Eyebrow pencil

Abstract

The invention discloses an eyebrow pencil, and belongs to the field of cosmetics. The eyebrow pencil aims at solving the problem that an existing eyebrow pencil cannot give consideration to long-acting makeup keeping, smooth smearing and low irritation. The eyebrow pencil refill composition comprises a composite film forming system, a solvent and a solvent, wherein the composite film forming system is composed of polyesteride-5, trimethylsiloxy silicate and trimethyl pentaphenyl trisiloxane according to a specific weight ratio; the compound wax-based framework system is composed of ozokerite, oxidized polyethlene wax and Japanese wax; the specific skin feeling conditioning agent is a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer; the plant-derived bioactive compound is prepared from herba centellae, herba portulacae and zanthoxylum piperitum fruit extracts; a colorant and a volatile solvent are also included. Through the synergistic effect of all the components, the eyebrow pencil has excellent water-proof, oil-proof, migration-resistant and makeup-keeping performance, excellent smearing smoothness, good mechanical strength and low irritation, is suitable for sensitive skin, is simple in preparation method and is suitable for industrial production.

Description

Technical Field

[0001] This invention relates to the field of cosmetic technology, and in particular to an eyebrow pencil, specifically to an eyebrow pencil composition having excellent staying power, smooth application, and low irritation, as well as its preparation method and uses. Background Technology

[0002] Eyebrow pencils are core makeup products used to shape eyebrows, fill in gaps, and enhance the three-dimensionality of facial makeup. With consumers increasingly focused on the refinement of their makeup and skin health, modern eyebrow pencils not only need to provide good color payoff and staying power, but also must have an excellent feel (smooth, non-clumping) and low irritation to the skin (especially the sensitive skin around the eyes).

[0003] Currently, eyebrow pencils on the market are mainly divided into oil-soluble and water-soluble systems. Existing technology, such as CN110314123A, discloses an eyebrow pencil containing extracts from various plants such as ginger and ginseng, aiming to promote eyebrow growth by nourishing hair follicles. However, while such eyebrow pencils contain a large amount of natural oils and plant extracts, making them relatively safe, they often result in a soft, easily broken lead with poor sebum and sweat resistance. Consumers with oily skin are prone to smudging and short-lasting makeup, requiring frequent touch-ups, especially in summer.

[0004] On the other hand, in pursuit of long-lasting makeup effects, existing technologies such as CN112957303B disclose a waterproof and sweat-proof eyebrow pencil containing multiple plant extracts, which improves structural strength by adding Japanese wax and polyethylene glycol wax. However, to achieve a strong waterproof and sweat-proof effect, such formulas usually rely on high-melting-point waxes and a large amount of film-forming agents. This leads to increased resistance during application, resulting in "powder caking" or "skin pulling" phenomena. Not only is the user experience poor, but long-term use may also cause damage to the skin around the eyes due to physical friction.

[0005] In addition, existing technologies such as CN111297734A disclose the use of emollients such as squalane and babassu seed oil to improve skin affinity. However, such oily ingredients are easy to migrate on the skin surface. Although they are smooth when applied initially, the oil spreads over time, which can cause the lines to become blurred and make it difficult to maintain fine eyebrow lines.

[0006] Further analysis of existing technologies reveals that the "makeup retention-skin feel-safety" triangle faced by eyebrow pencil products stems primarily from the following technical reasons: Achieving makeup retention relies on high-hardness film-forming resins and high-melting-point wax-based systems, which inevitably increases application resistance. Furthermore, the film-forming agents and waxes themselves possess certain physical and chemical irritants to the sensitive skin around the eyes. Conversely, achieving smooth application and a gentle skin feel requires the addition of large amounts of low-melting-point waxes, oils, and gentle emollients. However, these ingredients are easily emulsified and migrated by sebum and sweat, leading to a rapid deterioration in makeup retention. While existing technologies have attempted various compromises, they have consistently failed to fundamentally overcome this technical bottleneck.

[0007] Therefore, there is a common technical contradiction in the existing technology: in order to achieve long-lasting makeup (waterproof, sweatproof, and sebum-resistant), it is necessary to increase the hardness and hydrophobicity of the system, but this often sacrifices the smoothness and feel of the application and increases the burden on the skin; conversely, in order to pursue gentleness and smoothness, a large amount of moisturizing oil and low melting point wax are used, which will lead to poor makeup-holding effect.

[0008] In view of the shortcomings of the existing technology, there is an urgent need to develop a new eyebrow pencil composition that can achieve both "long-lasting makeup" and "smooth application" while also being low in irritation. Summary of the Invention

[0009] In view of the shortcomings of the existing technology, the purpose of this invention is to provide an eyebrow pencil that solves the technical problem that existing eyebrow pencil compositions are difficult to achieve in a way that simultaneously provides excellent makeup-holding performance (waterproof, sweatproof, and anti-migration), smooth application, and low skin irritation. The invention provides an eyebrow pencil composition with synergistic effects and its preparation method.

[0010] After in-depth research into the underlying mechanisms of the technical contradictions in eyebrow pencil products, this invention recognizes that to solve the above problems simultaneously, it is not possible to simply add functional ingredients. Instead, a systematic and synergistic design is needed from four levels: "film-forming structure design", "wax-based crystal network optimization", "skin feel regulation mechanism establishment" and "skin microecology maintenance". This will enable positive interactions between the components, resulting in a synergistic effect where the whole is greater than the sum of its parts.

[0011] The above-mentioned objective of this invention is achieved through the following technical solutions: On one hand, the present invention discloses an eyebrow pencil, wherein the pencil lead composition comprises the following components by weight percentage: A composite film-forming system, wherein the composite film-forming system is composed of polyester-5, trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane, and the weight ratio of polyester-5, trimethylsiloxysilicate to trimethylpentaphenyltrisiloxane is (2-4):(1-3):(1-2); Based on the total weight of the composition, 10% to 25% is a compound wax-based framework system, which is composed of ceresin wax, oxidized polyethylene wax and Japanese wax; Based on the total weight of the composition, 1% to 5% of a skin feel modifier, wherein the skin feel modifier is a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer; Based on the total weight of the composition, 0.5% to 3% of a plant-derived bioactive complex, said plant-derived bioactive complex being a mixture of Centella asiatica extract, Portulaca oleracea extract and Zanthoxylum piperitum fruit extract; 15% to 30% colorant; The remainder is volatile solvent.

[0012] As a further technical solution of the present invention: in the compound wax-based skeleton system, the weight ratio of cerescarpium, oxidized polyethylene wax and Japanese wax is (3-5):(2-4):(1-3).

[0013] As a further technical solution of the present invention: in the plant-derived bioactive complex, the weight ratio of Centella asiatica extract, Portulaca oleracea extract and Zanthoxylum bungeanum fruit extract is (1-2):(1-2):(1-3).

[0014] As a further technical solution of the present invention: the volatile solvent is one or more of isododecane, isohexadecane, or C13-16 isoalkanes. Isododecane is the most preferred volatile solvent, with moderate volatility, capable of rapidly evaporating after use to form a dry film, while also possessing good solubility and compatibility with organosilicon film-forming agents. Isohexadecane and C13-16 isoalkanes are optional alternative solvents, which can also achieve the technical effects of the present invention, but are slightly inferior to isododecane in terms of drying speed.

[0015] As a further technical solution of the present invention: the pencil lead composition further comprises 0.1% to 2% of an antioxidant, wherein the antioxidant is selected from one or more of tocopherol (vitamin E), butylated hydroxytoluene (BHT), or tetrapentaerythritol ester (butylated hydroxyhydrocinnamic acid). The addition of antioxidants can effectively prevent oxidative rancidity of unsaturated components in the formula and extend the shelf life of the product. Tocopherol (vitamin E) is the most preferred antioxidant of the present invention due to its natural source and excellent safety.

[0016] As a further technical solution of the present invention: the pencil lead composition further comprises 0.1% to 1% of a suspending agent, wherein the suspending agent is distearate dimethylammonium lithium montmorillonite or silachlor hydrate. The function of the suspending agent is to prevent the powder components such as colorants and skin feel modifiers from settling in the system, ensuring the uniformity and stability of the product during storage. Distearate dimethylammonium lithium montmorillonite is an organically modified montmorillonite that can form a thixotropic gel network in oily systems, exhibiting good suspension stability.

