Essence oil and preparation method thereof

Abstract

The invention relates to the field of emulsification, in particular to essence oil and a preparation method thereof. The preparation raw materials comprise base oil, functional oil, an antioxidant, a humectant, a plant extractant and an auxiliary agent. According to the system provided by the invention, through gradient layering of high and low polar oil phases and interface synergistic steady-state barrier design, a moderate polar matrix layer consisting of caprylic / capric triglyceride (MCT) and ethylhexyl stearate in a continuous phase and a low polar dispersion layer consisting of pentaerythritol tetra (ethylhexanoate) ester and diisostearyl malate are formed; the two phases are in stable transition through a micro-layer interface film formed by oil-soluble lecithin and octyldodecanol. According to the structure, through intermolecular Van der Waals force, hydrogen bond weak interaction and polarity matching, ordered arrangement of different polar components under the nanoscale is achieved, and migration and oxidation instability of oil phase active components are remarkably inhibited.

Description

Technical Field

[0001] This invention relates to the field of emulsification, and more particularly to an essential oil and its preparation method. Background Technology

[0002] Existing skin-care oils are typically based on single-phase oil systems, using a blend of plant oils and synthetic esters to improve skin feel. However, the solubility of oil-soluble active ingredients in traditional systems is limited, making them susceptible to precipitation due to polarity differences. Furthermore, they are prone to problems such as turbidity, layering, or oxidative discoloration during storage. Simultaneously, achieving a better skin feel and spreadability often requires a high proportion of low-polarity oils, resulting in insufficient active ingredient carrying capacity and skin absorption.

[0003] In recent years, with the development of the "multiphase synergistic system" concept, utilizing polarity differences to construct a layered steady-state structure has become a new direction for improving the stability of oil-phase systems. However, existing technologies lack systematic solutions for the active loading, antioxidant stability, and skin feel balance in skin essence oil systems. Therefore, it is necessary to develop an essence oil system with a multipolar steady-state structure that also possesses antioxidant and repairing effects. Summary of the Invention

[0004] This invention aims to provide a micro-layer stabilized skin essence oil with antioxidant and repairing effects and its preparation method. Through multipolar oil phase synergy, phospholipid structure stability and multidimensional antioxidant system design, it achieves high activity load, excellent antioxidant properties and comfortable skin feel.

[0005] To address the above problems, the present invention provides an essential oil whose raw materials include: base oil, functional oil, antioxidant, moisturizer, plant extract, and auxiliary agents.

[0006] Preferably, the base oil is ethylhexyl stearate.

[0007] Preferably, the functional oil is diisostearyl malate, caprylic / capric triglyceride, isononyl isononanoate, and lecithin.

[0008] Preferably, the antioxidant is coenzyme Q10, ascorbate tetraisopalmitate, tocopheryl acetate, or pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester.

[0009] Preferably, the moisturizer is Hyacolor™-LA oil-dispersible sodium hyaluronate and ceramide EOP.

[0010] Preferably, the plant extract is camellia (Camellia japonica) flower extract, Tubermelanosporum extract, safflower (Carthamus tinctorius) flower extract, and patchouli (Pogostemoncablin) leaf extract.

[0011] Preferably, the adjuvant is pentaerythritol tetra(ethylhexanoate), octyldodecyl alcohol, or orange peel oil.

[0012] More preferably, the mass ratio of diisostearyl malate, caprylic / capric triglyceride, isononyl isononanoate, and lecithin is 8:8:5:0.5.

[0013] More preferably, the mass ratio of the camellia (Camellia japonica) flower extract, the tuber melanosporum extract, the safflower (Carthamus tinctorius) flower extract, and the patchouli (Pogostemon cablin) leaf extract is 3:1:3:1.

