SCANDATE IMPREGNATION TYPE CATHODE AND MANUFACTURE OF CATHODE-RAY TUBE USING IT

PROBLEM TO BE SOLVED: To provide a scandate impregnation type cathode having a coating film in which the breakage and contamination of the coating film hardly occurs, and provide a manufacturing method for a cathode-ray tube using it. SOLUTION: A coating film 1 is formed of nickel and scandium oxide, the product of Sc/Ni element ratio and coating film thickness (unit:nm) of the coating film 1 is set to one or more and less than 20, and film thickness, 100nm or more. The nickel is evaporated by heating at 1050 deg.C to 1200 deg.C after the vacuum exhaust process of a cathode-ray tube. Thereby, since the film is sufficiently thick before the heating of a cathode, the breakage of the coating film hardly occurs, and also the contamination hardly occurs. After the evaporation of the nickel, thin scandium oxide is left on the surface of the cathode so as to obtain an excellent electron emission characteristic.