A method of printing on wool tops

Abstract

The application discloses a sliver printing method, which comprises the following steps: 1, configuring a printing paste, wherein the printing paste comprises 35-60 g / l of paste, 10-20 g / l of penetrant, 2-3 g / l of 85% concentration acetic acid, water and dye; when the printing paste is configured, the dye is dissolved first, then the paste is dissolved, and the PH value of the printing paste is adjusted to be acidic; 2, using a printing machine to print the sliver, and immersing the sliver in the printing paste; 3, using saturated steam to perform steaming and mercerizing on the sliver, so that the paste is dissolved, and the dye is promoted to diffuse to the inside of the sliver; and 4, cleaning the paste and residual dye on the surface of the sliver, and controlling drying and moisture regain. Through the above setting, the printing effect and firmness of the sliver can be improved.

Description

Technical Field

[0001] This application relates to the field of textile printing and dyeing technology, and in particular to a method for printing wool strips. Background Technology

[0002] In the textile industry, wool tops refer to strips of wool fabric. They are a key material for producing high-quality textiles and are widely used in the production of various textiles. The process of making wool tops involves combing washed wool fibers into strips, followed by combing and subsequent preparation and finishing processes, ultimately producing standard-compliant wool tops. These wool tops can then be further spun into yarn for making various textiles, such as woolen fabrics and sweaters.

[0003] Woolen strip printing refers to the process of printing various patterns or colors onto woolen strips. This technique is commonly used to produce woolen fabrics with special colors or patterns to meet the market's demand for diversified textiles. However, current woolen strip printing techniques suffer from poor results and insufficient durability. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide a strip printing method that can improve the effect and durability of strip printing.

[0005] To achieve the above objectives, this application adopts the following technical solution: This application provides a method for printing wool stripes, the method comprising: Step 1: Prepare the printing paste, which includes: 35-60 g / L of paste, 10-20 g / L of penetrant, 2-3 g / L of 85% acetic acid, water, and dye; When preparing printing paste, first dissolve the dye, then dissolve the paste, and then adjust the pH value of the printing paste to acidic. Step 2: Use a printing machine to print the wool strips, immersing the wool strips in the printing paste; Step 3: Use saturated steam to steam the wool strips, dissolve the paste, and promote the diffusion of dye into the wool strips; Step 4: Clean the surface of the wool strips of paste and residual dye, and control the drying process to prevent moisture regain.

[0006] As a preferred technical solution, in step 2, the printing pressure of the printing machine is 3.5-4.5MPa, and the machine speed is 5-8 meters / minute.

[0007] As a preferred technical solution, in step 2, after printing the wool strips using a printing machine, a wool combing machine is used to comb the wool strips, with a combing pressure of 0.7-1 MPa.

[0008] As a preferred technical solution, in step 3, before steaming the wool strip with saturated steam, the moisture content and material content of the wool strip are kept at 50%-80%.

[0009] As a preferred technical solution, in step 3, the steaming temperature is 98-102ºC and the steaming time is 30min-1h.

[0010] As a preferred technical solution, step 4, cleaning the surface paste and residual dye of the wool top includes: cold water washing; 40°C warm water washing, with the addition of 1g / l of penetrant and 1g / l of ammonia; repeated washing with 40°C warm water several times; and drying the wool top using a dryer at a temperature of 50-90°C and a dryer speed of 6-10 meters / minute.

[0011] As a preferred technical solution, during the 40℃ warm water rewash, the machine passes through several rolling mills and is rinsed with 40℃ warm water at a water pressure of 1 kPa.

[0012] As a preferred technical solution, the moisture content of the wool tops is maintained at 40%-50% before drying with a dryer, and the moisture content is 12%-18% after drying.

[0013] As a preferred technical solution, the printing paste also includes an anti-staining soaping agent.

[0014] As a preferred technical solution, the pH value of the printing paste is adjusted to acidity, specifically to pH 4-6.

[0015] Compared with the prior art, the beneficial effects of this application are as follows: 1. Improve printing quality: By properly configuring the printing paste and operating the printing machine, you can ensure that the printed pattern is clear, the color is bright and uniform.

