During the processing of transfer printing fabric, prob […]
During the processing of transfer printing fabric, problems such as insufficient fabric fastness and hardening will be encountered. How can these problems be solved?
(1) Graft modification, such as acetylation, benzoylation, etc. In this way, the fibers can receive disperse dyes.
(2) Surface polymerization. This method is to polymerize high molecular substances on the fabric surface, thus receiving disperse dyes like synthetic fibers, such as polyester method, styrene method, etc.
(3) Fiber expansion. Simulates the swelling phenomenon of polyester in the heated amorphous region, and accepts disperse dye gas to enter. However, due to the lack of "fixation" with fibers, the fastness is insufficient. Therefore, this method can only be used with other methods of "fixing" dyes. Polyethene glycol (molecular weight 200) is generally used for fiber expansion. It is not only a bulking agent for cotton fibers, but also a solvent for disperse dyes.
Combining the above methods, the common point is that natural fiber fabrics must be pretreated before transfer printing, thus increasing the production process and production cost. More importantly, in order to clean the residual non-functional substances on the fabric, water washing and drying are necessary, so that the wastewater discharge cannot be eliminated and the consumption of heat energy can not be increased, thus it is difficult to get rid of the heavy burden of traditional printing and dyeing production.