KR20030080346A - A Component Of Electromagnetic Wave Absorber - Google Patents
A Component Of Electromagnetic Wave Absorber Download PDFInfo
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- KR20030080346A KR20030080346A KR1020020018927A KR20020018927A KR20030080346A KR 20030080346 A KR20030080346 A KR 20030080346A KR 1020020018927 A KR1020020018927 A KR 1020020018927A KR 20020018927 A KR20020018927 A KR 20020018927A KR 20030080346 A KR20030080346 A KR 20030080346A
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
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- H—ELECTRICITY
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- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/02—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of metals or alloys
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/04—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of carbon-silicon compounds, carbon or silicon
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/20—Conductive material dispersed in non-conductive organic material
- H01B1/22—Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/20—Conductive material dispersed in non-conductive organic material
- H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
- H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
Abstract
Description
본 발명은 저전자파비흡수율을 나타내는 전자파흡수체 조성물에 관한 것으로, 전자기파 흡수용 Hard(BaO6Fe2O3, BaOnSrO(1-n)6Fe2O3) 및 Soft 페라이트분말(Ferrite Powder) 조성물(Ni-Zn-Cu Ferrite, Mn-Zn Ferrite), 코발트염이 피착 또는 흡착, 고용되어 있는 γ상의 산화철(Co-γ-Fe2O3), 산화철을 환원시킨 F23O4, 도전성의 카본블랙(C-B : Carbon-Black) 등을 혼합 사용하는 방법, 그리고 상기 분말상태의 소재류를 플라스틱(Plastic) 및 합성고무류와 혼합 사출 및 압출 또는 인서트(Insert) 사출하여, 안테나에 최적의 위치를 선택해서 부착 또는 삽입하여 사용하는 방법, 그리고 무선전화기나 무선호출기, 컴퓨터 등의 전자기기로부터 발생하는 전자파를 효과적으로 흡수할 수 있는 전자파흡수체 조성물에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave absorber composition exhibiting a low electromagnetic wave absorption rate, and includes a hard (BaO 6 Fe 2 O 3, BaOnSrO (1-n) 6 Fe 2 O 3) and a soft ferrite powder composition (Ni-Zn-Cu Ferrite, Mn-) for electromagnetic wave absorption. Zn Ferrite), γ-phase iron oxide (Co-γ-Fe2O3) in which cobalt salts are deposited or adsorbed, solid solution, F23O4 reduced iron oxide, conductive carbon black (CB: Carbon-Black), and the like. Method of mixing and injecting the powdered materials with plastic and synthetic rubber and injecting or extruding or inserting them, selecting and attaching or inserting the optimal position on the antenna, and using a radio telephone, pager or computer. The present invention relates to an electromagnetic wave absorber composition capable of effectively absorbing electromagnetic waves generated from such electronic devices.
현재 수많은 각종 전자기기류가 일상생활에 보편적으로 사용되고 있으며, 휴대폰이나 무선전화기, 컴퓨터, TV 등의 통신기기나 가전제품류 등 여러경로에서 발생되는 전자파와 그로 인하여 2차로 차량, 의료기기, 생산설비류의 자동화기기 등 전자파에 의하여 일어나는 오작동까지 사회적으로 이슈화되고 있는 실정이다.Nowadays, various kinds of electronic devices are commonly used in daily life, and electromagnetic waves generated in various paths such as mobile phones, wireless telephones, computers, TVs, communication devices, and home appliances, and thus, secondarily, vehicles, medical devices, and production facilities. Even the malfunction caused by electromagnetic waves such as automation equipment is being socially issued.
따라서 우려했던 전자파유해론(전파공해)이 현실로 대두되면서 수많은 석학들이 전자파의 인체 및 실험장비, 통신 및 생산자동화설비 등의 각종 기계류에 끼치는 유해론 등에 많은 연구가 계속되고 있으며, 그로 인한 규제방법도 규정되어 위의 여러 설비로부터 발생되는 유해 전자파를 차단하거나 또는 외부 전자파로부터 보호하려는 연구가 진행중이다.Therefore, as the theory of electromagnetic wave (electromagnetic pollution), which has been concerned, has emerged as reality, many scholars continue to study the harmful effects on various kinds of machinery such as electromagnetic waves, human body and experimental equipment, communication and production automation facilities, and the regulation method is also regulated. Therefore, research is underway to block harmful electromagnetic waves generated from the above facilities or to protect them from external electromagnetic waves.
현재까지는 페라이트코어(Ferrite Core), 전도성 금속류, 전도성 섬유류 및 전도성 플라스틱, 플라스틱 발포류 등을 사용, 각종 전자기파를 흡수 차폐하는 소재로 사용하여 왔으나 충분치 못하여 많은 문제점이 제기되고 있다.Until now, ferrite cores, conductive metals, conductive fibers, conductive plastics, plastic foams, and the like have been used as materials for absorbing and shielding various electromagnetic waves, but many problems have been raised because they are not sufficient.
