CN102747603A - Dyeing afterfinish process of cotton knitted fabric - Google Patents

Abstract

The invention discloses a dyeing and finishing process of cotton knitted fabrics, which belongs to the technical field of textile fabric dyeing and finishing processes, and comprises the following steps: drying the bad cloth after dyeing, adding a specified amount of clear water into the reactor first, and then adding Finishing agent, constantly stirring, and adjusting the pH value to 5-6, after the complete reaction, start sizing and rolling, and then carry out crosslinking, baking, cleaning, softening, dehydration, smoothing and softening agent, tenter heat setting, inspection and packaging; wherein the finishing agent is configured by citric acid and chitosan, and the percentages by weight of citric acid and chitosan are 40-60% and 40-60% respectively, and the proportion of finishing agent in clear water is The weight percent concentration is 20-50%. The cotton knitted fabric treated by the process of the invention has soft and smooth hand feeling, strong anti-shrinkage and anti-wrinkle ability, excellent air permeability, and the biggest feature is that it does not deform after being washed for 20 times.

Description

Dyeing Finishing Technology of Cotton Knitted Fabric

technical field

The invention discloses a dyeing and finishing process of cotton knitted fabrics, which belongs to the technical field of dyeing and finishing processes of textile fabrics.

Background technique

Because cellulose fiber has excellent water absorption, hygroscopicity, moderate strength and easy dyeing, it is the main material for underwear and shirts, especially natural fibers such as cotton and hemp. But fabrics made from these natural fibers inevitably crease and shrink when washed. At the same time, the regenerated cellulose fiber that appeared in the early 20th century, due to its low wet strength and the shrinkage and wrinkles during washing exceeded the allowable limit, made the creases and shrinkage during washing more serious. To solve this problem, anti-wrinkle finishing has appeared for cotton knitted fabrics.

Anti-wrinkle finishing, also known as easy care, durable press finishing, wrinkle resistance, washability, non-ironing, etc. That is to say, the fabric needs only a little ironing or no ironing after washing, and it has anti-wrinkle performance during wearing. The demand for anti-wrinkle cotton fabrics has doubled in recent decades. Cotton is a cellulose fiber rich in hydroxyl groups. 40% of the fibers are composed of closely arranged long-chain molecules in the crystalline region, and the rest are composed of loosely arranged long-chain molecules in the amorphous region. The molecules in the amorphous region are hydrogen bonded and loosely arranged, which contributes to the flexibility of the fiber. When the fiber is bent and twisted by an external force, the molecules in the amorphous region can move freely in the fiber, the hydrogen bonds of the macromolecules are deformed or broken, resulting in the displacement of the structural unit, and new hydrogen bonds are formed at new positions, resulting in Wrinkles occur. Depending on the duration and magnitude of the external force, the crease may eventually recover or form a permanent crease.

The anti-shrinkage and non-deformation means that the cotton fiber moderately shrinks and expands during the washing process. The so-called moderate shrinkage refers to the phenomenon that the stretched surface of the fabric is elongated in the warp direction during the processing process, and the fabric is slowly restored to its original size through washing. The so-called puffing and shrinkage refers to the expansion of fibers when they meet water. The phenomenon that the circumference of the yarn is enlarged, and the yarn that is slightly in contact with it at right angles increases the length required for distortion. Easing shrinkage can be slightly removed by relaxation treatment during fabric processing or continuous compression finishing in the final process, but it is not easy to prevent shrinkage caused by yarn bulking because it is the nature of cellulose fibers.

Therefore, the production process of cotton knitted fabrics with anti-shrinkage, anti-wrinkle and non-deformation as the main goals needs to be solved urgently.

Contents of the invention

The purpose of the present invention is to provide a dyeing and finishing process for cotton knitted fabrics with strong anti-shrinkage and anti-wrinkle effects.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A dyeing and finishing process for cotton knitted fabrics, comprising the following steps: drying the bad cloth after dyeing, adding a specified amount of clear water to the reactor, adding a finishing agent, stirring continuously, and adjusting the pH value to 5- 6. After the complete reaction, start sizing and rolling liquid, and then carry out crosslinking, baking, cleaning, softening, dehydration, smoothing and softening agent, tenter heat setting, inspection and packaging; the finishing agent is composed of citric acid and chitosan It is configured, and the weight percentages of citric acid and chitosan are respectively 40-60% and 40-60%, and the weight percentage concentration of the finishing agent in clear water is 20-50%.

As a further setting of the above scheme, the finishing agent is configured from citric acid and chitosan, and the weight percentages of citric acid and chitosan are 40% and 60% respectively, and the finishing agent accounts for 40% and 60% respectively in clear water. The weight percentage concentration is 30%.

In the baking process, the baking temperature is controlled at 120-160°C, the baking time is 2-3min, the liquid squeeze rate is 80-90%, the vehicle speed is 10-15m/min, and the baking process is in the heat-setting drawing process. Continuously in the frame machine.

The heat setting tenter machine is divided into six box areas, the temperature of the first box is controlled at 120°C, the second box is at 135°C, the third box is at 150°C, the first box to the third box are baking areas, and the fourth box To the sixth box is the setting area, the temperature is 160 ℃.

Chitosan, one of the chitin derivatives, has a similar molecular structure to cellulose. It is rich in sources, biodegradable, good water absorption, safe and non-toxic, and is a new type of green finishing material. Cotton fabric was finished with citric acid (CA) and chitosan, and the esterification reaction not only occurred between CA and cotton cellulose, but also between CA and the hydroxyl group of chitosan. The wrinkle recovery angle and DP grade of the treated cotton fabric were improved, the tensile and tear strength were improved, and it had a higher antimicrobial level. Antimicrobial performance remains above 80% despite repeated washing.

