A hair dyeing method for hair styling

Abstract

This invention relates to the field of beauty and hairdressing technology, specifically to a hair dyeing method for hair styling. This invention employs a precise application process, dividing the hair into sections and applying the dye to the ends first, followed by the roots, while controlling the oxidation reaction time and temperature. Finally, a special conditioner is used for color-locking treatment. This method effectively covers gray hair and produces a uniform and natural color after dyeing. The dyeing process is safe, comfortable, and non-irritating. Furthermore, this invention combines dyeing, immediate repair, and long-lasting color fixation, achieving an integrated approach from operation to effect, significantly improving the overall quality of hair styling and the user experience.

Description

Technical Field

[0001] This invention relates to the field of beauty and hairdressing technology, specifically to a hair dyeing method for hair styling. Background Technology

[0002] With the diversification of hair care needs and the improvement of health awareness, people's pursuit of hair dyeing effects has expanded from simply covering gray hair to higher requirements for color uniformity, shine, and long-lasting effect. At the same time, reducing chemical irritation during the hair dyeing process and protecting scalp health have also become core needs. Existing oxidative permanent hair dyeing technology relies on phenylenediamine dye intermediates and a strongly alkaline environment. Although it can effectively open the hair cuticle and promote dye penetration, phenylenediamine dye intermediates are common allergens, which can cause irritation reactions such as scalp itching and erythema. At the same time, the strong alkalinity and oxidation process will exacerbate the loss of hair keratin, resulting in dry, brittle hair and accelerated color fading after dyeing.

[0003] Existing dyeing methods fail to effectively integrate the three key aspects of efficient dyeing, real-time hair repair, and long-lasting pigment stabilization, resulting in significant shortcomings in overall product performance, user experience, and actual results. Therefore, developing an innovative hair dyeing method that can systematically solve the above contradictions and achieve a three-in-one approach of dyeing, hair care, and color fixation has become a key direction for breaking through current market and technological bottlenecks.

[0004] To address the above problems, the present invention provides a solution. Summary of the Invention

[0005] The purpose of this invention is to provide a hair dyeing method for hair styling that can effectively dye hair and is gentle and non-irritating.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A hair dyeing method for hair styling includes the following steps: S1: Use an analytical balance to accurately weigh the dye paste and oxide emulsion. Place the dye paste and oxide emulsion in a non-metallic mixing bowl, set the stirrer speed to 60 rpm, and stir at a constant speed for 3-5 minutes at room temperature. After stirring, a composite dye paste with a uniform texture and no particles will be obtained. S2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the hairline, earlobes and back of the neck of the person being dyed to form an isolation and protective layer; S3: Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner side of the upper arm of the person being dyed, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, and confirming that there are no allergic reactions such as erythema, papules, edema and itching, the subsequent hair dyeing operation can be carried out. S4: Use a wide-tooth comb to smooth the dry hair of the person being dyed. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. S5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 3-5 times with a wide-tooth comb. S6: After applying the dye, coil the hair on top of your head, cover it with a disposable shower cap, start the timer, and allow the oxidation reaction to proceed for 30-40 minutes at an ambient temperature of 25°C. Five minutes before the end of the reaction, randomly select a section of hair, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. S7: After the oxidation reaction is complete, immediately rinse your hair with warm water at 38-40℃ until the rinse water is colorless. Then, apply the color-locking conditioner evenly to all hair, massage for 2-3 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press and dry your hair. Avoid using shampoo within 48 hours after dyeing.

[0007] Furthermore, the mass ratio of the dye paste to the oxidative emulsion mentioned in step S1 is 1:1.5; Further, the dye paste described in step S1 is composed of the following components by weight percentage: 39.6% deionized water, 12.0% cetearyl alcohol, 8.0% caprylic / capric triglyceride, 7.0% propylene glycol, 5.0% water-soluble chitosan quaternary ammonium salt, 4.0% hydrolyzed keratin peptides, 4.0% cetearyl alcohol polyether-20, 3.5% PEG-100 stearate, 3.0% cationic sodium hyaluronate, 3 0.0% Glyceryl Stearate-PEG-75 Stearate, 2.2% Sorghum Red Extract, 2.0% Aloe Vera Gel Powder, 1.5% Henna Quinone, 1.2% Toluene-2,5-Diamine Sulfate, 1.0% Ethanolamine, 0.6% m-Aminophenol, 0.6% Aminomethylpropanol, 0.5% Dipotassium Glycyrrhizate, 0.5% Fragrance, 0.3% Disodium EDTA, 0.3% Tocopheryl Acetate, and 0.2% Mica; Furthermore, the method for preparing the dye paste includes the following steps: A1: Accurately weigh cetearyl alcohol, caprylic / capric triglyceride, cetearyl alcohol polyether-20, PEG-100 stearate, glyceryl stearate-PEG-75 stearate, and tocopheryl acetate using an analytical balance. After weighing, add them to the emulsification pot. Accurately weigh deionized water, propylene glycol, cationic sodium hyaluronate, disodium EDTA, and dipotassium glycyrrhizate using an analytical balance. After weighing, add them to the aqueous phase mixing pot. Accurately weigh toluene-2,5-diamine sulfate and m-aminophenol using an analytical balance. After weighing, dissolve them in deionized water preheated to 40°C to prepare a pre-dissolved dye solution. A2: Place the aqueous phase mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 200 rpm. Stir for 20 minutes until completely dissolved to obtain a clear aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 100 rpm to melt all the oil phase raw materials into a uniform liquid. A3: Keep the emulsifying pot at 80°C. Slowly add the clear aqueous phase into the oil phase of the emulsifying pot in a thin stream. At the same time, increase the speed of the stirrer in the emulsifying pot to 800 rpm. After all the aqueous phase has been added, keep the temperature and speed constant and continue stirring and emulsifying for 15 minutes. After the stirring and emulsification are complete, turn on the homogenizer and homogenize at 5000 rpm for 3 minutes to obtain a fine primary paste. A4: Cool the primary paste to 50℃, adjust the stirring speed to 300rpm, and add water-soluble chitosan quaternary ammonium salt, hydrolyzed keratin peptide, sorghum red extract, aloe vera gel powder, henna quinone and mica in sequence. After adding each ingredient, continue stirring for 3 minutes to ensure uniform dispersion. Then add pre-dissolved dye solution, ethanolamine and aminomethylpropanol, and continue stirring for 10 minutes at the same speed. A5: After continuous stirring, cool down to 40℃, add fragrance, set the stirrer speed to 150rpm, stir for 5min, after stirring, transfer to a vacuum degassing tank, under a vacuum of -0.08MPa, stir slowly at 50rpm for 15min to remove the air bubbles trapped in the paste. A6: After degassing, use a filling machine to dispense the product into pre-defined hair dye tubes, seal them, and place the filled product in a constant temperature environment of 25℃ for 48 hours to obtain the dye paste.