한편, 휴대폰에서 전자파 발생은 무선통신을 수행하기 위하여 안테나에 고주파신호를 주어 공중으로 전파(Propagation)시킬 때 또는 공중에서 전송되어지는 소정의 고주파신호를 안테나에서 받아 무선통신을 수행할 때 나타나게 되는데, 이때 휴대폰안테나 주변, 특히 Hot Spot라 하여 안테나 본체가 단말기 내부회로와 연결되는 급전점(Feed Point)에서 많은 전자파가 발생하게 된다.On the other hand, the generation of electromagnetic waves in a mobile phone appears when a radio frequency signal is given to the antenna for radio communication to propagate to the air, or when a radio signal is received from the antenna to perform radio communication. At this time, a lot of electromagnetic waves are generated in the vicinity of the cell phone antenna, especially the hot spot at the feed point where the antenna body is connected to the internal circuit of the terminal.
이러한 전자파의 발생은 특히 송신하게 되는 경우 더 많은 전자파를 유발시키는데, 이때 발생하는 전자파는 인체 뇌의 온도를 상승시켜 기억력의 감퇴, 흥분 유발, 뇌종양 등의 원인이 될 가능성 등 인체에 유해하다는 연구결과가 속속 발표되고 있으며, 이에 미국은 1997년부터 연방통신위원회(FCC)를 통하여 전자파의 세기를 규제하고 있으며 세계 여러 국가에서도 이에 부응하고 있는 실정이다.The generation of electromagnetic waves induces more electromagnetic waves, especially when they are transmitted, and the generated electromagnetic waves increase the temperature of the human brain, which is harmful to the human body such as memory loss, excitement, and brain tumors. Since 1997, the US has regulated the intensity of electromagnetic waves through the Federal Communications Commission (FCC) since 1997, and many countries in the world have responded to it.
우리나라의 경우 휴대폰에서 발생하는 전자파의 세기를 2002년 1월부터 미국가 마찬가지로 전자파비흡수율(SAR : Speccific Absorption Rate)을 인체조직 1g중 1.6㎽/g 이하로 강력 규제키로 한 바 있고, 이를 지키지 않을 경우 제품의 형식승인을 내주지 않아 휴대폰의 판매행위 자체가 어렵게 되었으며, 미국 및 일본 등 세계 여러 국가에서도 이와 유사한 제재를 가하고 있어 수출 등에 막대한 영향을 주게 될 전망이다.In Korea, as of January 2002, the United States has decided to set the SAR (Speccific Absorption Rate) to less than 1.6㎽ / g out of 1g of human tissues. The sale of mobile phones has become difficult due to the lack of product type approval, and similar sanctions are imposed in many countries around the world, such as the United States and Japan.
한편, 휴대폰에서 방사되는 전자파를 줄이기(SAR) 위하여 임피던스 매칭의 변화방법(매칭을 틀어서 조절)으로 안테나와 단말기 내부 PCB 회로간의 최적의 매칭상태를 캐패시터(C), 인덕터(L), 저항(R) 소자 등을 가감 조절함으로서 SAR 허용기준치를 맞추는 원리를 적용하기도 하였으나, 이는 이득 및 감도가 낮아지는 단점을 해결하지 못하였다.On the other hand, in order to reduce electromagnetic waves radiated from the mobile phone (SAR), the optimum matching state between the antenna and the internal PCB circuit of the terminal is determined by changing the impedance matching method (by adjusting the matching), and the capacitor (C), the inductor (L), and the resistor (R). Although the principle of adjusting the SAR tolerance is applied by adjusting the device, etc., this does not solve the disadvantage of lowering gain and sensitivity.
또한 급전점(Feed Point) 부위에 Mn-Zn 또는 Ni-Zn-Cu Ferrite 칩 등의 자성체를 삽입하여 자성체에 교류가 흘렀을 때 저성체 내부에서 마이크로적 자기공명현상으로 안테나에서 발생하는 주파수에서의 전자파세기를 감쇠시키는 원리를 적용하기도 하였다.In addition, by inserting a magnetic material such as Mn-Zn or Ni-Zn-Cu Ferrite chip into the feed point, when the AC flows in the magnetic material, the electromagnetic wave at the frequency generated from the antenna due to the micro magnetic resonance phenomenon inside the low body. The principle of attenuation was also applied.
