Dyeing and finishing process for modal / cotton-polyester blended air layer fabric

Abstract

The invention provides a dyeing and finishing process for a modal / cotton-polyester blended air layer fabric. The dyeing and finishing process comprises the following steps: splitting the pretreated modal / cotton-polyester blended air layer fabric to obtain a to-be-dyed fabric, then dyeing the to-be-dyed fabric by a one-bath one-step method, and finally performing post-setting to finish dyeing and finishing. The one-bath one-step method is adopted for dyeing, and proper pretreatment and after-treatment are combined, so that the average water required in the dyeing and finishing process of the blended fabric is saved by about 30%, the wastewater discharge is averagely reduced by about 1000 tons or more per year, the staining fastness of the fabric exceeds grade 4, the dry rubbing fastness of the fabric reaches grade 4, the wet rubbing fastness reaches grade 4, and the soaping fastness reaches grade 3 or more; the conventional production requirements are met.

Description

Technical Field

[0001] The invention relates to the technical field of textiles, in particular to a dyeing and finishing process for modal / polyester-cotton blended air layer fabrics. Background Art

[0002] Modal, a regenerated fiber, is highly sought after for its softness, smoothness, moisture absorption, breathability, and excellent drape. Combining Modal with polyester and cotton, and creating an air layer structure, effectively integrates the advantages of multiple fibers, giving the fabric excellent warmth retention, loft, breathability, moisture conductivity, and next-to-skin comfort. It is widely used in thermal underwear, home wear, sportswear, and other fields. However, these fabrics contain fiber components with very different properties. Modal and cotton are hydrophilic cellulose fibers, while polyester is a hydrophobic synthetic fiber. These significant differences in chemical properties pose significant challenges to fabric dyeing and finishing.

[0003] To meet the dyeing requirements of different fibers, existing dyeing processes typically use a two-bath, two-step process. However, this process is lengthy, consumes significant amounts of water resources, produces high levels of wastewater, and repeatedly heats the fabric, brittle it, and affects the fabric's feel (e.g., stiffening and fuzzing). The one-bath, one-step process is difficult to achieve for modal / polyester / cotton blends. For complex fabrics with air gaps, efficient, high-quality one-bath dyeing is even more challenging due to poor dye compatibility and conflicting dyeing conditions.

[0004] Therefore, there is an urgent need to develop a dyeing process that can significantly shorten the process, greatly reduce water consumption, reduce wastewater discharge, ensure the color fastness of dyed fabrics, and is suitable for modal / polyester-cotton blended air layer fabrics. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention provides a dyeing and finishing process for modal / polyester / cotton blended air-layer fabrics. This process utilizes pH gradient control (from an initial pH of 4-4.5 to an alkaline transition) and coordinated temperature control (115°C medium-high temperature dyeing combined with 80°C reactive dyeing) to achieve simultaneous dyeing of the two-component fibers. Sequential step-by-step dye addition and intermediate water washing and isolation techniques avoid dye compatibility issues. A strong acid fiber opening pretreatment (pH 1.8-2.2) enhances air-layer permeability, while precise 1°C / min temperature control ensures dyeing uniformity. The innovative "pre-setting, intermediate setting, and return setting" triple setting process effectively protects the fiber structure. This process reduces water consumption during the dyeing and finishing of blended fabrics by approximately 30%, reducing wastewater discharge by over 1,000 tons annually. Furthermore, the fabrics exhibit staining fastness exceeding Grade 4, dry rubbing fastness reaching Grade 4, wet rubbing fastness reaching Grade 4, and soaping fastness exceeding Grade 3, all meeting conventional production requirements. This process achieves efficient and environmentally friendly dyeing and finishing of blended air-layer fabrics, addressing the challenges identified in the aforementioned background art.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: According to a first aspect of the present invention, a dyeing and finishing process for a modal / polyester-cotton blended air layer fabric is provided, comprising the following steps: opening the pre-treated modal / polyester-cotton blended air layer fabric to obtain a fabric to be dyed, dyeing the fabric to be dyed using a one-bath one-step method, and finally performing post-setting to complete the dyeing and finishing.

