Polylactic acid wool blending material dyeing method based on composite carrier technology

Abstract

The invention provides a polylactic acid wool blending material dyeing method based on a composite carrier technology, and the method comprises the following steps: S1, adding 2-5g / L of a refining agent under the condition that the bath ratio is 1: 15-1: 20, and treating for 10-20 minutes; s2, in a first bath, under the condition that the pH is 5.0-5.5 and is weakly acidic to be neutral, the temperature is increased to 92-98 DEG C, heat preservation is conducted for 40-60 min, in the presence of the composite dyeing carrier, disperse dye is adopted for dyeing the polylactic acid fiber component, and the using amount of the disperse dye is 5.0%-8.0% of the weight of the fabric; s3, performing reduction cleaning on the material dyed in the step S2; s4, in the second bath, under the acidic condition that the pH is 4.5-5, the temperature is increased to 85-90 DEG C, heat preservation is conducted for 40-60 min, and the wool component is dyed. According to the invention, excellent color fastness and color uniformity of the polylactic acid wool blended material after dyeing are ensured.

Description

Technical Field

[0001] This invention relates to a dyeing method for wool blended materials, specifically a dyeing method for polylactic acid wool blended materials based on composite carrier technology, belonging to the field of textile dyeing and finishing technology. Background Technology

[0002] Polylactic acid (PLA), a biodegradable fiber derived from renewable plant resources, is hailed as one of the most promising eco-fibers due to its excellent drape, luster, and skin comfort. Wool, on the other hand, is highly favored for its unique warmth, elasticity, and superior hand feel. Blending PLA and wool can combine the excellent properties of both fibers to develop new fabrics that are eco-friendly, comfortable, and have a high-end feel, aligning with the current trend of green and sustainable development in the textile market. However, significant differences in physical structure and chemical properties between PLA and wool pose a serious challenge to the dyeing of blended materials, especially dark-colored dyeing.

[0003] PLA fiber is a thermoplastic polyester fiber with a low glass transition temperature (Tg), approximately 55-65℃. The ester bonds in its molecular structure are easily hydrolyzed under high temperatures and acidic or alkaline conditions, leading to a decrease in the degree of polymerization and a severe loss of fiber strength. Due to its hydrophobicity and high crystallinity, dyes have difficulty penetrating it, and traditional processes typically require the use of disperse dyes under neutral conditions above 110℃. In contrast, wool is a protein fiber with a scaly surface structure. Traditional dyeing requires acidic conditions (pH 3-4) close to its boiling point (98-105℃), where the acid and high temperature cause the scaly layer to swell, facilitating the application of acid dyes or reactive wool dyes.

[0004] In existing dyeing techniques, the traditional two-bath method typically involves dyeing wool first and then PLA. After the first bath of wool dyeing, even after washing, acidic substances remain inside and on the surface of the fibers. When the fibers enter the second bath of PLA in a neutral dyeing environment at temperatures above 110°C, these residual acids act as catalysts, rapidly accelerating the hydrolysis of the PLA fibers, leading to a significant decrease in strength and rendering them unsuitable for use. Simultaneously, the acidic dye residue from the first bath severely contaminates the PLA fibers in the high-temperature second bath, resulting in dull colors, inaccurate color reproduction, and poor colorfastness.

[0005] Conventional co-dyeing methods, in order to balance the dyeing of both fibers, can only adopt compromise process conditions. As a result, neither fiber often achieves its optimal dyeing effect. PLA dyes are too light due to insufficient temperature, while wool is difficult to dye deeply and thoroughly due to improper pH and insufficient temperature. Furthermore, the problem of dye cross-contamination is more prominent, making it impossible to meet the requirements of dark-colored products.

[0006] While existing technologies have attempted to use single carriers such as benzyl benzoate to lower PLA dyeing temperatures, the dyeing-promoting effect of this single-carrier approach is limited, especially when dyeing dark colors, requiring higher temperatures or longer dyeing times, and the protection of PLA fibers remains unsatisfactory. Furthermore, single carriers do not significantly improve dye staining and leveling properties, failing to systematically resolve the aforementioned problems.