아울러 이와 유사한 방법으로 안테나의 돌출부위에 전자파흡수물질이라는 것을 반지형태로 제조하여 끼워서 전자파를 억제시키기도 하였으며, 또는 휴데폰의 급전점 부위에 전자파흡수물질이라는 것을 도포하는 방법 등, 여러 가지 형태의 방법이 연구 발표되고 있고 전자파를 흡수 차폐할 수 있다는 상품들까지 판매되고 있으나, 휴대폰의 가장 중요한 특성인 이득 및 수신감도, Tx Power 등의 통화품질의증감에 관한 구체적인 데이터(Data)를 제시한 경우는 없었다.In a similar way, the electromagnetic wave absorbing material was formed on the protrusion of the antenna in the form of a ring to suppress the electromagnetic wave, or various methods such as applying the electromagnetic wave absorbing material to the feed point of the mobile phone. Although it is being researched and sold to products that can absorb and shield electromagnetic waves, there have been no specific data on the increase or decrease of call quality such as gain, reception sensitivity, and Tx Power, which are the most important characteristics of mobile phones. .
따라서 본 발명은 보다 편리하고 진보된 전자파흡수체 조성물을 제조하고 더 나아가 저전자파비흡수율(SAR) 값을 나타내는 전자파흡수체 조성물을 제공하고자 하며, 즉 개인이동통신단말기(휴대폰), 무선전화기, 컴퓨터 등 각종 전자기기에서 발생하는 전자기파를 흡수할 수 있는 전자파흡수체 조성물 및 그 사용방법으로, 특히 이동통신단말기인 휴대폰의 전자파비흡수율(SAR) 규제에 대한 그리고 그 규제를 해결할 수 있는 저전자파비흡수율을 나타내는 전자파흡수체 조성물의 제시가 본 발명의 목적이다.Therefore, the present invention is to manufacture a more convenient and advanced electromagnetic wave absorber composition and further to provide an electromagnetic wave absorber composition showing a low electromagnetic wave absorption rate (SAR) value, that is, various mobile communication terminals (mobile phones), wireless phones, computers, etc. Electromagnetic wave absorber composition capable of absorbing electromagnetic waves generated from electronic devices and methods of using the same, in particular, the electromagnetic wave absorption rate (SAR) of the mobile phone as a mobile communication terminal and low electromagnetic wave absorption rate that can solve the regulation The presentation of the absorbent composition is an object of the present invention.
상기의 목적을 달성하기 위해 본 발명에 따른 저잔자파비흡수율을 나타내는 전자파흡수체 조성물은, 소재의 배합비를 소재의 배합비를 Co-γ-Fe2O3의 제조 및 마그네타이트와 카본블랙의 첨가로 제조한 방법과 같이 코발트염이 1-10% 혼합(피착 및 흡착, 교용)된 산화철(Co-γ-Fe2O3) 혼합소재를 플라스틱류와 혼합하여 사출 및 압출한 것을 특징으로 한다.In order to achieve the above object, an electromagnetic wave absorber composition showing a low residual wave specific absorption rate according to the present invention is prepared by preparing a compounding ratio of a material by preparing Co-γ-Fe 2 O 3 and adding magnetite and carbon black. As in the method, cobalt salt 1-10% mixed (adhered, adsorbed, used) mixed iron oxide (Co-γ-Fe2O 3 ) mixed material with the plastics, characterized in that the injection and extrusion.
아울러 위의 소재에 0-35%의 Fe3O4를 더 혼합시켜 항자력을 높히며, 1-10%의 도전성 카본블랙을 더 혼합시키고, 특히 Co-γ-Fe3O4: Fe3O4: 도전성 C-B의 배합비가 55-99wt% : 0-35wt% : 1-10wt%로 조성되는 것을 특징으로 한다.In addition, 0-35% of Fe 3 O 4 is further mixed with the above material to increase the coercive force, and 1-10% of the conductive carbon black is further mixed, especially Co-γ-Fe 3 O 4 : Fe 3 O 4 : The compounding ratio of electroconductive CB is 55-99wt%: 0-35wt%: 1-10wt%, It is characterized by the above-mentioned.
또한 소재의 배합비를 소재의 배합비를 Co-γ-Fe2O3의 제조 및 마그네타이트와 카본블랙의 첨가로 제조한 방법과 같이 코발트염이 1-10% 혼합(피착 및 흡착, 교용)된 산화철(Co-γ-Fe2O3) 혼합소재를 플라스틱류와 혼합하여 사출 및 압출하며, 위의 소재에 0-35%의 Fe3O4를 더 혼합시켜 항자력을 높이며, 1-10%의 도전성 카본블랙을 더 혼합시키는 한편, Co-γ-Fe3O4 : Fe3O4 : 도전성 C-B의 배합비가 55-99wt% : 0-35wt% : 1-10wt%로 조성되며, 위의 혼합소재와 분자식이 BaO6Fe2O3나 BaOnSrO(1-n)6Fe2O3인 Hard 페라이트분말을 50-99wt% : 1-50wt로 혼합한 것을 특징으로 한다.In addition, iron oxide (Co-γ) mixed with 1-10% cobalt salt (coating, adsorption, and alternating) was prepared in the same manner as the method of preparing the material blending ratio by preparing the material blending ratio of Co-γ-Fe2O3 and adding magnetite and carbon black. -Fe2O3) mixed material is injected and extruded by mixing with plastics, 0-35% Fe3O4 is further mixed with the above material to increase the coercive force, and 1-10% more conductive carbon black, while Co- γ-Fe3O4: Fe3O4: Conductive CB compounding ratio of 55-99wt%: 0-35wt%: 1-10wt%, and the mixed materials and molecular formula BaO6Fe2O3 or BaOnSrO (1-n) 6Fe2O3 Hard ferrite powder 50-99wt%: characterized in that the mixture of 1-50wt.
