Processing method of knitted fabric

Abstract

The invention provides a knitted fabric treatment method, and belongs to the technical field of textile treatment. The method comprises the following steps of: soaking the knitted fabric in a pretreatment solution at the temperature of 50-60 DEG C for 30-60 minutes under the condition that the bath ratio is controlled to be 1: 20-30, placing the pretreated knitted fabric in a dyeing solution at the bath ratio of 1: 20-30, the concentration of a vegetable dye in the dyeing solution is 5-10% owf, the dyeing temperature is 50-60 DEG C and the dyeing time is 60-90 minutes, and finishing dip dyeing, wherein the concentration of a modifier in the pretreatment solution is 5-10% owf, the concentration of the vegetable dye in the dyeing solution is 5-10% owf, the dyeing temperature is 50-60 DEG C and the dyeing time is 60-90 minutes. Green dyeing with high dyeing rate and good color fastness of the knitted fabric is realized.

Description

Technical Field

[0001] The present application relates to a method for processing knitted fabrics, and belongs to the technical field of textile processing. Background Art

[0002] Plant dyes are extracted from plants and have the advantages of being green, harmless and renewable. With the development of science and technology and economy, green, healthy and ecological have become popular. Synthetic dyes produce a lot of harmful substances during production and application, which harm the human body and the natural environment. More and more people are turning their attention to plant dyes. At present, plant dyes are widely used in textiles made of natural fibers such as silk and cotton, and are favored by the market.

[0003] For a long time, plant dyeing requires the addition of metal ion mordants such as potassium aluminum sulfate, ferrous sulfate, and copper sulfate, which use the complexation of metal ions to improve the color yield and color fastness of plant dyes on fabrics. Since the mordants added in plant dyeing contain iron ions and copper ions that are harmful to the human body and the environment, they have also been questioned by the market. Therefore, how to improve the dyeing performance of plant dyes on natural fiber textiles and more environmentally friendly dyeing methods have become the focus of research.

[0004] To solve the above problems, one is to modify the structure of plant dyes, introduce water-soluble groups or cationic groups on the basis of the original structure to enhance the water solubility of dyes and the reactivity to fibers; the other is to modify natural fiber textiles, introduce cationic groups into natural fiber textiles by dipping or padding to enhance the reactivity of plant dyes with fibers and improve dyeing performance. For example: CN 115418869A uses chitosan and metal ions to pretreat fabrics to improve the color depth and color fastness of plant dye-dyed fabrics, and give textiles excellent antibacterial properties. CN115434166A uses low-temperature plasma technology to graft 2-methacryloyloxyethyl choline to the surface of fabrics, so that the fabrics have amphoteric charges, which improves the dye uptake and color fastness of the dyes. CN 115404705A uses natural polyphenol / polyamine modified liquid to treat fabrics, increase the dyeing binding sites of fabrics, and improve the binding fastness of plant dyes to fabrics. CN117005216A utilizes ultraviolet light grafting technology to graft hydrophilic monomers and lithospermum dye onto cotton fabrics, thereby achieving natural dyeing of fabrics at room temperature and improving the dyeing fastness of cotton fabrics.

[0005] The above patent documents introduce cationic groups into fabrics to make the fabrics have a stronger affinity for plant dyes, thereby improving the dyeing depth and color fastness of plant dyed fabrics. However, a common problem is that plant dyes are dyed too quickly, which easily causes uneven dyeing and local color spots. Summary of the invention

[0006] In view of this, the present application provides a method for processing knitted fabrics.

[0007] Specifically, the present application is implemented through the following scheme:

[0008] A method for processing knitted fabrics, characterized in that the steps are as follows:

[0009] Step 1, pretreatment: controlling the bath ratio to be 1:20-30, immersing the knitted fabric in the pretreatment solution, wherein the concentration of the modifier in the pretreatment solution is 5-10% owf, the pretreatment temperature is 50-60° C., and the pretreatment time is 30-60 min;

[0010] The modifier comprises the following components in the following mass ratios: 20 to 40 parts of chitosan derivative, 5 to 10 parts of pH regulator, 10 to 20 parts of inorganic metal ion compound, and 30 to 65 parts of deionized water.

[0011] Step 2, dyeing: placing the knitted fabric treated in step 1 in a dyeing solution, with a bath ratio of 1:20-30, a plant dye concentration of 5-10% owf in the dyeing solution, a dyeing temperature of 50-60°C, and a dyeing time of 60-90 minutes to complete the immersion dyeing.

