| 摘要 |
PROBLEM TO BE SOLVED: To provide a circuit board which can suppress chipping and cracking of its circumference and bend large without causing cracking nor chipping even when a large bending load acts. SOLUTION: The circuit board 10 is formed by coating at least part of the top surface and/or reverse surface of a substrate 1 made of a glass ceramic material with an overcoat glass layer 7, and the overcoat glass layer 7 is formed by adding an Al2 O3 filler or MgO filler to boric-acid based glass. |