[0007] Preferably, the specific steps of the one-bath one-step dyeing method are: (1) placing the fabric to be dyed in a vat for deacidification and washing, then adjusting the pH value in the vat to 4-4.5, adjusting the temperature to 80°C, and keeping warm for 5-10 minutes; (2) Add disperse dye into the vat under the conditions of step (1), complete the addition within 25-30 minutes and keep it warm for 5-10 minutes, then heat it to 115-120°C at a heating rate of 1°C / min and keep it warm for 30-40 minutes. After dyeing is completed, cool it down to 80°C at a cooling rate of 1°C / min and keep it warm for 5-10 minutes. Finally, cool it down to 60°C and drain the dye solution in the vat. At the same time, pour 60°C running water into the vat for 10 minutes. (3) Add reactive dyes into the tank, complete the feeding within 25-30 minutes and keep warm for 10 minutes, then add sodium sulfate into the tank and keep warm for 10 minutes, and finally add soda ash in batches, keeping warm for 10 minutes between adjacent batches, and keep warm for 30-40 minutes after the feeding is completed; (4) After completing the reactive dye dyeing, drain the water and inject 60℃ running water into the tank for 10 minutes. Finally, add soap powder and heat it to 80℃ at a rate of 1℃ / min for soap washing for 20~30 minutes. Finally, drain the water and rinse it with running water.

[0008] In the one-bath one-step process, the disperse dyes are: Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Ultramarine T-2 0.63.

[0009] The reactive dyes are red M 8B 2.5%, yellow M-3RE 0.75%, and blue M-8B 0.75%.

[0010] Preferably, in step (2), the concentration of the disperse dye is 1-3%.

[0011] Preferably, in step (3), the concentration of the reactive dye is 2-6%; The amount of sodium sulfate added is 5-10% of the fabric to be dyed; The feeding amount of the soda ash is 10-20% of the fabric to be dyed.

[0012] Preferably, the pre-finishing comprises turning over the cloth, steaming and pre-setting in sequence.

[0013] Preferably, the steaming temperature is 90-95°C, and the pre-setting temperature is 190-210°C.

[0014] Preferably, the fiber opening is performed by acid treatment with a sulfuric acid solution, the pH of the sulfuric acid solution is 1.8-2.2, the temperature of the acid treatment is 110-115° C., and the time is 30-40 minutes.

[0015] Preferably, the post-finishing includes center setting, yarn washing, air beating and back setting.

[0016] Preferably, the predetermined temperature is 180-190°C; The temperature of the yarn washing is 80-85°C; The air beating time is 5 to 10 minutes; The temperature of the back setting is 180-190°C.

[0017] The present invention provides a dyeing and finishing process for modal / polyester / cotton blended air layer fabrics, which has the following beneficial effects: This solution provides a dyeing and finishing process for modal / polyester-cotton blended air-layer fabrics. By adopting a one-bath, one-step dyeing process, combined with precise pH and temperature control, phased feeding and efficient finishing, it can achieve 30% water savings and reduce annual wastewater emissions by over 1,000 tons. At the same time, it ensures the fabric's dry / wet friction fastness ≥ Grade 3-4 and soap fastness ≥ Grade 3, significantly improving production efficiency and environmental protection, and using large-scale green manufacturing. DETAILED DESCRIPTION

[0018] In order to better illustrate the content of the present invention, a detailed description is given below in conjunction with specific embodiments.

[0019] Example 1 A dyeing and finishing process for modal / polyester-cotton blended air layer fabric comprises the following steps: Pretreatment: The Modal / polyester-cotton blended air-layer fabric is first turned over, then steamed at 92°C, and finally pre-set at 200°C; Fiber opening treatment: the pre-treated modal / polyester-cotton blended air layer fabric was placed in a sulfuric acid solution with a pH value of 2 for 35 minutes to obtain a fabric to be dyed; One-bath one-step dyeing: Place the fabric to be dyed in a vat for deacidification and washing, adjust the pH value in the vat to 4, adjust the temperature to 80℃, keep warm for 10 minutes, then add 2% disperse dye (Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Dark Blue T-2 0.63) into the vat, complete the addition within 25 minutes and keep warm for 8 minutes, first increase the temperature to 115℃ at a rate of 1℃ / min, keep warm for 35 minutes, after dyeing is completed, cool it down to 80℃ at a rate of 1℃ / min, keep warm for 5 minutes, then cool it down to 60℃ and drain the dye liquor in the vat, at the same time pour 60℃ running water into the vat for 10 minutes, then add 4% reactive dye (Red M 8B 2.5%, Yellow M-3RE 0.75%, Blue M-8B 0.75%), complete the feeding within 25 minutes and keep warm for 10 minutes, then add 6% sodium sulfate, keep warm for 10 minutes, add 15% soda ash in 3 batches, keep warm for 10 minutes between adjacent batches, keep warm for 30 minutes after the feeding is completed, after the reactive dye dyeing is completed, drain the dye liquor, and inject 60℃ running water into the tank to rinse for 10 minutes, finally add 2% soap powder, heat up to 80℃ at a rate of 1℃ / min, wash with soap for 25 minutes, and add running water to rinse while draining; Finishing: The dyed fabric was first fixed at 185°C, then yarn washed at 82°C, and then air-beaten for 8 minutes and then back-set at 185°C to obtain the dyed fabric.

