Composite sunscreen material as well as preparation method and application thereof

Abstract

The invention discloses a composite sunscreen material as well as a preparation method and application thereof. The preparation method comprises the following steps: adding a zinc nitrate solution into a mixed solution of 2-methylimidazole and a small molecule chemical sun-screening agent, stirring for reaction, washing, filtering and drying to obtain a sun-screening agent-embedded MOF material; and slowly adding a tetraethyl silicate solution into the MOF material ethanol solution embedded with the sun-screening agent, reacting, standing, washing, filtering, and drying to obtain the sun-screening material. According to the composite sun-screening material, a chemical sun-screening agent state is converted into a physical sun-screening agent state, the particle size is controlled to be 1-2 microns, a small-molecule chemical sun-screening agent can be effectively prevented from permeating into the skin, and the safety risk caused by the fact that the chemical sun-screening agent directly makes contact with the skin or even enters the skin is reduced. Meanwhile, the oleophylic sun-screening agent is modified into the hydrophilic sun-screening agent, so that the greasy feeling brought by the sun-screening agent is eliminated, the grease added for dissolving the sun-screening agent in the sun-screening formula is reduced, and a fresh and non-greasy skin feeling can be brought to the sun-screening product.

Description

Technical Field

[0001] The present invention relates to the technical field of personal care, and in particular to a composite sunscreen material and a preparation method and application thereof. Background Art

[0002] Ultraviolet rays are the main research focus of photoaging at this stage. Ultraviolet rays are divided into three bands: UVA, UVB, and UVC. Among them, UVC is almost completely absorbed by the ozone layer and cannot reach the earth's surface. UVB is an ultraviolet ray with a wavelength of 280-320nm. Most of UVB is absorbed by the skin epidermis and will not cause changes in keratinocyte DNA. However, due to its high energy, it will cause strong photodamage to the skin and even cause skin cancer. UVA is an ultraviolet ray with a wavelength of 320-400nm. It has strong penetrating power and can reach the dermis of the skin, destroying skin collagen and elastin, leading to the formation of wrinkles. Its damage is cumulative and is the main cause of photoaging. At the same time, it stimulates melanin production, resulting in uneven skin color. Therefore, in order to make the skin healthier and delay aging, sun protection has attracted more and more attention, and the frequency and amount of use are also increasing. However, the safety of sunscreen products has also caused concerns among scientific researchers and consumers.

[0003] The latest research published in the medical journal JAMA on May 6, 2019 found that several common chemical ingredients in sunscreen can enter the blood after only one day of use. The sunscreen avobenzone was detected in the blood at levels as high as 4.3ng / mL, the sunscreen oxybenzone was detected at levels as high as 209.6ng / mL, and the sunscreen octocrylene was detected at levels as high as 7.8ng / mL. The blood drug concentrations far exceeded the prescribed safety threshold of 0.5ng / mL. The high levels of these ingredients in the blood can lead to safety issues. Research results on common sunscreen ingredients confirmed that six sunscreens in sunscreen can penetrate into the blood. Among them, the sunscreen avobenzone was detected in the blood at levels as high as 7.1ng / mL, oxybenzone was as high as 258.1ng / mL, octocrylene was as high as 7.8ng / mL, homosalate was as high as 23.1ng / mL, octinoxate was as high as 5.8ng / mL, and octinoxate was as high as 7.9ng / mL, which far exceeded the safety threshold of 0.5ng / mL and may pose risks to human health and potential safety hazards.

[0004] In November 2021, "Daily Chemical Industry" reported the research results of the transdermal absorption and safety assessment of 6 commonly used sunscreens. The 6 chemical sunscreens, including isopentyl methoxycinnamate, butyl methoxydibenzoylmethane, 4-methylbenzylidene camphor, ethylhexyl triazone, benzophenone-3, and bis-ethylhexyloxyphenol methoxyphenyl triazine, will be absorbed through the skin, especially benzophenone-3, with a transdermal absorption rate of 36.66%, indicating that chemical sunscreens can easily pass through the skin barrier and be absorbed by the skin, and even enter the blood circulation system, causing potential health risks.