그리고 소재류를 Nylon류, 폴리아세탈, 폴리우레탄 폴리프로필렌과 염소화 폴리에틸렌 또는 합성고무류와 1-99 : 90-1%로 혼합 사출 및 압출하고, 사출 및 압출한 조성물을 안테나의 메탈 상부와 스프링의 접촉부위에 삽입하여 전자파흡수체로 사용한 것을 특징으로 한다.The material is mixed and injected into nylon, polyacetal, polyurethane polypropylene and chlorinated polyethylene or synthetic rubber at 1-99: 90-1%, and the injected and extruded composition is contacted between the metal top of the antenna and the spring. Inserted into and characterized in that used as an electromagnetic wave absorber.
또한 Fe2O3 : NiO : ZnO : CuO를 50-75wt% : 10-20wt% : 8-15wt% : 7-15wt%를 Ni-Zn-Cu 연자성 페라이트의 제조방법을 통해 페라이트분말로 제조하며, Ni-Zn-Cu 페라이트분말 60-100wt%와 Fe3O4 0-40wt%의 조성으로 혼합한 것을 특징으로 한다.In addition, Fe 2 O 3: NiO: ZnO: CuO 50-75wt%: 10-20wt%: 8-15wt%: 7-15wt% by Ni-Zn-Cu soft magnetic ferrite manufacturing method through a ferrite powder, Ni- Zn-Cu ferrite powder is characterized in that the mixture of 60-100wt% and Fe3O4 0-40wt%.
아울러 위의 소재에 Fe3O4 0-30wt%와 도전성 C-B 0-10wt%의 조성으로 혼합하며, 조성물을 Nylon66,12 등의 폴리아세탈 또는 폴리프로필렌와 1-90wt% : 99-10wt%로 혼합 사출 및 압출한 것을 특징으로 한다.In addition, the composition is mixed with 0-30wt% Fe3O4 and 0-10wt% conductive CB, and the composition is injected and extruded with polyacetal or polypropylene such as Nylon66,12 at 1-90wt%: 99-10wt%. It is characterized by.
그리고 위의 조성물을 안테나의 외피나 내피로 사용하며, 혼합 사출 및 압출과정의 원활한 작업(배합비)를 위해 실란 카프링제 및 활제를 첨가하는 과정과, 사출 및 압출을 위하여 조성물을 폴리프로필렌, 폴리아세탈 등의 플라스틱류에 1-90wt%를 혼합 사출 및 압출한 것을 특징으로 한다.And the above composition is used as the outer skin or the inner skin of the antenna, the process of adding the silane capping agent and lubricant for the smooth operation (mixing ratio) of the mixing injection and extrusion process, and the composition of the polypropylene, polyacetal for injection and extrusion It is characterized in that the injection and extrusion of 1-90wt% to plastics, such as.
또한 외피, 내피를 동시에 안테나에 적용하고, 상기 소재를 스냅인 타입의 플라스틱몸체로 사출 및 압출하여 사용하며, 상기 플라스틱과 혼합하여 컨넥터로 사출하여 안테나에 부속으로 사용하는 것을 특징으로 한다.In addition, the outer skin, the inner skin is applied to the antenna at the same time, the material is injected and extruded into a snap-in type plastic body, and mixed with the plastic is injected into the connector, characterized in that used as an accessory to the antenna.
또한 위의 2가지의 소재류를 플라스틱과 혼합하여 사출 압출한 플라스틱 혼합 전자파흡수체 조성물을 가전제품류, 통신기기류, 전자기기류 및 자동화기기류에 사용하며, 위의 전자파흡수체 조성물을 도료화하여 사용하는 것을 특징으로 한다.In addition, the plastic mixture electromagnetic wave absorber composition, which is injected and extruded by mixing the two materials above with plastic, is used for home appliances, communication equipment, electronic equipment, and automation equipment, and the electromagnetic wave absorber composition is used by coating the above. do.
이하, 본 발명에 따른 저전자파비흡수율을 나타내는 전자파흡수체 조성물에 대한 바람직한 실시예를 상세하게 설명하면 다음과 같다.Hereinafter, a preferred embodiment of the electromagnetic wave absorber composition showing a low electromagnetic wave specific absorption rate according to the present invention will be described in detail.
