Secondary shaping finishing and dyeing method for solving edge-center difference of spandex fabric
By performing two predetermined tensile processes and other process processing on the four-sided elastic fabric, the problem of poor sides of the four-sided elastic fabric is solved, uniform color and stable size are achieved, and the overall quality of the fabric is improved.
Patent Information
- Application Number
- CN202510646385.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-20
- Publication Date
- 2025-08-15
AI Technical Summary
During the dyeing and finishing process, the dyeing depths of the four-sided elastic fabrics are different due to uneven stress on spandex elastic yarns, resulting in different color differences (differences between the edges) and the dimensional stability becomes worse when the setting temperature rises.
Two predetermined processes of tensile are adopted, and the speed is 35~45m/min and 25~35m/min respectively. Combined with the shrinkage, tension-free desizing, refining and dyeing, a small number of stretched fibers are arranged in uniform molecules by multiple times to ensure uniform color and no color difference.
The color uniformity and dimensional stability of the four-sided elastic fabric is achieved, which reduces the color difference between the edges, meets the width requirements of the finished product and avoids shrinkage, and improves the overall quality of the fabric.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of textile fabrics, and in particular to a secondary shaping and finishing method for solving edge and center differences of four-sided stretch fabrics. Background Art
[0002] The spandex yarn used in four-way stretch fabrics is subjected to high-intensity stretching at high temperatures during dyeing and finishing. This results in uneven dyeing depths at the edges and center of the fabric due to uneven stress on the left, center, and right sides, leading to color variations, often referred to as edge-to-center color variation. The study "The Effect of Presetting Process on Color Variation in Polyamide / Spandex Stretch Knitted Fabrics" states that if the setting process is not sufficiently relaxed and the setting temperature is too high, color variations can occur at the ends and left, center, and right sides. This color variation can be mitigated by lowering the setting temperature. However, low setting temperatures fail to stabilize the fabric's shape, resulting in substandard creases and width. This necessitates higher setting temperatures to achieve these requirements, causing the edge-to-center color variation to reappear and impairing the dimensional stability of the finished product. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to provide a secondary shaping and finishing method for solving the edge difference of four-sided stretch fabric and having good dimensional stability.
[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a secondary setting and dyeing method for solving the edge difference of four-sided stretch fabric, comprising the following steps: the fabric is sequentially subjected to a shrinking process, a tension-free desizing process, a first tentering and predetermined process, a second tentering and predetermined process, and a dyeing process; The temperature of the first tentering predetermined process is 195-205°C and the speed is 35-45m / min; The temperature of the second tentering predetermined process is 200-208° C., and the speed is 25-35 m / min.
[0005] The beneficial effect of the present invention is that the secondary setting and dyeing method of the present invention carries out two tentering predetermined processes. The tentering predetermined processes of small amounts and multiple times can meet the width requirements of the finished product while uniformly stretching the transverse fibers in stages in the width direction, so that the same molecular arrangement is maintained on the left, middle and right sides at the microscopic level, the size and shape are consistent, and the degree of heat is consistent, thereby obtaining a fabric with uniform color and no color difference. DETAILED DESCRIPTION
[0006] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the implementation methods.
[0007] A secondary shaping and dyeing method for solving the edge difference of four-way stretch fabrics, comprising the following steps: the fabrics are sequentially subjected to a quenching process, a tension-free desizing process, a first tentering and pre-setting process, a second tentering and pre-setting process, and a dyeing process; The temperature of the first tentering process is 195~205℃ and the speed is 35~45m / min; The temperature of the second tentering predetermined process is 200-208° C., and the speed is 25-35 m / min.
[0008] From the above description, it can be seen that the beneficial effects of the present invention are: the dyeing method of the present invention first shrinks the fabric so that it shrinks without constraint, thereby improving dimensional stability; then tension-free desizing is performed to remove the attached sizing and reduce the dimensional instability, shrinkage and other problems of the fabric caused by tension changes during subsequent processing; followed by two tentering predetermined processes, the tentering can meet the width requirements of the finished product and will not shrink after dyeing vat processing. Through a small amount of multiple tentering predetermined processes, the spandex is stretched steadily and evenly, so that the transverse fibers in the width direction can be stretched evenly in stages, and the transverse fibers maintain the same molecular arrangement on the left, middle and right sides at the microscopic level, with consistent size and shape, and consistent heat exposure, thereby obtaining a fabric with uniform color and no color difference.
[0009] The first stretch is set at a lower temperature and faster speed, which can initially set the shape and eliminate the internal stress of the fabric; the second stretch is set at a higher temperature and slower speed, which can improve dimensional stability, achieve the required width and reduce the risk of color difference.
[0010] Furthermore, the temperature of the first tentering predetermined process is lower than the temperature of the second tentering predetermined process.
[0011] Furthermore, the stretching in the first predetermined stretching process is greater than the stretching in the second predetermined stretching process.
