There are clear requirements for the surface quality of printed words of medical aluminum foil, and there are physical and chemical indexes for the performance of protective layer and adhesive layer, so as to protect PTP aluminum foil with good barrier, health and safety, heat sealing and good physical and mechanical properties. In order to achieve the standard properties in the production process of PTP aluminum foil printing and coating, we still need to be familiar with the properties of the applied raw materials, and pay attention to some problems in the operation process

Printing inks cannot be mixed. For this reason, only one color of ink can be printed at a certain position on the paper at a time. The visual mixing of different colors printed close to each other gives the viewer the concept of continuously adjusting the image. To separate the colors from each other, you can use the screen to achieve this purpose. The generated dots are also called halftone or mesh tone.

In the process of high-speed printing, due to the effect of printing pressure, the sand mesh of the non graphic part of the printing plate is worn, resulting in the decrease of surface energy and water storage, resulting in the lipophilic and dirty non graphic part; Due to wear, the lipophilic hydrophobicity of the graphic part will change inversely, which will aggravate the ink emulsification and cause the pattern plate. Therefore, on the basis of ensuring good reproduction of pictures and texts, we should use as little printing pressure as possible. In addition, excessive printing pressure not only destroys the foundation of the graphic part of the printing plate and the sand mesh of the non graphic part, but also reduces the printing resistance of the printing plate.

The "sticky" ink with high viscosity and poor fluidity has good adhesion, large intramolecular friction or cohesion, strong adhesion and rapid fixation. Clear and round dots can be obtained by printing with "sticky" ink. Moreover, the "sticky" ink has good water resistance, is not easy to emulsify, has good "ink receiving", is easy to dry, has smooth dots and bright ink color Saturated color and thick ink layer.