Polyurethane oleogel, preparation method thereof and application of polyurethane oleogel in anhydrous cosmetic formula

Abstract

The invention relates to the technical field of cosmetics, in particular to polyurethane oleogel, a preparation method of the polyurethane oleogel and application of the polyurethane oleogel in an anhydrous cosmetic formula. The polyurethane oleogel is prepared from a water-dispersible polyurethane film-forming agent, volatile grease and an organic modified layered silicate thickening agent through high-speed homogenization, and solves the technical bottleneck that water-dispersible polyurethane is difficult to be directly applied to an oil wax-based anhydrous formula; and the synergistic improvement of the anti-transfer property, the smearing smoothness and the formula stability of the anhydrous cosmetic formula can be considered.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of daily cosmetics, more particularly, it relates to a polyurethane oil gel, a preparation method thereof and application thereof in anhydrous cosmetic formulations. BACKGROUND

[0002] As a core ingredient in color cosmetic products, film formers can form a thin, continuous film on the surface of the skin or lips, "locking" effective ingredients such as pigments and powders in the film, thereby effectively ensuring the long-lasting makeup and stability of color cosmetic products. Film formers are classified as oil-soluble and water-soluble based on their solubility.

[0003] The main representative of oil-soluble film formers in related technologies is silicone resin, which can provide a dry and smooth skin feel, but the film formed by silicone resin is often hard, brittle and lacks flexibility, resulting in a tight, dry and hard feeling on the lips or skin after makeup, which affects the user experience. The main representative of water-soluble film formers is polyurethane. Due to the molecular structure of polyurethane, it can form a continuous film with soft texture, excellent elasticity and excellent skin friendliness, which has obvious advantages in skin feel. However, the film former is currently only suitable for water-containing (water-based or emulsified) systems. If it is directly added to anhydrous formulation systems (or oil-wax-based systems) mainly containing silicone oil, mineral oil and synthetic esters, serious phase separation, flocculation or agglomeration will occur due to the mismatch of polarity, which cannot be uniformly dispersed, and cannot effectively form a film, thereby completely losing its function.

[0004] Therefore, there is a long-standing technical contradiction in the field: polyurethane film formers with excellent transfer resistance and soft and comfortable skin feel cannot be directly applied to anhydrous oil-based color cosmetic formulations with the highest skin feel requirements. In view of this, the present application provides a polyurethane oil gel, a preparation method thereof and application thereof. SUMMARY

[0005] To overcome the technical obstacle that water-dispersible polyurethane film formers cannot be directly applied in anhydrous oil-based cosmetics, the present application provides a polyurethane oil gel and a preparation method thereof, which can effectively "encapsulate" and stabilize water-dispersible polyurethane in the oil phase through dosage form pretreatment technology.

[0006] In a first aspect, the present application provides a polyurethane oil gel, which adopts the following technical solution: A polyurethane oil gel, which is composed of a water-dispersible polyurethane film former, a volatile oil and an organically modified layered silicate thickener in a weight ratio of 1: (1-3): (0.1-0.3).

[0007] Preferably, the water-dispersible polyurethane film former is composed of the following components in the following weight percentages: Polyurethane-35 35-45%, Methylpropanediol 1.0-1.5%, Octyldodecanol 0.2-0.3%, Phenylpropanol 0.05-0.1%, and water as the balance.

[0008] Preferably, the organically modified phyllosilicate thickening agent is selected from one or more of lithium montmorillonite, quaternary ammonium salt-18 bentonite, dimethylsilylated silica.

[0009] Preferably, the volatile oil is selected from one or more of isododecane, isohexadecane, C 9-12 alkanes.

[0010] In a second aspect, the present application provides a method for preparing a polyurethane oil gel, comprising the following steps: After dispersing the organically modified phyllosilicate thickening agent in the volatile oil, adding the water-dispersible polyurethane film-forming agent, and then homogenizing to form a uniform gel.

[0011] In a third aspect, the present application provides an anhydrous cosmetic composition comprising the polyurethane oil gel of any one of the above or the product obtained by the above method.

[0012] Preferably, the polyurethane oil gel is added in an amount of 5-20% of the total weight of the composition.