[0012] The plant dye comprises 70-80 parts of dye components, 5-10 parts of biomass active components and 5-10 parts of biomass dispersing components.

[0013] The present invention starts from three perspectives: plant dyes, fabric pretreatment modification, and dyeing, and the three work synergistically to improve the dyeing rate and color fastness of plant dyes on knitted fabrics.

[0014] Further, as a preference:

[0015] The chitosan derivative is a mixture of one or more of carboxymethyl chitosan, hydroxyethyl chitosan and quaternary ammonium salt chitosan. The plant dye is adsorbed onto the fiber and combined with the fiber by relying on the positive charge groups carried on the chitosan molecules.

[0016] The pH regulator is a mixture of one or more of ammonium sulfate, citric acid, malic acid, and acetic acid, which maintains the solution in a stable acid-base environment and prevents the dye molecules from changing color.

[0017] The inorganic metal ion compound is a mixture of one or more of potassium aluminum sulfate, copper sulfate and ferrous sulfate, etc., and relies on the complexation of metal ions to tightly combine the plant dye molecules and the cellulose fiber molecules.

[0018] The preparation method of the modifier is as follows: adding a chitosan derivative to deionized water at 40-50° C. and stirring evenly to obtain a chitosan derivative solution; adding a pH regulator to the chitosan derivative solution and stirring evenly, and then adding an inorganic metal ion compound and stirring evenly to obtain the modifier.

[0019] The dye component is a mixture of one or more of hematoxylin dye, black tea dye, Millettia spatholobi dye, madder dye, pomegranate peel dye and onion peel dye. The dye components are powders extracted from hematoxylin, black tea, Millettia spatholobi, madder, pomegranate peel and onion peel. More preferably, the preparation method of the dye component is as follows:

[0020] The first step is to grind one or more of the following: sappan wood, black tea, Millettia spatholobi, madder, pomegranate peel, and onion peel to obtain a particle size of 1 to 2 cm, and put the particles into a 150 to 200 mesh extraction bag for later use;

[0021] In the second step, the raw material is put into a steam heating extraction tank at a material-liquid ratio of 5-20 g / mL, the temperature is raised to 95-100°C, the temperature is kept for 60-120 minutes, and the raw material is filtered through a plate and frame filter press into a liquid storage tank, and the process is repeated three times;

[0022] The third step is to pass the filtrate obtained in the second step into a vacuum concentration device, with the internal pressure set at -0.1 to -0.08 MPa, hot water circulated at 55 to 65°C, and vacuum concentrated for 12 to 24 hours. The specific gravity of the concentrated solution obtained is 1.1 to 1.2.

[0023] The fourth step is to pass the concentrated liquid obtained in the third step into a spray drying device, set the negative pressure to 0.5-1.0 KPa, the inlet air temperature to 140-150°C, the outlet air temperature to 90-100°C, and perform vacuum spray drying to obtain a solid powder of the dye component.

[0024] The biomass active ingredient is a mixture of one or more of casein, fibroin, gelatin, collagen, etc. When the above protein substances are mixed with plant dyes, the presence of the biomass active ingredient can provide groups such as carboxyl and amino groups, thereby improving the affinity with cellulose fibers.

[0025] The biomass dispersing component is a mixture of one or more of lignin, sodium lignin sulfonate and tannin, so as to enhance the dispersibility of the plant dye in the solution.

[0026] The preparation steps of the above-mentioned plant dye are as follows:

[0027] Step 1: put one or more of the above dye components into a multifunctional mixer and mix for 10 to 30 minutes.

[0028] Step 2: Add one or more of the above biomass active ingredients into step 1 and continue mixing for 10 to 30 minutes.

[0029] Step 3: Add one or more of the above biomass dispersion components into step 2, continue mixing for 10 to 30 minutes, and take out to obtain the plant dye.

[0030] Compared with the prior art, the present invention has the following technical effects:

[0031] First, the present invention provides a method for preparing green and environmentally friendly plant dyes, which fully blends the plant dyes with biomass additives (including biomass active ingredients and biomass dispersing ingredients), and utilizes the affinity of the biomass additives with the plant dyes and natural fibers to improve the dyeing properties of natural fiber fabrics.

