Reasons and solutions:
1. The viscosity of the ink is wrong, it must be thinned.
2. The printing speed is fast, the screen distance is large, because the screen bounces away from the substrate too fast and the bubbles are pulled out.
3. The wrong solvent is used, and the miscibility with the ink is poor, so it is necessary to use a special solvent for the ink.
4. The use of quick-drying solvents under high temperature and low humidity conditions causes the surface conjunctiva to appear too fast and bubbles.
5. Bubbles are caused due to conditions such as the surface of the substrate is not easy to wet.
6. The ink expires and expires.