Natural composite microcapsule repairing lipstick and preparation method thereof

Abstract

The invention particularly relates to the technical field of cosmetics, in particular to a natural composite microcapsule repairing lipstick and a preparation method thereof. The invention discloses an anti-aging moisturizing cream which is prepared from the following components in percentage by mass: composite microcapsules, beewax, palm wax, candelilla wax, hydrogenated lecithin, olive oil, caprylic / capric triglyceride, meadowfoam seed oil, camellia oil, shea butter, vitamin E oil, a laurel extract, Nisin, epsilon polylysine, caprylyl glycol and the balance of deionized water. The natural composite microcapsule repair lipstick disclosed by the invention realizes long-acting slow release of pigments, natural and lasting color development, deep moisturizing, oxidation resistance, acceleration of lip barrier repair, improvement of skin elasticity and enhancement of a skin care effect.

Description

Technical Field

[0001] The technical field of cosmetics, specifically relates to a natural composite microcapsule repair lip balm and its preparation method. Background Art

[0002] As a transitional area between human skin and mucous membranes, the lip tissue structure presents unique vulnerability: the extremely thin cutin layer lacks the support of hair follicles and sebaceous glands, and the natural barrier function is weak, resulting in a significantly higher water evaporation rate than other skin areas, and is vulnerable to the influence of the external environment, causing problems such as dryness, chapping, and deepening of lip lines.

[0003] In the field of existing color-changing lip balms, traditional pigments are commonly used with poor stability and easy fading. Conventional colorants often cause rapid attenuation of color rendering due to light, temperature, and lip environment. Most products rely on synthetic anti-corrosion systems and chemically synthesized wax substrates, which may not only cause skin discomfort, but also difficult to meet consumers' demands for natural and mild formulations. Although existing microcapsule technologies can partially improve the stability of pigment active ingredients, there are still obvious defects in the co-encapsulation of complex pigments and the control of compatibility with lipid matrices, often resulting in obvious particle sense, uneven coloring, or premature release of active ingredients in products. In addition, the high-temperature processing link of traditional processes is easy to damage plant active ingredients, and it is difficult to balance the synergistic expression of product color rendering persistence and skin care effects, which has become a key technical barrier restricting the development of high-quality natural lip balms. Summary of the Invention

[0004] One object of the present invention is to provide a natural composite microcapsule repair lip balm with long-lasting slow release of pigments, natural and long-lasting color rendering, deep moisturizing, antioxidant, accelerating lip barrier repair, improving skin elasticity and enhancing skin care effects.

[0005] Another object of the present invention is to provide a preparation method of a natural composite microcapsule repair lip balm, which can be used to prepare the above lip balm.

[0006] The present invention provides a natural composite microcapsule repair lip balm, which is composed of the following components in mass percentage: composite microcapsules: 1% - 5%, beeswax: 15% - 25%, carnauba wax: 8% - 16%, candelilla wax: 1% - 6%, hydrogenated lecithin: 0.5% - 4%, olive oil: 15% - 30%, caprylic / capric triglyceride: 5% - 20%, Limnanthes alba seed oil: 1% - 8%, camellia oil: 3% - 8%, shea butter: 3% - 8%, vitamin E oil: 0.5% - 4%, Centaurea cyanus extract: 0.5% - 3%, Nisin: 0.05% - 0.3%, ε-polylysine: 0.02% - 0.15%, caprylyl glycol: 0.1% - 0.5%, and the balance is deionized water;

[0007] The composite microcapsule is composed of a natural pigment wrapped by a bilayer of silica and chitosan, where: the natural pigment is a compound of shikonin, bombax pigment and sweet potato red in a mass ratio of (2:1:1); the silica shell layer is formed by the sol-gel method, and the outer chitosan layer is coated by electrostatic adsorption; the particle size of the composite microcapsule is 200-300 nm;

[0008] The sum of the mass percentages of the above components is 100%.

[0009] Preferably, the molecular weight of the outer chitosan layer is 10-50 kDa, and the degree of deacetylation is ≥85%.

[0010] Preferably, the total flavonoid content in the extract of thousand-day chrysanthemum is ≥8%, and it is obtained by supercritical CO2 extraction (pressure 25 MPa, extraction temperature 45 °C).

