Lyocell yarn surface antigen fibrillation treatment method

Abstract

This invention belongs to the field of textile technology, specifically relating to a method for surface antigen fiberization treatment of lyocell yarn. An anionic antigen fiberization auxiliary agent, soda ash, and water are prepared into a working solution. After unwinding, the yarn passes through the reaction tank of a single-yarn continuous antigen fiberization treatment device, where the yarn surface reacts with the working solution. After being extruded by an extrusion device and air-dried by rotation in a drum, it is wound into loose cones by a digital winding device. The treated loose cones are then fixed in color using a steamer. The fixed cones are then neutralized, washed, and dried using a cone dyeing machine. By strictly controlling the time the yarn passes through the reaction tank to within 0.1 seconds, instantaneous surface adsorption of the working solution is achieved. This ensures that the auxiliary agent reacts only on the outer layer of the yarn, forming a robust protective shell, while the core fibers remain in an unreacted, natural state, thus fully preserving the flexibility of the lyocell fiber core.

Description

Technical Field

[0001] This invention belongs to the field of textile technology, specifically relating to a method for anti-fiberization treatment of Lyocell yarn surface antigens. Background Technology

[0002] Lyocell fiber is a new type of green and environmentally friendly regenerated cellulose fiber with advantages such as high strength, good moisture absorption, and easy dyeing. Fabrics woven from it have advantages such as silk-like luster, low shrinkage, high comfort, and good breathability. However, it is prone to fibrillation under wet conditions and mechanical friction, that is, the fiber surface splits longitudinally into microfibers, which leads to fabric pilling, fuzzing, an old appearance, and a poor hand feel, thus restricting its application in high-end textiles.

[0003] Currently, the mainstream technical approach to improving fibrillation of lyocell fibers is "additive," mainly divided into two categories: First, cross-linking the fibers during the spinning stage. The cross-linking agent forms covalent bonds between cellulose molecular chains within the fiber. Based on the degree of cross-linking, it is classified as uncross-linked lyocell fibers (G100 fibers), semi-cross-linked lyocell fibers (LF fibers), and cross-linked lyocell fibers (A100 fibers). However, the cross-linking performance of cross-linked lyocell fabrics decreases after dyeing and finishing, leading to pilling and fuzzing issues. Second, pad-cross-linking is performed during the dyeing and finishing stage of lyocell fabrics. This method uses large amounts of salt and alkali and suffers from uneven cross-linking, hardened hand feel, high energy consumption, and the generation of saline wastewater. However, existing technologies generally present a fundamental contradiction: to achieve better fibrillation, the cross-linking reaction often needs to penetrate deep into the fiber, inevitably damaging the natural crystalline regions and hydrogen bond structure of the fiber core, resulting in a significant decrease in yarn or fabric strength and a hardened hand feel.

[0004] Patent CN119372852A discloses a method for preventing fibrillation in lyocell yarn. This method employs a continuous impregnation, contact drying, and baking process, using a high concentration of resin (60-100 g / L) and catalyst, and achieving cross-linking at a high temperature of 160-200℃ for a relatively long time: drying for 0.5-6 seconds and baking for 0.5-3 seconds. However, this method still has the following shortcomings: First, this patent aims to achieve overall penetration cross-linking, using impregnation to allow the cross-linking agent to uniformly penetrate the yarn cross-section, achieving complete cross-linking inside and outside the fiber. This affects the natural structure of the core fiber, which is detrimental to maintaining the original softness and high strength of the yarn. Second, the crosslinking agent used in this patent is a wrinkle-free resin system, employing amide-formaldehyde resins such as etherified dimethyloldihydroxyvinyl urea (DMDHEU) and corresponding catalysts. Under high-temperature baking, these resins undergo acetalization with cellulose, potentially releasing formaldehyde. The reaction mechanism involves dry-heat baking to form a film, relying on high-temperature contact baking to promote resin crosslinking within and on the surface of the fiber, leading to film formation. This high-temperature, long-duration contact drying and baking process easily causes heat damage to the fiber, affecting the yarn's hand feel and mechanical properties. Third, the process ends with winding after baking, without a dedicated washing step, resulting in unreacted resin and formaldehyde residue in the yarn. Fourth, the use of high-concentration resins and catalysts not only increases costs but also easily causes chemical residues and environmental pollution.