[0032] Secondly, the present invention provides a method for preparing a natural fiber pretreatment modifier. The prepared metal ion-chitosan solution fully exerts the complexing effect of metal ions and the adsorption effect of chitosan to improve the bonding strength between plant dyes and natural fibers.

[0033] Third, the present invention provides a process for dyeing cellulose fiber knitted fabrics with plant dyes, thereby improving the dyeing performance of plant dyes on knitted fabrics. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clearer, the technical solutions of this application will be further described in detail below in combination with the specific cases in the embodiments of this application. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit the technical solutions of this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0035] The index test in the following embodiment:

[0036] The dyed cotton knitted fabrics were tested and rated for color fastness to perspiration, water and rubbing according to the national standard GB / T31702-2015. The dyeing depth K / S value was tested with a Datacolor-400 colorimeter, and the measurement was performed 4 times to take the average value.

[0037] Example 1

[0038] This embodiment takes cotton knitted fabric as the processing object, and the processing process is as follows:

[0039] Step 1, preparation of plant dyes:

[0040] (1) Millettia spatholobi, black tea, and pomegranate peel are taken and crushed in a mass ratio of 1:1:2, and the particle size is about 2 cm, and the particles are put into a 200-mesh extraction bag for standby use; at a material-liquid ratio of 20 g / mL, the extraction bag containing the crushed Millettia spatholobi, black tea, and pomegranate peel is put into a steam-heated extraction tank, the temperature is raised to 100° C., the temperature is kept for 100 min, and the extraction bag is filtered into a liquid storage tank through a plate-and-frame filter press, and the process is repeated three times; the obtained filtrate is passed into a vacuum concentration device, the internal air pressure is set to about -0.08 MPa, 60° C. hot water is circulated, and the vacuum concentration is performed for 24 hours, and the specific gravity of the obtained concentrated solution is about 1.2; the concentrated solution is passed into a spray drying device, the negative pressure is set to 1.0 KPa, the inlet air temperature is 140° C., and the outlet air temperature is 90° C., and vacuum spray drying is performed to obtain a solid powder, which is used as a dye component;

[0041] (2) 80 parts by weight of the dye component obtained in step (1) is put into a multifunctional mixer and mixed for 30 minutes, a total of 10 parts by weight of biomass active ingredients silk fibroin / gelatin egg (wherein the added mass ratio of silk fibroin to gelatin is 1:3) is added, and mixing is continued for 30 minutes, 10 parts by weight of biomass dispersing ingredient lignin is added, and mixing is continued for 30 minutes, and the mixture is taken out and placed in a sealed bag. This is the plant dye.

[0042] Step 2, prepare the modifier: accurately weigh 20 parts by mass of quaternary ammonium salt chitosan, add 50°C deionized water, stir evenly, then add 10 parts by mass of ammonium sulfate and stir evenly, finally add 20 parts by mass of potassium aluminum sulfate and stir evenly, and the modifier is prepared.

[0043] Step 3, pretreatment: pretreatment of the cotton knitted fabric with an overflow dyeing machine, a bath ratio of 1:20, an amount of the modifier in the pretreatment solution of 10% owf, a pretreatment temperature of 50° C., and a pretreatment time of 40 min.

[0044] Step 4, dyeing: dyeing is also carried out in an overflow dyeing machine, with a bath ratio of 1:20, a plant dye dosage of 10% owf, a dyeing temperature of 50°C, and a dyeing time of 90 minutes.

[0045] Comparative Example 1

[0046] This comparative example uses cotton knitted fabric as the processing object, and the processing process is as follows:

[0047] Step 1, preparing plant dye: taking Millettia spatholobi, black tea, and pomegranate peel in a mass ratio of 1:1:2 and crushing them to a particle size of about 2 cm, and putting them into a 200-mesh extraction bag for standby use; at a material-liquid ratio of 20 g / mL, putting the extraction bag containing the crushed materials of Millettia spatholobi, black tea, and pomegranate peel into a steam-heated extraction tank, heating it to 100°C, keeping it warm for 100 minutes, filtering it through a plate and frame filter press to a liquid storage tank, and repeating it three times; passing the obtained filtrate into a vacuum concentration device, setting the internal air pressure to about -0.08MPa, circulating hot water at 60°C, and vacuum concentrating for 24 hours, and the specific gravity of the obtained concentrated solution is about 1.2; passing the concentrated solution into a spray drying device, setting the negative pressure to 1.0KPa, the inlet air temperature to 140°C, and the outlet air temperature to 90°C, and performing vacuum spray drying to obtain a solid powder, which is used as a plant dye.