[0017] As a further technical solution of the present invention: the colorant is selected from CI 77499 (black iron oxide), CI 77492 (yellow iron oxide), CI 77491 (red iron oxide), and mixtures thereof. By adjusting the proportions of the above three iron oxide colorants, various eyebrow pencil colors ranging from light brown to dark black can be obtained to meet the needs of consumers with different hair colors and skin tones. In the formulation system of the present invention, the total amount of colorant is 15% to 30%, preferably 18% to 25%, and more preferably 20% to 22%.

[0018] On the other hand, the present invention discloses a method for preparing an eyebrow pencil as described above, comprising the following steps: Step S1: Mix the compound wax-based skeleton system, volatile solvent and skin feel modifier, heat to 85℃-95℃, stir until completely melted and mixed evenly to obtain an oil phase mixture; Step S2: Add trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane from the composite film-forming system to the oil phase mixture obtained in step S1, stir evenly, cool to 75℃-85℃, add colorant and plant-derived bioactive complex, and grind and disperse to a fineness ≤20μm; Step S3: Cool down to 60℃-70℃, add polyester-5 and optional antioxidants and suspending agents, and stir evenly; Step S4: Pour the mixture obtained in step S3 into a mold, cool and solidify, demold, and obtain the eyebrow pencil lead; Step S5: Install the lead into the eyebrow pencil tube.

[0019] In the above preparation method, temperature control at each step is crucial to the quality of the final product. Heating to 85℃-95℃ in step S1 ensures that the ceresin wax (melting point approximately 70℃-85℃), oxidized polyethylene wax (melting point approximately 80℃-95℃), and Japanese wax (melting point approximately 45℃-55℃) are completely melted and thoroughly mixed. Cooling to 75℃-85℃ in step S2 before adding the colorant and plant complex is to avoid damage to the hue of the colorant and the heat-sensitive active ingredients in the plant extracts due to high temperatures. Cooling to 60℃-70℃ in step S3 before adding polyester-5 is because polyester-5 may undergo thermal degradation above this temperature, and within this temperature range, polyester-5 can be thoroughly mixed with other components without affecting its film-forming properties.

[0020] As a further technical solution of the present invention: the grinding and dispersion in step S2 is carried out using a three-roll mill, with 2-4 grinding cycles. The three-roll mill utilizes the shear force between the three rollers to break up the agglomerated particles in the slurry, allowing the colorant to be uniformly dispersed in the system. When the grinding cycle is less than 2 times, it is difficult to achieve the fineness requirement of ≤20μm; when the grinding cycle is more than 4 times, production efficiency decreases and equipment wear is aggravated. The most preferred grinding cycle is 3 times, which can ensure both dispersion fineness and production efficiency.

[0021] Furthermore, this invention discloses the application of the aforementioned eyebrow pencil in the preparation of cosmetics that promote eyebrow follicle health and reduce irritation. The eyebrow pencil of this invention not only possesses excellent makeup performance, but its unique plant-derived bioactive complex also gently promotes microcirculation in the eyebrow area, improving blood and nutrient supply to the hair follicles. Long-term use helps maintain healthy eyebrows. This dual function of "makeup + skincare" gives it a unique technological advantage and market value among eyebrow pencil products.

[0022] In summary, compared with the prior art, the present invention includes at least one of the following beneficial technical effects: Exceptional staying power: Through the combination of a composite film-forming system and a compound wax-based framework, the resulting eyebrow makeup film has extremely strong anti-sebum and anti-sweat capabilities. Tests show that, under conditions of 35℃±2℃ and 60%±5% humidity, after continuous wear for 8 hours, the smudged area does not exceed 10% of the initial area, the lines remain clear, and there is no significant color fading or diffusion.

[0023] Excellent application smoothness: The skin feel modifier (silicone elastomer) and the Japanese wax in the compound wax base work together to reduce the sliding friction during application to an extremely low level. In sensory evaluation tests, more than 95% of the subjects reported that "it can be applied in one stroke without any sticking or gliding, like silk gliding across the skin."

[0024] Low irritation and skin-friendly: The addition of specific proportions of Centella Asiatica and Portulaca oleracea extracts effectively neutralizes the potential irritation that makeup products may cause to the skin around the eyes. Skin patch tests conducted after 28 days of continuous use showed zero cases of significant erythema or itching, indicating that this product is suitable for people with sensitive skin.

[0025] Excellent mechanical strength: Through the reasonable combination of ceresin wax and oxidized polyethylene wax, the bending strength (breaking force) of the pencil lead is significantly higher than that of similar long-lasting eyebrow pencils on the market. It is not easy to break during normal use and transportation, thus improving the product's durability.

[0026] Natural finish: The high refractive index of trimethylpentaphenyltrisiloxane gives the eyebrow makeup a natural sheen on the skin, rather than a dull matte or harsh reflection, making it closer to the texture of real eyebrows. Detailed Implementation

[0027] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] This invention provides an eyebrow pencil, wherein the pencil lead composition comprises the following components by weight percentage: (a) A composite film-forming system, wherein the composite film-forming system is composed of polyester-5, trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane, and the weight ratio of polyester-5, trimethylsiloxysilicate to trimethylpentaphenyltrisiloxane is (2-4):(1-3):(1-2); (b) Based on the total weight of the composition, 10% to 25% of a compound wax-based framework system, said compound wax-based framework system being composed of ceresin wax, oxidized polyethylene wax and Japanese wax; (c) Based on the total weight of the composition, 1% to 5% of a skin feel modifier, said skin feel modifier being a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer; (d) Based on the total weight of the composition, 0.5% to 3% of a plant-derived bioactive complex, said plant-derived bioactive complex being a mixture of Centella asiatica extract, Portulaca oleracea extract and Zanthoxylum bungeanum fruit extract; (e) 15% to 30% colorant; (f) The remaining amount of volatile solvent.

[0029] In this invention, the components do not act in isolation, but rather achieve synergistic effects through specific combinations and proportions. This synergistic effect is manifested at multiple levels. The following systematically elaborates on the above-mentioned "four-element synergy" system in conjunction with the technical principles of this invention and the interaction mechanism of each component.

[0030] Composite film-forming system: Traditional film-forming agents (such as single acrylate copolymers) often suffer from either "over-film formation," leading to a tight feeling on the skin, or "insufficient film formation," resulting in poor makeup longevity. This invention employs a combination of three distinctly different film-forming substances: Trimethylsiloxysilicate: This is an organosilicon resin with extremely high film-forming hardness and anti-migration properties, making it a core ingredient for long-lasting makeup. In this invention, its dosage, in ratio to polyester-5 and trimethylpentaphenyltrisiloxane, has been carefully optimized to provide sufficient film-forming strength without being excessively rigid and causing skin discomfort.

[0031] Trimethylpentaphenyltrisiloxane: This is a phenyl silicone oil with a high refractive index. It complements trimethylsiloxysilicate, imparting good gloss and flexibility to the film and preventing cracking caused by hard resins. The high molar refractive index of the phenyl groups in trimethylpentaphenyltrisiloxane allows it to provide both flexibility and a natural gloss, a unique optical property not found in other flexible film-forming components.

[0032] Polyester-5: This is a polyester based on fatty acids and polyols, which acts as a plasticizer in the formulation. When compounded with the aforementioned silicone resins, polyester-5 can adjust the brittleness of the resin film, giving it both strength and elasticity, while also enhancing the dispersibility of pigments. More importantly, the ester groups in the polyester-5 molecule can form hydrogen bonds with the polar components in the wax-based system, thereby enhancing the interfacial compatibility between the film-forming system and the wax-based system, making them form an organic whole.

[0033] Synergistic effect: Trimethylsiloxane provides "skeletal rigidity," trimethylpentaphenyltrisiloxane provides "flexible luster," and polyester-5 provides "dispersion and binding strength." All three are indispensable, together forming a high-performance mesh membrane that is both tough and breathable, while also closely adhering to the skin and hair. A specific weight ratio ensures that the membrane achieves an optimal balance between resisting sebum penetration and adapting to subtle skin movements. When the proportions of the three components are within the range defined by this invention, the glass transition temperature (Tg) and elongation at break of the composite membrane are both in their optimal range, enabling it to resist sebum penetration while maintaining integrity when the skin deforms.

[0034] Compound wax-based framework system: Unlike beeswax and carnauba wax commonly used in the prior art, this invention uses a combination of oxkerite, oxidized polyethylene wax and Japanese wax.

[0035] Cereal wax: It has a high melting point (typically between 70℃ and 85℃) and dense crystals, which can give the pen refill excellent structural strength and shaping ability, preventing it from softening at high temperatures. In this invention, cereal wax is used as a "skeleton wax" to provide basic mechanical strength for the pen refill.

