A post-sun repair composition suitable for dry sensitive skin and its use

Abstract

The application discloses a post-sun repair composition suitable for dry and sensitive skin and application thereof, and belongs to the technical field of skin care products. The core active ingredients of the composition include fucus extract, matricaria extract, opuntia stricta stem extract and echinacea purpurea extract. The application aims at the pain points of dry and sensitive skin, such as weak skin barrier, poor water retention capacity, weak anti-inflammatory repair capacity, easy redness and sensitivity after sun exposure, and easy aging and dullness. Through accurate compounding and synergistic effect of the four active ingredients, a three-stage post-sun repair system is constructed: the first stage is rapid anti-inflammatory soothing, which immediately relieves the redness, burning, stinging and discomfort of dry and sensitive skin after sun exposure; the second stage is deep moisturizing and long-term water retention, which improves the dryness and tightness and peeling of the skin after sun exposure; the third stage is to repair the damaged skin barrier, inhibit abnormal deposition of melanin and resist ultraviolet-induced photoaging damage; and the post-sun damage can be comprehensively responded in multiple dimensions.

Description

Technical Field

[0001] This invention relates to the field of skincare technology, specifically to an after-sun repair composition suitable for dry and sensitive skin and its application. Background Technology

[0002] With increased ultraviolet radiation and outdoor activities, sunburn is becoming a more prominent issue. UVA and UVB rays in sunlight can penetrate the epidermis and superficial dermis, causing acute sunburn reactions such as erythema, edema, peeling, burning, and stinging. They also induce the production of large amounts of reactive oxygen species (ROS), accelerating skin aging and damaging the skin barrier function. For people with dry, sensitive skin, whose stratum corneum is thin, sebum secretion is low, and natural moisturizing factors are lacking, they are more prone to severe discomfort after sun exposure, such as dryness, peeling, tightness, stinging, redness, and itching. Furthermore, their skin barrier repair speed is much slower than that of normal skin.

[0003] Currently, most after-sun repair products on the market are based on single or simple compound ingredients such as aloe vera gel, panthenol, and centella asiatica extract, which have the following shortcomings: (1) There are few products specifically for dry and sensitive skin. Most products can only temporarily cool and soothe the skin, and cannot provide multiple effects such as deep moisturizing, barrier repair, and anti-inflammatory and redness reduction at the same time; (2) Some products add irritating ingredients such as alcohol, fragrance, and traditional preservatives, which aggravate the stinging and peeling of dry and sensitive skin; (3) There is a lack of multi-pathway synergistic repair design, which fails to comprehensively solve the after-sun problems from four dimensions: hydration and moisturizing, anti-inflammatory and soothing, anti-oxidative damage, and promoting barrier regeneration.

[0004] Therefore, developing a natural plant-derived repair composition specifically for dry, sensitive skin, which also provides immediate cooling and soothing after sun exposure, long-lasting hydration, barrier repair, and anti-oxidation and anti-inflammatory effects, has significant clinical and market value. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a post-sun repair composition and its application suitable for dry and sensitive skin. It solves the problems of existing post-sun products being poorly adapted to dry and sensitive skin, having limited functions, incomplete repair, and being unable to prevent photoaging. Through the scientific compounding of four natural plant extracts, it achieves staged, multi-level, and comprehensive repair of dry and sensitive skin after sun exposure, taking into account both immediate soothing and long-lasting repair, anti-aging and melanin-inhibiting effects, and the ingredients are gentle and highly tolerable.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a post-sun repair composition suitable for dry and sensitive skin, wherein, by weight, the main active ingredients include: 5-15 parts of Fucus vesiculosus extract, 3-10 parts of chamomile extract, 4-12 parts of Prickly pear stem extract, and 2-8 parts of Echinacea purpurea extract.

[0007] Furthermore, to optimize the synergistic effect, the preferred ratio of the main active ingredients is: 8-12 parts of Fucus vesiculosus extract, 5-8 parts of chamomile extract, 6-10 parts of Prickly pear cactus stem extract, and 4-6 parts of Echinacea purpurea extract.

[0008] Secondly, the present invention provides a method for preparing the post-sun repair composition for dry and sensitive skin as described in the first aspect, comprising the following steps: mixing the extracts of Fucus vesiculosus, chamomile, Opuntia ficus-indica stem extract, and Echinacea purpurea extract in proportion to weight to obtain the final product.