[0048] Step 2, dyeing: putting the cotton knitted fabric into an overflow dyeing machine for dyeing, with a bath ratio of 1:20, an amount of plant dye of 10% owf, a dyeing temperature of 50° C., and a dyeing time of 90 min.

[0049] The main difference between this comparative example and Example 1 is that the plant dye used does not contain biomass modified components and biomass dispersed components, and the cotton knitted fabric is not pretreated with a pretreatment modifier.

[0050] Table 1: Effects of different processes on the dyeing properties of cotton knitted fabrics

[0051]

[0052] As can be seen from Table 1, the K / S value of the dyed knitted fabric of Example 1 is much higher than that of Comparative Example 1, and the acid sweat resistance and alkali sweat resistance in the color fastness are 0.5 levels higher, indicating that the biomass modified components and biomass dispersed components in the dye composition and the pretreatment of the knitted fabric can effectively improve the color yield and color fastness of the dyed knitted fabric.

[0053] Comparative Example 2

[0054] This comparative example uses cotton knitted fabric as the processing object, and the processing process is as follows:

[0055] Step 1, dye preparation: The preparation process of plant dye is the same as that of Example 1.

[0056] Step 2, pretreatment: immerse the cotton knitted fabric in a 50wt.% composite aqueous solution of 2-methacryloyloxyethyl phosphorylcholine and 3-methacryloyldopamine for 5 minutes, the mass ratio of the two being 5:1, and then take it out and dry it.

[0057] Step 3, dyeing: putting the cotton knitted fabric into an overflow dyeing machine for dyeing, with a bath ratio of 1:20, an amount of plant dye of 10% owf, a dyeing temperature of 50° C., and a dyeing time of 90 min.

[0058] The difference between this comparative example and Example 1 is that the plant dye used does not contain biomass modified components and biomass dispersed components, and the cotton knitted fabric is pretreated with a composite aqueous solution of 2-methacryloyloxyethyl phosphorylcholine and 3-methacryloyldopamine.

[0059] Table 2: Effects of different pretreatment processes on the dyeing properties of cotton knitted fabrics

[0060]

[0061] It can be seen from the data in Table 2 that the K / S value of the dyed knitted fabric of Example 1 is not much different from the K / S value of Comparative Example 2, but the color fastness to perspiration and the color fastness to dry friction of Example 1 are better than those of Comparative Example 2, indicating that the pretreatment agent used in this embodiment is better than that of Comparative Example 2, and the pretreatment agent used in Comparative Example 2 is a chemical reagent, which is harmful to the human body and the environment, and does not conform to the concept of green development.

[0062] Example 2

[0063] This embodiment is the same as the embodiment 1, except that: in the preparation process of the plant dye, the biomass active ingredients are replaced by casein, fibroin, collagen, gelatin, casein / fibroin (the mass ratio of casein to fibroin is 1:1), casein / gelatin (the mass ratio of casein to gelatin is 1:3), casein / collagen (the mass ratio of casein to collagen is 1:2), fibroin / collagen (the mass ratio of fibroin to collagen is 1:2), collagen / gelatin (the mass ratio of collagen to gelatin is 1:3) to replace the fibroin / gelatin in embodiment 1. The fabrics obtained by the treatment are recorded as group 3-1, group 3-2, group 3-3, group 3-4, group 3-5, group 3-6, group 3-7, group 3-8, and group 3-9.

[0064] Table 3: Effects of plant dyes with different biomass active ingredients on dyeing properties

[0065]

[0066] As can be seen from the data in Table 3, the plant dyes (3-4 groups) made from single-component gelatin protein have better dyeing K / S values ​​and color fastness than the plant dyes (3-1 groups, 3-2 groups, 3-3 groups) that also contain single-component biomass active ingredients. The plant dyes (Example 1, 3-4 groups, 3-6 groups, 3-9 groups) made from two components (containing gelatin protein) have better dyeing K / S values ​​and color fastness than the plant dyes (3-5 groups, 3-7 groups, 3-8 groups) made from the same two components, and the two components are better than the single component. It can be seen that the adsorption capacity of gelatin protein is stronger than other protein compounds. Therefore, it can be seen from Comparative Example 1 and Table 3 that the biomass active ingredient is preferably gelatin protein / casein.

