Method for overflow dyeing of knitted fabric after weak alkaline mercerization

Abstract

This invention belongs to the field of dyeing and processing technology, specifically relating to an overflow dyeing method for knitted fabrics after mercerization with a light alkali. The overflow dyeing method for knitted fabrics after mercerization with a light alkali involves dyeing knitted fabrics woven from cotton yarns of 50 count and above, including the following steps: singeing, mercerizing, oxygen bleaching, dyeing, soaping, color fixing, and polishing. The polishing conditions are: pH 5-6, polishing temperature 50-60℃, polishing time 50-80 min, and polishing enzyme dosage 0.2-0.5 wt.%. This invention addresses the shortcomings of existing commercially available knitted fabrics, such as low density, unstable shrinkage density dimensions, and poor stiffness, by providing an overflow dyeing method for knitted fabrics after mercerization with a light alkali, resulting in uniform dyeing, no color spots or stains, and fabric surface less prone to abrasion.

Description

Technical Field

[0001] This invention belongs to the field of dyeing and processing technology, specifically relating to an overflow dyeing method for knitted fabrics after mercerization with light alkali. Background Technology

[0002] Currently, most knitted fabrics on the market that undergo overflow dyeing are either directly dyed without mercerizing or mercerized knitted fabrics with a count below 50 and a low density, used for making polo shirts and T-shirts. If used for shirts or other formal wear, they simply cannot meet the requirements of being crisp, soft, and smooth.

[0003] Traditional knitted fabrics lack the crispness, dimensional stability, and soft, smooth feel required for making shirts. However, to meet these requirements, the fabric must have a high density and undergo special pre-treatment before dyeing. This high density and mercerizing process can lead to problems such as fabric abrasions, uneven dyeing, color variations, and stains during the subsequent dyeing process.

[0004] Patent CN103981742A proposes a dyeing method for cotton knitted fabrics, including: (1) pretreatment and bleaching of the cotton knitted fabric; (2) polishing treatment using de-hairing enzyme water; (3) dyeing at room temperature using a cationic modifier; and (4) dyeing with dye solution. This dyeing method for cotton knitted fabrics improves the dye's adsorption effect on the fabric, enhances the smoothness of the fabric surface, and provides advantages such as good dyeing effect, high durability, and long service life.

[0005] Patent CN104846659A discloses a dyeing method for knitted fabric blanks, which includes: soaking, heating, washing, soaping, drying, and testing. This method effectively improves the dyeing quality of knitted fabric blanks, requires fewer types of chemicals in the dyeing process, is simple, and effectively improves the color fastness and K / S value of the finished knitted fabric blanks.

[0006] Patent CN110699977A proposes a dyeing method combining overflow dyeing and long-cycle dyeing for cotton and viscose-polyester fabrics. The method includes the following steps: A) Turning the cotton or viscose-polyester grey fabric over to obtain product A; B) Pre-treating product A with alkali and oxygen, followed by cold stacking to obtain product B; C) Performing tight bleaching on product B to obtain product C; D) Singeing product C to obtain product D; E) Pre-shaping product D to obtain product E; F) Performing high-temperature, high-pressure overflow dyeing on product E with disperse dyes to obtain product F; G) Washing product F to obtain product G; H) Drying product G to obtain product H; I) Performing long-cycle dyeing on product H with reactive dyes to obtain product I; J) Finishing product I to obtain product J; K) Pre-shrinking product J to obtain product K; L) Inspecting and packaging product K to obtain the finished product. Its characteristics include high dyeing efficiency, small batch variation, good fastness, small weight loss, and good elasticity of the dyed fabric.

[0007] Patent CN112030423A proposes a high-temperature, high-pressure overflow dyeing system and an environmentally friendly dyeing method. This system utilizes a water rinsing tank, including a main body with a first upper support beam fixedly mounted on its upper end. A first drive motor is fixedly mounted on the upper end of the first upper support beam, and an inner cleaning rod is mounted on the drive end of the first drive motor. An external auxiliary dyeing tank, including a main body with a temperature heating wall fixedly mounted on its exterior, also has a first upper support beam fixedly mounted on its upper end. A rotating sealing door is rotatably mounted on the surface of the first upper support beam. This system solves the problem that when dyeing different fabrics, a certain amount of dyeing may be incomplete, requiring subsequent touch-up dyeing, which affects the dyeing quality of the fabric and negatively impacts the manufacturing enterprise. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing commercially available knitted fabrics, such as low density, unstable shrinkage density, and poor stiffness, by providing an overflow dyeing method for knitted fabrics after light alkali mercerizing. This method results in uniform dyeing, no color spots or stains, and the fabric surface is less prone to abrasion.

