Abstract:
A silver coating method for glass powder is provided to enhance anti-corrosion and electro-magnetic wave shielding effect of the glass powder and to increase electric conductivity of the glass powder by introducing sensitized glass powder to a solution of silver compound, complexing agent and stabilizer then adding a reducing agent to the mixture. The method comprises the steps of: degreasing glass powder and etching the treated glass powder; sensitizing the treated glass powder; adding the sensitized glass powder to a solution including silver compound, complexing agent and stabilizer then introducing a reducing agent to the mixture within 5 minutes; and carrying out the coating process of the glass powder at 10 to 98deg.C for 5 to 60 minutes. Alternatively, the glass powder is replaced by plastic powder or ceramic powder. The complexing agent is ammonia water and the stabilizer is selected from ammonium bicarbonate and ammonium carbonate. The reducing agent is selected from hydrazine monohydrate, formaline, glucose, sugar alcohol and borohydride.
Abstract:
Provided are a method for preparing an aqueous urethane binder, and a paint composition for electromagnetic interference shielding containing the binder prepared by the method which is low in surface resistance, is excellent in adhesive strength and is environmentally friendly. The method comprises the steps of adding water to a prepolymer water dispersion; and controlling the content of a volatile organic compound to 5 g/L or less by vacuum distillation, to prepare an aqueous urethane binder. Preferably the prepolymer water dispersion is prepared by adding 20-25 parts by weight of polyoxypropylene glycol, 0.6-1.4 parts by weight of polyoxypropylene glycerin, 5-10 parts by weight of 2,4-toluene diisocyanate, 2.0-3.5 parts by weight of DMPA, 7.5-9.0 parts by weight of NMP, 1.0-3.0 triethylamine, 2.0-3.5 parts by weight of dibutyl tin dilaurate and water based on the weight of a urethane binder. The paint composition comprises 15-35 wt% of the aqueous urethane binder; 35-45 wt% of a silver powder; 0.01-0.09 wt% of a dispersant; 0.02-0.1 wt% of an antisettling agent; and 20-40 wt% of water.
Abstract:
본 발명은 테트라 에톡시 실란과 알루미늄 이소프로폭사이드를 이용한 알루미노 실리케이트의 제조방법에 관한 것이다. 본 발명의 방법으로 제조된 알루미노 실리케이트를 EMI(Electromagnetic interference) 코팅제용 바인더로 사용하면 기존 유기 바인더의 환경 오염성을 개선할 수 있고, 실리카 졸 및 알카리 실리케이트계 무기 바인더의 단점인 내수성 저하를 보완할 수 있다. 또한, EMC 전도 페인트(Electromagnetic compatibility conductive paint)를 제조하는데 있어 본 발명의 화합물을 바인더로 이용하면 친환경성 뿐만 아니라, 금속 필러(filler)의 함량을 줄일 수 있어 경제적인 이점이 있다. 알루미노 실리케이트, 테트라 에톡시 실란, 알루미늄 이소프로폭사이드
Abstract:
1. 청구범위에 기재된 발명이 속한 기술분야 본 발명은 상부 유전체층의 금속스트립을 이용한 고이득 선형편파 마이크로스트립 패치 배열 안테나에 관한 것임. 2. 발명이 해결하려고 하는 기술적 과제 본 발명은 마이크로스트립 패치 배열 안테나의 상부에 금속스트립을 갖는 유전체층을 위치시켜 제작이 용이하면서도 주파수 대역 특성이 좋은 고이득 마이크로스트립 패치 배열 안테나를 제공하고자 함. 3. 발명의 해결방법의 요지 본 발명은, 선형편파 마이크로스트립 패치 배열 안테나에 있어서, 하면에 접지도체를 위치시키고, 상면에 급전선과 이와 전기적으로 결합되어 에너지를 방사하는 제1 방사패치가 형성된 제1 하부 유전체층; 상기 제1 하부 유전체층의 상부에 위치하고, 주파수 대역폭 증가(광대역)를 위해 일면에 상기 제1 방사패치와 전자기적으로 결합되어 에너지를 방사하는 제2 방사패치가 형성된 제2 하부 유전체층; 및 상기 제2 하부 유전체층의 상부에 이격되어 위치하고, 일면에 '기판표면파의 전파방향을 조정하여 안테나 이득을 높이기 위한 금속스트립'을 갖는 상부 유전체층을 포함함. 4. 발명의 중요한 용도 본 발명은 패치 배열 안테나에 이용됨.
Abstract:
PURPOSE: A circular polarization microstrip patch antenna is provided to increase a radiation efficiency and to reduce a fabrication cost by connecting the first patch and the second patch with a form layer interposed therebetween. CONSTITUTION: The first patch antenna layer includes a dielectric layer(120) and a ground conduction layer(110) and radiates an energy by exciting a current through a power feed part(130) which is connected with the first patch(140) placed on one side of the dielectric layer. Tee second patch antenna layer includes a dielectric film(160) and radiates an energy by exciting a current through the first patch which is connected with the second patch(170) placed on one side of the dielectric film. The first form layer(150) is disposed between the first and second patch antenna layers to isolate the first and second patch antenna layers. The second form layer(180) is disposed on one side of the second patch antenna layer to protect the second antenna layer.
Abstract:
PURPOSE: A printing type multi-band antenna is provided to generate two resonant frequencies and reduce an existing resonant frequency by forming two additional lines to an end part of an inverse F antenna. CONSTITUTION: A printing type multi-band antenna includes a plurality of first radiation elements and a plurality of second radiation elements. The first radiation elements(300,301,302,303) are arranged on an upper surface of a dielectric substrate(309). The first radiation elements have a shape of inverse F, respectively. The second radiation elements(306,307) are arranged on one side of the first radiation elements of the upper surface of the dielectric substrate. The second radiation elements have a shape of inverse L, respectively. The first and the second radiation elements are partially located at a top part of a ground part(308). A first and a second sub-radiation element are formed at each end part of the second radiation elements.
Abstract:
PURPOSE: An angular spatial filter is provided to transmit and receive linear polarization and circular polarization by transmitting and restricting a transmitting signal and a receiving signal according to angles of the transmitting and the receiving signals. CONSTITUTION: An angular spatial filter includes a first dielectric film, a second dielectric film, a third dielectric film, a first form layer, and a second form layer. The first form layer(23a) is formed between the first dielectric film(22a) and the second dielectric film(22b) in order to form a gap between the first dielectric film and the second dielectric film. The second form layer(23b) is formed between the second dielectric film and the third dielectric film(22c). A first angular filter layer is formed with the first dielectric layer, the first form layer, and the second dielectric film. A second angular filter layer is formed with the second dielectric film, the second form layer, and the third dielectric film.
Abstract:
PURPOSE: A precise phase control method is provided to precisely control a beam steering angle by using a phase shifter having small number of phase control bits. CONSTITUTION: A precise phase control method comprises a first step of taking, as an input, a predetermined beam steering angle, and checking whether it is possible to perform a beam steering; a second step of calculating beam directions by dividing a beam if it is not possible to perform a beam steering; a third step of calculating intensities of beams with respect to the beam directions calculated in the second step; a fourth step of allocating phase shifters(240,250) of a phased array antenna with respect to the beam directions; and a fifth step of calculating phase differences between adjacent radiating elements(220,230) of the phased array antenna, and controlling phase shifters of beams by inputting phase values to the phase shifters allocated in the fourth step.