CS226348B1 - Method of fixing dyes on wool,polyacrylonitrile or polyester fibres - Google Patents

Description

The present invention relates to a method of fixing dye to ultra-short-dyed textile fibers, comprising forming a vacuum and heating with steam.

Conventional dyeing of fibers in a pull-out process requiring long baths places high demands on water and energy consumption. Modern dyeing, such as wool combs, from ultra-short baths is accomplished by applying dye to the fiber, followed by fixation in a continuous, semicontinuous or discontinuous manner. A continuous method, such as the method developed by the Australian research organization CSIRO, consists in applying a dye and textile aids with a high urea content to the comb, which then steams briefly. Another example of continuous dyeing of woolen combs is the Fleissner line, where the floated combs pass through a continuous steamer with a constant supply of saturated feathers, thereby fixing the dye to the fibers.

Invented and elaborated by the UK-based IWS International Wool Secretariat, the wool is also dyed with more urea, crushed and left to cool for 12 to 24 hours.

In the discontinuous method on which the invention is based, the dye application is also followed by steam fixation. In the steaming boiler, where the dyed towers are stored in the containers, a vacuum is created, then the temperature is increased by the steam supply to a fixation temperature of 105 ° C - for woolen combs, while the pump is connected. This achieves egal coloration in a relatively short time; the complete steaming cycle takes about 45 minutes for light shades and about 70 minutes for dark shades. However, steam is extracted and exhausted throughout the fixation, which is a disadvantage of this method. Polyester fibers are similarly colored, but the fixation temperature is 140-145 ° C; even the fixation time is longer.

The disadvantages of the known methods are eliminated by the method of fixing the dye on the textile fibers dyed from ultra-short baths, including vacuum generation and heating by steam, according to the invention, that the material is left in a steaming boiler after reaching the fixation temperature. to fix the dye. Wool and polyacrylonitrile threads are allowed to stand for 10 to 45 minutes, polyester threads for 20 to 60 minutes.

By shutting down the feather supply and suction: the dye fixation alone saves the feather and electric energy, which is the main advantage of the invention. For example, in wool shavings, as mentioned above, in light shades the steaming cycle lasts 45 minutes, of which 20 minutes fixation, when the method according to the invention does not consume energy. In dark shades the fixation time of the dye in the fiber is longer - from a steaming cycle of 70 minutes the fixation time is 45 minutes. The energy saving is 45:70 ... 64%. For polyester fibers, the entire cycle takes 45 to 90 minutes depending on the required color saturation, of which 20 to 60 minutes fixation. For polyacrylonitrile fibers, the fixation time is approximately the same as for wool.

In contrast to the other known methods mentioned above, urea, which in a higher amount in the waste, represents an environmental disadvantage, is not used; moreover, urea is an important raw material in other areas of the national economy, such as animal or plant production.

A further advantage is that the process according to the invention is carried out in a steamer of known, relatively simple construction; the aforementioned continuous steaming devices require a demanding method of sealing while continuously passing through the material. By the proposed steaming process, the dyes can be fixed in the fibers at temperatures above 100 ° C, using only the minimum amount of energy required to reach the fixing temperature.

The advantages of the fixing method according to the invention are illustrated by specific examples.

Example 1

Wool combs are covered with a dye bath with the following composition:

x% dye g / l wetting and penetrating agent 4 g / l densities g / l glacial acetic acid

The uptake of the bath after flocculation is 100% of the weight of the material. The picked combs are transferred to a steaming machine. A vacuum is formed in the steaming boiler in the first stage, after which the material is heated to a fixation temperature of 105 ° C by feeding saturated feathers. After shutting off the spring and vacuum pump at this temperature, the combs are allowed to rest for 10 to 45 minutes, depending on the desired color saturation. This is followed by a short start of the pump, about 5 minutes, to remove excess steam, thus completing the steaming cycle.

Example 2

Polyacrylonitrile fibers are impregnated with a dyeing bath of the following composition:

x% dye g / l of wetting and penetrating agent 4. g / l thickeners

2.5 g / l glacial acetic acid

2.5 g / l tartaric acid

Staining and fixation proceed as in Example 1.

Example 3

The polyester cable is overlaid with a dye bath of the composition: x% dye g / 1 wetting and penetrating agent g / 1 drip g / 1 sodium chlorate g / 1 tartaric acid

0.5 g / l dispersant

The uptake of the bath at the cloolation is 50% by weight of the material. After transferring the flocculated polyester cables to the steaming machine, a vacuum is generated by means of a vacuum pump and the material is heated to 145 ° C by superheated steam. Then the pump and steam supply are switched off and the material is fixed at 145 ° C for 20 to 60 minutes according to the color saturation.

After equalizing the internal and external pressure of the device, the fixation process is complete.

Claims (1)

A method of fixing dye to wool, polyacrylonitrile or polyester fibers dyed from ultra-short baths, including vacuum generation and feather heating, characterized in that the fibers are allowed to rest in a steaming boiler after reaching the fixation temperature when the steam supply and suction is reached. polyacrylonitrile fibers for 10 to 45 minutes, and for polyester fibers for 20 to 60 minutes.