RADIO WAVE ABSORBING BODY

PROBLEM TO BE SOLVED: To provide a radio wave absorbing body small in change of radio wave absorption by composing a carbon fiber bundle of the specified number of carbon long fibers and forming a water-proof layer on the surface. SOLUTION: A number of carbon long fibers of large volumetric inherent electric resistance are arranged in the direction of length, and bonded by a bonding agent to make a long carbon fiber bundle, which is spacedly disposed in parallel to make a radio wave absorbing layer. In addition, a dielectric layer is formed therebehind, and a reflection layer is formed behind the dielectric to make a radio wave absorbing body. In this case, it is composed of at least the 1000 carbon long fibers as the carbon fiber bundle used for forming the radio wave absorbing layer, and the radio wave absorbing body having a water- proof layer on the surface is used. Thereby even if water invades from the defect part of the water-proof layer and the end of the carbon fiber bundle, scattering into the carbon fiber inside can be suppressed to the minimum. Thus, lowering of radio wave characteristics of the radio wave absorbing body due to incursion of water can be prevented.