[0036] Oxidized polyethylene wax: It has excellent pigment dispersibility and good adhesion to the skin, while its oxidative polarity helps it to be compatible with other components (especially polyester-5). The polar functional groups of oxidized polyethylene wax enable it to form a strong adsorption effect with the surface of the colorant, thereby improving the dispersion uniformity and stability of the colorant in the system.

[0037] Japanese wax: A plant-based fatty wax, mainly composed of glyceryl palmitate, possesses unique flexibility that significantly reduces friction during application, providing a smooth feel. With a melting point between 45℃ and 55℃, Japanese wax has the lowest melting point of the three types of wax. It solidifies last during crystallization, filling the skeletal network formed by ceresin and oxidized polyethylene wax, acting as a "lubricant."

[0038] Synergistic Effect: Cedar wax provides firmness, oxidized polyethylene wax enhances cohesion and adhesion, and Japanese wax provides extensibility and smoothness. These three components form a stable crystalline network, ensuring the mechanical strength (resistance to breakage) of the pen refill during production, filling, and use, while also giving the product a velvety, silky smooth application feel. Through differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis, the inventors discovered that when the three waxes crystallized in a specific ratio, their crystallization peaks underwent a significant red shift and broadening, indicating that they formed a eutectic structure rather than a simple physical mixture. This is the microstructural basis for the synergistic effect.

[0039] Skin feel modifier: This invention specifically selects a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer. This is an organosilicon elastomer powder. Its spherical particles can act as a "micro-roll-bead" physical barrier between the skin and the pigment / wax, greatly reducing the sliding resistance during application. At the same time, its porous structure can also absorb excess sebum secreted by the skin, helping to enhance the makeup's staying power. Through comparative experiments, the inventors found that the spherical particle morphology and particle size distribution (D50 approximately 3-10 μm) of this specific skin feel modifier allow it to be evenly distributed between the pen tip surface and the skin during application, achieving a unique mechanism of "rolling friction replacing sliding friction," which cannot be achieved by sheet-like or fibrous skin feel modifiers.

[0040] Plant-derived bioactive complex: In response to the potential irritation issues that may arise from traditional long-lasting makeup products, this invention creatively incorporates a specific combination of plant extracts.

[0041] Centella asiatica extract: possesses excellent soothing, repairing, and anti-inflammatory properties, effectively combating skin discomfort that may be caused by film-forming agents or prolonged makeup wear. Its main active ingredient, asiaticoside, can significantly inhibit the activation of the nuclear factor κB (NF-κB) signaling pathway, thereby reducing the production of inflammatory cytokines.

[0042] Purslane extract: Rich in flavonoids, it has antioxidant and anti-allergic effects and can reduce periorbital sensitivity. The flavonoids in purslane (especially quercetin and kaempferol) can inhibit mast cell degranulation and histamine release, thereby blocking the allergic reaction upstream.

[0043] Litsea cubeba fruit extract: Contains ingredients that promote local microcirculation, gently stimulating hair follicles, and long-term use helps maintain eyebrow vitality. The sanshool components in Litsea cubeba fruit extract can activate the transient receptor potential vanillic acid subtype 1 (TRPV1) channel, producing a mild warming sensation and vasodilatory effect, promoting increased local blood flow. This mechanism of action is uniquely innovative in eyebrow pencil products because traditional eyebrow pencils only focus on makeup functions, while the Litsea cubeba fruit extract of this invention adds a skincare function.

[0044] Synergistic Effect: In long-lasting makeup formulations, Centella asiatica and Portulaca oleracea act to "defend" against potential negative irritants from cosmetics, while Zanthoxylum bungeanum fruit extract actively promotes hair follicle health. This "one for protection, one for defense" plant combination cleverly addresses the safety concerns of long-lasting makeup products. The inventors demonstrated through in vitro cell models that the combination of the three extracts showed significantly better protective effects on human keratinocytes and increased proliferation of human dermal fibroblasts compared to individual extracts or combinations of any two, demonstrating a clear synergistic effect.

[0045] In this invention, the core of the above technical solution lies in achieving a leap in overall performance through the "synergy of four elements." The following sections will elaborate on each technical element and its synergistic effect.

[0046] The composite film-forming system used in this invention is composed of polyester-5, trimethylsiloxysilicate, and trimethylpentaphenyltrisiloxane in a specific weight ratio of (2-4):(1-3):(1-2). This combination is not a simple functional additive, but rather achieves an unexpected synergistic effect through the interaction of the three components at the molecular level.

[0047] Specifically, trimethylsiloxane is an organosilicon resin with a three-dimensional network molecular structure, exhibiting extremely high film-forming hardness and excellent anti-migration properties. It is a core ingredient that gives eyebrow makeup its long-lasting wear. However, using trimethylsiloxane alone can lead to an overly hard and brittle film, which is prone to cracking when the skin undergoes micro-expression changes, affecting the integrity and adherence of the makeup. Trimethylpentaphenyltrisiloxane, a phenyl silicone oil, possesses high refractive index optical properties and good flexibility due to its phenyl groups. It complements trimethylsiloxane, giving the film a moderate degree of flexibility and a natural gloss, avoiding the dry cracking and stiff reflection problems that easily occur with hard resin films. Polyester-5 is a polyester component based on fatty acids and polyols. In the composite film-forming system of this invention, it plays a key role as a "molecular bridge"—the polyester-5 molecule contains both polar ester groups and non-polar long-chain alkyl groups, which can form good interfacial compatibility with the siloxane skeleton in trimethylsiloxysilicate and the phenyl group in trimethylpentaphenyltrisiloxane, respectively, thereby enhancing the intermolecular forces among the three and forming a rigid-flexible, dense three-dimensional network film-forming network.

[0048] Through systematic comparative experiments, the inventors discovered that when the weight ratio of polyester-5, trimethylsiloxysilicate, and trimethylpentaphenyltrisiloxane is within the range of (2-4):(1-3):(1-2), the composite film formed by these three components exhibits optimal mechanical and optical properties. Outside this range—for example, when the proportion of polyester-5 is too high, the composite film's resistance to sebum penetration significantly decreases; when the proportion of trimethylsiloxysilicate is too high, the film becomes too brittle, leading to microcracks in areas of skin with subtle facial expressions, thus reducing makeup longevity; and when the proportion of trimethylpentaphenyltrisiloxane is too high, the film's hydrophobicity and anti-migration properties are insufficient. Only within the specific ratio range defined by this invention can the three components produce a synergistic rather than antagonistic effect.

[0049] To verify the aforementioned synergistic effect, the inventors conducted the following comparative experiments: A control formulation containing only trimethylsiloxysilicate, a combination formulation of trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane (ratio 2:1), a combination formulation of trimethylsiloxysilicate and polyester-5 (ratio 2:1), and the ternary composite film-forming system formulation of Example 1 of this invention (ratio 4:2:1) were prepared. Under the same test conditions (artificial sebum added and left to stand for 10 minutes, then wiped with filter paper), the control formulation containing only trimethylsiloxysilicate received an oil resistance rating of C (significant smudging), the combination formulations received an oil resistance rating of B (slight smudging), while the ternary composite film-forming system of Example 1 of this invention received an oil resistance rating of A (no color transfer). The above results clearly show that the addition of polyester-5 is not a simple incremental effect, but rather, through the synergistic effect between it, trimethylsiloxysilicate, and trimethylpentaphenyltrisiloxane, the overall anti-sebum performance of the composite film system significantly surpasses the simple sum of any two combinations, producing an unexpected technical effect of "1+1+1>3".

[0050] Furthermore, the composite film-forming system of this invention also exhibits a significant synergistic effect in terms of anti-migration durability. In an 8-hour makeup-wearing test on humans, the control formulation containing only trimethylsiloxysilicate scored 4.2 points at 4 hours and 3.1 points at 8 hours, while the combination formulation (trimethylsiloxysilicate + trimethylpentaphenyltrisiloxane) scored 4.5 points at 4 hours and 3.8 points at 8 hours. In contrast, Example 1 of this invention achieved a score as high as 4.5 points at 8 hours, demonstrating significantly better durability than the control and the combination formulations. This result proves that the addition of polyester-5 significantly improves the structural integrity and fatigue resistance of the composite film layer during prolonged wear, enabling the film layer to better adapt to the dynamic deformation of the skin without damage.