[0005] Metal organic framework (MOF) is a new type of porous material. It is a solid material with a periodic network structure constructed by coordination between metal ions or metal clusters and organic bridging ligands. MOF materials have important application prospects in gas adsorption, separation, sensing, catalysis and other fields due to their advantages such as large specific surface area, high porosity, regular pores, adjustable pore size, diversified topological structure and tailorability. Patent CN202110284143.X discloses a MOF block porous material and a preparation method thereof. The prepared MOF block porous material contains ZIF-8. Patent CN202310245206.X discloses a cyclodextrin bio-MOF sunscreen material preparation method and its cosmetic application. The preparation of cyclodextrin bio-MOF material loaded with sunscreen can effectively prevent sunscreen from penetrating into the skin, reduce the safety risks caused by direct contact of sunscreen with the skin or even entering the skin, and provide a good idea for the application of MOF materials in sunscreen cosmetics. Cyclodextrin can exist stably under alkaline and neutral conditions, but it will be partially hydrolyzed into glucose and non-cyclic maltose under acidic conditions. The prepared cyclodextrin bio-MOF material is stable in oil but not stable enough in water. The present invention innovatively uses ZIF-8 porous MOF material to load and adsorb lipophilic small molecule chemical sunscreen agents, and then coats a layer of hydrophilic silica (SiO 2 ) encapsulation prevents sunscreen from leaking out and contacting the skin, forming a more stable MOF-SiO 2 The composite sunscreen material converts the chemical sunscreen into a physical sunscreen and modifies the lipophilic sunscreen into a hydrophilic sunscreen, thereby improving the safety of the sunscreen while enhancing the refreshing skin feel and sun protection index of the sunscreen product. In addition, the toxicity problem of MOF is solved after silica encapsulation.

[0006] In view of this, the present invention is proposed. Summary of the invention

[0007] The object of the present invention is to provide a method for preparing a composite sunscreen material, the preparation process used is simple, low-carbon and environmentally friendly, the yield is high, and the prepared composite sunscreen material has good stability.

[0008] The object of the present invention is to provide a composite sunscreen material, which effectively adsorbs small molecule chemical sunscreens into porous MOF materials, and uses hydrophilic silica to encapsulate chemical sunscreens to prevent them from seeping out. The composite sunscreen material converts the chemical sunscreen state into a physical sunscreen state, and the particle size is controlled at 1-2 microns, which can effectively prevent small molecule chemical sunscreens from penetrating into the skin, and reduce the safety risks caused by chemical sunscreens directly contacting the skin or even entering the skin. At the same time, the lipophilic sunscreen is modified into a hydrophilic sunscreen, eliminating the greasy feeling brought by the sunscreen, and reducing the grease added in the sunscreen formula to dissolve the sunscreen, which can bring a refreshing and non-greasy skin feel to the sunscreen product. Moreover, the toxicity problem of MOF is solved after silica encapsulation.

[0009] The purpose of the present invention is to provide a MOF-SiO 2 Application of composite sunscreen materials in the preparation of sunscreen cosmetics.

[0010] The purpose of the present invention is achieved by at least one of the following technical solutions.

[0011] In a first aspect, the present invention provides a method for preparing a composite sunscreen material, wherein the composite sunscreen material is a MOF-SiO2 composite sunscreen material embedded with a chemical sunscreen agent. 2 Composite sunscreen materials;

[0012] The specific preparation method is as follows: first, zinc nitrate solution is added to a mixed solution of 2-methylimidazole and a chemical sunscreen, stirred for reaction, and then allowed to stand for 24 hours, washed, filtered, and then dried, to prepare a MOF material encapsulating the sunscreen in one step; then, tetraethyl silicate solution is slowly added to the MOF material solution encapsulating the sunscreen, stirred for reaction, and then allowed to stand for 48 hours, washed, filtered, and then dried, to prepare MOF-SiO 2 Composite sunscreen material.

[0013] The composite sunscreen material prepared in the present invention effectively adsorbs small molecule chemical sunscreens into porous MOF materials, encapsulates the chemical sunscreens with hydrophilic silica to prevent their leakage, and improves the stability of the sunscreens.

[0014] In the above method, the chemical sunscreen is an oil-soluble sunscreen with a molecular weight of less than 500, including 3-benzylidene camphor (molecular weight: 240.34), isopentyl p-methoxycinnamate (molecular weight: 248.32), ethylhexyl salicylate (molecular weight: 250.33), 4-methylbenzylidene camphor (molecular weight: 254.37), homosalate (molecular weight: 262.34), dibenzophenone-3 (molecular weight: 275.15), dimethyl PABA ethylhexyl ester (molecular weight: 277.4), methoxy One or more of ethylhexyl cinnamate (molecular weight: 290.4), benzophenone-4 (molecular weight: 308.31) and benzophenone-5 (molecular weight: 330.29), butyl methoxydibenzoylmethane (molecular weight: 310.39), polyacrylamidemethylbenzylidene camphor (molecular weight: 323.44), PEG-25 p-aminobenzoic acid (molecular weight: 357.4), octocrylene (molecular weight: 361.48), diethylaminohydroxybenzoyl hexyl benzoate (molecular weight: 397.51).

[0015] In the above method, the solvent for preparing the zinc nitrate solution, the mixed solution of 2-methylimidazole and chemical sunscreen agent, and the tetraethyl silicate solution is one or more of methanol, ethanol, cyclohexane, and ethyl acetate.

[0016] In the above method, the weight ratio of zinc nitrate to 2-methylimidazole is 1:1-1.5; the weight ratio of 2-methylimidazole to sunscreen is 1:1-5, and the weight ratio of MOF material encapsulating the sunscreen to tetraethyl silicate is 1:2-8.