[0008] Furthermore, the oxidized emulsion described in step S1 is composed of the following components by mass percentage: 9.0% hydrogen peroxide, 84.4% deionized water, 2.5% polyquaternium-67, 1.5% tetraacetylethylenediamine, 1.0% disodium hydrogen phosphate, 0.8% disodium ethylenediaminetetraacetate, 0.3% trehalose, 0.2% panthenol, 0.1% salicylic acid, 0.1% phenoxyethanol, and 0.1% phosphoric acid; Furthermore, the method for preparing the oxidized emulsion includes the following steps: B1: Use an analytical balance to accurately weigh deionized water and add it to the preparation vessel as the aqueous phase. Store hydrogen peroxide in a special clean polyethylene container and place it separately in a ventilated and low-temperature place. Store phosphoric acid and salicylic acid in glass containers and separate them from hydrogen peroxide. B2: Add disodium hydrogen phosphate, disodium ethylenediaminetetraacetate, tetraacetylethylenediamine and salicylic acid to the main preparation vessel, start stirring and control the speed at 300 rpm, and at the same time start the water bath circulation system to heat the aqueous phase system to 35°C, and stir at a constant temperature until all raw materials are completely dissolved to obtain a clear and transparent basic aqueous phase. B3: Cool the base aqueous phase to 25°C, set the stirrer speed to 200 rpm, and stir continuously. While stirring continuously, slowly and evenly add polyquaternium-67. After the addition is complete, increase the stirring speed to 500 rpm and stir continuously for 40 minutes to obtain the premixed solution. B4: While keeping the mixture stirred, add trehalose and panthenol to the premix in sequence. Stir for 5 minutes after each ingredient is added until completely dissolved. Then, slowly add 85% of the formulated amount of phosphoric acid using a dropping funnel to initially adjust the pH value to the range of 3.0-3.5. B5: After pH adjustment, turn on the circulating water bath of the preparation vessel and adjust the temperature to 15℃. Then set the stirrer speed to 100rpm and continue to stir at low speed. Under low speed stirring, use a hydrogen peroxide-specific feed pump to slowly and steadily add hydrogen peroxide that has been pre-cooled to 8℃ into the preparation vessel. The total time for adding hydrogen peroxide is 30min. B6: After the hydrogen peroxide is added, the remaining phosphoric acid is added to the preparation vessel and then transferred to an empty homogenizer. Under a vacuum of -0.07 MPa, the mixture is homogenized at 2500 rpm for 5 minutes. After homogenization, the mixture is filtered through a 1 μm filter sieve. After filtration, the mixture is immediately filled into light-proof and pressure-resistant packaging bottles, sealed with nitrogen, and then placed in a cool environment at 20°C for 24 hours to stabilize, thus obtaining the oxidized emulsion.

[0009] Furthermore, the color-locking conditioner described in step S7 is composed of the following ingredients by weight percentage: 81.25% deionized water, 8.0% diaminopropyl polydimethylsiloxane, 3.5% cetearyl alcohol, 2.5% polyquaternium-10, 1.5% hydrolyzed soy protein, 1.2% sunflower seed oil, 1.0% phenoxyethanol-chlorophenoxyether, 0.3% citric acid, 0.3% ceramide NP, 0.2% dipotassium glycyrrhizate, 0.1% ubiquinone, 0.05% tocopheryl acetate, and 0.1% fragrance; Furthermore, the preparation method of the post-dyeing color-locking conditioner includes the following steps: C1: Accurately weigh cetearyl alcohol, diaminopropyl polydimethylsiloxane, sunflower seed oil, and tocopheryl acetate using an analytical balance and place them in an emulsifying pot. Accurately weigh deionized water, hydrolyzed soy protein, polyquaternium-10, dipotassium glycyrrhizate, ceramide NP, ubiquinone, and citric acid using an analytical balance and place them in a mixing pot. Accurately weigh phenoxyethanol-chlorophenoxyethanol and flavoring using an analytical balance and set aside. C2: Place the mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 300 rpm. Stir until all water-soluble components are completely dissolved to obtain a homogeneous aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 150 rpm to melt all oil phase raw materials into a transparent and uniform oil phase liquid. C3: Under the condition of maintaining 80℃, the homogeneous aqueous phase is slowly added to the oil phase in the emulsification pot in a thin stream. At the same time, the speed of the stirrer in the emulsification pot is increased to 1000 rpm. After all the aqueous phase is added, the temperature and speed are kept constant, and the emulsification is continuously stirred for 15 minutes. After the emulsification is completed, the homogenizer is turned on and the homogenizer is homogenized at 4000 rpm for 2 minutes to obtain a fine primary emulsion.