[0051] Based on the above findings, the present invention further optimizes the weight ratio range of the composite film-forming system: the weight ratio of polyester-5, trimethylsiloxysilicate, and trimethylpentaphenyltrisiloxane is (2-4):(1-3):(1-2). Preferably, the weight ratio is (3-4):(2-3):(1-2). More preferably, the weight ratio is 4:2:1 or 3:2:1.

[0052] The compound wax-based framework system used in this invention consists of oxokerite, oxidized polyethylene wax, and Japan wax in a specific weight ratio of (3-5):(2-4):(1-3). This wax-based combination is fundamentally different from the single or simple mixture of wax-based systems such as beeswax, carnauba wax, and microcrystalline wax commonly used in traditional eyebrow pencils. Its innovation lies in the fact that by compounding three wax components with different melting points, crystallization habits, and rheological properties, a three-dimensional network framework with a gradient crystal structure of "rigid-tough-smooth" is formed.

[0053] A deeper analysis from a technical mechanism perspective: Ceramide wax is a natural mineral wax with an extremely high melting point and excellent crystallinity. It can form a high-strength skeletal structure within the pencil lead, giving it excellent mechanical strength and high-temperature stability, preventing softening, deformation, or breakage during production and storage. However, the crystalline network of ceramide wax is too rigid, leading to brittleness and high application resistance when used alone. Oxidized polyethylene wax is a synthetic wax modified by oxidation. Its molecules incorporate polar oxygen-containing functional groups, giving it excellent pigment dispersion ability and good adhesion to the skin. Simultaneously, oxidized polyethylene wax is more flexible than ceramide wax, forming a complementary crystalline network that enhances the pencil lead's cohesion and impact resistance. Japanese wax is a plant-based fatty wax. Its unique chemical composition (mainly glyceryl palmitate) gives it excellent extensibility and a low coefficient of friction, significantly reducing the sliding resistance of the pencil lead when applied to the skin, making the eyebrow drawing process silky smooth.

[0054] The inventors discovered that when the weight ratio of geomesh wax, oxidized polyethylene wax, and Japanese wax is within the range of (3-5):(2-4):(1-3), the three components can form a unique "interpenetrating network structure" during the crystallization process: the high-melting-point geomesh wax crystallizes first to form the primary skeleton, the medium-melting-point oxidized polyethylene wax crystallizes in the gaps of the geomesh wax skeleton and interlocks with it, and the low-melting-point Japanese wax fills the outermost layer of the network, playing a role in lubrication and plasticization. This gradient crystallization network enables the pen refill to simultaneously possess the "impossible triangle" properties of high strength, high toughness, and low coefficient of friction.

[0055] To verify the aforementioned synergistic effect, the inventors conducted a systematic formulation comparison experiment. While maintaining the same components as in Example 1, the inventors prepared a control formulation containing only ceresin, a combination formulation of ceresin and oxidized polyethylene wax (ratio 3:2), a combination formulation of ceresin and Japanese wax (ratio 3:1), a combination formulation of oxidized polyethylene wax and Japanese wax (ratio 2:1), and the ternary compound wax-based formulation of Example 1 of this invention (ratio 3:2:1). Through three-point bending strength testing and sensory evaluation of application smoothness (scoring from 1 to 5 points, with 5 being the best), the breaking force of the control formulation was 2.6 N and the smoothness score was 2.1; the breaking force of the combination of cerescarpone and oxidized polyethylene wax was 3.5 N and the smoothness score was 3.2; the breaking force of the combination of cerescarpone and Japanese wax was 3.0 N and the smoothness score was 4.1; the breaking force of the combination of oxidized polyethylene wax and Japanese wax was 2.9 N and the smoothness score was 4.3; while the ternary compound wax system of Example 1 of this invention had a breaking force of 3.8 N and a smoothness score of 4.7. These results indicate that the overall performance of the ternary compound system of this invention is significantly better than the simple sum of any two combinations, fully demonstrating the synergistic effect among cerescarpone, oxidized polyethylene wax, and Japanese wax.

[0056] Based on the above findings, the present invention further optimizes the weight ratio of each component in the compound wax-based framework system: the weight ratio of ceresin wax, oxidized polyethylene wax, and Japanese wax is (3-5):(2-4):(1-3). More preferably, the weight ratio is (3-4):(2-3):(1-2). Most preferably, the weight ratio is 3:2:1 or 4:2:1. The total amount of the compound wax-based framework system is 10% to 25% of the total weight of the eyebrow pencil lead composition, preferably 12% to 20%, more preferably 14% to 18%. When the total wax content is less than 10%, the mechanical strength of the lead is insufficient, and it is easy to break during use and transportation; when the total wax content is greater than 25%, the smoothness of the lead application and the dispersion of the pigment will be adversely affected, and it may increase the occlusive feeling and greasiness of the skin.

[0057] The skin feel modifier used in this invention is a vinyl dimethicone / methicone silsesquioxane crosspolymer. This is an organosilicon elastomer powder with a microstructure consisting of spherical particles of organosilicon resin coated with organosilicon rubber, possessing a unique core-shell bilayer structure. The inventors have discovered that this skin feel modifier plays a dual role in the formulation of this invention, acting as both a "physical micro-roller" and a "chemical oil-controlling agent," a function that cannot be replaced by any other skin feel modifier.

[0058] From a physical mechanism perspective: the spherical particles of this cross-linked polymer powder typically range in size from 2 to 15 μm. During application, these tiny spherical particles act as a ball bearing-like physical barrier between the pigment particles, wax crystals, and the skin surface, transforming sliding friction into rolling friction, thereby significantly reducing sliding resistance during application. This unique physical mechanism enables the eyebrow pencil of this invention to achieve an extremely smooth experience of "one-stroke application, no sticking" when drawing eyebrows.

[0059] From a chemical mechanism perspective, this cross-linked polymer has an extremely high oil absorption value. Its porous structure and silicone resin shell effectively absorb excess sebum secreted by the skin, preventing sebum from penetrating into the eyebrow makeup film and causing smudging. This dual effect contributes to both smooth application and enhanced makeup longevity in the formulation of this invention, complementing the composite film-forming system and the compounded wax-based framework.

[0060] The inventors verified the irreplaceability of the aforementioned skin feel modifier through comparative experiments. Under the same conditions as in Example 1, a control formulation omitting the skin feel modifier, an alternative formulation using an equal amount of talc, an alternative formulation using an equal amount of polymethylsilsesquioxane (organosilicone resin powder), and the formulation of Example 1 of this invention were prepared. Sensory evaluation of application smoothness (1-5 points, 5 being the best) showed that the control formulation omitting the skin feel modifier scored only 2.2 points, the alternative formulation using talc scored 2.8 points, the alternative formulation using polymethylsilsesquioxane scored 3.1 points, while Example 1 of this invention scored 4.7 points. These results clearly demonstrate that the skin feel improvement effect of the vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer selected in this invention far exceeds that of simple substitution of conventional skin feel modifiers. This effect stems from its unique core-shell spherical structure and dual-action mechanism, exhibiting unexpected technical superiority.

[0061] The amount of the skin feel modifier in the eyebrow pencil lead composition of the present invention is 1% to 5% of the total weight, preferably 1.5% to 4%, and more preferably 2% to 3%. When the amount is less than 1%, the smooth application effect is not obvious; when the amount is more than 5%, it may affect the shape retention of the lead and the color rendering of the pigment.

[0062] The plant-derived bioactive complex used in this invention is a compound of Centella asiatica extract, Portulaca oleracea extract, and Zanthoxylum piperitum fruit extract in a weight ratio of (1-2):(1-2):(1-3). The design concept of this plant complex lies in its dual protection mechanism of "defense + care"—in long-lasting eyebrow pencil products, ingredients such as film-forming agents, waxes, and colorants may cause physical or chemical irritation to the sensitive skin around the eyes. The plant complex of this invention provides comprehensive protection for the skin from two dimensions: "inhibiting irritation" and "actively promoting repair," while also gently promoting microcirculation in hair follicles and improving the eyebrow growth environment.

[0063] The functions of the three plant extracts and their synergistic effects are described below.

[0064] Centella asiatica extract: Centella asiatica, traditionally known as the "herb of longevity" or "tiger grass" in medicine, is rich in triterpenoid saponins such as Asiaticoside, Madecassoside, Asiatic acid, and Madecassic acid. These active ingredients effectively inhibit the expression of inflammatory factors (such as tumor necrosis factor-α and interleukin-6), promote fibroblast proliferation and collagen synthesis, and possess excellent soothing, anti-inflammatory, repairing, and wound-healing effects. In the long-lasting eyebrow pencil formula of this invention, Centella asiatica extract effectively neutralizes the discomfort caused by physical friction and chemical occlusion of the skin around the eyes from film-forming agents, waxes, and colorants, reducing irritation at its source.

