WO2005023916A2 - Pate absorbant les micro-ondes mise en forme sur place - Google Patents

Pate absorbant les micro-ondes mise en forme sur place Download PDF

Info

Publication number
WO2005023916A2
WO2005023916A2 PCT/US2004/029726 US2004029726W WO2005023916A2 WO 2005023916 A2 WO2005023916 A2 WO 2005023916A2 US 2004029726 W US2004029726 W US 2004029726W WO 2005023916 A2 WO2005023916 A2 WO 2005023916A2
Authority
WO
WIPO (PCT)
Prior art keywords
resin system
microwave
liquid resin
filler
absorbing material
Prior art date
Application number
PCT/US2004/029726
Other languages
English (en)
Other versions
WO2005023916A3 (fr
Inventor
Richard N. Johnson
Christophe Loret
Original Assignee
Laird Technologies, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Laird Technologies, Inc. filed Critical Laird Technologies, Inc.
Priority to CN2004800258450A priority Critical patent/CN1849726B/zh
Publication of WO2005023916A2 publication Critical patent/WO2005023916A2/fr
Publication of WO2005023916A3 publication Critical patent/WO2005023916A3/fr

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems

Definitions

  • the present invention relates to the electronics industry, and more particularly, to the absorption of undesired radio-frequency (RF) emissions, such as microwave radiation, from electronic equipment, such as computers, telecommunications equipment, and the like.
  • RF radio-frequency
  • the present invention provides an alternative to the pads of the prior art, enabling a housing for electronic equipment to be provided with microwave-absorbing material in a more straightforward and convenient manner.
  • the present invention is a microwave- absorbing material which can be dispensed from standard form-in-place dispensing equipment. Such equipment may include a syringe-like applicator of the variety used to produce form-in-place gaskets and the like.
  • the microwave-absorbing material comprises a liquid resin system and a magnetic or lossy dielectric filler.
  • the liquid resin system is a silicon resin system and the magnetic filler is iron carbonyl powder.
  • the present invention is also a method for absorbing radio-frequency (RF) emissions in electronic equipment.
  • RF radio-frequency
  • the method comprises the steps of providing a liquid resin system; dispersing a magnetic or lossy dielectric filler in the liquid resin system; dispensing the liquid resin system having the filler into a housing for the electronic equipment; and curing the liquid resin system having the filler thereby forming a radio-frequency (RF) absorbing pad in si tu in the housing.
  • RF radio-frequency
  • the microwave-absorbing material that is, the liquid resin system having the filler is self-leveling and may be dispensed into a cavity in the housing. Alternatively, because of its thixotropic properties, the microwave- absorbing material may be dispensed onto a surface in the housing, where it will form a pad when cured.
  • FIG. 1 shows a dispensing system for the microwave- absorbing material
  • Figures 2A and 2B are perspective and side views, respectively, of a dispensing system depositing microwave- absorbing material onto a surface.
  • DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Accordingly, the present invention is a microwave- absorbing material which can be dispensed from standard form-in-place dispensing equipment. That is to say, it may be dispensed from a syringe-like applicator of the variety used to produce form-in-place gaskets and the like.
  • the microwave-absorbing material comprises at least two components, the first being a liquid resin system, which may be a silicone resin system. Alternatively, the liquid resin system may be a urethane, epoxy or other organic resin system.
  • the other component is a filler, such as a magnetic or lossy dielectric filler.
  • the magnetic filler is a filler material having a high magnetic permeability and a high electrical resistivity.
  • the magnetic filler material may be iron carbonyl powder.
  • the magnetic filler material may be iron powder; iron suicide; a ferrite (a compound of ferric oxide with another oxide) ; PERMALLOY ® (an alloy containing 78.5% nickel and 21.5% iron and having a high magnetic permeability and electrical resistivity) ; SENDUST (an alloy containing 85% iron, 9.5% silicon and 5.5% aluminum); carbon, that is, conductive carbon powder; fibers, such as graphite or metal fibers; and other fillers with electromagnetic (EM) properties, that is, high magnetic permeability and high electrical resistivity.
  • the microwave-absorbing material is loaded into a dispensing system, such as one incorporating a syringelike dispenser, in tubes.
  • a dispensing system 10 dispenses the microwave- absorbing material 12 into a cavity 14 in a housing for electronic equipment.
  • the microwave- absorbing material 12 self-levels to a desired thickness, thereby forming an RF (radio-frequency) absorbing pad in the cavity 14 when cured.
  • the thickness desired is predetermined to be that required to attenuate surface currents and EMI (electromagnetic interference) within the housing.
  • the microwave-absorbing material 12 of the present invention has a viscosity sufficient to maintain the filler material in a suspended state in the liquid resin system.
  • the amount of filler material used, and the thickness of the microwave-absorbing material 12, deposited in the cavity 14, are controlled to optimize the absorption of microwave energy at a given frequency or frequencies .
  • the microwave-absorbing material 12 of the present invention also has thixotropic properties. Thixotropy is the ability of certain colloidal gels to liquefy when agitated and to return to the gel form when at rest. In other words, gels of this type hold their shape when at rest and not under pressure, but flow freely on application of slight pressure. This property may be exploited to produce a pad of the microwave-absorbing material within a housing without the presence of a cavity.
  • FIGS 2A and 2B are perspective and side views, respectively, of a dispensing system 10 depositing microwave-absorbing material 12 onto a surface 16 in a housing for electronic equipment to form a pad 18 thereof. Because of its thixotropic properties, the microwave-absorbing material 12 maintains its shape as a pad 18 on the surface 16 and cures while keeping that shape . Modifications to the above would be obvious to those of ordinary skill in the art, but would not bring the invention so modified beyond the scope of the appended claims .

