| With the development of information industry, and the extensive application of many kinds of electronic installationes which are used for information technology carrier, the Electromagnetic Interference and the information divulging question are prominent. The electromagnetic radiation creates mutual interference between electronic products, and also pollutes the human survival environment, harm human health. Therefore the researches on electromagnetic shielding materials is becoming a focusing field , and the demand of electromagnetic shielding fabrics is getting more and more.In this paper, the major work is to prepare graphite electromagnetic shielding coating, nickel electromagnetic shielding coating, as well as mulriple electromagnetic shielding coating on fabrics, the preparation and properties are studied. Through the research on electric conductivity, the content of conductive fillings, the type and the conten of assistant, the type of fabric are obtained. With the best electric conductivity, three kinds of shielding coatings are prepared, which are graphite shielding coatings, nickel shielding coatings, and silver shielding coatings. Coating method is used in electromagnetic shielding fabrics.These electromagnetic shielding fabrics are: graphite shielding coating fabrics, nickel shielding coating fabrics with assistant B, nickel shielding coating fabrics with assistant C, nickel shielding coating fabrics with assistant C( which has two-sided shielding coatings), two kinds of nickel and conductive PET shielding coating fabrics with assistant C(the treatments of conductive PET fabrics are different), graphite and nickel blended shielding coating fabrics, graphite/nickel mulriple shielding coating fabrics, graphite/silver/graphite, and nickel/graphite/nickel mulriple shielding coating fabrics with sandwich type.The results showed that nickel shielding coating fabrics with assistant C(which has two-sided shielding coatings) has the best shielding effective, from 62.0dB to 47.1dB at the range of 30MHz to 1500MHz, the shielding rate is 99.92% to 99.56%, and the fabric has a soft hand feeling. On the other hand, because of the absorption and reflection of conductive PET fabrics on electromagnetic wave, the shielding effective curves of nickel and conductive PET fabrics shielding coating fabrics with assistant C are smooth, from 37.0dB to 37.5dB at the range of 30MHz to 1500MHz, the shielding rate is 98.59% to 98.67%,with no declining trend. Thus the application scope has increased.During the experiment, water-borne coatings are used. It meets the requirements of environmental protection. Preapared shielding coating fabrics with coating method, has many advantages, for example, easy to process, easy to adjust electrical conductivity, low cost, and can be coated large area easily and so on. It will have widespread application foreground .
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