[0007] Therefore, there is an urgent need in this field for a novel dyeing method that can fundamentally overcome the technical bottlenecks faced by polylactic acid wool blends when dyeing dark colors, such as insufficient color depth, severe fiber damage, and mutual staining. Summary of the Invention

[0008] Based on the above background, the purpose of this invention is to provide a dyeing method for polylactic acid wool blended materials based on composite carrier technology. By adopting a high-efficiency composite carrier system combined with a dyeing sequence of dispersion followed by acidity, the color yield of polylactic acid fibers is significantly improved while effectively controlling fiber damage, ensuring excellent color fastness and color uniformity.

[0009] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0010] A dyeing method for polylactic acid wool blended materials based on composite carrier technology, the method comprising the following steps:

[0011] S1. Pretreatment: Under the condition of a bath ratio of 1:15 to 1:20, add 2 to 5 g / L of refining agent and treat at 50 to 60°C for 10 to 20 minutes.

[0012] S2. First Bath Deep Dyeing of Polylactic Acid Components: In the first bath, under weakly acidic to neutral conditions (pH 5.0-5.5), the temperature is increased to 92-98°C at a rate of 1-2°C / min and held for 40-60 minutes. In the presence of a composite dyeing carrier, disperse dyes are used to dye the polylactic acid fiber components. The amount of disperse dye used is 5.0%-8.0% of the fabric weight.

[0013] S3. Reduction cleaning: Perform reduction cleaning on the material dyed in step S2;

[0014] S4. Second Bath Deep Dyeing of Wool Components: In the second bath, under acidic conditions of pH 4.5-5, the temperature is raised to 85-90℃ at a rate of 1-2℃ / min and held for 40-60min. Acid dyes or wool reactive dyes are used to dye the wool components. The amount of acid dyes or wool reactive dyes used is 2%-4% of the fabric weight.

[0015] The composite dyeing carrier significantly plasticizes and swells polylactic acid (PLA) fibers, effectively lowering their glass transition temperature and opening internal channels. This allows disperse dye molecules to overcome energy barriers and smoothly penetrate and fix into the fiber at a lower temperature (92-98℃). Simultaneously, a synergistic penetrant reduces the surface tension of the dye bath, accelerating dye diffusion and adsorption to the fiber surface, thus achieving dark-colored dyeing of PLA under non-high-temperature (<100℃) conditions. This low-temperature strategy avoids the PLA hydrolysis and strength reduction caused by traditional high-temperature (>110℃) processes. Furthermore, the specific process sequence of dyeing PLA first and then wool, combined with an intermediate reduction cleaning step, thoroughly removes the disperse dye adsorbed on the wool surface. The second bath wool dyeing is carried out at a gentler temperature of 85-90℃, ensuring the dye uptake of wool while further avoiding secondary damage to the dyed PLA fibers from the acidic environment, fundamentally solving the problems of difficult dark-colored dyeing and severe staining in blended materials.

[0016] Preferably, the composite staining carrier is composed of a main carrier and a synergistic penetrant. The main carrier is selected from one or more of benzoate esters, cinnamate esters, salicylate esters and their derivatives, and the synergistic penetrant is selected from one or more of fatty alcohol polyoxyethylene ethers, alkyl glycosides and their modified products.

[0017] Preferably, the main carrier is methyl cinnamate, benzyl benzoate, or methyl salicylate; and the synergistic penetrant is fatty alcohol polyoxyethylene ether or alkyl glycoside.

[0018] Preferably, in the composite staining carrier, the mass ratio of the main carrier to the synergistic penetrant is 2:1 to 4:1, and the total amount of the composite staining carrier is 2 to 6 g / L.

[0019] Preferably, in step S2, 1~2 g / L of leveling agent and 0.2~1 g / L of dispersant are also added.

[0020] Preferably, the reduction cleaning in step S3 uses 2-4 g / L sodium dithionite and 1-3 g / L sodium carbonate, and is treated at 70°C for 20-30 min.