[0016] 2. Enhance dye fixation effect: Using saturated steam for steaming helps the dye to fully adhere to the wool fibers, improving the dye fixation rate and color fastness.

[0017] 3. High adaptability: This method is applicable to a variety of dyes and wool top types, and can be flexibly adjusted according to customer needs. Attached Figure Description

[0018] Figure 1 This is a flowchart of a strip printing method according to this application. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0020] like Figure 1As shown, this application provides a method for printing wool stripes, the method comprising: Step 1: Prepare the printing paste, which includes: 35-60 g / L of paste, 10-20 g / L of penetrant, 2-3 g / L of 85% acetic acid, water, and dye; When preparing printing paste, first dissolve the dye, then dissolve the paste, and then adjust the pH value of the printing paste to acidic. Step 2: Use a printing machine to print the wool strips, immersing the wool strips in the printing paste; Step 3: Use saturated steam to steam the wool strips, dissolve the paste, and promote the diffusion of dye into the wool strips; Step 4: Clean the surface of the wool strips of paste and residual dye, and control the drying process to prevent moisture regain.

[0021] Thickeners, also known as pastes, are substances that impart the necessary viscosity to printing pastes, used for the adhesion and fixation of dyes on the yarn. Thickeners include starch, sodium alginate, gum, protein, and animal glue. Starch is commonly used for printing on cellulose fiber fabrics, gum for animal fibers, protein to keep the dye in solution and prevent bleeding, and animal glue is often used for printing on low-grade cotton fabrics. Other types include starch and cellulose derivatives, polyvinyl alcohol, polyacrylonitrile, and polyethylene glycol. In this application, natural gum is used as the thickener. The preferred amount of thickener is 35-40 g / L.

[0022] Penetrants are used to remove excess dye from fabrics printed with reactive, disperse, and other dyes. In this application, the penetrant is a multi-purpose wetting agent, which can improve the penetration of dyes without affecting the clarity of the printed pattern.

[0023] The dyes are water-based dyes specifically used in strip printing. Commonly used dyes for strip printing include black, dark blue, and maroon.

[0024] Acetic acid is an acidic adjuster that is harmless to dyes and fabrics. Using acetic acid to adjust the pH of printing pastes to an acidic range helps with dye fixation and fiber penetration.

[0025] The principle of printing dyes is to use a special paste as a carrier, replacing traditional water. Through physical and chemical adsorption, the dye adheres to the wool fibers, and through diffusion, the dye is evenly distributed within the fibers. Finally, a color-fixing treatment improves the color fastness and stability of the print, thus forming a clear and durable printed pattern on the wool fabric. Specifically: Adsorption of dyes includes physical adsorption and chemical adsorption.

[0026] Physical adsorption refers to the phenomenon where dye molecules adsorb onto the surface of wool fibers through physical interactions (such as weak intermolecular forces like van der Waals forces and hydrogen bonds), due to the presence of numerous micropores and gaps on the fiber surface. While relatively weak, this physical adsorption plays a crucial role in the initial stages of printing, allowing the dye to initially adhere to the fiber and laying the foundation for subsequent chemical bonding processes. For example, certain polar groups in the dye molecule can attract polar sites on the wool fiber surface, thus achieving physical adsorption.

[0027] Chemisorption refers to the process by which dyes bind to wool fibers. Wool fibers are primarily composed of keratin, which contains numerous reactive groups such as amino, carboxyl, and hydroxyl groups. Dye molecules also possess chemical groups that can react with these reactive groups, forming strong chemical bonds such as covalent and ionic bonds, thus firmly binding the dye to the wool fibers. This chemisorption is crucial for the strong adhesion of Tisselan wool printing dyes, ensuring colorfastness. For example, acidic groups such as sulfonic acid groups in dye molecules can form ionic bonds with basic groups such as amino groups on wool fibers.