[0010] C4: Cool the primary emulsion to 50°C, set the stirring speed to 250 rpm, add phenoxyethanol-chlorophenoxyethanol, stir for 5 min, after stirring, continue to cool to 40°C, add fragrance, set the stirrer speed to 150 rpm, stir and mix for 10 min, then transfer to a vacuum degassing tank, under a vacuum of -0.07 MPa, stir slowly at 50 rpm for 20 min to degas, to obtain a degassed emulsion; C5: The defoaming emulsion is dispensed into packaging bottles using a filling machine and sealed. Then, it is placed in a constant temperature environment below 25°C and allowed to stand for 72 hours to mature, resulting in a color-locking hair conditioner.

[0011] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: 1: The method of this invention implements a precise step-by-step application process that first applies the dye to the ends of the hair and then to the roots, and is combined with an original plant-chemical composite dye system. This method can effectively cover gray hair while ensuring that the hair color after dyeing achieves a uniform and natural transition from the roots to the ends, significantly improving the visual quality of the dyed hair. It can effectively cover gray hair, and the hair after dyeing has good uniformity. 2: While achieving excellent hair dyeing results, this invention creates a gentle and non-irritating hair dyeing environment. The compound dye used in this invention has a primary irritation index of 0, which can effectively avoid the discomfort of scalp burning and itching commonly caused by traditional chemical hair dyes, providing users with an excellent comfortable experience and safety guarantee. 3: This invention integrates the three stages of dyeing, hair care, and color fixing into one through specific product ingredients and continuous operation steps, ensuring the continuity and superposition of the effects from dyeing to subsequent care, and realizing a one-stop overall solution for dyeing, care, and fixing, which can effectively improve the user's efficiency and final experience. Detailed Implementation

[0012] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments.

[0013] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0014] Example 1 1. Using an analytical balance, accurately weigh 120g cetearyl alcohol, 80g caprylic / capric triglyceride, 40g cetearyl alcohol polyether-20, 35g PEG-100 stearate, 30g glyceryl stearate-PEG-75 stearate, and 3g tocopheryl acetate. After weighing, add them to the emulsification pot. Using an analytical balance, accurately weigh 396g deionized water, 70g propylene glycol, 30g cationic sodium hyaluronate, 3g disodium ethylenediaminetetraacetate, and 5g dipotassium glycyrrhizate. After weighing, add them to the aqueous phase mixing pot. Using an analytical balance, accurately weigh 12g toluene-2,5-diamine sulfate and 6g m-aminophenol. After weighing, dissolve them in deionized water preheated to 40°C to prepare a pre-dissolved dye solution. 2: Place the aqueous phase mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 200 rpm. Stir for 20 minutes until completely dissolved to obtain a clear aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 100 rpm to melt all the oil phase raw materials into a uniform liquid. 3: Keep the emulsifying pot at 80°C. Slowly add the clarified aqueous phase into the oil phase in the emulsifying pot in a thin stream. At the same time, increase the speed of the stirrer in the emulsifying pot to 800 rpm. After all the aqueous phase has been added, keep the temperature and speed constant and continue stirring and emulsifying for 15 minutes. After the stirring and emulsification are complete, turn on the homogenizer and homogenize at 5000 rpm for 3 minutes to obtain a fine primary paste. 4. Cool the initial paste to 50℃, adjust the stirring speed to 300rpm, and add 50g of water-soluble chitosan quaternary ammonium salt, 40g of hydrolyzed keratin peptide, 22g of sorghum red extract, 20g of aloe vera gel powder, 15g of henna quinone and 2g of mica in sequence. After adding each ingredient, continue stirring for 3 minutes to ensure uniform dispersion. Then add the pre-dissolved dye solution, 10g of ethanolamine and 6g of aminomethylpropanol. Keep the stirring speed unchanged and continue stirring for 10 minutes. 5: After continuous stirring, cool down to 40℃, add 5g of fragrance, set the stirrer speed to 150rpm, stir for 5min, after stirring, transfer to a vacuum degassing tank, under a vacuum of -0.08MPa, stir slowly at 50rpm for 15min to remove the air bubbles trapped in the paste. 6: After degassing, use a filling machine to dispense the product into pre-defined hair dye tubes, seal them, and place the filled product in a constant temperature environment of 25°C for 48 hours to obtain the dye paste prepared in Example 1.

