A method for producing a wash-resistant stretch knit fabric

Abstract

The application discloses a preparation method of a washing-resistant elastic knitted fabric, and is characterized in that the method comprises the following steps: raw material selection, grey fabric weaving and dyeing and finishing process; the raw material selection selects (50-150) D / (48-144) F DTY low-elasticity yarn and (30-100) D / (24-72) F Sorona fiber to form a plying network yarn in parallel, thereby forming 100% polyester fiber; and the preparation method can effectively solve the problem of excessive shrinkage of the knitted fabric prepared from the Sorona fiber after high-temperature or multiple industrial washing, and the knitted fabric has soft hand feeling.

Description

Technical Field

[0001] This invention relates to the field of textile technology, and specifically to a method for preparing a washable elastic knitted fabric. Background Technology

[0002] Sorona fiber is polymerized from two main raw materials: propylene glycol (PDO) and purified terephthalic acid (PTA). PDO is the key ingredient, produced using a corn sugar fermentation method. Sorona fiber can be blended or interwoven with any natural or synthetic fiber, giving the fabric a soft hand feel, long-lasting shape retention, and comfortable stretch recovery, achieving a perfect combination of textile functionality and environmental friendliness. Furthermore, Sorona fiber has excellent eco-friendly and sustainable development characteristics. Fabrics developed by blending it with high-combed cotton fibers can achieve super-soft elasticity and excellent resilience and fatigue resistance that conventional knitted mercerized fabrics cannot reach. However, Sorona fabrics are in a shape-unstable state after weaving and dyeing, with potential shrinkage. If such fabrics are made into garments and then subjected to high-temperature industrial washing, they will change due to length shrinkage, and color difference and color fastness problems may occur during the dyeing and finishing process.

[0003] Existing methods to overcome the high shrinkage rate of Sorona fabric mainly involve conventional pre-shrinking followed by fabric setting to stabilize the shrinkage rate. However, this method is costly and can easily lead to a stiff hand feel. Furthermore, the yarns in knitted fabrics made from Sorona fibers move relatively freely, making them prone to arching after repeated use and exhibiting poor dimensional stability, further contributing to significant shrinkage after washing. Therefore, there is an urgent need to develop a washable elastic knitted fabric to address the aforementioned problems of high shrinkage and stiff hand feel in Sorona fabric. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing washable elastic knitted fabric, which can effectively solve the problem of excessive shrinkage of knitted fabrics made from Sorona fibers after high temperature or multiple industrial washings, and also provides a soft hand feel.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing a washable elastic knitted fabric includes: raw material selection, fabric weaving, and dyeing and finishing processes;

[0007] The raw material selection involves using (50-150)D / (48-144)F DTY low-elastic yarn and (30-100)D / (24-72)FSorona fiber to form a twisted network yarn, resulting in 100% polyester fiber.

[0008] The selection of raw materials is carried out on an air-coating machine;

[0009] The material of the (50-150)D / (48-144)F DTY low-elasticity yarn is polyester fiber;

[0010] The fabric is woven on a single-sided weft knitting machine with a yarn length of 12-20cm and 48-60 stitches.

[0011] In the fabric weaving process, the single-sided weft knitting machine has a gauge of 28-36 needles and an inch of 14-38 inches, and the fabric weaving process requires cylindrical roll fabric.

[0012] Preferably, in the fabric weaving process, one 100% conductive polyester fiber is added every 16-18 rows;

[0013] The method for preparing the 100% conductive polyester fiber is as follows: (50-150)D / (48-144)F DTY low elastic yarn, (30-100)D / (24-72)F Sorona fiber, and 40-60D polyester-based white conductive yarn are selected and connected in an air-coating machine to form a twisted network yarn, thereby forming 100% conductive polyester fiber.

[0014] The dyeing and finishing process includes: pretreatment, pre-shrinking, pre-setting, dyeing in the dyeing vat, drying, and setting.

[0015] The pretreatment process uses the following additives: refining agent AP-800 0.40-0.60 g / L, SEN refining emulsifier 0.90-1.10 g / L, hydrogen peroxide stabilizer ST 0.15-0.25 g / L, caustic soda 2.80-3.20 g / L, and H2O2 2.80-3.20 g / L.

