Atmospheric pressure dyeing method of meta-aramid yarn

Aramid fiber is a high-strength, high-modulus, low-density and high-temperature-resistant flame-retardant fiber with good abrasion resistance. Due to its good chemical stability and excellent mechanical and physical properties, it can not only be used as a structural material and functional materials, and can also be used in combination with other materials.

Aramid is the collective name of meta-aramid and para-aramid. The limiting oxygen index (L01) of meta-aramid is 29. It will not drop in the flame and will self-extinguish when it leaves the flame. At a high temperature of about 400°C, the fibers are carbonized and become a thermal insulation layer, which plays a role in preventing external heat from entering the interior.

The invention relates to a method for normal pressure dyeing of meta-aramid yarn, which belongs to the technical field of textile printing and dyeing. Include the following steps:

A) Roughening of meta-aramid yarn:

the roughening process is: acid or alkali 10-20g/L, penetrant ≤ 2g/L, bath ratio 1: 10-20, temperature 90-100 ℃, time of 20-30min, washed with water after the roughening, to obtain the meta-aramid yarn with roughened fiber surface;

B) Activation of meta-aramid yarn

activate the roughened meta-aramid yarn on the fiber surface, the activation process is: cationic modifier 10-20g/L, bath ratio 1: 20-30, temperature is 60-90℃, the time is 30-40min, to obtain the meta-aramid yarn to be dyed;

C) Dyeing of meta-aramid yarn:

 dyeing the to-be-dyed meta-aramid yarn under normal pressure to obtain meta-aramid colored yarn, the cationic modifier described in step B) is polyepoxy Chloropropane Amines.

1. The normal pressure dyeing method of meta-aramid yarn, it is characterized in that the acid described in step A) is phosphoric acid, and described alkali is sodium hydroxide.

2. The normal pressure dyeing method of meta-aramid yarn is characterized in that the dyeing described in step C) is acid dye dyeing, reactive dye dyeing or direct dye dyeing.

3. The normal pressure dyeing method of meta-aramid yarn, it is characterized in that the dyeing process of described acid dye dyeing is: acid dye 2-10% (o.w.f), pH5-6, electrolyte 10-20g/L, bath The ratio is 1:15-20, the dyeing temperature is 90-100 DEG C, The dyeing time is 40-60min, and after the dyeing, washing, soaping, washing and drying are completed.

4. The normal pressure dyeing method of meta-aramid yarn is characterized in that the dyeing process of described reactive dye dyeing is: reactive dye 2-10% (o.w.f), bath ratio 1: 15-20, electrolyte 30-40g /L, the dyeing temperature is 60-90°C, the dyeing time is 30-40min, and the color is fixed after the dyeing is completed.

5. The normal pressure dyeing method of meta-aramid yarn, it is characterized in that described direct dyestuff, the dyeing process of dyeing is: direct dyestuff 2-10% (o.w.f), pH6-7, electrolyte 10-20g/L, The bath ratio is 1:15-20, the dyeing temperature is 90-100 DEG C, the dyeing time is 40-60min, and the dyeing is finished with washing, soaping, washing and drying.

In the dyeing of the meta-aramid yarn, the meta-aramid yarn to be dyed is dyed under normal pressure to obtain the meta-aramid colored yarn.

Advantages: Helps to save energy, avoids damage to fibers and is not harsh on dyeing equipment and makes operation simple; enables subsequent processing of fabrics with desired patterns according to the weaving process.