[0020] Example 2 A dyeing and finishing process for modal / polyester-cotton blended air layer fabric comprises the following steps: Pretreatment: The Modal / polyester-cotton blended air-layer fabric is first turned over, then steamed at 92°C, and finally pre-set at 200°C; Fiber opening treatment: the pre-treated modal / polyester-cotton blended air layer fabric was placed in a sulfuric acid solution with a pH value of 2 for 35 minutes to obtain a fabric to be dyed; One-bath one-step dyeing: Place the fabric to be dyed in a vat for deacidification and washing, adjust the pH value in the vat to 4, adjust the temperature to 80℃, keep warm for 10 minutes, then add 2% disperse dyes (Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Dark Blue T-2 0.63) into the vat, complete the addition within 25 minutes and keep warm for 8 minutes, first increase the temperature to 120℃ at a rate of 1℃ / min, keep warm for 35 minutes, after dyeing is completed, reduce the temperature to 80℃ at a rate of 1℃ / min, keep warm for 5 minutes, then cool to 60℃ and drain the dye liquor in the vat, at the same time pour 60℃ running water into the vat for 10 minutes, then add 4% reactive dyes (Red M 8B 2.5%, Yellow M-3RE 0.75%, Blue M-8B 0.75%), complete the feeding within 25 minutes and keep warm for 10 minutes, then add 6% sodium sulfate, keep warm for 10 minutes, add 15% soda ash in 3 batches, keep warm for 10 minutes between adjacent batches, keep warm for 30 minutes after the feeding is completed, after the reactive dye dyeing is completed, drain the dye liquor, and inject 60℃ running water into the tank to rinse for 10 minutes, finally add 2% soap powder, heat up to 80℃ at a rate of 1℃ / min, wash with soap for 25 minutes, and add running water to rinse while draining; Finishing: The dyed fabric was first fixed at 185°C, then yarn washed at 82°C, and then air-beaten for 8 minutes and then back-set at 185°C to obtain the dyed fabric.

[0021] Example 3 A dyeing and finishing process for modal / polyester-cotton blended air layer fabric comprises the following steps: Pretreatment: The Modal / polyester-cotton blended air-layer fabric is first turned over, then steamed at 92°C, and finally pre-set at 200°C; Fiber opening treatment: the pre-treated modal / polyester-cotton blended air layer fabric was placed in a sulfuric acid solution with a pH value of 1.8 for 40 minutes to obtain a fabric to be dyed; One-bath one-step dyeing: Place the fabric to be dyed in a vat for deacidification and washing, adjust the pH value in the vat to 4, adjust the temperature to 80℃, keep warm for 10 minutes, then add 2% disperse dyes (Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Dark Blue T-2 0.63) into the vat, complete the addition within 25 minutes and keep warm for 8 minutes, first increase the temperature to 120℃ at a rate of 1℃ / min, keep warm for 35 minutes, after dyeing is completed, reduce the temperature to 80℃ at a rate of 1℃ / min, keep warm for 5 minutes, then cool to 60℃ and drain the dye liquor in the vat, at the same time pour 60℃ running water into the vat for 10 minutes, then add 4% reactive dyes (Red M 8B 2.5%, Yellow M-3RE 0.75%, Blue M-8B 0.75%), complete the feeding within 25 minutes and keep warm for 10 minutes, then add 6% sodium sulfate, keep warm for 10 minutes, add 15% soda ash in 3 batches, keep warm for 10 minutes between adjacent batches, keep warm for 30 minutes after the feeding is completed, after the reactive dye dyeing is completed, drain the dye liquor, and inject 60℃ running water into the tank to rinse for 10 minutes, finally add 2% soap powder, heat up to 80℃ at a rate of 1℃ / min, wash with soap for 25 minutes, and add running water to rinse while draining; Finishing: The dyed fabric was first fixed at 185°C, then yarn washed at 82°C, and then air-beaten for 8 minutes and then back-set at 185°C to obtain the dyed fabric.