[0017] In the above method, the particle size of the MOF material encapsulating the sunscreen is controlled to be 0.1-1 micron, and the MOF-SiO 2 The particle size of the composite sunscreen material is controlled at 1-2 microns.

[0018] In the above method, the specific surface area of ​​the MOF material encapsulating the sunscreen agent is greater than 1000 m2 / g and the pore size is less than 50 nanometers.

[0019] In a second aspect, the present invention provides a composite sunscreen material, which uses the aforementioned MOF-SiO 2 The composite sunscreen material is prepared by a preparation method.

[0020] Furthermore, the MOF-SiO 2 The composite sunscreen material is hydrophilic, which can improve the greasy feeling caused by the sunscreen and reduce the oil added to the sunscreen formula to dissolve the sunscreen, thus bringing a refreshing and non-greasy skin feel to the sunscreen product.

[0021] Furthermore, the MOF-SiO 2The composite sunscreen material uses MOF materials with silica encapsulated sunscreen agents to solve the toxicity problem of MOF and provide an effective solution for the safe application of MOF in cosmetics.

[0022] Furthermore, the MOF-SiO 2 Composite sunscreen materials will not be absorbed through the skin, and can effectively prevent small molecule chemical sunscreens from penetrating into the skin, reducing the safety risks posed by chemical sunscreens directly contacting the skin or even entering the skin.

[0023] In a third aspect, the present invention provides the use of the composite sunscreen material as described in the aforementioned embodiment in the preparation of sunscreen cosmetics, wherein the sunscreen cosmetics include sunscreen milk, sunscreen lotion, sunscreen cream, sunscreen liquid, sunscreen essence, sunscreen spray, sunscreen gel, isolation cream, isolation milk, isolation lotion, BB cream, bare face cream, liquid foundation, shampoo, conditioner or toner.

[0024] The present invention has the following beneficial effects:

[0025] The method for preparing the composite sunscreen material provided in this embodiment first embeds the lipophilic small molecule chemical sunscreen agent in the porous MOF, and then encapsulates the chemical sunscreen agent with hydrophilic silica to prevent its leakage. The process is simple, the reaction is fast, the yield is high, the stability is strong, the safety is good, and the economic benefits are significant.

[0026] At the same time, the present invention innovatively embeds small molecule chemical sunscreens in porous MOF materials, and uses silicon dioxide to encapsulate small molecule chemical sunscreens to prevent them from seeping out, which can effectively prevent small molecule chemical sunscreens from penetrating into human skin and causing potential irritation, allergic reactions, and even entering the blood. The prepared sunscreen products are safer and milder, and the MOF toxicity problem is effectively solved; at the same time, the oil-soluble sunscreen can be modified into a water-soluble sunscreen complex under the action of hydrophilic silicon dioxide, reducing the greasy feeling of the sunscreen products and making them more moist and refreshing. 2 Composite sunscreen materials can be used to develop high-tech sunscreen cosmetics that are gentler, safer, more moisturizing and skin-friendly. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0028] The present invention provides a method for preparing a composite sunscreen material, which comprises the following steps:

[0029] S1. Preparation of MOF materials for encapsulating sunscreen

[0030] First, 2-methylimidazole and a small molecule chemical sunscreen are mixed in an anhydrous ethanol solution at a weight ratio of 1:1-5, and dissolved evenly by ultrasonic treatment. Then, an anhydrous ethanol solution of zinc nitrate with a weight ratio of zinc nitrate to 2-methylimidazole of 1:1-1.5 is dissolved evenly by ultrasonic treatment. The anhydrous ethanol solution of zinc nitrate is slowly added to the mixed solution of 2-methylimidazole and the small molecule chemical sunscreen, stirred for 1 hour, left to stand for 24 hours, centrifuged at a centrifugal speed of 4000r / min for 5 minutes, the upper layer solution is poured off, washed with anhydrous ethanol 3 times, and dried in an oven at 50°C to prepare a MOF material encapsulating the sunscreen. The obtained material has a particle size of 0.1-1 microns, a pore size of less than 50 nanometers, a specific surface area of ​​more than 1000m2 / g, and a sunscreen encapsulation rate of up to 60%.

[0031] S2. Preparation of MOF-SiO 2 Composite sunscreen material

[0032] Add appropriate amount of water and anhydrous ethanol to the sunscreen MOF material prepared by S1, sonicate for half an hour, add 5 times the weight of the sunscreen MOF material, hexadecyl trimethyl ammonium bromide, stir for 3-5 minutes, then add 2-methyl imidazole equal to the weight of hexadecyl trimethyl ammonium bromide and stir for 10-20 minutes, then slowly drop 2-8 times the weight of the sunscreen MOF material in anhydrous ethanol mixture of tetraethyl silicate, add while stirring, and continue stirring for 1-2 hours after the addition is completed. Filter the above solution, wash it with anhydrous ethanol 3 times, soak it in anhydrous ethanol for 2 days, filter it, place the solid in an oven at 45-50°C for drying, and then place it in a vacuum drying oven at 80-85°C for 12 hours to prepare MOF-SiO 2 Composite sunscreen material. The particle size of the obtained material is 1-2 microns.

