The liquid flexible packaging ink is made by resin, pigment, additives and solvent. And the resin is the core of the ink, now PU resin becomes more and more popular, especially for the retorting application. We have the plasticizer, semi-film-forming and film-forming PU resin for ink. They are widely used for surface printing ink and lamination ink in both flexo and gravure printing technology. With the excellent color strength and adhesion property, they can meet different requirements and applications.

Plasticizer

The plasticizer grade PU resin is mainly for the surface printing ink, which cooperates with NC resin. Because it is polymeric plasticizer, there is no migration issue, and it has good heat, oil, fat, grease, and moisture resistance. Compared with NC resin, it is soft resin, and the hardness can be adjusted to get different performance. Because the molecular weight is low, the resin itself will be always sticky. All the products have excellent alcohol tolerance property, so they can make the flexo and gravure ink.

Semi Film Forming

The semi-film-forming grade PU resin is widely used for surface printing ink and simple lamination ink, which cooperates with NC resin. It is based on the plasticizer grade PU resin, but we increase the NCO content to make it harder. Then we get better adhesion property, anti-blocking property, heat resistance and grease resistance. We can also adjust the hardness to improve the performance. Because the molecular weight is high, the resin can be a film after evaporation. Due to the alcohol tolerance is normal, normally it is for gravure ink. And it also can be used as adhesion promoter.

Film Forming

The film-forming grade PU resin is mainly used for lamination ink, some also can make the surface printing ink due to excellent color strength. Normally it can cooperate with NC resin, vinyl resin (Vinyl Chloride-Vinyl Acetate Copolymer) and PVB resin, some also can make the 100% PU ink. All the products have good compatibility with different adhesives to achieve high bonding strength. Due to the ultra high molecular weight, it has excellent adhesion property, anti-blocking property, heat and chemical resistance, so it can do the hot filling, boiling and retorting application. They have excellent solvent release ability, so it is suitable for high speed printing ink. Some products have excellent alcohol tolerance, so it is possible make the flexo and gravure ink.