Resistive electrical conductive coating for use in a cathode ray tube

Claim 1

An improved high resistive electrical conductive composition formulated for application to a defined area of the interior surface of a cathode ray tube envelope during tube fabrication to provide an amorphous deposition thereon, said resistive composition comprising a homogeneous mixture of: substantially 35 to 65 weight percent of a particulate amorphous type vitreous substantially insulative frit material compatible with said tube environment and having a softening point in the temperature range of substantially 350° C. to 450° C., said frit material being comprised principally of substantially 70 to 85 weight percent of PbO, 5 to 15 weight percent of B 2 O 3 , 2 to 10 weight percent of Al 2 O 3 , and 3 to 5 weight percent of SiO 2 , said frit material having a particle size averaging within the range of substantially 1.0 to 35.0 microns; substantially 65 to 35 weight percent of at least one particulate material selected from the group consisting essentially of cadmium oxide, indium oxide and copper oxide homogeneously admixed with said frit, said metal oxide ingredients having a distribution of particles averaging within the range of substantially 1.0 to 10.0 microns in size; binder solids within the range of substantially 0.1 to 0.5 weight percent; and solvent means for binder solids, said solvent means being compatible with said tube environment and of a quantity to provide a dispersing medium for said mixture and to impart a viscosity thereto of a value within the range of substantially 150 to 1000 centipoise.