A method for clean dyeing of reactive dyes on home textile fabrics

Abstract

The present invention discloses a clean dyeing method of reactive dyes for home textile fabrics, which includes mercerizing and dyeing the home textile fabrics. During the mercerizing process, the home textile fabrics are modified. After mercerizing, it also includes desizing and water washing, and the pH value of the home textile fabrics after desizing and water washing is controlled at 8-9. The mercerized wet fabric after desizing and water washing is directly dyed with reactive dyes, and the dyeing is completed in a dyeing vat (jig dyeing machine); wherein, a cationic modifier is added to the dilute alkali solution sprayed by the cloth clips during the mercerizing process, and the cationic modifier is an epoxy group tertiary amine compound, preferably N,N-dimethyl-1-(2-epoxyethyl)methylamine. In the present invention, fiber modification is carried out synchronously with the spraying of dilute alkali by the cloth clips of the mercerizing machine, shortening the modification process in general processing. At the same time, the epoxy group tertiary amine compound is selected as the modifier, which can enhance the ionization of adjacent hydroxyl groups, making the modified fiber form a strongly nucleophilic secondary hydroxyl anion, which is beneficial to the reaction with reactive dyes.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving and emission-reduction dyeing and finishing processing for textile cleaning, and particularly relates to a method for clean dyeing of reactive dyes for home textile fabrics. Background Art

[0002] For traditional reactive dyeing of cotton fabrics, a large amount of salt must be added to improve the dye uptake rate, and then alkali is added to form a covalent bond between the dye and the fiber for fixation. However, the addition of salt and alkali will cause water quality deterioration and damage the ecological environment. In today's printing and dyeing industry, clean production is strongly advocated. Salt-free and alkali-free dyeing of reactive dyes promotes the realization of energy conservation and emission reduction, which is an important development trend, in line with the development goal of "energy conservation, emission reduction, ecological and environmental protection" in the printing and dyeing industry, and more in line with the requirements of ecological and environmental protection and clean production. Cationization of cotton fiber is a relatively effective way to achieve salt-free dyeing of cotton fabrics. By treating the cationic compound onto the cotton fabric, the negative charge on the surface of the cotton fabric is reduced, and the repulsive force between the cotton fabric and the reactive dye is decreased, enabling the reactive dye to achieve a higher dye uptake rate, better color fastness and levelness on the cotton fabric without adding salt for dye promotion. However, the addition of the cationic modification step reduces the production efficiency. For the neutral fixing reactive dye series Argazol NF, no alkali agent needs to be added during the dyeing process, and the covalent bond between the dye and the fiber can be achieved by increasing the dyeing temperature under neutral conditions. However, the cost of neutral fixing dyes is higher than that of ordinary dyes, which affects the use by enterprises. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for clean dyeing of reactive dyes for home textile fabrics, so as to solve one or more of the above-mentioned existing technical problems.

[0004] The present invention provides a method for clean dyeing of reactive dyes for home textile fabrics, including mercerizing and dyeing the home textile fabric. During the mercerizing process, the home textile fabric is modified. After mercerizing, it also includes desalting and water washing, and the pH value of the home textile fabric after desalting and water washing is controlled at 8-9. The mercerized wet fabric after desalting and water washing is directly subjected to reactive dyeing, and the dyeing is completed in a dyeing machine.

[0005] Among them, a modifier is added to the dilute alkali solution sprayed by the cloth clips during the mercerizing process. The cationic modifier is an epoxy group tertiary amine compound, preferably N, N-dimethyl-1-(2-epoxyethyl)methylamine.

[0006] In some embodiments, a cloth clip mercerizing machine is used in the mercerizing step. The mercerizing step is flat-width fabric feeding → first padding with alkali solution → tensioning roller → second padding with alkali solution → cloth clip chain widening → rinsing with dilute alkali → stack rolling → desalting box. The concentration of the rinsing dilute alkali is 50-60 g / L, and the concentration of the modifier is 20-30 g / L.

[0007] In some embodiments, the steps of vat dyeing are as follows: feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40°C for 2 passes → rotating and dyeing at 65°C for 2 passes → spraying for 2 passes → soaping at 95°C for 2 passes → washing with water at 90°C for one pass → discharging from the vat with cold water.

