| 摘要 |
PROBLEM TO BE SOLVED: To improve a small-sized and light sealed effect by covering all or a part of a loaded surface of parts for a print distribution board loaded with electric parts with an electromagnetic sealed layer composed of an electromagnetic wave absorbing material formed by printing. SOLUTION: On the upper surface of a print distribution board 1, a semiconductive package 2 and other electric parts 3, which have a plurality of large unnecessary radiant noises or are likely to generate an electromagnetic wave, are mounted. The printed circuit board 1 is obtained by forming an electrode pattern 4 on the upper surface of the printed circuit board 1, jointing a lead terminal 5 of each semiconductor package 2 on the electrode pattern 4 with solder, and by jointing the electric parts 3 with solder 6. Paste of electromagnetic wave, which is kneaded with a highly pure thermosetting epoxy resin and ferrite composite powder composed of a high magnetic material and a high dielectric material, is applied by printing on the mounted surface of the parts of the printed circuit board 1, thereafter bubbles within paste are removed with vacuum debubbling to be cured so that an electromagnetic sealed layer 7, composed of an electromagnetic wave absorbing material of 500μm-1.0 mm in thickness, is formed.
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