[0021] Preferably, the pH value in both step S2 and step S4 is adjusted using an acetate-sodium acetate buffer system.

[0022] Preferably, in step S4, 1~2g / L of wool protectant is also added.

[0023] Preferably, in step S4, 2-3 g / L of wool leveling agent is also added.

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

[0025] The present invention discloses a dyeing method for polylactic acid wool blended materials based on composite carrier technology, which breaks through the limitation that polylactic acid must be dyed at a high temperature of >110℃. By controlling the dyeing temperature below 98℃, the hydrolysis and degradation of polylactic acid fibers are greatly reduced, resulting in a significant improvement in the tensile strength retention rate of the dyed fabric. In particular, the strength retention rate of the polylactic acid component can reach more than 90%, solving the problem of fabric brittleness in traditional processes.

[0026] This invention utilizes the plasticizing and dyeing-promoting effects of a composite carrier to enable disperse dyes to penetrate a large amount into polylactic acid fibers, even at lower temperatures. Experiments show that the K / S value of the fabric obtained by the method of this invention is significantly higher than that of the traditional process, and it can obtain dark-colored products with deep and rich colors.

[0027] This invention employs a unique two-bath process combined with intermediate reduction cleaning technology to thoroughly remove disperse dyes adhering to wool in the first bath. This not only ensures the purity of the final product's color but also significantly improves the fabric's wash fastness, rubbing fastness, and stain fastness, with all fastness indicators reaching level 4 or above. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0029] Figure 1 This is a schematic flowchart of a method for dyeing polylactic acid wool blended materials based on composite carrier technology according to the present invention.

[0030] Figure 2 This is a test report image from a third-party testing agency for the PLA / wool (50 / 50) blended yarn after dyeing, as described in Example 1 of this invention. Detailed Implementation

[0031] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings. It should be understood that the implementation of the present invention is not limited to the following embodiments, and any modifications and / or alterations made to the present invention will fall within the protection scope of the present invention.

[0032] In this invention, unless otherwise specified, all parts and percentages are by weight, and the equipment and raw materials used are commercially available or commonly used in the art. Unless otherwise specified, the methods in the following embodiments are conventional methods in the art. Unless otherwise specified, the components or equipment in the following embodiments are general standard parts or components known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0033] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In this detailed description, numerous specific details are set forth to facilitate explanation and provide a thorough understanding of the embodiments of the present invention. However, one or more embodiments may be practiced by those skilled in the art without these specific details.

[0034] like Figure 1 As shown, this invention provides a method for dyeing polylactic acid wool blended materials based on composite carrier technology, the method comprising the following steps:

[0035] S1. Pretreatment: Under the condition of a bath ratio of 1:15 to 1:20, add 2 to 5 g / L of refining agent and treat at 50 to 60°C for 10 to 20 minutes.

[0036] S2. First Bath Deep Dyeing of Polylactic Acid Components: In the first bath, under weakly acidic to neutral conditions (pH 5.0-5.5), the temperature is increased to 92-98°C at a rate of 1-2°C / min and held for 40-60 minutes. In the presence of a composite dyeing carrier, disperse dyes are used to dye the polylactic acid fiber components. The amount of disperse dye used is 5.0%-8.0% of the fabric weight.

[0037] S3. Reduction cleaning: Perform reduction cleaning on the material dyed in step S2;

[0038] S4. Second Bath Deep Dyeing of Wool Components: In the second bath, under acidic conditions of pH 4.5-5, the temperature is raised to 85-90℃ at a rate of 1-2℃ / min and held for 40-60min. Acid dyes or wool reactive dyes are used to dye the wool components. The amount of acid dyes or wool reactive dyes used is 2%-4% of the fabric weight.

[0039] This method, through the use of a highly efficient composite carrier system combined with a dyeing sequence of dispersion followed by acidity, significantly increases the color yield of PLA fibers while effectively controlling fiber damage, ensuring excellent color fastness and color uniformity. The composite carrier system of this invention is not a simple auxiliary agent, but is specially designed to achieve low-temperature deep dyeing and fiber protection. It is composed of an environmentally friendly main carrier and a biodegradable synergistic penetrant, constructing a synergistic mechanism of expansion-penetration-transportation.

