HOLE FORMING METHOD FOR PRINTED BOARD

摘要

PROBLEM TO BE SOLVED: To provide a hole forming method for a printed board where a work process is simple and performed in a short time. SOLUTION: Annular recesses 30 are so formed with laser beam, in advance, as not to penetrate a conductive layer 16. Both surfaces of a printed board 10 are coated with specified liquid photo resist 40, and the annular recesses 30 are filled with the liquid photo resist 40 as well. The printed board 10 is processed with exposure and image-manifest while an annulation 18 corresponding to the annular recesses 30 are formed on the other surface. The conductive layer 16 of the annulation 18 is removed by etching process. Then a photo- sensitized corrosion-resist film comprising the liquid photo resist 40 filled in the annular recesses 30 is released to form a hole at a specified position of the annular recesses 30.