[0015] Example 2 1. Use an analytical balance to accurately weigh 844g of deionized water and add it to the preparation vessel as the aqueous phase. Place 90g of hydrogen peroxide in a special clean polyethylene container and store it separately in a ventilated and low-temperature place. Place 1g of phosphoric acid and 1g of salicylic acid in glass containers and store them separately from the hydrogen peroxide. 2: Add 10g disodium hydrogen phosphate, 8g disodium ethylenediaminetetraacetate, 15g tetraacetylethylenediamine and salicylic acid to the main preparation vessel, start the stirrer and control the speed at 300 rpm, and at the same time start the water bath circulation system to raise the temperature of the aqueous phase system to 35°C, and stir at a constant temperature until all raw materials are completely dissolved to obtain a clear and transparent basic aqueous phase. 3: Cool the base aqueous phase to 25℃, set the stirrer speed to 200rpm, and stir continuously. While stirring continuously, slowly and evenly add 25g of polyquaternium-67. After the addition is complete, increase the stirring speed to 500rpm and stir continuously for 40min to obtain the premixed solution. 4. While keeping the mixture stirred, add 3g of trehalose and 2g of panthenol to the premixed solution in sequence. Stir for 5 minutes after each ingredient is added until completely dissolved. Then, slowly add 0.85g of phosphoric acid using a dropping funnel to initially adjust the pH value to the range of 3.0-3.5. 5: After pH adjustment, turn on the circulating water bath of the preparation vessel and adjust the temperature to 15℃. Then set the stirrer speed to 100rpm and stir continuously at low speed. Under low speed stirring, use a hydrogen peroxide-specific feed pump to slowly and steadily add hydrogen peroxide that has been pre-cooled to 8℃ into the preparation vessel. The total time for adding hydrogen peroxide is 30min. 6: After the hydrogen peroxide was added, the remaining 0.15g of phosphoric acid and 1g of phenoxyethanol were added to the preparation vessel, and then transferred to an empty homogenizer. The mixture was homogenized at 2500rpm for 5 minutes under a vacuum of -0.07MPa. After homogenization, the mixture was filtered through a 1µm filter sieve. After filtration, the mixture was immediately filled into light-proof and pressure-resistant packaging bottles, sealed with nitrogen, and then placed in a cool environment at 20℃ for 24 hours to stabilize, thus obtaining the oxidized emulsion prepared in Example 2.

[0016] Example 3 1.0% phenoxyethanol-chlorophenoxyethanol, 0.1% fragrance 1. Using an analytical balance, accurately weigh 35g cetearyl alcohol, 80g diaminopropyl polydimethylsiloxane, 12g sunflower seed oil, and 0.5g tocopheryl acetate, and place them in an emulsifying pot. Using an analytical balance, accurately weigh 812.5g deionized water, 15g hydrolyzed soy protein, 25g polyquaternium-10, 2g dipotassium glycyrrhizate, 3g ceramide NP, 1g ubiquinone, and 3g citric acid, and place them in a mixing pot. Using an analytical balance, accurately weigh 10g phenoxyethanol-chlorophenoxyethanol and 1g flavoring, and set aside. 2: Place the mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 300 rpm. Stir until all water-soluble components are completely dissolved to obtain a homogeneous aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 150 rpm to melt all oil phase raw materials into a transparent and uniform oil phase liquid. 3: While maintaining a temperature of 80°C, slowly add the homogeneous aqueous phase into the oil phase of the emulsification tank in a thin stream. At the same time, increase the speed of the stirrer in the emulsification tank to 1000 rpm. After all the aqueous phase has been added, keep the temperature and speed constant and continue stirring and emulsifying for 15 minutes. After the emulsification is completed, turn on the homogenizer and homogenize at 4000 rpm for 2 minutes to obtain a fine primary emulsion.

[0017] 4: Cool the primary emulsion to 50°C, set the stirring speed to 250 rpm, add phenoxyethanol-chlorophenoxyethanol, stir for 5 min, after stirring, continue to cool to 40°C, add fragrance, set the stirrer speed to 150 rpm, stir and mix for 10 min, then transfer to a vacuum degassing tank, under a vacuum of -0.07 MPa, stir slowly at 50 rpm for 20 min to degas, to obtain a degassed emulsion; 5: The defoaming emulsion is dispensed into packaging bottles using a filling machine and sealed. Then, it is placed in a constant temperature environment below 25°C and allowed to stand for 72 hours to mature, thus obtaining the color-locking hair conditioner prepared in Example 3.

[0018] Example 4 In this embodiment, the hair dyer was a recruited volunteer who wanted to dye his hair. The volunteer was male, 28 years old, had slight gray hair, and wanted to dye his hair to natural black. The volunteer had no history of allergies and had a healthy scalp. 1: Accurately weigh 100g of the dye paste prepared in Example 1 and 150g of the oxidative emulsion prepared in Example 2 using an analytical balance. Place the dye paste and oxidative emulsion in a non-metallic mixing bowl, set the stirrer speed to 60 rpm, and stir at room temperature for 3 minutes. After stirring, a composite dye paste with uniform texture and no particles is obtained. 2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the volunteer's hairline, earlobes and back of the neck to form an isolation and protective layer; 3. Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner skin of the volunteer's upper arm, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, if no allergic reactions such as erythema, papules, edema, and itching are observed in the test area, the subsequent hair dyeing process can proceed. 4: Use a wide-tooth comb to smooth the volunteer's dry hair. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the mid-sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. 5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 5 times with a wide-tooth comb. 6: After applying the dye, put the hair on top of your head, cover it with a disposable shower cap, start the timer, and let it oxidize for 40 minutes at an ambient temperature of 25℃. Five minutes before the end of the reaction, randomly select a hair strand, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. 7. After the oxidation reaction is complete, immediately rinse the hair with 40°C warm water until the rinse water is colorless. Then, apply the color-locking conditioner prepared in Example 3 evenly to the entire hair, massage for 2 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press the hair dry. Avoid using shampoo within 48 hours after dyeing.

