| 摘要 |
PROBLEM TO BE SOLVED: To obtain a printed wiring board, in which the insulating property and the reliability of an insulating resin layer are superior by preventing under exposure and over exposure of an insulating resin. SOLUTION: This discoloring film 1 is used to form an insulating resin layer on a conductor circuit 2, by exposing and developing an insulating resin 3 on the conductor circuit 2. The discoloring film 1 is discolored, when the insulating resin 3 is developed and the exposure state of the insulating resin 3 is decided on the basis of the discoloration of the discoloring film 1, nonexposure and the careless double exposure of the insulating resin 3 are prevented, and the extent of degradation or the like of a discharge lamp is decided. |