[0022] Comparative Example 1 Pretreatment: The Modal / polyester-cotton blended air-layer fabric is first turned over, then steamed at 92°C, and finally pre-set at 200°C; The first step is disperse dye dyeing: the pre-treated fabric is placed in a vat for deacidification and water washing, the pH value in the vat is adjusted to 5, the temperature is adjusted to 50°C, and the temperature is kept for 10 minutes. Then 2% disperse dye (Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Dark Blue T-2 0.63) is added to the vat. The addition is completed within 30 minutes and the temperature is kept for 10 minutes. The temperature is first raised to 115°C at a rate of 1°C / min and kept for 45 minutes. After dyeing is completed, the temperature is lowered to 80°C at a rate of 1°C / min. After keeping for 5 minutes, the temperature is lowered to 60°C and the dye solution in the vat is discharged. At the same time, 60°C running water is poured into the vat for rinsing for 15 minutes. Reduction cleaning: add 2g / L sodium hypochlorite and 3g / L caustic soda into the tank, heat it to 80℃ at a rate of 1℃ / min for 20min, then add 60℃ running water to rinse for 10min while draining the water; Step 2: Dyeing with reactive dyes: Adjust the pH value in the vat to 7 and the temperature to 30°C. Add 4% reactive dyes (2.5% red M8B, 0.75% yellow M-3RE, and 0.75% blue M-8B) into the vat. Add the materials within 15 minutes and keep them warm for 15 minutes. Then add 8% sodium sulfate and keep them warm for 30 minutes. Then add 18% soda ash in three batches. Keep them warm for 15 minutes between each batch. After adding the materials, keep them warm for 60 minutes. After dyeing with reactive dyes, drain the dye liquor and inject cold water into the vat to rinse continuously until it is neutral. Soaping: Finally, add 2% soap powder and heat the temperature to 95°C at a rate of 1°C / min. After soaping for 30 minutes, add 80°C hot water and rinse for 10 minutes while draining the water. Then rinse with cold water. Finishing: The dyed fabric was first fixed at 185°C, then yarn washed at 82°C, and then air-beaten for 8 minutes and then back-set at 185°C to obtain the dyed fabric.

[0023] Comparative Example 2 Pretreatment: The Modal / polyester-cotton blended air-layer fabric is first turned over, then steamed at 92°C, and finally pre-set at 200°C; The first step is disperse dye dyeing: the pre-treated fabric is placed in a vat for deacidification and water washing, the pH value in the vat is adjusted to 5, the temperature is adjusted to 50℃, and the temperature is kept for 10 minutes. Then 2% disperse dye (Disperse Yellow T-1 0.35%, Disperse Orange T-2 1.02%, Disperse Dark Blue T-2 0.63) is added to the vat. The addition is completed within 30 minutes and the temperature is kept for 10 minutes. The temperature is first raised to 120℃ at a rate of 1℃ / min and kept for 35 minutes (the original process is 45 minutes). After dyeing is completed, the temperature is lowered to 80℃ at a rate of 1℃ / min. After keeping for 5 minutes, the temperature is lowered to 60℃ and the dye solution in the vat is discharged. At the same time, 60℃ running water is poured into the vat for rinsing for 15 minutes. Reduction cleaning: add 2g / L sodium hypochlorite and 3g / L caustic soda into the tank, heat it to 80℃ at a rate of 1℃ / min for 20min, then add 60℃ running water to rinse for 10min while draining the water; Step 2: Dyeing with reactive dyes: Adjust the pH value in the vat to 7 and the temperature to 30°C. Add 4% reactive dyes (2.5% red M 8B, 0.75% yellow M-3RE, 0.75% blue M-8B) into the vat. Add the materials within 15 minutes and keep them warm for 15 minutes. Then add 8% sodium sulfate and keep them warm for 30 minutes. Then add 18% soda ash in three batches. Keep them warm for 15 minutes between each batch. After adding the materials, keep them warm for 60 minutes. After dyeing with reactive dyes, drain the dye liquor and inject cold water into the vat to rinse it until it is neutral. Soap washing: Finally, add 2% soap powder, heat up to 95℃ at a rate of 1℃ / min, and soap for 30 minutes. Then, add 80℃ hot water to rinse for 10 minutes while draining the water, and then rinse with cold water. Finishing: The dyed fabric was first fixed at 185°C, then yarn washed at 82°C, and then air-beaten for 8 minutes and then back-set at 185°C to obtain the dyed fabric.