[0067] Example 3

[0068] This embodiment is similar to the embodiment 1 in configuration, except that in the preparation of the plant dye, the biomass dispersed components are replaced by sodium lignin sulfonate, tannin, lignin / tannin (mass ratio 2:1), sodium lignin sulfonate / tannin (mass ratio 2:1), respectively. The fabrics obtained by the treatment are recorded as group 4-1, group 4-2, group 4-3, and group 4-4, respectively.

[0069] Table 4: Effect of plant dyes with different biomass dispersion components on dyeing performance

[0070]

[0071] As shown in Table 4, the K / S value and color fastness of the plant dyes corresponding to the biomass dispersion components containing sodium lignin sulfonate (Group 4-1, Group 4-4) are better than those corresponding to the plant dyes of the biomass dispersion components not containing sodium lignin sulfonate (Example 1, Group 4-2, Group 4-3), because the dispersing effect of sodium lignin sulfonate on plant dyes is stronger than lignin and tannin. Therefore, the biomass dispersion component is preferably sodium lignin sulfonate / tannin.

[0072] Example 4

[0073] This embodiment has the same configuration as that of embodiment 1, except that during the preparation of the modifier, the quaternary ammonium salt chitosan is replaced by carboxymethyl chitosan, hydroxyethyl chitosan, carboxymethyl chitosan / quaternary ammonium salt chitosan (mass ratio 1:2), and hydroxyethyl chitosan / quaternary ammonium salt chitosan (mass ratio 1:1), respectively. The resulting fabrics are sequentially recorded as group 5-1, group 5-2, group 5-3, and group 5-4.

[0074] Table 5: Effect of modifiers of different chitosan derivatives on dyeing properties

[0075]

[0076]

[0077] As can be seen from the data in Table 5, the modifiers containing quaternary ammonium chitosan (Example 1), carboxymethyl chitosan / quaternary ammonium chitosan (Group 5-3), and hydroxyethyl chitosan / quaternary ammonium chitosan (Group 5-4) have better dyeing K / S values ​​and color fastness for dyed cotton knitted fabrics than those containing carboxymethyl chitosan (Group 5-1) and hydroxyethyl chitosan (Group 5-2). This is because the positively charged groups contained in quaternary ammonium chitosan have a strong affinity for plant dyes. Therefore, quaternary ammonium chitosan / hydroxyethyl chitosan is preferred as the chitosan derivative.

[0078] Example 5

[0079] The configuration of this embodiment is the same as that of embodiment 1, except that in the preparation of the modifier, citric acid, malic acid, and acetic acid are used to replace the ammonium sulfate in embodiment 1. The treated fabrics are recorded as group 6-1, group 6-2, and group 6-3, respectively.

[0080] Table 6: Effect of different pH modifiers on dyeing performance

[0081]

[0082] As shown in Table 6, compared with Example 1, the K / S value of cotton knitted fabric dyeing in Group 6-1 and Group 6-3 was not significantly improved, and the color fastness was improved to a certain extent. Among them, when malic acid was used as the pH regulator in Group 6-2, the dyeing K / S value and color fastness of the dyed cotton knitted fabric were better than those in other examples, so malic acid was pre-selected as the pH regulator.

[0083] Example 6

[0084] This embodiment is similar to the embodiment 1 in configuration, except that: in the preparation of the modifier, potassium aluminum sulfate is replaced by copper sulfate, ferrous sulfate, potassium aluminum sulfate / copper sulfate, potassium aluminum sulfate / ferrous sulfate, potassium aluminum sulfate / copper sulfate / ferrous sulfate. The fabrics obtained by the treatment are recorded as group 7-1, group 7-2, group 7-3, group 7-4, and group 7-5.

[0085] Table 7: Effect of modifiers of different inorganic metal ion compounds on dyeing properties

[0086]

[0087]

[0088] As shown in Table 7, the dyeing K / S value of cotton knitted fabrics treated with the modifiers corresponding to Groups 7-5, 7-4 and 7-2 is better than that of Example 1 and Groups 7-1 and 7-3. Compared with potassium aluminum sulfate and copper sulfate, ferrous sulfate has a more obvious color improvement on cotton knitted fabrics. On the contrary, the color fastness of cotton knitted fabrics treated with Groups 7-1, 7-2, 7-4 and 7-5 is higher than that of Groups 7-1, 7-2, 7-4 and 7-5. Therefore, the inorganic metal ion compound is preferably potassium aluminum sulfate.