[0009] Thirdly, the present invention provides a cosmetic containing the after-sun repair composition for dry and sensitive skin described in the first aspect. The composition is added to the cosmetic in an amount of 0.5-10 wt%, preferably 1-8 wt%.

[0010] The cosmetics also include cosmetic excipients, including but not limited to moisturizers, thickeners, emulsifiers, skin moisturizers, antioxidants, pH adjusters, and fragrances.

[0011] Fourthly, the present invention provides the use of the composition described in the first aspect or the composition prepared by the method described in the second aspect in the preparation of cosmetics. The cosmetics are preferably after-sun repair sprays, repair gels, repair creams, repair masks, or repair serums.

[0012] The efficacy descriptions of each active ingredient are as follows: Fucus vesiculosus extract: Rich in fucoidan, fucoidan, mannitol, iodine, and various minerals. Its core function is powerful hydration and moisturizing, forming a breathable hydrating film on the skin surface to reduce transepidermal water loss (TEWL). It also possesses excellent antioxidant and anti-inflammatory activity, effectively eliminating excess free radicals generated after sun exposure, inhibiting metalloproteinase (MMP) activity, preventing collagen degradation, and promoting skin barrier repair. It is especially suitable for post-sun exposure repair of dry and sensitive skin.

[0013] Chamomile extract: Rich in bisabolol, chamomile azulene, and flavonoids. It is a classic soothing and anti-allergic ingredient that can quickly inhibit the release of inflammatory mediators such as histamine and leukotrienes from sun-exposed skin, relieving redness, burning, and stinging. Simultaneously, it promotes keratinocyte proliferation, accelerates the healing of damaged skin barriers, and has synergistic antioxidant properties, reducing UV-induced pigmentation.

[0014] Prickly pear cactus stem extract: Rich in cactus polysaccharides, flavonoids, vitamin E, and superoxide dismutase (SOD). It has extremely strong moisturizing and water-locking capabilities, forming a protective film on the skin surface to provide long-lasting hydration; it also has good anti-inflammatory, anti-swelling, and antioxidant effects, which can reduce post-sun edema and erythema, and protect cell membranes from lipid peroxidation damage, making it especially suitable for dry and dehydrated post-sun skin.

[0015] Purple Echinacea Extract: Rich in chicoric acid, echinacoside, and alkanamide compounds. It is a natural immunomodulator and anti-inflammatory component, effectively inhibiting UV-induced NF-κB pathway activation and reducing levels of inflammatory factors such as IL-6 and TNF-α; simultaneously promoting fibroblast proliferation and collagen synthesis, accelerating post-sun exposure dermal repair; and possessing mild antibacterial activity, preventing secondary infections of sun-exposed skin.

[0016] Beneficial effects Compared with the prior art, the present invention has the following beneficial effects: This invention combines extracts of Fucus vesiculosus, chamomile, Opuntia ficus-indica stem, and Echinacea purpurea. The ingredients work synergistically to overcome the shortcomings of traditional products that only provide single-function repair. It constructs a three-tiered repair system that provides immediate soothing, hydration and moisture retention, and deep anti-aging and melanin inhibition. It comprehensively addresses the acute and long-term photodamage problems of dry and sensitive skin after sun exposure from four dimensions: anti-inflammatory, moisturizing, repairing, and anti-photoaging. The repair is more thorough and the effect is more lasting. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. The described embodiments are only some preferred embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Unless otherwise specified, the experimental methods used in the embodiments are conventional or common methods in the art, and the materials and reagents used are commercially available unless otherwise specified.

[0019] The raw materials used in the examples and comparative examples are described below: Fucus vesiculosus extract: purchased from Guangzhou Baiyu Biotechnology Co., Ltd.; Matricaria extract: purchased from Xi'an Hengji Chemical Co., Ltd.; Prickly pear cactus stem extract: purchased from Xi'an Qiancao Biotechnology Co., Ltd.; Purple coneflower extract: purchased from SymFinity, a company specializing in purple coneflower extract. Calendula extract: purchased from Zhenghe (Guangzhou) Biotechnology Co., Ltd.