[0009] The overflow dyeing method for knitted fabrics after mercerization with light alkali described in this invention dyes knitted fabrics woven from cotton yarns of 50 count and above, including the following steps: singeing, mercerizing, oxygen bleaching, dyeing, soaping, color fixing, and polishing.

[0010] In this invention, there are no requirements on the structure and specifications of the knitted fabric used for dyeing; it can be any structure and specification.

[0011] In this invention, the singeing process conditions are: machine speed 70-80 m / min, double-sided direct singeing. The purpose of singeing is to remove the fuzz from the fabric surface and make it smooth and clean.

[0012] In this invention, the mercerizing process conditions are: machine speed 25–35 m / min, low alkali concentration 15–26 Baume degrees. Mercerizing can give the fabric a certain stiffness and good hand feel, combining the advantages of woven fabrics.

[0013] In this invention, the oxygen bleaching process conditions are as follows: the treatment solution formula is: anti-wrinkle agent 1-4 g / L, softener 1-3 g / L, chelating agent 0.3-1.5 g / L, refining agent 1-2 g / L, H2O2 stabilizer 1-3 g / L, NaOH 2-5 g / L, H2O2 5-9 g / L, neutralizing acid 0.5-1 g / L, and deoxygenating enzyme 0.1-0.25 g / L; the treatment temperature is 105℃, and the treatment time is 30-50 min.

[0014] The preferred anti-wrinkle agent for bath use is JES, an anti-wrinkle agent from Qingdao Ounon Industry & Trade Co., Ltd.

[0015] The preferred bath softener is C-652 from Suzhou Liansheng Co., Ltd.

[0016] The preferred chelating agent is SQ-B from Lurui Additives Co., Ltd.

[0017] The preferred refining agent is refining agent 1155 from Demei Chemical Co., Ltd.

[0018] The preferred H2O2 stabilizer is hydrogen peroxide stabilizer 266 from Nantong Aor Industry & Trade Co., Ltd.

[0019] The neutralizing acid is preferably PH-N from Lurui Additives Co., Ltd.

[0020] The preferred deoxygenase is EZ-B from Lurui Additives Co., Ltd.

[0021] In this invention, the dyeing process conditions are as follows: the dyeing solution includes reactive dyes, sodium sulfate, and soda ash; the dyeing temperature is 50–90°C.

[0022] During the dyeing process, different reactive dyes are selected for different colors according to customer requirements, and different amounts of sodium sulfate and soda ash are added according to the concentration of different reactive dyes. Generally, the amount of sodium sulfate is between 10 and 100 g / L, and the amount of soda ash is between 10 and 20 g / L.

[0023] In this invention, the soaping process conditions are as follows: soaping temperature 80-105℃, soaping time 10-20min, and soaping agent dosage 1-2g / L.

[0024] The preferred soaping agent is WOLR soaping agent from Lurui Additives Co., Ltd.

[0025] The purpose of soaping is to ensure the effective color development and color fastness of the fabric. Depending on the concentration of different reactive dyes, soaping is performed 1 to 3 times.

[0026] In this invention, the conditions for the color-fixing process are: color-fixing temperature 45-55℃, color-fixing time 15-30 min, and color-fixing agent dosage of 2-5% of the weight of the knitted fabric.

[0027] The fixing agent is preferably FARLR, a fixing agent from Lurui Additives Co., Ltd.

[0028] In this invention, the polishing process conditions are as follows: textile acid is added to adjust the pH value to 5-6, then polishing enzyme is added, and polishing is performed at 50-60°C for 50-80 minutes.

[0029] The preferred textile acid is HAC-P65 from Nanjing Yushi Textile Co., Ltd.

[0030] The polishing enzyme is preferably polishing enzyme D300 from Suzhou Liansheng Co., Ltd.

[0031] Color fastening and polishing can further enhance the fabric's durability and gloss.

[0032] Preferably, a bath softener is added in both the soaping and polishing processes, and the bath softener is preferably C-652 from Suzhou Liansheng Co., Ltd.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] (1) This invention uses high-count, high-density knitted fabric and mercerizes the fabric, which breaks through the defects of conventional knitted fabric such as looseness, instability, and poor stiffness. The fabric surface is soft, smooth, and stiff, and has good luster, hand feel and wrinkle resistance. The produced products have a smooth and flat fabric surface, and have the characteristics of woven fabric.

[0035] (2) This invention effectively solves problems such as fabric abrasion, uneven dyeing, and color spots in the dyeing process by optimizing the dyeing process feeding method and polishing process. Detailed Implementation

[0036] The present invention will be further described below with reference to the embodiments. Unless otherwise specified, the raw materials used in the embodiments are all commercially available conventional raw materials; unless otherwise specified, the process methods used in the embodiments are all conventional methods in the art.

