1. Excelente resistencia al amarillamiento

During the preparation process, polyurethane resin for printing ink is mainly synthesized from aliphatic polyester and aliphatic isocyanate as the main raw materials. Compared with aromatic polyurethane, it has excellent optical stability and excellent yellowing resistance after film formation.

2. Excellent adhesion fastness to film substrates

The polyurethane resin ink chain segment contains polar groups such as carbamate, carbamate, ester bond, ether bond, and polar groups formed on the surface of many polar substrates such as PET, PA, etc. The hydrogen bond in turn forms a connector with a certain connection strength. After being made of polyurethane resin into ink, it is printed on the surface of polar plastic substrate with excellent adhesion fastness.

3. Has good affinity and wettability with pigments/dyes

Polyurethane resins used for ink are typically prepared from polyester or polyether polyols, alicyclic diisocyanates, and diamine/glycol chain extenders, and have a molecular weight of approximately tens of thousands. Due to the introduction of urea bonds in PU resin, polyurethane urea resin (PUU) is formed, which has good dispersion and wetting properties for pigments.

4. Good resin compatibility

Polyurethane resin for ink has good compatibility with aldehyde ketone resin, chloroacetic acid resin, etc. Users can add according to the actual situation and their own process formula to improve the overall performance of the ink.

5. Excellent film-forming effect

Ink polyurethane resin is structurally different from polyurethane resins used in other fields. Traditional polyurethane mainly reacts with polyester polyols/polyether polyols and isocyanate to form hydroxyl terminated polyurethane resins. The polar group in the molecular structure is carbamate. Mainly esters, with insufficient molecular cohesion to meet the film-forming performance requirements of ink resins. Therefore, the introduction of urea groups into polyurethane resin for ink on the basis of traditional polyurethane greatly improves the adhesive strength and film forming property of the resin itself.

6. Wide compatibility of organic solvents and good solvent release

The solubility of organic solvents in resins is achieved by the polarity of solvent molecules attracting solute molecules, which is commonly referred to as the same type of miscibility; Traditional polyurethane resins have extensive compatibility with organic solvents, ketones, esters, benzene, etc. Non alcohol organic solvents are excellent solvents. However, in the process of manufacturing ink, it is essential to add alcohol organic solvents in order to regulate the fluidity and viscosity of the ink. For traditional polyurethane resins, the addition of alcohol solvents greatly reduces the stability of the resin system, and often results in flocculation phenomena such as turbidity and incompatibility. However, due to the presence of urea groups, polyurethane resins used for ink have made their compatibility with alcohols a reality. However, it is worth pointing out that alcohol solvents are still counterfeit solvents. In the microscopic state, alcohol solvents encapsulate polyurethane resin molecules instead of real solvents. In real solvents, the polarity of molecules penetrates through the molecules, making the ink produced by polyurethane resin more flowable.