Abstract

L'invention porte sur un matériau absorbant les micro-ondes pouvant être déposé par des instruments usuels de mise en forme sur place, constitué d'un système de résines liquides et d'une charge, magnétique ou diélectrique à pertes. Dans l'exécution préférée, le système de résines liquides consiste en une résine de silicone, et la charge magnétique en une poudre de carbonyle de fer. Ledit matériau absorbant les micro-ondes se pose dans des boîtiers d'équipements électroniques et en particulier dans des cavités où il s'égalise et durcit de lui-même. En variante, on peut le poser sur les surfaces du boîtier où en raison de ses propriétés thixotropes il conserve sa forme et constitue une couche durcie de matériau absorbant les micro-ondes.
PCT/US2004/029726 2003-09-09 2004-09-09 Pate absorbant les micro-ondes mise en forme sur place WO2005023916A2 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2004800258450A CN1849726B (zh) 2003-09-09 2004-09-09 原位形成的微波吸收性涂料

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US50148803P 2003-09-09 2003-09-09
US60/501,488 2003-09-09

Publications (2)

Publication Number Publication Date
WO2005023916A2 true WO2005023916A2 (fr) 2005-03-17
WO2005023916A3 WO2005023916A3 (fr) 2005-06-02

Family

ID=34273048

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2004/029726 WO2005023916A2 (fr) 2003-09-09 2004-09-09 Pate absorbant les micro-ondes mise en forme sur place

Country Status (4)

Country Link
US (1) US20050139282A1 (fr)
CN (1) CN1849726B (fr)
TW (1) TWI357425B (fr)
WO (1) WO2005023916A2 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103183924A (zh) * 2011-12-29 2013-07-03 北京有色金属研究总院 镀Al空心玻璃微球和羰基铁粉的微波吸收复合材料及其制备方法
RU2791276C2 (ru) * 2021-02-15 2023-03-07 ООО "РТ-технологии" Эластомер - поглотитель электромагнитных волн

Families Citing this family (9)