[0013] Preferably, the anhydrous cosmetic composition is composed of phase A, phase B, and phase C, and the weight fractions of the components in each phase are as follows: Phase A: Isododecane 10-12 parts; Polyisobutylene 2-4 parts; Polyglyceryl-2 triisostearate 4-6 parts; Polymethylsilsesquioxane 2-3 parts; Mica 6-8 parts; Silica 2-3 parts; Kaolin 1-3 parts; Tocopheryl acetate 0.4-0.6 parts; Colorant 3-5 parts; Phase B: Dimethicone 39-42 parts; Dimethicone crosspolymer 1-3 parts; Dimethicone / vinyl dimethicone crosspolymer 1-8 parts; Phase C: The polyurethane oil gel of any one of the above or the product obtained by the above method 10-20 parts.

[0014] In a fourth aspect, the present application provides a preparation method of anhydrous cosmetic composition, which adopts the following technical scheme: S1, the phase A is mixed and added into a three-roll mill for fine grinding; S2, the phase B is added into the main pot and mixed with the phase A; S3, the phase C is added into the main pot and mixed with the product obtained in S2.

[0015] In a fifth aspect, the present application provides an application of the polyurethane oil gel or the product obtained by the preparation method in any of the above in improving the transfer resistance and long-lasting makeup performance of cosmetics.

[0016] In summary, the present application has the following beneficial effects: 1. The present application first creates a feasible path for applying water-dispersible polyurethane film-forming agent in anhydrous cosmetic system, successfully solves the problem of direct compatibility of water phase and oil phase by preparing polyurethane oil gel as an intermediate dosage form, so that the oil gel is incorporated into the anhydrous lip gloss formula, the system is uniform and stable, there is no phase separation or polyurethane precipitation, that is, the addition and functional activation of polyurethane in the anhydrous system are realized; 2. The polyurethane oil gel provided by the present application can significantly improve the transfer resistance of anhydrous makeup, and the effect is better than that of traditional oily film-forming agent. According to the transfer resistance test, the color transfer rate is low, and the film formed by the product has soft texture and no tight feeling, avoiding the shortcomings of hard film and poor skin feeling caused by silicone film-forming agent, and realizing the balance between long-lasting makeup effect and comfortable experience; 3. The performance of the present application mainly depends on the synergistic selection and precise control of the three-phase components (polyurethane, oil, thickening agent) of the oil gel, and the core mechanism is: a) Volatile-penetration effect of carrier oil: low-polarity volatile oil (such as isododecane) volatilizes rapidly after application, not only bringing a refreshing skin feel, but also promoting the deposition of encapsulated polyurethane particles on the skin surface, accelerating their spreading and film formation; b) Structure stabilization and controlled release of thickening agent: a specific organically modified layered silicate can form a three-dimensional card house structure in low-polarity oil, which can physically trap and uniformly disperse polyurethane water droplets, preventing their aggregation, and the structure will become thin due to shear force during application, realizing the controlled release of polyurethane; c) Synergistic film formation of polyurethane: the released polyurethane particles form a continuous and flexible film after water evaporation, and based on the synergy of polyurethane, oil and thickening agent, a complete functional chain of "stable storage-precise release-high efficiency film formation" is formed; 4. The polyurethane oleogel preparation process in this application is simple, requiring only conventional homogenization equipment, and is easy to scale up for production. It has excellent practicality and versatility. The gel can be provided directly to formulators as a standardized raw material and can be conveniently added to various anhydrous lipsticks, lip glosses, foundations and other products, greatly expanding the application scenarios of polyurethane film-forming agents. Attached Figure Description

[0017] Figure 1 The state of the polyurethane oleogel in Example 1; Figure 2 The state of the polyurethane oleogel in Example 2; Figure 3 The state of the polyurethane oleogel in Example 3; Figure 4 To compare the state of the polyurethane oleogel in Preparation Example 1; Figure 5 To compare the state of the polyurethane oleogel in Preparation Example 2; Figure 6 To compare the state of the polyurethane oleogel in Preparation Example 3; Figure 7 The state of polyurethane oleogel in the blank control group; Figure 8 To compare the state of the polyurethane oleogels prepared in Examples 4-8; Figure 9 To compare the state of the polyurethane oleogel in Preparation Example 9; Figure 10 To compare the state of the polyurethane oleogel in Preparation Example 10; Figure 11 To compare the state of the polyurethane oleogel in Preparation Example 11; Figure 12 Archived charts of test data from Examples 1-3, Comparative Examples 1-3, and the control group; Figure 13 Archived diagrams of the test data for comparative examples 4-8; Figure 14 Archived data for comparative examples 9-11. Detailed Implementation

[0018] The following examples and Figures 1-14 This application will be described in further detail.

