| 摘要 |
PROBLEM TO BE SOLVED: To provide a land connection method for multilayer printed wiring board and a production system for multilayer printed wiring board in which reliability is enhanced through a simple structure at low cost. SOLUTION: A printed board 1 is held in a box 3 set in a molten solder bath 2 and the box 3 is evacuated by operating a rotary pump 4. Valves 5, 6 are opened while a valve 7 is closed during operation of the rotary pump 4. When vacuum in the box 3 reaches 10-2 mmHg, the valves 5, 6 are closed. Subsequently, a window (solder insertion port with valve) 8 is opened partially at a part where the box 3 touches solder liquid so that molten fuse intrudes into the box 3. Thereafter, valves 6, 7 are opened and the printed board 1 is taken out by opening the upper cover 9 of the box 3. |
