For numerous carbon based materials used as coatings of cathode ray tube, the gas desorption properties were examined by using a technique of thermal desorption spectroscopy. The major outgassing species were CO2 and H2O. The peak temperature of the desorption was 373-473 K. The desorption amount was very small for the material with TiO2 powder and water glass, and large for the material with graphite powder. The baking temperature required for reduction of the gas desorption amount is 673-773 K. Gas adsorption experiments were also conducted. The adsorption amounts of H2O or CO2 increased with the composition ratio of graphite powder. In particular, the gas adsorption capability was largely increased by addition of TiO2 powder. This enhancement was caused by the fact that the porosity of surface structure and the effective surface area were increased by the addition of TiO2 powder.