Ethanol salt-free dyeing and washing method of reactive dye

Abstract

The invention belongs to the technical field of textile dyeing, and particularly relates to an ethanol salt-free dyeing and washing method of reactive dye. The method comprises the following steps: S1, putting the cotton fabric into an aqueous solution of an alkaline substance and a cationic modifier for padding; s2, putting the cotton fabric into dye liquor of reactive dye, heating to a certain temperature, and keeping the temperature for a period of time; s3, after dyeing for a period of time, adding a color fixing agent into the dye liquor, and keeping the same temperature for a period of time; s4, putting the cotton fabric subjected to color fixation into a solution containing a surfactant for washing, and then drying to obtain a finished product. On the premise of keeping the color fastness and the dyeing effect, salt-free dyeing can be realized, the water consumption in the textile dyeing and washing process is reduced, the influence on the environment is reduced, and the sustainable development of the textile industry is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of textile dyeing, and in particular relates to an ethanol salt-free dyeing and washing method of a reactive dye. Background Art

[0002] At present, most of the media of printing and dyeing processes at home and abroad use water as the dispersion medium of dyes. The problems of high water consumption and high salt consumption have become an important issue that needs to be solved urgently in the textile printing and dyeing industry. According to the traditional printing and dyeing process, 100 to 200 tons of water are needed to process 1 ton of textiles, of which 80% to 90% eventually become wastewater. Traditional dyeing of cotton fabrics usually uses reactive dyes and dyes with water as the medium. Unfixed dyes and non-degradable inorganic salts will be discharged with dyeing wastewater, causing water and soil pollution and damage to the ecological environment. Therefore, it is urgent to develop a dyeing technology that can reduce the use of water and salt from the source.

[0003] Patent No. CN 110258141 A discloses a method for improving the fixation rate of active dyes in an alcohol organic solvent-water system, wherein a pre-dyed cotton textile is modified by using an alkali solution and a cationic modifier in the same bath, and then the pre-dyed cotton textile is directly dyed in an alcohol organic solvent-water system, and the cotton textile after dyeing is cooled to room temperature, and then washed, soaped, washed and dried to obtain a finished product. The alcohol organic solvent is one of ethanol, isopropanol or glycerol, which reduces the amount of water and salt, and the alcohol organic solvent can be recycled, reducing waste liquid discharge, but the post-treatment after the dyeing and fixation process of this method still requires a large amount of water to wash away the residual floating color on the cotton fiber, which also causes a large amount of waste water.

[0004] Chinese patent number CN 105064078 A, the invention name is a non-aqueous medium dyeing and soaping method of a reactive dye. The method first places the fiber in an aqueous solution of an alkaline substance for swelling and then drying, then mixes the dried cotton fabric with a reactive dye and a good solvent for the reactive dye, heats up, adds a poor solvent for the reactive dye during the heating process, keeps warm, takes out the cotton fabric, and soaps the fiber after the reactive dye is dyed in an organic solvent containing a cationic agent to complete the dyeing. The good solvent and the poor solvent of the reactive dye used in the method can be recycled repeatedly. Although the fixation rate of the method is high, two organic solvents need to be used simultaneously during its implementation, which leads to a relatively complicated recovery process, and the dyeing temperature is high and the required time is long, so the energy consumption is also relatively high. Summary of the invention

[0005] In order to solve the deficiencies of the prior art, the present invention provides an ethanol salt-free dyeing and washing method for reactive dyes. The present invention can achieve salt-free dyeing while maintaining color fastness and dyeing effect, and reduce the water consumption in the dyeing and washing process of textiles, reduce the impact on the environment, and promote the sustainable development of the textile industry.

