What is the role of penetrants in dyeing and finishing?

The broad concept of penetrant refers to a class of chemicals that can help the substance to be penetrated into the substance to be penetrated. Generally, anionic or nonionic surfactants or organic and inorganic solvents are used in printing and dyeing.

In each printing and dyeing process, various auxiliaries need to be quickly and uniformly penetrated into the interior of the fabric to improve the reaction efficiency and benefit of various auxiliaries and the fabric. For this reason, penetrants are often used in the production process to achieve this. Purpose.

The penetration aid takes the water in the working solution as the carrier and enters the gap of the fabric fibers. Once the aid contacts the fiber, it will react, and the fiber that finally contacts the working solution will start the reaction the latest time, while the same position of the fiber will react. The physical and chemical reaction of the fabric is almost finished at the same time, which causes the difference in the reaction time between the inner and outer fibers of the fabric, and the phenomenon that the reaction does not occur.

The addition of the penetrant greatly shortens the time required for the reaction process, and the reduction of the time required for these steps greatly reduces the difference in the reaction time between the inside and outside of the fabric. extended, thereby improving the uniformity and consistency of the response across the entire batch of fabrics.

Permeability testing of penetrant: To detect the permeability of penetrant, only the permeability detected under process conditions is effective permeability, and the permeability detected under non-process conditions is not instructive. Different penetrants have different chemical properties, and the process conditions used are naturally different. In actual production, attention should be paid to the following properties of penetrants: ionic, reactive, temperature resistance, environmental protection, acid and alkali resistance, oxidation resistance and resistance. Reducibility, and finally permeability.

Requirements for penetrants in each process:

①Cold stack: anionic or non-ionic, alkali resistance, oxidant resistance, cloud point, permeability.

②Enzyme desizing: non-ionic, cloud point, permeability.

③ Scouring: anionic or non-ionic, alkali resistance, cloud point, permeability

④Oxygen bleaching: anionic or non-ionic, alkali resistance, oxidant resistance, cloud point, permeability.

⑤ Mercerizing: anionic or non-ionic, strong alkali resistance, permeability.

⑥ Grinding: anionic or non-ionic, permeability.

⑦Reactive dyeing solution: anionic or non-ionic, permeability.

⑧Vat dye dyeing solution: anionic or non-ionic, permeable.

⑨ Paint dyeing solution: anionic or non-ionic, permeable.

⑩ Active stripping solution: anionic or non-ionic, alkali resistance, reducing agent resistance, temperature resistance, permeability.

⑪Vat dye stripping solution: anionic or non-ionic, alkali resistance, reducing agent temperature resistance, permeability.