摘要 |
A foam absorber having electromagnetic energy attenuation characteristics comprising an open cell reticulated polyurethane foam impregnated with a conductive ink applied to a surface of the foam substrate. The conductive ink is applied as by spraying to a surface of the foam, coating such surface and gradiently loading the foam with the ink by penetration of the ink in gradually decreasing amount into the foam to a final depth therein. The conductive ink is comprised of an epoxy resin carrier and a combination of carbon and a metal such as silver, copper or nickel, preferably silver. The ink is applied as a curable mixture containing a solvent, to the foam substrate, the solvent is evaporated following coating and penetration of the ink into the foam, and the epoxy carrier of the ink in the foam substrate is cured.
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