Preparation method of collagen dry mask

Abstract

The invention discloses a preparation method of a collagen dry mask. A nanofiber membrane with a network structure formed by polyethylene oxide photo-crosslinking and collagen peptide molecular chains is developed by utilizing electrostatic spinning and photo-crosslinking technologies, the mask can be converted into a gel state after absorbing water, so that moisture is effectively locked, the moisturizing performance of the mask is improved, meanwhile, active ingredients in the mask can be effectively released, and the mask has a good application prospect. The method is simple in preparation process and free of any irritant or harmful substances, and the product is good in moisturizing and antioxidant effects and easy to industrially produce.

Description

Technical Field

[0001] The present invention relates to the field of cosmetics, and particularly to a preparation method of a photo-crosslinked collagen dry mask. Background Art

[0002] In recent years, as an important part of skin care cosmetics, the market demand for masks has been continuously increasing. Among them, sheet masks are widely favored by consumers due to their convenience. Currently, sheet masks on the market are mainly divided into two categories: traditional wet sheet masks and dry masks. Traditional wet sheet masks are composed of non-woven fabric and nutrient solution, and beauty active ingredients are stored in the nutrient solution. However, in order to extend the shelf life, such masks usually need to add chemical substances such as preservatives, and these ingredients may cause irritation to the skin and even trigger allergic reactions. In addition, the nutrient solution is mostly packaged in plastic, which not only increases resource consumption but also may cause serious environmental pollution problems. Yan Linqi et al. studied the use of preservatives in mask cosmetics and found that the proportion of marked preservatives was only 67% (37 / 55). Approximately one-third of mask cosmetics did not use preservatives, but constructed an anti-corrosion system by adding p-hydroxyacetophenone, octanoyl hydroxamic acid, etc. that are not included in the "List of Used Cosmetic Raw Materials" (2021 Edition), so as to achieve the effect of claiming "no preservatives" during sales. This research was published in the first issue of "Flavors and Fragrances of Cosmetics" in 2025, and the article title is "Use and Quality Analysis of Preservatives in Mask Cosmetics". Li Hewei et al. further explored the local skin irritation, residence amount and transdermal amount of methylparaben and p-hydroxyacetophenone. The results showed that the concentration of methylparaben in the dermis was higher than the cytotoxicity threshold at two time points, which may cause potential local skin toxicity risks. Since the effective antibacterial concentration of p-hydroxyacetophenone is close to the safe concentration, long-term application of the mask may lead to the accumulation of the residence amount in the skin, and then cause other side effects. This research was published in the second issue of the 34th volume of "Chinese Journal of Aesthetic Medicine" in 2025, and the article title is "Study on Local Skin Irritation, Residence Amount and Transdermal Amount of Preservatives Methylparaben and p-Hydroxyacetophenone".

[0003] In contrast, dry-state facial masks combine nutrient solution with base cloth through freeze-drying technology to preserve beauty nutrients in dry form, thus avoiding the use of preservatives in wet nutrient solution. At the same time, dry-state facial masks can use biodegradable paper-based packaging, further reducing the environmental burden. However, dry-state facial masks need to be dissolved and activated with liquid before use, and the operation is relatively complex. If the dissolution time is too long, some beauty ingredients may be lost into the dissolution liquid, not only causing waste of resources, but also reducing the moisturizing effect and overall efficacy of the facial mask. Chinese Patent CN202420355848.5 discloses a new type of flash-release freeze-dried facial mask, which accelerates the dissolution and activation of the facial mask cloth by opening grooves on the facial mask base cloth to prevent disintegration. However, this design will also accelerate local water loss, causing... In addition, Chinese Patent CN202311376373.4 also discloses an antibacterial nanofiber dry facial mask and its preparation method. This method stores the nutrient solution in the form of nanofibers and can be quickly dissolved in water, thus improving the convenience of use. However, its moisturizing mechanism still depends on non-woven fabric to absorb and carry liquid, and there is no essential difference from ordinary freeze-dried facial masks. Chinese Patent CN202411550520.X discloses a preparation method of a fast-dissolving recombinant collagen nanofiber facial mask. This method spins collagen and other water-soluble polymers into nanofiber facial masks on the surface of non-woven fabric, which has the characteristics of melting and dissolving instantly when encountering water, and its moisturizing function still depends on the base cloth.

