Alcohol ester soluble polyurethane ink: It is the second generation of environmentally friendly ink without benzene and ketone promoted after alcohol-soluble polyamide ink, mainly using isopropanol, ethyl acetate, and propyl acetate as solvents. Practical verification has shown that alcohol ester soluble polyurethane ink has many advantages such as easy operation, low price, stable performance indicators, bright gloss, good adhesion, and excellent heat resistance, and is the main ink variety in the current plastic flexible packaging printing industry.

Alcohol-soluble polyurethane ink: The core key technology is to introduce more urea groups and hydrogen bonds when synthesizing polyurethane resins to ensure compatibility with alcohol solvents. Because the polyurethane molecular chain contains more amino methyl esters, urea methyl esters, hydrogen bonds, ether bonds, and other polar groups on the surface of plastic products such as PET and PA, it forms joints with strong connecting strength and forms an ideal adhesion. In the formula system of alcohol-soluble polyurethane ink, the operating solvent is mainly ethanol and a small amount of ethyl acetate. Alcohol-soluble polyurethane ink can show excellent printing adaptability, excellent substrate adhesion, frost resistance, heat resistance, and can be compared with benzene-soluble chlorinated polypropylene ink.

Water-based polyurethane ink: Water-based polyurethane ink is a new major product in the polyurethane ink family. Compared with water-based acrylic resin ink and epoxy resin ink, water-based polyurethane ink has better wear resistance, water resistance, chemical resistance, impact resistance, and better flexibility and hardness. It is mainly used in rotogravure printing machines for food packaging printing on PET, PP, PE, PVC film, etc. processed by electrical sparking.

The reason why polyurethane ink series can be widely used in China's flexible packaging ink printing market depends primarily on the characteristics of polyurethane resin itself:

1. Compatibility of polyurethane resin: Polyurethane resin as the core can be matched with different auxiliary resins, such as polyketone resin, phenolic resin, chloroacetic acid resin, etc., to adjust the polyurethane ink system to show different characteristics to meet various operational needs.

2. Plasticity of polyurethane resins: In the synthesis process of polyurethane resins, different raw materials can be used to modify them, guiding the final product to have the desired functions.

The diversification of the functions of the polyurethane ink series is very compatible with the current situation and development of domestic flexible packaging printing. Therefore, polyurethane ink is highly favored in the soft packaging printing industry.