A deep scalp cleansing essential oil and its preparation method

Abstract

This invention discloses a deep scalp cleansing essential oil and its preparation method, belonging to the field of daily chemical products technology. The deep scalp cleansing essential oil of this invention, by weight, comprises 40-55 parts of a structural building oil phase, 10-20 parts of a sebum-regulating oil phase, 15-35 parts of a spreading-regulating oil phase, 5-10 parts of an interface building component, 2-5 parts of a hydrophilic regulating component, 0.4-2 parts of an active ingredient nanomicelle complex, 0.05-0.2 parts of an antioxidant, and 0.05-0.2 parts of a soothing agent; wherein the spreading-regulating oil phase comprises 5-15 parts of a volatile hydrocarbon oil phase and 10-20 parts of an auxiliary lubricating ester oil phase. Its preparation method includes in-situ self-assembly of the active ingredient nanomicelle complex, surface modification, controlled-rate dropwise addition, and high-speed homogenization nano-sizing steps. The product of this invention has the characteristics of high oxidative stability of active ingredients, strong scalp penetration, and a refreshing feel, making it suitable for deep scalp cleansing and care.

Description

Technical Field

[0001] This invention belongs to the field of daily chemical products technology, specifically relating to a deep scalp cleansing essential oil and its preparation method. Background Technology

[0002] The scalp serves as the soil for hair growth, and its healthy microenvironment directly determines the quality of hair growth. With the fast pace of modern life and increased mental stress, the scalp's microecology is easily imbalanced, leading to increasingly common problems such as excessive oil production and clogged hair follicles, which are difficult to remove with regular washing.

[0003] Deep scalp cleansing is a crucial step in scalp care. Its purpose is to remove accumulated sebum, dead skin cells, and external pollutants from hair follicles, restoring their patency and opening efficient channels for subsequent nourishing and repairing ingredients to penetrate. Currently, oil-based cleansing products, based on the "like dissolves like" principle, are the mainstream choice for achieving deep cleansing. However, in practical applications, these products still face the following technical bottlenecks in pursuing "depth."

[0004] Firstly, it is difficult to simultaneously achieve stability and long-lasting efficacy of active ingredients. Deep cleansing relies on natural active ingredients such as rosemary essential oil, which are rich in unsaturated terpenes and phenols, to exert their antibacterial and metabolic regulating effects. However, these active ingredients are highly sensitive to light, heat, and oxygen, and are prone to oxidative degradation in oil-phase systems, leading to activity decline and even the formation of irritating substances during storage. While existing technologies can delay oxidation by adding antioxidants, they cannot fundamentally solve the problem of long-term stability of active ingredients in the oil phase.

[0005] Secondly, the "depth" and "breadth" of cleaning are limited. Conventional oil-based products mostly use plant oils or mineral oils, which have large molecular volume and high surface tension, resulting in insufficient spreadability and difficulty in effectively penetrating deep into the scalp. The cleaning effect is mostly limited to the scalp surface and inside the hair follicles, and cannot achieve deep cleaning.

[0006] Thirdly, there is a contradiction between "deep cleansing" and "refreshing feel." To enhance degreasing ability, traditional oil-based products often use high-viscosity oil systems, which easily form an oil film residue on the scalp and hair roots after use, resulting in a sticky and heavy feeling. Simply increasing the amount of emulsifier can improve rinsing, but it may damage the scalp barrier function, causing problems such as tightness, dryness, and sensitivity of the scalp after washing.

[0007] To address the aforementioned issues, existing technologies have reported the use of cyclodextrin to encapsulate active ingredients to improve stability, and studies have also explored the use of penetration enhancers to improve the transdermal absorption of active ingredients. However, no effective solution has yet been found that combines active ingredient nanomicelle technology, oil-phase systems with specific spreadability, and mild emulsification processes to simultaneously solve these three major challenges.

[0008] Therefore, there is an urgent need in this field for a deep scalp cleansing technology that can simultaneously solve the problems of active ingredient oxidation and inactivation, insufficient oil phase penetration depth, and oily residue after use, so as to achieve an ideal balance between deep cleansing and scalp comfort. Summary of the Invention

[0009] To address the technical problems of active ingredients being easily oxidized and deactivated, insufficient penetration depth of the oil phase system, and greasy residue after use in existing oil-based deep scalp cleansing products, this invention provides a deep scalp cleansing essential oil and its preparation method.