[0024] The water consumption, dry rubbing fastness, wet rubbing fastness, soaping fastness, staining fastness and production cycle of Examples 1 to 3 and Comparative Examples 1 to 2 were tested respectively, and the results are shown in Table 1.

[0025] Table 1

[0026] As shown in Table 1, and through comparative test data, Example 1 (pH = 2 fiber opening treatment + 115°C one-bath, one-step process) demonstrates significant advantages across all key performance indicators: minimal water consumption, optimal wet rubbing fastness, and the shortest production cycle. All color fastness indicators achieved Grade 4 or above, achieving a perfect balance between dyeing performance and resource efficiency. In contrast, increasing the fiber opening acidity in Example 3 or the dyeing temperature in Example 2 both resulted in fiber damage, which in turn increased the wet rubbing fastness. Furthermore, the traditional two-bath process in Comparative Example 1 suffers from the inherent drawbacks of high water consumption and prolonged dyeing time. By precisely controlling the fiber opening pH = 2 and the dyeing temperature at 115°C, Example 1 achieves an optimal synergy of quality, efficiency, and environmental performance in the dyeing of modal / polyester-cotton blended fabrics, making it an optimal solution for industrial production.

[0027] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A dyeing and finishing process for modal / polyester-cotton blended air layer fabric, characterized by: The following steps are involved: The pre-treated modal / polyester-cotton blended air layer fabric is opened to obtain a fabric to be dyed, and then the fabric to be dyed is dyed in one bath and one step, and finally post-set to complete the dyeing and finishing.

2. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 1, characterized in that: The specific steps of the one-bath one-step dyeing process are: (1) placing the fabric to be dyed in a vat for deacidification and washing, then adjusting the pH value in the vat to 4-4.5, adjusting the temperature to 80°C, and keeping warm for 5-10 minutes; (2) Add disperse dye into the vat under the conditions of step (1), complete the addition within 25-30 minutes and keep it warm for 5-10 minutes, then heat it to 115-120°C at a heating rate of 1°C / min and keep it warm for 30-40 minutes. After dyeing is completed, cool it down to 80°C at a cooling rate of 1°C / min and keep it warm for 5-10 minutes. Finally, cool it down to 60°C and drain the dye solution in the vat. At the same time, pour 60°C running water into the vat for 10 minutes. (3) Add reactive dyes into the tank, complete the feeding within 25-30 minutes and keep warm for 10 minutes, then add sodium sulfate into the tank and keep warm for 10 minutes, and finally add soda ash in batches, keeping warm for 10 minutes between adjacent batches, and keep warm for 30-40 minutes after the feeding is completed; (4) After completing the reactive dye dyeing, drain the water and inject 60℃ running water into the tank for 10 minutes. Finally, add soap powder and heat it to 80℃ at a rate of 1℃ / min for soap washing for 20~30 minutes. Finally, drain the water and rinse it with running water.

3. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 2, characterized in that: In step (2), the concentration of the disperse dye is 1-3%.

4. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 2, characterized in that: In step (3), the concentration of the reactive dye is 2-6%; The amount of sodium sulfate added is 5-10% of the fabric to be dyed; The feeding amount of the soda ash is 10-20% of the fabric to be dyed.

5. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 1, characterized in that: The pre-finishing comprises turning over the cloth, steaming and pre-setting in sequence.

6. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 5, characterized in that: The steaming temperature is 90-95°C, and the pre-setting temperature is 190-210°C.

7. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 1, characterized in that: The fiber opening is performed by acid treatment with a sulfuric acid solution, the pH of the sulfuric acid solution is 1.8-2.2, the temperature of the acid treatment is 110-115° C., and the time is 30-40 minutes.

8. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 1, characterized in that: The post-finishing process includes center setting, yarn washing, air beating and back setting.

9. The dyeing and finishing process for modal / polyester-cotton blended air layer fabric according to claim 8, characterized in that: The set temperature is 180~190℃; The temperature of the yarn washing is 80-85°C; The air beating time is 5 to 10 minutes; The temperature of the back setting is 180-190°C.

Images