[0004] In summary, aiming at the problems that existing dry facial masks mostly rely on base cloth for liquid conduction activation, water locking and moisturizing, etc., providing a dry-state facial mask that does not require a base cloth for water locking, moisturizing, and the release of active ingredients helps to meet the needs of consumers' daily facial care. Summary of the Invention

[0005] To solve the above problems, the present invention proposes a collagen nanofiber dry-state facial mask based on photocrosslinking technology. When in use, only a small amount of water needs to be sprayed on the facial mask to activate its function. In addition, a stable three-dimensional network structure is constructed through photocrosslinking, so that the facial mask is transformed into a gel state after absorbing water, thereby effectively locking in water, significantly improving the moisturizing performance of the facial mask, and the effective protein components can be gradually released.

[0006] To achieve the above object, the present invention is realized through the following technical solutions, specifically including the following steps:

[0007] S1. Using distilled water as a solvent, sequentially add 2-6 wt.% of polyethylene oxide and 2-6 wt.% of collagen peptide, and stir at room temperature for 12 h to dissolve in water to obtain a uniform mixed solution;

[0008] S2. Add polyethylene glycol diacrylate to the mixed solution obtained in step 1) according to 20-50 wt.% of the mass of polyethylene oxide, and further mix thoroughly;

[0009] S3. Add a photoinitiator to the mixed solution obtained in step S2, with the addition amount being 0.5 - 2 wt% of the mass of polyethylene oxide, and stir for a certain period of time under light - shielding conditions until a uniform spinning solution is formed.

[0010] S4. Load the spinning solution obtained in step S3 into the syringe of an electrospinning machine, and perform electrospinning under the irradiation of an ultraviolet lamp with a wavelength of 365 - 400 nm. Among them, the extrusion speed of the spinning solution is 1 - 5 mL·h -1 , the spinning voltage is 15 - 20 kV, and the receiving distance is 10 - 15 cm.

[0011] S5. Vacuum - dry the nanofiber membrane obtained in step S4 at room temperature for 24 h to obtain a photo - crosslinked collagen dry - state facial mask.

[0012] Furthermore, in step S1, the collagen peptide is type II collagen peptide from chicken breast cartilage, tilapia collagen peptide, or bovine bone collagen peptide; more preferably, it is type II collagen peptide from chicken breast cartilage.

[0013] Furthermore, in step S2, the polyethylene glycol diacrylate has a weight - average molecular weight of 400, 575, or 700, and more preferably, the weight - average molecular weight is 700.

[0014] Furthermore, in step S3, the photoinitiator can be benzophenone, I2959, 1173, or benzoin dimethyl ether, and more preferably, it is I2959: the stirring time can be 2 - 6 h.

[0015] Adopting the technical solution of the present invention has the following advantageous features:

[0016] 1) The raw materials, cross - linker, and initiator used are all green and non - toxic, and the resulting polymer is biodegradable.

[0017] 2) The synthesis method has a simple process flow, convenient operation, and low cost.

[0018] 3) It is suitable for large - scale industrial production.

[0019] 4) The solvent used is only water and does not contain any irritating organic solvents.

[0020] 5) The prepared facial mask does not contain harmful preservatives. Description of the Drawings

[0021] The attached drawing shows that the facial mask prepared in Example 1 exhibits good biocompatibility in the cytotoxicity experiment. Detailed Embodiments

[0022] To better understand the present invention, the content of the present invention will be further clarified below in conjunction with embodiments, but the content of the present invention is not limited to the following embodiments.

[0023] Example 1

[0024] Using distilled water as solvent, 3.5wt.% polyethylene oxide and 3.5wt.% chicken sternal cartilage type II collagen peptide are added in sequence, and stirred for 12h at room temperature to dissolve in water to obtain a uniform mixed solution; polyethylene glycol diacrylate with a weight average molecular weight of 700 is added to the above mixed solution at 20wt.% of the mass of polyethylene oxide, and after sufficient mixing, a photoinitiator I2959 is added in an amount of 2wt% of the mass of polyethylene oxide, and stirred for 2h under light-proof conditions until a uniform spinning solution is formed; the obtained spinning solution is loaded into a syringe of an electrospinning machine, and electrospinning is performed under irradiation of an ultraviolet lamp with a wavelength of 365nm, and the extrusion speed of the spinning solution is set to 5mL·h -i , the spinning voltage was set to 15 kV, and the receiving distance was 15 cm; finally, the nanofiber membrane was vacuum dried at room temperature for 24 h to obtain a photo-cross-linked collagen dry mask.