[실시예 1] Mn-Zn Ferrite칩 제조Example 1 Manufacture of Mn-Zn Ferrite Chip
환형의 고리형태의 Mn-Zn 페라이트(조성비 Fe2O3 : MnO : ZnO = 67wt% : 18wt% : 15wt%) 칩과, Ni-Zn--Cu 페라이트(Fe2O3 : NiO : ZnO : CuO = 60wt% : 18wt% : 12wt% : 10wt%) 칩을 제조 안테나의 하부 메탈부위에 환형 고리형태의 소결칩을 삽입하여 SAR 및 상대이득(Gain) 수신감도 등을 측정하였다Cyclic cyclic Mn-Zn ferrite (composition ratio Fe2O3: MnO: ZnO = 67wt%: 18wt%: 15wt%) chip, Ni-Zn--Cu ferrite (Fe2O3: NiO: ZnO: CuO = 60wt%: 18wt% : 12wt%: 10wt%) The chip was manufactured by inserting an annular annular sintered chip into the lower metal part of the antenna and measuring SAR and gain reception sensitivity.
[실시예 2] Ni-Zn-Cu Ferrite칩 제조Example 2 Manufacture of Ni-Zn-Cu Ferrite Chip
67g의 Fe2O3(공업용), 18g의 MnO(공업용), 15g의 ZnO(공업용)을 소정의 물(상수도)과 같이 볼밀(Ball Mill)에 채워 넣고 4시간(Hr) 동안 습식 혼합분쇄 후,그 슬러리(Slurry)를 쟁반에 담아 110℃에서 완전 건조하였다.67 g of Fe 2 O 3 (industrial), 18 g of MnO (industrial), and 15 g of ZnO (industrial) are charged into a ball mill with predetermined water (water supply), wet mixed and ground for 4 hours (Hr), and then the slurry. (Slurry) was put in a tray and completely dried at 110 ℃.
건조된 소재를 60메쉬(259㎛) 망으로 채친 다음 붕판(Sagger)에 담아 전기로(Muffle Furnace)에 넣어 900℃에서 3Hr 동안 소성(Calcination)시켰으며, 전기로에서 노냉시킨 후 소정의 물(상수도)과 같이 볼밀에 넣어 4Hr 동안 분쇄 후 용기(쟁반)에 닫아 110℃에서 완전 건조하였으며, 건조된 소재를 60메쉬(Mesh)의 망으로 체친 다음에 결착제(PVA305) 및 윤활제(스테아린산 아연)를 첨가, 간이금형으로 1ton/㎠ 압력으로 성형 건조 후 1,180℃로 소결하였으며, 분위기는 질소를 사용하였다.The dried material was filled with a mesh of 60 mesh (259㎛) and then put in a sagger and placed in an electric furnace (Muffle Furnace), calcined for 3 Hr at 900 ° C. After cooling in an electric furnace, predetermined water (water supply) ) Into a ball mill and pulverized for 4Hr, then closed in a container (tray) and completely dried at 110 ° C. The dried material was sieved with a mesh of 60 mesh, and then a binder (PVA305) and a lubricant (zinc stearate) were added. The mold was dried at a pressure of 1 ton / cm < 2 > by addition, a simple mold, and then sintered at 1,180 DEG C. The atmosphere was nitrogen.
[실시예 3]Example 3
60g의 Fe2O3(공업용)와 18g의 NiO(공업용), 그라고 12g의 ZnO(공업용)를 소정의 물(상수도)과 함께 볼밀에 채워 넣고 4Hr 동안 습식 혼합분쇄 후 그 슬러리를 쟁반에 담아 110℃에서 건조하였으며, 건조된 혼합소재를 60메쉬(250㎛)의 망으로 체친 다음 붕판에 담아 전기로에 넣어 900℃에서 2Hr 동안 소성시켰다.60 g of Fe 2 O 3 (industrial) and 18 g of NiO (industrial) and 12 g of ZnO (industrial) are charged into a ball mill with a predetermined amount of water (water supply), wet mixed and ground for 4 Hr, and the slurry is put into a tray and dried at 110 ° C. The dried mixed material was sieved through a mesh of 60 mesh (250 μm), put in a platen, put in an electric furnace, and fired at 900 ° C. for 2 Hr.
전기로에서 노냉 후 꺼내고 CuO(공업용) 10g을 첨가하여 분쇄기(Attritor : 2m/m의 지르코니아볼)에 소정의 물과 함께 넣고 110℃로 안전 건조시켰으며, 소정의 결착제(PVA305) 및 윤활제(스테어린산 아연)를 첨가 후 간이금형을 이용 1ton/㎠ 압력으로 성형 건조 후, 다시 전기로에서 1,180℃(Peak Temp)로 소결하고 노냉시켜 시료를 제조하였으며, 제조한 Mn-Zn 페라이트칩 및 Ni-Zn-Cu 페라이트칩과 같이 안테나의 헬리칼 하부의 메탈부위에 각각 삽입 SAR, Gain을 측정하였다.After cooling down in an electric furnace, 10 g of CuO (industrial) was added and placed in a grinder (Attritor: 2 m / m zirconia ball) with predetermined water, and dried safely at 110 ° C. The predetermined binder (PVA305) and lubricant (ste After adding zinc nitrate), the mold was dried at 1ton / ㎠ pressure using a simple mold, and then sintered and heated at 1,180 ° C (Peak Temp) in an electric furnace to prepare a sample. The prepared Mn-Zn ferrite chip and Ni-Zn were prepared. -Inserted SAR and gain on the metal part of helical lower part of antenna like Cu ferrite chip were measured.