[0065] Purslane (Portulaca oleracea) extract: Purslane is a plant used in both medicine and food, rich in flavonoids (such as quercetin, kaempferol, and luteolin), alkaloids, polyunsaturated fatty acids (especially α-linolenic acid), and polysaccharides. Modern research shows that purslane extract has significant anti-allergic, antioxidant, and moisturizing effects, and can inhibit histamine release, reducing skin redness and itching. In the formulation of this invention, purslane extract and Centella asiatica extract complement each other—Centella asiatica mainly acts downstream of the inflammatory pathway (inhibiting the expression of inflammatory factors), while purslane mainly acts upstream of the inflammatory pathway (inhibiting the release of allergic mediators). Together, they construct a protective barrier against irritation from different levels.

[0066] Zanthoxylum piperitum fruit extract: The introduction of Zanthoxylum piperitum fruit extract in this invention embodies one of the inventive concepts of the invention. Unlike plant extracts commonly found in the prior art that only have a "defense" function, Zanthoxylum piperitum fruit extract plays a unique "actively promoting" role in the formulation. Zanthoxylum piperitum fruit contains abundant alkaloids (such as sanshool, xanthool, and α-sanshool) and terpenoids, which can gently stimulate local capillary dilation, promote microcirculation in the eyebrow skin, and thus improve blood and nutrient supply to hair follicles. Long-term use of an eyebrow pencil containing Zanthoxylum piperitum fruit extract can not only complete daily eyebrow shaping but also help maintain the vitality and health of eyebrows.

[0067] The inventors have discovered that when Centella asiatica extract, Portulaca oleracea extract, and Zanthoxylum bungeanum fruit extract are combined in a weight ratio of (1-2):(1-2):(1-3), a significant synergistic effect is achieved, resulting in a bioactive synergistic effect of "1+1+1>3". To verify this synergistic effect, the inventors conducted comparative experiments using an in vitro cell model: the effects of using Centella asiatica extract, Portulaca oleracea extract, Zanthoxylum bungeanum fruit extract alone, as well as the combination formulated according to the proportions of the present invention (1:1:2), on the release of the inflammatory factor IL-1α in human keratinocytes (HaCaT cells) stimulated by sodium lauryl sulfate (SLS), and on the proliferative activity of human dermal fibroblasts (HDF) were examined. The results showed that the IL-1α inhibition rates of the three extracts used alone were 28.6%, 24.3%, and 15.2%, respectively, while the inhibition rate after compounding according to the proportions of this invention reached 68.4%, significantly higher than the simple sum of the inhibition rates of the three extracts (the sum of 68.1% was statistically significant, p<0.01). Regarding the promotion of fibroblast proliferation, the proliferation promotion rates of the three extracts used alone were 12.3%, 9.8%, and 8.2%, respectively, while the promotion rate after compounding reached 31.5%, also significantly higher than the sum of 30.3%. These in vitro experimental results fully demonstrate the synergistic effect among the three components in the plant complex of this invention.

[0068] Furthermore, in human skin patch tests, the inventors observed that after 28 consecutive days of using the eyebrow pencil products of Examples 1-6 of this invention, no subjects experienced significant adverse reactions such as erythema or itching (positive rate 0%). In contrast, the positive rate of the control formulation omitting the plant complex was 6.7%, and the positive rates of the control formulations using single Centella asiatica extract or Portulaca oleracea extract were 3.3% and 4.0%, respectively. This result further confirms the synergistic effect of the three plant extracts in reducing skin irritation.

[0069] Based on the above findings, the preferred weight ratio of Centella asiatica extract, Portulaca oleracea extract, and Zanthoxylum bungeanum fruit extract is (1-2):(1-2):(1-3), more preferably (1-1.5):(1-1.5):(1.5-2.5), and most preferably 1:1:2. The total amount of the plant-derived bioactive complex is 0.5% to 3% of the total weight of the eyebrow pencil lead composition, preferably 1% to 2.5%, and more preferably 1.5% to 2%.

[0070] The core inventiveness of this invention lies in the fact that the four technical elements mentioned above—the composite film-forming system, the compound wax-based skeleton system, the skin feel modifier, and the plant-derived bioactive complex—do not function independently, but rather produce synergistic effects through organic combination, achieving an overall performance improvement that cannot be achieved by a single element or any combination of two.

[0071] Specifically, the synergistic mechanism among the four elements is reflected in the following aspects: Synergy between the composite film-forming system and the compound wax-based framework system: The three-dimensional network film structure formed by the composite film-forming system provides a foundation for long-lasting eyebrow makeup, while the compound wax-based framework system not only provides physical structural support for the pencil lead, but the low-melting-point Japanese wax component in its crystalline network can also interact at the molecular level with polyester-5 in the composite film-forming system during application, allowing the film-forming agent to spread more evenly on the skin surface, thereby enhancing the density and adhesion of the film layer. This synergistic effect makes the eyebrow pencil of this invention significantly better than the control formulation containing only the composite film-forming system or only the compound wax base (scoring 3.2 and 2.8 points respectively) in the makeup performance test (8-hour anti-migration score above 4.5 points).

[0072] Synergy between skin feel modifier and compound wax-based framework system: The silicone elastomer powder in the skin feel modifier works together with Japanese wax on the friction interface during the application process. The former reduces rolling friction through the "micro-ball" effect, while the latter reduces sliding friction through its own low coefficient of friction. The synergy between the two makes the application smoothness score reach 4.7 or higher, while the smoothness score of the formula containing only Japanese wax without elastomer is only 4.2, and the smoothness score of the formula containing only elastomer without Japanese wax is only 4.0.

[0073] Synergy between plant-derived bioactive complexes and the composite film-forming system: The film formed by the composite film-forming system on the skin surface has a certain degree of occlusion, which may restrict the skin's "breathing" in that area, thereby increasing potential skin discomfort. However, the active ingredients in Centella asiatica and Portulaca oleracea extracts can penetrate into the skin beneath the film, actively alleviating the potential negative effects of film occlusion through anti-inflammatory and anti-allergic mechanisms. This complementary mechanism of "film occlusion" and "bioactive penetration" allows the eyebrow pencil of this invention to achieve long-lasting makeup while maintaining a 0% positive rate in skin irritation patch tests, achieving a perfect balance between long-lasting makeup and safety.

[0074] The unique synergy between Ligustrum lucidum fruit extract and two other plant extracts: Introducing Ligustrum lucidum fruit extract, which promotes microcirculation, into a long-lasting eyebrow pencil product is another inventive highlight of this invention. Unlike existing plant extract formulations that only focus on "soothing" functions, this invention achieves "care" while providing "defense"—Ligustrum lucidum fruit extract improves blood supply to hair follicles by promoting local microcirculation, which complements the soothing functions of Centella asiatica and Portulaca oleracea. This upgrades the eyebrow pencil from a simple makeup product into a multifunctional product that combines makeup and eyebrow care. This integrated "makeup + care" design concept has not been reported in the prior art and is a unique contribution of this invention.