[0019] Example 5 In this embodiment, the hair dyer was a recruited female volunteer who wanted to dye her hair. The volunteer was 44 years old and had a small amount of gray hair. She wanted to dye her hair dark brown. The volunteer had no history of allergies and had a healthy scalp. 1: Accurately weigh 200g of dye paste prepared in Example 1 and 300g of oxidative emulsion prepared in Example 2 using an analytical balance. Place the dye paste and oxidative emulsion in a non-metallic mixing bowl, set the stirrer speed to 60rpm, and stir at room temperature for 5min. After stirring, a composite dye paste with uniform texture and no particles is obtained. 2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the volunteer's hairline, earlobes and back of the neck to form an isolation and protective layer; 3. Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner skin of the volunteer's upper arm, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, if no allergic reactions such as erythema, papules, edema, and itching are observed in the test area, the subsequent hair dyeing process can proceed. 4: Use a wide-tooth comb to smooth the volunteer's dry hair. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the mid-sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. 5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 5 times with a wide-tooth comb. 6: After applying the dye, put the hair on top of your head, cover it with a disposable shower cap, start the timer, and let it oxidize for 40 minutes at an ambient temperature of 25℃. Five minutes before the end of the reaction, randomly select a hair strand, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. 7. After the oxidation reaction is complete, immediately rinse the hair with 38°C warm water until the rinse water is colorless. Then, apply the color-locking conditioner prepared in Example 3 evenly to the entire hair, massage for 3 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press the hair dry. Avoid using shampoo within 48 hours after dyeing.

[0020] Comparative Example 1 The participants in this comparative study were recruited volunteers who wanted to dye their hair. The volunteers were male, 27 years old, had slight gray hair, and wished to dye their hair to natural black. The volunteers had no history of allergies and had healthy scalps. The L'Oréal Perfection Revitalizing Hair Color Cream - Natural Black, purchased from the market, was used as the hair dye in Comparison Example 1. The product number is 6955818216508. 1: Place the L'Oréal Excellence Revitalizing Hair Color Cream - Natural Black dye paste and oxidizing emulsion in a non-metallic mixing bowl, set the stirrer speed to 60 rpm, and stir at room temperature for 3 minutes at a uniform speed. After stirring, you will get a composite dye paste with a uniform texture and no particles. 2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the volunteer's hairline, earlobes and back of the neck to form an isolation and protective layer; 3. Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner skin of the volunteer's upper arm, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, if no allergic reactions such as erythema, papules, edema, and itching are observed in the test area, the subsequent hair dyeing process can proceed. 4: Use a wide-tooth comb to smooth the volunteer's dry hair. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the mid-sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. 5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 5 times with a wide-tooth comb. 6: After applying the dye, put the hair on top of your head, cover it with a disposable shower cap, start the timer, and let it oxidize for 40 minutes at an ambient temperature of 25℃. Five minutes before the end of the reaction, randomly select a hair strand, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. 7. After the oxidation reaction is complete, immediately rinse the hair with 40°C warm water until the rinse water is colorless. Then, apply the color-locking conditioner prepared in Example 3 evenly to the entire hair, massage for 2 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press the hair dry. Avoid using shampoo within 48 hours after dyeing.

[0021] Comparative Example 2 The participants in this comparative hair dyeing study were recruited volunteers who wanted to dye their hair. The volunteers were female, 42 years old, had a small amount of gray hair, and wished to dye their hair to a natural black color. The volunteers had no history of allergies and had healthy scalps. The commercially available Zhencaotang plant-based conditioning hair dye - natural black was used as the hair dye in comparison example 2. The approval number is G20100675 (National Cosmetic Special Approval Number). 1: Accurately weigh 200g of dye paste prepared in Example 1 and 300g of oxidative emulsion prepared in Example 2 using an analytical balance. Place the dye paste and oxidative emulsion in a non-metallic mixing bowl, set the stirrer speed to 60rpm, and stir at room temperature for 5min. After stirring, a composite dye paste with uniform texture and no particles is obtained. 2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the volunteer's hairline, earlobes and back of the neck to form an isolation and protective layer; 3. Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner skin of the volunteer's upper arm, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, if no allergic reactions such as erythema, papules, edema, and itching are observed in the test area, the subsequent hair dyeing process can proceed. 4: Use a wide-tooth comb to smooth the volunteer's dry hair. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the mid-sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. 5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 5 times with a wide-tooth comb. 6: After applying the dye, put the hair on top of your head, cover it with a disposable shower cap, start the timer, and let it oxidize for 40 minutes at an ambient temperature of 25℃. Five minutes before the end of the reaction, randomly select a hair strand, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. 7. After the oxidation reaction is complete, immediately rinse the hair with 38°C warm water until the rinse water is colorless. Then, apply the color-locking conditioner prepared in Example 3 evenly to the entire hair, massage for 3 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press the hair dry. Avoid using shampoo within 48 hours after dyeing.

[0022] Skin occlusion patch test The compound dye used in Example 4, the compound dye used in Example 5, the compound dye used in Comparative Example 1, and the compound dye prepared in Comparative Example 2 were taken respectively. Sixty healthy volunteers were recruited, half male and half female, aged 18-60 years, with no active skin diseases or history of hair dye allergy, and were divided into 6 groups with 10 people in each group. The first four groups were used to perform skin occlusion patch tests using the composite dye used in Example 4, the composite dye used in Example 5, the composite dye used in Comparative Example 1, and the composite dye prepared in Comparative Example 2, respectively. The last two groups were negative and positive controls. The negative control was performed using 0.9% physiological saline for the skin occlusion patch test, and the positive control was performed using 1% sodium dodecyl sulfate solution for the skin occlusion patch test. The procedure for the skin occlusion patch test was as follows: The upper back skin of volunteers was cleaned. Then, using a standard patch applicator, 0.02g of each sample was loaded onto filter paper. The patch applicators with the loaded samples were randomly applied to healthy skin on both sides of the spine on the back, sealed, and fixed. All patch applicators were removed 24 hours later. Skin reactions at each site were observed and recorded by an observer in a blinded manner at 24h, 48h, and 72h after removal. The scoring criteria were based on the "Cosmetic Safety Technical Specifications" (2015 edition) and were divided into: 0 points: No response 1 point: Mild erythema (barely visible) 2 points: Moderate erythema (clearly visible), mild edema 3 points: Severe erythema, edema, papules, vesicles Table 1. Results of skin occlusion patch test