그 결과, 기본 안테나의 전자파비흡수율(SAR)은 1.91㎽/g이고, Mn-Zn 페라이트칩 삽입시 전자파흡수율은 1.52㎽/g로 0.39㎽/g이 저감되어 20-21%의 저감율을 보였으나 Gain(상대이득)이 -0.58㏈i로 나빠졌으며, Ni-Zn-Cu 페라이트칩 삽입시 SAR은 1.49㎽/g로 0.42㎽/g이 저감되어 22% 정도의 저감율을 보였으나 Gain이 -0.43㏈i 내지 0.45㏈i 나빠졌다.As a result, the specific absorption rate (SAR) of the basic antenna was 1.91 ㎽ / g, and when the Mn-Zn ferrite chip was inserted, the electromagnetic absorption rate was 1.52 로 / g and 0.39 ㎽ / g. Relative gain deteriorated to -0.58㏈i, and when Ni-Zn-Cu ferrite chip was inserted, SAR decreased to 1.49㎽ / g, 0.42㎽ / g, showing 22% reduction, but gain was -0.43㏈. i to 0.45㏈i worsened.
즉, Ni-Zn-Cu 페라이트칩을 삽입한 경우가 Mn-Zn 페라이트를 삽입한 경우보다 SAR 저감율이 많았으며 Gain에서도 약간 좋은 수치(Quility)를 나타내었고, 또한 수신감도 및 Tx Power 에서도 약간 좋은 수치를 나타내어 Ni-Zn-Cu 페라이트칩을 삽입한 경우가 좋은 특성을 보여주었다.In other words, when the Ni-Zn-Cu ferrite chip was inserted, the SAR reduction rate was higher than that of the Mn-Zn ferrite, and the gain was slightly better in gain, and also slightly better in the reception sensitivity and Tx power. The Ni-Zn-Cu ferrite chip was inserted to show good characteristics.
한편, 1960년대부터 안테나바(Antenna-Bar) 등 자심재료, 전파흡수체, 자왜재료, 마이크로파 소자-(가결정), 자기테이프, 압분자심, 방진제-(복합체), 마이크로 IC, 자기디스크-(박막)이 근래 자기헤드, 버블 디바이스, 마이크로파 소자, 과오자-(단결정) 등 전자부품의 많은 부분에 사용되고 있는 Cu-Zn, Mn-Zn, Ni-Zn, Ni-Zn-Cu 등 수많은 Soft Ferrite(연자성체)의 사용이 휴대폰의 SAR의 개선에는 어느 정도 기여할 수 있으나, 휴대폰의 가장 큰 중요 특성인 Gain, 수신감도, Tx Power 등에서 오히려 좋지 않은 결과가 나타났다.Meanwhile, since the 1960s, magnetic core materials such as antenna bars, radio absorbers, magnetostrictive materials, microwave elements-(temporary crystals), magnetic tapes, powder cores, dustproof materials-(composites), micro ICs, magnetic disks- Many thin ferrites (Cu-Zn, Mn-Zn, Ni-Zn, Ni-Zn-Cu) are used in many parts of electronic components such as magnetic heads, bubble devices, microwave devices, and over-crystal (single crystal). Although the use of (soft magnetic material) may contribute to the improvement of SAR of a mobile phone to some extent, the result is rather poor in gain, reception sensitivity, Tx power, etc. which are the most important characteristics of a mobile phone.
즉, Ni-Cu 페라이트칩 사용시 Fe2O3 : NiO : ZnO : CuO = 55-20wt% : 15-20wt% : 10-15wt% : 8-12wt%, 그리고 SAR, 수신감도에서만 약간의 긍정적인 면을 볼 수 있었다.In other words, when using Ni-Cu ferrite chip, Fe2O3: NiO: ZnO: CuO = 55-20wt%: 15-20wt%: 10-15wt%: 8-12wt%, and SAR, only slightly positive side can be seen there was.