[0006] The technical solution provided by the present invention is as follows:

[0007] An ethanol salt-free dyeing and washing method for reactive dyes comprises at least the following steps:

[0008] S1, pretreatment: placing the cotton fabric in an aqueous solution of an alkaline substance and a cationic modifier for padding;

[0009] S2, dyeing: placing the cotton fabric treated in step S1 in a dye solution of a reactive dye, heating it to a certain temperature, and keeping it warm for a period of time; wherein the solvent of the dye solution is a mixture of ethanol and water;

[0010] S3, color fixation: after dyeing for a period of time, add a color fixative to the dye solution and maintain the same temperature for a period of time;

[0011] S4, washing: washing the fixed cotton fabric in a solution containing a surfactant, and then drying to obtain a finished product; wherein the solution is a mixture of ethanol and water.

[0012] In the above technical scheme, the textile is firstly impregnated with alkali solution and cationic modifier solution, so that the cationic modifier is evenly distributed on the surface of the textile, and the fiber is positively charged by chemical reaction with the hydroxyl groups on the fiber to form covalent bonding, or the fiber is positively charged by physical adsorption, so as to improve the utilization rate of the dye. After dyeing, the floating color on the surface of the textile is cleaned with an ethanol solution added with an amphoteric surfactant or a nonionic surfactant. With the assistance of the amphoteric surfactant or the nonionic surfactant, the solubility of the reactive dye in ethanol can be increased, thereby reducing the amount of water used.

[0013] Specifically, in step S1, the alkaline substance is Na2CO3, NaHCO3 or NaOH, and the concentration is 1 to 30 g / L.

[0014] Specifically, in step S1, the cationic modifier is a quaternary ammonium salt compound with a concentration of 5 to 40 g / L.

[0015] The cationic modifier may be a commonly used quaternary ammonium salt compound, such as tetradecylamine polyoxyethylene ether diquaternary ammonium, octadecylamine polyoxyethylene ether diquaternary ammonium, and the like.

[0016] Specifically, in step S1, the bath ratio of the aqueous solution of the alkaline substance and the cationic modifier is 1:5 to 1:30, the treatment temperature is 30 to 90° C., and the treatment time is 10 to 60 min.

[0017] Specifically, in step S2, the volume ratio of ethanol to water in the solvent of the dye solution is 90%:10% to 98%:2%.

[0018] Specifically, in step S2, the dyeing temperature is 50-70°C, the heat preservation time is 30-40 minutes, and the bath ratio is 1:15-1:25.

[0019] Specifically, in step S2, commonly used dyes such as Reactive Yellow 145, Yellow CL-2Rp, etc. may be used.

[0020] Specifically, in step S3, a commonly used color fixing agent, such as EA40, etc., may be used.

[0021] Specifically, in step S3, the fixing temperature is 50-70° C., and the insulation time is 20-40 minutes.

[0022] Specifically, in step S4, the volume ratio of ethanol to water in the washing liquid is 50%:50% to 80%:20%.

[0023] Specifically, in step S4, the surfactant includes an amphoteric surfactant and / or a nonionic surfactant; the concentration of the surfactant is 5 to 100 g / L, and the soap bath ratio is 1:1 to 1:30.

[0024] Specifically, step S4 can be performed in a closed container or an open container.

[0025] Preferably, the surfactant is cocamidopropyl betaine or Tween 80.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1. The present invention modifies the pre-dyed cotton textile by using alkali solution and cationic modifier for coordinated treatment and then directly dyes the cotton textile, thereby improving the dyeing rate and fixation rate of the cotton textile.

[0028] 2. The present invention utilizes the fast dyeing speed and high dyeing rate of the dye in the ethanol-water system, and gives full play to the advantage of the high permeability of ethanol, so that the active dye can quickly penetrate into the cotton fiber for dyeing. At the same time, a proper amount of fixing agent is added during the dyeing process, which further improves the dyeing effect and fixing rate of the cotton fabric.

[0029] 3. The dyeing and washing process of the present invention is mainly carried out in ethanol, which can save a large amount of water required in the dyeing and washing process. The method avoids the use of inorganic salts in the entire dyeing process, thereby reducing the salt content in the wastewater and reducing environmental pollution. In addition, the present invention selects non-toxic ethanol as a solvent, which reduces environmental pollution, and ethanol has a lower boiling point and is easy to recycle and reuse.