[0010] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention provides a scalp deep cleansing essential oil, comprising, by weight, the following components: The composition includes: 40-55 parts of structural building oil phase, 10-20 parts of sebum regulating oil phase, 15-35 parts of spreading regulating oil phase, 5-10 parts of interface building component, 2-5 parts of hydrophilicity regulating component; 0.4-2 parts of active ingredient nanomicelle complex, 0.05-0.2 parts of antioxidant and 0.05-0.2 parts of soothing agent; The spreading and conditioning oil phase includes 5-15 parts of volatile hydrocarbon oil phase and 10-20 parts of auxiliary lubricating ester oil phase.

[0011] Specifically, the structure-building oil phase is selected from at least one of caprylic / capric triglyceride (GTCC), squalane, propyl heptyl octanoate, and dioctyl carbonate, serving as the base oil phase carrier of the system to disperse the interface building components and provide a medium environment for the in-situ self-assembly of nanomicelles.

[0012] The sebum-regulating oil phase is selected from at least one of corn oil, olive oil, jojoba oil, and grapeseed oil, and is used to enhance the ability to dissolve deep sebum on the scalp.

[0013] The spreading and regulating oil phase is selected from volatile hydrocarbon oil phase and auxiliary lubricating ester oil phase; the volatile hydrocarbon oil phase is selected from at least one of isohexadecane and isododecane, used to provide instant spreadability and a dry, skin-feeling sensation; the auxiliary lubricating ester oil phase is selected from at least one of isopropyl myristate, isopropyl palmitate, hexadecyl ethylhexanoate, and isononyl isononanoate, used to maintain the lubricity of the system and enhance the solubility of the active ingredients.

[0014] The interface building component is selected from polyglycerol-3 diisostearate, and optionally polyglycerol-4 isostearate and / or polyglycerol-6 distearate, for constructing an ordered interface structure in the oil phase system.

[0015] The hydrophilic adjustment component is selected from at least one of polyglycerol-10 laurate, polyglycerol-10 stearate, and polyglycerol-10 oleate, and is used to improve the product's emulsification performance in water contact, thereby achieving a refreshing rinse.

[0016] The active ingredient in the active ingredient nanomicelle complex is at least one selected from rosemary essential oil, tea tree essential oil, peppermint essential oil, and lavender essential oil. The nanomicelles in the active ingredient nanomicelle complex are formed by in-situ self-assembly of an amphiphilic block copolymer and the active ingredient; the amphiphilic block copolymer is selected from at least one selected from vitamin E polyethylene glycol succinate (TPGS), polyethylene glycol-polylactic acid-glycolic acid copolymer (PEG-PLGA), and polyethylene glycol-polycaprolactone (PEG-PCL); the mass ratio of the active ingredient to the amphiphilic block copolymer is 1:2 to 1:5.

[0017] Furthermore, the surface of the active ingredient nanomicelle composite is coated with a surface modification layer, which is formed by a surface modifier; the surface modifier is selected from at least one of polyglycerol-3 diisostearate, polyglycerol-6 polyricinoleate, and polyglycerol-4 isostearate. The surface modification layer serves to enhance the dispersion stability of the nanomicelles in the oil phase system and prevent micelle aggregation.

[0018] The antioxidant is tocopherol, which is used to protect the unsaturated components in the oil phase matrix.

[0019] The soothing agent is bisabolol, used to reduce potential irritation and improve user comfort.

[0020] The scalp deep-cleansing essential oil of this invention is a clear, transparent, homogeneous oily liquid, containing no added aqueous phase. Its oil phase system contains nano-sized droplets, and the volumetric particle size of the dispersed phase was measured by laser particle size analysis. D 90 The wavelength range is 200~460nm, and the polydispersity index (PDI) is ≤0.3.