[0011] The present invention also provides a preparation method of a natural composite microcapsule repair lip balm, comprising the following steps:

[0012] 1) Preparation of composite microcapsules:

[0013] Disperse shikonin, bombax pigment, and sweet potato red in ethanol in a mass ratio of (2:1:1), add tetraethyl orthosilicate and ammonia water, adjust the pH to 9-10, stir at 40 °C for 4 hours to form pigment nanoparticles encapsulated by silica (particle size 50-100 nm), then disperse the silica pigment particles in 1% acetic acid solution, add chitosan (mass ratio of chitosan to silica is 1:3), adjust the pH to 5.5, stir at 40 °C for 2 hours, centrifuge and then freeze-dry to obtain the silica-chitosan composite microcapsule;

[0014] 2) Low-temperature emulsification of the wax base:

[0015] Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 60-80 °C to form an oil phase, then disperse hydrogenated lecithin in deionized water at 40 °C (water:oil = 1:4), form an aqueous phase and mix it with the oil phase, and homogenize and emulsify at a rotation speed of 8000-10000 rpm for 10 minutes to obtain an O / W emulsion;

[0016] 3) Gradient temperature-controlled addition of active ingredients:

[0017] First, add shea butter and camellia oil to the emulsion at 50 °C, stir at 500-600 rpm for 5 minutes, then cool down to 40 °C and add Limnanthes alba seed oil and vitamin E oil, stir at 400-500 rpm for 3 minutes, and finally cool down to 35 °C and add the extract of thousand-day chrysanthemum, stir at 300-400 rpm for 2 minutes;

[0018] 4) Oriented dispersion of microcapsules and preservatives:

[0019] Add the composite microcapsules to the mixed substrate, and perform high-pressure homogenization treatment at 50-60 MPa for 3 times to make the particle size D90 of the microcapsules <10 μm. Then add Nisin, ε-polylysine, and octanediol, and stir at a low speed at 35 °C for 10 minutes;

[0020] 5) Vacuum degassing and condensation curing:

[0021] Perform vacuum degassing on the mixed material liquid at -0.05 to 0.1 MPa for 15 minutes, and then inject it into the mold and refrigerate and cure it at 4-6 °C for 2 hours.

[0022] Preferably, the cyclic pressure of the high-pressure homogenization treatment is 50-80 MPa, and the number of cycles is 1-5 times.

[0023] Preferably, the cooling rate is controlled at 1-5 °C per minute during the condensation curing stage.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are:

[0025] 1) The silica-chitosan bilayer structure realizes the long-term slow release of pigments, with natural and lasting color development. At the same time, it endows the microcapsules with antibacterial properties, avoiding the risk of pigment deterioration and lip infection.

[0026] 2) The compound of hydrogenated lecithin and natural wax balances the hardness and ductility of the paste. The low-temperature emulsification process retains the activity of the ingredients, and the touch is smooth and non-greasy.

[0027] 3) The synergy of Limnanthes alba seed oil and Centaurea cyanus extract provides deep moisturization, antioxidant effects, and accelerates the repair of the lip barrier, improving skin elasticity and enhancing the skin care effect.

[0028] 4) The combination of Nisin, ε-polylysine, and octanediol safely replaces synthetic preservatives, has high antibacterial efficiency and no irritation, and conforms to the development trend of green cosmetics. Specific embodiments

[0033] In order to more fully understand the technical content of the present invention, the present invention will be further introduced and described below in combination with specific embodiments; obviously, the following described embodiments are only a part of the embodiments of the present invention, rather than all embodiments; based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0034] The present invention provides a natural composite microcapsule repair lip balm, which is composed of the following components in mass percentages: composite microcapsules: 1% - 5%, beeswax: 15% - 25%, palm wax: 8% - 16%, candelilla wax: 1% - 6%, hydrogenated lecithin: 0.5% - 4%, olive oil: 15% - 30%, caprylic / capric triglyceride: 5% - 20%, Limnanthes alba seed oil: 1% - 8%, camellia oil: 3% - 8%, shea butter: 3% - 8%, vitamin E oil: 0.5% - 4%, Centaurea cyanus extract: 0.5% - 3%, Nisin: 0.05% - 0.3%, ε-polylysine: 0.02% - 0.15%, caprylyl glycol: 0.1% - 0.5%, and the balance is deionized water;

