False drying refers to the phenomenon that the surface of the ink layer dries and the inner layer does not dry. It is easy to cause excess solvent residue and poor adhesion, causing the ink to stick back after rewinding.
Areas where multiple layers of solid color blocks are superimposed are more prone to anti-sticking. This is due to the following two reasons:
1. The ink layer is thick, the solvent residue is high, and the drying is incomplete.
2. After winding, the tension is concentrated on the long thin lines in the circumferential direction.
Reasons why ink may dry out easily in summer:
1. At high temperatures, the solvent on the surface of the ink layer evaporates quickly.
2. The high-humidity environment causes a large amount of moisture in the air to enter the ink, inhibiting the evaporation rate of the solvent in the ink.
3. In summer, large amounts of slow-drying solvents (such as ethyl ester) tend to remain.
Countermeasures:
1. Low viscosity printing
2. Control machine speed
3. Adjust the air volume to match the air temperature
4. Choose equipment with good drying capabilities. Medium and low speed machines with poor drying effects are more difficult to control.
5. When the humidity is too high, qualified printing companies can dehumidify the workshop.