[0037] The following is a description of some of the raw materials used in the examples:

[0038] Anti-wrinkle agent for bath use: JES anti-wrinkle agent from Qingdao Ounuoen Industry & Trade Co., Ltd.;

[0039] Bath softener: C-652 from Suzhou Liansheng Co., Ltd.;

[0040] Chelating agent: SQ-B chelating agent from Lurui Additives Co., Ltd.;

[0041] Refining agent: Refining agent 1155 from Demei Chemical Co., Ltd.;

[0042] H2O2 stabilizer: Hydrogen peroxide stabilizer 266 from Nantong Aor Industry & Trade Co., Ltd.;

[0043] Neutralizing acid: PH-N neutralizing acid from Lurui Additives Co., Ltd.;

[0044] Oxygenase: EZ-B oxygenase from Lurui Additives Co., Ltd.;

[0045] Leveling agent: LA-R leveling agent from Lurui Auxiliary Agents Co., Ltd.;

[0046] Soap detergent: WOLR soap detergent from Lurui Additives Co., Ltd.;

[0047] Fixing agent: FARLR fixing agent from Lurui Additives Co., Ltd.;

[0048] Textile acid: HAC-P65 textile acid from Nanjing Yushi Textile Co., Ltd.;

[0049] Polishing enzyme: Polishing enzyme D300 from Suzhou Liansheng Co., Ltd.

[0050] Example 1

[0051] Cotton yarn of 60 count * 60 count is woven into a cotton jersey knitted fabric with a width of 156cm, a weight of 190g, and a specification of 156*190*61*041060L*041060L. The fabric is then dyed using the overflow dyeing method of this invention, including the following steps:

[0052] (1) Singeing: The machine speed is 70m / min, and the two sides are singed to make the fabric surface smooth and clean.

[0053] (2) Mercerizing: at a speed of 35m / min, mercerizing with a low alkali concentration of 26 Baume degrees gives the fabric a certain stiffness and good hand feel, making it combine the advantages of woven fabrics.

[0054] (3) Oxygen bleaching: The treatment solution formula is as follows: anti-wrinkle agent 3g / L, softener 2g / L, chelating agent 0.5g / L, refining agent 1g / L, H2O2 stabilizer 2g / L, NaOH 3g / L, H2O2 8g / L, neutralizing acid 0.75g / L, and deoxygenating enzyme 0.2g / L; the fabric is immersed in the treatment solution at 50℃, heated to 105℃ at a rate of 2.5℃ / min and held for 40min, cooled to 60℃ at a rate of 2℃ / min and then discharged, the fabric is re-immersed in water at 60℃ and held for 10min and then discharged, and then re-immersed in water at 50℃ and held for 20min and then discharged to remove H2O2.

[0055] (4) Dyeing: When the fabric is immersed in water at 50℃, first add 2g / L of bath softener, then add 2g / L of leveling agent and reactive dye (neutral dyes from Kyungin Korea: BLUEHL: 0.0041%, R3BL: 0.122%, Y3RL: 0.332%, percentages are percentages of the dyeing solution mass). Continue adding for 25 minutes, maintain for 10 minutes, then add 10% of the total amount of sodium sulfate (total sodium sulfate is 30g / L). Continue adding for 25 minutes, maintain for 5 minutes, then add 20% of the total amount of sodium sulfate. Continue adding for 20 minutes, maintain for 5 minutes, then add 70% of the total amount of sodium sulfate. Continuously add water, then raise the temperature to 60℃ at a rate of 1℃ / min and hold for 10 minutes. Add 10% of the total amount of soda ash (total soda ash is 15g / L), and continue adding for 25 minutes. Hold for 5 minutes, then add 20% of the total amount of soda ash, and continue adding for 20 minutes. Hold for 5 minutes, then add the remaining 70% of the total amount of soda ash, and continue adding for 20 minutes. Hold for 40 minutes and then drain. Re-immerse the fabric in water at 60℃ and hold for 10 minutes, then drain. Re-immerse the fabric in water, add 1g / L of neutralizing acid for pickling, hold at 50℃ for 10 minutes, and then drain. The acid pickling and neutralization ensures a suitable pH value, laying the foundation for effective soaping later.

[0056] (5) Soap washing: After the fabric is immersed in water, add 1g / L bath softener and 2g / L soap washing agent in sequence, keep at 95℃ for 15min and then discharge; repeat the same process twice; re-immerse the fabric in water at 60℃ for 10min and then discharge.

