Textile natural dyeing and composite tie-dyeing and fixing method based on ningxia red wolfberry original pulp

Abstract

This invention belongs to the field of natural plant dyeing technology for textiles, and discloses a method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp. This method uses cold-pressed pulp from fresh Ningxia red goji berries as the core dye. The dyeing process involves core steps including goji berry pulp extraction, fabric modification pretreatment, goji berry pulp dye liquor preparation, constant temperature dyeing, composite mordant color fixing, and color-locking and setting. Fabric pre-modification is achieved through a compound of alum and chitosan, combined with a formaldehyde-free cationic fixing agent to construct a composite mordant system. Low-temperature dyeing and baking setting processes are then used to create a three-dimensional cross-linked structure of dye, fiber, and mordant. This method is entirely free of harmful chemical reagents, improving dye uptake and color fastness. The finished product has a rich color and is suitable for various textiles such as cotton, linen, silk, and wool. The color fastness to washing and rubbing reaches level 4 or higher, and the color fastness to sunlight reaches level 3 or higher.

Description

Technical Field

[0001] This invention relates to the field of natural plant dyeing technology for textiles, specifically to a method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red wolfberry pulp. Background Technology

[0002] Natural plant dyeing, with its environmentally friendly raw materials, skin-friendly and non-irritating finished products, and natural and soft colors, has become an important development direction in the textile dyeing field, aligning with the current industry demand for green textiles. Goji berries, a unique Chinese medicinal and edible ingredient, are rich in natural coloring active ingredients such as carotenoids and goji polysaccharides, possessing excellent natural dyeing potential. Therefore, they are being gradually applied to plant dyeing of textiles. However, existing goji berry-related textile dyeing processes still have many technical shortcomings, making large-scale practical application difficult.

[0003] Current goji berry dyeing processes mostly use dried goji berries as raw materials, extracting dyes through high-temperature boiling. This method not only thermally destroys the natural pigments in goji berries, resulting in low pigment extraction efficiency, but also causes a significant loss of active dyeing components, leading to light-colored, grayish, and uneven textiles that fail to achieve a rich color effect. Traditional goji berry dyeing processes generally use alum as a single mordant for color fixation, achieving only a simple bond between the dye and fiber. The limited number of dye adsorption sites on the fiber surface and the weak binding force between dye molecules and fiber result in textiles with low wash fastness and rubbing fastness. They are prone to fading during washing or daily rubbing, and their lightfastness fails to meet everyday practical standards.

[0004] To improve the color fastness of plant dyeing, some existing technologies use chemical fixing agents containing formaldehyde and heavy metals. While these can improve the color fastness to some extent, they completely violate the environmental protection principles of natural plant dyeing. Furthermore, these fixing agents cause textiles to lose their skin-friendly properties, making them unsuitable for use in intimate apparel, infant clothing, and other similar applications. Meanwhile, pure plant-based color fastening systems have not yet formed a mature and stable process that can be mass-produced. The process parameters are set in a crude manner, lacking precise control over temperature, liquor ratio, and reaction time, resulting in poor color consistency and insufficient color fastness stability of the dyed products.

[0005] Furthermore, the existing wolfberry dyeing process has unreasonable process connections, and the extraction, dyeing, and fixing steps lack coordinated design. This not only increases production energy consumption but also further reduces the dyeing efficiency. These problems together limit the promotion and application of natural wolfberry dyeing technology in the textile field. Therefore, developing a dyeing and fixing method for wolfberry pulp textiles that takes into account natural and environmentally friendly properties, high dyeing rate, high color fastness, and stable and controllable process has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing natural dyeing processes for wolfberry textiles, such as low pigment extraction efficiency, light coloring, poor color fastness, unstable processes, and some color-fixing schemes that violate environmental protection principles, this invention provides a natural dyeing and composite tie-dyeing color-fixing method for textiles based on Ningxia red wolfberry pulp. This method achieves high dye uptake and high color fastness of the finished product, while ensuring that the entire process is natural and environmentally friendly, free of harmful chemical reagents, and with precise and controllable process parameters. It is suitable for the large-scale production of various textiles and solves the color and fastness problems of traditional processes.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red goji berry pulp, the specific process steps of which are as follows:

[0008] Step 1: Extraction of wolfberry pulp. Fresh, mature, and mold-free Ningxia red wolfberries are selected as raw materials. After removing impurities through bubbling and spraying washing, unqualified fruits are sorted and removed by a combination of manual and mechanical methods. The processed fresh fruits are crushed into pulp. After removing wolfberry seeds and coarse pulp residue, coarse filtration and fine filtration are carried out in sequence. After high-pressure homogenization, the sugar and acidity of the pulp are adjusted. Low-temperature pasteurization or UHT ultra-high temperature instantaneous sterilization is used for aseptic filling. The pulp is cooled in stages to obtain wolfberry pulp.