[0033] The embedded chemical sunscreen is an oil-soluble sunscreen with a molecular weight of less than 500, including one or more of 3-benzylidene camphor, isopentyl p-methoxycinnamate, ethylhexyl salicylate, 4-methylbenzylidene camphor, homosalate, benzophenone-3, benzophenone-4 and benzophenone-5, dimethyl PABA ethylhexyl ester, ethylhexyl methoxycinnamate, butyl methoxydibenzoylmethane, polyacrylamide methylbenzylidene camphor, PEG-25 p-aminobenzoic acid, octocrylene, and diethylaminohydroxybenzoyl hexyl benzoate.

[0034] In this embodiment, by embedding the above-mentioned small molecule chemical sunscreen in a porous MOF, and then encapsulating the small molecule chemical sunscreen with hydrophilic silica to prevent its leakage, the potential irritation, allergic reaction and even entering the blood caused by the small molecule chemical sunscreen infiltration into human skin is effectively prevented, and the MOF toxicity problem is solved. At the same time, the oil-soluble sunscreen can be modified into a water-soluble sunscreen complex under the action of hydrophilic silica, reducing the greasy feeling of the sunscreen product and making it more moist and refreshing. A more gentle, safe, moist and skin-friendly high-tech sunscreen cosmetic is developed.

[0035] Furthermore, the present invention also provides the use of the composite sunscreen material in the preparation of sunscreen cosmetics, and the sunscreen cosmetics include sunscreen milk, sunscreen lotion, sunscreen cream, sunscreen liquid, sunscreen essence, sunscreen spray, sunscreen gel, isolation cream, isolation milk, isolation lotion, BB cream, natural cream, foundation liquid, shampoo, conditioner or toner. MOF-SiO 2 The weight percentage of the composite sunscreen material in the formula of the sunscreen cosmetics is 5-30%.

[0036] The cosmetics used in the present invention are mainly sunscreen cosmetics obtained by mixing an oil phase and a water phase and adding other ingredients.

[0037] The oil phase is mainly composed of emulsifiers, co-emulsifiers, emollients, and sunscreens, but may also contain other ingredients as needed.

[0038] As the emulsifier, there is no particular limitation as long as it can form an oil-in-water (W / O) type or an oil-in-water (O / W) type emulsifier. For example, one or more of sucrose polystearate, sodium stearoyl glutamate, cetearyl glucoside, C12-20 alkyl glucoside, arachidyl glucoside, cetearyl olive oil ester, polysorbate-60, C20-22 alcohol phosphate, potassium cetyl phosphate, cetyl polyethylene glycol / polypropylene glycol-10 / 1 polydimethylsiloxane, lauryl polyethylene glycol / polypropylene glycol-18 / 18-dimethylsiloxane, polyethylene glycol-10 polydimethylsiloxane, sorbitan sesquiisostearate, polyglyceryl-3 diisostearate, polyglyceryl-3 methylglucose distearate, etc. can be used, and the amount added to the formula is 1-10%.

[0039] As auxiliary emulsifiers, for example, one or more of glyceryl stearate, PEG-60 hydrogenated castor oil, hydrogenated lecithin, etc. can be used, and the added amount in the formula is 0.2-5%.

[0040] As the emollient, the emollient commonly used in the cosmetics field can be used, without particular limitation. Specifically, one or more of cetyl alcohol, stearyl alcohol, cetearyl alcohol, behenyl alcohol, beeswax, C12-15 alcohol benzoate, caprylic / capric glyceride, butylene glycol dicaprylic / dicaprate, diisopropyl sebacate, dibutyl adipate, dioctyl carbonate, octyldodecanol, isopropyl palmitate, isododecane, isohexadecane, polydimethylsiloxane, octyl polymethylsiloxane, cyclopentasiloxane, phenyl trimethyl polysiloxane, squalane, squalene, vegetable oils and fats, etc. can be used. In addition to being an emollient, it can also be used as a solvent for a sunscreen, and the amount added in the formula is 5-30%.

[0041] The aqueous phase includes a humectant, a thickener, a pH adjuster, and may also contain other ingredients as required.

[0042] As the moisturizer, there is no particular limitation as long as it is a moisturizer commonly used in the cosmetics field. One or more of glycerin, propylene glycol, 1,3-propanediol, 1,3-butylene glycol, trehalose, seaweed extract, sodium hyaluronate, aloe extract, betaine, etc. can be used, and the amount added to the formula is 0.1-20%.

[0043] As a thickener, one or more of acrylic acid (ester) / C10-30 alkyl acrylate cross-linked polymer, carbomer, xanthan gum, etc. can be used, and the added amount in the formula is 0.1-10%.

[0044] As pH adjusters, one or more of arginine, sodium hydroxide, potassium hydroxide, triethanolamine, aminomethyl propanol, etc. can be used, and the added amount in the formula is 0-5%.