[0020] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0021] Example 1 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 10 parts of *Fucus vesiculosus* extract, 6 parts of *Chaenomeles speciosa* extract, 8 parts of *Opuntia ficus-indica* stem extract, and 5 parts of *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0022] Example 2 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 8 parts of *Fucus vesiculosus* extract, 5 parts of *Chaenomeles speciosa* extract, 6 parts of *Opuntia ficus-indica* stem extract, and 6 parts of *Echinacea purpurea* extract. The mixture is passed through a 100-mesh sieve.

[0023] Example 3 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 12 parts of *Fucus vesiculosus* extract, 5 parts of *Chaenomeles speciosa* extract, 10 parts of *Opuntia ficus-indica* stem extract, and 4 parts of *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0024] Example 4 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 5 parts of *Fucus vesiculosus* extract, 5 parts of *Chaenomeles speciosa* extract, 6 parts of *Opuntia ficus-indica* stem extract, and 2 parts of *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0025] Example 5 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 15 parts of *Fucus vesiculosus* extract, 4 parts of *Chaenomeles speciosa* extract, 3 parts of *Opuntia ficus-indica* stem extract, and 6 parts of *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0026] Example 6 A post-sun repair composition suitable for dry and sensitive skin, comprising, by weight: 10 parts of *Fucus vesiculosus* extract, 10 parts of *Chaenomeles speciosa* extract, 4 parts of *Opuntia ficus-indica* stem extract, and 8 parts of *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0027] Comparative Example 1 A suitable post-sun repair composition, by weight, comprises: 6 parts of chamomile extract, 8 parts of prickly pear stem extract, and 5 parts of echinacea extract. The above components are mixed evenly to obtain the final product.

[0028] Comparative Example 2 A suitable post-sun repair composition, by weight, comprises: 10 parts of *Fucus vesiculosus* extract, 8 parts of *Opuntia ficus-indica* stem extract, and 5 parts of *Echinacea purpurea* extract. The above components are mixed evenly to obtain the final product.

[0029] Comparative Example 3 A suitable post-sun repair composition, by weight, comprises: 10 parts of *Fucus vesiculosus* extract, 6 parts of *Chaenomeles speciosa* extract, and 5 parts of *Echinacea purpurea* extract. The above components are mixed evenly to obtain the final product.

[0030] Comparative Example 4 A suitable post-sun repair composition, by weight, comprises: 10 parts of *Fucus vesiculosus* extract, 6 parts of *Chaenomeles speciosa* extract, and 8 parts of *Opuntia ficus-indica* stem extract. The above components are mixed evenly to obtain the final product.

[0031] Comparative Example 5 A suitable post-sun repair composition, by weight, comprises: 1 part of *Fucus vesiculosus* extract, 15 parts of *Chaenomeles speciosa* extract, 5 parts of *Opuntia ficus-indica* stem extract, and 5 parts of *Echinacea purpurea* extract.

[0032] Mix the above components thoroughly to obtain the final product.

[0033] Comparative Example 6 A suitable post-sun repair composition, by weight, comprises: 10 parts of *Fucus vesiculosus* extract, 4 parts of *Chaenomeles speciosa* extract, 2 parts of *Opuntia ficus-indica* stem extract, and 15 parts of *Echinacea purpurea* extract. The above components are mixed evenly to obtain the final product.

[0034] Comparative Example 7 A suitable composition for post-sun repair, comprising, by weight: 10 parts trehalose, 6 parts matricaria flower extract, 8 parts *Opuntia ficus-indica* stem extract, and 5 parts *Echinacea purpurea* extract. The above components are mixed thoroughly to obtain the final product.

[0035] Comparative Example 8 A suitable post-sun repair composition, by weight, comprises: 10 parts of *Fucus vesiculosus* extract, 6 parts of *Calendula officinalis* extract, 8 parts of *Opuntia ficus-indica* stem extract, and 5 parts of *Echinacea purpurea* extract. The above components are mixed evenly to obtain the final product.