[0016] The pretreatment temperature is 95-98℃, and the time is 20-40 min;

[0017] The pre-shrinking temperature is 80-100℃, and the vehicle speed is 10-20m / min;

[0018] Preferably, the pre-shrinking process is as follows: flat-width fabric feeding, widening and centering, overfeeding and needle insertion, steam humidification, stretching, needle removal, blanket pre-shrinking, centrifugal humidification, and flat-width fabric dropping; the mechanical speed of the pre-shrinking machine is 10-20 m / min, and a drying cylinder is used for heating, with the steam temperature controlled at 80-100℃.

[0019] The predetermined temperature is 140-150℃, and the vehicle speed is 20-30m / min;

[0020] Preferably, the pre-formed material first undergoes natural shrinkage for 20-30 hours, followed by shrinkage using high-temperature steam, with overfeed controlled at 10-15% and airflow at 80-90 m³ / h.3 / min;

[0021] The dyeing process involves a liquor ratio of 1:10-12, fabric input at 38-42℃, a temperature rise rate of 2-4℃ / min from 40℃ to 80℃, a temperature rise rate of 1-2℃ / min from 80℃ to 130℃, holding at 130℃ for 25-35 minutes, and a cooling rate of 1-3℃ / min from 130℃ to 80℃ before dyeing and exiting the dyeing vat.

[0022] The dyeing process involves opening the fabric to a width of 145-150cm.

[0023] Preferably, the dyeing process is carried out using a two-bath dyeing method.

[0024] Preferably, the drying temperature is 145-155℃ and the vehicle speed is 28-50m / min;

[0025] Preferably, the drying temperature is 1400-1500 RPM for both the upper and lower air volumes, with an overfeed of 90-95% for both the upper and lower volumes.

[0026] The shaping process involves pulling the fabric roll open to 165-170cm, overfeeding it 10-15% in length direction (both top and bottom), setting it at a temperature of 150-160℃, and operating at a speed of 15-20m / min.

[0027] Preferably, during the shaping process, 25-35 g / L of silicone-based softening agent HS-920 is added before shaping, and the mixture is dipped in a rolling mill at a speed of 15-20 m / min for a shaping time of 25-35 s.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] (1) The method for preparing the washable elastic knitted fabric of the present invention uses DTY low elastic yarn and Sorona fiber to form a ply network yarn on an air-wrapping machine. While achieving the elasticity of the fabric, it maintains the water shrinkage rate of the fabric and can withstand high temperature washing. It is suitable for hospital gowns.

[0030] (2) The method for preparing the washable elastic knitted fabric of the present invention has a finished weight of 100-300 gsm, preferably 155-230 gsm, and a shrinkage rate of T after 10 washes: -4.91 to -3.89 W: 5.13 to 5.63; a shrinkage rate of T after 100 industrial washes: -5.4 to -5.0 W: 4.74 to 5.84, an ironing shrinkage rate of T: -2.5 to -1.5 W: 0, no formaldehyde content detected, and a comfortable and soft hand feel;

[0031] (3) Existing technologies to overcome the large shrinkage rate of Sorona fabric mainly use conventional pre-shrinking to shape the fabric in order to stabilize the shrinkage rate. However, this method is costly and can easily lead to a stiff feel in the fabric. In this invention, a water washing pre-shrinking-shaping method is used to maximize the dimensional stability of the fabric and make it resistant to industrial washing. Detailed Implementation

[0032] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention are now described.

[0033] Example 1

[0034] A method for preparing a washable elastic knitted fabric, specifically comprising:

[0035] 1. Raw material selection: 150D / 96F DTY low elastic yarn and 100D / 72F Sorona fiber are selected and fused together on an air-coating machine to form a 100% polyester fiber;

[0036] The 150D / 96F DTY low-elasticity yarn is made of polyester fiber;

[0037] 2. Fabric weaving: The fabric is woven on a 28-needle 30-inch single-sided weft knitting machine with a yarn length of 12cm / 60 needles. The fabric weaving requires a cylindrical roll to avoid problems such as unraveling and curling of the selvage.