[0045] Other added ingredients include functional ingredients, flavors, pigments, preservatives, etc., and other ingredients may also be contained as needed.

[0046] As effective ingredients, it includes one or more of seaweed extract, scutellaria extract, Centella asiatica extract, licorice extract, moutan bark extract, mussel extract, ceramide, dextran, D-panthenol, etc. with skin soothing and repairing effects; one or more of niacinamide, vitamin C and its derivatives, arbutin, glutathione, tranexamic acid, phenethyl resorcinol, glycyrrhizin, potassium methoxysalicylate, bisabolol, etc. with whitening effects; one or more of seaweed extract, yeast extract, recombinant collagen, small molecule peptides, coenzyme Q10, astaxanthin, bosacein, ergothioneine, vitamin E, etc. with anti-aging effects, and the added amount in the formula is 0.1-20%.

[0047] As the flavor, it includes one or more of the essential oils with floral, fruity, grassy, ​​woody fragrances and compound daily flavors, and the addition amount in the formula is 0-2%.

[0048] As pigments, it includes one or more of chemical pigments, plant pigments, iron oxide, etc., and the added amount in the formula is 0-10%.

[0049] As preservatives, one or more of parabens, phenoxyethanol, benzyl alcohol, sodium benzoate, potassium sorbate, p-hydroxyacetophenone, etc. are included, and the amount added to the formula is 0-5%.

[0050] The formula of the sunscreen cosmetics in this embodiment may also contain an inorganic ultraviolet blocker, wherein the inorganic ultraviolet blocker includes one or both of zinc oxide and titanium dioxide, and the weight percentage in the formula is 0.05-20% zinc oxide and 0.05-20% titanium dioxide.

[0051] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0052] Example 1

[0053] This embodiment provides a MOF material for embedding a sunscreen agent, taking the small molecule chemical sunscreen agent diethylaminohydroxybenzoyl hexyl benzoate (DHHB) as an example, and the preparation method thereof includes:

[0054] First, 2-methylimidazole and sunscreen agent are mixed in an anhydrous ethanol solution at a weight ratio of 1:1-5 and dissolved evenly by ultrasonic treatment. Then, an anhydrous ethanol solution of zinc nitrate with a weight ratio of zinc nitrate to 2-methylimidazole of 1:1-1.5 is dissolved evenly by ultrasonic treatment. The anhydrous ethanol solution of zinc nitrate is slowly added to the mixed solution of 2-methylimidazole and sunscreen agent, stirred for 1 hour, allowed to stand for 24 hours, centrifuged at a centrifugal speed of 4000r / min for 5min, the upper solution is poured off, and the mixture is washed 3 times with anhydrous ethanol. The mixture is dried in an oven at 50°C to obtain the MOF material for encapsulating the sunscreen agent of Examples S1.1-S1.30, which has a particle size of 0.1-1 microns, a pore size of less than 50 nanometers, a specific surface area of ​​more than 1000m2 / g, and a sunscreen encapsulation rate of up to 60%.

[0055] The MOF material encapsulating the sunscreen was added with an appropriate amount of ethanol, hydrolyzed with concentrated hydrochloric acid, and then the concentration of the sunscreen was tested with an ultraviolet spectrophotometer. The weight of the encapsulated sunscreen and the encapsulation rate of the sunscreen were calculated according to the standard curve. The results are shown in Table 1.

[0056]

[0057] Where: m 1 is the weight of MOF material; m 2 is the weight of sunscreen embedded in MOF material.

[0058] The weight ratios of zinc nitrate to 2-methylimidazole and 2-methylimidazole to sunscreen were changed according to the parameters in Table 1 to obtain comparative examples D1.1-D1.4, and the results are shown in Table 1.

[0059] Table 1. Preparation of MOF materials for encapsulating sunscreen agents

[0060]

[0061]

[0062] Example 2

[0063] This embodiment provides a MOF-SiO 2 The composite sunscreen material comprises:

[0064] The MOF material for embedding the sunscreen agent prepared in the preferred embodiment S1.13 above is added with an appropriate amount of water and anhydrous ethanol, ultrasonicated for half an hour, 3-6 times the weight of the MOF material for embedding the sunscreen agent is added with hexadecyl trimethyl ammonium bromide and stirred for 3-5 minutes, and then 2-methylimidazole equal to the weight of the MOF material for embedding the sunscreen agent is added and stirred for 10-20 minutes, and then 2-8 times the weight of the MOF material for embedding the sunscreen agent is slowly added with anhydrous ethanol mixed solution of tetraethyl silicate, while stirring and dropping, and stirring is continued for 1-2 hours after the addition is completed. The above solution is filtered, washed with anhydrous ethanol 3 times, and soaked in anhydrous ethanol for 2 days, filtered, and the solid is placed in an oven at 45-50°C for drying, and then placed in a vacuum drying oven at 80-85°C for 12 hours to prepare MOF-SiO 2 Composite sunscreen material. The particle size of the material is tested by scanning electron microscopy, and the average particle size is preferably 1-2 microns, and the preferred particle size is 1.1-1.3 microns.

