Alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on MXene composites and its application

Abstract

The present invention discloses a hair dyeing method based on an alternating electrostatic layer-by-layer assembly gradient of a MXene composite and its application. The hair dyeing method comprises: S1. spraying a chitosan solution on the surface of hair to allow the chitosan solution to wrap the hair and penetrate naturally; S2. then adding Ti3C2T x @ Gallic acid compound is sprayed on the surface of hair to make Ti3C2T x Gallic acid complex wrapped hair; S3. Then chitosan solution was mixed with Ti3C2T x @ Gallic acid complex is sprayed alternately on the hair surface to make chitosan solution and Ti3C2T x @ Gallic acid complex alternately wraps the hair to form at least 5 layers of gradient composite layer; the Ti3C2T x Gallic acid complex made of Ti3C2T x It is connected with gallic acid through a C-O-Ti coordination bond; the hair dyeing method of the present invention achieves a high-efficiency and long-lasting dyeing effect, can significantly improve the smoothness of the hair surface, and enhance the mechanical properties of the hair.

Description

Technical Field

[0001] The present invention belongs to the technical field of hair dyes, and in particular relates to a method for gradient hair dyeing by alternating electrostatic layer-by-layer assembly based on a MXene composite and its application. Background Art

[0002] As consumers' demands for personal care products that are safe, functional, and environmentally friendly escalate, traditional hair dyes are facing three technical challenges: chemical toxicity risks, single functionality, and low material efficiency. Commercially available chemical hair dyes generally contain ammonia (concentration 4-6%), hydrogen peroxide (6-12%), and aniline dyes (such as paraphenylenediamine, PPD content 1-3%). Long-term use leads to scalp irritation rates as high as 12-15%. PPD has been listed as a restricted substance by the European Union. What's more serious is that the formaldehyde concentration released during the hair dyeing process can reach 200-500 ppm, far exceeding the WHO safety threshold (<0.1ppm). In terms of functionality, traditional products only focus on dyeing effects and lack additional functions such as UV protection and antistatic properties, which cannot meet the needs of modern consumers for multifunctional care.

[0003] In recent years, two-dimensional transition metal carbides (MXene) have provided new ideas for the innovation of hair dyes due to their surface modifiable groups (-O / -OH / -F end groups) and wide-spectrum light absorption (400-800 nm). x Although the (MXene) / collagen composite hair dye achieves electromagnetic shielding function (5.1dB), it has key defects: the MXene loading amount must be ≥1wt% to ensure dyeing uniformity, and the mechanical reinforcement effect is limited (the yield strength is only increased by 11.25%); and MXene causes the friction coefficient of the hair surface to increase by 42%, which is directly related to the topological reconstruction induced by the van der Waals force between MXene layers.

[0004] CN 118615172 A discloses a Ti3C2T x Preparation method and dyeing method of hair dye and CN118615173 A disclose Ti3C2T x The application in hair dyes of these two inventions is as follows: Ti3C2T3 with amino or carboxyl functional groups capped is added to the mixed base liquid of chitosan and gallic acid. x , and then prepare the hair dye, and then spray the hair dye on the hair, evenly apply it, comb it, dry it, and then dye the hair. However, the hair dyeing methods of these two inventions have the following defects: (1) Ti3C2T in the hair dye xThe sheets are stacked uncontrollably due to the effects of van der Waals and hydrogen bonds, which easily form μm-scale aggregates, affecting the hair dyeing effect; (2) disordered stacking is formed by repeated single spraying, and the hair surface is rough. Summary of the Invention

[0005] In response to the deficiencies in the above-mentioned existing technologies, a method for gradient hair dyeing by alternating electrostatic layer-by-layer assembly based on MXene composites is provided. This method not only achieves efficient and long-lasting dyeing effects, but also has excellent color fastness to washing, can significantly improve the smoothness of the hair surface, effectively enhances the mechanical properties of the hair, and at the same time has multiple significant advantages such as excellent photothermal conversion and thermal management effects, and significantly improved antistatic properties.

