Patent ID: 6010779
Filing Date: 2000-01-04
Classification: C09K,H01J,Y10T

Abstract:
A display screen having a phosphor coating comprising a phosphor provided with a coating which comprises colloidal SiO.sub.2 particles and at least one oxygen compound of an element selected from the group consisting of zinc, aluminum, magnesium, calcium and barium, in a molar ratio of the SiO.sub.2 particles to the at least one oxygen compound of from 5:1 to 30.1, characterized in that the colloidal SiO.sub.2 particles are composed of SiO.sub.2 particles having an average particle size of 4 nm.ltoreq.d.ltoreq.30 nm corresponding to a specific surface of 100 m.sup.2 /g.ltoreq.A.sub.s .ltoreq.550 m.sup.2 /g, and SiO.sub.2 particles having an average particle size of 50 nm.ltoreq.d.ltoreq.150 nm, corresponding to a specific surface of 25 m.sup.2 /g.ltoreq.A.sub.s .ltoreq.70 m.sup.2 /g.