[0065] Table 2. MOF-SiO 2 Preparation of composite sunscreen materials

[0066]

[0067]

[0068]

[0069] Example 3

[0070] MOF-SiO prepared in preferred embodiment S2.17 2 Composite sunscreen materials, after the sunscreen agent content is converted, 50% of the maximum amount of sunscreen agents allowed by Chinese regulations is added together with other raw materials in the basic formula recorded in Table 3. 2The sunscreen effects of 12 oil-soluble small molecule chemical sunscreens encapsulated in the composite sunscreen material were compared with those of untreated pure sunscreens. The results are shown in Table 4.

[0071] Table 3. Basic formula of sunscreen lotion

[0072]

[0073]

[0074] Preparation process: Heat the oil phase and water phase to 70-90℃ respectively, add the oil phase to the water phase, homogenize and emulsify for 5-10 minutes at a homogenization speed of 1500-2500r / min, then cool to 40-50℃, add MOF-SiO 2 The composite sunscreen material and other ingredients are stirred homogenously for 3-5 minutes, then cooled to 30-35°C while stirring, and filled after passing the inspection.

[0075] Table 4. MOF-SiO 2 Sunscreen effect of composite sunscreen materials

[0076]

[0077]

[0078]

[0079] The results in Table 4 show that compared with the pure sunscreen without treatment, the sunscreen treated by embedding and encapsulation has no effect on the sun protection ability of the sunscreen, and some sun protection indexes will even increase. It is possible that encapsulation can reduce the degradation of the sunscreen and improve the stability of the sunscreen.

[0080] Example S4.1 MOF-SiO 2 Cosmetic applications of composite sunscreen materials

[0081] Table 5. SPF50+ sunscreen formula (W / W%)

[0082]

[0083]

[0084] Preparation process: Heat the oil phase and water phase to 70-90℃ respectively, add the oil phase into the water phase, homogenize and emulsify for 3-5 minutes at a homogenization speed of 1500-2500r / min, and add MOF-SiO 2For the composite sunscreen material, homogenize and emulsify for 3-5 minutes, then cool to 40-50℃ while stirring, add the remaining ingredients, continue to homogenize and stir for 3-5 minutes, cool to 30-35℃, and fill after passing the inspection.

[0085] Comparative Example D4.1:

[0086] Table 6. SPF50+ sunscreen formula (W / W%)

[0087]

[0088]

[0089]

[0090] Preparation process: Heat the oil phase and water phase to 70-90℃ respectively, add the oil phase to the water phase, homogenize and emulsify for 5-10 minutes at a homogenization speed of 1500-2500r / min, then cool to 40-50℃, add other ingredients, continue to homogenize and stir for 3-5 minutes, then cool to 30-35℃ while stirring, and fill after passing the inspection.

[0091] Test Case 1: Skin Penetration Evaluation

[0092] The MOF material of Example S1.13 encapsulating the sunscreen agent, and Example S2.17 MOF-SiO 2 The composite sunscreen material was applied to fresh pig skin of the same area and massaged for 5 minutes, then left to stand for 12 hours and taped 20 times to remove the stratum corneum as much as possible. The remaining pig skin was soaked in methanol and ultrasonically treated, and then the sunscreen content in the soaking liquid was detected by high performance liquid chromatography. The results showed that no sunscreen was found to penetrate into the skin in Example S2.17, but a small amount of diethylamino hydroxybenzoyl hexyl benzoate was detected to penetrate into the skin in Example S1.13, indicating that the MOF-SiO encapsulated with silica in the present invention 2 Composite sunscreen materials can effectively prevent small molecule sunscreens from contacting the skin and penetrating into the skin.

[0093] Table 7. Skin penetration of sunscreen agents

[0094]

[0095]

[0096] The formula pastes of Example S4.1 and Comparative Example D4.1 were applied to fresh pig skin of the same area and massaged for 5 minutes, then left to stand for 12 hours and taped 20 times to remove the stratum corneum as much as possible. The remaining pig skin was soaked in methanol and ultrasonically treated, and then the sunscreen content in the soaking liquid was detected by high performance liquid chromatography. The results showed that no sunscreen was found to penetrate into the skin in Example S4.1, but ethylhexyl methoxycinnamate, ethylhexyl salicylate, and diethylaminohydroxybenzoyl hexyl benzoate were detected in Comparative Example D4.1, indicating that the MOF-SiO 2 The composite sunscreen material effectively blocks the skin penetration of small molecule sunscreen agents.

[0097] Table 8. Skin penetration of sunscreen agents

[0098]

[0099] Test Example 2: Chicken Embryo Test Safety Assessment

[0100] The safety of the formula pastes of Example S4.1 and Comparative Example D4.1 was evaluated using a chicken embryo test (chicken embryo chorioallantoic membrane vascular test), and 10 chicken embryos were tested respectively.