[0025] Example 2

[0026] Using distilled water as solvent, 3.5wt.% polyethylene oxide and 3.5wt.% chicken sternal cartilage type II collagen peptide were added in sequence, and stirred at room temperature for 12 hours to dissolve in water to obtain a uniform mixed solution; polyethylene glycol diacrylate with a weight average molecular weight of 700 was added to the above mixed solution at 30wt.% of the mass of polyethylene oxide, and after sufficient mixing, a photoinitiator I2959 was added in an amount of 2wt% of the mass of polyethylene oxide, and stirred for 3 hours under light-proof conditions until a uniform spinning solution was formed; the obtained spinning solution was loaded into a syringe of an electrospinning machine, and electrospinning was performed under irradiation of an ultraviolet lamp with a wavelength of 365nm, and the extrusion speed of the spinning solution was set to 5mL·h -1 , the spinning voltage was set to 15 kV, and the receiving distance was 15 cm; finally, the nanofiber membrane was vacuum dried at room temperature for 24 h to obtain a photo-cross-linked collagen dry mask.

[0027] Example 3

[0028] Using distilled water as solvent, 2wt.% polyethylene oxide and 4wt.% collagen peptide were added in sequence, and stirred at room temperature for 12h to dissolve in water to obtain a uniform mixed solution; polyethylene glycol diacrylate with a weight average molecular weight of 700 was added to the above mixed solution at 30wt.% of the mass of polyethylene oxide, and after sufficient mixing, 2wt% photoinitiator I2959 was added in an amount equal to the mass of polyethylene oxide, and stirred for 2h under light-proof conditions until a uniform spinning solution was formed; the obtained spinning solution was loaded into a syringe of an electrospinning machine, and electrospinning was performed under irradiation of an ultraviolet lamp with a wavelength of 400nm, and the extrusion speed of the spinning solution was set to 3mL·h-1 , the spinning voltage was set to 15 kV, and the receiving distance was 10 cm; finally, the nanofiber membrane was vacuum dried at room temperature for 24 h to obtain a photo-cross-linked collagen dry mask.

[0029] Example 4

[0030] Using distilled water as solvent, 2wt.% polyethylene oxide and 4wt.% bovine collagen peptide are added in sequence, and stirred for 12h at room temperature to dissolve in water to obtain a uniform mixed solution; polyethylene glycol diacrylate with a weight average molecular weight of 700 is added to the above mixed solution at 40wt.% of the mass of polyethylene oxide, and after sufficient mixing, a photoinitiator I2959 is added in an amount of 2wt% of the mass of polyethylene oxide, and stirred for 4h under light-proof conditions until a uniform spinning solution is formed; the obtained spinning solution is loaded into a syringe of an electrospinning machine, and electrospinning is performed under irradiation of an ultraviolet lamp with a wavelength of 400nm, and the extrusion speed of the spinning solution is set to 5mL·h -1 , the spinning voltage was set to 18 kV, and the receiving distance was 10 cm; finally, the nanofiber membrane was vacuum dried at room temperature for 24 h to obtain a photo-cross-linked collagen dry mask.

[0031] Example 5

[0032] Taking distilled water as solvent, 3.5wt.% polyethylene oxide and 3.5wt.% tilapia collagen peptide are added in sequence, and stirred for 12h at room temperature to dissolve in water to prepare a uniform mixed solution; polyethylene glycol diacrylate with a weight average molecular weight of 700 is added to the mixed solution at 40wt.% of the mass of polyethylene oxide, and after sufficient mixing, a photoinitiator 1173 with an addition amount of 1wt% of the mass of polyethylene oxide is added, and stirred for 2h under light-proof conditions until a uniform spinning solution is formed; the obtained spinning solution is loaded into a syringe of an electrospinning machine, and electrospinning is performed under irradiation of an ultraviolet lamp with a wavelength of 365nm, and the extrusion speed of the spinning solution is set to 5mL·h 1 , the spinning voltage was set to 15 kV, and the receiving distance was 10 cm; finally, the nanofiber membrane was vacuum dried at room temperature for 24 h to obtain a photo-cross-linked collagen dry mask.