[0005] Therefore, the industry urgently needs a new method that can fundamentally solve the above problems. That is, to develop a treatment technology for lyocell yarn that can achieve efficient and continuous production, precisely control the cross-linking reaction to occur only on the yarn surface, achieve excellent anti-fiberization effect, and maximize the preservation of the natural strength and soft hand feel of the core fiber, while the process is clean and environmentally friendly. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a method for antigen-fibrillated treatment of lyocell yarn surface. This method involves rapidly passing the yarn through a working solution and adsorbing the antigen, forming a ring-shaped reaction zone on the outer surface of the yarn. This process produces antigen-fibrillated lyocell yarn without affecting the feel of the yarn.

[0007] The method for treating the surface antigens of Lyocell yarn according to the present invention includes the following steps:

[0008] (1) Preparation of working solution: Prepare working solution by mixing anionic antigen fibrillating agent, soda ash and water;

[0009] (2) Single yarn antigen fiberization reaction: After unwinding, the yarn passes through the reaction tank of the single yarn continuous antigen fiberization treatment device. The yarn surface reacts with the working solution. After being squeezed by the extrusion device and dried by rotating drum, it is wound into loose bobbin by the digital winding device. The structural schematic diagram of the single yarn continuous antigen fiberization treatment device is shown below. Figure 1 As shown;

[0010] (3) Steaming and fixing the yarn: Use a steamer to fix the color of the treated loose yarn cones;

[0011] (4) Post-treatment: The fixed yarn is neutralized, washed with water and dried using a yarn dyeing machine; the cross-sectional diagram of the yarn after anti-fibrillation treatment is shown in the figure. Figure 2 As shown;

[0012] In step (2), the time for the yarn to pass through the reaction tank is less than 0.1s.

[0013] The anionic antigenic fiberizing agent described in step (1) is KR-6347, a commercially available product of Qingdao Kerun Biotechnology Co., Ltd., which contains a multifunctional compound that can react with cellulose hydroxyl groups. This agent reacts only on the outer layer of the yarn through extremely short-term surface adsorption, intentionally keeping the core fibers unreacted. Under alkaline conditions, this anionic antigenic fiberizing agent undergoes a nucleophilic substitution reaction with cellulose hydroxyl groups through a mechanism similar to reactive dyeing, forming covalent bonds. Unlike the commonly used wrinkle-free resin systems in the prior art, the KR-6347 described in this invention completes the reaction in a humid and hot environment provided by saturated steam, resulting in milder conditions and easier control of the reaction depth.

[0014] In step (1), the amount of anionic antigen fibrinolytic agent used is 20-50 g / L, and the amount of soda ash used is 30-40 g / L.

[0015] The single yarn continuous antigen fiberization treatment device in step (2) consists of an unwinding device, a reaction tank, an extrusion device, a rotating drum, and a digital winding device.

[0016] The yarn in step (2) is either Lyocell raw yarn or colored yarn.

[0017] The density of the loose-knitted yarn in step (2) is 0.38-0.48 g / cm³. 3 .

[0018] In step (2), the speed at which the yarn passes through the reaction tank is 600-800 m / min.

[0019] After the yarn leaves the reaction tank in step (2), the liquid carrying rate is controlled to be 90-100% by the extrusion device.

[0020] The color-fixing temperature in step (3) is 100-130℃, and the time is 10-30 min.

[0021] The neutralization in step (4) involves adjusting the pH to 6-7 with acid.

[0022] The temperature of the neutralization wash in step (4) is 30-50℃, and the time is 5-20 minutes. This invention includes a dedicated neutralization wash process after the yarn is steamed and fixed to remove residual alkali and unreacted substances, ensuring the purity of the yarn.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1) This invention achieves excellent antigen-fibrillation while preserving the original strength and soft hand feel of the yarn to the greatest extent. By strictly controlling the time the yarn passes through the reaction tank to within 0.1 seconds, instantaneous surface adsorption of the working solution is achieved. This allows the KR-6347 anionic additive to react only in the outer layer of the yarn, forming a robust protective shell, while the core fibers remain in an unreacted, natural state, thus fully preserving the mechanical properties and flexibility of the lyocell fiber core.

[0025] 2) This invention uses a special chemical system and a mild reaction to ensure product safety and fiber health, avoiding the risk of formaldehyde residue. The reaction can be completed in saturated steam at 100-130℃ for wet heat fixation, which is mild and effectively avoids the fiber heat damage and hand hardening caused by traditional dry heat baking at 160-200℃.

[0026] 3) This invention enables continuous high-speed production of single yarns, significantly improving processing efficiency and substantially reducing water, chemical, and energy consumption. A unique continuous single-yarn antigen-fibrillation treatment device integrates reaction, drying, and winding into a single, compact process. This invention enables antigen-fibrillation treatment of single yarns during the winding process, without using salt and reducing soda ash usage by 90%. This results in low cost and high yarn utilization. A major reason for eliminating salt is to minimize the penetration effect and prevent the working solution from seeping into the core.