[0021] Secondly, the present invention provides a method for preparing the above-mentioned deep scalp cleansing essential oil, comprising the following steps: S1. Dissolve the active ingredient and the amphiphilic block copolymer in anhydrous ethanol at a mass ratio of 1:2 to 1:5 to obtain a pre-assembled solution; slowly add the pre-assembled solution dropwise to the structure building oil phase preheated to 40 to 50°C under stirring conditions, and continue stirring for 15 to 20 minutes after the addition is complete, so that the amphiphilic block copolymer can self-assemble in situ in the oil phase to form nano micelles carrying the active ingredient. S2. Add a surface modifier to the system obtained in step S1 and stir at 35~45℃ for 10~15 minutes to coat the surface modifier onto the surface of the active nanomicelle composite. S3. Adjust the system obtained in step S2 to 30~40℃, add hydrophilic adjustment components, antioxidants and soothing agents, and stir at 1500~2500rpm for 8~12 minutes to obtain a functionalized oil phase mixture; S4. Under the condition of keeping warm at 30~40℃, volatile hydrocarbon oil phase is added dropwise to the functionalized oil phase mixture obtained in step S3 at a controlled rate of 1.5~2.5mL / min, and the mixture is continuously stirred to obtain the initial emulsified oil phase. S5. Add auxiliary lubricating ester oil phase and sebum conditioning oil phase to the initial emulsified oil phase obtained in step S4, stir evenly, cool to room temperature, and perform high-speed homogenization to obtain nano-dispersed scalp deep cleansing essential oil; the process parameters of the high-speed homogenization are: rotation speed 8000~15000rpm, processing time 3~8 minutes; S6. Fill the nano-dispersed scalp deep cleansing essential oil obtained in step S5 into a brown glass bottle and seal it to obtain the finished product.

[0022] The preparation method described in this invention utilizes a synergistic process of in-situ self-assembly in the oil phase, surface modification, controlled-rate drop addition, and high-speed homogenization to achieve stable dispersion of nanomicelles in the oil phase system, forming a uniform nanoscale dispersion structure with excellent chemical stability of the active ingredients.

[0023] The beneficial effects of this invention are as follows: 1. This invention utilizes the synergistic effect of in-situ self-assembly of amphiphilic block copolymers and surface modification to encapsulate active ingredients in a hydrophobic core of nanomicelles and form a stable nanoscale dispersion system. This effectively isolates the active ingredients from oxygen, significantly improves the oxidative stability of the active ingredients, and solves the technical problem of easy oxidation and deactivation of active ingredients in traditional oil-based products.

[0024] 2. This invention, through the synergistic effect of nanomicelle structure and spreading-regulating oil phase, endows the product with excellent spreadability and penetration ability, enabling the active ingredients to effectively penetrate deep into the scalp, thus solving the technical problems of poor spreadability and insufficient penetration depth of traditional oil-based products.

[0025] 3. This invention, through the synergistic effect of hydrophilic regulating components and surface modification layers, endows the anhydrous oil phase system with water emulsification properties. The product can be rapidly emulsified upon contact with water, and rinses cleanly without residue, effectively improving the problems of greasy skin feel and obvious residue of traditional oil-based products.

[0026] 4. This invention utilizes the synergistic effect of in-situ self-assembly process and high-speed homogenization technology, that is, the amphiphilic block copolymer is in-situ self-assembled in the oil phase to form nanomicelles, avoiding the agglomeration of nanomicelles caused by the drying process in traditional powder methods. At the same time, the strong shear force of high-speed homogenization achieves submicron-level uniform dispersion, thus achieving the unity of nanoscale uniform dispersion and efficient retention of active ingredients.

[0027] 5. This invention constructs a stable nano-dispersion system by optimizing the combination of the oil phase and the interface components, resulting in products with excellent centrifugal stability. Attached Figure Description

[0028] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0029] Figure 1 This is a flowchart illustrating the preparation process of the deep scalp cleansing essential oil of the present invention. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings, specific embodiments, and comparative examples, but the scope of protection of the present invention is not limited thereto. Unless otherwise specified, all parts below are parts by weight.

[0031] The table below lists the composition (parts by weight) of the scalp deep cleansing essential oil formulations in Examples 1-8: Formulation composition of Examples 1-8

[0032] Example 1 The preparation steps are as follows: S1. Dissolve the active ingredient and the amphiphilic block copolymer in anhydrous ethanol at a specified mass ratio according to the formulation to obtain a pre-assembled solution; slowly add the pre-assembled solution dropwise to the structure building oil phase preheated to 45°C under stirring conditions, and continue stirring for 15 minutes after the addition is complete, so that the amphiphilic block copolymer can self-assemble in situ in the oil phase to form nano micelles carrying the active ingredient.

[0033] S2. Add a surface modifier to the system obtained in step S1 and stir at 40°C for 12 minutes to coat the surface modifier onto the surface of the active nanomicelle composite.

[0034] S3. Adjust the system obtained in step S2 to 35°C, add hydrophilic adjustment components, tocopherol, and bisabolol, and stir at 2000 rpm for 10 minutes to obtain a functionalized oil phase mixture.

