MANUFACTURE OF WIRING BOARD PROVIDED WITH THROUGH HOLE

摘要

PURPOSE:To form an etching resist layer surely by a method wherein an insulating substrate is immersed in a specific photosensitive resist liquid, it is pulled up and a photosensitive resist layer is formed on the whole surface of the insulating substrate including the inside of a hole for through-hole use. CONSTITUTION:An insulating substrate 1 is immersed wholly in a photosensitive resist liquid 3 whose viscosity is 30 to 1500cPs and whose thixotropic value is 1.2 to 9; and it is pulled up. Thereby, the whole surface of the insulating substrate 1 including the inner wall surface of a hole 10 for through-hole use is covered with a photosensitive resist liquid layer; an etching resist layer of a prescribed pattern is formed of the photosensitive resist liquid layer. When the viscosity and the thixotropic value of the photosensitive resist liquid 3 are set properly, the photosensitive resist liquid 3 adheres satisfactorily to the hole 10 for throughhole use and the like. Thereby, the etching resist layer of a sufficient thickness can be formed surely on the inside and edge parts of the hole 10 for through-hole use.