[0030] 4. The washing method of the present invention reduces the amount of water used in both the dyeing and washing processes, has low energy consumption, can effectively remove floating colors on the surface of textiles, and at the same time maintains the color brightness and fastness of the textiles. The entire process is salt-free, avoiding the impact of large amounts of salt used in traditional processes on the environment. More importantly, ethanol, as an environmentally friendly organic solvent, has a simple production process, relatively low production cost, low boiling point, and is easy to recycle and reuse, which further reduces energy consumption and resource waste.

[0031] 5. The washing liquid of the present invention has a high ethanol content, which reduces the difficulty of ethanol recovery. DETAILED DESCRIPTION

[0032] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0033] Unless otherwise specified, the test methods used in the embodiments of the present invention are all conventional methods; the materials, reagents, etc. used are reagents and materials that can be obtained from commercial channels unless otherwise specified.

[0034] Example 1

[0035] The ethanol salt-free dyeing and washing method of reactive dyes provided in this embodiment comprises the following steps:

[0036] 1. Pretreatment: Soak 10g of six-layer cotton gauze in a mixed aqueous solution of 30g / L sodium carbonate and 20g / L tetradecylamine polyoxyethylene ether diquaternary ammonium, bath ratio 1:20, 90℃, 30min, one immersion and one rolling, the liquid rate is controlled at about 100%;

[0037] 2. Dyeing: Place the pretreated cotton fabric in a dye solution with an OWF of 0.2% Reactive Yellow 145, with a bath ratio of 1:20, and heat to 70°C for 30 minutes; wherein the solvent of the dye solution is 90% ethanol;

[0038] 3. Fixation: directly add 5mL of fixative EA40 into the working solution dyed for 30min, keep warm at 70℃ for 20min;

[0039] 4. Washing: Place the fixed cotton fabric in a sealed container containing 80% ethanol containing 30g / L cocamidopropyl betaine at 95℃ for 20min, with a bath ratio of 1:20, and dry to obtain the finished product. The color fastness test of the obtained active dye-dyed gauze is carried out, and the test results are shown in the table:

[0040]

[0041] Example 2

[0042] The ethanol salt-free dyeing and washing method of reactive dyes provided in this embodiment comprises the following steps:

[0043] 1. Pretreatment: Soak 10g of six-layer cotton gauze in a mixed aqueous solution of 2g / L NaOH and 20g / L octadecylamine polyoxyethylene ether diquaternary ammonium, bath ratio 1:20, 70℃, 45min, one immersion and one rolling, the liquid rate is controlled at about 100%;

[0044] 2. Dyeing: Place the pretreated cotton fabric in a dye solution with an OWF of 0.2% Reactive Yellow 145, with a bath ratio of 1:20, and heat to 70°C for 30 minutes; wherein the solvent of the dye solution is 90% ethanol;

[0045] 3. Fixation: directly add 5mL of fixative EA40 into the working solution dyed for 30min, keep warm at 70℃ for 20min;

[0046] 4. Washing: Place the fixed cotton fabric in a sealed container containing 30g / L Tween 80 in 80% ethanol at 95℃ for 20min, with a bath ratio of 1:20, and dry to obtain the finished product. The color fastness test of the obtained active dye-dyed gauze is carried out, and the test results are shown in the table:

[0047]

[0048] Example 3

[0049] The ethanol salt-free dyeing and washing method of reactive dyes provided in this embodiment comprises the following steps:

[0050] 1. Pretreatment: Soak 10g of six-layer cotton gauze in a mixed aqueous solution of 30g / L sodium carbonate and 20g / L tetradecylamine polyoxyethylene ether diquaternary ammonium, bath ratio 1:20, 90℃, 30min, one immersion and one rolling, the liquid rate is controlled at about 100%;