[0038] 3. Dyeing and finishing process: including pretreatment, pre-shrinking, pre-setting, dyeing in vat, drying, and setting;

[0039] (1) Pretreatment: The pretreatment aids include: refining agent AP-800 0.50g / L, SEN refining emulsifier 1.00g / L, hydrogen peroxide stabilizer ST 0.20g / L, caustic soda 3.00g / L, H2O2 3.00g / L, the pretreatment temperature is 98℃, and the treatment time is 25min;

[0040] (2) Pre-shrinkage: temperature is 80℃, vehicle speed is 20m / min;

[0041] (3) Pre-set type: temperature is 150℃, vehicle speed is 20m / min;

[0042] (4) Dyeing in the vat: The liquor ratio is 1:10. The fabric is fed into the vat at 40℃. The temperature rise rate from 40℃ to 80℃ is 2℃ / min, and the temperature rise rate from 80℃ to 130℃ is 1℃ / min to avoid color spots and streaks. The fabric is kept warm for 25 minutes. The temperature drop rate from 130℃ to 80℃ is 1℃ / min to avoid chicken foot patterns on the fabric surface. After dyeing, the fabric is removed from the vat and the width after opening is 150cm. The weight of the fabric after opening is 170g / m². 2;

[0043] (5) Drying: The vehicle speed is 28m / min, the temperature is 145℃, the upper air volume is 1400RPM, the lower air volume is 1400RPM, the upper overfeed is 95%, the lower overfeed is 93%, the temperature is 150℃, and the vehicle speed is 30m / min.

[0044] (6) Shaping: Pull the pre-treated fabric roll open to 165cm, overfeed 15% in length direction (top and bottom combined), and set the weight to 156g / m. 2 The temperature during the shaping process is 150℃, and the vehicle speed is 20m / min.

[0045] The final properties of the fabric prepared in this embodiment are: 230gsm×165cm, shrinkage rate after 10 washes (T: -4.91W: 5.13), shrinkage rate after 100 industrial washes (T: -5.1W: 5.34), shrinkage rate after ironing (T: -1.5W: 0), formaldehyde content not detected, and a comfortable and soft feel.

[0046] Example 2

[0047] A method for preparing a washable elastic knitted fabric, specifically comprising:

[0048] 1. Raw material selection: 100D / 144F DTY low elastic yarn and 50D / 48F Sorona fiber are selected and fused together on an air-coating machine to form a 100% polyester fiber;

[0049] 100D / 144F DTY low-elasticity yarn, 50D / 48F Sorona fiber and 50D polyester-based white conductive yarn are selected and connected in an air-coating machine to form a twisted network yarn, forming 100% conductive polyester fiber.

[0050] 2. Fabric weaving: The fabric is woven on a 32-needle 34-inch single-sided weft knitting machine with a yarn length of 15cm / 50 needles. One 100% conductive polyester fiber is added every 17 rows. The fabric weaving requires cylindrical roll fabric to avoid problems such as fabric edge unraveling and curling.

[0051] 3. Dyeing and finishing process: including pretreatment, pre-shrinking, pre-setting, dyeing in vat, drying, and setting;

[0052] (1) Pretreatment: The pretreatment aids include refining agent AP-800 0.50g / L, SEN refining emulsifier 1.00g / L, hydrogen peroxide stabilizer ST 0.20g / L, caustic soda 3.00g / L, H2O2 3.00g / L, the pretreatment temperature is 98℃, and the treatment time is 30min;

[0053] (2) Pre-shrinkage: temperature is 100℃, vehicle speed is 20m / min;

[0054] (3) Pre-set type: temperature is 150℃, vehicle speed is 30m / min;

[0055] (4) Dyeing in the vat: The bath ratio is 1:12. The fabric is fed in at 40℃. The temperature rise rate from 40℃ to 80℃ is 4℃ / min. The temperature rise rate from 80℃ to 130℃ is 2℃ / min to avoid color spots and streaks. The fabric is kept warm for 35 minutes. The temperature drop rate from 130℃ to 80℃ is 3℃ / min to avoid chicken foot patterns on the fabric surface. After dyeing, the fabric is taken out of the vat and removed from the machine. The width after opening is 150cm. The weight of the fabric after opening is 170g / m².