[0023] Gray hair coverage test Before the volunteers in Examples 4, 5, Comparative Example 1 and Comparative Example 2 dyed their hair, a 5cm×5cm square test area was marked on the Baihui acupoint on the top of each volunteer's head. A high-resolution photo was taken using a digital camera with fixed white balance, aperture and focal length, and the total number of gray hairs in the area was counted (denoted as N_total). After dyeing and drying, photos were taken in the same location using the same camera and parameters. Three observers, unaware of the sample number, independently counted the number of gray hairs that were still visible in the test area of ​​the photos that were not completely covered (denoted as Nnot). Calculation: Gray hair coverage rate (%) = [(Ntotal - Nun) / Ntotal] × 100% The evaluation criteria are as follows: Excellent: Coverage rate ≥ 95% Good: 85% ≤ Opacity < 95% General: Coverage rate <85% Table 2. Results of the gray hair coverage test.

[0024] Color uniformity test The test sample is the same as the gray hair coverage test. Complete hair bundles (50 hairs per bundle, taken from the same area) were cut from the roots, middle and ends of each volunteer's dyed hair. Lay the hair strands flat on a standard white board, ensuring no overlap. Use a spectrophotometer under a D65 standard light source to measure the L*a*b* chromaticity value of each hair strand. Measure each area three times and take the average value. Calculate the color difference ΔE between the mid-lengths and roots, and between the ends and mid-lengths, respectively.

[0025] The evaluation criteria are as follows: ΔE≤2.5: Minimal color difference and excellent uniformity; 2.5 < ΔE ≤ 4.0: Color difference is faintly visible to the naked eye, and uniformity is good; ΔE > 4.0: Color difference is relatively obvious, and uniformity is average; Table 3. Results of Coloring Uniformity Test

[0026] Analysis of Tables 1-3 shows that the composite dye used in Example 4 performed comprehensively and excellently in this performance evaluation. In the skin occlusion patch test, the irritation score was 0 and the primary irritation index (PII) was 0.00, demonstrating excellent skin gentleness and safety. In terms of efficacy, the coverage rate of mild gray hair in male volunteers reached 95.0%, with an excellent rating, demonstrating reliable dyeing ability. Particularly noteworthy was the color uniformity, with color difference ΔE values ​​between the mid-length and root hair, and between the end hair and mid-length hair, being 1.8 and 2.2, respectively. The overall uniformity was rated as excellent. This indicates that the method used in Example 4 not only effectively covered gray hair but also achieved a natural and uniform color transition from the root to the end hair. Example 5 is highly consistent with Example 4, demonstrating stable performance under different dosage and hair quality conditions. Its irritation test results are also non-irritating. In the test on a small amount of gray hair in female volunteers, the gray hair coverage rate is 94.0%, which is rated as good and the coverage effect is solid. In the color uniformity test, the ΔE values ​​are 2.0 and 2.5 respectively, and the overall uniformity evaluation reaches excellent. This further confirms that the present invention can still maintain excellent color uniformity and color consistency when processing longer and more hair, avoiding the color difference problem of hair segments that may occur in common hair dye products. Comparative Example 1 exhibits typical characteristics of traditional strong chemical hair dyes, with a gray hair coverage rate of up to 97.5%, the best in this test, proving its advantages in high-efficiency coverage and strong coloring. However, there are observable shortcomings in skin gentleness and color uniformity. Skin tests showed that a few volunteers experienced mild and transient erythema reactions. Color uniformity data revealed that the color difference ΔE between the mid-length and root of the hair was 3.5, with the root color being darker than the mid-length, resulting in an unnatural color transition. Overall, the product is highly effective but compromises on gentleness and natural makeup effect. Comparative Example 2 performs in line with its market positioning as a gentle plant-based product. It has extremely low skin irritation and is at the same excellent level as the product in Example 2. The gray hair coverage rate is 90.0%, which is rated as good and can meet daily coverage needs. In terms of color uniformity, the color difference ΔE between the hair ends and the middle of the hair is 3.8, indicating that under the test conditions, the hair ends are slightly lighter in color and the color persistence is slightly inferior. The overall uniformity is rated as good. In summary, the product performs well in terms of gentleness, but there is still room for improvement in terms of coverage strength, overall color uniformity, and persistence.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A hair dyeing method for hair styling, characterized in that, Includes the following steps: S1: Use an analytical balance to accurately weigh the dye paste and oxide emulsion. Place the dye paste and oxide emulsion in a non-metallic mixing bowl, set the stirrer speed to 60 rpm, and stir at a constant speed for 3-5 minutes at room temperature. After stirring, a composite dye paste with a uniform texture and no particles will be obtained. S2: Wear PE protective gloves, lay a disposable anti-fouling pad in the hair dyeing operation area, and use a brush to evenly apply Vaseline to the hairline, earlobes and back of the neck of the person being dyed to form an isolation and protective layer; S3: Using a sterile cotton swab, apply 0.1g of the compound dye evenly to the inner side of the upper arm of the person being dyed, covering an area of ​​1cm². 2 After observing the test area at 25℃ for 48 hours, and confirming that there are no allergic reactions such as erythema, papules, edema and itching, the subsequent hair dyeing operation can be carried out. S4: Use a wide-tooth comb to smooth the dry hair of the person being dyed. Use hair clips to divide the hair into four dyeing areas: left front, right front, left back, and right back, along the line connecting the tips of the ears and the sagittal plane of the head. Then, temporarily fix the hair in each area with clips 2cm away from the roots. S5: When starting the hair dyeing process, loosen the hair below the roots (2cm). Use a hair dye brush to evenly apply the compound dye to the hair shaft and ends. Then, use the hair dye brush to evenly apply the compound dye to the mid-lengths and ends of all the hair, ensuring that the hair is completely covered by the compound dye. Finally, apply the remaining dye to the roots. After applying the remaining compound dye, gently comb all the hair 3-5 times with a wide-tooth comb. S6: After applying the dye, coil the hair on top of your head, cover it with a disposable shower cap, start the timer, and allow the oxidation reaction to proceed for 30-40 minutes at an ambient temperature of 25°C. Five minutes before the end of the reaction, randomly select a section of hair, wipe off the surface dye, and observe the degree of coloring as a reference for terminating the reaction. S7: After the oxidation reaction is complete, immediately rinse your hair with warm water at 38-40℃ until the rinse water is colorless. Then, apply the color-locking conditioner evenly to all hair, massage for 2-3 minutes, and then rinse thoroughly with warm water. After rinsing, use a dry towel to press and dry your hair. Avoid using shampoo within 48 hours after dyeing.

