Abstract: Electron tube having an evacuated envelope equipped with an electron emitting cathode, wherein a layer of activated silicon oxide is formed inside the envelope. The activated silicon oxide layer improves the emission life.

Abstract: The shadow mask of a color cathode ray tube is arranged in the vicinity of a phosphor screen. The shadow mask is provided with through-holes that select the electron beams emitted from the electron guns. A layer comprising, as a filler, one or other of a metal, metal oxide, metal carbide, metal nutride, or a mixture of two or more of these, for example zirconium powder and, as a binder, one of an amorphous metal oxide compound, amorphous metal hydroxide compound or a mixture of these, for example silicon oxide, is formed on the surface of the shadow mask. This layer increases thermal radiation of the shadow mask, reduces electron scattering, and raises the residual emissivity.

Abstract: In a color cathode ray tube provided with in-tube metallic members of which the main constituent is iron, such as the shadow mask assembly or inner shield, at least part of the surface of these metallic members is formed with a blackened region. The vicinity of the surface of this blackened region contains Al, Fe and Si, the Si content being selected in the range 1.5 wt % to 30 wt %, preferably 4 wt % to 15 wt %.