[0006] The object of the present invention is to provide a method for gradient hair dyeing by alternating electrostatic layer-by-layer assembly based on a MXene composite, comprising the following steps:

[0007] S1. Spray the chitosan solution onto the hair surface so that the chitosan solution wraps around the hair and penetrates naturally;

[0008] S2. Then Ti3C2T x @ Gallic acid compound is sprayed on the surface of hair to make Ti3C2T x @Gallic acid complex wraps hair;

[0009] S3. Then the chitosan solution was mixed with Ti3C2T x @ Gallic acid complex is sprayed alternately on the hair surface to make chitosan solution and Ti3C2T x Gallic acid complex alternately wraps the hair to form at least 5 layers of gradient composite layer;

[0010] The Ti3C2T x Gallic acid complex made of Ti3C2T x It is connected to gallic acid through a CO-Ti coordination bond.

[0011] In the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of the present invention, due to the inherent negative charge of the hair surface (isoelectric point pH ≈ 3.67), the positively charged amino protonated chitosan (ζ = +37.9 mV) first forms a dense basement membrane on the hair surface through electrostatic attraction; then, gallic acid reacts with Ti3C2T4 through phenolic hydroxyl groups. x The surface Ti atoms coordinate and reduce the zeta potential to -35.5 mV, and the negatively charged Ti3C2T x A potential difference of up to 73.4 mV (corrected value) is generated between the gallic acid complex and the chitosan layer, driving the two to form a gradient structure composite film through strong electrostatic self-assembly. Through the alternating spraying process, a gradient composite layer with uniform coverage of ≥5 layers is achieved.

[0012] In some embodiments of the present invention, in S1, the mass concentration of the chitosan solution is 0.1-0.5%.

[0013] In some embodiments of the present invention, in S1, the pH value of the chitosan solution is 5.0-6.0.

[0014] In some embodiments of the present invention, in S1, the chitosan solution further contains an antioxidant.

[0015] In some embodiments of the present invention, in S2, the Ti3C2T x The interlayer spacing of the gallic acid complex is 1.05 nm.

[0016] In some embodiments of the present invention, in S2, the Ti3C2T x @Characteristic peak of 002 crystal plane of gallic acid complex.

[0017] In some embodiments of the present invention, the chitosan solution is sprayed on the surface of the hair or Ti3C2T x After the gallic acid complex is sprayed on the hair surface, a drying operation is performed.

[0018] In some embodiments of the present invention, the Ti3C2T x The preparation method of the gallic acid complex comprises the following steps:

[0019] Ti3C2T x The solution was mixed with gallic acid solution to obtain Ti3C2T x @Gallic acid complex.

[0020] In some embodiments of the present invention, the Ti3C2T x The mass concentration of the solution is 0.05-0.25%.

[0021] In some embodiments of the present invention, the mass concentration of the gallic acid solution is 0.1-0.5%.

[0022] In some embodiments of the present invention, the Ti3C2T x The mass ratio of gallic acid to gallic acid is 1:0.8-1:5.

[0023] In some embodiments of the present invention, the Ti3C2T x The surface of the molecule contains at least hydroxyl groups.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The alternating electrostatic layer-by-layer gradient hair dyeing method based on MXene composites can achieve low-concentration and high-efficiency dyeing. x The dosage is small, Ti3C2T x @Ti3C2T in gallic acid x The mass concentration of Ti3C2T in CN118615172A is as low as 0.05%, which can reduce the brightness of hair by 80% and maintain the color after 20 washes>95%. x Compared with the conventional system, the material consumption is reduced by 10-20 times.

[0026] (2) The mechanical properties of the hair treated by the alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on the MXene composite of the present invention are enhanced, and the yield strength is increased by 32.5%, and the yield strength of the hair is increased from 87.174 MPa to 115.520 MPa; the tensile strength is increased by 14.4%, and the yield strength of the hair is increased from 188.196 MPa to 215.384 MPa.

[0027] (3) The surface of hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of the present invention is smooth, almost consistent with the roughness of untreated hair. In addition, the hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of the present invention also exhibits excellent UV protection and antistatic properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Ti3C2T prepared in Example 1 x Fourier transform infrared spectrum.

[0029] Figure 2 Ti3C2T prepared in Example 1 x UV-visible absorption spectrum of .

[0030] Figure 3 Ti3C2T prepared in Example 1 x Compared with Ti3C2T prepared in Example 5 x @Comparison of X-ray diffraction patterns of gallic acid complexes.

[0031] Figure 4 Ti3C2T prepared in Example 1 x Compared with Ti3C2T prepared in Example 5 x Scanning electron microscopy images of gallic acid complexes: a) surface morphology (lateral size 1-4.6 μm); b) edge layer structure; c) cross-sectional stacking state.