[0014] The preparation method of the essential oil is as follows: Ethylhexyl stearate, pentaerythritol tetra(ethylhexanoate), caprylic / capric triglyceride, and isononyl isononanoate are added to a reaction vessel and stirred at 70°C for 15 min until a clear homogeneous solution is formed. Diisostearyl malate and lecithin were added at 50°C and stirred for 20 min to form a uniform microlayer dispersion system. Cool the temperature to below 45°C, then add ubiquinone, ascorbate tetraisopalmitate, tocopheryl acetate and pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester in sequence, and stir for 10 min until completely dissolved. Add Hyacolor™-LA, ceramide EOP and various plant extracts at a temperature below 40°C, stir well, and let stand for 30 minutes to remove bubbles; After cooling to room temperature, add orange peel oil and patchouli leaf extract, stir well, filter to remove bubbles, and you will get a clear orange-yellow essential oil product.

[0015] The system provided by this invention utilizes a gradient stratification of high and low polarity oil phases and a synergistic interfacial steady-state barrier design to form a medium-polarity matrix layer composed of caprylic / capric triglyceride (MCT) and ethylhexyl stearate in a continuous phase, and a low-polarity dispersion layer composed of pentaerythritol tetra(ethylhexanoate) and diisostearyl malate. The two phases are stably transitioned between each other by a "micro-interface film" formed by oil-soluble lecithin and octyldodecyl alcohol. This structure achieves the ordered arrangement of different polarity components at the nanoscale through intermolecular van der Waals forces, weak hydrogen bonding interactions, and polarity matching, significantly suppressing the migration and oxidative instability of the active components in the oil phase.

[0016] Secondly, this invention introduces an oil-soluble sodium hyaluronate dispersion (Hyacolor™-LA) into the oil phase system, giving the system a water-in-oil hydration effect. This dispersion forms "quasi-aqueous phase domains" between microlayers, which can adsorb and slowly release water molecules in the stratum corneum of the skin, thereby improving the moisturizing properties and skin barrier repair capabilities of the oil phase essence.

[0017] Ubiquinone (coenzyme Q10) and ascorbate tetraisopalmitate (VC-IP) form an oil-phase redox pair system, which generates an electron transfer channel during free radical capture, synergistically scavenging ROS and maintaining the mitochondrial activity of skin cells; Tocopherol acetate and pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester synergistically form a lipid-phase antioxidant protective barrier, terminating the peroxidation chain reaction through hydrogen donor action; The plant essence fraction containing extracts of black truffle, camellia, and hybrid rose provides natural polyphenols, flavonoids, and triterpenoid antioxidant components, forming a multi-level free radical scavenging channel with the aforementioned synthetic antioxidant system.

[0018] In addition, the stability of the interfacial structure also stems from the synergistic effect of the molecular volume and branched configuration of pentaerythritol tetra(ethylhexanoate) ester and diisostearyl malate. This configuration can form a quasi-liquid crystal dispersion domain in the oil phase, reducing friction and interfacial tension within the system, thus giving the essence oil a light, silky, and quick-spreading feel on the skin.

[0019] Therefore, the micro-layer stable essence oil system of the present invention is not only superior to the traditional oil-soluble system in terms of physicochemical stability (such as avoiding VC-IP precipitation and ubiquinone degradation), but also achieves a triple synergistic effect of anti-oxidation, repair and moisturizing in terms of efficacy. According to actual tests, the main active content retention rate of the system is >95% after 90 days of storage, the light transmittance does not decrease significantly, and there is no layering phenomenon in appearance. Attached Figure Description

[0020] Figure 1 These are comparative images of the subjects' faces after using the essence oil from Example 1 for 7 days. Detailed Implementation

[0021] The following detailed description is based on specific embodiments.

[0022] Example 1 This embodiment provides an essential oil, the raw materials for which are prepared include: 40 parts ethylhexyl stearate; 10 parts pentaerythritol tetra(ethylhexanoate); 8 parts diisostearyl malate; 8 parts caprylic / capric triglyceride; 5 parts isononyl isononanoate; 0.5 parts lecithin; 0.5 parts ubiquinone (coenzyme Q10); 1 part ascorbate tetraisopalmitate (VC-IP); 0.5 parts tocopheryl acetate (VE-Ac); 0.2 parts pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid); 0.5 parts Hyacolor™-LA oil-dispersible sodium hyaluronate; 0.2 parts ceramide EOP (oil-dispersible); 0.3 parts Camellia japonica flower extract; 0.1 parts Tubermelanosporum extract; 0.3 parts Carthamus tinctorius flower extract; 0.3 parts Pogostemon cablin. 0.1 part of cablin leaf extract; 0.5 part of octyl-dodecyl alcohol; 0.1 part of orange peel oil.