[0035] The composite microcapsules are composed of natural pigments wrapped by a double layer of silica and chitosan. Among them: the natural pigments are a compound of lithospermum erythrorhizon pigment, bombax malabaricum pigment and sweet potato red in a mass ratio of (2:1:1); the silica shell layer is formed by the sol-gel method, and the chitosan outer layer is coated by electrostatic adsorption; the particle size of the composite microcapsules is 200 - 300 nm;

[0036] The sum of the mass percentages of the above components is 100%.

[0037] In an embodiment of the present invention, the molecular weight of the chitosan outer layer is 10 - 50 kDa, and the deacetylation degree is ≥85%. Chitosan is a natural polysaccharide with broad-spectrum antibacterial properties and can hinder the growth of various bacteria. The antibacterial mechanism is as follows:

[0038] Electrostatic adsorption: The amino groups on chitosan are protonated under acidic conditions and bind to negatively charged bacteria through electrostatic force, causing the bacteria to flocculate and precipitate, thereby reducing the growth and reproduction rate of the bacteria.

[0039] Interference with the synthesis of cell walls and membranes: Chitosan can interfere with the synthesis of bacterial cell walls and affect the stability of cell membranes, resulting in cell lysis and rupture.

[0040] Inhibition of nucleic acid and protein synthesis: Low-molecular-weight chitosan can enter the interior of pathogen cells, may bind to the DNA inside the pathogen cells, hinder its transcription process, and thus affect the replication of DNA and the synthesis of proteins.

[0041] Chelation: The -OH and -NH2 groups in chitosan molecules have a chelating effect on metal ions under specific pH conditions, and can chelate with the metal ions in pathogen cells and trace elements in nutrients, thereby inhibiting the growth and reproduction of cells.

[0042] In an embodiment of the present invention, the total flavonoid content in the Centaurea cyanus extract is ≥8%, and it is obtained by supercritical CO2 extraction (pressure 25 MPa, extraction temperature 45°C).

[0043] The present invention also provides a method for preparing a natural composite microcapsule repair lip balm, comprising the following steps:

[0044] 1) Preparation of composite microcapsules:

[0045] Disperse shikonin, bombax pigment, and sweet potato red in ethanol according to the mass ratio (2:1:1), add tetraethyl orthosilicate and ammonia water, adjust the pH to 9-10, stir at 40 °C for 4 hours to form pigment nanoparticles encapsulated by silica (particle size 50-100 nm). Then disperse the silica pigment particles in a 1% acetic acid solution, add chitosan (mass ratio to silica 1:3), adjust the pH to 5.5, stir at 40 °C for 2 hours, centrifuge and then freeze-dry to obtain silica-chitosan composite microcapsules;

[0046] 2) Low-temperature emulsification of waxy base:

[0047] Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 60-80 °C to form an oil phase. Then disperse hydrogenated lecithin in deionized water at 40 °C (water:oil = 1:4) to form an aqueous phase, mix it with the oil phase, and homogenize and emulsify at a speed of 8000-10000 rpm for 10 minutes to obtain an O / W emulsion;

[0048] 3) Gradient temperature-controlled addition of active ingredients:

[0049] First, add shea butter and camellia oil to the emulsion at 50 °C, stir at 500-600 rpm for 5 minutes, then cool down to 40 °C and add Limnanthes alba seed oil and vitamin E oil, stir at 400-500 rpm for 3 minutes, and finally cool down to 35 °C and add Centaurea cyanus extract, stir at 300-400 rpm for 2 minutes;

[0050] 4) Oriented dispersion of microcapsules and preservatives:

[0051] Add the composite microcapsules to the mixed base, perform high-pressure homogenization treatment at 50-60 MPa for 3 times to make the particle size D90 of the microcapsules < 10 μm, add Nisin, ε-polylysine, and caprylyl glycol, and stir at low speed at 35 °C for 10 minutes;

[0052] 5) Vacuum degassing and condensation curing:

[0053] Perform vacuum degassing on the mixed material liquid at -0.05 to 0.1 MPa for 15 minutes, inject it into a mold, and refrigerate and cure at 4-6 °C for 2 hours.