[0032] Figure 5Gallic acid solution, Ti3C2T prepared in Examples 1 to 3 and 5 x Dispersion, chitosan solution and Ti3C2T x @Zeta potential diagram of gallic acid complex.

[0033] Figure 6 1 is a comparison chart of the hair dyeing effects before and after the hair dyeing treatments of Examples 9 to 13.

[0034] Figure 7 The following are analysis charts of the brightness of hair before dyeing and after dyeing of Examples 9 to 13, Comparative Examples 2 to 5, and Comparative Examples 6 to 10.

[0035] Figure 8 1 is a comparison of SEM images of the treated hair in Example 10 and Comparative Example 1.

[0036] Figure 9 The figures are wash fastness test graphs of hair before dyeing and hair treated according to Examples 9 to 13.

[0037] Figure 10 Graph showing average brightness changes of hair before dyeing and hair treated in Examples 9 to 13.

[0038] Figure 11 1 is a stress-strain curve diagram of hair before dyeing and hair treated in Example 10.

[0039] Figure 12 Thermal management properties of hair before dyeing and hair treated in Example 10: a) 300W xenon lamp irradiation for 10 seconds, temperature rise of 2.3°C; b) 10 seconds after irradiation, temperature drop of 1.6°C.

[0040] Figure 13 1 is a test chart of the antistatic performance of hair before dyeing and hair treated in Example 10. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0042] Uncoated refers to hair that has not been dyed.

[0043] Example 1

[0044] This embodiment provides Ti3C2T x The preparation specifically comprises the following steps:

[0045] After stirring 1 g of lithium fluoride and 40 mL of 9 M hydrochloric acid in a polytetrafluoroethylene beaker for 30 min, 1 g of Ti3AlC2 powder was slowly added to the polytetrafluoroethylene beaker and then reacted at 40°C for 24 hours. After the reaction, the reaction solution was centrifuged (3500 rpm, 5 min) and the supernatant was discarded. Then, it was washed with deionized water several times until the pH value of the supernatant was about 6. An appropriate amount of deionized water was added to the precipitate and ultrasonicated in an ice water bath under a nitrogen atmosphere for 10 to 20 min. Finally, it was centrifuged again (3500 rpm, 10 min) and the upper dispersion was collected to obtain Ti3C2T x dispersion.

[0046] Ti3C2T prepared in this example x FTIR Figure 1 As shown, the observed -1 The absorption peak at 1655 cm -1 The peaks at , corresponding to the stretching vibration of C=O. The presence of these characteristic peaks is consistent with the previously reported Ti3C2T x The data are highly consistent, which strongly confirms that Ti3C2T x The successful synthesis and its surface is rich in expected functional groups.

[0047] Ti3C2T prepared in this example x The UV-Vis spectrum is as follows Figure 2 As shown, in the ultraviolet band range of 200~400 nm, Ti3C2T x exhibits strong absorption characteristics, which indicates that Ti3C2T x It has excellent ultraviolet absorption ability. It can be calculated that Ti3C2T x When the mass fraction of is 0.05 wt%, the absorption rate of the composite film to ultraviolet rays with a wavelength of 200-400 nm is greater than 99.9%.

[0048] Example 2

[0049] This embodiment provides the preparation of gallic acid solution, which specifically includes the following steps:

[0050] 40 mg of gallic acid was added to a glass bottle, along with 10 ml of distilled water. The solution was then sonicated for 30 min (ultrasonic temperature 40°C, ultrasonic power 180 W) to completely dissolve the gallic acid, yielding a 4 mg / ml gallic acid solution.

[0051] Example 3

[0052] This embodiment provides the preparation of chitosan solution, which specifically includes the following steps:

[0053] Add 20 mg of L-ascorbic acid to a 20 mL glass bottle, add 10 mL of distilled water, and sonicate the solution for 10 minutes using an ultrasonic disperser to dissolve the L-ascorbic acid. Subsequently, add 20 mg of chitosan and continue sonicating for 30 minutes to dissolve the chitosan, resulting in a chitosan solution with a pH of 5.0-6.0.