따라서 본 발명에서는 전자파비흡수율(SAR)-감소율 20% 이상과 상대이득(Gain)-0.3㏈i 이하로, 바람직하기는 감소율 25% 이상과 Gain-0.3㏈i 이하, 수신감도 및 Tx Power는 기본 휴대폰과 같거나 향상되어야 하고, 낙하시험시 소손방지(소결칩의 파손방지, 페라이트칩을 삽입하기 위하여 메탈부위를 얇게 깎아 약간의 충격에도 메탈부위가 부러짐), 데이터의 재현성 확보 및 소재의 양산성(품질 및 대량생산), 가격경쟁력 제고 등을 목표로 연구 진행하여 왔으며, SAR의 규제치 1.6㎽/g(SAR을 측정하는 장비의 오차 10%를 감안시는 1.4㎽/g 미만이어야 함) 이내의 결과를 얻을 수 있도록 개발된 것이다.Therefore, in the present invention, the specific absorption rate (SAR)-reduction rate of 20% or more and the relative gain (Gain) -0.3㏈i or less, preferably 25% or more reduction and Gain-0.3㏈i or less, reception sensitivity and Tx Power is the basic It should be the same as the mobile phone or improved, and it will prevent damage during the drop test (prevent breakage of sintered chip, break the metal part by thinly cutting the metal part to insert ferrite chip), secure data reproducibility and mass production of material (Quality and mass production), price competitiveness, etc., and research has been carried out, and within the SAR of 1.6㎽ / g (it should be less than 1.4㎽ / g considering 10% error of SAR measuring equipment). It was developed to get results.
[실시예 4]Example 4
1.5% 정도의 XC-72R이나 케첸블랙 등의 카본블랙(Carbon-Black)이 혼합되어 있는 Co-γ-Fe2O3에 10%의 Fe2O4가 섞여있는 소재와 BaO6Fe2O3 분말소재의 비율을 3.5 : 3 중량비로 혼합 후, 그 혼합소재와 나일론(Nylon66) 레진 또는 염소화 폴리에칠렌(CPE)을 85 : 15의 비율로 혼합한 모양으로 사출 및 압출하여 메탈부위에 삽입 적용한다.Co-γ-Fe2O3 containing 1.5% of XC-72R or carbon black, such as Ketjen Black, is mixed with 10% Fe2O4 and BaO6Fe2O3 powder in a 3.5: 3 weight ratio. After that, the mixed material and the nylon (Nylon66) resin or chlorinated polyethylene (CPE) is injected and extruded into a shape in which the ratio of 85: 15 is mixed and applied to the metal part.
그리고 Fe3O4 분말(Power) 15%와 Ni-Zn-Cu 분말 85%의 혼합소재는 폴리우레탄(Poly Urethane)과 35 : 65의 비율로 안테나의 외피(Case)를 사출 적용한다.And Fe3O4 powder (Power) 15% and Ni-Zn-Cu powder 85% of the mixed material is a polyurethane (Poly Urethane) and 35: 65 ratio of the antenna (Case) is injected by injection.
또한 혼합소재(Fe3o4와 Ni-Zn-Cu)는 Nylon66 또는 폴리아세탈(Poly-Acetal)과 35 : 65의 비율로서 대롱 형태로 사출하여 안테나의 스프링(Helical)에 씌웠으며, 내피(Frame) 부위에 적용하여 위의 혼합물질을 기본 휴대폰에 삽입 및 쒸워서 SAR, Gain, 수신감도를 측정하였다.In addition, the mixed materials (Fe3o4 and Ni-Zn-Cu) were injected in the form of a long form at a ratio of 35:65 to nylon66 or polyacetal and covered with the antenna's spring. By applying and mixing the above mixture into the basic mobile phone, SAR, Gain, and reception sensitivity were measured.
즉, Fe3O4 13wt%와 Ni-Zn-Cu 페라이트 분말 85wt%의 혼합소재를 Nylon66,12 또는 Poly Acetal과 35wt% : 65wt%로 혼합, 내피(Frame)를 사출하여 스프링을 씌웠으며, Co-γ-Fe2O3의 제조 및 마그네타이트와 카본블랙의 첨가로 제조한 소재와 Nylon66,12 또는 염소화 폴리에틸렌을 85 : 15의 비율로 혼합 사출 및 압출하여 메탈(컨넥터) 상부에 삽입하고, Ni-Zn-Cu 연자성 페라이트의 제조를 통한 Fe3O4 15wt%와 Ni-Zn-Cu 페라이트분말 85wt%의 혼합소재를 PU(Poly urethane)와 35 : 65의 비율로 혼합 사출하여 외피(Case)로 씌운다.That is, 13 wt% Fe3O4 and 85 wt% of Ni-Zn-Cu ferrite powder were mixed with Nylon66,12 or Poly Acetal at 35wt%: 65wt%, and the spring was applied by injecting the inner skin and Co-γ- Nylon 66,12 or chlorinated polyethylene is mixed and injected into the upper part of the metal (connector), and the Ni-Zn-Cu soft magnetic ferrite is produced by mixing Fe2O3 and adding magnetite and carbon black at a ratio of 85:15. 15 wt% of Fe3O4 and 85 wt% of Ni-Zn-Cu ferrite powder were mixed and injected into PU (Poly urethane) at a ratio of 35:65 to cover the shell.
