Electrically conductive coating in cathode ray tube
AssigneeCorning Glass Works
InventorsEllen K. Dominick, Dale R. Wexell
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Abstract
An improved conductive coating for the inner wall of a cathode ray tube is disclosed. The coating consists essentially of 5-25% of at least one of the alkali metal oxides Na.sub.2 O, K.sub.2 O and Li.sub.2 O, 20-80% SiO.sub.2, 2-25% of at least one oxide selected from the group consisting of Ag.sub.2 O, CuO, CdO, CaO, SrO, BaO, CoO, PbO, MgO, HgO, NiO, ZnO, and MnO, 10-50% carbon, and 0-50% of a filler pigment, the total content of silica plus pigment being 45-85%.
Claims8
In a cathode ray tube comprising a glass faceplate upon which a viewing screen is mounted, a glass neck portion within which an electron gun is mounted, and a glass funnel portion having an electrically conductive coating on at least a portion of its inner wall, the improvement comprising a coating mixture fired at 350.degree.-525.degree. C. to a hard, smooth, glassy, electrically conductive coating exhibiting good durability and resistance to weathering, said coating consisting essentially, in weight percent of total solids, of 5-25% total of at least one of the alkali metal oxides Na.sub.2 O, K.sub.2 O, and Li.sub.2 O, 20-80% SiO.sub.2, 2- 25% of at least one oxide selected from the group consisting of Ag.sub.2 O, CuO, CdO, CaO, SrO, BaO, CoO, PbO, MgO, HgO, NiO, ZnO, and MnO, 10-50% carbon, and 0-50% of a filler pigment, the total of silica and pigment being 45-85%.
Dependencies are inferred from the claim text.