[0023] The preparation method of the essential oil is as follows: Ethylhexyl stearate, pentaerythritol tetra(ethylhexanoate), caprylic / capric triglyceride, and isononyl isononanoate are added to a reaction vessel and stirred at 70°C for 15 min until a clear homogeneous solution is formed; diisostearyl malate and lecithin are added at 50°C and stirred for 20 min to form a uniform microlayer dispersion system; the temperature is lowered to below 45°C, and ubiquinone, ascorbate tetraisopalmitate, tocopheryl acetate, and pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester are added sequentially and stirred for 10 min until completely dissolved; Hyacolor™-LA, ceramide EOP, and various plant extracts are added at below 40°C and stirred evenly; the mixture is allowed to stand for 30 min to defoam; after cooling to room temperature, the remaining ingredients are added, stirred evenly, and filtered to remove bubbles to obtain a clear orange-yellow essential oil product.

[0024] Example 2 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 35 parts ethylhexyl stearate; 15 parts pentaerythritol tetra(ethylhexanoate); 10 parts diisostearyl malate; 10 parts caprylic / capric triglyceride; 5 parts isononyl isononanoate; 0.3 parts lecithin; 0.3 parts ubiquinone (coenzyme Q10); 0.5 parts ascorbate tetraisopalmitate (VC-IP); 0.3 parts tocopheryl acetate (VE-Ac); 0.3 parts pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid); 0.3 parts Hyacolor™-LA oil-dispersible sodium hyaluronate; 0.1 parts ceramide EOP (oil-dispersible); 0.2 parts Camellia japonica flower extract; 0.05 parts Tubermelanosporum extract; 0.2 parts Carthamus tinctorius flower extract; 0.2 parts Pogostemon cablin. 0.05 parts of cablin leaf extract; 0.3 parts of octyldodecyl alcohol; 0.05 parts of orange peel oil.

[0025] The preparation method of the essential oil is as follows: Ethylhexyl stearate, pentaerythritol tetra(ethylhexanoate), caprylic / capric triglyceride, and isononyl isononanoate are added to a reaction vessel and stirred at 70°C for 15 min until a clear homogeneous solution is formed; diisostearyl malate and lecithin are added at 50°C and stirred for 20 min to form a uniform microlayer dispersion system; the temperature is lowered to below 45°C, and ubiquinone, ascorbate tetraisopalmitate, tocopheryl acetate, and pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester are added sequentially and stirred for 10 min until completely dissolved; Hyacolor™-LA, ceramide EOP, and various plant extracts are added at below 40°C and stirred evenly; the mixture is allowed to stand for 30 min to defoam; after cooling to room temperature, the remaining ingredients are added, stirred evenly, and filtered to remove bubbles to obtain a clear orange-yellow essential oil product.

[0026] Example 3 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 45 parts ethylhexyl stearate; 8 parts pentaerythritol tetra(ethylhexanoate); 6 parts diisostearyl malate; 10 parts caprylic / capric triglyceride; 5 parts isononyl isononanoate; 0.8 parts lecithin; 0.5 parts ubiquinone (coenzyme Q10); 1 part ascorbate tetraisopalmitate (VC-IP); 0.5 parts tocopheryl acetate (VE-Ac); 0.2 parts pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid); 0.8 parts Hyacolor™-LA oil-dispersible sodium hyaluronate; 0.3 parts ceramide EOP (oil-dispersible); 0.5 parts Camellia japonica flower extract; 0.2 parts Tubermelanosporum extract; 0.5 parts Carthamus tinctorius flower extract; 0.5 parts Pogostemon cablin. 0.2 parts of cablin leaf extract; 0.5 parts of octyldodecyl alcohol; 0.1 parts of orange peel oil.

