Improvement And Development Of Printing And Dyeing Pretreatment Process

Conventional

Some basic elements such as oxidants, enzymes, heat and humidity can not be separated. Its development trend is high efficiency, high speed and short process. In the process, the amount of chemical agents should be reduced, or the direction of weakening should be improved, and the requirements for heat and humidity should be reduced.

Especially for cotton based printing and dyeing products, the pretreatment and processing must first remove the pulp and cotton mixture, and provide the basic requirements for the semi-finished products for the dyeing or printing process of the back road. Removing the chemical agents needed for the slurry and cotton mixture, the amount of heat and humidity and the discharge of residual liquid are important components of energy saving, emission reduction and consumption reduction in the whole printing and dyeing process, and are a "top priority", so we pay more attention to its improvement.

Improvement and improvement of traditional technology.

At present, the main chemicals commonly used in printing and dyeing pretreatment are alkali, enzyme, hydrogen peroxide and corresponding effective auxiliaries. According to the different raw materials, quality and size of processed products, the printing and dyeing products are a variety of raw materials, varieties, multi-purpose, multi-level products. Therefore, the process technology is changeable, and it is difficult to find "universal" technology, technology and equipment.

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However, the requirements for liquid volume, uniformity and concentration of chemicals are more important. Some products have been successfully used for the purpose of energy saving along with the successful development of high efficiency rolling cars. However, there is no critical breakthrough in the whole mercerizing process, or there are any innovative ways to replace the prospect. After the mercerization, a lot of light alkali is produced, which is often used in desizing and boiling and bleaching. The alkali also has a good supporting effect on the removal of chemical pulp and cottonseed hull and cotton mixture. How to control the dosage and process time of the selected chemicals basically meets the quality requirements of the products, and does not cause too much chemical residue to be washed and aggravate the burden of sewage treatment, which is worthy of attention. With the increasing demand for energy saving and emission reduction and the technological requirements of some varieties of raw materials, this technology has been concerned and applied.

Hydrogen peroxide

Development and application.

In the past process, the white liquor was used in the conventional process. Because of the heat treatment and the rapid decomposition of oxidants, technicians paid more attention to the development and application of hydrogen peroxide stabilizer. After dyeing, the amount of color, color fastness, brightness and so on were compared. The effect of energy saving and emission reduction and cost comparison should be paid attention to by one-time investment enterprises.

In recent years, due to the increasing environmental requirements for chemicals and waste water and waste disposal in chemical treatment, the development space for physical, mechanical treatment and finishing has been provided, in order to prevent excessive influence on fiber strength and control of whiteness uniformity. With the application of cold pad batch pretreatment process, because of the long time of stacking and the promotion of hydrogen peroxide decomposition, attention is paid to the development and application of activator of hydrogen peroxide. Heat also has "activation" effect on hydrogen peroxide. It is suggested that in the development and application, attention should be paid to the effective combination point of heat and activator in application.