[0008] In some embodiments, the dilute alkali solution is a sodium hydroxide solution, the padding time is 12 - 18 h, and the padding temperature is 60 - 80°C.

[0009] In some embodiments, the reactive dye is a conventional reactive dye with a cyanuric triazine reactive group.

[0010] In some embodiments, the liquor pickup rate of the wet fabric is 60 - 70%.

[0011] Advantages of the present invention:

[0012] 1. The innovation of the present invention is that fiber modification is carried out simultaneously with the application of dilute alkali solution by the clips of the mercerizing machine, shortening the modification process in general processing. At the same time, the modifier is selected as an epoxy group tertiary amine compound, which can enhance the ionization of adjacent hydroxyl groups, enabling the modified fiber to form a strongly nucleophilic secondary hydroxyl anion, which is beneficial to the reaction with reactive dyes.

[0013] 2. The dyeing solution of the present invention does not contain electrolytes and alkali, and after dyeing, it can achieve the dyeing effect of conventional salt and alkali addition without neutralization, saving energy and reducing emissions, and realizing clean production; at the same time, since the pH value of the home textile fabric after desizing and washing with water is controlled at 8 - 9 (the traditional process requires desizing and washing with water until the pH value of the fabric is neutral), the number of mercerizing desizing and washing steps is reduced, and the mercerized wet fabric enters the dyeing vat immediately without drying, saving energy. Description of the drawings

[0014] Figure 1 It is the modification principle in the clean dyeing method of reactive dyes for home textile fabrics in an embodiment of the present invention. Detailed embodiments

[0015] The present invention will be further described below in conjunction with embodiments. The following embodiments are only used to more clearly illustrate the performance of the present invention and cannot be limited only to the following embodiments.

[0016] Example 1

[0017] A clean dyeing method of reactive dyes for home textile fabrics, including mercerizing and dyeing the home textile fabrics. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat fabric feeding → first padding with alkali liquor → fabric tensioning roller → second padding with alkali liquor → fabric clip chain stretching → rinsing with dilute alkali → padding and piling → desizing box. A modifier is added to the dilute alkali liquor sprayed on the fabric clips during the mercerizing process. The dilute alkali liquor is a sodium hydroxide solution, and the modifier is N,N-dimethyl-1-(2-methyloxiranyl)methanamine. The concentration of the dilute alkali is 55 g / L, the piling time is 16 h, the piling temperature is 70 °C, the concentration of the modifier is 25 g / L. The pH value of the home textile fabric after being washed in the desizing box is controlled at 8 - 9. The mercerized wet fabric after desizing and washing is directly dyed with reactive dyes. The liquor pickup rate of the wet fabric is 65%. The dyeing is completed in a dyeing machine. The dyeing steps in the dyeing machine are feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40 °C for 2 passes → rotating and dyeing at 65 °C for 2 passes → spray washing for 2 passes → soaping at 95 °C for 2 passes → washing at 90 °C for 1 pass → discharging with cold water.

[0018] Example 2

[0019] A clean dyeing method of reactive dyes for home textile fabrics, including mercerizing and dyeing the home textile fabrics. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat fabric feeding → first padding with alkali liquor → fabric tensioning roller → second padding with alkali liquor → fabric clip chain stretching → rinsing with dilute alkali → piling → desizing box. A modifier is added to the dilute alkali liquor sprayed on the fabric clips during the mercerizing process. The dilute alkali liquor is a sodium hydroxide solution, and the modifier is N,N-dimethyl-1-(2-methyloxiranyl)methanamine. The concentration of the dilute alkali for rinsing with dilute alkali is 50 g / L, the piling time is 12 h, the piling temperature is 60 °C, the concentration of the modifier is 20 g / L. The pH value of the home textile fabric after being washed in the desizing box is controlled at 8 - 9. The mercerized wet fabric after desizing and washing is directly dyed with reactive dyes. The liquor pickup rate of the wet fabric is 60%. The dyeing is completed in a dyeing machine. The dyeing steps in the dyeing machine are feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40 °C for 2 passes → rotating and dyeing at 65 °C for 2 passes → spray washing for 2 passes → soaping at 95 °C for 2 passes → washing at 90 °C for 1 pass → discharging with cold water.

