| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive printed board which can uniformize the thermal expansion and thermal shrinkage when its main body is dipped in molten solder (flow soldered) with a simple structure, can prevent the warping of its main body which occurs in the conventional printed board when the main body is cooled, and is free from cost increase. SOLUTION: In this printed board having disposable portions 2 in its main body 1, belt-like patterns 3 are formed in the disposable portions 2 so as to prevent the warping of the main body 1.
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