[0057] (6) Color fixing: After the fabric is immersed in water, add 3% of the weight of the knitted fabric as a color fixing agent, keep it at 50℃ for 20 minutes and then discharge it.

[0058] (7) Polishing: After the fabric is immersed in water, add 1g / L bath softener and 0.5g / L acetic acid in sequence to adjust the pH value to 5-6. Then add polishing enzyme at 0.3% of the total volume of the knitted fabric to be dyed. Keep at 55℃ for 60min and then discharge. The fabric is re-immersed in water at 90℃ for 6min and then discharged for inactivation. It is then immersed in room temperature water again for 5min and then discharged.

[0059] The dyed cotton knitted fabric is soft, smooth, crisp, and has good luster, hand feel, and wrinkle resistance. The fabric surface was not scratched during the dyeing process, and the dyeing was even.

[0060] Example 2

[0061] Cotton yarn of 50 count * 50 count is woven into a cotton jersey knitted fabric with a width of 165cm, a weight of 185g, and a size of 165*185*64*041050L*041050L. The fabric is then dyed using the overflow dyeing method of this invention, including the following steps:

[0062] (1) Singeing: The machine speed is 80m / min, and the two sides are singed to make the fabric surface smooth and clean.

[0063] (2) Mercerizing: at a speed of 30m / min, mercerizing with a low alkali concentration of 18 Baume degrees gives the fabric a certain stiffness and good hand feel, making it combine the advantages of woven fabrics.

[0064] (3) Oxygen bleaching: The treatment solution formula is as follows: anti-wrinkle agent 3g / L, softener 0.5g / L, chelating agent 0.5g / L, refining agent 1g / L, H2O2 stabilizer 2g / L, NaOH 3g / L, H2O2 8g / L, neutralizing acid 0.75g / L, and deoxygenating enzyme 0.2g / L; the fabric is immersed in the treatment solution at 50℃, heated to 105℃ at a rate of 2.5℃ / min and held for 40min, cooled to 60℃ at a rate of 2℃ / min and then discharged, the fabric is re-immersed in water at 60℃ and held for 10min and then discharged, and then re-immersed in water at 50℃ and held for 20min and then discharged to remove H2O2.

[0065] (4) Dyeing: When the fabric is immersed in water at 50℃, first add 2g / L of bath softener, then add 2g / L of leveling agent and reactive dye (Clariant high-temperature dyes NXGN: 6.3%, RX6BN: 0.63%, YX4RN: 1.03%, percentages are percentages of the dyeing solution mass). Add the dye in a curved manner over 25 minutes. After maintaining this position for 10 minutes, add 80g / L of 10% sodium sulfate, again in a curved manner over 15 minutes. After maintaining this position for 5 minutes, add 20% sodium sulfate, again in a curved manner over 15 minutes. After maintaining this position for 5 minutes, add 30% sodium sulfate, again in a curved manner over 15 minutes. After maintaining this position for 5 minutes, add 40% sodium sulfate, again in a curved manner over 15 minutes. After adding the dyes, increase the temperature by 1℃ / min. The temperature is increased to 60℃ at a rate of 100°C and held for 10 minutes. Then, 10% soda ash (20 g / L) is added in a curved manner over 25 minutes. After holding for 5 minutes, 20% soda ash is added in a curved manner over 20 minutes. After holding for 5 minutes, 30% soda ash is added in a curved manner over 20 minutes. After holding for 5 minutes, 40% soda ash is added in a curved manner over 20 minutes. After holding for 10 minutes, the temperature is increased to 90℃ at a rate of 1℃ / min and held for 50 minutes before being discharged. The fabric is then re-immersed in water at 60℃ and held for 10 minutes before being discharged. The fabric is then re-immersed in water with 3 g / L of neutralizing acid (PH-N) for acid washing at 50℃ and held for 10 minutes before being discharged. The acid washing and neutralization ensures a suitable pH value, laying the foundation for effective soap washing later.

[0066] The following steps are required: Add sodium sulfate continuously over 25 minutes, maintain for 10 minutes, then add 10% of the total sodium sulfate (total sodium sulfate dosage is 30 g / L). Continue adding sodium sulfate continuously over 25 minutes, maintain for 5 minutes, then add another 20% of the total sodium sulfate. Continue adding sodium sulfate continuously over 20 minutes, maintain for 5 minutes, then add the remaining 70% of the total sodium sulfate. Continue adding sodium sulfate continuously over 20 minutes. After adding sodium sulfate, raise the temperature to 60°C at a rate of 1°C / min, maintain for 10 minutes, then add 10% of the total soda ash (total soda ash dosage is...). Add 15g / L of soda ash continuously for 25 minutes, maintain for 5 minutes, then add 20% of the total soda ash, continue adding for 20 minutes, maintain for 5 minutes, then add the remaining 70% of the total soda ash, continue adding for 20 minutes, maintain for 40 minutes, then drain. Re-immerse the fabric in water at 60℃ for 10 minutes, then drain. Re-immerse the fabric in water, add 1g / L of neutralizing acid PH-N for acid washing, maintain at 50℃ for 10 minutes, then drain. Acid washing and neutralization ensure a suitable pH value to lay the foundation for effective soap washing later.

