CN110373920B - Stripping method for polyester dyed knitted fabric - Google Patents

Abstract

A stripping method of a polyester dyed knitted fabric is characterized by adopting the following processes: (1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and filtering; (2) adding a stripping agent accounting for 70-80% of the conventional amount into the treatment solution, and fully stirring and dissolving; (3) and adding other auxiliary agents with conventional dosage into the treatment liquid to perform stripping treatment on the polyester knitted fabric dyed by the disperse dye. According to the invention, the biological polishing wastewater is used for stripping the disperse dye dyed polyester knitted fabric, the use amount of the stripping agent can be reduced by using the action of the cellulase remained in the wastewater, the purpose of efficiently stripping the polyester dyed knitted fabric can be achieved, and the processing cost is saved.

Description

Stripping method for polyester dyed knitted fabric

Technical Field

The invention relates to a stripping method for a polyester dyed knitted fabric, and belongs to the technical field of textile printing and dyeing.

Background

Dacron is the most widely used synthetic fiber variety, accounts for more than 60% of the world synthetic fiber output, and is widely used for clothing materials, bedding and other industrial fiber products. The polyester fiber has a series of excellent performances, is not easy to wrinkle, has good thermoplasticity, light resistance and elasticity, high breaking strength and elastic modulus, and also has good washing and wearing performance and stability. The terylene molecule only contains certain benzene ring, ester group, hydroxyl and the like, and has no other polar groups, so that the terylene has poor hydrophilicity and dyeability.

The disperse dye has good compatibility with terylene, high dye uptake on terylene and good dyeing fastness, and becomes a main dye for dyeing and printing terylene fibers. The disperse dyes have small molecules and simple structure, and are generally dispersed and suspended in the dye liquor in fine particles by virtue of a dispersant. During dyeing, the dye particles cannot dye the fibers, and only the dye molecules dissolved in water can dye the fibers. As the dye molecules in the dye solution continuously dye the fiber, the dye particles in the dye solution are continuously dissolved, and the dye in the dispersant micelle continuously releases dye single molecules.

The disperse dye has affinity to terylene, dye molecules in dye solution can be adsorbed by fiber, but the dye molecules are difficult to enter the fiber at normal temperature because of the tight arrangement of the terylene macromolecules. The terylene is thermoplastic fiber, when the fiber is heated to a temperature higher than the glass transition temperature, the macromolecular chain segment of the fiber moves violently, the intermolecular gap is increased, dye molecules can enter the fiber, and the dye-uptake rate is remarkably improved. The most commonly used method for dyeing the terylene knitted fabric by using the disperse dye is a high-temperature high-pressure dyeing method, the dyeing temperature is 120-140 ℃, and the dyeing is carried out in closed dyeing equipment. Along with the rise of the temperature of the dye liquor, the dye-uptake rate of the dye is greatly accelerated, and the dye adsorption capacity is also greatly improved.

At high temperature, the dispersion stability of the dye is reduced, and the dye particles are easy to coagulate into coarse particles or tar-like liquid drops to be adsorbed on the surface of the polyester fabric to generate color points. In addition, in the process of processing before the spinning forming or dyeing of the terylene, the supermolecular structure unevenness caused by uneven effects of heat, tension and the like of each part of the fiber can be exposed during dyeing, so that the terylene knitted fabric has dyeing defects such as color spots, color spots and the like. At this time, a certain amount of stripping auxiliary is often needed to strip the dyed fabric at a high temperature so that the dyed fabric can be repaired to a certain extent.

Biological polishing is a biological process, namely natural and regenerated cellulose fabrics such as cotton, hemp, rayon and the like are treated by cellulase, and the cellulase is effectively matched with mechanical stirring power to remove micro-fibers extending out of the surface, prevent the generation of fluffing and pilling phenomena, endow the fabrics with smooth appearance, soft hand feeling and other excellent wearability, and comprehensively improve the appearance and the internal quality of the fabrics. After the polishing treatment of the cellulase is finished, most of the cellulase remains in the treatment solution and is discharged along with polishing wastewater, thereby causing waste.

Disclosure of Invention

According to the invention, the biological polishing wastewater is used for stripping the disperse dye dyed polyester knitted fabric, the use amount of the stripping agent can be reduced by using the action of the cellulase remained in the wastewater, the purpose of efficiently stripping the polyester dyed knitted fabric can be achieved, and the processing cost is saved.

The invention comprises the following processes:

(1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and filtering;

(2) adding a stripping agent accounting for 70-80% of the conventional amount into the treatment solution, and fully stirring and dissolving;

(3) and adding other auxiliary agents with conventional dosage into the treatment liquid to perform stripping treatment on the polyester knitted fabric dyed by the disperse dye.