[0051] 2. Dyeing: Place the pretreated cotton fabric in a dye solution with an owf of 0.5% Yellow CL-2R p, with a bath ratio of 1:20, heat to 80°C, and keep warm for 30 minutes; wherein the solvent of the dye solution is 95% ethanol;

[0052] 3. Fixation: directly add 5mL of fixative EA40 into the working solution dyed for 30min, keep warm at 80℃ for 20min;

[0053] 4. Washing: Place the fixed cotton fabric in a sealed container containing 80% ethanol containing 30g / L cocamidopropyl betaine at 95℃ for 20min, with a bath ratio of 1:20, and dry to obtain the finished product. The color fastness test of the obtained active dye-dyed gauze is carried out, and the test results are shown in the table:

[0054]

[0055] Example 4

[0056] The ethanol salt-free dyeing and washing method of reactive dyes provided in this embodiment comprises the following steps:

[0057] 1. Pretreatment: Soak 10g of double-layer cotton gauze in a mixed aqueous solution of 2g / L NaOH and 20g / L tetradecylamine polyoxyethylene ether diquaternary ammonium, bath ratio 1:20, 90℃, 30min, one immersion and one rolling, the liquid rate is controlled at about 100%;

[0058] 2. Dyeing: Place the pretreated cotton fabric in a dye solution with an owf of 0.5% Yellow CL-2R p, with a bath ratio of 1:20, heat to 60°C, and keep warm for 50 minutes; wherein the solvent of the dye solution is 95% ethanol;

[0059] 3. Fixation: directly add 5mL of fixative EA40 into the working solution dyed for 30min, keep warm at 60℃ for 30min;

[0060] 4. Washing: Place the fixed cotton fabric in a sealed container containing 30g / L Tween 80 in 80% ethanol at 95℃ for 20min, with a bath ratio of 1:20, and dry to obtain the finished product. The color fastness test of the obtained active dye-dyed gauze is carried out, and the test results are shown in the table:

[0061]

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for dyeing and washing reactive dyes with ethanol without salt, characterized in that: At least the following steps are included: S1, pretreatment: placing the cotton fabric in an aqueous solution of an alkaline substance and a cationic modifier for padding; S2, dyeing: placing the cotton fabric treated in step S1 in a dye solution of a reactive dye, heating it to a certain temperature, and keeping it warm for a period of time; wherein the solvent of the dye solution is a mixture of ethanol and water; S3, color fixation: after dyeing for a period of time, add a color fixative to the dye solution and maintain the same temperature for a period of time; S4, washing: washing the fixed cotton fabric in a solution containing a surfactant, and then drying to obtain a finished product; wherein the solution is a mixture of ethanol and water.

2. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S1, the alkaline substance is Na2CO3, NaHCO3 or NaOH, and the concentration is 1 to 30 g / L.

3. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S1, the cationic modifier is a quaternary ammonium salt compound with a concentration of 5 to 40 g / L.

4. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S1, the bath ratio of the aqueous solution of the alkaline substance and the cationic modifier is 1:5 to 1:30, the treatment temperature is 30 to 90° C., and the treatment time is 10 to 60 min.

5. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S2, the volume ratio of ethanol to water in the solvent of the dye solution is 90%:10% to 98%:2%.

6. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S2, the dyeing temperature is 50-70°C and the insulation time is 30-40 minutes.

7. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S3, the fixing temperature is 50-70° C. and the heat preservation time is 20-40 minutes.

8. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S4, the volume ratio of ethanol to water in the washing liquid is 50%:50% to 80%:20%.

9. The ethanol salt-free dyeing and washing method of reactive dyes according to claim 1, characterized in that: In step S4, the surfactant includes an amphoteric surfactant and / or a nonionic surfactant; the concentration of the surfactant is 5 to 100 g / L, and the soap bath ratio is 1:1 to 1:

30.

10. The method for dyeing and washing reactive dyes with ethanol without salt according to claim 1, characterized in that: In step S4, washing is performed in a closed or open container.

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