[0028] Dye diffusion: During the printing process, dyes not only need to be adsorbed onto the surface of wool fibers but also need to diffuse into the fiber interior to achieve uniform dyeing. Wool fibers have a certain internal porous structure, through which dye molecules can penetrate and diffuse into the fiber interior. Printing conditions such as temperature and humidity affect the dye diffusion rate. Generally speaking, higher temperatures intensify molecular motion, accelerating dye diffusion; appropriate humidity can cause fibers to swell, increasing the internal porosity and facilitating dye diffusion. Once the dye molecules have fully diffused into the interior of the wool fibers and chemically bonded to the fibers, a stable printed pattern can be formed.

[0029] Color Fixing Process: After adsorption and diffusion, color fixing treatment is required to further improve the color fastness and stability of the print. Fixing agents react with dye molecules and wool fibers, enhancing the binding force between the dye and fiber and preventing dye from detaching during subsequent washing, rubbing, etc. For example, fixing agents can form cross-linked structures with dye molecules or react with active groups on wool fibers, firmly "locking" the dye molecules onto the fiber. The conditions for color fixing treatment (such as the type and amount of fixing agent, treatment temperature, and time) need to be optimized based on the specific characteristics of the dye and fiber to achieve the best color fixing effect.

[0030] The beneficial effects of this application are as follows: 1. Improve printing quality: By properly configuring the printing paste and operating the printing machine, you can ensure that the printed pattern is clear, the color is bright and uniform.

[0031] 2. Enhance dye fixation effect: Using saturated steam for steaming helps the dye to fully adhere to the wool fibers, improving the dye fixation rate and color fastness.

[0032] 3. High adaptability: This method is applicable to a variety of dyes and wool top types, and can be flexibly adjusted according to customer needs.

[0033] Specifically, in step 1, the pH value of the printing paste is adjusted to acidity, specifically to 4-6, to avoid damage to the properties of the wool fabric due to excessively low pH, and to avoid poor dye fixation due to excessively high pH, ​​which would lead to a decline in printing quality. Preferably, the pH is adjusted to 4-4.5.

[0034] Furthermore, in step 1, the printing paste also includes: a stain-resistant soaping agent. During the soaping process after printing and dyeing, the stain-resistant soaping agent effectively prevents unfixed dyes and hydrolyzed dyes from re-staining the fabric, ensuring vibrant colors and clear patterns. This stain-resistant soaping agent is suitable for wool and silk blended fabrics.

[0035] Specifically, in step 2, the printing pressure of the printing machine is 3.5-4.5 MPa, and the machine speed is 5-8 meters per minute. Under appropriate pressure, the printing head of the printing machine can make closer contact with the yarn overlay fabric, resulting in a clearer and more delicate printed pattern. The slower machine speed also ensures that the pigment has enough time to contact and penetrate the yarn overlay fabric, thereby improving the clarity of the printed pattern. At the same time, sufficient pressure (yarn overlay moisture content and material content 50%-80%) ensures that the pigment is fully transferred to the fabric, resulting in a richer and more vibrant color. The appropriate machine speed also helps to evenly distribute the pigment on the fabric, avoiding uneven color distribution. When starting the printing and dyeing process, pay attention to weighing the yarn overlay ratio and control the liquid level in the dye bath to maintain a consistent level based on the amount of liquid overlay.

[0036] More specifically, in step 2, after printing the yarn strips using a printing machine, a carding machine is used to card the yarn strips. The carding pressure of the carding machine is 0.7-1 MPa. The carding machine repeatedly combs the surface of the yarn strips using metal needles, which can twist the fibers into more uniform "yarn," thereby improving the uniformity and overall quality of the yarn strips. During the carding process, the carding machine can remove impurities, burrs, and loose fibers from the surface of the yarn strips, making the yarn strips cleaner and smoother. Appropriate carding pressure (yarn strip moisture content and material content 50%-80%) ensures that the printed pattern on the yarn strips is not damaged during the carding process, keeping the pattern intact and clear. The carding process helps the pigment penetrate deeper into the yarn strip fibers, thereby enhancing the adhesion of the printed pattern and making it more durable.