[0075] In summary, the eyebrow pencil core composition of the present invention achieves excellent performance in four aspects simultaneously through the synergistic effect of four technical elements: makeup holding performance (waterproof, oil-proof, and anti-migration), application smoothness, mechanical strength, and low skin irritation. It successfully solves the long-standing triangular contradiction of "makeup holding-skin feel-safety" in the prior art and achieves unexpected technical results. Example 1

[0076] An eyebrow pencil lead composition comprises the following components in parts by weight: 8.0 parts polyester-5, 4.0 parts trimethylsiloxysilicate, 2.0 parts trimethylpentaphenyltrisiloxane, 6.0 parts cerescarpium, 4.0 parts oxidized polyethylene wax, 2.0 parts Japanese wax, 2.0 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 0.5 parts Centella asiatica extract, 0.5 parts Portulaca oleracea extract, 1.0 part Zanthoxylum bungeanum fruit extract, 10.0 parts CI 77499 (black iron oxide), 8.0 parts CI 77492 (yellow iron oxide), 2.0 parts CI 77491 (red iron oxide), 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0077] In this embodiment, the weight ratio of polyester-5:trimethylsiloxysilicate:trimethylpentaphenyltrisiloxane in the composite film-forming system is 4:2:1, which is within the preferred range of the present invention; the weight ratio of cerescarpium:oxidized polyethylene wax:Japanese wax in the compound wax-based system is 3:2:1, which is within the most preferred range of the present invention; and the weight ratio of Centella asiatica:purslane:Zanthoxylum bungeanum fruit in the plant complex is 0.5:0.5:1 (i.e., 1:1:2), which is also within the most preferred range of the present invention. Therefore, this embodiment represents one of the optimal implementation methods of the present invention. Example 2

[0078] An eyebrow pencil lead composition comprises the following components in parts by weight: 10.0 parts polyester-5, 5.0 parts trimethylsiloxysilicate, 3.0 parts trimethylpentaphenyltrisiloxane, 8.0 parts cerescargot, 5.0 parts oxidized polyethylene wax, 3.0 parts Japanese wax, 3.0 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 1.0 part Centella asiatica extract, 1.0 part Portulaca oleracea extract, 1.0 part Zanthoxylum bungeanum fruit extract, 12.0 parts CI 77499, 6.0 parts CI 77492, 2.0 parts CI 77491, 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0079] In this embodiment, the ratio of the composite film-forming system is 10:5:3 (approximately 3.33:1.67:1), which is within the scope of the present invention; the ratio of the compound wax-based system is 8:5:3 (approximately 2.67:1.67:1), which is within the scope of the present invention; and the ratio of the plant complex is 1:1:1, which is within the scope of the present invention. Compared with Example 1, the total amount of both the composite film-forming system and the compound wax-based system is increased in this embodiment, thus the mechanical strength and makeup-holding performance of the pen core are expected to be higher, but the smoothness of application may be slightly reduced. Actual test results show (see Table 1 below) that the mechanical strength of this embodiment is 4.2N, the highest among all embodiments, the anti-migration score after 8 hours is 4.6 points, and the smoothness of application is 4.8 points, with excellent performance in all aspects. Example 3

[0080] An eyebrow pencil lead composition comprises the following components in parts by weight: 6.0 parts polyester-5, 3.0 parts trimethylsiloxysilicate, 2.0 parts trimethylpentaphenyltrisiloxane, 5.0 parts cerescarpium, 3.0 parts oxidized polyethylene wax, 2.0 parts Japanese wax, 1.5 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 0.5 parts Centella asiatica extract, 0.5 parts Portulaca oleracea extract, 1.5 parts Zanthoxylum bungeanum fruit extract, 9.0 parts CI 77499, 9.0 parts CI 77492, 2.0 parts CI 77491, 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0081] In this embodiment, the ratio of the composite film-forming system is 6:3:2 (i.e., 3:1.5:1), which is within the scope of the present invention; the ratio of the compound wax-based system is 5:3:2 (i.e., 2.5:1.5:1), which is within the scope of the present invention; and the ratio of the plant complex is 0.5:0.5:1.5 (i.e., 1:1:3), which is within the scope of the present invention. Compared with Example 1, the relative proportion of the pepper fruit extract in this embodiment is higher, thus the expected effect in promoting hair follicle health is better, and the positive rate of the patch test is still 0%, demonstrating good safety. Example 4

[0082] An eyebrow pencil lead composition comprises the following components in parts by weight: 9.0 parts polyester-5, 6.0 parts trimethylsiloxysilicate, 4.0 parts trimethylpentaphenyltrisiloxane, 7.0 parts cerescarpium, 4.0 parts oxidized polyethylene wax, 3.0 parts Japanese wax, 4.0 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 1.0 part Centella asiatica extract, 1.0 part Portulaca oleracea extract, 1.0 part Zanthoxylum bungeanum fruit extract, 11.0 parts CI 77499, 7.0 parts CI 77492, 2.0 parts CI 77491, 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0083] In this embodiment, the ratio of the composite film-forming system is 9:6:4 (i.e., 2.25:1.5:1), which is near the lower limit of the present invention; the ratio of the compound wax-based system is 7:4:3 (i.e., 2.33:1.33:1), which is within the scope of the present invention; and the ratio of the plant complex is 1:1:1. In this embodiment, the amount of skin feel modifier is relatively high (4.0 parts), thus the smoothness of application is expected to be better. Actual test results show (see Table 1 below) that the smoothness score of application in this embodiment is 4.9 points, the highest among all embodiments. Example 5

[0084] An eyebrow pencil lead composition comprises the following components in parts by weight: 7.0 parts polyester-5, 5.0 parts trimethylsiloxysilicate, 3.0 parts trimethylpentaphenyltrisiloxane, 9.0 parts cerescargot, 6.0 parts oxidized polyethylene wax, 3.0 parts Japanese wax, 2.5 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 0.8 parts Centella asiatica extract, 0.8 parts Portulaca oleracea extract, 1.2 parts Zanthoxylum bungeanum fruit extract, 10.0 parts CI 77499, 8.0 parts CI 77492, 2.0 parts CI 77491, 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0085] In this embodiment, the total amount of the compound wax-based system is relatively high (9.0 parts of cerescargot + 6.0 parts of oxidized polyethylene wax + 3.0 parts of Japanese wax = 18.0 parts), therefore the mechanical strength of the pen refill is expected to be high. Actual test results show (see Table 1 below) that the mechanical strength of this embodiment is 4.1 N, the anti-migration score after 8 hours is 4.5 points, and all performances are well-balanced and excellent. Example 6

[0086] An eyebrow pencil lead composition comprises the following components in parts by weight: 12.0 parts polyester-5, 4.0 parts trimethylsiloxysilicate, 2.0 parts trimethylpentaphenyltrisiloxane, 6.0 parts cerescargot, 5.0 parts oxidized polyethylene wax, 2.5 parts Japanese wax, 5.0 parts vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer, 0.6 parts Centella asiatica extract, 0.6 parts Portulaca oleracea extract, 0.8 parts Zanthoxylum bungeanum fruit extract, 13.0 parts CI 77499, 5.0 parts CI 77492, 2.0 parts CI 77491, 0.2 parts tocopherol, 0.5 parts distearate dimethylammonium lithium montmorillonite, and the balance being isododecane to 100 parts.

[0087] In this embodiment, the amount of polyester-5 in the composite film-forming system is relatively high (12.0 parts), and the ratio of polyester-5:trimethylsiloxysilicate:trimethylpentaphenyltrisiloxane is 12:4:2 (i.e., 6:2:1), which is near the upper limit of the present invention; the amount of skin feel modifier is 5.0 parts, also near the upper limit. Therefore, this embodiment has unique advantages in terms of film-forming performance and application smoothness.

[0088] Preparation method: Prepare the eyebrow pencils of Examples 1-6 above according to the following steps: (i) The compound wax-based skeleton system (cerebrolysin, oxidized polyethylene wax, Japanese wax), volatile solvent (isododecane) and skin feel modifier are added to a vacuum emulsification pot with heating and stirring functions, heated to 90°C, and stirred at 200 rpm until all waxes are completely melted and mixed evenly to obtain an oil phase mixture.

[0089] (ii) Add trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane from the composite film-forming system to the oil phase mixture obtained in step (i) and stir until homogeneous. Cool to 80°C, add colorant and plant-derived bioactive complex, transfer to a three-roll mill, and grind and disperse 3 times until the slurry fineness is ≤20μm (detected by a scraper fineness gauge).

[0090] (iii) Transfer the ground material back to the emulsifying pot, cool it to 65°C, add polyester-5, tocopherol and distearate dimethylammonium lithium montmorillonite, and stir at 100 rpm for 20 minutes until completely homogeneous.

[0091] (iv) The mixture obtained in step (iii) is cast into a polytetrafluoroethylene mold in the shape of an eyebrow pencil lead at 60°C, and allowed to cool naturally to room temperature (25°C) to allow it to fully crystallize and solidify. The mold is then removed to obtain the eyebrow pencil lead.

[0092] (v) The final product is obtained by inserting the lead into the spiral propulsion mechanism of an automatic eyebrow pencil or the wooden barrel of a traditional pencil-style eyebrow pencil.

[0093] In the above preparation method, the grinding and dispersion in step (ii) is one of the key process steps. Through systematic optimization, the inventors discovered that using a three-roll mill for three grinding cycles allows the colorant and plant extracts to achieve optimal dispersion in the system, with a fineness ≤20μm. If the fineness is too high (>20μm), the lines drawn with the eyebrow pencil will appear grainy and uneven, affecting the makeup effect. While a fineness too low (<5μm) is theoretically better, in actual production, it requires longer grinding time and more grinding cycles, reducing production efficiency and increasing equipment wear. Therefore, considering all factors, ≤20μm was chosen as the quality control indicator.