[0009] Step 2: Fabric modification pretreatment. Wash the fabric to be dyed in 60℃ warm water for refining treatment. Add desizing powder and react fully. Rinse with clean water and wring until semi-dry. Prepare a color-fixing solution composed of alum and chitosan. Put the fabric to be dyed into the color-fixing solution for heat preservation treatment. After completion, take it out and wring until semi-dry.

[0010] Step 3: Preparation of wolfberry pulp dye solution. Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use.

[0011] Step 4: Constant temperature dyeing. Immerse the pretreated fabric in the prepared wolfberry pulp dyeing solution for pre-soaking, and then dye it under constant temperature conditions. During the dyeing process, keep stirring slowly and turn the fabric over regularly. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0012] Step 5: Composite mordant fixation. The fabric, after being rinsed with water, is immersed in a formaldehyde-free cationic fixative and subjected to mordant fixation treatment under constant temperature conditions, so that the dye, fiber and fixative form a stable bond structure.

[0013] Step 6: Color Locking and Fixing. Place the mordated and fixed fabric in a low-temperature environment to dry, thereby sealing and fixing the dye. Then, gently wash the fabric with clean water and air dry to complete the entire dyeing and fixing process.

[0014] This invention provides a method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red goji berry pulp, which has the following beneficial effects:

[0015] This invention directly uses the cold-pressed pulp of fresh Ningxia red goji berries as dye, abandoning the traditional high-temperature boiling extraction method of dried goji berries. It fully preserves the natural active dyeing components such as carotenoids and goji polysaccharides in goji berries, which greatly improves the binding efficiency of dye to textile fibers. The dyed textiles exhibit a uniform and bright warm orange-yellow and orange-red color scheme. Furthermore, the color depth can be precisely controlled by adjusting the dyeing temperature, time, and other process parameters, resulting in a significant improvement in color saturation and consistency.

[0016] This invention also pre-modifies the fabric by using a modified liquid composed of alum and chitosan, which increases the number of dye adsorption sites on the surface of the textile fibers, allowing dye molecules to bind more fully with the fibers. Subsequently, a formaldehyde-free cationic fixing agent is used to construct a composite mordant system, which enables the dye, fiber, and mordant to form a stable three-dimensional cross-linked structure, greatly enhancing the binding force between the dye and the fiber. The final product has a color fastness to soaping and rubbing that reaches level 4 or above, and a color fastness to sunlight that reaches level 3 or above, which fully meets the daily practical standards of textiles and can be washed and used normally.

[0017] Furthermore, this invention does not use any harmful chemical fixing agents containing formaldehyde or heavy metals throughout the entire process. The core dye raw material is Ningxia red goji berries, which are both food and medicine. The finished product is skin-friendly and non-irritating, with high safety. It can be widely used in scenarios with high safety requirements, such as infant clothing and intimate textiles, thus maintaining the core environmental advantages of natural plant dyeing.

[0018] The process parameters of this invention are precisely controllable, with clear limits on the temperature, time, and liquor ratio for dyeing, fixing, and drying. This improves the stability and consistency of the dyed products, and the process steps are logically connected, significantly shortening the extraction and dyeing time and reducing production energy consumption, making it suitable for industrial-scale mass production. Furthermore, the dyeing and fixing methods of this invention have wide applicability, applicable to various textiles such as cotton, linen, silk, wool, knitted fabrics, and home textiles. This overcomes the limitations of traditional wolfberry dyeing processes and expands the application scope of natural plant dyeing techniques in the textile field. Attached Figure Description

[0019] Figure 1 A flowchart illustrating the process flow of this invention (9-step line drawing).

[0020] Figure 2 This is a flowchart of the extraction process of Ningxia red goji berry pulp in this invention;

[0021] Figure 3 This is a schematic diagram of the composite mordant color-fixing mechanism in the invention (fiber-dye-mordant cross-linking structure).

