To enable an electromagnetic wave absorbing sheet to exhibit a sufficient noise reducing effect even when the thickness of the sheet is reduced by constituting the sheet by alternately laminating pluralities of magnetic material layers on each of which soft magnetic alloy strips are arranged in parallel with each other or in a crossing state and insulating material layers upon another.
The principal section of an electromagnetic wave absorbing sheet 1 is composed of an insulating material 2, an adhesive 3, and soft magnetic alloy strips (magnetic strips) 4. The insulating material 2, adhesive 3, and strips 4 respectively work to support the strips 4, to stick the strips 4 to the material 2, and to magnetically absorb and electrically shield electromagnetic noise and the mechanical strength of the sheet 1 is secured by alternately laminating the material 2, adhesive 3, and strips 4 upon another. For example, a plurality of magnetic strips 4 is arranged in parallel with each other in a state such that the end faces of the strips 4 in the longitudinal direction are closely adhered to each other and the insulator 2 is laminated upon and under the strips 4 so as to sandwich the strips 4 from the top and bottom sides through the adhesive 3. Alternatively, a plurality of magnetic strips 4 is arranged longitudinally and latitudinally and the insulator 2 is laminated upon and under the strips 4 so as to sandwich the strips 4 from the top and bottom sides through the adhesive 3.
OSAKI TAKAAKI
ENDO HAJIME
YANAGAWA TSUTOMU
SENDA MASAKATSU
NIPPON TELEGRAPH & TELEPHONE
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