[0094] Comparative Examples 1-4 To further demonstrate the synergistic effect and inventiveness of the formulation of this invention, the following comparative examples were set up. The preparation methods of Comparative Examples 1-4 are the same as those in Example 1, except that the formulation composition is different.

[0095] Comparative Example 1: Compared with Example 1, polyester-5 in the composite film-forming system was omitted, and trimethylsiloxysilicate was increased to 12 parts, trimethylpentaphenyltrisiloxane was increased to 6 parts, and the remaining components and contents were the same as in Example 1.

[0096] Comparative Example 2: Compared with Example 1, the compound wax-based skeleton system was replaced with a traditional system (5 parts carnauba wax, 8 parts beeswax, and 3 parts microcrystalline wax), while the remaining components and contents were the same as in Example 1.

[0097] Comparative Example 3: Compared with Example 1, the skin feel modifier (vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer) was omitted and replaced with an equal amount of talc. The remaining components and contents were the same as in Example 1.

[0098] Comparative Example 4: Compared with Example 1, the plant-derived bioactive complex was omitted and replaced with an equal amount of lanolin (as a traditional emollient), while the remaining components and contents were the same as in Example 1.

[0099] Comparative Example 5: A commercially available eyebrow pencil that claims to be "waterproof, sweatproof, and long-lasting" (main ingredients: hydrogenated castor oil, ceresin wax, CI77499, carnauba wax, and acrylate copolymer).

[0100] Performance testing and effect evaluation The eyebrow pencils prepared in Examples 1-6 and Comparative Examples 1-5 were subjected to the following performance tests.

[0101] 1. Mechanical strength test (pen lead hardness / breakage resistance) Test method: A three-point bending test was performed using a texture analyzer (TA.XT Plus, Stable Micro Systems, UK). A 2cm long pen refill (3mm in diameter) was placed on two fulcrums spaced 1.5cm apart. The probe was pressed down at a speed of 0.5mm / s, and the maximum force (in N) at which the pen refill broke was recorded. Ten samples were tested in each group, and the average value was taken. The results are shown in Table 1.

[0102] 2. Makeup retention performance test (waterproof, oil-proof, migration-resistant) Test Method: Thirty female volunteers aged 20-45 were recruited (15 with oily skin and 15 with combination skin). In a temperature and humidity controlled chamber (25℃, RH 50%), a 2cm long line was drawn on the inner forearm of each volunteer using a test eyebrow pencil. After drying for 1 minute, the following test was performed: Water resistance: Add 0.1ml of artificial sweat (pH 6.5), let stand for 5 minutes, then gently press with filter paper and observe the color transfer on the filter paper. Rating: A (no color transfer), B (slight color transfer), C (obvious color transfer).

[0103] Oil resistance: Add 0.1ml of artificial sebum (squalane: trioleic acid glyceride = 2:1), let stand for 10 minutes, then gently wipe once with filter paper and observe the integrity of the lines. Rating: A (lines are complete and unblemished), B (line edges are slightly blurred), C (lines are obviously blemished or broken).

[0104] Anti-migration: Volunteers wore the eyebrow pencil sample for 8 hours (normal activities, no touch-ups at midday). At 4 and 8 hours, professional makeup artists assessed the smudging area and line clarity of the eyebrow makeup. A 1-5 point scale was used for scoring (5 points: no smudging, sharp and clear lines; 1 point: severe smudging, lines almost disappear). Results are shown in Table 2.

[0105] 3. Sensory evaluation of application smoothness Test method: The 30 volunteers used the test eyebrow pencil to draw on their eyebrows and evaluated the smoothness of the application. A 1-5 scale was used (5 points: very smooth, no resistance; 1 point: very sticky, with a noticeable pulling sensation). The results are shown in Table 2.

[0106] 4. Skin irritation test Test Method: The human skin patch test method was followed as specified in the "Cosmetic Safety Technical Specifications" (2015 edition). Thirty volunteers with sensitive skin were recruited. The test sample was placed in a patch applicator and applied to the volunteers' backs for 48 hours. Skin reactions were observed at 30 minutes, 24 hours, and 48 hours after removing the patch applicator, and scored according to the standard procedure. The incidence of adverse reactions was calculated. Results are shown in Table 1.

[0107]

[0108]

[0109] Comparative Examples 6-10 To further verify the unexpected synergistic effect among the four elements of this invention, the following five comparative examples were added.

[0110] Comparative Example 6: Trimethylpentaphenyltrisiloxane was omitted from the composite film-forming system, and only trimethylsiloxysilicate and polyester-5 (weight ratio 2:1) were retained. The remaining components and contents were the same as in Example 1. This comparative example aims to verify whether trimethylpentaphenyltrisiloxane has an irreplaceable role in the composite film-forming system.

[0111] Comparative Example 7: The skin feel modifier (vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosspolymer) and the Japanese wax in the compound wax system were omitted. The remaining components and contents were the same as in Example 1. This comparative example aims to verify whether there is a synergistic effect between the skin feel modifier and the Japanese wax.

[0112] Comparative Example 8: The extract of *Zanthoxylum bungeanum* fruit in the plant-derived bioactive complex was omitted; only *Centella asiatica* extract and *Portulaca oleracea* extract (weight ratio 1:1) were retained. The remaining components and their contents were the same as in Example 1. This comparative example aims to verify the unique role of *Zanthoxylum bungeanum* fruit extract in the plant complex.

[0113] Comparative Example 9: An equal amount of isohexadecane was used instead of isododecane as the volatile solvent, while the remaining components and their contents were the same as in Example 1. This comparative example aims to verify the effect of the type of volatile solvent on product performance.

[0114] Comparative Example 10: The feeding sequence in the preparation method was changed, and polyester-5 was added together with other film-forming agents in step S2 (i.e., the stepwise cooling addition was not used). The remaining components and their contents were the same as in Example 1. This comparative example aims to verify the importance of stepwise cooling addition in the preparation method for the quality of the final product.

[0115] The test results for comparative examples 6-10 above are as follows: Comparative Example 6 (trimethylpentaphenyltrisiloxane omitted): Oil resistance rating was C, anti-migration score after 8 hours was 3.5, and application smoothness score was 3.8. Compared with Example 1, the oil resistance was significantly reduced and the anti-migration durability was greatly decreased, indicating that trimethylpentaphenyltrisiloxane makes an irreplaceable contribution to the flexibility and sebum penetration resistance of the composite film.

[0116] Comparative Example 7 (omitting the skin feel modifier and Japanese wax): The application smoothness score was only 2.5 points, while the anti-migration score after 8 hours was 3.2 points. Compared with Example 1, the smoothness decreased significantly, indicating that there is a synergistic relationship between the skin feel modifier and the Japanese wax, and the best application smoothness can only be achieved by the combined effect of the two.

[0117] Comparative Example 8 (Zanthoxylum bungeanum fruit extract omitted): The positive rate of the patch test was 3.3% (1 case), and there was no significant improvement in the condition of the eyebrow skin after 28 days of use. Compared with Example 1, the irritation was increased, and the active care function of promoting hair follicle health was lacking, indicating that Zanthoxylum bungeanum fruit extract plays a unique and irreplaceable "active care" role in the plant complex of the present invention.

[0118] Comparative Example 9 (Isohexadecane instead of isododecane): The performance was essentially the same as in Example 1, but the drying time was extended by approximately 15 seconds, and the volatile odor during application was slightly stronger. This indicates that isododecane is the preferred volatile solvent of this invention, but alternative solvents such as isohexadecane can still be used to implement this invention.

[0119] Comparative Example 10 (with altered feeding order): The slurry fineness was ≥30μm, the colorant was unevenly dispersed, color banding and streaks appeared on the pen lead, color development was uneven during application, and the mechanical strength decreased to 3.2N. This indicates that the stepwise cooling feeding process design in the preparation method of this invention has an irreplaceable technical contribution.

[0120] The test results of the above comparative examples 6-10 further confirm the synergistic effect of the various elements in the technical solution of the present invention and the importance of the preparation method.

[0121] Results analysis: Mechanical strength: The breaking force of Examples 1-3 was between 3.5-4.2N, exhibiting good stiffness and toughness, and not easily broken. In Comparative Example 2, after replacing the wax base with a traditional system, the breaking force significantly decreased to 2.8N, indicating that the specific compound wax base system of this invention (cereswax, oxidized polyethylene wax, and Japanese wax) is crucial for constructing a stable skeletal structure and enhancing the hardness of the pen lead. Although Comparative Example 1 had higher hardness, subsequent data showed that its excessive hardness sacrificed smoothness.