[0019] Performance testing test I To verify the stability of polyurethane oleogels, polyurethane oleogels prepared in each comparative example and control example were selected for testing. The specific standards and procedures are as follows: At least three trained evaluators independently visually inspected the fineness and uniformity of the obtained polyurethane oil gel and took photos for documentation. If all three agree that the texture is uniform and fine, mark it as ○; If the test results show layering or a rough, grainy texture, they are counted as X. The test results are subject to a single-vote veto system; if one person's result is X, it is still counted as X.

[0020] Performance Testing Test II To verify the anti-transfer properties of the oleogel composition after its addition to the cosmetic composition, the cosmetic compositions prepared in each example and comparative example were selected for testing. The specific testing steps are as follows: 1) Take 0.10±0.01g of the cosmetic sample to be tested and apply it evenly to a 4cm×4cm artificial simulated leather (simulated skin) using a latex finger cot. Let it dry at room temperature for 5 minutes. 2) Next, tightly adhere the pre-cut white lint-free paper towel to the coating area, apply a 3.354kg weight on top of it, let it stand for 5 minutes, and then remove the paper towel; 3) Evaluate the degree of color transfer by comparing and confirming the number of colored squares on the white lint-free paper. The formula for calculating the color transfer rate (δ) is: δ = (T2 / T1) × 100% Where T1 is the total number of grids in the observation area (fixed at 64 grids), T2 is the average number of stained grids (average of repeated tests), and the lower the δ value, the better the anti-transfer performance.

[0021] Preparation Examples 1-3 A polyurethane oleogel is composed of a water-dispersible polyurethane film-forming agent, volatile oils, and an organically modified layered silicate thickener. The amounts of each component (per 100g) are shown in Table 1. Table 1: Components and their masses (g) in Preparation Examples 1-3 The specifications of each component of the polyurethane film-forming agent in Table 1 are shown in Table 2: Table 2: Components and their mass (g) in polyurethane film-forming agents Water 57.5 Polyurethane-35 41 Methylpropanediol 1.2 Octanediol 0.25 Phenylpropanol 0.05 The volatile oils in Table 1 are selected from isododecane; The organic modified layered silicate thickener in Table 1 is selected from distearate dimethylamine lithium montmorillonite, which has an average particle size of 35 μm.

[0022] Comparative preparation examples 1-3 A polyurethane oleogel differs from Preparation Example 1 in that the amounts of its components are different (calculated per 100g), as shown in Table 1: Table 3: Comparison of components and their mass (g) in preparation examples 1-3 and the blank control group Polyurethane oleogels from Preparation Examples 1-3, Comparative Preparation Examples 1-3, and the blank control group were extracted and their gel fineness and uniformity were tested according to the above method. The test results are recorded in the table below.

[0023] Table 4: Performance test results of preparation examples 1-3, comparative preparation examples 1-3, and blank control group From Table 4 above and Figures 1-3 It can be seen that the oleogel compositions in Preparation Examples 1-3 are in a fine gel state, indicating that when the water-dispersible polyurethane film-forming agent, volatile oil and organic modified layered silicate thickener are composed in a weight ratio of 1:(1-3):(0.1-0.3), it can be applied in oil-based cosmetics. Comparative Preparation Examples 1-3 (corresponding to water-dispersible polyurethane film-forming agent: volatile oil = 1:4; 1:6; 2:1, respectively) and Figures 4-6 It can be seen that when the proportions of each group exceed this range, they cannot form fine gels, and there is a layering phenomenon, and some gels are rough and contain particles. It is evident that the proportions of each component also affect the fineness and uniformity of the polyurethane. Furthermore, the blank control group and... Figure 7 It can be seen that when the organic modified layered silicate thickener is omitted, it will completely separate into layers. Therefore, it can be concluded that the organic modified layered silicate thickener has an absolute effect.