[0036] Table 1. Raw material composition (parts by weight) for Examples 1-6 and Comparative Examples 1-8 Example 1 10 6 8 5 / / Example 2 8 5 6 6 / / Example 3 12 5 10 4 / / Example 4 5 5 6 2 / / Example 5 15 3 4 6 / / Example 6 10 10 4 8 / / Comparative Example 1 / 6 8 5 / / Comparative Example 2 10 / 8 5 / / Comparative Example 3 10 6 / 5 / / Comparative Example 4 10 6 8 / / / Comparative Example 5 1 15 5 5 / / Comparative Example 6 10 4 2 15 / / Comparative Example 7 / 6 8 5 10 Comparative Example 8 10 / 8 5 6 Note: " / " indicates that this component is not present.

[0037] Efficacy verification test 1. Anti-inflammatory performance test Experimental materials: The cell line used was logarithmically growing RAW264.7 cells (Wuhan Saisios Biotechnology Co., Ltd.), and the TNF-α and IL-6 inflammatory factor detection kit (abcam).

[0038] The specific testing method is as follows: (1) Cell culture: Seed cells into culture flasks and 24-well culture plates at a density of 5 × 10⁶ cells / well. 5 The cells / mL were incubated in DMEM medium (Gibco) containing 10% fetal bovine serum at 37°C for 24 h in a 5% CO2 incubator. (2) Model making: Control group: Remove the supernatant from the 24-well plate, repeat in parallel with 5 wells, add 500 μL of DMEM culture medium and 100 μL of PBS solution to each well; Model group: Remove the supernatant from the 24-well plate, add 500 μL of DMEM culture medium and 100 μL of LPS solution to each of the 5 parallel wells.

[0039] Experimental group: Remove the supernatant from the 24-well plate, add 500 μL of DMEM culture medium, 100 μL of LPS and sample (example and comparative sample, concentration of 10 mg / mL) to each well in parallel 5 wells.

[0040] (3) Detection of inflammatory factor concentration: After incubation at 37℃ in a 5% CO2 incubator for 24 hours, the supernatant was collected. The sample was centrifuged in a centrifuge tube, and the supernatant was used for the detection of inflammatory factor concentration. Calculation: Inflammatory factor inhibition rate (%) = [(Average content of inflammatory factors in the model group - Average content of inflammatory factors in the experimental group) / (Average content of inflammatory factors in the model group - Average content of inflammatory factors in the control group)] × 100%.

[0041] Table 2. Inhibition rate of inflammatory factors (%) Example 1 85.7% 87.4% Example 2 83.1% 85.2% Example 3 84.3% 86.1% Example 4 78.0% 81.0% Example 5 75.4% 79.3% Example 6 80.2% 83.0% Comparative Example 1 52.9% 50.6% Comparative Example 2 47.1% 43.8% Comparative Example 3 49.6% 46.2% Comparative Example 4 50.4% 47.5% Comparative Example 5 55.4% 52.8% Comparative Example 6 60.0% 56.7% Comparative Example 7 57.7% 54.8% Comparative Example 8 62.5% 59.0% As shown in Table 2: 1) Examples 1-6 of the present invention all exhibited excellent anti-inflammatory activity. Among them, the TNF-α inhibition rate of Example 1 reached 85.7% and the IL-6 inhibition rate reached 87.4%. The TNF-α inhibition rate of Examples 2-6 was between 75.4% and 84.3%, and the IL-6 inhibition rate was between 79.3% and 86.1%, which were significantly higher than all comparative examples (the TNF-α inhibition rate of Comparative Examples 1-8 was only 47.1%-62.5%, and the IL-6 inhibition rate was only 43.8%-59.0%). 2) Among them, Comparative Examples 1-4 lacked the components Fucus vesiculosus extract, Matricaria champaca extract, Prickly pear cactus stem extract, and Echinacea purpurea extract, respectively, which led to a significant decrease in the inhibition rate of inflammatory factors. In particular, the inhibition rates of TNF-α and IL-6 in Comparative Example 2 decreased to 47.1% and 43.8%, respectively. This indicates that Matricaria champaca extract is the main anti-inflammatory component in the present invention. 3) However, after adjusting the dosage ratios of *Fucus vesiculosus* extract, *Chamaecyparis pilosa* extract, *Opuntia ficus-indica* stem extract, and *Echinacea purpurea* extract in Comparative Examples 5 and 6, the inhibition rates of inflammatory factors also showed a significant decrease. Similarly, after replacing *Fucus vesiculosus* extract with trehalose in Comparative Example 7 and replacing *Chamaecyparis pilosa* extract with calendula extract in Comparative Example 8, the inhibition rates of inflammatory factors also showed a significant decrease. This indicates that the dosage ratio of the four effective components in the embodiments of the invention is a key influencing factor in the inhibition of inflammatory factors. Replacing the components with components of similar efficacy cannot achieve a similar anti-inflammatory effect. Therefore, the four effective components in the embodiments of the invention can achieve a synergistic anti-inflammatory effect.