[0035] S4. Under the condition of keeping warm at 35℃, volatile hydrocarbon oil phase is added dropwise at a controlled rate of 2.0 mL / min to the functionalized oil phase mixture obtained in step S3, and the mixture is continuously stirred to obtain the primary emulsion oil phase.

[0036] S5. Add auxiliary lubricating ester oil phase and sebum conditioning oil phase to the initial emulsified oil phase obtained in step S4, stir evenly, cool to room temperature, and perform high-speed homogenization treatment (speed 12000 rpm, treatment time 5 minutes) to obtain nano-dispersed scalp deep cleansing essential oil.

[0037] S6. Fill the nano-dispersed scalp deep cleansing essential oil obtained in step S5 into a brown glass bottle and seal it to obtain the finished product.

[0038] The method of using this product is as follows: Optionally, after applying a warm towel to the scalp for 2-3 minutes, take 3-5 drops of this product into the palm of your hand and gently massage the areas of the scalp with excessive oil secretion for 3-5 minutes with your fingertips. Leave it on for 5-10 minutes, emulsify with warm water and rinse, then proceed with your regular shampooing.

[0039] Example 2 The difference from Example 1 is that the active ingredient is a compound system of 0.2 parts rosemary essential oil and 0.1 parts tea tree essential oil. The preparation method is the same as in Example 1.

[0040] Example 3 The difference from Example 1 is that PEG-PLGA was used instead of TPGS for the amphiphilic block copolymer. The preparation method is the same as in Example 1.

[0041] Example 4 The difference from Example 1 is that the mass ratio of the active ingredient to the amphiphilic block copolymer is 1:2. The preparation method is the same as in Example 1.

[0042] Example 5 The difference from Example 1 is that the mass ratio of the active ingredient to the amphiphilic block copolymer is 1:5. The preparation method is the same as in Example 1.

[0043] Example 6 The difference from Example 1 is that the active ingredient nanomicelle composite is 0.4 parts. The preparation method is the same as in Example 1.

[0044] Example 7 The difference from Example 1 is that the total amount of the active ingredient nanomicelle complex is 2 parts. The preparation method is the same as in Example 1.

[0045] Example 8 The difference from Example 1 is that the total amount of the oil phase used for spreading and adjustment is 15 parts. The preparation method is the same as in Example 1.

[0046] Table 2 lists the composition (parts by weight) of the scalp deep cleansing essential oil formulations for Comparative Examples 1-8: Table 2. Formulation composition of Comparative Examples 1-8

[0047] Comparative Example 1 The difference from Example 1 is that TPGS is not used, and the active ingredient is directly added to the oil phase. Step S1 is omitted in the preparation method.

[0048] Comparative Example 2 The formula is the same as in Example 1. The difference in preparation method compared to Example 1 is that step S2 is omitted.

[0049] Comparative Example 3 The difference from Example 1 is that there is no volatile hydrocarbon oil phase (isohexadecane). Step S4 is omitted in the preparation method.

[0050] Comparative Example 4 The difference from Example 1 is that the hydrophilicity-modifying component (polyglycerol-10 laurate) is absent. This component is not added in step S3 of the preparation method.

[0051] Comparative Example 5 The formulation is the same as in Example 1. The difference in preparation method from Example 1 is that step S1 is changed to the traditional powder dispersion method (first prepare an aqueous solution of nanomicelles, then freeze-dry, and finally disperse the powder in the oil phase).

[0052] Comparative Example 6 The formula is the same as in Example 1. The difference in preparation method compared to Example 1 is that step S5 is replaced with conventional stirring (800 rpm, stirring time 8 minutes).

[0053] Comparative Example 7 The difference from Example 1 is that Tween 80 was used instead of polyglycerol-3 diisostearate as the interface building component. The preparation method is the same as in Example 1.

[0054] Comparative Example 8 The difference from Example 1 is that mineral oil was used instead of GTCC and squalane in the oil phase of the structure. The preparation method is the same as in Example 1.

[0055] Performance testing 1. Determination of average particle size and polydispersity index (PDI) Take 0.1g of each sample prepared in the examples and comparative examples, and use a Malvern Zetasizer Nano ZS90 nanoparticle size and Zeta potential analyzer. Set the refractive index to 1.45 and the equilibration time to 120 seconds, and measure the average particle size and polydispersity index (PDI) of each sample under constant temperature conditions of 25℃. Each sample is measured 3 times and the average value is taken.