[0054] Example 4

[0055] This embodiment provides Ti3C2T x The preparation of the gallic acid complex specifically comprises the following steps:

[0056] Take 10 mg Ti3C2T x Add to a 20 mL glass bottle, inject 10 mL of deionized water, and vortex mix for 1 min to prepare 1 mg / ml Ti3C2T x Then, 10 ml of 4 mg / ml gallic acid solution was added and the mixed solution was vortexed for 30 s to obtain a stable Ti3C2T x @Gallic acid, in Ti3C2T x @Gallic acid, Ti3C2T x The mass concentration is 0.05%.

[0057] Example 5

[0058] This embodiment provides Ti3C2T x The preparation of the gallic acid complex is different from that of Example 4 only in that 10 mg Ti3C2T x Replaced with 20 mg Ti3C2T x , specifically including the following steps:

[0059] Take 20 mg Ti3C2T x Add to a 20 mL glass bottle, inject 10 mL of deionized water, and vortex mix for 1 min to prepare 2 mg / ml Ti3C2T x Then, 10 ml of 4 mg / ml gallic acid solution was added and the mixed solution was vortexed for 30 s to obtain a stable Ti3C2T x @Gallic acid, in Ti3C2T x @Gallic acid, Ti3C2T x The mass concentration is 0.1%.

[0060] Depend on Figure 3 It can be seen that the Ti3C2T prepared in Example 1 x The characteristic peak (002) is located at 6.06°, which is from Ti3C2T x The characteristic peaks of Ti3C2T x The typical crystal phase of Ti3C2T prepared in Example 5 effectively eliminates the possibility of residual MAX phase or other impurities in the synthesis process, ensuring the purity of the material. x The characteristic peak of gallic acid (002) is located at 6.26 o , calculated by the Bragg equation, Ti3C2T x @The d spacing of the crystal plane of gallic acid is larger than that of pure Ti3C2T x The d spacing of Ti3C2T is reduced by 0.048 nm, which proves that the addition of gallic acid x The nanosheets become ordered and dense during the stacking process.

[0061] Depend on Figure 4 It can be seen that Ti3C2T x It has a two-dimensional layered structure, and the lateral size of a single piece is roughly in the range of 1~4.6 μm. This morphological characteristic helps it to be evenly distributed on the surface of hair.

[0062] Depend on Figure 5 It can be seen that the gallic acid solution, Ti3C2T x Dispersion, Ti3C2T x The zeta potentials of the gallic acid complex and chitosan solution were -20.9 mV, -40.31 mV, -35.5 mV, and +37.9 mV, respectively. Due to the inherent negative charge of the hair surface (isoelectric point pH ≈ 3.67), the positively charged amino protonated chitosan (ζ = +37.9 mV) first formed a dense basement membrane on the hair surface through electrostatic attraction; then, the negatively charged Ti3C2T x A potential difference of up to 73.4 mV (corrected value) is generated between the gallic acid complex (ζ=-35.5 mV) and the chitosan layer, driving the two to form a gradient structure composite film through strong electrostatic self-assembly. The alternating spraying process achieves a gradient composite layer with ≥5 layers of uniform coverage.

[0063] Example 6

[0064] This embodiment provides Ti3C2T x The preparation of the gallic acid complex is different from that of Example 4 only in that 10 mg Ti3C2T x Replaced with 30 mg Ti3C2T x , specifically including the following steps:

[0065] Take 30 mg Ti3C2T x Add to a 20 mL glass bottle, inject 10 mL of deionized water, and vortex mix for 1 min to prepare 3 mg / ml Ti3C2T x Then, 10 ml of 4 mg / ml gallic acid solution was added and the mixed solution was vortexed for 30 s to obtain a stable Ti3C2T x @Gallic acid, in Ti3C2T x @Gallic acid, Ti3C2T x The mass concentration is 0.15%.

[0066] Example 7

[0067] This embodiment provides Ti3C2T x The preparation of the gallic acid complex is different from that of Example 4 only in that 10 mg Ti3C2T x Replaced with 40 mg Ti3C2T x , specifically including the following steps:

[0068] Take 40 mg Ti3C2T x Add to a 20 mL glass bottle, inject 10 mL of deionized water, and vortex mix for 1 min to prepare 4 mg / ml Ti3C2T x Then, 10 ml of 4 mg / ml gallic acid solution was added and the mixed solution was vortexed for 30 s to obtain a stable Ti3C2T x @Gallic acid, in Ti3C2T x @Gallic acid, Ti3C2T x The mass concentration is 0.2%.

