PURPOSE: To stabilize a shape and improve heat insulation, heat retaining property hygroscopicity, and deodorizing property by mixing synthetic resin and carbon fiber so as to be a flat sheet-state body, and heat-sealing several parts of the sheet-state body in a thickness direction.

CONSTITUTION: Synthetic resin and carbon fiber are mixed to be a flat sheet- state body. Several parts of the sheet-state body are heat-sealed 3 in a thickness direction to obtain a desired plate-state body 1. This enables the plate-state body 1 to have heat resistance and high heat insulation and high heat retaining property, to be useful in energy saving, to absorb and accumulate surplus humidity, and to discharge the surplus humidity spontaneously at the time of low temperature. Moreover absorption of odor and gradual diffusion of once absorbed odor is also possible.