[0101] The test method is the industry standard SN / T 2329-2009 "Chicken Embryo Chorioallantoic Test for Eye Irritation / Corrosion of Cosmetics". The results are shown in Table 9:

[0102] Table 9. Chicken embryo test safety assessment table

[0103]

[0104] (Grading criteria: 0 - normal; 1 - ghost blood vessels; 2 - capillary congestion; 3 - very slight bleeding; 4 - mild bleeding; 5 - moderate bleeding; 6 - severe bleeding. The lower the score, the safer it is, and the higher the score, the less safe it is.)

[0105] From the test results, the MOF-SiO 2 Sunscreen products made from composite sunscreen materials are safer and solve the MOF toxicity problem.

[0106] Test Example 3: Sunscreen Effect Evaluation

[0107] The formula materials of Example S4.1 and Comparative Example D4.1 were tested for sun protection effect using the "Method for Determining the Sun Protection Index (SPF) of Sunscreen Cosmetics" in the "Technical Specification for Safety of Cosmetics" (2015 edition) issued by the State Food and Drug Administration.

[0108] Example S4.1 Sun protection index test results: SPF = 61.1;

[0109] Comparative Example D4.1 Sun Protection Index Test Result: SPF = 51.2;

[0110] The sun protection effect of Example S4.1 is significantly enhanced compared with that of Comparative Example D4.1, indicating that the MOF-SiO 2 Composite sunscreen materials can reduce the degradation of sunscreen agents and have a synergistically enhanced sunscreen effect.

[0111] Test Example 4: User Experience Evaluation

[0112] The formula pastes of Example S4.1 and Comparative Example D4.1 were tested and evaluated by 10 female testers for their use experience effects (freshness and mildness). They were used twice a day for 4 consecutive weeks. The testers' self-assessment results are shown in Table 10:

[0113] Table 10. Evaluation table of sunscreen formula usage experience

[0114]

[0115]

[0116] (A 10-point scale is used. A score of 10 for freshness is considered good freshness, 9 for second best, and 1 for freshness is considered greasy (not fresh enough); a score of 10 for mildness is considered very mild, 9 for second best, and 1 for mildness is considered irritating.)

[0117] The purpose of the present invention is to provide a composite sunscreen material, which effectively adsorbs small molecule chemical sunscreens into porous MOF materials, encapsulates chemical sunscreens with hydrophilic silica to prevent them from seeping out, and converts the chemical sunscreen state into a physical sunscreen state, with a particle size controlled at 1-2 microns, which can effectively prevent small molecule chemical sunscreens from penetrating into the skin, and reduce the safety risks caused by chemical sunscreens directly contacting the skin or even entering the skin. At the same time, the lipophilic sunscreen is modified into a hydrophilic sunscreen, eliminating the greasy feeling brought by the sunscreen, and reducing the grease added in the sunscreen formula to dissolve the sunscreen, which can bring a refreshing and non-greasy skin feel to the sunscreen product.

[0118] The method for preparing the composite sunscreen material provided in this embodiment first embeds the lipophilic small molecule chemical sunscreen agent in the porous MOF, and then encapsulates the chemical sunscreen agent with hydrophilic silica to prevent its leakage. The process is simple, the reaction is fast, the yield is high, the stability is strong, the safety is good, and the economic benefits are significant.

[0119] At the same time, the present invention innovatively embeds small molecule chemical sunscreens in porous MOF materials, and uses silicon dioxide to encapsulate small molecule chemical sunscreens to prevent them from seeping out, which can effectively prevent small molecule chemical sunscreens from penetrating into human skin and causing potential irritation, allergic reactions, and even entering the blood. The prepared sunscreen products are safer and milder, and the MOF toxicity problem is effectively solved. At the same time, the oil-soluble sunscreen can be modified into a water-soluble sunscreen complex under the action of hydrophilic silicon dioxide, reducing the greasy feeling of the sunscreen product and making it more moist and refreshing. Using the MOF-SiO 2 Composite sunscreen materials can be used to develop high-tech sunscreen cosmetics that are gentler, safer, more effective, moisturizing and skin-friendly.

[0120] In summary, the MOF-SiO 2 The composite sunscreen material preparation method embeds small molecule chemical sunscreens in porous MOF materials and uses silica to encapsulate the small molecule chemical sunscreens to prevent their leakage. This can effectively prevent the small molecule chemical sunscreens from penetrating into human skin and causing potential irritation, allergic reactions, and even entering the blood, thereby making sunscreen products safer and gentler, and effectively solving the MOF toxicity problem. It can also reduce the degradation of sunscreens, thereby synergistically enhancing the sunscreen effect.

[0121] At the same time, the oil-soluble sunscreen agent can be modified into a water-soluble sunscreen compound under the action of hydrophilic silica, which reduces the greasy feeling of the sunscreen product and makes it more moist and refreshing. 2 Composite sunscreen materials can be used to develop high-tech sunscreen cosmetics that are gentler, safer, more effective, moisturizing and skin-friendly.