[0027] 4) The method described in this invention is applicable to both raw and dyed lyocell yarns, exhibiting wide adaptability and resulting in high purity of the final yarn product. The surface adsorption and steam fixing mechanisms have minimal interference with the internal structure of the yarn and do not affect the color of the dyed yarn. The mandatory neutralization washing step thoroughly removes residual alkali and unreacted substances, enabling the yarn to meet safer and cleaner standards for use. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the single-yarn continuous antigen fiberization treatment device of the present invention.

[0029] 1. Digital winding device; 2. Rotary drum; 3. Extrusion device; 4. Reaction tank; 5. Unwinding device.

[0030] Figure 2 This is a schematic diagram of the cross-section of yarn after antigen fibrillation treatment;

[0031] 6. Unreacted portion of the core layer; 7. Reacted portion of the outer layer.

[0032] Figure 3 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Example 1;

[0033] Figure 4 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Example 2;

[0034] Figure 5 This is a microscopic image of the cross-section of the yarn after antigen fibrillation treatment in Example 3;

[0035] Figure 6 This is a microscopic image of the cross-section of the yarn after antigen fibrillation treatment in Example 4;

[0036] Figure 7 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Comparative Example 1;

[0037] Figure 8 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Comparative Example 2;

[0038] Figure 9 This is a microscopic image of the cross-section of yarn after antigen fibrillation treatment in Comparative Example 3. Detailed Implementation

[0039] The present invention will be further described below with reference to the embodiments.

[0040] Unless otherwise specified, all raw materials used in the examples were commercially available.

[0041] KR-6347 was purchased from Qingdao Kerun Biotechnology Co., Ltd.

[0042] Soda ash was purchased from Zibo Lurui Fine Chemical Co., Ltd.

[0043] Example 1

[0044] The method for treating the surface antigens of Lyocell yarn includes the following steps:

[0045] (1) Preparation of working solution: KR-6347 and soda ash are dissolved in water to prepare working solution, wherein the amount of KR-6347 is 20g / L and the amount of soda ash is 30g / L.

[0046] (2) Single yarn antifibrillation reaction: 50s G100 Lyocell raw yarn is selected. The working solution is poured into the reaction tank 4. The yarn is fed in from the tension controller, unwound by the unwinding device 5, and then pressed into the reaction tank 4 by the pressing roller. The working solution is adsorbed on the surface of the yarn. After being squeezed by the polyester sandwich extrusion device 3 and air-dried by the rotating drum 2, it is wound into loose bobbin yarn by the digital winding device 1. The equipment speed is 600m / min, the time for the yarn to pass through the reaction tank is within 0.1s, the extrusion device 3 controls the liquid content of the yarn to be 100%, the moisture content of the wound loose bobbin yarn is 50%, and the density is 0.38g / cm³. 3 .

[0047] (3) Steaming and fixing: The treated loose yarn is placed in a high-temperature and high-pressure steamer and the color is fixed at high temperature using saturated steam. The color fixing temperature is 100℃ and the time is 10min.

[0048] (4) Post-treatment: The steamed and fixed yarn is placed in a yarn dyeing machine for neutralization and washing. HAc is added to adjust the pH to 6, the temperature is 30℃, and the time is 5 minutes. A schematic diagram of the cross-section of the yarn after antigen fibrillation treatment is shown below. Figure 2 As shown, it includes the unreacted core layer 6 and the reacted outer layer 7.

[0049] Example 2

[0050] The method for treating the surface antigens of Lyocell yarn includes the following steps:

[0051] (1) Preparation of working solution: KR-6347 and soda ash are dissolved in water to prepare working solution, wherein the amount of KR-6347 is 30g / L and the amount of soda ash is 35g / L.

[0052] (2) Single yarn antifibrillation reaction: 50s G100 Lyocell raw yarn is selected. The working solution is poured into the reaction tank 4. The yarn is fed in from the tension controller, unwound by the unwinding device 5, and then pressed into the reaction tank 4 by the pressing roller. The working solution is adsorbed on the surface of the yarn. After being squeezed by the polyester sandwich extrusion device 3 and air-dried by the rotating drum 2, it is wound into loose bobbin yarn by the digital winding device 1. The equipment speed is 700m / min, the time for the yarn to pass through the reaction tank is within 0.1s, the extrusion device 3 controls the liquid content of the yarn to be 95%, the moisture content of the wound loose bobbin yarn is 45%, and the density is 0.45g / cm³. 3 .

[0053] (3) Steaming and fixing: The treated loose yarn is placed in a high-temperature and high-pressure steamer and the color is fixed at high temperature using saturated steam. The color fixing temperature is 120℃ and the time is 20min.