2. The hair dyeing method for hair styling according to claim 1, characterized in that, The mass ratio of the dye paste to the oxidizing emulsion mentioned in step S1 is 1:1.

5.

3. The hair dyeing method for hair styling according to claim 1, characterized in that, The dye paste described in step S1 comprises the following components by weight percentage: 39.6% deionized water, 12.0% cetearyl alcohol, 8.0% caprylic / capric triglyceride, 7.0% propylene glycol, 5.0% water-soluble chitosan quaternary ammonium salt, 4.0% hydrolyzed keratin peptides, 4.0% cetearyl alcohol polyether-20, 3.5% PEG-100 stearate, 3.0% cationic sodium hyaluronate, and 3.0% [other components not specified in the original text]. % Glyceryl stearate-PEG-75 stearate, 2.2% Sorghum red extract, 2.0% Aloe vera gel powder, 1.5% Henna quinone, 1.2% Toluene-2,5-diamine sulfate, 1.0% Ethanolamine, 0.6% m-aminophenol, 0.6% aminomethylpropanol, 0.5% dipotassium glycyrrhizate, 0.5% Fragrance, 0.3% disodium EDTA, 0.3% tocopheryl acetate, and 0.2% mica.

4. A hair dyeing method for hair styling according to claim 1, characterized in that, The oxidized emulsion described in step S1 consists of the following components by mass percentage: 9.0% hydrogen peroxide, 84.4% deionized water, 2.5% polyquaternium-67, 1.5% tetraacetylethylenediamine, 1.0% disodium hydrogen phosphate, 0.8% disodium ethylenediaminetetraacetate, 0.3% trehalose, 0.2% panthenol, 0.1% salicylic acid, 0.1% phenoxyethanol, and 0.1% phosphoric acid.

5. A hair dyeing method for hair styling according to claim 1, characterized in that, The color-locking conditioner described in step S7 consists of the following ingredients by weight percentage: 81.25% deionized water, 8.0% diaminopropyl polydimethylsiloxane, 3.5% cetearyl alcohol, 2.5% polyquaternium-10, 1.5% hydrolyzed soy protein, 1.2% sunflower seed oil, 1.0% phenoxyethanol-chlorophenoxyether, 0.3% citric acid, 0.3% ceramide NP, 0.2% dipotassium glycyrrhizate, 0.1% ubiquinone, 0.05% tocopheryl acetate, and 0.1% fragrance.

6. A hair dyeing method for hair styling according to claim 3, characterized in that, The method for preparing the dye paste includes the following steps: A1: Accurately weigh cetearyl alcohol, caprylic / capric triglyceride, cetearyl alcohol polyether-20, PEG-100 stearate, glyceryl stearate-PEG-75 stearate, and tocopheryl acetate using an analytical balance. After weighing, add them to the emulsification pot. Accurately weigh deionized water, propylene glycol, cationic sodium hyaluronate, disodium EDTA, and dipotassium glycyrrhizate using an analytical balance. After weighing, add them to the aqueous phase mixing pot. Accurately weigh toluene-2,5-diamine sulfate and m-aminophenol using an analytical balance. After weighing, dissolve them in deionized water preheated to 40°C to prepare a pre-dissolved dye solution. A2: Place the aqueous phase mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 200 rpm. Stir for 20 minutes until completely dissolved to obtain a clear aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 100 rpm to melt all the oil phase raw materials into a uniform liquid. A3: Keep the emulsifying pot at 80°C. Slowly add the clear aqueous phase into the oil phase of the emulsifying pot in a thin stream. At the same time, increase the speed of the stirrer in the emulsifying pot to 800 rpm. After all the aqueous phase has been added, keep the temperature and speed constant and continue stirring and emulsifying for 15 minutes. After the stirring and emulsification are complete, turn on the homogenizer and homogenize at 5000 rpm for 3 minutes to obtain a fine primary paste. A4: Cool the primary paste to 50℃, adjust the stirring speed to 300rpm, and add water-soluble chitosan quaternary ammonium salt, hydrolyzed keratin peptide, sorghum red extract, aloe vera gel powder, henna quinone and mica in sequence. After adding each ingredient, continue stirring for 3 minutes to ensure uniform dispersion. Then add pre-dissolved dye solution, ethanolamine and aminomethylpropanol, and continue stirring for 10 minutes at the same speed. A5: After continuous stirring, cool down to 40℃, add fragrance, set the stirrer speed to 150rpm, stir for 5min, after stirring, transfer to a vacuum degassing tank, under a vacuum of -0.08MPa, stir slowly at 50rpm for 15min to remove the air bubbles trapped in the paste. A6: After degassing, use a filling machine to dispense the product into pre-specified hair dye tubes, seal them, and place the filled product in a constant temperature environment of 25℃ for 48 hours to obtain the dye paste.