[0122] Makeup staying power: Water resistance: Most samples performed well, but the wax-based system in Comparative Example 2 was not dense enough, resulting in slight color transfer on the filter paper.

[0123] Oil resistance: Comparative Example 1 omitted polyester-5, resulting in a single silicone resin film that was too brittle and had poor adhesion to sebum, performing extremely poorly in the oil resistance test (Grade C). The wax-based system of Comparative Example 2 was easily dissolved by oil, also performing poorly. The commercially available product of Comparative Example 5 also showed obvious smudging. In contrast, Examples 1-3 all performed excellently (Grade A), proving that "trimethylsiloxysilicate + trimethylpentaphenyltrisiloxane + polyester-5" are indispensable and together form an effective barrier against sebum penetration.

[0124] Anti-migration properties: Examples 1-3 maintained a high score of over 4.5 after 8 hours, far exceeding all comparative examples. Of particular note is that Comparative Example 1 performed well after 4 hours, but its score dropped sharply after 8 hours, indicating insufficient film durability; while Comparative Example 5 almost completely smudged after 8 hours (2.5 points). This demonstrates that the present invention achieves an ultra-long-lasting makeup effect through the synergy between the composite film-forming system and the wax base.

[0125] Application smoothness: Examples 1-3 achieved high scores of 4.6-4.8. Comparative Example 3 omitted a specific skin feel modifier (silicone elastomer) and used talc instead, resulting in a sharp drop in smoothness score to 2.8, demonstrating that the elastomer is key to achieving a "silky" feel. Comparative Example 1 also suffered from negatively impacted smoothness due to its overly "rigid" film-forming system.

[0126] Skin irritation: The patch test positivity rate for Examples 1-3 was 0%, demonstrating extremely high safety. Comparative Example 1 (single resin system) showed one case of mild irritation; Comparative Example 4 (containing lanolin) showed two cases of irritation, as lanolin is an allergen for some sensitive individuals. Comparative Example 5, a commercially available product, showed three adverse reactions, possibly related to its film-forming agents or preservatives. This invention, by adding Centella asiatica and Portulaca oleracea extracts, effectively reduces the potential irritation risk of cosmetic formulations.

[0127] In summary, the eyebrow pencils prepared in Examples 1-6 of this invention are significantly superior to the comparative examples (including formulations omitting specific components and commercially available products) in terms of mechanical strength, makeup-holding performance (waterproof, oil-proof, and anti-migration), application smoothness, and low skin irritation. This indicates that this invention, through the specific combination and synergistic effect of four elements—"composite film-forming system (polyester-5, trimethylsiloxysilicate, trimethylpentaphenyltrisiloxane)," "composite wax-based framework system (cereswax, oxidized polyethylene wax, Japanese wax)," "skin feel modifier (vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer)," and "plant-derived bioactive complex (centella asiatica, purslane, and pepper fruit)"—successfully resolves the long-standing contradiction between "makeup-holding and skin feel / safety" in the prior art, achieving unexpected technical effects.

[0128] The inventors further conducted a 4-week consumer usage test (N=50) on the eyebrow pencil products of Examples 1-6 to evaluate their overall performance in real-world usage environments. The test results showed that 98% of the participants found the eyebrow pencil to apply smoothly without any sticking; 96% of the participants reported satisfactory makeup retention, requiring no touch-ups throughout the day; 94% of the participants reported no eye irritation or discomfort; and 92% of the participants indicated they would continue using the product and recommend it to others. These consumer test results further validate the practicality and market value of the present invention.

[0129] The eyebrow pencil composition and its preparation method provided by this invention utilize commercially available raw materials. The preparation process employs conventional steps in the cosmetics industry, such as heating, mixing, grinding, and casting, requiring no additional special equipment or complex process conditions. It is simple to operate, easy to control, and suitable for large-scale industrial production. The resulting eyebrow pencil product has broad market prospects and good industrial applicability.

[0130] The implementation principle of this invention is as follows: This invention discloses an eyebrow pencil, belonging to the field of cosmetics. This invention aims to solve the problem that existing eyebrow pencils struggle to simultaneously achieve long-lasting makeup, smooth application, and low irritation. The eyebrow pencil core composition of this invention comprises: a composite film-forming system composed of polyester-5, trimethylsiloxysilicate, and trimethylpentaphenyltrisiloxane in a specific weight ratio; a compound wax-based framework system composed of ceresin wax, oxidized polyethylene wax, and Japanese wax; a specific skin-feel modifier, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer; and a plant-derived bioactive complex composed of Centella asiatica, Portulaca oleracea, and Zanthoxylum bungeanum fruit extracts; and also includes a colorant and a volatile solvent. Through the synergistic effect of each component, the eyebrow pencil of this invention possesses excellent waterproof, oil-proof, and migration-resistant makeup-lasting properties, excellent application smoothness, good mechanical strength, and low irritation, making it suitable for sensitive skin. The preparation method is simple and suitable for industrial production.

[0131] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An eyebrow pencil, characterized in that, The eyebrow pencil lead composition comprises the following components by weight percentage: A composite film-forming system, wherein the composite film-forming system is composed of polyester-5, trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane, and the weight ratio of polyester-5, trimethylsiloxysilicate to trimethylpentaphenyltrisiloxane is (2-4):(1-3):(1-2); Based on the total weight of the composition, 10% to 25% is a compound wax-based framework system, which is composed of ceresin wax, oxidized polyethylene wax and Japanese wax; Based on the total weight of the composition, 1% to 5% of a skin feel modifier, wherein the skin feel modifier is a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer; Based on the total weight of the composition, 0.5% to 3% of a plant-derived bioactive complex, wherein the plant-derived bioactive complex is a mixture of Centella asiatica extract, Portulaca oleracea extract and Zanthoxylum bungeanum fruit extract; 15% to 30% colorant; The remainder is volatile solvent.

2. An eyebrow pencil according to claim 1, characterized in that, In the compound wax-based framework system, the weight ratio of cerescarpium, oxidized polyethylene wax and Japanese wax is (3-5):(2-4):(1-3).

3. An eyebrow pencil according to claim 1, characterized in that, In the plant-derived bioactive complex, the weight ratio of Centella asiatica extract, Portulaca oleracea extract and Zanthoxylum bungeanum fruit extract is (1-2):(1-2):(1-3).

4. An eyebrow pencil according to claim 1, characterized in that, The volatile solvent is one or more of isododecane, isohexadecane, or C13-16 isoalkanes.

5. An eyebrow pencil according to claim 1, characterized in that, The eyebrow pencil lead composition further comprises 0.1% to 2% of an antioxidant selected from one or more of tocopherol, butylated hydroxytoluene, or pentaerythritol ester.

6. An eyebrow pencil according to claim 1, characterized in that, The eyebrow pencil lead composition also contains 0.1% to 1% of a suspending agent, which is distearate dimethylammonium lithium montmorillonite or silachlor hydropyrite.

7. An eyebrow pencil according to claim 1, characterized in that, The colorant is selected from black iron oxide, yellow iron oxide, red iron oxide, and mixtures thereof.

8. A method for preparing an eyebrow pencil according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step S1: Mix the compound wax-based skeleton system, volatile solvent and skin feel modifier, heat to 85℃-95℃, stir until completely melted and mixed evenly to obtain an oil phase mixture; Step S2: Add trimethylsiloxysilicate and trimethylpentaphenyltrisiloxane from the composite film-forming system to the oil phase mixture obtained in step S1, stir evenly, cool to 75℃-85℃, add colorant and plant-derived bioactive complex, and grind and disperse to a fineness ≤20μm; Step S3: Cool down to 60℃-70℃, add polyester-5 and optional antioxidants and suspending agents, and stir evenly; Step S4: Pour the mixture obtained in step S3 into a mold, cool and solidify, demold, and obtain the eyebrow pencil lead; Step S5: Install the lead into the eyebrow pencil tube.

9. A method for preparing an eyebrow pencil according to claim 8, characterized in that, The grinding and dispersing in step S2 is carried out using a three-roll mill, and the grinding is performed 2-4 times.

10. The use of an eyebrow pencil according to any one of claims 1 to 7 in the preparation of cosmetics that promote eyebrow follicle health and reduce irritation.

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