[0033] The moisture absorption rate, moisturizing rate and anti-aging effect of the mask were evaluated by weighing method and DPPH free radical scavenging rate.

[0034] (1) Determination of moisture absorption rate and moisture retention rate

[0035] The nanofiber membranes were respectively cut into pieces of 5×5 cm square, weighed, and placed in glass petri dishes. The initial weight was recorded as m0. The saturated ammonium sulfate solution was placed in a sealed desiccator to maintain a relative humidity of 81%. Then the sample to be tested was introduced into this environment. After allowing the sample to equilibrate at room temperature for 30 minutes, it was taken out and immediately weighed: this mass was recorded as m1. The hygroscopicity (W1) can be calculated using Equation 1: W1 = (m1 - m0) / m0 × 100%. The above hygroscopic sample was placed in a dryer, weighed after 30 minutes, and the weight was recorded as m2. The moisturizing rate (W2) can be calculated by the equation: W2 = (m0 - m2) / m0 × 100%.

[0036] (2) Scavenging rate of DPPH on free radicals

[0037] The anti-aging effect of the facial mask can be reflected by its ability to scavenge free radicals. After placing 0.5 g of the prepared dry facial mask in 50 mL of distilled water to release collagen peptides for a period of time, 2 mL of this solution was mixed with 2 mL of DPPH solution. After sedimentation at room temperature for 30 min in the dark, the absorbance at 517 nm was measured and denoted as A1. 2 mL of DPPH solution was mixed with 2 mL of distilled water, and then the absorbance was measured and recorded as A0. In another experiment, 2 mL of the aqueous solution releasing collagen peptides was mixed with 2 mL of ethanol, and the absorbance of the mixed solution was measured and recorded as A2. The scavenging rate of DPPH on free radicals can be calculated according to the following formula: = [1 - (A1 - A2 / A0) × 100%]

[0038] The test results are shown in Table 1.

[0039] Table 1: Hygroscopicity, moisturizing rate and scavenging rate of DPPH on free radicals

[0040] Grouping Moisture absorption rate Moisture retention rate DPPH radical scavenging rate Example 1 31 18 74 Example 2 27 19 44 Example 3 19 12 72 Example 4 23 16 62 Example 5 17 14 69

[0041] Please refer to Table 1. The facial mask prepared in Example 1 not only has good water absorption and moisturizing effects, but also has a good free radical scavenging rate, reflecting a good anti-aging effect.

Claims

1. A preparation method of a dry collagen facial mask, characterized in that It includes the following steps: S1. Using distilled water as a solvent, 2 - 6 wt.% of polyethylene oxide and 2 - 6 wt.% of collagen peptide are added in sequence, and stirred at room temperature for 12 h to dissolve in water to obtain a uniform mixed solution; S2. Polyethylene glycol diacrylate is added to the mixed solution obtained in step 1) in an amount of 20 - 50 wt.% based on the mass of polyethylene oxide, and further mixed thoroughly; S3. A photoinitiator is added to the mixed solution obtained in step S2, and the addition amount is 0.5 - 2 wt% of the mass of polyethylene oxide, and stirred for a certain time under light - shielding conditions until a uniform spinning solution is formed; S4. Load the spinning solution obtained in step S3 into the syringe of an electrospinning machine, and perform electrospinning under the irradiation of an ultraviolet lamp with a wavelength of 365 - 400 nm. Among them, the extrusion speed of the spinning solution is 1 - 5 mL·h -1 , the spinning voltage is 15 - 20 kV, and the receiving distance is 10 - 15 cm; S5. The nanofiber membrane obtained in step S4 is vacuum - dried at room temperature for 24 h to obtain a photo - crosslinked collagen dry - state facial mask.

2. The preparation method of a dry collagen facial mask according to claim 1, characterized in that The collagen peptide can be one of type II collagen peptide from chicken breast cartilage, tilapia collagen peptide, and bovine bone collagen peptide.

3. The preparation method of a dry collagen facial mask according to claim 1, characterized in that The polyethylene glycol diacrylate has a weight - average molecular weight of 400, 575, or 700.

4. The preparation method of a collagen dry mask according to claim 1, characterized in that The photoinitiator can be one of benzophenone, I2959, 1173, and benzoin dimethyl ether.

5. The preparation method of a dry collagen facial mask according to claim 1, characterized in that The stirring time described in step S3 is set to 2 - 6 h.

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