[0056] (5) Drying: The vehicle speed is 32m / min, the temperature is 155℃, the upper air volume is 1500RPM, the lower air volume is 1500RPM, the upper overfeed is 95%, and the lower overfeed is 93%.

[0057] (6) Shaping: Pull the pre-treated fabric roll open to 170cm, overfeed 15% in length direction, set the weight at 160g / ㎡, set the temperature at 150℃, and set the speed at 30m / min.

[0058] The final properties of the fabric in this embodiment are: 155gsm×168cm, shrinkage rate after 10 washes (T: -3.89 W: 5.63), shrinkage rate after 100 industrial washes (T: -5.4 W: 5.84), shrinkage rate after ironing (T: -2.5 W: 0), formaldehyde content not detected, and a comfortable and soft feel.

[0059] Example 3

[0060] A method for preparing a washable elastic knitted fabric, specifically comprising:

[0061] 1. Raw material selection: 75D / 72F DTY low elastic yarn and 50D / 24F Sorona fiber are selected and fused together on an air-coating machine to form a 100% polyester fiber;

[0062] 2. Fabric weaving: The fabric is woven on a 36-needle 38-inch single-sided weft knitting machine with a yarn length of 20cm / 48 needles. The fabric weaving requires a cylindrical roll to avoid problems such as unraveling and curling of the selvage.

[0063] 3. Dyeing and finishing process: including pretreatment, pre-shrinking, pre-setting, dyeing in vat, drying, and setting;

[0064] (1) Pretreatment: The pretreatment aids include: refining agent AP-800 0.50g / L, SEN refining emulsifier 1.00g / L, hydrogen peroxide stabilizer ST 0.20g / L, caustic soda 3.00g / L, H2O2 3.00g / L, the pretreatment temperature is 98℃, and the treatment time is 30min;

[0065] (2) Pre-shrinking: The pre-shrinking process is as follows: flat fabric feeding - widening and centering - overfeeding and needle mounting - steam humidification - stretching - needle removal - blanket pre-shrinking - centrifugal humidification - flat fabric unloading;

[0066] The machine speed during pre-shrinking is 45 m / min, and heating is achieved using a drying cylinder. The steam temperature is controlled at 140℃. The width of the product exiting the machine is increased by 3 cm as required, and the gram-to-mass ratio is reduced by 5 g / m. 2 The finished product width is controlled at 155±2cm, and the weight is (210±2)g / m². 2 The shrinkage rate is 3% in the longitudinal direction and 3% in the transverse direction. The finished fabric has a smooth, flat surface, strong drape, and a smooth feel.

[0067] (3) Pre-sizing: First, allow natural shrinkage for 24 hours, then shrink through high-temperature steam to ensure the bio-based Sorona fibers are fully shaped and to guarantee the elasticity and elastic recovery of the fabric. The pre-sizing process formula and conditions are: overfeed 10%, air volume 90m³ / h. 3 The setting speed is 20 m / min, and the temperature is 150℃.

[0068] (4) Dyeing in the vat: The two-bath dyeing method is adopted. The bath ratio is 1:12. The fabric is fed into the vat at 40℃. The temperature rise rate from 40℃ to 80℃ is 2℃ / min, and the temperature rise rate from 80℃ to 130℃ is 1℃ / min to avoid color spots and streaks. The fabric is held at 130℃ for 30 minutes, and the temperature drop rate from 130℃ to 80℃ is 2℃ / min to avoid chicken foot patterns on the fabric surface. After dyeing, the fabric is removed from the vat and the width after opening is 150cm. The weight of the fabric after opening is 170g / m². 2 ;

[0069] (5) Drying: The drying temperature is 150℃ and the vehicle speed is 50m / min;

[0070] (6) Setting: Add 30g / L of silicone softening agent HS-920 before setting, dip and roll on a roller at a speed of 15m / min, and heat set on a circular knitting machine at a speed of 15m / min and a temperature of 160℃ for 30s.