[0054] In an embodiment of the present invention application, the cycle pressure of the high-pressure homogenization treatment is 50-80 MPa, and the cycle number is 1-5 times.

[0055] In an embodiment of the present invention application, the cooling rate in the condensation and solidification stage is controlled to be 1 - 5 °C per minute of temperature drop.

[0056] Example 1

[0057] A preparation method of a natural composite microcapsule repair lip balm, containing the following components (wt%):

[0058] Composite microcapsules: 3% (shikonin: kapok: sweet potato red = 2:1:1), beeswax 20%, carnauba wax 12%, candelilla wax 3%, hydrogenated lecithin 2%, olive oil 22%, caprylic / capric triglyceride 12%, limnanthes alba seed oil 4%, camellia oil 5%, shea butter 5%, vitamin E oil 2%, thousand - day chrysanthemum extract 1.5% (total flavonoids ≥ 8%), Nisin 0.1%, ε - polylysine 0.08%, caprylyl glycol 0.3%, and the balance is deionized water.

[0059] The steps of its preparation method include:

[0060] 1) Preparation of composite microcapsules:

[0061] Disperse shikonin, kapok pigment, and sweet potato red in ethanol according to the mass ratio (2:1:1), add tetraethyl orthosilicate and ammonia water, adjust the pH to 9.5, stir at 40 °C for 4 hours to form pigment nanoparticles encapsulated by silica (particle size 80 nm). Then disperse the silica pigment particles in 1% acetic acid solution, add chitosan (mass ratio to silica 1:3, molecular weight 30 kDa, deacetylation degree 90%), adjust the pH to 5.5, stir at 40 °C for 2 hours, and after centrifugation, freeze - dry to obtain silica - chitosan composite microcapsules with a particle size of 250 nm;

[0062] 2) Low - temperature emulsification of the wax base:

[0063] Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 75 °C to form an oil phase. Then disperse hydrogenated lecithin in deionized water at 40 °C (water:oil = 1:4) to form an aqueous phase, mix it with the oil phase, and homogenize and emulsify at 8000 rpm for 10 minutes to obtain an O / W emulsion;

[0064] 3) Gradient temperature - controlled addition of active ingredients:

[0065] First, add shea butter and camellia oil to the emulsion at 50 °C, stir at 500 rpm for 5 minutes, then cool down to 40 °C and add limnanthes alba seed oil and vitamin E oil, stir at 400 rpm for 3 minutes, and finally cool down to 35 °C and add thousand - day chrysanthemum extract, stir at 300 rpm for 2 minutes;

[0066] 4) Directional dispersion of microcapsules and preservatives:

[0067] Add the composite microcapsules to the mixed substrate and perform high-pressure homogenization treatment at 65 MPa three times to make the particle size of the microcapsules D90 = 8 μm. Then add Nisin, ε-polylysine, and octyldodecanol, and stir at a low speed at 35 °C for 10 minutes;

[0068] 5) Vacuum degassing and condensation curing:

[0069] Perform vacuum degassing on the mixed material liquid at -0.08 MPa for 15 minutes, and then inject it into a mold and refrigerate and cure at 5 °C for 2 hours.

[0070] Example 2

[0071] A preparation method of a natural composite microcapsule repair lip balm, containing the following components (wt%):

[0072] Composite microcapsules: 5% (shikonin: kapok flower: sweet potato red = 2:1:1), beeswax 25%, carnauba wax 16%, candelilla wax 6%, hydrogenated lecithin 4%, olive oil 15%, caprylic / capric triglyceride 5%, limnanthes alba seed oil 1%, camellia oil 3%, shea butter 3%, vitamin E oil 0.5%, thousand-day chrysanthemum extract 0.5%, Nisin 0.3%, ε-polylysine 0.15%, octyldodecanol 0.5%, and the balance is deionized water.

