is the same as in Example 2, obtaining the powder with multiple surface treatments.

[0081] Comparative Example 3

[0082] The difference from Example 4 is that the mass ratio of titanium dioxide powder to polymethylsilsesquioxane is 99.5:0.5, and the rest is the same as in Example 2, obtaining a multi-surface-treated powder.

[0083] Comparative Example 4

[0084] The difference from Example 4 is that the mass ratio of titanium dioxide powder to polymethylsilsesquioxane is 95:5, and the rest is the same as in Example 2, obtaining a multi-surface-treated powder.

[0085] Laboratory test:

[0086] Experimental method: Prepare untreated titanium dioxide powder, titanium dioxide powder treated with triethoxyoctylsilane (Example 1), titanium dioxide powder treated with triethoxyoctylsilane + polymethylsilsesquioxane (Example 4), mix them evenly with pure alcohol, pour the mixture into a transparent container after mixing evenly, then continue to add an aqueous potassium iodide solution with a mass percentage of 10%, stir quickly and evenly, where the mass ratio of titanium dioxide powder: pure alcohol: 10% aqueous potassium iodide solution is 9:3:1. Try to avoid air residue in the container, cover the lid to seal it, and then carry out natural light irradiation for one week to promote the chemical reaction.

[0087] Experimental principle: Hydroxyl radicals will oxidize iodide ions to form elemental I 2 , making the solution turn yellow. The more free radicals released by titanium dioxide, the more elemental I 2 is formed, and the deeper the color.

[0088] Experimental results:

[0089] The results are shown in Figure 1 , and it can be seen from Figure 1 that the titanium dioxide powder treated with triethoxyoctylsilane + polymethylsilsesquioxane shows the lightest color, indicating that the content of free radicals released is less than that of untreated titanium dioxide and titanium dioxide treated with triethoxyoctylsilane.

[0090] Testing by a third-party testing agency:

[0091] Testing method: Weigh 20 mg of titanium dioxide powder and test the total free radical content on the machine. The instrument is an electron paramagnetic resonance spectrometer, and the instrument model is Bruker A300. The parameters are shown in Figure 2 .

[0092] Testing agency: Fuda Testing Technology Group Co., Ltd.

[0093] Test samples:

[0094] 1. Untreated titanium dioxide;

[0095] 2. Titanium dioxide treated with triethoxyoctylsilane (Example 1);

[0096] 3. Triethoxyoctylsiloxane-treated titanium dioxide (Example 2);

[0097] 4. Triethoxyoctylsiloxane-treated titanium dioxide (Example 3);

[0098] 5. Triethoxyoctylsiloxane-treated titanium dioxide (Comparative Example 1);

[0099] 6. Triethoxyoctylsiloxane-treated titanium dioxide (Comparative Example 2);

[0100] 7. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Example 4);

[0101] 8. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Example 5);

[0102] 9. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Example 6);

[0103] 10. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Example 7);

[0104] 11. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Comparative Example 3);

[0105] 12. Triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide (Comparative Example 4);

[0106] The test results are shown in Table 1.

[0107] Table 1 Titanium Dioxide Free Radical Test Results

[0108]

[0109] It can be concluded from Table 1 that the total free radical release content of triethoxyoctylsiloxane + polymethylsilsesquioxane-treated titanium dioxide is less than that of untreated titanium dioxide and triethoxyoctylsiloxane-treated titanium dioxide, and the dosages of triethoxyoctylsiloxane and polymethylsilsesquioxane also have significant differences in the total free radical release content.

[0110] Although the above embodiments have described the present invention in detail, they are only a part of the embodiments of the present invention, rather than all embodiments. People can also obtain other embodiments according to these embodiments without creative efforts, and these embodiments all fall within the protection scope of the present invention.

Claims

1. Application of the composition in reducing free radicals on the surface of titanium dioxide powder; The composition is polymethylsilsesquioxane and triethoxyoctylsilane; The mass ratio of the polymethylsilsesquioxane to triethoxyoctylsilane is 1-4:1-3; The molecular formula of the polymethylsilsesquioxane is (CH3 -SiO 3 / 2 )x, x is 315.78; The method for reducing free radicals on the surface of titanium dioxide powder by the composition comprises the following steps: 1) mixing the triethoxyoctylsilane with a dispersant to obtain a triethoxyoctylsilane solution; 2) spraying the triethoxyoctylsilane solution obtained in step 1) on the surface of titanium dioxide powder, and drying to obtain silane-treated powder; The mass ratio of the titanium dioxide powder to triethoxyoctylsilane is 97-99:1-3; 3) mixing the polymethylsilsesquioxane with a dispersion to obtain a polymethylsilsesquioxane solution; The mass ratio of the titanium dioxide powder to the polymethylsilsesquioxane is 96-99:1-4; 4) mixing the silane-treated powder obtained in step 2) and the polymethylsilsesquioxane solution obtained in step 3), and allowing the mixture to stand to obtain a standing product; 5) The solid-liquid separation of the static product obtained in step 4) is carried out, and the obtained solid is dried to obtain treated titanium dioxide powder.

2. The use according to claim 1, characterized in that: In the step 1), the mass ratio of triethoxycaprylylsiloxane to the dispersant is 1:1; The dispersant includes one or more of acetone, isododecane, cyclopentasiloxane and ethanol; The mixing conditions include: mixing at a rotation speed of 200 rpm for 30 minutes.

3. The use according to claim 1, characterized in that: In the step 2), the triethoxyoctylsilane solution is sprayed on the surface of the titanium dioxide powder 3 to 4 times, and after each spraying, the mixture is mixed at a speed of 2000 rpm for 5 to 10 minutes; The drying conditions include: temperature of 80° C. and time of 3 hours.

4. The use according to claim 1, characterized in that: In step 3), the mass ratio of polymethylsilsesquioxane to the dispersion is 1:1; The dispersion includes one or more of acetone, isododecane, cyclopentasiloxane and ethanol; the mixing conditions include: mixing for 30 minutes at a rotation speed of 200 rpm.

5. The use according to claim 1, characterized in that: In the step 4), the mass ratio of the silane-treated powder solution to the polymethylsilsesquioxane solution is 1:1 to 2; The standing time is 12 hours.

6. The use according to claim 1, characterized in that: The drying conditions in step 5) include: a temperature of 100° C. and a drying time of 5 hours.

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