[0069] Example 8

[0070] This embodiment provides Ti3C2T x The preparation of the gallic acid complex is different from that of Example 4 only in that 10 mg Ti3C2T x Replaced with 50 mg Ti3C2T x , specifically including the following steps:

[0071] Take 50 mg Ti3C2T x Add to a 20 mL glass bottle, inject 10 mL of deionized water, and vortex mix for 1 min to prepare 5 mg / ml Ti3C2T xThen, 10 ml of 4 mg / ml gallic acid solution was added and the mixed solution was vortexed for 30 s to obtain a stable Ti3C2T x @Gallic acid, in Ti3C2T x @Gallic acid, Ti3C2T x The mass concentration is 0.25%.

[0072] Example 9

[0073] This embodiment provides a method for gradient hair dyeing by alternating electrostatic layer-by-layer assembly based on a MXene composite, which specifically includes the following steps:

[0074] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0075] S2. Then, the Ti3C2T prepared in Example 4 with a mass concentration of 0.05% x Add gallic acid to another spray bottle and repeat the spraying, combing and drying process.

[0076] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed three times, while Ti3C2T x Gallic acid was sprayed twice to form a 5-layer gradient composite layer.

[0077] Example 10

[0078] This embodiment provides a gradient hair dyeing method based on alternating electrostatic layer-by-layer assembly of MXene composites. The only difference from Example 9 is that the Ti3C2T3O4 prepared in Example 4 with a mass concentration of 0.05% is replaced with the Ti3C2T3O4 ... x @ Gallic acid" is replaced by "Ti3C2T3 prepared in Example 5 with a mass concentration of 0.1% x @ Gallic acid", specifically including the following steps:

[0079] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0080] S2. Then, the Ti3C2T prepared in Example 5 with a mass concentration of 0.1% x Add gallic acid to another spray bottle and repeat the spraying, combing and drying process.

[0081] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed three times, while Ti3C2T x Gallic acid was sprayed twice to form a 5-layer gradient composite layer.

[0082] Example 11

[0083] This embodiment provides a gradient hair dyeing method based on alternating electrostatic layer-by-layer assembly of MXene composites. The only difference from Example 9 is that the Ti3C2T3O4 prepared in Example 4 with a mass concentration of 0.05% is replaced with the Ti3C2T3O4 ... x @ Gallic acid" is replaced by "Ti3C2T3 prepared in Example 6 with a mass concentration of 0.15% x @ Gallic acid", specifically including the following steps:

[0084] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0085] S2. Then, the Ti3C2T prepared in Example 6 with a mass concentration of 0.15% x Add gallic acid to another spray bottle and repeat the spraying, combing and drying process.

[0086] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed three times, while Ti3C2T x Gallic acid was sprayed twice to form a 5-layer gradient composite layer.

[0087] Example 12

[0088] This embodiment provides a gradient hair dyeing method based on alternating electrostatic layer-by-layer assembly of MXene composites. The only difference from Example 9 is that the Ti3C2T3O4 prepared in Example 4 with a mass concentration of 0.05% is replaced with the Ti3C2T3O4 ... x @ Gallic acid" is replaced by "Ti3C2T3 prepared in Example 7 with a mass concentration of 0.2% x @ Gallic acid", specifically including the following steps:

[0089] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0090] S2. Then, the Ti3C2T prepared in Example 7 with a mass concentration of 0.2% x@Pour gallic acid into another spray bottle and repeat the above process of spraying, combing and drying;

[0091] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed three times, while Ti3C2T x Gallic acid was sprayed twice to form a 5-layer gradient composite layer.

[0092] Example 13

[0093] This embodiment provides a gradient hair dyeing method based on alternating electrostatic layer-by-layer assembly of MXene composites. The only difference from Example 9 is that the Ti3C2T3O4 prepared in Example 4 with a mass concentration of 0.05% is replaced with the Ti3C2T3O4 ... x @ Gallic acid" is replaced by "Ti3C2T3 prepared in Example 8 with a mass concentration of 0.25% x @ Gallic acid", specifically including the following steps:

[0094] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0095] S2. Then, the Ti3C2T prepared in Example 8 with a mass concentration of 0.25% x Add gallic acid to another spray bottle and repeat the spraying, combing and drying process.