[0020] Example 3

[0021] A clean dyeing method of reactive dyes for home textile fabrics, including mercerizing and dyeing the home textile fabrics. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat-width fabric feeding → first padding with caustic liquor → fabric tensioning roller → second padding with caustic liquor → fabric clip chain width expansion → rinsing with dilute caustic → padding and piling → caustic removal box. A modifier is added to the dilute caustic liquor sprayed on the clips during the mercerizing process. The dilute caustic liquor is a sodium hydroxide solution. The cationic modifier is N,N-dimethyl-1-(2-methyloxiranyl)methanamine. The concentration of the rinsing dilute caustic is 60 g / L, the piling time is 18 h, the piling temperature is 80 °C, the concentration of the modifier is 30 g / L, the pH value of the home textile fabric after water washing in the caustic removal box is controlled at 8 - 9. The mercerized wet fabric after caustic removal and water washing is directly dyed with reactive dyes. The liquor pickup rate of the wet fabric is 70%. The dyeing is completed in a dyeing vat. The dyeing steps in the dyeing vat are feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40 °C for 2 passes → rotating and dyeing at 65 °C for 2 passes → spraying and water washing for 2 passes → soaping at 95 °C for 2 passes → water washing at 90 °C for 1 pass → discharging from the vat with cold water.

[0022] Among them, the reactive dyes selected in Examples 1 - 3 are EC-2BL red produced by Huntsman Corporation.

[0023] Comparative Example 1:

[0024] A clean dyeing method of reactive dyes for home textile fabrics, including mercerizing and dyeing the home textile fabrics. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat-width fabric feeding → first padding with caustic liquor → fabric tensioning roller → second padding with caustic liquor → fabric clip chain width expansion → rinsing with dilute caustic → padding and alkali piling → caustic removal box. The dilute caustic liquor is a sodium hydroxide solution. The concentration of the dilute caustic is 50 g / L, the padding and alkali piling time is 18 h, the padding and alkali piling temperature is 60 °C. The pH value of the home textile fabric after water washing in the caustic removal box is controlled at 8 - 9. The mercerized wet fabric after caustic removal and water washing is directly dyed with reactive dyes. The liquor pickup rate of the wet fabric is 60%. The dyeing is completed in a dyeing vat. The dyeing steps in the dyeing vat are feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40 °C for 2 passes → rotating and dyeing at 65 °C for 2 passes → spraying and water washing for 2 passes → soaping at 95 °C for 2 passes → water washing at 90 °C for 1 pass → discharging from the vat with cold water.

[0025] The difference between Comparative Example 1 and Example 2 is that no cationic modifier is added to the dilute caustic liquor sprayed on the clips during the mercerizing process.

[0026] Comparative Example 2:

[0027] The dyeing methods of the prior art include mercerizing and dyeing the home textile fabrics. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat fabric feeding → first padding with caustic liquor → fabric tensioning roller → second padding with caustic liquor → fabric clip chain width expansion → rinsing with dilute caustic → caustic removal box. The dilute caustic liquor is a sodium hydroxide solution. The concentration of the rinsing dilute caustic is 50 g / L. The pH value of the home textile fabric after washing in the caustic removal box is controlled to be neutral. After drying the caustic removal and washing, reactive dyeing is carried out. The dyeing is completed in a dyeing vat. The dyeing steps in the dyeing vat are feeding at room temperature for one pass → rotating for one pass → rotating and dyeing for 2 passes at 40 °C (sodium sulfate 60 g / L) → rotating and dyeing for 2 passes at 40 °C (sodium carbonate 20 g / L) → rotating and dyeing for 2 passes at 65 °C → spraying and washing for one pass → neutralizing for 2 passes → soaping for 2 passes at 95 °C → washing at 90 °C for one pass → discharging from the vat with cold water.

[0028] Performance test:

[0029] 1. K / S value and L, a, b values

[0030] First, fold the dyed cotton fabric into 8 layers, adjust the light source of the Color-Eye 3100 color measurement and matching instrument to SAV, and add a small hole mask, and measure the K / S value and L, a, b values at the maximum absorption wavelength.

