The Brief Introduction Of Waterborne Polyurethane Dye-Fixing Agent Working Principle And Its Develop
Waterborne polyurethane possess good film covering property in itself. If we introduce cationic chain extender at the time of compounding polyurethane, we can get cationic waterborne polyurethanne. The waterborne polyurethane dye-fixing principle is as follows: 1. Decreasing the solubility: there are large quantity of cation on the dye-fixing agent molecular. It will combine with the anion of the dye and produce insoluble color lake, which will help to improve the water washing fastness. 2. Increasing the adhesion between dye and fabric. The carbamic acid ester in the dye-fixing agent is easy to combine with the fabric and forming the hydrogen bond, which will improve the fastness greatly. 3. Covering the dye and water soluble group. Waterborne polyurethane is net cross-linked structure. It have good film-forming property. Because of the relative molecular mass, it will cover onto the surface of the fabric and form a sealing film which will cover ...