[0024] Comparative preparation examples 4-8 A polyurethane oleogel differs from Preparation Example 1 in that it uses a different volatile oil, the specific selection and corresponding purchased grades of which are shown in Table 5: Table 5: Correspondence between the selection of volatile oils in comparative preparation examples 4-8 Extract the polyurethane oleogels from the comparative preparation examples 4-8 above, and test their fineness and uniformity of gel state according to the above method. The test results are recorded in the table below.

[0025] Table 6: Performance test results of comparative preparation examples 4-8 From Table 6 above and Figure 8 It can be seen that, compared with the oleogel compositions in Preparation Examples 4-8, their gel states differ significantly due to the different selection of volatile oils, and are preferably isododecane, isohexadecane, and C... 9-12 Alkanes, with their fine, non-layered gel structure, can be used in oil-based cosmetics.

[0026] Comparative preparation examples 9-11 A polyurethane oleogel differs from Preparation Example 1 in that it uses a different organic-modified layered silicate thickener, as shown in Table 7: Table 7: Correspondence between the selection of organic modified layered silicate thickeners in Comparative Preparation Examples 9-11 The polyurethane oleogels from the comparative preparation examples 9-11 were extracted, and their fineness and uniformity were tested according to the above method. The test results are recorded in the table below.

[0027] Table 8: Performance test results of comparative preparation examples 9-11 From Table 8 above and Figures 9-11 It can be seen that, compared with the oleogel compositions in Preparation Examples 9-11, the gel states differ significantly due to the different selections of organically modified layered silicate thickeners. The preferred choices are distearate dimethylamine lithium montmorillonite, quaternary ammonium salt-18 bentonite, and dimethylsilyl silica, which produce fine, non-layered gels suitable for use in oil-based cosmetics. Among these, distearate dimethylamine lithium montmorillonite is the optimal example, and the reasons for this are as follows: The organic cation is distearate dimethylammonium, which has a relatively long carbon chain (stearic acid chain is C18). In the interlayer, it is not only bound by ionic bonds, but also forms a more complex interlayer network structure due to the entanglement of the long carbon chains. The interlayer space is larger and the stability is higher. In addition, since lithium montmorillonite itself has a large interlayer spacing, and the long carbon chains of distearate dimethylammonium further expand the interlayer space, the interlayer distance is significantly increased. A porous, three-dimensional network structure similar to a "card house" can be formed between the layers, thus better accommodating and dispersing oil phase molecules.

[0028] Example 1 An anhydrous cosmetic composition, the components of which and their corresponding masses (mg) are shown in the table below: Table 9: Components and their mass (mg) in Example 1 It should be noted that the three components in phase B are actually provided by a mixture of two commercially available raw materials: DOWSIL TM 9041 Silicone Elastomer Blend is a mixture of polydimethylsiloxane and polydimethylsiloxane crosslinked polymer, wherein the proportion of polydimethylsiloxane is approximately 87.5%; RH-SEB-6066 is a mixture of polydimethylsiloxane and polydimethylsiloxane / vinyl polydimethylsiloxane crosslinked polymer, wherein polydimethylsiloxane accounts for approximately 85%; And it was prepared by the following method: S1 and A phases are mixed and ground three times with a three-roll mill until fine and uniform, then added to the main pot; S2. Add phase B to the main pot and mix it evenly with phase A. Stir at 1000 rpm for 5 minutes. S3. Add phase C to the main pot and stir with the product obtained in S2. Stir at 800 rpm for 5 minutes.

[0029] Example 2-3 An anhydrous cosmetic composition differs from Example 1 in that its polyurethane oleogel is used differently, as detailed in the table below: Table 10: Correspondence between the selection of polyurethane oilgels in Examples 2-3 Group Polyurethane oil gel selection Example 2 Prepared as in Example 2 Example 3 Prepared as in Example 3 Comparative Examples 1-3 An anhydrous cosmetic composition differs from Example 1 in that its polyurethane oleogel is used differently, as detailed in the table below: Table 11: Correspondence between the selection of polyurethane oleogel in Comparative Examples 1-3 Group Polyurethane oil gel selection Comparative Example 1 Prepared as in Comparative Example 1 Comparative Example 2 Prepared as in Comparative Example 2 Comparative Example 3 Prepared as in Comparative Example 3 Anhydrous cosmetic compositions from Examples 1-3 and Comparative Examples 1-3 were extracted and their color transfer rates were tested according to the above method. The test results are recorded in the table below.