[0031] 2. Dyeing fastness

[0032] The color fastness to washing is determined according to GB / T 3921.1—1997 "Textiles - Tests for color fastness - Color fastness to washing: Test 1".

[0033] The color fastness to rubbing is determined according to GB / T 3920—1997 "Textiles - Tests for color fastness - Color fastness to rubbing".

[0034]

[0035] As can be seen from the above table:

[0036] Compared with Comparative Example 1 without adding a modifier additive, the fabric color depth K / S value, color fastness to rubbing and color fastness to washing of the dyeing method of the present invention have been greatly improved.

[0037] Compared with Comparative Example 2, the dyeing method with adding salt and alkali of the prior art, the fabric color depth K / S value, color fastness to rubbing and color fastness to washing of the dyeing method of the present invention are equivalent to those of the traditional dyeing fabric with adding salt and alkali. The present invention does not require adding salt or alkali, and can achieve the purpose of emission reduction and clean production.

[0038] In summary: In the embodiment of the present invention, fiber modification is carried out simultaneously with the application of dilute alkali to the cloth clips of the mercerizing machine, shortening the modification process in general processing. At the same time, the modifier is selected as an epoxy group tertiary amine compound, which can enhance the ionization of adjacent hydroxyl groups, enabling the modified fiber to form a strongly nucleophilic secondary hydroxyl anion, facilitating the reaction with reactive dyes. The specific modification principle is as Figure 1 shown. Moreover, no electrolyte and alkali are added to the dye liquor of the present invention, and after dyeing, neutralization is not required to achieve the dyeing effect of conventional salt and alkali addition, saving energy and reducing emissions, and enabling clean production. At the same time, since the pH value of the home textile fabric after desizing and water washing is controlled at 8-9 (the traditional process requires desizing and water washing until the pH value of the fabric is neutral), the number of mercerizing desizing and water washing times is reduced, and the mercerized wet fabric enters the dyeing vat immediately without drying, saving energy.

[0039] The above description is only the preferred mode of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several modifications and improvements can still be made, and these should also be regarded as within the protection scope of the present invention.

Claims

1. A method for clean dyeing of reactive dyes on home textile fabrics, characterized in that, It includes mercerizing and dyeing the home textile fabric. In the mercerizing step, a clip mercerizing machine is used. The mercerizing step is flat fabric feeding → first padding with caustic liquor → cloth tensioning roller → second padding with caustic liquor → cloth clip chain width expansion → rinsing with dilute caustic → cold pad batch → desizing box. A modifier is added to the dilute caustic liquor for cloth clips during the mercerizing process. The dilute caustic liquor is a sodium hydroxide solution, and the modifier is N,N-dimethyl-1-(2-methyloxiranyl)methanamine. The concentration of the rinsing dilute caustic is 50-60 g / L, the concentration of the modifier is 20-30 g / L, the pH value of the home textile fabric after desizing and water washing is controlled at 8-9, and the mercerized wet fabric after desizing and water washing is directly dyed with reactive dyes, and the dyeing is completed in a dyeing vat.

2. The clean dyeing method of reactive dyes for a home textile fabric according to claim 1, characterized in that, The dyeing steps in the dyeing vat are: feeding at room temperature for one pass → rotating for one pass → rotating and dyeing at 40 °C for 2 passes → rotating and dyeing at 65 °C for 2 passes → spraying for 2 passes → soaping at 95 °C for 2 passes → water washing at 90 °C for 1 pass → discharging from the vat with cold water.

3. The clean dyeing method of reactive dyes for a home textile fabric according to claim 1, characterized in that, The cold pad batch time is 12-18 h, and the cold pad batch temperature is 60-80 °C.

4. The clean dyeing method of reactive dyes for a home textile fabric according to claim 1, characterized in that, The reactive dye is a conventional reactive dye with a cyanuric triazine reactive group.

5. The method for clean dyeing of reactive dyes for a home textile fabric according to claim 1, characterized in that, The liquor pickup rate of the wet fabric is 60-70%.

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