* Cited by examiner, † Cited by third party
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CN100363130C (zh) * 2005-11-10 2008-01-23 北京科技大学 原位合成工艺制备核壳结构Fe-PAn的方法
CN101810886A (zh) * 2010-03-17 2010-08-25 清华大学 羰基铁粉的新用途
CN102304347B (zh) * 2011-06-08 2013-08-14 浙江大学 从农业废弃物微波复合制备SiC/羰基铁纳米复合材料及其方法
CN103658640B (zh) * 2013-12-27 2016-08-17 安徽华东光电技术研究所 一种用于速调管的铁硅铝吸收膏剂的配置、涂覆及烧结方法
CN105331331B (zh) * 2014-06-30 2017-03-15 比亚迪股份有限公司 一种微波吸收材料及其制备方法
DE102015105353A1 (de) 2015-04-09 2016-10-13 Hauni Maschinenbau Gmbh Saugbandförderer und Strangmaschine der Tabak verarbeitenden Industrie, Verwendung und Verfahren zum Messen von Materialeigenschaften eines Materialstrangs der Tabak verarbeitenden Industrie
CN104861753B (zh) * 2015-05-08 2017-05-31 湖北大学 一种具有电磁波吸收功能的环氧沥青涂层及其制备方法
CN105017948A (zh) * 2015-08-05 2015-11-04 普罗旺斯科技（深圳）有限公司 一种吸波片及其制造方法
CN111286225A (zh) * 2020-02-22 2020-06-16 东莞市鹏威能源科技有限公司 一种石墨烯吸波膜涂料及其制备方法和应用

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US4003840A (en) * 1974-06-05 1977-01-18 Tdk Electronics Company, Limited Microwave absorber
US4538151A (en) * 1982-03-31 1985-08-27 Nippon Electric Co., Ltd. Electro-magnetic wave absorbing material
US5552455A (en) * 1995-08-31 1996-09-03 Lockheed Corporation Radar absorbing material and process for making same
DE19949631A1 (de) * 1998-10-15 2000-05-18 Riken Tokio Tokyo Kk Verbundabsorber für elektromagnetische Wellen und Verfahren zum Anordnen des Verbundabsorbers
DE10115192A1 (de) * 2000-03-29 2001-10-25 Yazaki Corp Elektrisch leitende Paste
US20030044623A1 (en) * 2001-05-07 2003-03-06 Ikuo Sakurai Electromagnetic wave absorber

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WO1994010693A1 (fr) * 1992-10-30 1994-05-11 Lord Corporation Materiaux magnetorheologiques a action thixotrope
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Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4003840A (en) * 1974-06-05 1977-01-18 Tdk Electronics Company, Limited Microwave absorber
US4538151A (en) * 1982-03-31 1985-08-27 Nippon Electric Co., Ltd. Electro-magnetic wave absorbing material
US5552455A (en) * 1995-08-31 1996-09-03 Lockheed Corporation Radar absorbing material and process for making same
DE19949631A1 (de) * 1998-10-15 2000-05-18 Riken Tokio Tokyo Kk Verbundabsorber für elektromagnetische Wellen und Verfahren zum Anordnen des Verbundabsorbers
DE10115192A1 (de) * 2000-03-29 2001-10-25 Yazaki Corp Elektrisch leitende Paste
US20030044623A1 (en) * 2001-05-07 2003-03-06 Ikuo Sakurai Electromagnetic wave absorber

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103183924A (zh) * 2011-12-29 2013-07-03 北京有色金属研究总院 镀Al空心玻璃微球和羰基铁粉的微波吸收复合材料及其制备方法
RU2791276C2 (ru) * 2021-02-15 2023-03-07 ООО "РТ-технологии" Эластомер - поглотитель электромагнитных волн

Also Published As

Publication number Publication date
WO2005023916A3 (fr) 2005-06-02
TW200526716A (en) 2005-08-16
CN1849726B (zh) 2012-04-04
TWI357425B (en) 2012-02-01
US20050139282A1 (en) 2005-06-30
CN1849726A (zh) 2006-10-18

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