[0056] It should be noted that, in this invention, the average particle size refers to the Z-Average value measured by the dynamic light scattering method, which reflects the overall particle size level of the system; D 90 This refers to the particle size value corresponding to a cumulative particle size distribution reaching 90%, reflecting the upper limit of large particle distribution in the system. In uniformly dispersed nanoscale systems, D 90 Typically, it is 1.2 to 1.5 times the average particle size. The test results are shown in Table 1.

[0057] 2. Centrifugal stability test Take 10 mL of each sample prepared in the examples and comparative examples and place them in a centrifuge tube. Centrifuge at 4000 r / min for 30 minutes. After removing the tube, visually observe whether the sample shows layering, turbidity, or precipitation, and record the changes in appearance. The test results are shown in Table 1.

[0058] 3. Determination of emulsification time upon contact with water Take 1 g of each sample prepared in the examples and comparative examples, and drop them into a beaker containing 100 mL of deionized water. Place the beaker on a magnetic stirrer and stir at a constant speed of 200 rpm. Start timing from the moment the sample is completely dropped into the water surface until no obvious oil film floats on the water surface and a uniform emulsified dispersion is formed. Record the time (in seconds). If complete emulsification is not achieved after 5 minutes, record it as ">300 seconds". This test is used to evaluate the product's emulsification ability upon contact with water, directly reflecting the refreshing feeling after rinsing. The test results are shown in Table 1.

[0059] 4. Basic physicochemical performance tests Peroxide value: The determination was performed using the titration method as specified in GB 5009.227-2023 National Food Safety Standard - Determination of Peroxide Value in Food. Acid value: Determined by cold solvent indicator titration method according to GB 5009.229-2025 National Food Safety Standard - Determination of Acid Value in Food; Saponification value: The saponification value was determined in accordance with GB / T 5534-2024 "Determination of Saponification Value of Animal and Vegetable Oils"; the test results are shown in Table 2.

[0060] 5. Accelerated oxidation stability test and active ingredient retention rate determination Accelerated oxidation stability test: 20 g of each sample prepared in the examples and comparative examples were placed in brown glass bottles, sealed, and placed in a 60℃ constant temperature oven. Samples were taken on day 0, day 7, and day 14, and the trend of peroxide value change was measured according to GB 5009.227-2023 to analyze the difference in oxidation rate. The test results are shown in Table 3.

[0061] Determination of active ingredient retention: 20 g of each sample prepared in Examples 1-8 and Comparative Examples 1, 2, 5, and 6 were sealed in brown glass bottles and placed in a 60℃ constant temperature oven for accelerated aging for 14 days. Samples were taken on day 0 and day 14, and the peak area of ​​1,8-cineole, the marker component in rosemary essential oil, was determined by gas chromatography-mass spectrometry (GC-MS).

[0062] Chromatographic conditions: HP-5MS capillary column (30m×0.25mm×0.25μm); injection port temperature 250℃; temperature program: 50℃ for 2 min, increase to 150℃ at 5℃ / min, then increase to 280℃ at 10℃ / min and hold for 5 min; carrier gas was high-purity helium, flow rate 1.0 mL / min; split ratio 20:1.

[0063] The retention rate of 1,8-cineole was calculated using the following formula: Retention rate (%) = (peak area of ​​1,8-cineole after 14 days of accelerated aging / initial peak area of ​​1,8-cineole) × 100%. The test results are shown in Table 3.

[0064] 6. Evaluation of the greasiness felt by human senses Twenty healthy volunteers were selected, and the inner forearms were cleaned. 0.2 g of each example and comparative sample was applied to both sides, and massaged in circular motions 20 times until absorbed. One minute and five minutes after application, volunteers blindly rated the oiliness of the applied area on a 10-point scale (0 = extremely oily and not breathable; 10 = extremely refreshing and burden-free). The test results are shown in Table 3.