[0067] (5) Soap washing: After the fabric is immersed in water, add 1g / L bath softener and 2g / L soap washing agent in sequence, keep at 95℃ for 15min and then discharge; repeat the same process three times; immerse the fabric in water again at 60℃ for 10min and then discharge.

[0068] (6) Fixing: When the fabric is immersed in water, add 5% of the total volume of the knitted fabric to be dyed in a curved ratio within 10 minutes. Heat to 50℃ and maintain for 20 minutes before discharging.

[0069] (7) Polishing: After the fabric is immersed in water, add 1g / L bath softener and 0.5g / L acetic acid in sequence to adjust the pH value to 5-6. Then add polishing enzyme at 0.3% of the total volume of the knitted fabric to be dyed. Keep at 55℃ for 60min and then discharge. The fabric is re-immersed in water at 90℃ for 6min and then discharged for inactivation. It is then immersed in room temperature water again for 5min and then discharged.

[0070] The dyed cotton knitted fabric is soft, smooth, crisp, and has good luster, hand feel, and wrinkle resistance. The fabric surface was not scratched during the dyeing process, and the dyeing was even.

[0071] Comparative Example 1

[0072] The only difference between this comparative example and Example 1 is that the cotton jersey knitted fabric was replaced with 40*40 count cotton yarn. The fabric surface was not scratched during the dyeing process, and the dyeing was uniform. However, the dyed cotton jersey knitted fabric was not soft enough and had low stiffness.

[0073] Comparative Example 2

[0074] The only difference between this comparative example and Example 1 is that the cotton knitted fabric is not polished. The fabric surface is easily scratched during the dyeing process, and the dyed cotton knitted fabric has an insufficiently smooth feel, poor wrinkle resistance, and low stiffness.

[0075] Comparative Example 3

[0076] The only difference between this comparative example and Example 1 is that the reactive dye, raw starch, and soda ash are added in a single step during the dyeing process. The dyed cotton and wool knitted fabrics exhibited uneven dyeing and color variations.

Claims

1. An overflow dyeing method for knitted fabrics after mercerization with light alkali, characterized in that: The dyeing process for knitted fabrics made of cotton yarn with a count of 50 or higher includes the following steps: singeing, mercerizing, oxygen bleaching, dyeing, soaping, color fixing, and polishing. Mercerizing process conditions: machine speed 25~35m / min, low alkali concentration 15~26 Baume mercerizing; Polishing process conditions: pH value 5~6, polishing temperature 50~60℃, polishing time 50~80min, polishing enzyme dosage 0.2~0.5wt.% of the weight of the knitted fabric to be dyed; Oxygen bleaching process conditions: The treatment solution formula is as follows: anti-wrinkle agent 1~4g / L, softener 1~3g / L, chelating agent 0.3~1.5g / L, refining agent 1~2g / L, H2O2 stabilizer 1~3g / L, NaOH 2~5g / L, H2O2 5~9g / L, neutralizing acid 0.5~1g / L, deoxygenating enzyme 0.1~0.25g / L; treatment temperature 105℃, treatment time 30~50min; In the dyeing process, sodium sulfate and soda ash are added in batches.

2. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Singeing process conditions: machine speed 70~80m / min, double-sided direct singeing.

3. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Dyeing process conditions: The dyeing solution includes reactive dyes, sodium sulfate and soda ash; the dyeing temperature is 50~90℃.

4. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 3, characterized in that: In the staining solution, the amount of sodium sulfate is 10~100g / L and the amount of soda ash is 10~20g / L.

5. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Soap washing process conditions: soap washing temperature 80~105℃, soap washing time 10~20min, soap washing agent dosage 1~2g / L.

6. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Fixing process conditions: Fixing temperature 45~55℃, fixing time 15~30min, fixing agent dosage is 2~5wt.% of the weight of the knitted fabric to be dyed.

7. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Acetic acid is used to adjust the pH value during polishing.

8. The overflow dyeing method for knitted fabric after mercerization with light alkali according to claim 1, characterized in that: Bath softener is added during both the soaping and polishing processes.