[0071] The test data of the finished fabric after finishing are as follows: 170gsm×155cm, shrinkage rate after 10 washes: T: -3.91 W: 5.13, shrinkage rate after 100 industrial washes: T: -5.0 W: 4.74, ironing shrinkage rate: T: -1.6 W: 0, formaldehyde content not detected, and the fabric feels comfortable and soft.

[0072] Comparative Example 1

[0073] The same method for preparing washable elastic knitted fabric as in Example 3 was used, except that the pre-shrinking process in step (2) of the dyeing and finishing process in step 3 was changed to: sewing the end of the bad fabric—expansion and overfeeding—steaming and humidifying—second heat setting—exhaust cooling—fabric unloading and folding.

[0074] The test data of the prepared washable elastic knitted fabric are as follows: 170gsm×155cm, shrinkage rate after 10 washes: T: -4.53 W: 7.56, shrinkage rate after 100 washes: T: -9.94 W: 8.07, ironing shrinkage rate: T: -4 W: 0, and the fabric has a soft hand feel.

[0075] Unless otherwise stated, all percentages used in this invention are mass percentages.

[0076] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a washable elastic knitted fabric, characterized in that, include: Raw material selection, fabric weaving, dyeing and finishing processes; The raw material selection involves using (50-150)D / (48-144)F DTY low-elastic yarn and (30-100)D / (24-72)FSorona fiber to form a twisted network yarn, resulting in 100% polyester fiber. The selection of raw materials is carried out on an air-coating machine; The material of the (50-150)D / (48-144)F DTY low-elasticity yarn is polyester fiber; The fabric is woven on a single-sided weft knitting machine with a yarn length of 12-20cm and 48-60 stitches. In the fabric weaving process, the single-sided weft knitting machine has a gauge of 28-36 needles and an inch of 14-38 inches, and the fabric weaving process requires cylindrical roll fabric. The dyeing and finishing process includes: pretreatment, pre-shrinking, pre-setting, dyeing in the dyeing vat, drying, and setting. The pretreatment process uses the following additives: refining agent AP-800 0.40-0.60 g / L, SEN refining emulsifier 0.90-1.10 g / L, hydrogen peroxide stabilizer ST 0.15-0.25 g / L, caustic soda 2.80-3.20 g / L, and H2O2 2.80-3.20 g / L. The pretreatment temperature is 95-98℃, and the time is 20-40 min; The pre-shrinking process is as follows: flat fabric feeding - widening and centering - superfeeding and needle insertion - steam humidification - stretching - needle removal - blanket pre-shrinking - centrifugal humidification - flat fabric unloading; the mechanical speed of the pre-shrinking machine is 40-50m / min, and a drying cylinder is used for heating, with the steam temperature controlled at 130-140℃. The predetermined shape first undergoes natural shrinkage for 20-30 hours, followed by high-temperature steam shrinkage, with overfeed controlled at 10-15% and air volume at 80-90 m³ / h. 3 / min; The predetermined temperature is 140-150℃, and the vehicle speed is 20-30m / min; The dyeing process involves a liquor ratio of 1:10-12, feeding the fabric at 38-42℃, raising the temperature from 40℃ to 80℃ at a rate of 2-4℃ / min, raising the temperature from 80℃ to 130℃ at a rate of 1-2℃ / min, holding at 130℃ for 25-35 minutes, and lowering the temperature from 130℃ to 80℃ at a rate of 1-3℃ / min. After dyeing, the fabric exits the dyeing vat and is unrolled, with a width of 145-150cm. The drying temperature is 145-155℃, and the vehicle speed is 28-50m / min; The shaping process involves pulling the fabric roll open to 165-170cm, overfeeding it by 10-15% in length (both top and bottom), setting it at a temperature of 150-160℃, and operating at a speed of 15-20m / min.

2. The method for preparing the washable elastic knitted fabric according to claim 1, characterized in that, In the fabric weaving process, one 100% conductive polyester fiber is added every 16-18 rows. The method for preparing the 100% conductive polyester fiber is as follows: (50-150)D / (48-144)F DTY low elastic yarn, (30-100)D / (24-72)F Sorona fiber, and 40-60D polyester-based white conductive yarn are selected and connected in an air-coating machine to form a twisted network yarn, thereby forming 100% conductive polyester fiber.