[0022] Figure 4 A bar chart comparing color fastness under different processing conditions. Detailed Implementation

[0023] The technical solution of the present invention will be described in detail below with reference to specific embodiments. The process parameters involved in the embodiments strictly follow the technical solution of the present invention. One embodiment is set for each of cotton, linen, silk, wool, knitted fabrics, and home textiles. A comparative example using traditional wolfberry dyeing process is also set up. By comparing the color fastness index and color effect, the technical advantages of the present invention are verified. In all embodiments and comparative examples, the color fastness test follows the national standard for color fastness of textiles. The color fastness to washing is referenced to GB / T3921, the color fastness to rubbing is referenced to GB / T3920, and the color fastness to sunlight is referenced to GB / T8427.

[0024] Example 1

[0025] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of cotton fabrics) is as follows:

[0026] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are selected and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After low-temperature pasteurization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0027] 2. Fabric modification pretreatment: Wash the cotton fabric in 60℃ warm water for 10 minutes for refining treatment, add desizing powder and react fully, then rinse with clean water and wring until semi-dry; prepare a color-fixing solution with 2% alum and 0.8% chitosan, bath ratio 1:20, adjust the pH of the color-fixing solution to 4.5, immerse the cotton fabric in the color-fixing solution, keep it at 40℃ for 20 minutes, and then wring until semi-dry;

[0028] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0029] 4. Constant temperature dyeing: Immerse the pretreated cotton fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 60℃ for 40 minutes with a liquor ratio of 1:20. During the dyeing process, keep stirring slowly and turn the fabric 3 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0030] 5. Compound mordant color fixing: Immerse the cotton fabric after rinsing with water in a formaldehyde-free cationic color fixing agent and keep it at a constant temperature of 35℃ for 30 minutes for mordant color fixing treatment.

[0031] 6. Color fixing: Place the mordated cotton fabric in a low temperature environment of 60℃ to dry, then wash the fabric lightly with clean water, and air dry to complete the dyeing and color fixing.

[0032] According to the test results, the finished cotton fabric of this embodiment is a uniform warm orange color, with a color fastness of 4 for washing with soap, a color fastness of 4 for rubbing, and a color fastness of 3 for sunlight.

[0033] Example 2

[0034] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of linen fabrics) is as follows:

[0035] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are selected and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After low-temperature pasteurization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0036] 2. Fabric modification pretreatment: The linen fabric is washed in 60℃ warm water for 10 minutes for refining treatment. After adding desizing powder and reacting fully, it is rinsed with clean water and wrung out until semi-dry. Prepare a color-fixing solution with 2% alum and 0.8% chitosan, a liquor ratio of 1:20, and adjust the pH of the color-fixing solution to 4.6. Immerse the linen fabric in the color-fixing solution and keep it at 40℃ for 22 minutes. After completion, take it out and wring it out until semi-dry.

[0037] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0038] 4. Constant temperature dyeing: Immerse the pretreated linen fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 70℃ for 60 minutes with a liquor ratio of 1:30. During the dyeing process, keep stirring slowly and turn the fabric 4 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0039] 5. Compound mordant color fixing: Immerse the linen fabric, after rinsing with clean water, in a formaldehyde-free cationic color fixing agent and keep it at a constant temperature of 40℃ for 40 minutes for mordant color fixing treatment.

[0040] 6. Color Locking and Fixing: Place the mordated and fixed linen fabric in a low-temperature environment of 70℃ to dry, then gently wash the fabric with clean water, and air dry to complete the dyeing and color fixing process.

[0041] According to the test results, the finished linen fabric of this embodiment is a uniform warm orange-yellow color, with a color fastness of 4 for washing with soap, a color fastness of 4 for rubbing, and a color fastness of 3 for sunlight.

[0042] Example 3

[0043] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of silk fabrics) is as follows:

[0044] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying washing to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are sorted and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After UHT ultra-high temperature instantaneous sterilization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0045] 2. Fabric modification pretreatment: Wash the silk fabric in 60℃ warm water for 10 minutes for refining treatment, add desizing powder and react fully, then rinse with clean water and wring until semi-dry; prepare a color-fixing solution with 2% alum and 0.8% chitosan, bath ratio 1:20, adjust the pH of the color-fixing solution to 4.8, immerse the silk fabric in the color-fixing solution, keep it at 40℃ for 28 minutes, and after completion, take it out and wring until semi-dry;

[0046] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0047] 4. Constant temperature dyeing: Immerse the pretreated silk fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 75℃ for 70 minutes with a liquor ratio of 1:40. During the dyeing process, keep stirring slowly and turn the fabric 4 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0048] 5. Composite mordant color fixing: Immerse the silk fabric after rinsing with water in a formaldehyde-free cationic color fixing agent and keep it at a constant temperature of 50℃ for 50 minutes for mordant color fixing treatment.