[0037] Specifically, in step 3, before steaming the sliver with saturated steam, the sliver should be kept at a moisture content and material content of 50%-80%. The high temperature and high pressure environment of saturated steam helps dye molecules penetrate better into the sliver fibers, reacting chemically or physically with the fibers, thereby improving the dye fixation rate. Appropriate sliver moisture content and material content (50%-80% moisture and material content) ensure that the dye penetrates evenly into the fibers under steam, avoiding dye accumulation on the fiber surface or uneven penetration. It should be noted that sliver material refers to dyes, penetrants, acetic acid, and anti-staining detergents that adhere to the sliver surface or penetrate into the sliver fibers during the sliver printing process.

[0038] More specifically, in step 3, the steaming temperature is 98-102ºC, and the steaming time is 30 min-1 h. Within this temperature range (98-102ºC), dye molecules can more effectively penetrate into the interior of the wool fibers and react chemically or physically with the fibers, thereby improving the dye fixation rate. High temperature helps accelerate the movement of dye molecules, making it easier for them to enter the fiber gaps and bind with the fibers. An appropriate steaming time (30 min-1 h) ensures that the dye is evenly distributed inside the fibers, avoiding dye accumulation or uneven penetration. A long steaming process helps dye molecules to fully diffuse and penetrate, resulting in a uniform color in the wool.

[0039] Specifically, in step 4, cleaning the surface of the wool strip of paste and residual dye includes: Cold water rinsing initially removes most of the paste and loose dye from the surface of the wool strips, laying the foundation for subsequent cleaning steps.

[0040] Wash with 40℃ warm water, and add 1g / L of penetrant and 1g / L of ammonia. The addition of penetrant allows for more effective penetration into the wool fibers, breaking down and dispersing the paste and dye residue in the fibers. The weak alkalinity of ammonia helps neutralize any acidic substances that may be present, and its strong diffusion ability allows it to penetrate into the interior of the wool, reducing the amount of bound acid in the wool, thereby further improving the cleaning effect.

[0041] Wash several times with 40℃ warm water. Multiple washes ensure that all residues on the surface of the wool top are thoroughly removed, guaranteeing its cleanliness. Using 40℃ warm water during the washing process avoids damage to the wool fibers from high temperatures, preserving the original quality of the fibers.

[0042] The wool tops are dried using a dryer at a temperature of 50-90℃ and a speed of 6-10 meters per minute.

[0043] A series of steps, including cold water washing, 40℃ warm water washing (with penetrant and ammonia), 40℃ warm water rewash, and dryer drying, are used to clean the paste and residual dye on the surface of the wool top. This can significantly improve the cleaning effect, protect the quality of the wool top fibers, increase production efficiency and save energy, and enhance the adaptability of the product.

[0044] More specifically, during the 40°C warm water rewash, the fibers are rinsed through several passes at a pressure of 1 kPa. This multiple rinsing passes ensure that each pass fully contacts the wool sliver, resulting in a more comprehensive cleaning of both the surface and interior. The 1 kPa water pressure ensures that the water penetrates the wool fibers without damaging the fiber structure due to excessive pressure; this moderate water pressure helps to evenly rinse the wool sliver, avoiding either over- or under-rinsing in certain areas.

[0045] More specifically, the moisture content of the wool sliver should be maintained at 40%-50% before drying in a dryer, and 12%-18% after drying. Maintaining an appropriate moisture content (40%-50%) before entering the dryer can shorten the drying time because relatively less moisture needs to be removed, which helps improve the dryer's production capacity and overall processing efficiency. Maintaining an appropriate moisture content before drying helps reduce the mechanical and thermal stress on the wool fibers during the drying process, which helps avoid fiber damage such as breakage, deformation, or loss of luster. Appropriate moisture content and drying conditions can maintain the softness and elasticity of the wool fibers. A post-drying moisture content of 12%-18% helps ensure product stability and consistency, and an appropriate moisture content can prevent the wool sliver from becoming moldy or deteriorating during storage and transportation.

