Communications: directive radio wave systems and devices (e.g. – Radio wave absorber
Reexamination Certificate
2007-08-30
2011-12-06
Gregory, Bernarr (Department: 3662)
Communications: directive radio wave systems and devices (e.g.,
Radio wave absorber
C252S06251C, C252S062560, C252S062570, C252S062580
Reexamination Certificate
active
08072365
ABSTRACT:
Disclosed is a magnetic crystal for electromagnetic wave absorbing materials, having a structure of ε-MxFe2-xO3with 0<x<1, which has the same space group as that of an ε-Fe2O3crystal and which is derived from an ε-Fe2O3crystal by substituting a part of the Fe site therein with M. In this, M is a trivalent element having an effect of lowering the coercive force Hc of ε-Fe2O3crystal by the substitution. Concretely, the element M includes Al and Ga. An electromagnetic wave absorber having a packed structure of particles having such a substituent element M-added “M-substituted ε-Fe2O3crystal” as the magnetic phase may control the electromagnetic wave absorption peak frequency depending on the degree of substitution with the element M, and for example, the invention gives an electromagnetic wave absorber applicable to a 76 GHz band for on-vehicle radars.
REFERENCES:
patent: 4023174 (1977-05-01), Wright
patent: 4118704 (1978-10-01), Ishino et al.
patent: 5446459 (1995-08-01), Kim et al.
patent: 5668070 (1997-09-01), Hong et al.
patent: 5853889 (1998-12-01), Joshi et al.
patent: 5965056 (1999-10-01), Okuyama et al.
patent: 7101488 (2006-09-01), Kobayashi et al.
patent: 7108799 (2006-09-01), Kobayashi et al.
patent: 7708902 (2010-05-01), Ohkoshi et al.
patent: 7781082 (2010-08-01), Ohkoshi et al.
patent: 2007/0218319 (2007-09-01), Ohkoshi et al.
patent: 2008/0057352 (2008-03-01), Ohkoshi et al.
patent: 11-354972 (1999-12-01), None
patent: 2004-179385 (2004-06-01), None
patent: 2005-005286 (2005-01-01), None
patent: 2005-57093 (2005-03-01), None
patent: 2005-120470 (2005-05-01), None
patent: 2006-097123 (2006-04-01), None
patent: 2007-269548 (2007-10-01), None
patent: 2007-281410 (2007-10-01), None
S. Kuroki et al., “Control of Spin Reorientation Phenomenon in an epsilon-Fe2O3 Nanomagnet”; Digest of the 29th Annual Conference on Magnetics in Japan; 21pPS-16; p. 371; printed in the year 2005.
S. Sakurai et al., “Large Coercive Field and Spin Reorientation Phenomenon in epsilon-Fe2O3 Nanorod”; Digest of the 29th Annual Conference on Magnetics in Japan; 21pPS-17; p. 372; printed in the year 2005.
S. Sakurai et al., “Preparation of Magnetically Oriented epsilon-Fe203 Nanoparticles Exhibiting Large Coercive Field”; Digest of the 30th Annual Conference on Magnetics in Japan; 13pD-3; printed in the year 2006.
S.I. Ohkoshi, “Synthesis and Magnetic Properties of a Nanorod-type of Iron Oxide”; printed in the journal “Ceramics,” vol. 41, No. 4; p. 296-299; printed in the year 2006.
J. Jin et al., “Giant Coercive Field of Nanometer-Sized Iron Oxide”,Adv. Mater. (2004), 16, No. 1, Jan. 5, pp. 48-51.
J. Jin et al. “Formation of spherical and rod-shaped ε-Fe2O3nanocrystals with a large coercive field”,J. Mater. Chem(2005), pp. 1067-1071.
S. Sakurai et al. “Reorientation Phenomenon in a Magnetic Phase of ε-Fe2O3Nanocrystal”,Journal of the Physical Society of Japan, vol. 74, No. 7, Jul. 2005, pp. 1946-1949.
Hideo Kaneko and Motofumi Honma,Magnetic Materials, Maruzen, 1977, p. 123.
Edited by CSJ: The Chemical Society of Japan, CSJ: The Chemical Society of Japan Dai 86 Shunki Nenkai (2006) Koen Yokoshu I, Mar. 13, 2006, p. 511.
Kuroki Shiro
Namai Asuka
Ohkoshi Shin-ichi
Sakurai Shunsuke
Sasaki Shinya
Clark & Brody
DOWA Electronics Materials Co., Ltd.
Gregory Bernarr
The University of Tokyo
LandOfFree
Magnetic crystal for electromagnetic wave absorbing material... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic crystal for electromagnetic wave absorbing material..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic crystal for electromagnetic wave absorbing material... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4296573