[0012] From the above description, it can be seen that if the stretching in the first stretching predetermined process is too large, the probability of the edge-center difference will increase, making the dyeing of the cloth unstable.
[0013] Furthermore, the stretching in the first predetermined stretching process is 30-45% of the full stretching, and the second predetermined stretching process stretches the width to the required width of the finished product.
[0014] From the above description, it can be seen that the smaller the single stretching rate, the smaller the force on the fiber and the smaller the stretching degree, so that the shape and size difference between the middle and the two sides of the fiber is not much, reducing the color difference between the edges.
[0015] Furthermore, the temperature of the reduction process is 85-95°C, the speed is 30-40 m / min, and the overfeed is 1.8-2.2%.
[0016] From the above description, it can be seen that overfeeding during milling causes the fabric to shrink in a relaxed state, reducing internal stress, avoiding width narrowing, and reducing appearance defects such as wrinkles and waves.
[0017] Furthermore, the temperature of the tension-free desizing is 90-100° C., and the speed is 25-35 m / min.
[0018] Furthermore, a refining step is included between the second tentering step and the dyeing step.
[0019] Furthermore, in the refining process, 1.5-2.5 g / L of soda ash, 0.8-1.2 g / L of degreaser, 4-6 g / L of hydrogen peroxide and 1-2 g / L of stabilizer are added.
[0020] From the above description, we can see that soda ash and degreasers are added in the refining process to remove grease; hydrogen peroxide is added to remove impurities on the fiber surface and improve the gloss and feel of the fabric; and stabilizers are added to reduce the oxidative damage of hydrogen peroxide to the fiber and protect the strength and performance of the fiber.
[0021] Furthermore, the dyeing process also includes a setting process.
[0022] Furthermore, the temperature of the forming process is 145~155°C and the speed is 35~45m / min.
[0023] From the above description, it can be seen that a lower temperature is used when the finished product is set to prevent the dye inside the fiber from migrating to the surface and sublimating, causing color difference and avoiding unqualified shrinkage.
[0024] The first embodiment of the present invention is a secondary setting and dyeing method for solving the edge difference of four-sided stretch fabric, which comprises the following steps: S1. Weaving: The grey fabric is composed of 27.4wt% white semi-gloss 75D / 72F polyester environmentally friendly micro-mesh DTY + 40D spandex, 45.2wt% white semi-gloss 150D / 288F polyester environmentally friendly micro-mesh DTY + 40D spandex, and 27.4wt% white semi-gloss 150D / 288F polyester environmentally friendly low-elastic light mesh DTY, with a gram weight of 200g / m 2 , width 125cm, weft density 116T.
[0025] S2: Shrinking process: A shrinking machine is used with a temperature of 90°C, a speed of 35m / min, and an overfeed of 2%. After shrinking, the width of the grey cloth is 116cm and the weft density is 110T (110 threads / inch).
[0026] S3. Tension-free desizing process: a tension-free desizing machine is used with a temperature of 95°C and a speed of 30m / min. After tension-free desizing, the width of the grey cloth is 116cm and the weft density is 115T.
[0027] S4. The first stentering process: using a Monforts stentering machine, the temperature is 200 ° C, the speed is 40m / min, the stentering is 40% of the full stenting, and after the first stentering, the width of the grey cloth is 129.6cm and the weft density is 109T.
[0028] S5. Second stentering process: using Monforts stentering machine, the temperature is 205℃, the speed is 30m / min, the width of the grey cloth after the second stentering is 150cm, and the weft density is 115T.
[0029] S6. Refining process: It is carried out in an Ithaca overflow dyeing machine. The grey cloth is put into water, and 2g / L of soda ash, 1g / L of degreaser AFN, 5g / L of hydrogen peroxide and 1.5g / L of stabilizer (Stabilizer EL-SF from Zhejiang Yutai Dyeing and Chemical Technology Co., Ltd.) are added. The temperature is kept at 85°C for 20 minutes.
[0030] S7. Dyeing process: The dyeing process is carried out in an Ithaca overflow dyeing machine with a cloth weight to water weight ratio of 1:12 and a cylinder capacity of 85%. The temperature is first raised to 80°C at a heating rate of 1.5°C / min, then raised to 95°C at a heating rate of 0.5°C / min and held for 10 minutes, then raised to 105°C at a heating rate of 0.5°C / min and held for 10 minutes, then raised to 135°C at a heating rate of 1°C / min and held for 45 minutes, then cooled to 75°C at a cooling rate of 1°C / min, drained, dehydrated, spread and dried. The materials added for dyeing are shown in Table 1.
[0031] Table 1
[0032] S8, setting process: using Monforts stenter setting machine, temperature is 150℃, speed is 40m / min.
[0033] Comparative Example 1 of the present invention is: The only difference between Comparative Example 1 and Example 1 is that the tentering is not performed during the first reservation, and the tentering is performed to a width of 150 cm for the grey cloth during the second reservation.