[0096] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed three times, while Ti3C2T x Gallic acid was sprayed twice to form a 5-layer gradient composite layer.

[0097] Depend on Figure 6 It can be seen that the alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on the MXene composite of Example 9 is used, and Ti3C2T x @Ti3C2T in gallic acid x When the mass concentration was 0.05 wt%, the hair color was successfully transformed into a dark black tone, demonstrating an excellent coloring effect.

[0098] Comparative Example 1

[0099] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0100] S1. Slowly pour the chitosan solution prepared in Example 3 into a 20 mL spray bottle and gently and evenly spray the hair surface, ensuring that every hair strand is carefully coated. After the solution has naturally penetrated, carefully comb the hair and place it in a dryer to dry and set.

[0101] S2. Then, the Ti3C2T prepared in Example 5 with a mass concentration of 0.1% x Add gallic acid to another spray bottle and repeat the spraying, combing and drying process.

[0102] S3. Steps S1 and S2 were performed alternately. During the whole process, chitosan solution was sprayed twice. Ti3C2T x Gallic acid was sprayed twice to form a 4-layer gradient composite layer.

[0103] Comparative Example 2

[0104] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0105] S1. Prepare Ti3C2T x The dispersion was prepared with a mass concentration of 0.1%, and the chitosan solution prepared in Example 3 and the Ti3C2T x Slowly pour the liquid into a 20mL spray bottle, mix thoroughly, and then gently spray evenly on the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0106] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0107] Comparative Example 3

[0108] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0109] S1. Prepare Ti3C2T x The dispersion was prepared with a mass concentration of 0.2%, and the chitosan solution prepared in Example 3 and the Ti3C2T x Slowly pour the liquid into a 20mL spray bottle, mix thoroughly, and then gently spray evenly on the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0110] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0111] Comparative Example 4

[0112] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0113] S1. Prepare Ti3C2T x The dispersion was prepared with a mass concentration of 0.5%, and the chitosan solution prepared in Example 3 and the Ti3C2T x Slowly pour the liquid into a 20mL spray bottle, mix thoroughly, and then gently spray evenly on the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0114] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0115] Comparative Example 5

[0116] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0117] S1. Prepare Ti3C2T x The dispersion was prepared with a mass concentration of 1%, and the chitosan solution prepared in Example 3 and the Ti3C2T x Slowly pour the liquid into a 20mL spray bottle, mix thoroughly, and then gently spray evenly on the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0118] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0119] Comparative Example 6

[0120] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0121] S1. The chitosan solution prepared in Example 3 and the Ti3C2T prepared in Example 4 with a mass concentration of 0.05% x Slowly inject gallic acid into a 20mL spray bottle, mix thoroughly, and then gently and evenly spray the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0122] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0123] Comparative Example 7

[0124] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0125] S1. The chitosan solution prepared in Example 3 and the Ti3C2T prepared in Example 5 with a mass concentration of 0.1% x Slowly inject gallic acid into a 20mL spray bottle, mix thoroughly, and then gently and evenly spray the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0126] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0127] Comparative Example 8

[0128] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0129] S1. The chitosan solution prepared in Example 3 and the Ti3C2T prepared in Example 6 with a mass concentration of 0.15% x Slowly inject gallic acid into a 20mL spray bottle, mix thoroughly, and then gently and evenly spray the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0130] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0131] Comparative Example 9

[0132] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0133] S1. The chitosan solution prepared in Example 3 and the Ti3C2T prepared in Example 7 with a mass concentration of 0.2% x Slowly inject gallic acid into a 20mL spray bottle, mix thoroughly, and then gently and evenly spray the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0134] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0135] Comparative Example 10

[0136] This comparative example provides a hair dyeing method, which specifically comprises the following steps:

[0137] S1. The chitosan solution prepared in Example 3 and the Ti3C2T prepared in Example 8 with a mass concentration of 0.25% xSlowly inject gallic acid into a 20mL spray bottle, mix thoroughly, and then gently and evenly spray the hair surface, ensuring that every hair is carefully coated. After it has naturally penetrated, comb it carefully and send it to the dryer to dry and set.

[0138] S2. Repeat the entire process of step S1 5 times to form 5 composite layers.