[0054] (4) Post-treatment: The steamed and fixed yarn is placed in a yarn dyeing machine for neutralization and washing. HAC is added to adjust the pH to 6.5, the temperature is 40℃, and the time is 10 min. A schematic diagram of the cross-section of the yarn after antigen fibrillation treatment is shown below. Figure 2 As shown, it includes the unreacted core layer 6 and the reacted outer layer 7.

[0055] Example 3

[0056] The method for treating the surface antigens of Lyocell yarn includes the following steps:

[0057] (1) Preparation of working solution: KR-6347 and soda ash are dissolved in water to prepare working solution, wherein the amount of KR-6347 is 50g / L and the amount of soda ash is 40g / L.

[0058] (2) Single yarn antifibrillation reaction: 50s G100 Lyocell raw yarn is selected. The working solution is poured into the reaction tank 4. The yarn is fed in from the tension controller, unwound by the unwinding device 5, and then pressed into the reaction tank 4 by the pressing roller. The working solution is adsorbed on the surface of the yarn. After being squeezed by the polyester sandwich extrusion device 3 and air-dried by the rotating drum 2, it is wound into loose bobbin yarn by the digital winding device 1. The equipment speed is 800m / min, the time for the yarn to pass through the reaction tank is within 0.1s, the extrusion device 3 controls the liquid content of the yarn to be 90%, the moisture content of the wound loose bobbin yarn is 40%, and the density is 0.48g / cm³. 3 .

[0059] (3) Steaming and fixing: The treated loose yarn is placed in a high-temperature and high-pressure steamer and the color is fixed at high temperature using saturated steam. The color fixing temperature is 130℃ and the time is 30min.

[0060] (4) Post-treatment: The steamed and fixed yarn is placed in a yarn dyeing machine for neutralization and washing. HAC is added to adjust the pH to 7, the temperature is 50℃, and the time is 20 min. A schematic diagram of the cross-section of the yarn after antigen fibrillation treatment is shown below. Figure 2 As shown, it includes the unreacted core layer 6 and the reacted outer layer 7.

[0061] Non-preferred embodiment 4

[0062] Same as Example 1, except that the working solution is prepared by dissolving KR-6347 and soda ash in water to prepare the working solution, wherein the amount of KR-6347 is 60g / L and the amount of soda ash is 60g / L.

[0063] Comparative Example 1

[0064] Same as in Example 1, except that the speed is reduced so that the yarn takes 0.5 seconds to pass through the reaction tank 4.

[0065] Comparative Example 2

[0066] Same as Example 1, except that the working solution is prepared as follows: KR-6347, soda ash, sodium sulfate, and penetrant (Rayclean WA-M, Zibo Lurui Fine Chemical Co., Ltd.) are dissolved in water to prepare the working solution, wherein the amount of KR-6347 is 20g / L, soda ash is 30g / L, sodium sulfate is 50g / L, and penetrant is 10g / L.

[0067] Comparative Example 3

[0068] Reproducing Example 7 of Patent CN119372852A

[0069] (1) The working solution is: DMDHEU: 100g / L, urea formaldehyde resin 100g / L, and a mixture of citric acid and sodium fluoroborate with a mass fraction of 30g / L (since the patent does not disclose the specific mixing ratio, it is mixed according to a molar ratio of 1:1).

[0070] (2) Continuous impregnation: Select 50s Lyocell raw yarn, pour the working solution into the reaction tank 4, feed the yarn from the tension controller, unwind it through the unwinding device 5, and press it into the reaction tank 4 through the pressing roller. The yarn absorbs the working solution and is then squeezed by the polyester sandwich extrusion device 3 to control the liquid carry-over rate to 70%.

[0071] (3) Contact drying and baking: The yarn passes through a drying roller at 160°C and a baking roller at 200°C at a speed of 700m / min, and then is wound up.