[0049] 6. Color Locking and Fixing: Place the mordated and fixed silk fabric in a low-temperature environment of 75℃ to dry, then gently wash the fabric with clean water, and air dry to complete the dyeing and color fixing process.

[0050] According to the test results, the finished silk fabric of this embodiment is uniformly orange-red, with a color fastness of 4-5 for soap washing, a color fastness of 4 for rubbing, and a color fastness of 3 for sunlight exposure.

[0051] Example 4

[0052] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of woolen fabrics) is as follows:

[0053] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying washing to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are sorted and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After UHT ultra-high temperature instantaneous sterilization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0054] 2. Fabric modification pretreatment: Wash the wool fabric in 60℃ warm water for 10 minutes for refining treatment, add desizing powder and react fully, then rinse with clean water and wring until semi-dry; prepare a color-fixing solution with 2% alum and 0.8% chitosan, bath ratio 1:20, adjust the pH of the color-fixing solution to 5.0, immerse the wool fabric in the color-fixing solution, keep it at 40℃ for 30 minutes, and after completion, take it out and wring until semi-dry;

[0055] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0056] 4. Constant temperature dyeing: Immerse the pretreated woolen fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 80℃ for 80 minutes with a liquor ratio of 1:45. During the dyeing process, keep stirring slowly and turn the fabric 5 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0057] 5. Composite mordant color fixing: Immerse the woolen fabric, after rinsing with water, in a formaldehyde-free cationic color fixing agent and keep it at a constant temperature of 55℃ for 60 minutes for mordant color fixing treatment.

[0058] 6. Color fixing: Place the mordated woolen fabric in a low-temperature environment of 80℃ to dry, then wash the fabric lightly with clean water, and air dry to complete the dyeing and color fixing process.

[0059] According to the test results, the finished woolen fabric of this embodiment is a uniform deep orange-red color, with a color fastness of 4 for washing with soap, a color fastness of 4 for rubbing, and a color fastness of 3-4 for sunlight.

[0060] Example 5

[0061] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of knitted fabrics) is as follows:

[0062] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are selected and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After low-temperature pasteurization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0063] 2. Fabric modification pretreatment: Wash the knitted fabric in 60℃ warm water for 10 minutes for refining treatment, add desizing powder and react fully, then rinse with clean water and wring until semi-dry; prepare a color-fixing solution with 2% alum and 0.8% chitosan, liquor ratio 1:20, adjust the pH of the color-fixing solution to 4.7, immerse the knitted fabric in the color-fixing solution, keep it at 40℃ for 25 minutes, and after completion, take it out and wring until semi-dry;

[0064] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0065] 4. Constant temperature dyeing: Immerse the pretreated knitted fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 65℃ for 50 minutes with a liquor ratio of 1:35. During the dyeing process, keep stirring slowly and turn the fabric 3 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0066] 5. Compound mordant color fixing: Immerse the knitted fabric, which has been rinsed with water, in a formaldehyde-free cationic color fixing agent and keep it at a constant temperature of 45℃ for 45 minutes for mordant color fixing treatment.

[0067] 6. Color Locking and Fixing: Place the mordated and fixed knitted fabric in a low-temperature environment of 65℃ to dry, then gently wash the fabric with clean water, and air dry to complete the dyeing and color fixing process.

[0068] According to the test results, the finished knitted fabric of this embodiment is a uniform warm orange-yellow color, with a color fastness of 4 for washing with soap, a color fastness of 4 for rubbing, and a color fastness of 3 for sunlight.

[0069] Example 6

[0070] A method for natural dyeing and composite tie-dyeing color fixing of textiles based on Ningxia red goji berry pulp (natural dyeing and composite tie-dyeing color fixing of home textiles) is as follows:

[0071] 1. Extraction of Goji Berry Puree: Fresh, mature, and mold-free Ningxia red goji berries are selected as raw materials. After bubbling and spraying washing to remove mud, pesticide residues, and impurities, rotten berries, branches, leaves, and unqualified berries are sorted and removed by a combination of manual and mechanical methods. The processed fresh berries are crushed into a puree, and after removing goji berry seeds and coarse pulp, they are subjected to coarse and fine filtration. After high-pressure homogenization, the sugar and acidity of the puree are adjusted to the standard values. After UHT ultra-high temperature instantaneous sterilization, it is aseptically filled and cooled in stages to obtain goji berry puree.

