Manufacturing method of electromagnetic waves shielding and absorption material and electromagnetic waves shielding and absorption material thereby and sheet with the same

摘要

The present invention relates to a manufacturing method of an electromagnetic wave shielding and absorbing material which is excellent in electromagnetic wave shielding and absorbing abilities and has high strength, an electromagnetic wave shielding and absorbing material manufactured therefrom, and an electromagnetic wave shielding and absorbing composite sheet including the same. The method comprises the following steps: preparing A) an isocyanate mixed solution and B) a polyol mixed solution; injecting A) the isocyanate mixed solution and B) the polyol mixed solution into a mold and foaming the same; and removing urethane organic matter, crystallizing the remaining inorganic matter, and sintering at the high temperature. To A) the isocyanate mixed solution, isocyanate, ceramic mixed powder, electromagnetic wave shielding and absorbing powder, and a dispersant are added and mixed. To B) the polyol mixed solution, polyol, ceramic mixed powder, electromagnetic wave shielding and absorbing powder, a crosslinking agent, a dispersant, a foaming agent, and a surfactant are added and mixed.