How to improve the cleaning effect after printing and dyeing textiles - can refer to

To this end, the author's experience based on long-term production practices. Summarize the following points:

1. Clear water to clean

The "clear" mentioned here refers to pure soft water. For example, many enterprises in Jiangsu and Zhejiang provinces use river water. Algae, sediment, and impurities in water should be filtered and removed. For water with high hardness, including tap water and groundwater in some places, 0.5-2 g/L of integrant should be added to the bath or added directly. The saponin GISAPAL (Germany Longta Company) (used specifically for printing and dyeing saponins) 0.5-1.5 g / L, in order to improve water quality, but also network adsorption of metal ions on the fiber. And no secondary stain. In actual dyeing of blue and black, the surface of the fabric often has a feeling of ash. In this regard, I have used the above additives at 50-60 °C under the conditions of fabric cleaning, and then iron dry, the comparison found that the bright clear and bright color.

2. The process specification is serious

First of all, the process must be reasonably regulated. For example, the dyeing and holding time should be at least 60-90 min when the disperse dyes are dyed dark polyester. When the active and direct dyes are dyed with viscose, due to the high initial dyeing rate on the surface of the fibers, it takes more than 60 minutes to reach the dyeing and penetration. Fabric density, yarn viscosity increase, dyeing time needs to be extended. Until it reaches transfection. Viscose fiber fabrics often appear dyed lighter. This is because the dyestuffs adsorbed on the surface of the fabric during the initial dyeing stage gradually diffuse into the interior as the dyeing time lengthens. If it does not reach the dyeing, it will not only cause difficulty in cleaning, but also decrease the fastness. And it will change color.

Therefore, for different dyes, different textiles. To take different dyeing process conditions. Otherwise it will not clean the net.

Secondly. Operation must be serious. Practice has proved that dyeing fabrics are treated with a fixing agent to form a transparent film only on the basis of sufficient washing, temporarily reducing the effect of dyes on water and fabrics. Improve color fastness. On the other hand, if the dyeings are not sufficiently washed, only a “color film” can be formed after the fixing agent is processed. Not only the color fastness can not be improved, but also the fabric feels greasy, and the equipment can be contaminated during the subsequent finishing. Therefore, the processed textile must be fully cleaned.

3. Improve the effectiveness of cleaning and dyeing equipment

To a certain extent, using dyeing equipment does not make it easy to wash the dyed material. Such as using sulphur dye dyeing cellulose fiber in the hair dyeing machine, despite repeated cleaning. Fiber floating color is still serious, and oxidation is not sufficient, affecting the color. And perform the tumbling cleaning. That is, after dyeing and washing twice, removing residual liquid, the fiber inside the machine will be poured out, pulled loose, and then continue to clean the machine, not only significant reduction in floating color, but also sufficient oxidation. Another example is reactive dyes dyeing by high temperature and high pressure jet overflow dyeing machine, sometimes it is washed many times, but there are still many floating colors. This is because the fabric capacity inside the machine is too much. The residual liquid on the fabric is not exhausted. Increased difficulty in cleaning. According to practice, The machine is used to dye deep black. After the previous two washings, the residual liquid should be drained as much as possible. Afterwards, it is cleaned with full-flowing water, and the higher the pressure of the clean water, the better the effect from the surface. Cleaning on a jigger, the water inside the machine is very clean. But touch the fabric with your hand. There is still a floating color.

Therefore, the application of overflow flow washing, with the injection of clean water. The water in the machine is full of fluctuations and the cleaning effect is improved, or a figure-eight spray pipe can be installed above the spindle of the two roll cloths in the machine, and the effect is more ideal.

4. Choose the right cleaning agent

A certain amount of surfactants, dispersants, acids, alkalis, salts, oxidizers, reducing agents, etc. must be added during the entire dyeing process of textiles. The addition of these chemical agents has become a potential factor affecting the ability of fabrics to be fully washed. If dyeing, it is generally necessary to add a leveling agent to control the dyeing speed of the dye, and to help the dye migrate from the higher concentration to the lower concentration. Until dyeing evenly; dispersant is only used for disperse dyes or less soluble dyes. Before the dye production process has been added, and sometimes the dyeing plant for a stable dispersion bath, to prevent staining defects, but also need to add. However, if the dispersant with poor quality is added, not only the dispersion effect will not be achieved, but sometimes secondary aggregation will occur, which will seriously affect cleaning. If you encounter this phenomenon. It is necessary to add a surfactant (such as dispersant WA) in the dye bath to promote dispersion and emulsification and avoid staining. For dyes with lower solubility, neutral co-solvents (such as urea) should be added, with little or no surfactant, because surfactants are not easy to clean.

As a cleansing agent after dyeing, an anionic/nonionic compound is preferred. If it is simply to remove dirt, anionic compounds such as soap can be used; if it is to remove the dyes (floating colors) remaining on the fiber or various assistive sentences added in the dye bath, since they interact with the dye. It will also be retained, and even a new compound will be produced, at which point an excellent cleaning agent will need to be selected. Such as hair / nitrile blended fabrics. Due to cationic dyes heavier on wool. It is bound to make cleaning difficult after dyeing.

Practice has proved that after dyeing of such fabrics and thick fabrics such as corduroy, it is best to use a white antifouling agent for the printing process and the effect is good. However, the overall cleaning effect of velvet fabrics is worse than that of thin textures. At present, the quality of clean lotions on the market is uneven, with varying prices.

In the author's opinion, a good cleaning agent should have the following:

(1) No color change;

(2) There is a certain increase in color fastness;

(3) Metal ion content should be within the detection range;

(4) No odor;

(5) Does not affect the feel and style.