또한 Ni-Zn-Cu 연자성 페라이트의 제조를 통한 Fe3O4 15wt%와 Ni-Zn-Cu 페라이트분말 85wt%의 혼합소재를 Nylon66,12 또는 Poly Acetal과 35wt% : 65wt%로 혼합, 내피(Frame)를 사출하여 스프링을 씌우고, 동시에 Co-γ-Fe2O3의 제조 및 마그네타이트와 카본블랙의 첨가로 제조한 소재와 Nylon66,12 또는 염소화 폴리에틸렌(CPE)를 85wt% : 15wt%의 비율로 혼합사 및 압출하여 메탈(컨넥터) 상부에 삽입한다.In addition, 15% by weight of Fe3O4 and 85% by weight of Ni-Zn-Cu ferrite powder through the production of Ni-Zn-Cu soft magnetic ferrite were mixed with Nylon66, 12 or Poly Acetal in 35wt%: 65wt%. Injection-covered spring and at the same time mixed with a material manufactured by the production of Co-γ-Fe2O3 and the addition of magnetite and carbon black and nylon66,12 or chlorinated polyethylene (CPE) in a ratio of 85wt%: 15wt% Insert it into the top of the connector.
또한 Co-γ-Fe2O3의 제조 및 마그네타이트와 카본블랙의 첨가로 제조한 소재와 Nylon66,12 또는 CPE를 85wt% : 15wt%의 비율로 혼합 사출 및 압출하여 메탈 상부에 삽입하고, 동시에 Ni-Zn-Cu 연자성 페라이트의 제조방법과 같이 Fe3O4와 Ni-Zn-Cu 페라이트분말을 15wt% : 85wt%로 혼합한 소재를 PU와 35wt% : 65wt%의 비율로 혼합 사출하여 외피(Case)에 씌운다.In addition, the material prepared by the production of Co-γ-Fe2O3 and the addition of magnetite and carbon black, nylon66,12 or CPE was mixed and injected and extruded at a ratio of 85wt%: 15wt%, and inserted into the upper part of the metal, and simultaneously Ni-Zn- Like the method of manufacturing Cu soft magnetic ferrite, a mixture of Fe3O4 and Ni-Zn-Cu ferrite powder at 15wt%: 85wt% is mixed and injected with PU at a rate of 35wt%: 65wt% to cover the case.
그리고 기본 안테나와 본 발명을 통해 적용 제조한 안테나를 현재 출시된 휴대폰에 장착하여 측정한 결과, 전자파비흡수율인 감소율 25% 이상과 Gain-0.3㏈i 이하, SAR의 규제치 1.6㎽/g(SAR을 측정하는 장비의 오차 10%를 감안시는 1.4㎽/g 미만이어야 함) 이내의 결과를 얻을 수 있었다.In addition, as a result of measuring the basic antenna and the antenna manufactured by applying the present invention to a mobile phone currently released, 25% or more reduction rate and a Gain-0.3㏈i or less, SAR regulation value of 1.6 SAR / g In consideration of 10% error of measuring equipment, the result should be less than 1.4) / g).
한편, 상기의 실시예에서 제시한 수치는 본 발명의 보호범위가 한정되지 아니함은 물론이며, 당업자가 용이하게 변경할 수 있는 범위도 본 발명의 보호범위에 포함되고 오직 청구범위에 의해서만 보호범위가 한정됨은 당연하다.On the other hand, the numerical values set forth in the above embodiments are not limited to the scope of protection of the present invention, and the range that can be easily changed by those skilled in the art is included in the scope of protection of the present invention and the scope of protection is limited only by the claims. Of course.
이상에서 설명한 바와같이 본 발명의 저전자파비흡수율을 나타내는 전자파흡수체 조성물에 의하면, 보다 편리하고 진보된 전자파흡수체 제조방법을 제조하고 더 나아가 저전자파비흡수율(SAR) 값을 나타내는 전자파흡수체 제조방법을 제공하고자 하며, 즉 개인이동통신단말기(휴대폰), 무선전화기, 컴퓨터 등 각종 전자기기에서 발생하는 전자기파를 흡수할 수 있는 전자파흡수체 조성물 및 그 사용방법으로, 특히 이동통신단말기인 휴대폰의 전자파비흡수율(SAR) 규제에 대한 그리고 그 규제를 해결할 수 있을 것으로 기대된다.As described above, according to the electromagnetic wave absorber composition showing the low electromagnetic wave absorption rate of the present invention, there is provided a method for producing a more convenient and advanced electromagnetic wave absorber manufacturing method, and furthermore, a method for producing an electromagnetic wave absorber having a low electromagnetic wave absorption rate (SAR) value. That is, the electromagnetic wave absorber composition that can absorb the electromagnetic waves generated from various electronic devices such as personal mobile communication terminal (mobile phone), wireless telephone, computer, and the use thereof, in particular the electromagnetic wave absorption rate (SAR) of the mobile phone terminal It is expected to be able to address and to regulate regulations.
Claims (18)
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