[0030] Table 12: Performance test results of Examples 1-3, Comparative Examples 1-3, and Control Group From the table above and Figure 12 It can be seen that the anhydrous cosmetic compositions in Examples 1-3, thanks to the use of polyurethane oleogel, effectively improve the anti-transfer performance and long-lasting makeup performance of cosmetics, with a color transfer rate of only 0.013-0.080%, which is negligible compared to Comparative Examples 1-3. Based on the detailed analysis in Table 12, it can be concluded that the synergistic mechanism of this application mainly relies on the synergistic selection and precise control of the three-phase components of the oleogel (polyurethane, grease, and thickener), as detailed below: 1) The carrier oil in this application mainly has a volatile-penetration-promoting effect: by rapidly evaporating after application, it not only brings a refreshing feel to the anhydrous cosmetic, but also promotes the more tightly deposited polyurethane particles on the skin surface, accelerating its spread and film formation; 2) The thickener in this application can form a three-dimensional cardboard structure in low polarity oil through a specific organic modified layered silicate. This structure can physically imprison and evenly disperse polyurethane water droplets, preventing them from agglomerating. When applied, it will become thinner due to shear force, realizing the controlled release of polyurethane; 3) The main mechanism of polyurethane in this application is to synergistically form a film: after the water evaporates, polyurethane particles can fuse together to form a continuous and flexible film. Based on this, polyurethane, oil, and thickener work together to form a complete functional chain of "stable storage - precise release - efficient film formation".

[0031] Therefore, when the ratio of the water-dispersible polyurethane film-forming agent, volatile oil and organic modified layered silicate thickener in Comparative Examples 1-3 is unbalanced, that is, when it exceeds the preferred range of 1:(1-3):(0.1-0.3), the original synergistic effect is reduced or even lost, and it cannot meet the requirements for application in anhydrous oil-based cosmetics.

[0032] Comparative Examples 4-8 An anhydrous cosmetic composition differs from Example 1 in that its polyurethane oleogel is used differently, as detailed in the table below: Table 13: Correspondence between the selection of polyurethane oleogel in Comparative Examples 4-8 Extract the anhydrous cosmetic compositions from Comparative Examples 4-8 above, and test their color transfer rate according to the above method. Record the test results in the table below.

[0033] Table 14: Performance Test Results of Comparative Examples 4-8 From the table above and Figure 13 As can be seen, the color transfer rate of the anhydrous cosmetic compositions in Comparative Examples 4-8 is as high as 0.384-0.558%, which is significantly higher than that of Examples 1-3. This shows that the selection of volatile oils is specific under the same conditions. In detail, it can be seen that among all the volatile oils tested, Example 1 shows an overwhelming advantage. Compared with other oils, isohexadecane, due to its slightly larger molecular weight and slower evaporation rate, may have a weaker penetration-enhancing effect, thus giving the final product the lowest color transfer rate. While other silicone oils (comparative examples 6-8) can also form gels and achieve uniformity and fineness, their anti-transfer effects are significantly inferior, and the color transfer rate of their applied products is still relatively high. This may be related to the polarity and film-forming properties of silicone oils, and their synergistic effect with polyurethane is not as good as that of isododecane.

[0034] Comparative Examples 9-11 An anhydrous cosmetic composition differs from Example 1 in that its polyurethane oleogel is used differently, as detailed in the table below: Table 15: Correspondence between the selection of polyurethane oleogels in Comparative Examples 9-11 Group Polyurethane oil gel selection Comparative Example 9 Prepared as in Comparative Example 9 Comparative Example 10 Prepared as in Comparative Example 10 Comparative Example 11 Prepared as in Comparative Example 11 Extract the anhydrous cosmetic compositions from Comparative Examples 9-11 above and test their color transfer rate according to the above method. The test results are recorded in the table below.