After the conventional biological polishing treatment is finished, the pH value of the treatment solution is adjusted to 8, the temperature is increased to 120 ℃ for treatment for 15min, and the spatial structure, the molecular structure, the physicochemical properties and the like of the cellulase are adjusted under the conditions of proper acid-base environment and high temperature. Filtering the treatment solution removes larger impurities that have come off the textile surface and unstable products during the treatment. Then, a commercially available stripping agent is added to the treatment solution, and the solution is sufficiently stirred and dissolved, so that the use amount of the stripping agent can be reduced compared with the conventional use amount. After the stripping agent is dissolved, other additives with conventional dosage are added into the treatment liquid, and the dyed polyester knitted fabric is stripped under the condition that cellulase coexists with the treatment liquid.

Detailed Description

The invention is further illustrated by the following examples and comparative examples.

Example 1

The method for stripping the light-color polyester knitted fabric dyed by the disperse dye comprises the following steps:

(1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and then filtering;

(2) adding a stripping agent accounting for 70% of the conventional amount into the treatment solution, and fully stirring and dissolving;

(3) and adding other auxiliary agents with conventional dosage into the treatment liquid to perform color stripping treatment on the light-color polyester knitted fabric.

Comparative example 1

The same light-colored polyester knit fabric as in example 1 was stripped by a conventional method, the process being as follows:

(1) adding a stripping agent with a conventional dosage into water, and fully stirring and dissolving;

(2) and adding other auxiliary agents with conventional dosage into the solution to perform color stripping treatment on the light-color polyester knitted fabric.

It can be seen that example 1 both recycles the biological polishing wastewater and saves the use of stripping agents. The test of the obtained stripping terylene knitted fabric shows that the stripping rate of the fabric obtained in the example 1 is 2 percent higher than that of the fabric obtained in the comparative example 1.

Example 2

The method for stripping the medium-color polyester knitted fabric dyed by the disperse dye comprises the following steps:

(1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and filtering;

(2) adding a stripping agent accounting for 80 percent of the conventional dosage into the treatment solution, and fully stirring and dissolving;

(3) and adding other auxiliary agents with conventional dosage into the treatment liquid to perform stripping treatment on the medium-color polyester knitted fabric dyed by the disperse dye.

Comparative example 2

The same medium color polyester knitted fabric as in example 2 was stripped by a conventional method, the process was as follows:

(1) adding a stripping agent with a conventional dosage into water, and fully stirring and dissolving;

(2) and adding other auxiliary agents with conventional dosage into the solution, and stripping the medium-color polyester knitted fabric dyed by the disperse dye.

It can be seen that example 2 both recycles the biological polishing wastewater and saves the use of stripping agents. The test of the obtained stripping terylene knitted fabric shows that the stripping rate of the fabric obtained in the example 2 is improved by 5 percent compared with that of the fabric obtained in the comparative example 2.

Example 3

The method for stripping the deep color polyester knitted fabric dyed by the disperse dye comprises the following steps:

(1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and filtering;

(2) adding a stripping agent accounting for 80 percent of the conventional dosage into the treatment solution, and fully stirring and dissolving;

(3) and adding other auxiliary agents with conventional dosage into the treatment liquid, and stripping the deep color polyester knitted fabric dyed by the disperse dye.

Comparative example 3

The same dark polyester knit goods as in example 3 was stripped using a conventional method, the process being as follows:

(1) adding a stripping agent with a conventional dosage into water, and fully stirring and dissolving;

(2) and adding other auxiliary agents with conventional dosage into the solution, and stripping the deep color polyester knitted fabric dyed by the disperse dye.

It can be seen that example 3 both recycles the biological polishing wastewater and saves the use of stripping agents. The test on the obtained stripping terylene knitted fabric shows that the stripping rate of the fabric obtained in the example 3 is 6 percent higher than that of the fabric obtained in the comparative example 3.

According to the embodiment and the comparative example, the method can be used for stripping the dyed knitted fabric of the polyester disperse dye by utilizing the biological polishing wastewater, so that the reuse of the wastewater is realized, the consumption of the stripping agent is reduced, and the processing cost is favorably reduced.

Claims (1)

1. A stripping method of a polyester dyed knitted fabric is characterized by adopting the following processes:

(1) after the conventional cellulase biological polishing treatment is finished, adjusting the pH value of the treatment solution to 8, heating to 120 ℃ for treatment for 15min, cooling the treatment solution and filtering;

(2) adding a stripping agent accounting for 70-80% of the conventional amount into the treatment solution, and fully stirring and dissolving;

(3) and adding other auxiliary agents with conventional dosage into the treatment liquid to perform stripping treatment on the polyester knitted fabric dyed by the disperse dye.