PURPOSE: To enable to obtain electromagnetic wave absorbing sheet material having flexibility, air permeability, light weight, and durability by a method wherein the surface of a conductive fibric material is coated with an electromagnetic wave absorbing material containing ferromagnetic powder and an organic polyer compound as the main constituents.
CONSTITUTION: An electromagnetic wave absorbing layer 2 is formed by the coat of the surface of the conductive fibric material 3 with the electromagnetic wave absorbing material contaning ferromagnetic powder and an organic polymer compound as the main constituent to a desired thickness. In this case, according to the wavelength of electromagnetic waves to be absorbed, it is not always necessary to coat the entire surface with the absorbing material. The coat of the material 3 with said absorbing material in the form of lattice, mesh, perforation, and the like makes the great effect by the economization, reduction in weight, and increase in air permeability of the absorbing material. To obtain a thickness of over a fixed value, hardening a resin after an expanding agent is mixed in the composition of the aborbing layer and then expanded enables to obtain a thick electromagnetic wave absorbing layer.
NOHATA ATSUO
HASEGAWA SHIYUUICHI
OKAYASU SHINPEI