[0073] The steps of its preparation method include:

[0074] 1) Preparation of composite microcapsules:

[0075] Disperse shikonin pigment, kapok flower pigment, and sweet potato red in ethanol according to the mass ratio (2:1:1), add tetraethyl orthosilicate and ammonia water, adjust the pH to 9.5, and stir at 40 °C for 4 hours to form pigment nanoparticles (particle size 80 nm) wrapped with silica. Then disperse the silica pigment particles in a 1% acetic acid solution, add chitosan (mass ratio of chitosan to silica is 1:3, molecular weight 50 kDa, deacetylation degree 92%), adjust the pH to 5.5, stir at 40 °C for 2 hours, and after centrifugation, freeze-dry to obtain silica-chitosan composite microcapsules with a particle size of 250 nm;

[0076] 2) Low-temperature emulsification of waxy substrate:

[0077] Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 75 °C to form an oil phase. Then disperse hydrogenated lecithin in deionized water at 40 °C (water:oil = 1:4) to form an aqueous phase, and then mix it with the oil phase and homogenize and emulsify at 8000 rpm for 10 minutes to obtain an O / W emulsion;

[0078] 3) Gradient temperature control for adding active ingredients:

[0079] First, shea butter and camellia oil were added to the emulsion at 50 °C, and stirred at 500 rpm for 5 minutes. Then, the temperature was lowered to 40 °C, and limnanthes alba seed oil and vitamin E oil were added, and stirred at 400 rpm for 3 minutes. Finally, the temperature was lowered to 35 °C, and centaurea cyanus extract was added, and stirred at 300 rpm for 2 minutes;

[0080] 4) Oriented dispersion of microcapsules and preservatives:

[0081] The composite microcapsules were added to the mixed substrate, and subjected to high-pressure homogenization treatment at 50 MPa for 5 times to make the microcapsule particle size D90 = 6 μm. Nisin, ε-polylysine, and octyldodecanol were added, and stirred at low speed at 35 °C for 10 minutes;

[0082] 5) Vacuum degassing and condensation curing:

[0083] The mixed material liquid was degassed under vacuum at -0.05 MPa for 15 minutes, injected into a mold, and refrigerated and cured at 4 °C for 2 hours. The cooling rate was controlled at 3 °C per minute during the condensation curing stage.

[0084] Example 3

[0085] A preparation method of a natural composite microcapsule repair lip balm, containing the following components (wt%):

[0086] Composite microcapsules: 1% (shikonin: bombax ceiba flower: ipomoea batatas red = 2:1:1), beeswax 15%, carnauba wax 8%, candelilla wax 1%, hydrogenated lecithin 0.5%, olive oil 30%, caprylic / capric triglyceride 20%, limnanthes alba seed oil 8%, camellia oil 8%, shea butter 8%, vitamin E oil 4%, centaurea cyanus extract 3%, Nisin 0.05%, ε-polylysine 0.02%, octyldodecanol 0.1%, and the balance is deionized water.

[0087] The steps of its preparation method include:

[0088] 1) Preparation of composite microcapsules:

[0089] Shikonin pigment, bombax ceiba flower pigment, and ipomoea batatas red were dispersed in ethanol according to the mass ratio (2:1:1). Tetraethyl orthosilicate and ammonia water were added, and the pH was adjusted to 9.5. Stir at 40 °C for 4 hours to form pigment nanoparticles (particle size 80 nm) wrapped with silica. Then, the silica pigment particles were dispersed in 1% acetic acid solution, and chitosan (mass ratio to silica 1:3, molecular weight 10 kDa, deacetylation degree 85%) was added, and the pH was adjusted to 5.5. Stir at 40 °C for 2 hours, centrifuged and freeze-dried to obtain silica-chitosan composite microcapsules with a particle size of 250 nm;

[0090] 2) Low-temperature emulsification of waxy substrate:

[0091] Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 75 °C to form an oil phase. Then disperse hydrogenated lecithin in deionized water at 40 °C (water:oil = 1:4) to form an aqueous phase, which is then mixed with the oil phase and homogenized and emulsified at 8000 rpm for 10 minutes to obtain an O / W emulsion;

[0092] 3) Gradient temperature-controlled addition of active ingredients:

[0093] First, add shea butter and camellia oil to the emulsion at 50 °C and stir at 500 rpm for 5 minutes. Then cool down to 40 °C and add Limnanthes alba seed oil and vitamin E oil, and stir at 400 rpm for 3 minutes. Finally, cool down to 35 °C and add Centaurea cyanus extract, and stir at 300 rpm for 2 minutes;

[0094] 4) Directed dispersion of microcapsules and preservatives:

[0095] Add the composite microcapsules to the mixed substrate and perform high-pressure homogenization treatment at 80 MPa once to make the particle size of the microcapsules D90 = 9 μm. Add Nisin, ε-polylysine, and caprylyl glycol, and stir at low speed at 35 °C for 10 minutes;

[0096] 5) Vacuum degassing and condensation curing:

[0097] Perform vacuum degassing on the mixed material liquid at -0.1 MPa for 15 minutes, inject it into a mold, and refrigerate and cure at 6 °C for 2 hours. Control the cooling rate at 5 °C per minute during the condensation curing stage.

[0098] Comparative Example 1

[0099] Compared with Example 1, the only difference is that the composite microcapsules are replaced with two-color capsules (prepared according to Example 1 of CN107349112B).

[0100] Comparative Example 2

[0101] Compared with Example 1, the only difference is that candelilla wax is replaced with hydrogenated lecithin, and the mass content remains unchanged.

[0102] Comparative Example 3

[0103] Compared with Example 1, the only difference is that ozokerite is replaced with candelilla wax, and the mass content remains unchanged.

[0104] Comparative Example 4

[0105] Compared with Example 1, the only difference is that Paeonia suffruticosa Andr. seed oil is replaced with Centaurea cyanus extract, and the mass content remains unchanged.

[0106] Comparative Example 5

[0107] Compared with Example 1, the only difference is that camellia oil is replaced with Limnanthes alba seed oil, and the mass content remains unchanged.

[0108] Comparative Example 6

[0109] Compared with Example 1, the difference is only that 0.35% of benzoate is replaced by 0.1% of Nisin, 0.05% of ε-polylysine, and 0.2% of caprylyl glycol.

[0110] Comparative Example 7

[0111] Compared with Example 1, the difference is only that shikonin is replaced by kapok pigment, and the mass content remains unchanged.

[0112] Test 1: Detection Results and Analysis of Microbiological Indicators

[0113] The total number of colonies, the number of mold and yeast colonies, and the heavy metals such as lead, mercury, cadmium, and arsenic were detected for the natural composite microcapsule repair lip balms prepared in Examples 1-3 and Comparative Examples 1-6. The operation method was carried out in accordance with the "Technical Specifications for Cosmetics Safety" (2015 Edition) of the country.

[0114] The results showed that the natural composite microcapsule repair lip balms prepared in Examples 1-3 and Comparative Examples 1-6 did not grow bacteria at the dilution concentrations of 10 -1 、10 -2 、10 -3 The total number of colonies was counted as <10 CFU / g, and the number of mold and yeast colonies was also <10 CFU / g at the dilution concentrations of 110 -1 、10 -2 、10 -3 . It shows that the natural composite microcapsule repair lip balm is not contaminated, and the total number of colonies, mold and yeast indicators meet the "Technical Specifications for Cosmetics Safety" (2015 Edition) of the country.

[0115] The detection results of the lead, mercury, cadmium, and arsenic contents in the natural composite microcapsule repair lip balms prepared in Examples 1-3 and Comparative Examples 1-6 all meet the requirements for heavy metals in the "Technical Specifications for Cosmetics Safety" (2015 Edition) of the country. It can be seen that the lead, mercury, cadmium, and arsenic contents in the natural composite microcapsule repair lip balm of the present invention all meet the requirements.