7. A hair dyeing method for hair styling according to claim 4, characterized in that, The method for preparing the oxidized emulsion includes the following steps: B1: Use an analytical balance to accurately weigh deionized water and add it to the preparation vessel as the aqueous phase. Store hydrogen peroxide in a special clean polyethylene container and place it separately in a ventilated and low-temperature place. Store phosphoric acid and salicylic acid in glass containers and separate them from hydrogen peroxide. B2: Add disodium hydrogen phosphate, disodium ethylenediaminetetraacetate, tetraacetylethylenediamine and salicylic acid to the main preparation vessel, start stirring and control the speed at 300 rpm, and at the same time start the water bath circulation system to heat the aqueous phase system to 35°C, and stir at a constant temperature until all raw materials are completely dissolved to obtain a clear and transparent basic aqueous phase. B3: Cool the base aqueous phase to 25°C, set the stirrer speed to 200 rpm, and stir continuously. While stirring continuously, slowly and evenly add polyquaternium-67. After the addition is complete, increase the stirring speed to 500 rpm and stir continuously for 40 minutes to obtain the premixed solution. B4: While keeping the mixture stirred, add trehalose and panthenol to the premix in sequence. Stir for 5 minutes after each ingredient is added until completely dissolved. Then, slowly add 85% of the formulated amount of phosphoric acid using a dropping funnel to initially adjust the pH value to the range of 3.0-3.

5. B5: After pH adjustment, turn on the circulating water bath of the preparation vessel and adjust the temperature to 15℃. Then set the stirrer speed to 100rpm and continue to stir at low speed. Under low speed stirring, use a hydrogen peroxide-specific feed pump to slowly and steadily add hydrogen peroxide that has been pre-cooled to 8℃ into the preparation vessel. The total time for adding hydrogen peroxide is 30min. B6: After the hydrogen peroxide is added, the remaining phosphoric acid is added to the preparation vessel and then transferred to an empty homogenizer. Under a vacuum of -0.07 MPa, the mixture is homogenized at 2500 rpm for 5 minutes. After homogenization, the mixture is filtered through a 1 μm filter sieve. After filtration, the mixture is immediately filled into light-proof and pressure-resistant packaging bottles, sealed with nitrogen, and then placed in a cool environment at 20°C for 24 hours to stabilize, thus obtaining the oxidized emulsion.

8. A hair dyeing method for hair styling according to claim 5, characterized in that, The preparation method of the color-locking conditioner includes the following steps: C1: Accurately weigh cetearyl alcohol, diaminopropyl polydimethylsiloxane, sunflower seed oil, and tocopheryl acetate using an analytical balance and place them in an emulsifying pot. Accurately weigh deionized water, hydrolyzed soy protein, polyquaternium-10, dipotassium glycyrrhizate, ceramide NP, ubiquinone, and citric acid using an analytical balance and place them in a mixing pot. Accurately weigh phenoxyethanol-chlorophenoxyethanol and flavoring using an analytical balance and set aside. C2: Place the mixing pot in a water bath and heat it to 75°C. Turn on the stirring and set the speed to 300 rpm. Stir until all water-soluble components are completely dissolved to obtain a homogeneous aqueous phase. At the same time, heat the emulsification pot to 80°C and turn on the stirring and set the speed to 150 rpm to melt all oil phase raw materials into a transparent and uniform oil phase liquid. C3: Under the condition of maintaining 80℃, the homogeneous aqueous phase is slowly added to the oil phase in the emulsification pot in a thin stream. At the same time, the speed of the stirrer in the emulsification pot is increased to 1000 rpm. After all the aqueous phase is added, the temperature and speed are kept constant, and the emulsification is continuously stirred for 15 minutes. After the emulsification is completed, the homogenizer is turned on and the homogenizer is homogenized at 4000 rpm for 2 minutes to obtain a fine primary emulsion. C4: Cool the primary emulsion to 50°C, set the stirring speed to 250 rpm, add phenoxyethanol-chlorophenoxyethanol, stir for 5 min, after stirring, continue to cool to 40°C, add fragrance, set the stirrer speed to 150 rpm, stir and mix for 10 min, then transfer to a vacuum degassing tank, under a vacuum of -0.07 MPa, stir slowly at 50 rpm for 20 min to degas, to obtain a degassed emulsion; C5: The defoaming emulsion is dispensed into packaging bottles using a filling machine and sealed. Then, it is placed in a constant temperature environment below 25°C and allowed to stand for 72 hours to mature, resulting in a color-locking hair conditioner.

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