| 摘要 |
A process for coating printed circuit boards has the following steps: the face of the printed circuit boards to be coated is maintained at room temperature and if required is heated up to about 120 DEG C; then , in a first step, a preferably photopolymerisable, fusible, low-molecular coating medium which is highly visquous to solid at room temperature and preferably has a mean molecular weight from 500 to 1500 and is about 10 mu m to 200 mu m thick, is applied on the surface(s) to be coated of the printed circuit board. In a second step, a second high-molecular photopolymerisable coating medium preferably having a mean molecular weight from 2,000 to 10,000 and 2 mu m to 20 mu m thick is applied on the first layer. The thus coated printed circuit boards are cooled down to room temperature and the double-layered photopolymerisable coating is exposed, developed and hardened, preferably in contact with a mask. A device for carrying out this process is also disclosed. |