[0027] The preparation method of the essential oil is as follows: Ethylhexyl stearate, pentaerythritol tetra(ethylhexanoate), caprylic / capric triglyceride, and isononyl isononanoate are added to a reaction vessel and stirred at 70°C for 15 min until a clear homogeneous solution is formed; diisostearyl malate and lecithin are added at 50°C and stirred for 20 min to form a uniform microlayer dispersion system; the temperature is lowered to below 45°C, and ubiquinone, ascorbate tetraisopalmitate, tocopheryl acetate, and pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid) ester are added sequentially and stirred for 10 min until completely dissolved; Hyacolor™-LA, ceramide EOP, and various plant extracts are added at below 40°C and stirred evenly; the mixture is allowed to stand for 30 min to defoam; after cooling to room temperature, the remaining ingredients are added, stirred evenly, and filtered to remove bubbles to obtain a clear orange-yellow essential oil product.

[0028] Comparative Example 1 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 60 parts of ethylhexyl stearate; 15 parts of caprylic / capric triglyceride; 5 parts of isononyl isononanoate; 0.5 parts of ubiquinone (coenzyme Q10); 1 part of tetraisopalmitate ascorbate (VC-IP); 0.5 parts of tocopheryl acetate (VE-Ac).

[0029] Comparative Example 2 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 50 parts of ethylhexyl stearate; 20 parts of pentaerythritol tetra(ethylhexanoate); 10 parts of diisostearyl malate; 5 parts of caprylic / capric triglyceride; 5 parts of isononyl isononanoate; 0.5 parts of ubiquinone (coenzyme Q10); 0.5 parts of tocopherol acetate (VE-Ac).

[0030] Comparative Example 3 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 40 parts of ethylhexyl stearate; 20 parts of caprylic / capric triglyceride; 5 parts of isononyl isononanoate; 1 part of tetraisopalmitate ascorbate (VC-IP); 0.5 parts of tocopheryl acetate (VE-Ac); 0.1 parts of orange peel oil.

[0031] Comparative Example 4 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 40 parts ethylhexyl stearate; 10 parts pentaerythritol tetra(ethylhexanoate); 8 parts diisostearyl malate; 8 parts caprylic / capric triglyceride; 0.5 parts lecithin; 0.5 parts ubiquinone (coenzyme Q10); 0.2 parts pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid); 0.5 parts Hyacolor™-LA oil-dispersible sodium hyaluronate; 0.2 parts ceramide EOP (oil-dispersible); 0.3 parts Camellia japonica flower extract; 0.1 parts Tubermelanosporum extract; 0.3 parts Carthamus tinctorius flower extract; 0.1 parts Pogostemon cablin leaf extract; 0.5 parts octyldodecyl alcohol.

[0032] Comparative Example 5 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 40 parts of ethylhexyl stearate; 10 parts of pentaerythritol tetra(ethylhexanoate); 8 parts of diisostearyl malate; 8 parts of caprylic / capric triglyceride; 5 parts of isononyl isononanoate; 0.5 parts of lecithin; 1 part of ascorbic acid tetraisopalmitate (VC-IP); 0.2 parts of pentaerythritol tetra(bis-tert-butylhydroxyhydrocinnamic acid); 0.5 parts of Hyacolor™-LA oil-dispersible sodium hyaluronate; 0.2 parts of ceramide EOP (oil-dispersible).

[0033] Comparative Example 6 The difference from Example 1 is that this example provides an essential oil, the raw materials for which are prepared include: 40 parts of ethylhexyl stearate; 10 parts of pentaerythritol tetra(ethylhexanoate); 8 parts of diisostearyl malate; 8 parts of caprylic / capric triglyceride; 5 parts of isononyl isononanoate.

[0034] Table 1 Formulations of Examples and Comparative Examples

[0035] test: 1. Visual inspection Objective: To evaluate the clarity, transparency, and presence of layering or sedimentation in essential oils.

