Title:
木質系電波吸収建材
Document Type and Number:
Japanese Patent JP4298706
Kind Code:
B2
Abstract:
[Object] Various electric wave absorbers for the GHz band have been developed. However, parameters for obtaining the optimal electric wave absorption characteristic are only the shape and the content of a dielectric material or a conductive material, and the degree of freedom of the parameters has been small. Furthermore, in a recent wireless LAN, electric wave absorbers that can be used for absorbing potentially dangerous electric waves in a plurality of bands, for example, in two frequency bands of 2.45 GHz band and 5.2 GHz band, have also been desired. [Solving Means ] In a woody electric wave absorber including a laminated magnetic woody material prepared by bonding facing plates composed of natural wood or a processed woody material with a magnetic layer composed of an adhesive containing a ferrite powder therebetween under pressure, the magnetic layer contains a nonmagnetic stainless steel powder in an amount in the range of 20 to 80 volume percent relative to the ferrite powder, the total volume content of the ferrite powder and the nonmagnetic stainless steel powder in the magnetic layer is in the range of 10% to 40%, the thickness of the magnetic layer is in the range of 0.5 to 5.0 mm, and the woody electric wave absorber has an electric wave absorption characteristic in which the center frequency of the electric waves absorbed lies in the range of 1 to 8 GHz and the amount of electric wave absorption is 10 dB or more in a 2.45 GHz frequency band or a 5.2 GHz frequency band.
Inventors:
Hideo Oka
Application Number:
JP2005516979A
Publication Date:
July 22, 2009
Filing Date:
December 20, 2004
Export Citation:
Assignee:
Japan Science and Technology Agency
International Classes:
H05K9/00; H01F1/00; H01F1/20; H01F1/36; H01F1/37; H01Q17/00
Domestic Patent References:
| JP2001118711A | ||||
| JP61269399A | ||||
| JP3020498U | ||||
| JP63155699U |
Other References:
成田幸一,岡英夫,磁性木材を用いたGHz帯用電波吸収体の作製に関する実験的検討,電気学会電磁環境研究会資料,日本,社団法人電気学会,2000年 1月18日,EMC-00-1~17,p.121-127
成田幸一,岡英夫,サンドイッチ型磁性木材の作製法と電波吸収体への応用,電子情報通信学会技術研究報告,日本,社団法人電子情報通信学会,1999年 4月22日,Vol.99,No.18,p.35-41
成田幸一,岡英夫,サンドイッチ型磁性木材の作製法と電波吸収体への応用,電子情報通信学会技術研究報告,日本,社団法人電子情報通信学会,1999年 4月22日,Vol.99,No.18,p.35-41
Attorney, Agent or Firm:
Yoshiyuki Nishi