[0040] Environmentally friendly host carriers refer to compounds that efficiently expand PLA fibers and reduce dyeing activation energy, while possessing low toxicity, low bioaccumulation, and can be effectively degraded in the natural environment through hydrolysis or microbial action. Compared to traditional chlorobenzene carriers, their toxicity is significantly reduced. In the environment, they can hydrolyze into benzoic acid and corresponding alcohols, and these decomposition products are more easily further biodegraded. PLA is a partially crystalline polymer; below its glass transition temperature, its molecular chain segments are frozen, making it difficult for dye molecules to diffuse in. The molecular structure of the host carrier has a certain degree of compatibility with the PLA macromolecular chain. At dyeing temperatures of 85–98°C, host carrier molecules can penetrate and embed themselves between PLA macromolecular chains. This behavior weakens the interaction forces between PLA macromolecular chains, increases the mobility of chain segments, thereby significantly increasing the free volume of the fiber and temporarily lowering the glass transition temperature. By expanding the fiber, the host carrier lowers the energy barrier required for disperse dyes to diffuse from the dye bath into the fiber interior. This allows the dye to gain sufficient kinetic energy and rapidly and extensively penetrate the fiber interior at temperatures lower than traditional PLA dyeing temperatures, thus achieving deep dyeing at low temperatures.

[0041] Biodegradable synergistic penetrants are surfactants that effectively reduce surface tension, promote the penetration of carriers and dyes into the fiber interior, and whose molecular structure conforms to internationally recognized biodegradable standards. Synergistic penetrants are highly efficient surfactants that significantly reduce the surface tension of the dye liquor. This allows the dye liquor to quickly and evenly wet and spread on the hydrophobic PLA fiber surface and rapidly penetrate into the interior of tightly packed yarns or fabrics. This ensures that the main carrier and dye can fully and evenly contact each fiber. Furthermore, synergistic penetrants form micelles in the dye liquor, providing a certain degree of solubilization and transport capacity for the hydrophobic main carrier and disperse dyes.

[0042] The synergistic effect of an environmentally friendly carrier and a biodegradable penetrant achieves low-temperature, deep-color, uniform, and low-damage dyeing. Using the carrier alone may result in uneven penetration and low efficiency, while using the penetrant alone fails to open the PLA fiber structure. The synergistic effect of both allows PLA fibers to achieve dyeing depths (K / S values) at temperatures as low as 92-98℃, even exceeding those of traditional 110℃ processes. Simultaneously, the significant temperature reduction effectively inhibits PLA hydrolysis, resulting in a substantial increase in fiber strength retention, reaching over 90%. Furthermore, for wool fibers, the low-temperature environment throughout the process reduces the risk of damage and felting.

[0043] Example 1

[0044] This embodiment provides a dyeing method for polylactic acid / wool blended materials based on composite carrier technology, specifically for dyeing PLA / wool (50 / 50) blended yarn to an extra-deep black. The specific steps of this method are as follows:

[0045] S1. Pretreatment: The PLA / wool (50 / 50) blended yarn is pretreated to remove surface oil and impurities. The bath ratio is 1:20, 3 g / L of refining agent is added, and the mixture is heated at 50℃ for 15 min. After the treatment, the blended yarn is rinsed with deionized water to remove residual solution.

[0046] S2, First Bath (PLA Dyeing): Bath ratio 1:15, composite carrier is methyl cinnamate 3.0 g / L and fatty alcohol polyoxyethylene ether (JFC) 1.0 g / L, pH value approximately 5.2, pH value adjusted with acetate-sodium acetate buffer system, disperse black dye dosage 7% (owf), leveling agent 1.5 g / L, dispersant 1 g / L. Process curve: dyeing at 40℃, heating to 98℃ at 1℃ / min, holding at 98℃ for 50 min, cooling to 50℃ at 1℃ / min, draining the bath.