[0035] Table 16: Performance Test Results of Comparative Examples 9-11 From the table above and Figure 14 It can be seen that the color transfer rate of the anhydrous cosmetic compositions in Comparative Examples 9-11 is as high as 0.352-0.510%, which is significantly higher than that in Examples 1-3. This shows that the selection of organic modified layered silicate thickeners is specific under the same conditions. The specific reasons are as follows: Distearate dimethylamine lithium montmorillonite, due to its lamellar structure, is more easily oriented under shearing, providing a smooth application feel. At the same time, its organic modification and compatibility with low-polarity oils are excellent, and it can build a stable network to fix aqueous droplets. This is another key to achieving the effect of the present invention.

[0036] It is evident that the choice of thickener has a significant impact on the final application performance, with Example 1 showing the best performance. Although Comparative Example 9 can form a gel, its anti-transfer effect is reduced, which may be related to the strength of its gel network in low-polarity grease and its ability to fix polyurethane particles. Comparative Example 10 did not undergo subsequent anti-transfer tests due to its layering.

[0037] Furthermore, as shown in Comparative Example 11, which uses dimethylsilyl silica as a thickener, although it can produce a gel with a uniform appearance, it causes severe pilling during application, resulting in discontinuous film and a sharp increase in color transfer rate. This proves that not all substances that can thicken oil are suitable for this system.

[0038] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A polyurethane oil gel, characterized in that, The water-dispersible polyurethane film-forming agent, volatile oil and organically modified layered silicate thickening agent are in a weight ratio of 1: (1-3) : (0.1-0.3).

2. The polyurethane oil gel according to claim 1, characterized in that, The water-dispersible polyurethane film-forming agent is composed of the following components in weight percentage: Polyurethane-35 35-45%, methylpropylene glycol 1.0-1.5%, octyl glycol 0.2-0.3%, phenylpropanol 0.05-0.1%, and water as the balance.

3. The polyurethane oil gel according to claim 1, characterized in that, The organically modified layered silicate thickening agent is selected from one or more of lithium montmorillonite, quaternary ammonium salt-18 bentonite, and dimethyl silylated silica.

4. The polyurethane oil gel according to claim 1, characterized in that, The volatile oil is selected from one or more of isododecane, isohexadecane, C 9-12 alkanes.

5. Process for the preparation of the polyurethane oil gel according to any one of claims 1 to 4, characterized in that, The method comprises the following steps: dispersing the organically modified layered silicate thickening agent in the volatile oil, then adding the water-dispersible polyurethane film-forming agent, and homogenizing to form a uniform gel.

6. An anhydrous cosmetic composition characterized in that, The polyurethane oil gel of any one of claims 1-4 or the product obtained by the preparation method of claim 5.

7. The anhydrous cosmetic composition according to Claim 6, wherein The polyurethane oil gel is added in an amount of 5-20% of the total weight of the composition.

8. The anhydrous cosmetic composition according to Claim 6, wherein The anhydrous cosmetic composition is composed of A phase, B phase and C phase, and the components in each phase are as follows in weight fraction: A phase: Isododecane 10-12 parts; Polyisobutylene 2-4 parts; Polyglyceryl-2 triisostearate 4-6 parts; Polymethylsilsesquioxane 2-3 parts; Mica 6-8 parts; Silica 2-3 parts; Kaolin 1-3 parts; Tocopheryl acetate 0.4-0.6 parts; Colorant 3-5 parts; B phase: Dimethicone 39-42 parts; Dimethicone crosslinked polymer 1-3 parts; Dimethicone / vinyl dimethicone crosslinked polymer 1-8 parts; C phase: The polyurethane oil gel of any one of claims 1-4 or the product obtained by the preparation method of claim 5 10-20 parts.

9. The method of preparing the anhydrous cosmetic composition as claimed in claim 8, characterized in that, The method comprises the following steps: S1, mix A phase and add to a three-roll mill for fine grinding; S2, add B phase to the main pot and mix with A phase; S3, add C phase to the main pot and mix with the product of S2.

10. Use of the polyurethane oil gel of any one of claims 1-4 or the product obtained by the preparation method of claim 5 in improving the transfer resistance and long-lasting makeup performance of a cosmetic.

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