[0065] Table 1 Particle size, stability and emulsifying properties

[0066] Table 2 Basic physicochemical properties results

[0067] Table 3 Accelerated oxidation stability, active ingredient retention and sensory evaluation

[0068] I. Physical Performance Analysis As shown in Table 1, the average particle size of Examples 1-8 was 220.5-285.6 nm, D90 was 308.3-448.5 nm, and PDI was 0.15-0.25, indicating that all examples formed a uniform submicron-scale dispersion system after high-speed homogenization. Example 7 had the smallest average particle size and lowest PDI, with an average particle size of 220.5 nm and a PDI of 0.15, indicating that increasing the amount of amphiphilic block copolymer is beneficial for forming denser and more uniform nanomicelles in the oil phase, which are more resistant to structural damage under high shear force. Example 5 had an average particle size of 228.4 nm and a PDI of 0.16, with particle size and distribution second only to Example 7, proving that increasing the proportion of amphiphilic block copolymer helps to construct a more stable nanomicelle shell. Example 6 showed an average particle size of 285.6 nm and a PDI of 0.25. Although the particle size was slightly large, it was still within the submicron range, demonstrating that 0.4 parts of the active ingredient nanomicelle composite could still effectively construct a nanodispersed structure. Example 8 showed an average particle size of 250.2 nm, which was close to that of Example 1, indicating that the amount of spreading oil phase had little effect on the micelle particle size.

[0069] Comparative Example 1, without the addition of the amphiphilic block copolymer, had the active ingredient directly added to the oil phase, failing to form a nanomicelle structure and resulting in unmeasurable particle size. Comparative Example 2, omitting the surface modification step, increased the particle size to 328.5 nm and the PDI to 0.33. Comparative Example 5, using a traditional powder dispersion method, significantly increased the particle size to 412.6 nm and the PDI to 0.42. Comparative Example 7, using Tween 80 instead of polyglycerol-3 diisostearate, increased the particle size to 385.4 nm and the PDI to 0.38. These results indicate that the surface modification layer plays a crucial role in maintaining the dispersion stability of nanomicelles in the oil phase and preventing micelle aggregation. The in-situ self-assembly process yields smaller and more uniform nano-dispersed structures compared to the traditional powder method. The synergistic effect of the polyglycerol ester interface building components and the ester structure building oil phase plays a vital role in forming the nanoscale dispersed structure. Comparative Example 6, using conventional stirring, achieved a particle size of 445.2 nm and a PDI as high as 0.45, demonstrating that high-speed homogenization with strong shear force is a necessary means to achieve submicron-level uniform dispersion.

[0070] Centrifugal stability tests showed that Examples 1-5, 7, and 8 remained clear and transparent, without stratification or precipitation, after centrifugation at 4000 r / min for 30 minutes. Example 6 showed slight turbidity, which was attributed to the fact that the total amount of the active ingredient nanomicelle complex in this example was only 0.4 parts, while the surface modifier was relatively excessive. The free modifier under centrifugal force underwent slight self-aggregation, but the degree was significantly less than the precipitation observed in the comparative examples and remained within an acceptable range. Comparative Example 1 showed stratification, Comparative Examples 2, 5, 6, and 7 showed significant precipitation, and Comparative Example 8 showed slight turbidity. These results indicate that the nanomicelle structure formed by the amphiphilic block copolymer, the surface modification layer, and the synergistic effect of polyglycerol-3 diisostearate and the oil phase of the structure-building phase play a crucial role in maintaining the stability of the system.

[0071] Emulsification time tests upon contact with water showed that the emulsification times for Examples 1-8 were 23-35 seconds. Example 7 had the shortest emulsification time at 23 seconds, Example 6 had a slightly longer emulsification time of 32 seconds, and Example 8 had an emulsification time of 35 seconds. Comparative Example 4 failed to emulsify completely even after more than 300 seconds, Comparative Example 2 took 55 seconds, Comparative Example 7 took 75 seconds, and Comparative Example 8 took 60 seconds. These results indicate that polyglycerol-10 laurate is the key component that imparts the self-emulsifying ability of the anhydrous oil phase system upon contact with water, and the type of surface modification layer and the type of oil phase structure also have a significant impact on emulsification performance.

[0072] II. Basic Physicochemical Properties Analysis Table 2 shows that the acid values ​​of Examples 1-8 were 0.7-0.9 mg KOH / g, the initial peroxide values ​​were 2.3-2.8 meq / kg, and the saponification values ​​were 182-187 mg KOH / g, all meeting the quality requirements for cosmetic oils. Comparative Example 1 had a relatively high initial peroxide value of 3.2 meq / kg, indicating that the nanomicelle encapsulation played an important role in inhibiting the initial oxidation of the active ingredient. Comparative Example 7 had a slightly higher acid value (1.2 mg KOH / g), possibly related to the presence of trace amounts of free fatty acids in Tween 80. The saponification value of Comparative Example 8 was 192 mg KOH / g, which is attributed to the different chemical structures of mineral oil and ester oil phases.