[0139] like Figure 7 To further quantify the color change after hair dyeing, Adobe Photoshop software was used to analyze the Ti3C2T x @Ti3C2T in gallic acid x The brightness of hair treated with different concentrations of Figure 7 As shown in a, the Ti3C2T x @Ti3C2T in gallic acid x The average brightness of the hair after treatment with different mass concentrations (0.05wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%) of MXene significantly decreased by more than 80%, which shows that the alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on MXene composites of the present invention has significant coloring efficiency and color adhesion ability. In order to further verify the superiority of the alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on MXene composites of the present invention, the images of the dyeing effects of Comparative Examples 2 to 5 and Comparative Examples 6 to 10 were analyzed by using Adobe Photoshop software. Further comparative studies show that under the same formula system, the new hair dyeing process used in Examples 9 to 13 can produce more significant brightness regulation effects than the traditional hair dyeing methods of Comparative Examples 6 to 10. For specific quantitative data, see Figure 7 a, 7b Chromaticity analysis results. Among them, the parallel experiment of Example 10 and Comparative Example 2 shows that the optimized hair dyeing method can increase the brightness reduction by 27%. It is particularly noteworthy that the hair dyeing effect of Example 10 of the present invention is close to that of Comparative Example 5, while Ti3C2T x The mass concentration of MXene composites was reduced by a factor of 10. These data not only demonstrate that the present invention's alternating electrostatic layer-by-layer gradient hair dyeing method based on MXene composites can achieve efficient dyeing results at low concentrations, but also highlight its lower material usage and superior dyeing performance compared to existing technologies. This invention not only reduces production costs but also maintains excellent dyeing results.

[0140] like Figure 8As shown, 8a is a SEM image of hair before dyeing, 8b is a SEM image of hair dyed using the hair dyeing method of Comparative Example 1, and 8c is a SEM image of hair dyed using the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10. The results show that: ① Before dyeing: The original hair surface showed a natural smooth state (see Figure 8 a); ② the hair surface treated by the hair dyeing method of Comparative Example 1 forms a uniform coating (see Figure 8 b), but compared with the original hair before dyeing, the hair dyeing method of Comparative Example 1 increases the surface roughness of the hair, which is mainly due to the Ti3C2T x The nanosheets are physically stacked by van der Waals forces and hydrogen bonds between edge functional groups (-OH / -F), and the charge orientation has not yet been completed, resulting in random distribution of the sheet orientation; ③ The alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on the MXene composite of Example 10 is used: After the chitosan solution is sprayed on the outermost layer (see Figure 8 c) SEM images show that the roughness of the hair surface is significantly reduced, almost returning to its original smoothness before dyeing. This shows that spraying the chitosan solution on the outermost layer can keep the hair smoother after dyeing.

[0141] like Figure 9 As shown, the dye durability of the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing methods of Examples 9-13 was evaluated as follows: the dyed hair sample was completely immersed in a 50 mL Erlenmeyer flask containing 40 mL of 5% (v / v) shampoo. The hair was vortexed for 30 seconds each time, then rinsed with water and dried. This process was repeated 20 times to simulate the dye durability under long-term washing and conditioning conditions. After multiple washes, the hair retained its original black color, demonstrating the excellent wash fastness of the gallic acid-dyed hair.

[0142] like Figure 10 To further quantitatively analyze the durability of hair dyeing, the brightness change was evaluated by comparing the average RGB values ​​of the hair samples before and after shampooing. The average brightness of the hair samples obtained by the hair dyeing methods of Examples 9 to 13 after 20 shampooing was calculated. The small brightness change amplitude proved that the Ti3C2T x @Ti3C2T in gallic acid x The alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on MXene composites with different mass concentrations has excellent wash resistance.

[0143] like Figure 11As shown, referring to the test standard: ISO 5079:2020, after treating the hair with the alternating electrostatic layer-by-layer assembly gradient hair dyeing method based on the MXene composite of Example 10, the yield strength of the hair increased from 87.174 MPa to 115.520 MPa (an increase of 32.52%), and the tensile strength increased from 188.196 MPa to 215.384 MPa (an increase of 14.45%).