The cotton knitted fabric treated by the process of the present invention has a soft and smooth hand feeling, strong anti-shrinkage and anti-wrinkle capabilities, excellent air permeability, and the biggest feature is that it does not deform after twenty times of washing.

Detailed ways

Example 1

A dyeing and finishing process for cotton knitted fabrics, comprising the following steps: drying the bad cloth after dyeing, adding a specified amount of clear water to the reactor, adding a finishing agent, stirring continuously, and adjusting the pH value to 5, After the complete reaction, start sizing and rolling liquid, and then carry out crosslinking, baking, cleaning, softening, dehydration, applying smoothing and softening agent, tenter heat setting, inspection and packaging; the finishing agent is made of citric acid and chitosan , and the weight percentages of citric acid and chitosan are respectively 40%, 60%, and the weight percentage concentration of finishing agent in clear water is 30%.

In the baking process, the baking temperature is controlled at 120-160°C, the baking time is 2-3min, the liquid extrusion rate is 80-90%, the speed is 10m/min, and the baking process is in the heat setting tenter. Continuously. The heat setting stenter machine is divided into six box areas, the temperature of the first box is controlled at 120°C, the second box is at 135°C, the third box is at 150°C, the first box to the third box are baking areas, the fourth box to the The six boxes are the setting area, and the temperature is 160°C.

Example 2

A post-dyeing and finishing process for cotton knitted fabrics, comprising the following steps: drying the bad fabric after dyeing, adding a specified amount of clear water to the reactor, then adding a finishing agent, stirring continuously, and adjusting the pH value to 5.5, After the complete reaction, start sizing and rolling liquid, and then carry out crosslinking, baking, cleaning, softening, dehydration, applying smoothing and softening agent, tenter heat setting, inspection and packaging; the finishing agent is made of citric acid and chitosan , and the weight percentages of citric acid and chitosan are 60% and 40% respectively, and the weight percentage concentration of finishing agent in clear water is 50%.

For the baking process, the baking temperature is controlled at 120-160°C, the baking time is 2-3min, the liquid squeeze rate is 80-90%, the speed is 15m/min, and the baking process is in the heat setting tenter. Continuously. The heat setting stenter machine is divided into six box areas, the temperature of the first box is controlled at 120°C, the second box is at 135°C, the third box is at 150°C, the first box to the third box are baking areas, the fourth box to the The six boxes are the setting area, and the temperature is 160°C.

Example 3

A post-dyeing and finishing process for cotton knitted fabrics, comprising the following steps: drying the bad fabric after dyeing, adding a specified amount of clear water to the reactor, adding a finishing agent, stirring continuously, and adjusting the pH value to 6, After the complete reaction, start sizing and rolling liquid, and then carry out crosslinking, baking, cleaning, softening, dehydration, applying smoothing and softening agent, tenter heat setting, inspection and packaging; the finishing agent is made of citric acid and chitosan into, and the percentage by weight of citric acid and chitosan is 50% and 50% respectively, and the percentage by weight of finishing agent in clear water is 20%.

For the baking process, the baking temperature is controlled at 120-160°C, the baking time is 2-3min, the liquid squeeze rate is 80-90%, the speed is 13m/min, and the baking process is in the heat setting tenter Continuously. The heat setting stenter machine is divided into six box areas, the temperature of the first box is controlled at 120°C, the second box is at 135°C, the third box is at 150°C, the first box to the third box are baking areas, the fourth box to the The six boxes are the setting area, and the temperature is 160°C.

The above-mentioned embodiments are only used to explain the inventive concept of the present invention, but not to limit the protection of the rights of the present invention. Any insubstantial changes made to the present invention by using this concept should fall within the scope of protection of the present invention.

Claims (4)

1. the dyeing postfinishing process of a cotton knitted fabric; It is characterized in that comprising the steps: bad cloth oven dry with after the dyeing completion; Add the clear water of ormal weight in the reactor earlier, add finishing agent again, continuous stirring is also regulated pH value to 5-6; Treat promptly to begin the starching mangle after the complete reaction, carry out again crosslinked, bake, clean, soft, dehydration, go up smooth, soft agent, tentering HEAT SETTING, check and packing; Wherein finishing agent is formed by the configuration of citric acid and shitosan, and citric acid is respectively 40-60%, 40-60% with the percentage by weight that shitosan respectively accounts for, and while finishing agent shared concentration expressed in percentage by weight in clear water is 20-50%.

2. the dyeing postfinishing process of cotton knitted fabric as claimed in claim 1; It is characterized in that: said finishing agent is formed by citric acid and shitosan configuration; And the percentage by weight that citric acid and shitosan respectively account for is respectively 40%, 60%, and finishing agent shared concentration expressed in percentage by weight in clear water is 30% simultaneously.

3. the dyeing postfinishing process of cotton knitted fabric as claimed in claim 1; It is characterized in that: the described technology that bakes; Its baking temperature is controlled at 120-160 ℃, and the time of baking is 2-3min, and pick-up rate is 80-90%; The speed of a motor vehicle: 10-15m/min bakes technology and in the HEAT SETTING stenter, carries out continuously.

4. the dyeing postfinishing process of cotton knitted fabric as claimed in claim 3; It is characterized in that: said HEAT SETTING stenter is divided into six case districts, and the first oven temperature, degree is controlled at 120 ℃, second the case 135 ℃; The 3rd the case 150 ℃; First case to the three casees is for baking the district, and the 4th case to the is for six the casees shaping area, and temperature is 160 ℃.