[0073] The difference in saponification value mainly stems from the molecular weight difference of different oil components. Comparative Example 8 uses mineral oil, which does not contain ester groups, but the formula still contains saponifiable components such as corn oil, so the saponification value is still at a certain level.

[0074] In addition, the hygiene indicators of Examples 1-8 (including total bacterial count, mold and yeast, fecal coliforms, Staphylococcus aureus, Pseudomonas aeruginosa, lead, mercury, and arsenic) all met the requirements of the "Cosmetic Safety Technical Specifications" (2015 edition) after testing.

[0075] III. Accelerated Oxidation Stability and Active Product Retention Rate Analysis Table 3 shows that after accelerated aging at 60℃ for 14 days, the peroxide values ​​of Examples 1-8 were 5.3-6.6 meq / kg, significantly lower than those of the comparative examples. Example 7 had the lowest peroxide value at 5.3 meq / kg, Example 5 had 5.5 meq / kg, and Example 6 had 6.6 meq / kg. This indicates a positive correlation between the total amount of the active ingredient nanomicelle complex and the mass ratio of the active ingredient to the amphiphilic block copolymer and the protective effect of the active ingredient; that is, the higher the total amount of the complex and the higher the relative proportion of the polymer, the more significant the protective effect. The retention rate of the active ingredient showed that the retention rate of 1,8-cineole in Examples 1-8 was 82.5%-91.5%, with Example 7 having a retention rate as high as 91.5%, Example 5 having a retention rate of 90.3%, and Example 6 having a retention rate of 82.5%. The retention rate of Comparative Example 1 was only 52.3%, Comparative Example 2 was 75.5%, Comparative Example 5 was 68.5%, and Comparative Example 6 was 65.8%. The retention rates of Comparative Examples 3 and 4 were 85.6% and 87.2%, respectively, which were close to those of the Examples. This indicates that the absence of volatile hydrocarbon oil phase and hydrophilic conditioning components mainly affects the spreadability and rinseability of the product, and has little impact on the chemical stability of the active ingredient.

[0076] The above data indicate that the in-situ self-assembly process of amphiphilic block copolymers used in this invention, combined with a surface modification layer, provides dual protection for the thermosensitive active ingredient by physically isolating the active ingredient from oxygen through the nanomicelle core and further blocking the penetration of oxygen molecules into the nanomicelle core through the surface modification layer. The in-situ self-assembly process avoids the damage to the nanomicelle structure and premature oxidation of the active ingredient caused by the drying process in traditional powder methods. The retention rate of Comparative Example 6, achieved with conventional stirring, was only 65.8%, significantly lower than that of Example 1, demonstrating that the strong shear force of high-speed homogenization is beneficial for achieving uniform dispersion before the active ingredient degrades, while conventional stirring cannot effectively disperse the nanomicelles.

[0077] IV. Evaluation and Analysis of Human Sensory Sensation of Greasiness Table 3 shows that the refreshing feeling scores of Examples 1-8 ranged from 8.5 to 9.4, indicating a refreshing and non-greasy feel. Example 7 scored as high as 9.4, Example 5 scored 9.3, Example 8 scored 8.5, and Example 6 scored 8.7. Comparative Example 4 had the lowest score at only 4.1, followed by Comparative Example 2 at 6.8, Comparative Example 7 at 6.2, and Comparative Example 8 at 6.3. Comparative Example 1 scored 8.3, indicating a low retention rate of active ingredients but a acceptable skin feel, suggesting that the nanomicelle encapsulation mainly affects the stability of active ingredients and has a relatively small impact on skin feel.

[0078] The refreshing feel of the embodiment is mainly attributed to three aspects: First, the nanomicelle structure increases the contact area between the oil phase and the skin, which is conducive to rapid spread and absorption and reduces local accumulation; Second, polyglycerol-10 laurate gives the system the ability to self-emulsify in water, which can quickly emulsify when in contact with a small amount of water on the skin surface or when washed with water afterward, reducing the feeling of oil residue; Third, the surface modification layer enhances the uniformity of dispersion of nanomicelles in the oil phase and avoids oil accumulation.