[0042] Application examples Application Examples 1-6 and Comparative Application Examples 1-8 of the present invention provide a repair essence, the components (mass percentage) of which are shown in Table 3; wherein, Application Examples 1-6 and Comparative Application Examples 1-8 respectively use the compositions described in Examples 1-6 and Comparative Examples 1-8.

[0043] Table 3. Ingredients of the Repair Essence (percentage by weight)

[0044] Preparation process: S1. Mix the components of phase B and heat to 55°C until completely dissolved to obtain the pre-prepared phase B; S2. Mix each component of phase A with water and stir. Heat to 75°C and homogenize at 6000 r / min for 5 min until completely dissolved. Then cool to 50°C and add the pre-prepared phase B at 300 r / min and stir. Then cool to below 45°C and add the composition corresponding to the example and comparative example. Continue stirring for 5 min. Finally, add arginine to adjust the pH and discharge to obtain the repair essence.

[0045] 1. Application example: Human patch test of skin care lotion Experimental methods: In accordance with the "Cosmetic Safety Technical Specifications" (2015 edition), human patch tests were used to verify the irritation of sensitive skin by this application examples 1-6. The grading criteria for adverse skin reactions are shown in Table 4.

[0046] Thirty volunteers were recruited, including 15 males and 15 females, aged 18-49 years, with an average age of 28.7 years. First, a suitable patch applicator was selected, and a closed patch test method was used. Approximately 25 μL of the test substance was placed in the patch applicator, which was then applied to the volunteer's arm with hypoallergenic adhesive tape. Gently pressing the tape ensured even application to the skin. The test substance was removed after 24 hours. Skin reactions were observed at 0.5, 24, and 48 hours after patch removal. Adverse skin reactions were recorded and are shown in Table 5.

[0047] Table 4. Grading Criteria for Adverse Skin Reactions 0 negative reaction 1 The suspected reaction only showed faint erythema. 2 Weak positive reaction (erythema reaction); erythema, infiltration, edema, and papules may be present. 3 Strong positive reaction (herpes reaction); erythema, infiltration, edema, papules, vesicles; the reaction may extend beyond the test area. 4 Extremely strong positive reaction (confluent herpes simplex reaction); obvious erythema, severe infiltration, edema, confluent herpes simplex; reaction extends beyond the test area. Table 5. Results of adverse skin reactions

[0048] The patch test results showed that no adverse skin reactions such as erythema, infiltration, or edema occurred in Examples 1-6 after 0.5h, 24h, and 48h, indicating that the repair essence prepared in Examples 1-6 and the composition described in Examples 1-6 have good biosafety and are non-irritating and non-sensitizing, providing data support for human trials.

[0049] 2. Photoaging Repair Test in Mice Experimental methods: Ninety male Balb / c mice, 5-6 weeks old and weighing 20-25g, were provided by the Guangdong Provincial Experimental Animal Center. Six mice were randomly divided into 15 groups. The neck and back area (4 cm × 3 cm) of the mice was shaved and dehaired. Then, a UVA+UVB spotlight was used to induce the model. The specific operation was as follows: the groups included: blank group, application group, and control application group.

[0050] Ultraviolet irradiation treatment: The UVA+UVB spotlight irradiation conditions were that the spotlights were arranged in parallel and about 30 cm away from the mice. The mice were preheated for 15 minutes before each irradiation and irradiated for 30 minutes. The UVA dose was 26 J / cm² and the UVB dose was 13 J / cm² throughout the experimental period, and the mice were irradiated daily for 3 consecutive weeks.

[0051] Mouse treatment: Mice were anesthetized 1 hour before irradiation. Control group: No treatment was performed on the hairless neck and back of the mice; Application group and control group: After anesthesia, 2 ml of sample was applied to the hairless neck and back of the mice, dried, and then irradiated with ultraviolet light. The administration frequency was once a day for 21 consecutive days.