[0034] Comparative Example 2 of the present invention is: The only difference between Comparative Example 2 and Example 1 is that the first tentering reservation is not performed.
[0035] The color difference between the edge and the center of the finished fabrics of Example 1, Comparative Example 1 and Comparative Example 2 was observed. The observation results are shown in Table 2.
[0036] Table 2
[0037] The color difference between the edge and the center is expressed by DE, and DE>0.6% indicates that there is color difference.
[0038] The second embodiment of the present invention is: The only difference between Example 2 of the present invention and Example 1 is that: the temperature of the reduction process is 85°C, the speed is 30m / min, and the overfeed is 1.8%; the temperature of the tension-free desizing process is 90°C, the speed is 25m / min; the temperature of the first tentering predetermined process is 195°C, the speed is 35m / min, the tentering is 30% of the full tentering, and the width of the grey cloth after the first tentering is predetermined is 126.2cm; the temperature of the second tentering predetermined process is 200°C, the speed is 25m / min, and the width of the grey cloth after the second tentering is predetermined is 150cm; 1.5g / L of soda ash, 0.8g / L of degreaser, 4g / L of hydrogen peroxide and 1g / L of stabilizer are added in the refining process; the temperature of the setting process is 145°C and the speed is 35m / min.
[0039] The third embodiment of the present invention is: The only difference between Example 3 of the present invention and Example 1 is that: the temperature of the reduction process is 95°C, the speed is 40m / min, and the overfeed is 2.2%; the temperature of the tension-free desizing process is 100°C, the speed is 35m / min; the temperature of the first tentering predetermined process is 205°C, the speed is 45m / min, the tentering is 45% of the full tentering, and the width of the grey cloth after the first tentering is predetermined is 131.3cm; the temperature of the second tentering predetermined process is 208°C, the speed is 35m / min, and the width of the grey cloth after the second tentering is predetermined is 150cm; 2.5g / L of soda ash, 1.2g / L of degreaser, 6g / L of hydrogen peroxide and 2g / L of stabilizer are added in the refining process; the temperature of the setting process is 155°C and the speed is 45m / min.
[0040] In summary, the secondary shaping and dyeing method provided by the present invention to solve the problem of edge and center color difference of four-way stretch fabrics is to stretch the spandex yarn in small amounts multiple times through two stretching times, so that the stress is evenly distributed in all directions and it is not easy to produce edge and center color difference. The width can be fixed normally and will not shrink after dyeing vat processing. At the same time, the use of a lower temperature during the finishing process can effectively prevent the edge and center color difference (step difference) and unqualified shrinkage of the fabric.
[0041] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the description of the present invention, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A secondary shaping and finishing method for solving the edge difference of four-sided stretch fabrics, characterized in that: The following steps are involved: The fabric goes through the shrinking process, tension-free desizing process, first tentering process, second tentering process and dyeing process in sequence; The temperature of the first tentering predetermined process is 195-205°C and the speed is 35-45m / min; The temperature of the second tentering predetermined process is 200-208° C., and the speed is 25-35 m / min.
2. The secondary shaping and finishing method for solving the edge difference of four-way stretch fabric according to claim 1, characterized in that: The temperature of the first tentering step is lower than the temperature of the second tentering step.
3. The secondary shaping and finishing method for solving the edge difference of four-way stretch fabric according to claim 1, characterized in that: The tentering in the first tentering predetermined process is greater than the tentering in the second tentering predetermined process.
4. The secondary shaping and finishing method for solving the edge difference of four-way stretch fabric according to claim 1, characterized in that: The stretching of the first predetermined stretching process is 30-45% of the full stretching.
5. The secondary shaping and finishing method for solving the edge difference of four-way stretch fabric according to claim 1 is characterized in that: The temperature of the reduction process is 85-95° C., the speed is 30-40 m / min, and the overfeed is 1.8-2.2%.
6. The secondary shaping and finishing method for solving the edge difference of four-way stretch fabric according to claim 1, characterized in that: The temperature of the tension-free desizing is 90-100° C., and the speed is 25-35 m / min.
7. The secondary setting and dyeing method for solving the edge difference of four-way stretch fabric according to claim 1 is characterized in that: A refining step is further included between the second tentering step and the dyeing step.
8. The secondary setting and dyeing method for solving the edge difference of four-way stretch fabric according to claim 7, characterized in that: In the refining process, 1.5-2.5 g / L of soda ash, 0.8-1.2 g / L of degreaser, 4-6 g / L of hydrogen peroxide and 1-2 g / L of stabilizer are added.
9. The secondary setting and dyeing method for solving the edge difference of four-way stretch fabric according to claim 1, characterized in that: The dyeing process also includes a setting process.
10. The secondary setting and dyeing method for solving the edge difference of four-way stretch fabric according to claim 9, characterized in that: The temperature of the forming process is 145-155° C., and the speed is 35-45 m / min.