Water based polyurethane resin refers to a binary colloidal system in which a polyurethane resin is dissolved or dispersed in water.Water-based polyurethane resin has the advantages of easy to use, stable performance, strong adhesion, excellent gloss, good heat resistance, etc. It can be suitable for various printing methods, especially suitable for screen printing, plastic packaging and composite films.
The water-based polyurethane used in the ink industry requires good gloss, high bonding strength to materials, and good blocking resistance at a certain temperature.According to these performance requirements, there are the following requirements for the structural characteristics, functionality, synthetic formula, and process of polyurethane:(1) Select appropriate polyacids and polyols to synthesize polyester polyols with temperature resistance;(2) the introduction of polar groups with strong adhesion to the material;(3) Selecting suitable raw materials to improve the crystallinity of polyurethane;(4) Use coupling agents and other auxiliaries to improve the moisture and heat resistance of water-based polyurethane adhesives for inks.
At present, water-based polyurethane inks have been commercialized, can meet a variety of performance requirements, and are receiving increasing attention.The application of water-based polyurethane inks is mainly flexographic printing and gravure printing. Water-based polyurethane inks widely used abroad have good environmental protection, stable ink properties, high viscosity, strong tinting power, and high fastness. need.