[0036] Procedure: Let the essential oil stand at room temperature (25℃) for 24 hours. Take about 5mL of sample and place it in a transparent glass colorimetric tube.

[0037] Visually inspect the sample: record whether it is clear and transparent, slightly turbid, layered, or has particles precipitated.

[0038] Record the sample color (light yellow, golden yellow, etc.) at the same time.

[0039] Judgment criteria: Clear, golden, and transparent: Excellent Slightly yellow and transparent or slightly cloudy: Good Obvious layering or sedimentation: unacceptable 2. Light transmittance (550nm) A UV-Vis spectrophotometer (ShimadzuUV-2600) was used. The oil sample was diluted in a cuvette with a 1 cm optical path. After calibrating the blank solvent, the transmittance was measured at a wavelength of 550 nm. Each sample was measured three times, and the average value was taken.

[0040] Judgment criteria: Light transmittance ≥95% is excellent, 90–95% is good, and <90% is unqualified.

[0041] 3. Viscosity Measurement Instrument: NDJ-5 rotational viscometer. Place the oil sample in a water bath at room temperature (25℃) for equilibration for 10 minutes. Select a measurement speed of 60 rpm and rotate the sample to measure its viscosity. Measure each sample three times and take the average value.

[0042] Judgment criteria: 400~500mPa·s: Suitable for the feel of facial oils 600 mPa·s: Thick, difficult to spread <350 mPa·s: Too thin; oil phase may be unstable. 4. Refractive index measurement Using an Abbe refractometer, the temperature was controlled at 25℃. A small amount of oil sample was added to the instrument platform. The instrument was adjusted, and the refractive index was read. Each sample was measured three times, and the average value was taken.

[0043] 5. Antioxidant activity retention rate (DPPH method) Objective: To evaluate the antioxidant capacity of essential oils and their activity retention rate after storage.

[0044] step: Prepare a DPPH ethanol solution (0.1 mM).

[0045] The essential oil sample was diluted in ethanol (oil:solvent = 1:10 w / v).

[0046] Mix 1 mL of oil solution with 1 mL of DPPH solution and react in the dark for 30 minutes.

[0047] The absorbance (A) was measured at 517 nm using a UV-Vis photometer.

[0048] Calculate the antioxidant retention rate relative to the initial value (t=0): Retention rate %) = A after storage / A initial * 100%.

[0049] 6. Q10 and VC-IP retention rate (HPLC) Dissolve 0.1 g of the essential oil in 5 mL of ethanol and sonicate for 5 minutes until completely dissolved. Filter through a 0.45 μm filter membrane and inject into the HPLC system. Conditions: C18 column, acetonitrile / water gradient elution mobile phase, detection wavelength Q10 = 275 nm, VC-IP = 245 nm, flow rate 1.0 mL / min. Calculate the retention rate by comparing the peak area with the initial sample peak area.

[0050] 7. Accelerate storage stability Procedure: Place the oil sample in a constant temperature oven at 40℃±2℃ and store it in the dark for 90 days. Observe the appearance of the oil sample every 15 days and record any changes in layering, oil separation, turbidity, or color. Determine the stability by comparing the oil sample with its initial appearance.

[0051] 8. Changes in skin moisture content The subjects' hands were clean and dry, and baseline moisture levels (Corneometer MPA5) were measured. 0.02 mL / cm² of solution was applied. 2 Apply the facial oil and gently massage it in evenly. After 30 minutes, measure the skin hydration level in the same area again.

[0052] Δ% = (Moisture content after use - Moisture content before use) / Moisture content after use. Measure 3 times for each person and take the average value.

[0053] 9. Subjective evaluation of skin feel Evaluate the oil's spreadability, absorbency, and comfort.

[0054] Procedure: Twenty volunteers were selected for blind testing of different oil formulations. Subjects applied 0.02 mL / cm² oil to the back of their hands.2 Apply the oil sample and gently massage for 30 seconds. Rate the absorption, lubrication, and refreshing sensation (1-5 points, 5 points being the best). The average score will be used as the subjective evaluation result.