[0122] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a composite sunscreen material, characterized in that: The composite sunscreen material is a MOF-SiO2 composite sunscreen material that embeds a chemical sunscreen agent; The preparation method is as follows: first, zinc nitrate solution is added to a mixed solution of 2-methylimidazole and a chemical sunscreen, the mixture is stirred for reaction, allowed to stand, washed, filtered, and then dried, thereby preparing a MOF material encapsulating a sunscreen agent in one step; then, tetraethyl silicate solution is added to the MOF material solution encapsulating a sunscreen agent, the mixture is stirred for reaction, allowed to stand, washed, filtered, and then dried, thereby preparing a MOF-SiO2 composite sunscreen material.

2. The method for preparing a composite sunscreen material according to claim 1, characterized in that: The chemical sunscreen is an oil-soluble sunscreen with a molecular weight of less than 500, including one or more of 3-benzylidene camphor, isopentyl p-methoxycinnamate, ethylhexyl salicylate, 4-methylbenzylidene camphor, homosalate, benzophenone-3, dimethyl PABA ethylhexyl ester, ethylhexyl methoxycinnamate, benzophenone-4, benzophenone-5, butyl methoxydibenzoylmethane, polyacrylamide methylbenzylidene camphor, PEG-25 p-aminobenzoic acid, octocrylene, and diethylaminohydroxybenzoyl hexyl benzoate.

3. The method for preparing a composite sunscreen material according to claim 1, characterized in that: The solvents of the zinc nitrate solution, the mixed solution of 2-methylimidazole and chemical sunscreen, and the tetraethyl silicate solution are one or more of methanol, ethanol, cyclohexane, and ethyl acetate.

4. The method for preparing a composite sunscreen material according to claim 1, characterized in that: The weight ratio of zinc nitrate to 2-methylimidazole is 1:1-1.5; the weight ratio of 2-methylimidazole to sunscreen is 1:1-5; the weight ratio of MOF material encapsulating the sunscreen to tetraethyl silicate is 1:2-8.

5. The method for preparing a composite sunscreen material according to claim 1, characterized in that: The particle size of the MOF material encapsulating the sunscreen agent is controlled at 0.1-1 micron, and the particle size of the MOF-SiO2 composite sunscreen material is controlled at 1-2 microns; The specific surface area of ​​the MOF material for embedding the sunscreen agent is greater than 1000 m2 / g, and the pore size is less than 50 nanometers.

6. The method for preparing a composite sunscreen material according to claim 1, characterized in that: The specific steps are: S1. Preparation of MOF materials for embedding sunscreen agents: First, 2-methylimidazole and a small molecule chemical sunscreen are mixed in an anhydrous ethanol solution at a weight ratio of 1:1-5, and dissolved uniformly by ultrasonic treatment. Then, an anhydrous ethanol solution of zinc nitrate with a weight ratio of zinc nitrate to 2-methylimidazole of 1:1-1.5 is dissolved uniformly by ultrasonic treatment. The anhydrous ethanol solution of zinc nitrate is added to the mixed solution of 2-methylimidazole and the small molecule chemical sunscreen, stirred for reaction, allowed to stand, centrifuged, the upper solution is poured off, washed with anhydrous ethanol, and dried to prepare a MOF material encapsulating the sunscreen. S2. Preparation of MOF-SiO2 composite sunscreen material Add water and anhydrous ethanol to the sunscreen MOF material prepared by S1, and perform ultrasonic treatment for half an hour. Add hexadecyltrimethylammonium bromide and stir. Then add 2-methylimidazole and stir. Then, add a mixture of tetraethyl silicate and anhydrous ethanol dropwise while stirring. Continue stirring after the addition is completed. Filter the solution, wash with anhydrous ethanol, soak it in anhydrous ethanol, filter it, dry the solid, and then dry it in a vacuum drying oven at 80-85°C to prepare a MOF-SiO2 composite sunscreen material.

7. A composite sunscreen material MOF-SiO2 composite sunscreen material prepared by the preparation method according to any one of claims 1 to 6.

8. The composite sunscreen material according to claim 7, characterized in that: The MOF-SiO2 composite sunscreen material is hydrophilic, can improve the greasy feeling caused by the sunscreen, and reduce the oil added in the sunscreen formula to dissolve the sunscreen, which can bring a refreshing and non-greasy skin feel to the sunscreen product; the MOF-SiO2 composite sunscreen material will not be absorbed through the skin.

9. The MOF-SiO2 composite sunscreen material according to claim 7 is used in the preparation of sunscreen cosmetics.

10. The use according to claim 9, characterized in that: The sunscreen cosmetics include sunscreen milk, sunscreen lotion, sunscreen cream, sunscreen liquid, sunscreen essence, sunscreen spray, sunscreen gel, isolation cream, isolation milk, isolation lotion, BB cream, bare face cream, liquid foundation, shampoo, conditioner or toner.

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