[0072] 2. Fabric modification pretreatment: Wash the home textiles in 60℃ warm water for 10 minutes for refining treatment, add desizing powder and react fully, then rinse with clean water and wring until semi-dry; prepare a color-fixing solution with 2% alum and 0.8% chitosan, bath ratio 1:20, adjust the pH of the color-fixing solution to 4.9, immerse the home textiles in the color-fixing solution, keep warm at 40℃ for 27 minutes, and then wring until semi-dry;

[0073] 3. Preparation of wolfberry pulp dye solution: Take the above-mentioned wolfberry pulp directly as the raw material for dye solution, adjust the concentration of dye solution to 90%, and heat the dye solution to 40℃ for later use;

[0074] 4. Constant temperature dyeing: Immerse the pretreated home textile fabric in the prepared wolfberry pulp dyeing solution for 10 minutes, and then dye it at a constant temperature of 85℃ for 90 minutes with a liquor ratio of 1:50. During the dyeing process, keep stirring slowly and turn the fabric 5 times in the middle. After dyeing, take out the fabric and rinse it with clean water until there is no floating color.

[0075] 5. Compound mordant color fixing: Immerse the home textiles after rinsing with clean water in a formaldehyde-free cationic color fixing agent and keep them at a constant temperature of 52℃ for 55 minutes for mordant color fixing treatment.

[0076] 6. Color Locking and Fixing: Place the mordated and fixed home textile fabric in a low-temperature environment of 78℃ to dry, then gently wash the fabric with clean water, and air dry to complete the dyeing and color fixing process.

[0077] According to the test results, the finished home textile fabric of this embodiment is uniformly orange-red, with a color fastness of 4 for soap washing, a color fastness of 4 for rubbing, and a color fastness of 3 for sunlight exposure.

[0078] Comparative Example

[0079] The traditional wolfberry dyeing process for cotton fabrics is as follows:

[0080] 1. Extraction of wolfberry dye: Dried wolfberries were selected as raw materials, and water was added and boiled at high temperature for 30 minutes. After filtration, wolfberry dye solution was obtained.

[0081] 2. Fabric pretreatment: Wash the cotton fabric with clean water and wring it until semi-dry; no modification treatment is performed.

[0082] 3. Dyeing: Immerse the cotton fabric in wolfberry dye solution and dye at 90℃ for 60 minutes with a liquor ratio of 1:20. Rinse with clean water after dyeing.

[0083] 4. Color fixing: Using alum as a single mordant, immerse the cotton fabric in the alum solution, keep it at 50℃ for 30 minutes, rinse with clean water after color fixing, and air dry naturally in the shade.

[0084] Tests showed that the finished cotton fabric of this comparative example was a pale yellow with a light gray hue, the color was grayish and uneven, the color fastness to washing with soap was grade 2, the color fastness to rubbing was grade 2, the color fastness to sunlight was grade 1, and obvious color fading occurred after washing.

[0085] Conclusions of the comparison between the examples and the comparative examples

[0086] In Examples 1-6 of this invention, cotton, linen, silk, wool, knitted fabrics, and home textiles, after dyeing and color fixing, all exhibit a uniform and full warm orange-yellow or orange-red hue, without any graying or uneven coloring. Furthermore, their color fastness to washing with soap reaches level 4 or higher, their color fastness to rubbing reaches level 4 or higher, and their color fastness to sunlight reaches level 3 or higher, meeting the daily practical standards for textiles. In contrast, the comparative example uses a traditional process of high-temperature boiling and extraction of dried goji berries, without fabric modification, and with single alum mordant dyeing. The finished product has a pale and grayish color, and all color fastness indicators are far lower than those of this invention, with severe color fading after washing.

[0087] Therefore, this invention effectively solves the core defects of traditional goji berry dyeing processes by using innovative processes such as cold-pressed goji berry pulp to retain active ingredients, alum-chitosan fabric pre-modification, formaldehyde-free cationic color-fixing agent composite mordant dyeing, and low-temperature dyeing and setting. It significantly improves the color effect and color fastness of the dyed products, and the entire process is environmentally friendly and natural, making it suitable for a variety of textiles.