[0144] like Figure 12 As shown in FIG, the thermal responses of untreated hair and hair treated by the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10 were respectively irradiated with a 300 W xenon lamp light source for 10 s. The thermal imaging results recorded by the infrared camera showed that, as shown in FIG. Figure 12 As shown in Figure 1a, the surface temperature of hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10 increased significantly. After only 10 seconds of exposure, the temperature was at least 2.3°C higher than that of untreated hair, highlighting the excellent photothermal conversion and heat conduction capabilities of the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of the present invention. Subsequently, the hair sample was heated to a temperature close to human skin temperature (approximately 37°C) under the same 300W xenon lamp illumination conditions. The light was then turned off, and the cooling process was captured using an infrared thermal imager, as shown in Figure 10. Figure 12 As shown in Figure a, it was observed that 10 seconds after the cessation of light exposure, the average temperature of the hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10 was 1.6°C lower than that of the untreated hair sample, indicating that the hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10 returned to room temperature more quickly. This series of experimental results fully demonstrates that the hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of the present invention imparts excellent thermal management effects on hair.

[0145] like Figure 13As shown, a surface DC voltmeter was used to test the electrostatic voltage of hair samples after combing them 10 times with a plastic comb to evaluate the static electricity accumulation under different treatment conditions. The hair samples were untreated hair and hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10. "Coated" represents hair treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10. The experimental results showed that the surface electrostatic voltage of the untreated hair after combing was as high as approximately 1.32 kV. However, the surface electrostatic voltage of the hair sample treated with the MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method of Example 10 was significantly reduced to only 0.21 kV, indicating that the hair dye effectively inhibited static electricity accumulation in the hair and improved the hair's antistatic properties.

[0146] The MXene composite-based alternating electrostatic layer-by-layer gradient hair dyeing method provided by this invention not only achieves efficient and long-lasting dyeing effects, but also exhibits excellent wash fastness, significantly improves hair surface smoothness, effectively enhances hair mechanical properties, and simultaneously offers excellent photothermal conversion and thermal management, as well as significantly improved antistatic properties. These properties work together to ensure the unique value of hair dyes in the personal care product field, meeting the modern consumer demand for high-quality, multifunctional beauty products.

[0147] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the specification of this application, technicians can still modify or replace the specific implementation methods of the present invention with equivalents, but these modifications or changes do not depart from the scope of protection of the pending claims of the present application.

Claims

1. A gradient hair dyeing method based on alternating electrostatic layer-by-layer assembly of MXene composites, characterized in that: The steps include: S1. Spray the chitosan solution onto the hair surface so that the chitosan solution wraps around the hair and penetrates naturally; S2. Then Ti3C2T x @ Gallic acid compound is sprayed on the surface of hair to make Ti3C2T x @Gallic acid complex wraps hair; S3. Then the chitosan solution was mixed with Ti3C2T x @ Gallic acid complex is sprayed alternately on the hair surface to make chitosan solution and Ti3C2T x Gallic acid complexes alternately wrap the hair strands to form at least five gradient composite layers, with the outermost layer being a chitosan solution. The Ti3C2T x Gallic acid complex made of Ti3C2T x It is connected to gallic acid through a CO-Ti coordination bond.

2. The hair dyeing method according to claim 1, characterized in that In S1, the mass concentration of the chitosan solution is 0.1-0.5%; The pH value of the chitosan solution is 5.0-6.

0.

3. The hair dyeing method according to claim 1, wherein In S1, the chitosan solution further contains an antioxidant.

4. The hair dyeing method according to claim 1, wherein In S2, the Ti3C2T x The interlayer spacing of the gallic acid complex is 1.05 nm.

5. The hair dyeing method according to claim 1, wherein After the chitosan solution is sprayed on the hair surface or Ti3C2T x After the gallic acid complex is sprayed on the hair surface, a drying operation is performed.

6. The hair dyeing method according to claim 1, wherein The Ti3C2T x The preparation method of the gallic acid complex comprises the following steps: Ti3C2T x The solution was mixed with gallic acid solution to obtain Ti3C2T x @Gallic acid complex.

7. The hair dyeing method according to claim 6, characterized in that The Ti3C2T x The mass concentration of the solution is 0.05-0.25%.

8. The hair dyeing method according to claim 6, characterized in that The mass concentration of the gallic acid solution is 0.1-0.5%.

9. The hair dyeing method according to claim 6, characterized in that The Ti3C2T x The mass ratio of gallic acid to gallic acid is 1:0.8-1:

5.

10. The hair dyeing method according to claim 6, characterized in that The Ti3C2T x The surface of the molecule contains at least hydroxyl groups.

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