[0089] The above-mentioned embodiments only express several feasible implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention, and the embodiments are not used to limit the scope of protection in the claims of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and all equivalent implementations or changes that do not depart from the present invention should be included in the technology of the present invention.

Claims

1. A method for processing a knitted fabric, characterized in that: Here are the steps: Step 1, pretreatment: control the bath ratio to 1:20-30, immerse the knitted fabric in the pretreatment solution, the modifier concentration in the pretreatment solution is 5-10% owf, the pretreatment temperature is 50-60°C, and the pretreatment time is 30-60 minutes; The modifier comprises the following components in the following mass ratios: 20 to 40 parts of chitosan derivative, 5 to 10 parts of pH regulator, 10 to 20 parts of inorganic metal ion compound, and 30 to 65 parts of deionized water. Step 2, dyeing: place the knitted fabric treated in step 1 in the dye solution, the bath ratio is 1:20-30, the concentration of the plant dye in the dye solution is 5-10% owf, the dyeing temperature is 50-60°C, and the dyeing time is 60-90 minutes to complete the immersion dyeing. The plant dye comprises 70-80 parts of dye components, 5-10 parts of biomass active components and 5-10 parts of biomass dispersing components.

2. The method for dyeing a knitted fabric according to claim 1, characterized in that: The chitosan derivative is a mixture of one or more of carboxymethyl chitosan, hydroxyethyl chitosan and quaternary ammonium salt chitosan.

3. The method for processing a knitted fabric according to claim 1, characterized in that: The pH regulator is a mixture of one or more of ammonium sulfate, citric acid, malic acid and acetic acid.

4. The method for processing a knitted fabric according to claim 1, characterized in that: The inorganic metal ion compound is a mixture of one or more of potassium aluminum sulfate, copper sulfate and ferrous sulfate.

5. A method for processing knitted fabrics according to claim 1, characterized in that: The preparation method of the modifier is as follows: adding a chitosan derivative to deionized water at 40-50° C. and stirring evenly to obtain a chitosan derivative solution; adding a pH regulator to the chitosan derivative solution and stirring evenly, and then adding an inorganic metal ion compound and stirring evenly to obtain the modifier.

6. The method for processing a knitted fabric according to claim 1, characterized in that: The dye component is a mixture of one or more of hematoxylin dye, black tea dye, millettia spatholobi dye, madder dye, pomegranate peel dye and onion peel dye.

7. A method for processing knitted fabrics according to claim 6, characterized in that: The dye composition is prepared as follows: The first step is to grind one or more of the following: sappan wood, black tea, Millettia spatholobi, madder, pomegranate peel, and onion peel to obtain a particle size of 1 to 2 cm, and put the particles into a 150 to 200 mesh extraction bag for later use; The second step is to put the raw materials into a steam heating extraction tank at a material-liquid ratio of 5-20 g / mL, raise the temperature to 95-100°C, keep the temperature for 60-120 minutes, and filter; The third step is to pass the filtrate obtained in the second step into a vacuum concentration device, with the internal pressure set at -0.1 to -0.08 MPa, hot water circulated at 55 to 65°C, and vacuum concentrated for 12 to 24 hours. The specific gravity of the concentrated solution obtained is 1.1 to 1.

2. The fourth step is to pass the concentrated liquid obtained in the third step into a spray drying device, set the negative pressure to 0.5-1.0 KPa, the inlet air temperature to 140-150°C, the outlet air temperature to 90-100°C, and perform vacuum spray drying to obtain a solid powder of the dye component.

8. The method for processing a knitted fabric according to claim 1, characterized in that: The biomass active ingredient is one or more mixtures of casein, silk fibroin, gelatin, collagen and the like.

9. A method for processing knitted fabrics according to claim 1, characterized in that: The biomass dispersion component is a mixture of one or more of lignin, sodium lignin sulfonate and tannin.

10. A method for processing knitted fabrics according to any one of claims 1 to 9, characterized in that: The knitted fabric is a cellulose fiber knitted fabric.

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