[0047] S3. Enhanced reducing cleaning: 3 g / L sodium hydrosulfite, 1 g / L soda ash, 70℃, 20 min, followed by thorough hot water and cold water washing.

[0048] S4, Second Bath (Wool Dyeing): Bath ratio 1:15, pH 4.5, pH adjusted with acetic acid, weakly acidic black dye 4% (owf), wool leveling agent 2.0 g / L, wool protectant 1.5 g / L. Process curve: Dyeing at 40℃, heating to 90℃ at 1℃ / min, holding at 90℃ for 50 min, slowly cooling, and draining the liquor. Post-treatment: cold water washing, dehydration, and drying at 60℃.

[0049] The test report of the obtained sample is as follows Figure 2 As shown.

[0050] Example 2

[0051] This embodiment provides a dyeing method for polylactic acid / wool blended materials based on composite carrier technology, specifically for deep navy blue dyeing of PLA / wool (50 / 50) blended yarn. The specific steps of this method are as follows:

[0052] S1. Pretreatment: The PLA / wool (50 / 50) blended yarn is pretreated to remove surface oil and impurities. The liquor ratio is 1:20, 3g / L of refining agent is added, and the mixture is heated at 50℃ for 15 min. After the treatment, the blended material is rinsed with deionized water to remove residual solution.

[0053] S2, First Bath (PLA Dyeing): Bath ratio 1:20, composite carrier is benzyl benzoate 3.5 g / L and alkyl glycoside 1.5 g / L, pH value is 5.5, pH value is adjusted by acetate-sodium acetate buffer system, disperse navy blue dye amount is 7% (owf), process curve is: dyeing at 40℃, heating to 98℃ at 1℃ / min, holding at 98℃ for 45 min, cooling slowly, and draining the liquid.

[0054] S3. Enhanced reduction cleaning: conditions are the same as in Example 1.

[0055] S4, Second Bath (Wool Dyeing): Bath ratio 1:20, pH 4.2, pH adjusted with acetic acid, 4.0% (owf) of reactive navy blue dye for wool, 2.0 g / L of wool leveling agent, and 1.5 g / L of wool protecting agent. The process curve is as follows: dyeing at 40℃, increasing the temperature to 85℃ at a rate of 1℃ / min, holding at that temperature for 50 min, slowly cooling, and draining the liquor. Post-treatment involves cold water washing, dehydration, and drying at 60℃.

[0056] Comparative Example 1

[0057] This embodiment provides a traditional high-temperature two-bath dyeing method for polylactic acid (PLA) wool blended materials, which involves dyeing the wool first and then the PLA, using the same yarn and total amount of dye as in Example 1. The specific steps of this method are as follows:

[0058] S1. Pretreatment: The conditions are the same as in Example 1.

[0059] S2, First Bath (Wool Dyeing): pH=4.0, 98 ℃×60 min, then wash with water.

[0060] S3. Enhanced reduction cleaning: conditions are the same as in Example 1.

[0061] S4, Second Bath (PLA Staining): No carrier added, pH=6.0, 110℃×50 min, followed by routine reduction and washing.

[0062] Comparative Example 2

[0063] This embodiment provides a single-carrier, two-bath dyeing method for polylactic acid wool blended materials, using the same yarn and total dye amount as in Example 1. The specific steps of this method are as follows:

[0064] S1. Pretreatment: Conditions are the same as in Example 1.

[0065] S2, First Bath (Dyeing PLA): Only 3.0 g / L methyl cinnamate was used, with no biodegradable synergistic penetrant JFC. Other process parameters were exactly the same as in Example 1.

[0066] S3. Enhanced reduction cleaning: conditions are the same as in Example 1.

[0067] S4, Second Bath (Wool Dyeing): Exactly the same as in Example 1.

[0068] Comparative Example 3

[0069] This embodiment provides a low-temperature two-bath dyeing method for polylactic acid wool blended materials without adding a carrier, using the same amount of yarn and dye as in Example 1. The specific steps of this method are as follows:

[0070] S1. Pretreatment: Conditions are the same as in Example 1.

[0071] S2, First Bath (Dyeing PLA): No carrier is added, and other process parameters are the same as in Example 1.