[0072] To demonstrate the penetration of the antigen-fibrillating finishing working solution in the yarn cross-section of the embodiments and comparative examples of the present invention, undyed raw yarn was taken, and the process of the embodiments and comparative examples was completely replicated. The difference was that 2% dye was added to the working solution to facilitate observation of the penetration of the antigen-fibrillating finishing working solution in the yarn cross-section. Then, the yarn was cut open, and the cross-section of the yarn was observed using a handheld microscope. Figure 3 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Example 1; Figure 4 Microscopic image of the cross-section of yarn after antigen fibrillation treatment in Example 2; Figure 5 This is a microscopic image of the cross-section of the yarn after antigen fibrillation treatment in Example 3; Figures 3-5 It is known that the lyocell fiber produced using the process described in this invention forms a ring-shaped reaction zone only on the outer layer of the yarn, while the inner core layer of the yarn remains in an unreacted, natural state. Figure 6 This is a cross-sectional micrograph of the yarn after antigen fibrillation treatment in Example 4. The increased concentration of the auxiliary agent resulted in the complete penetration of the yarn. Figure 7 The image shows a cross-sectional microscopic image of the yarn after antigen fibrillation treatment in Comparative Example 1. The immersion time of the yarn in reaction tank 4 was increased, which also resulted in the complete penetration of the yarn. Figure 8The image shown is a cross-sectional microscope image of the yarn after antigen fibrillation treatment in Comparative Example 2. After adding the penetration enhancer, it deviates from the circumferential antigen fibrillation concept of this invention, and the Lyocell fiber is completely penetrated from the outer shell to the inner core. Figure 9 The image shown is a microscopic cross-section of yarn after antigen fibrillation treatment, which illustrates that the patented process aims for full penetration.

[0073] The yarns from the examples and comparative examples before and after treatment were woven into socks. Following standard AATCC 135, the socks were washed 5 times in a standard washing machine, removed, dried, and the pilling and fuzzing of the sock surface were observed.

[0074] Feel: The feel is evaluated by touch. ☆ indicates half a level and ★ indicates a level one level. Three people touch the feel and the average value is taken. The more stars, the better the feel.

[0075] The test results are shown in Table 1.

[0076] Table 1 Test Results

[0077]

[0078] The results showed that the untreated fabric was severely fibrillated on the surface after five washes; the fabric treated with surface antigen fibrillation did not show fibrillation after five washes, and the fabric surface was smooth and clean. Due to the cyclic antigen fibrillation treatment in Examples 1-3, the inner core layer maintained an unreacted natural state and had a soft hand feel.

[0079] The yarn strength before and after treatment in the examples and comparative examples was compared using a USTER IV high-speed tensile strength tester. The test results are shown in Table 2.

[0080] Table 2 Strength Test Results

[0081]

[0082] The results show that, due to the cyclic antigen fibrillation treatment in Examples 1-3, the core fiber remained in an unreacted natural state, thus preserving the mechanical properties of the lyocell fiber core.

Claims

1. A method for treating the surface antigens of lyocell yarn with fibrillation, characterized in that, Includes the following steps: (1) Preparation of working solution: Prepare working solution by mixing anionic antigen fibrillating agent, soda ash and water; (2) Single yarn antigen fiberization reaction: After the yarn is unwound, it passes through the reaction tank of the single yarn continuous antigen fiberization treatment device. The yarn surface reacts with the working liquid. After being squeezed by the extrusion device and dried by the rotating drum, it is wound into loose bobbin by the digital winding device. (3) Steaming and fixing the yarn: Use a steamer to fix the color of the treated loose yarn cones; (4) Post-treatment: Neutralize and wash the fixed yarn with water and dry it; In step (2), the time for the yarn to pass through the reaction tank is less than 0.1 seconds; =The anionic antigen fibrinolytic agent mentioned in step (1) is KR-6347; In step (1), the dosage of the anionic antigen fibrinolytic agent is 20-50 g / L, and the dosage of soda ash is 30-40 g / L. The color-fixing temperature in step (3) is 100-130℃, and the time is 10-30 min.

2. The method for treating the surface antigens of Lyocell yarn with fibrillation according to claim 1, characterized in that, The single yarn continuous antigen fiberization treatment device in step (2) consists of an unwinding device, a reaction tank, an extrusion device, a rotating drum, and a digital winding device.

3. The method for treating the surface antigens of Lyocell yarn with fibrillation according to claim 1, characterized in that, After the yarn leaves the reaction tank in step (2), the liquid carrying rate is controlled to be 90-100% by the extrusion device.

4. The method for treating the surface antigen fibrillation of Lyocell yarn according to claim 1, characterized in that, The density of the loose-knitted yarn in step (2) is 0.38-0.48 g / cm³. 3 .

5. The method for treating the surface antigens of Lyocell yarn with fibrillation according to claim 1, characterized in that, In step (2), the speed at which the yarn passes through the reaction tank is 600-800 m / min.

6. The method for treating the surface antigens of Lyocell yarn with fibrillation according to claim 1, characterized in that, The neutralization in step (4) involves adjusting the pH to 6-7 with acid.

7. The method for treating the surface antigen of Lyocell yarn with fibrillation according to claim 1, characterized in that, The temperature of the neutralization water wash in step (4) is 30-50℃, and the time is 5-20min.

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