[0088] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red goji berry pulp, characterized in that, Follow these steps in sequence: Step 1: Extraction of wolfberry pulp to obtain highly active wolfberry pulp; Step 2: Fabric modification pretreatment. A color-fixing solution composed of alum and chitosan is used to pre-modify the fabric and increase the fiber adsorption sites. Step 3: Preparation of wolfberry pulp dye solution: The above-mentioned wolfberry pulp is prepared into a dye solution for dyeing. Step 4: Constant temperature dyeing. Immerse the pretreated fabric in the dye bath to complete the constant temperature dyeing process. Step 5: Composite mordant fixation. A formaldehyde-free cationic fixative is used to mordant fix the dyed fabric, so that the dye, fiber and mordant form a stable three-dimensional cross-linked structure. Step 6: Color locking and setting. The fabric after mordant dyeing and color fixing is dried at low temperature and then treated to complete the overall dyeing and color fixing.

2. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 1, characterized in that, The specific steps for extracting wolfberry juice in step 1 are as follows: Fresh, ripe, and mold-free Ningxia red goji berries are selected as raw materials. After impurities are removed by bubbling and spraying, unqualified berries are sorted out by a combination of manual and mechanical methods. The processed fresh fruit is crushed into a pulp and the goji berry seeds and coarse pulp residue are removed. After being subjected to coarse filtration, fine filtration and high pressure homogenization, the sugar and acidity of the pulp are adjusted to the standard value. After low temperature pasteurization or UHT ultra-high temperature instantaneous sterilization, it is aseptically filled. Finally, the goji berry juice was obtained through segmented cooling.

3. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 2, characterized in that, The specific procedures for fabric modification pretreatment in step 2 are as follows: First, wash the fabric to be dyed in 60℃ warm water for 10 minutes to refine it. Add desizing powder and let it react fully. Then rinse it with clean water and wring it until it is half dry. Next, prepare a color-fixing solution with 2% alum and 0.8% chitosan, a liquor ratio of 1:20, and pH adjusted to 4.5-5.

0. Immerse the refined fabric in the color-fixing solution and keep it at 40℃ for 20-30 minutes. Once finished, remove the fabric and wring it until it is semi-dry.

4. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 3, characterized in that, The specific steps for preparing the wolfberry pulp dye solution in step 3 are as follows: The wolfberry pulp obtained according to claim 2 is used directly as the raw material for dyeing solution. The concentration of the wolfberry pulp is adjusted to 90%, and the adjusted wolfberry pulp is heated to 40°C and kept warm for later use.

5. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 4, characterized in that, The specific procedures for isothermal staining in step 4 are as follows: The fabric treated according to claim 3 was immersed in the prepared wolfberry pulp dye solution and pre-soaked at 40°C for 10 minutes. The dye liquor is then heated to 60–85°C for constant temperature dyeing. The dyeing holding time is 40–90 minutes, and the dye liquor ratio is 1:20–1:

50. During the dyeing process, the fabric is slowly stirred and turned over periodically. After dyeing, the fabric is removed and rinsed with clean water until no floating color remains.

6. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 1, characterized in that, The specific steps for composite mordant fixing in step 5 are as follows: After rinsing with clean water, the fabric is immersed in a formaldehyde-free cationic fixing agent and kept at a constant temperature of 35-55℃ for 30-60 minutes to complete the mordant fixing treatment, so that the dye molecules and fabric fibers can be stably combined through the fixing agent.

7. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 1, characterized in that, The specific steps for color locking and setting in step 6 are as follows: The fabric that has undergone composite mordant dyeing and color fixing is dried in a low-temperature environment of 60-80℃ to achieve the sealing and fixation of dye molecules; then the fabric is lightly washed with clean water, and finally the fabric is air-dried to complete the entire dyeing and color fixing process.

8. The method for natural dyeing and composite tie-dyeing of textiles based on Ningxia red wolfberry pulp according to claim 1, characterized in that, This method is applicable to any type of textile, including cotton, linen, silk, wool, knitted fabrics, and home textiles. Textiles dyed using this method exhibit a warm orange-yellow or orange-red hue, and the finished product has a color fastness to soap washing ≥ 4, a color fastness to rubbing ≥ 4, and a color fastness to sunlight ≥ 3.

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