PURPOSE: To remarkably enhance a thermal deformation restricting effect of a shadow mask by laminating a coating film made of a black inorganic pigment exclusive of carbon and graphite on a coat including mainly a specific mixture formed on a shadow mask material.
CONSTITUTION: Aheat radiating film 3 made of a black inorganic pigment exclusive of carbon and graphite is laminated on an anti-doming film 2 including mainly a mixture of Bi2O3, Bi12SiO20, Bi12GeO20, Bi12TiO20, Bi2O3 and Bi12SiO20, a mixture of Bi2O3 and Bi12GeO20, or a mixture of Bi2O3 and Bi12TiO20 formed on a shadow mask material 1, thus obtaining a shadow mask for a cathode-ray tube. The anti-doming film 2 has the function of reflecting an electron beam with an effect of 30%. The heat radiating film 3 is adapted to prevent an increase in temperature of the shadow mask due to heat radiation, thus enhancing the effect by about 20%. Therefore, an anti-doming effect becomes 50% (30%+20%), namely, enhanced by about 70% compared with conventional shadow masks.
KOITABASHI MASAYASU
WATANABE TETSUYA
YAMAMOTO MORIO