[0055] 10. Stability of freezing / heating cycles Freeze the oil sample at -5℃ for 2 hours. Remove and place in a constant temperature environment at 25℃ for 2 hours. Complete one cycle, for a total of 5 cycles. After each cycle, observe the oil sample to see if it separates into layers, becomes cloudy, or separates into oil.

[0056] 2 Test Results

[0057] Test results show that the essential oil of the present invention, through the construction of a micro-layer oil-phase stable system, exhibits excellent transparency, viscosity stability, antioxidant activity retention rate, active ingredient stability, skin moisturizing effect, and freeze / heat cycle stability in Examples 1-3, with Example 1 being the best example. In contrast, Comparative Examples 1-6, due to the lack of interface structure optimization or key active ingredients, showed layering, oil separation, turbidity, or active ingredient degradation, resulting in a significant decrease in skin hydration improvement and subjective user experience. This indicates that the micro-layer oil-phase stable system and component synergy play a decisive role in the overall performance and stability of the essential oil, while also verifying the necessity and creativity of the component and formulation design.

[0058] Figure 1 The facial images (Antera 3D camera) taken after the experimenter used the essence oil of Example 1 for 7 days show that the redness value decreased from 21.6 to 16.61.

Claims

1. An essential oil characterized in that, The raw materials for preparing the same comprise base oil, functional oil, antioxidant, moisturizer, plant extract, and auxiliary agent.

2. The serum oil of claim 1, wherein, The base oil is ethylhexyl stearate.

3. The serum oil of claim 1, wherein, The functional oil is diisostearyl malate, caprylic / capric triglyceride, isononyl isononanoate, and lecithin.

4. The serum oil of claim 1, wherein, The antioxidant is coenzyme Q10, ascorbyl tetraisopalmitate, tocopheryl acetate, and pentaerythrityl tetra (di-tert-butylhydroxyhydrocinnamate).

5. The serum oil of claim 1, wherein, The moisturizer is Hyacolor™-LA oil-dispersible sodium hyaluronate and ceramide EOP.

6. The serum oil of claim 1, wherein, The plant extract is Camellia japonica flower extract, Tuber melanosporum extract, Carthamus tinctorius flower extract, and Pogostemon cablin leaf extract.

7. The serum oil of claim 1, wherein, The auxiliary agent is pentaerythrityl tetra (ethylhexanoate), octyldodecanol, and orange peel oil.

8. The serum oil of claim 3, wherein, The mass ratio of diisostearyl malate, caprylic / capric triglyceride, isononyl isononanoate, and lecithin is 8:8:5:0.

5.

9. The serum oil of claim 6, characterized by, The mass ratio of Camellia japonica flower extract, Tuber melanosporum extract, Carthamus tinctorius flower extract, and Pogostemon cablin leaf extract is 3:1:3:

1.

10. A method of preparing the essential oil according to any one of claims 1 to 9, characterized in that, The steps are as follows: ethylhexyl stearate, pentaerythrityl tetra (ethylhexanoate), caprylic / capric triglyceride, and isononyl isononanoate are added to a reaction kettle, stirred at 70°C for 15 min, until a clear homogeneous solution is formed; Diisostearyl malate and lecithin are added at 50°C, and stirring is maintained for 20 min to form a uniform micro-layer dispersion system; The temperature is lowered to below 45°C, and ubiquinone, ascorbyl tetraisopalmitate, tocopheryl acetate, and pentaerythrityl tetra (di-tert-butylhydroxyhydrocinnamate) are added in sequence, and stirred for 10 min until completely dissolved; Hyacolor™-LA, ceramide EOP, and each plant extract are added at below 40°C, and stirred until uniform; stand for 30 min to remove bubbles; After being cooled to room temperature, orange peel oil and Pogostemon cablin leaf extract are added, stirred until uniform, and filtered to remove bubbles, to obtain a clear orange-yellow essence oil product.

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