[0116] Test 2: Comparison of Microcapsule Sustained Release Performance

[0117] Take 0.5 g of the lip balms in Experimental Example 1 and Comparative Example 1, dissolve them in 10 ml of phosphate buffer solution with pH 5.5, and shake well. Then transfer the dispersion to a 50 ml centrifuge tube, place it in a constant temperature shaker and continue to shake. Samples are taken at 0 h, 1 h, 3 h, 6 h, 12 h, and 24 h respectively. The samples are filtered and centrifuged. The absorbance value of the supernatant is measured with a UV spectrophotometer and the cumulative release rate is calculated. The cumulative release rate is the amount of free pigment at the current time point / the total amount of pigment in the microcapsules × 100%. Each group of experiments is repeated 3 times, and the results are averaged. The results are shown in Table 1.

[0118] Table 1

[0119]

[0120] The results show that the sustained-release effect in Example 1 is stronger than that in Comparative Example 1, indicating that the composite microcapsule structure of the present invention has a delayed release effect on the pigment and the color development is more lasting.

[0121] Test 3: Paste ductility and hardness test

[0122] Penetrometer and texture analyzer were used to test the hardness and ductility of the paste for Examples 1-3 and Comparative Examples 2-6. To test the hardness: first inject the lipstick into a standard mold, then place it on the test bench, start the penetrometer, test, repeat 5 times and take the average value. Calculation formula: Penetrometer = needle sinking depth / 0.1 (unit: mm). The smaller the penetration, the harder the paste. To test the ductility: first inject the lipstick into a standard mold, then place it on the test bench, start the texture analyzer, and move the probe at a uniform speed on the surface of the paste at a set speed. Record the resistance value (N) in real time, and take the stable resistance value (25-35mm) in the middle of the stroke to calculate the average value. The lower the resistance value, the better the ductility. The results are shown in Table 2.

[0123] Table 2

[0124]

[0125] The results show that the penetration and ductility values of Comparative Examples 2 and 3 are higher than the others, indicating that hydrogenated lecithin and candelilla wax are beneficial for optimizing the formula, improving the hardness and ductility of lipstick, and improving the smoothness of application.

[0126] Test 4: Active ingredient effect test

[0127] For Examples 1-3 and Comparative Examples 2-6, lip moisture content (%) and lip skin elasticity were measured using a skin moisture loss tester (iMate). The test results were expressed as the ratio of rebound value Ur to maximum skin stretch value Uf. The closer Ur / Uf is to 1, the better the skin elasticity. A spectrophotometer (3nhPS2080) was used to measure lip color change (ΔE, the difference in skin color before and after application of the natural composite microcapsule repair lipstick). A larger ΔE indicates more color remaining on the lips, a more saturated color, and better gloss. The test results are shown in Table 3.

[0128] Table 3

[0129]

[0130] The results showed that the moisturizing and skin elasticity effects after use of Examples 1-3 were better than those of the comparative examples, especially more significant compared with Comparative Examples 4-5, and the color development difference was more significant compared with Comparative Example 7. The results indicated that the combination of Limnanthes alba seed oil and Centaurea cyanus extract had synergistic effects, the compound pigment was reasonable, and the components of the lip balm formula were rationally formulated.

[0131] Experiment 5: Inhibition zone experiment

[0132] Take 100 μL of the cultured Staphylococcus aureus and spread it on the surface of the agar. Then gently press the Oxford cup on the surface of the agar. Add 200 μL of the sample (Example 1, Comparative Example 6, benzalkonium chloride, blank control, 0.1% concentration, dissolved in sterile PBS) into the Oxford cup, and place it in an incubator at 37 °C for incubation for 24 hours. Record the diameter of the inhibition zone, and repeat the test 3 times for each group of experiments. Result determination: diameter ≥ 15 mm: strong antibacterial;

[0133] 10 - 15 mm: moderate antibacterial; ≤ 10 mm: weak or no antibacterial. The results are shown in Table 4.

[0134] Table 4

[0135] Sample Example 1 Comparative Example 6 Benzalkonium chloride Blank control Inhibition zone diameter 15.52 15.50 20.20 0

[0136] The results showed that there was no significant difference in the diameter of the inhibition zone between Example 1 and Comparative Example 6, and the natural preservative could replace the synthetic preservative to achieve the same antibacterial effect.