[0052] Skin condition monitoring: Mice were anesthetized on days 0 and 21 of the experiment to observe skin changes and assess the photoaging level of the mice's skin.

[0053] The evaluation criteria are as follows: 0-1 points indicate normal appearance or only slight wrinkles; 2-3 points indicate obvious wrinkles; 4-5 points indicate obvious wrinkles and erythema.

[0054] The change in photoaging grade of mouse skin is calculated using the following formula: Change in photoaging grade of mouse skin (E) = Day 21 of photoaging grade of mouse skin - Day 0 of photoaging grade of mouse skin.

[0055] Table 6. Changes in skin photoaging grades in mice (n=6)

[0056] Table 6 shows that: 1) The photoaging grade of mice in Application Examples 1-6 ranged from 1 to 1.8, while the photoaging grade of mice in Comparative Application Examples 1-8 ranged from 2.7 to 3.5. 2) Compared to Application Example 1, Comparative Application Examples 1-4 reduced the effective components of Fucus vesiculosus extract, Matricaria champaca extract, Opuntia ficus-indica stem extract, and Echinacea purpurea extract, resulting in a significantly larger change in the photoaging grade (E) of mice, especially in Comparative Application Example 1. This indicates that Fucus vesiculosus extract may play a major role in anti-photoaging and post-sun exposure repair. 3) Based on the change in the photoaging grade (E) of mice in Comparative Application Examples 5-7, the specific ratio of the four effective components—Fucus vesiculosus extract, Matricaria champaca extract, Opuntia ficus-indica stem extract, and Echinacea purpurea extract—is an important influencing factor in improving post-sun exposure repair. This may be related to the fact that the combination of these four components can achieve a comprehensive and multi-layered synergistic effect, from immediate soothing to deep repair and prevention of photoaging.

[0057] 2. Human body moisturizing and brightening effect test Subjects: 90 volunteers with dry and sensitive skin, aged 18-55, were selected. All volunteers had problems such as dry skin, sensitivity and redness, slight wrinkles, and dull skin tone. They had no serious skin diseases, no history of cosmetic allergies, and had not used any moisturizing, anti-aging, or whitening cosmetics in the week before the experiment.

[0058] Test instruments: Skin moisture meter (to test the moisture content of the stratum corneum of the skin), skin color meter (to test the skin brightness value).

[0059] 3. Test Methods Ninety volunteers were randomly divided into 15 groups of 6 people each. They used the repair essence of Application Examples 1-6 and the control Application Examples 1-8 respectively. A blank control group (which did not use any sample) was also set up. Each group of volunteers used the corresponding sample only on their face, once in the morning and once in the evening, with each application of about 2 mL, for 28 consecutive days.

[0060] The following indicators of facial skin were tested in each group of volunteers before the start of the experiment (day 0) and on day 28: (1) Moisturizing effect: The moisture content of the stratum corneum of the cheek area of ​​the face was tested using a skin moisture meter. Each volunteer was tested 3 times, and the average value T was taken; the percentage change in moisture content % = (T28 - T0) / T0 × 100% (2) Brightening effect: The brightness value (L value) of the cheek area of ​​the face was tested with a skin color tester. The higher the L value, the brighter the skin color. Each volunteer was tested 3 times and the average value L was taken; Brightness L increase value = L28 - L0.

