| 摘要 |
PROBLEM TO BE SOLVED: To prevent bleed-out by setting cure starting temperature, determined from a heating curve obtained when temperature is raised at a specific rate by means of a differential scanning calorimeter, within a specific range using paste for filling through holes for a printed wiring board. SOLUTION: A substrate 1 is placed in the center layer of a printed wiring board and a through hole S penetrating the substrate in the direction of thickness is formed in the substrate 1. A peripheral conductor layer 31 is formed on the outer surface of the substrate 1 with the through hole S formed around the open end of the through hole S, and a wall face conductor layer 32 is formed on the inner wall face of the through hole S. Thus, the through hole S is filled with a curing body 2 composed of paste for through hole filling, and the cure starting temperature determined from a heating curve obtained when temperature is raised at a rate of 10 deg.C/min by means of a differential scanning calorimeter is set to 90-130 deg.C. As a result, time required for curing is reduced and bleed-out is prevented.
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