[0137] The above are all the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle described in the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A natural composite microcapsule repair lip balm, characterized in that, Composed of the following components by mass percentage : Compound microcapsules: 1% - 5%, beeswax: 15% - 25%, carnauba wax: 8% - 16%, candelilla wax: 1% - 6%, hydrogenated lecithin: 0.5% - 4%, olive oil: 15% - 30%, caprylic / capric triglyceride: 5% - 20%, Limnanthes alba seed oil: 1% - 8%, camellia oil: 3% - 8%, shea butter: 3% - 8%, vitamin E oil: 0.5% - 4%, Centaurea cyanus extract: 0.5% - 3%, Nisin: 0.05% - 0.3%, ε - polylysine: 0.02% - 0.15%, caprylyl glycol: 0.1% - 0.5%, and the balance is deionized water; The compound microcapsules are composed of natural pigments wrapped by a silica - chitosan bilayer, where: the natural pigments are a compound of lithospermum erythrorhizon pigment, bombax malabaricum pigment, and sweet potato red in a mass ratio of 2:1:1; the silica shell layer is formed by the sol - gel method, and the chitosan outer layer is coated by electrostatic adsorption; the particle size of the compound microcapsules is 200 - 300nm; The sum of the mass percentages of the above - mentioned components is 100%.

2. The natural composite microcapsule repair lip balm according to claim 1, wherein: The molecular weight of the chitosan outer layer is 10 - 50 kDa, and the deacetylation degree is ≥85%.

3. The natural composite microcapsule repair lip balm according to claim 1, characterized in that: The total flavonoid content in the Centaurea cyanus extract is ≥8%, and it is obtained by supercritical CO2 extraction at a pressure of 25 MPa and an extraction temperature of 45°C.

4. A method for preparing the natural composite microcapsule repair lip balm according to any one of claims 1-3, characterized in that, Including the following steps: 1) Preparation of compound microcapsules: Disperse lithospermum erythrorhizon pigment, bombax malabaricum pigment, and sweet potato red in ethanol according to a mass ratio of 2:1:1, add tetraethyl orthosilicate and ammonia water, adjust the pH to 9 - 10, stir at 40°C for 4 hours to form pigment nanoparticles wrapped by silica with a particle size of 50 - 100nm. Then disperse the silica - pigment particles in a 1% acetic acid solution, add chitosan with a mass ratio of 1:3 to silica, adjust the pH to 5.5, stir at 40°C for 2 hours, and after centrifugation, freeze - dry to obtain silica - chitosan compound microcapsules; 2) Low - temperature emulsification of the waxy substrate: Melt beeswax, carnauba wax, candelilla wax, olive oil, and caprylic / capric triglyceride at 60 - 80°C to form an oil phase. Then disperse hydrogenated lecithin in deionized water at 40°C with a volume ratio of water to oil of 1:4 to form an aqueous phase, which is then mixed with the oil phase, and homogenize and emulsify at a speed of 8000 - 10000 rpm for 10 minutes to obtain an O / W emulsion; 3) Gradient temperature - controlled addition of active ingredients: First, add shea butter and camellia oil to the emulsion at 50°C, stir at 500 - 600 rpm for 5 minutes, then cool to 40°C and add Limnanthes alba seed oil and vitamin E oil, stir at 400 - 500 rpm for 3 minutes, and finally cool to 35°C and add Centaurea cyanus extract, stir at 300 - 400 rpm for 2 minutes; 4) Oriented dispersion of microcapsules and preservatives: Add the compound microcapsules to the mixed substrate, perform high - pressure homogenization treatment at 50 - 60 MPa for 3 times to make the particle size D90 of the microcapsules < 10μm, add Nisin, ε - polylysine, and caprylyl glycol, and stir at low speed at 35°C for 10 minutes; 5) Vacuum degassing and condensation curing: The mixed material liquid is subjected to vacuum degassing at -0.05 to 0.1 MPa for 15 minutes, and then injected into the mold and refrigerated and cured at 4 to 6 °C for 2 hours.

5. The preparation method according to claim 4, wherein: The circulating pressure of the high-pressure homogenization treatment is 50 to 80 MPa, and the number of circulation times is 1 to 5 times.

6. The preparation method according to claim 4, characterized in that: During the condensation and curing stage, the cooling rate is controlled at 1 to 5 °C per minute.

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