[0079] The above comparison results confirm that the synergistic effect of the component selection and preparation process of the present invention simultaneously solves three major technical problems: oxidation and deactivation of active ingredients, insufficient penetration depth of the oil phase, and greasy residue after use, thus achieving the expected technical effect.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A scalp deep cleansing essential oil characterized in that, Based on parts by weight, it includes the following components: The composition includes 40-55 parts of structural building oil phase, 10-20 parts of sebum regulating oil phase, 15-35 parts of spreading regulating oil phase, 5-10 parts of interface building component, 2-5 parts of hydrophilic regulating component, 0.4-2 parts of active ingredient nanomicelle complex, 0.05-0.2 parts of antioxidant and 0.05-0.2 parts of soothing agent; The spreading and conditioning oil phase includes 5-15 parts of volatile hydrocarbon oil phase and 10-20 parts of auxiliary lubricating ester oil phase.

2. The scalp deep cleansing essential oil according to claim 1, wherein, The oil phase of the structure is selected from at least one of caprylic / capric triglyceride, squalane, propylheptyl caprylate, and dioctyl carbonate.

3. The scalp deep cleansing essential oil of claim 1, wherein, The sebum-regulating oil phase is selected from at least one of corn oil, olive oil, jojoba oil, and grapeseed oil.

4. The scalp deep cleansing essential oil of claim 1, wherein, The volatile hydrocarbon oil phase is selected from at least one of isohexadecane and isododecane; the auxiliary lubricating ester oil phase is selected from at least one of isopropyl myristate, isopropyl palmitate, hexadecyl ethylhexanoate, and isononyl isononanoate.

5. The scalp deep cleansing essential oil of claim 1, wherein, The interface building component comprises polyglycerol-3 diisostearate, and optionally polyglycerol-4 isostearate and / or polyglycerol-6 distearate; the hydrophilicity regulating component is selected from at least one of polyglycerol-10 lauryl ester, polyglycerol-10 stearate, and polyglycerol-10 oleate.

6. The scalp deep cleansing essential oil of claim 1, wherein, The active ingredient in the active ingredient nanomicelle complex is at least one of rosemary essential oil, tea tree essential oil, peppermint essential oil, and lavender essential oil.

7. The scalp deep cleansing essential oil of claim 6, wherein, The nanomicelles in the active ingredient nanomicelle complex are formed by in-situ self-assembly of an amphiphilic block copolymer and an active ingredient; the amphiphilic block copolymer is selected from at least one of vitamin E polyethylene glycol succinate, polyethylene glycol-polylactic acid-glycolic acid copolymer, and polyethylene glycol-polycaprolactone; the mass ratio of the active ingredient to the amphiphilic block copolymer is 1:2 to 1:

5.

8. The scalp deep cleansing essential oil of claim 7, wherein, The surface of the active ingredient nanomicelle complex is further coated with a surface modification layer, which is formed by a surface modifier; the surface modifier is selected from at least one of polyglycerol-3 diisostearate and polyglycerol-6 polyricinoleate.

9. The scalp deep cleansing essential oil of claim 1, wherein, The antioxidant is tocopherol; the soothing agent is bisabolol.

10. A method of preparing the scalp deep cleansing essential oil according to claim 8, characterized by, Includes the following steps: S1. Dissolve the active ingredient and the amphiphilic block copolymer in anhydrous ethanol at a mass ratio of 1:2 to 1:5 to obtain a pre-assembled solution; The pre-assembly liquid was slowly added dropwise to the structure building oil phase preheated to 40-50°C under stirring. After the addition was complete, stirring was continued for 15-20 minutes to obtain the S1 system. S2. Add a surface modifier to the system in step S1 and stir at 35~45℃ for 10~15 minutes to obtain the system in step S2; S3. Adjust the temperature of the system in step S2 to 30~40℃, add hydrophilic adjustment components, antioxidants and soothing agents, and stir at 1500~2500 rpm for 8~12 minutes to obtain a functionalized oil phase mixture; S4. Under the condition of keeping warm at 30~40℃, volatile hydrocarbon oil phase is added dropwise to the functionalized oil phase mixture obtained in step S3 at a controlled rate of 1.5~2.5mL / min, and the mixture is continuously stirred to obtain the initial emulsified oil phase. S5. Add auxiliary lubricating ester oil phase and sebum conditioning oil phase to the initial emulsified oil phase obtained in step S4, stir evenly, cool to room temperature, and perform high-speed homogenization to obtain nano-dispersed scalp deep cleansing essential oil; the process parameters of the high-speed homogenization are: rotation speed 8000~15000rpm, processing time 3~8 minutes; S6. Fill the nano-dispersed scalp deep cleansing essential oil obtained in step S5 into a brown glass bottle and seal it to obtain the finished product.

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