[0046] The wool strip printing method of this application utilizes the coloring principle of printing, optimizes the viscosity of the dye liquor, uses pre-dyed wool, and after printing and dyeing, achieves stable color fastness through reasonable steaming and color fixing.

[0047] Color fastness of printed fabric: dry rubbing ≥ 3; wet rubbing ≥ 2-3; scouring fastness (staining of white wool) ≥ 3-4 (washing fastness (staining of fabric after scouring) ≥ 3).

[0048] This application provides a sliver manufactured by the sliver printing method of this application, and the color fastness of the sliver is shown in Table 1.

[0049] Table 1 Color fastness of wool strips manufactured by the wool strip printing method of this application Color fastness to perspiration / grade Color change ≥4 staining ≥4 Water fastness / grade Color change ≥4 staining ≥4 Ironing color fastness / grade Color change ≥4 staining ≥4 Color fastness to rubbing / grade dry friction ≥4 wet friction ≥3-4 (Dark 3) Wash fastness / grade Color change ≥4 staining ≥4 Dry cleaning fastness / grade Color change ≥4 staining ≥4 It should be noted that the terms "first," "second," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. "A plurality" or "several" indicates at least two. Unless otherwise stated, terms such as "front," "back," "left," "right," "lower," and / or "upper" are for illustrative purposes only and are not limited to a location or spatial orientation. Terms such as "comprising" or "including" indicate that the elements or objects preceding "comprising" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0050] The singular forms “a,” “the,” and “the” used in this application specification and appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0051] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for printing wool stripes, characterized in that, The wool strip printing method includes: Step 1: Prepare the printing paste, which includes: 35-60 g / L of paste, 10-20 g / L of penetrant, 2-3 g / L of 85% acetic acid, water, and dye; When preparing printing paste, first dissolve the dye to ensure that the dye is fully dispersed in the water, then dissolve the paste, then add the penetrant, and finally adjust the pH of the printing paste to acidic with acetic acid. Step 2: Use a printing machine to print wool strips, immersing the wool strips in the printing paste; Step 3: Use saturated steam to steam the wool strips, dissolve the paste, and promote the diffusion of dye into the wool strips; Step 4: Clean the surface of the wool strips of paste and residual dye, and control the drying process to prevent moisture regain.

2. The method for printing felt strips according to claim 1, characterized in that, In step 2, the printing pressure of the printing machine is 3.5-4.5 MPa, and the machine speed is 5-8 meters per minute.

3. The method for printing felt strips according to claim 1 or 2, characterized in that, In step 2, after printing the wool strips using a printing machine, a wool combing machine is used to comb the wool strips. The combing pressure of the wool combing machine is 0.7-1 MPa.

4. The method for printing felt strips according to claim 1, characterized in that, In step 3, before steaming the wool strip with saturated steam, the moisture content and material content of the wool strip are kept at 50%-80%.

5. The method for printing felt strips according to claim 1 or 4, characterized in that, In step 3, the steaming temperature is 98-102ºC and the steaming time is 30min-1h.

6. The method for printing felt strips according to claim 1, characterized in that, In step 4, cleaning the surface of the wool strip to remove the paste and residual dye includes: Wash with cold water; Wash with 40℃ warm water, and add 1g / l of penetrant and 1g / l of ammonia water; Wash several times with 40℃ warm water; The wool tops are dried using a dryer at a temperature of 50-90℃ and a speed of 6-10 meters per minute.

7. The method for printing felt strips according to claim 6, characterized in that, During the 40℃ warm water rewash, the water passes through several rolling mills and is rinsed with 40℃ warm water at a pressure of 1 kPa.

8. The method for printing felt strips according to claim 6, characterized in that, Before drying the wool tops, maintain a moisture content of 40%-50% and after drying, the moisture content should be 12%-18%.

9. The method for printing felt strips according to claim 1, characterized in that, The printing paste also includes an anti-staining soaping agent.

10. The method for printing felt strips according to claim 1, characterized in that, The pH of the printing paste is adjusted to acidity, specifically to pH 4-6.

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