[0072] S3. Enhanced reduction cleaning: conditions are the same as in Example 1.

[0073] S4, Second Bath (Wool Dyeing): Exactly the same as in Example 1.

[0074] The samples prepared in Examples 1-2 and Comparative Examples 1-3 were subjected to standard tests, and the test results are shown in Table 1.

[0075] Standard test results of Examples 1-2 and Comparative Examples 1-3

[0076]

[0077] As shown in Table 1, Examples 1-2 exhibit greater advantages in color depth compared to Comparative Example 1, with significant improvements in fiber strength retention and color fastness. This demonstrates that the pre-dyeing process sequence of PLA and the composite carrier technology solve the problems of PLA hydrolysis and dye staining caused by residual acid in traditional methods. The significantly higher K / S values ​​of Examples 1-2 compared to Comparative Example 2 demonstrate the crucial role of the synergistic penetrant in the composite carrier. Through synergy with the main carrier, it enhances dye penetration and dyeing efficiency, achieving a deep dyeing effect unattainable by a single carrier. In Comparative Example 3, without a carrier, the K / S value is significantly lower, and the PLA fibers are almost impossible to dye deeply at 95°C, which conversely proves the effectiveness of the composite carrier system of this invention.

[0078] In summary, the present invention provides a dyeing method for polylactic acid wool blended materials based on composite carrier technology, which successfully achieves deep dyeing of polylactic acid wool blended materials and obtains excellent color fastness while ensuring low fiber damage.

[0079] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for dyeing polylactic acid wool blended materials based on composite carrier technology, characterized in that: The method includes the following steps: S1. Pretreatment: Under the condition of a bath ratio of 1:15 to 1:20, add 2 to 5 g / L of refining agent and treat at 50 to 60°C for 10 to 20 minutes. S2. First Bath Deep Dyeing of Polylactic Acid Components: In the first bath, under weakly acidic to neutral conditions (pH 5.0-5.5), the temperature is increased to 92-98°C at a rate of 1-2°C / min and held for 40-60 minutes. In the presence of a composite dyeing carrier, disperse dyes are used to dye the polylactic acid fiber components. The amount of disperse dye used is 5.0%-8.0% of the fabric weight. S3. Reduction cleaning: Perform reduction cleaning on the material dyed in step S2; S4. Second Bath Deep Dyeing of Wool Components: In the second bath, under acidic conditions of pH 4.5-5, the temperature is raised to 85-90℃ at a rate of 1-2℃ / min and held for 40-60min. Acid dyes or wool reactive dyes are used to dye the wool components. The amount of acid dyes or wool reactive dyes used is 2%-4% of the fabric weight.

2. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: The composite staining carrier is composed of a main carrier and a synergistic penetrant. The main carrier is selected from one or more of benzoic acid esters, cinnamic acid esters, salicylic acid esters and their derivatives. The synergistic penetrant is selected from one or more of fatty alcohol polyoxyethylene ethers, alkyl glycosides and their modified products.

3. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 2, characterized in that: The main carrier is methyl cinnamate, benzyl benzoate, or methyl salicylate; the synergistic penetrant is fatty alcohol polyoxyethylene ether or alkyl glycoside.

4. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 2, characterized in that: In the composite staining carrier, the mass ratio of the main carrier to the synergistic penetrant is 2:1 to 4:1, and the total amount of the composite staining carrier is 2 to 6 g / L.

5. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: In step S2, 1~2 g / L of leveling agent and 0.2~1 g / L of dispersant are also added.

6. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: The reduction cleaning in step S3 uses 2-4 g / L sodium dithionite and 1-3 g / L sodium carbonate, and is treated at 70°C for 20-30 min.

7. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: The pH value in both steps S2 and S4 is adjusted using an acetate-sodium acetate buffer system.

8. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: In step S4, 1~2g / L of wool protectant is also added.

9. The dyeing method for polylactic acid wool blended materials based on composite carrier technology according to claim 1, characterized in that: In step S4, 2-3 g / L of wool leveling agent is also added.

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