[0061] Table 7 Experimental Results Application Example 1 42.8 4.72 Application Example 2 40.5 4.51 Application Example 3 41.2 4.64 Application Example 4 36.7 4.15 Application Example 5 34.9 4.98 Application Example 6 38.3 4.23 Comparative Application Example 1 20.6 1.25 Comparative Application Example 2 22.5 1.72 Comparative Application Example 3 18.8 1.47 Comparative Application Example 4 21.4 1.53 Comparative Application Example 5 23.6 2.38 Comparative Application Example 6 26.9 2.05 Comparative Application Example 7 26.7 1.86 Comparative Application Example 8 27.5 2.11 Blank control group 3.2 0.28 According to the data in Table 7: 1) In application examples 1-6, the 28-day moisture content improvement rate ranged from 34.9% to 42.8%, and the 28-day skin brightness (L) improvement value ranged from 4.15 to 4.98. Both indicators were higher than those of the control application examples (18.8%-27.5% and 1.25-2.38, respectively). 2) In control application examples 1-4, each lacked one of the four effective components, resulting in a sharp drop in moisture content improvement rate. Among them, control application example 3 (lacking Prunus persica stem extract) had a moisture content improvement rate of only 18.8%, the lowest among all control application examples. This directly confirms that Prunus persica stem extract is the core moisturizing component of this composition. Its strong moisturizing and water-locking ability and long-lasting hydration are the core means to solve the problem of dryness after sun exposure for dry and sensitive skin. Compared to Application Example 1 (lacking Fucus vesiculosus extract), the brightness L value increased by only 1.25, the lowest among all comparative application examples. This directly confirms that Fucus vesiculosus extract is the core brightening component of this composition. Its antioxidant, anti-photoaging, and melanin-inhibiting effects are the core of improving post-sun dullness from the root. Meanwhile, compared to Application Example 2 (lacking Matricaria champaca extract), the brightness increase value was 1.72, which was also significantly lower than Application Example 1. This indicates that the anti-inflammatory and redness-reducing effects and synergistic antioxidant effects of Matricaria champaca extract can effectively improve skin dullness caused by post-sun redness and achieve an auxiliary effect of even brightening. 3) Compared to Application Examples 5-6, the dosage ratio of the core components was adjusted, and the water content increase rate was only 23.6% and 26.9%, significantly lower than Application Examples 1-6. This verifies that the component weight range defined in this invention is the key to achieving synergistic moisturizing effects. Exceeding this range will lead to a significant decrease in the synergistic effect between components. 4) In comparison with application examples 7-8, when trehalose, a conventional moisturizing ingredient, was used to replace the extract of *Fucus vesiculosus*, and calendula extract, a conventional soothing ingredient, was used to replace the extract of *Chaenomeles speciosa*, the water content increase rate was only 26.7% and 27.5%, respectively, which was much lower than that in application example 1. This shows that the combination of the four plant extracts selected in this invention is irreplaceable, and conventional active ingredients cannot achieve the same synergistic moisturizing effect.

[0062] In summary, the 28-day human trial results in Table 7 comprehensively verify the excellent moisturizing and brightening effects of the post-sun repair composition of this invention, clarify the indispensability and criticality of the weight range of the four core components, and verify the scientific validity of the three-level step-by-step repair system designed for the post-sun pain points of dry and sensitive skin. This provides sufficient and reliable human efficacy data to support the industrial application of this composition in skin care products such as post-sun repair sprays, serums, creams, and masks.

[0063] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A post-sun repair composition suitable for dry and sensitive skin, characterized in that, By weight, the active ingredients include: 5-15 parts of Fucus vesiculosus extract, 3-10 parts of chamomile extract, 4-12 parts of Opuntia ficus-indica stem extract, and 2-8 parts of Echinacea purpurea extract.

2. The post-sun repair composition for dry and sensitive skin according to claim 1, characterized in that, By weight, the active ingredients include: 8-12 parts of Fucus vesiculosus extract, 5-8 parts of chamomile extract, 6-10 parts of Opuntia ficus-indica stem extract, and 4-6 parts of Echinacea purpurea extract.

3. The method for preparing the post-sun repair composition suitable for dry and sensitive skin according to claim 1 or 2, characterized in that, Mix all active ingredients thoroughly to obtain the final product.

4. A cosmetic product, characterized in that, The post-sun repair composition for dry and sensitive skin as described in any one of claims 1-2.

5. The cosmetic product according to claim 4, characterized in that, The composition is added to cosmetics in an amount of 0.5-10 wt%.

6. The cosmetic product according to claim 5, characterized in that, The composition is added to cosmetics in an amount of 1-8 wt%.

7. The cosmetic product according to claim 4, characterized in that, The cosmetics also include cosmetic excipients, including moisturizers, emulsifiers, skin moisturizers, thickeners, antioxidants, pH adjusters, and fragrances.

8. The use of the composition according to any one of claims 1-2 in the preparation of cosmetics, characterized in that, The cosmetics mentioned are after-sun repair sprays, repair gels, repair creams, repair masks, or repair serums.

9. The use according to claim 8, characterized in that, The composition is added to cosmetics in an amount of 1-8 wt%.

Images