Patent ID: 6097144
Filing Date: 2000-08-01
Classification: C03C,H01J

Abstract:
A cathode ray tube envelope possessing improved anti-browning properties comprising a body capable of maintaining a vacuum when used in an operational cathode ray tube; said body including a screen capable of producing visible images, said screen comprising(i) an inner lead-free glass layer which comprises(a) between about 35 and about 70 percent by weight of silica oxide;(b) between about 10 and about 25 percent by weight of boron oxide;(c) between about 5 and about 15 percent by weight of potassium oxide;(d) between about 6 and about 12 percent by weight of barium oxide;(e) up to about 15 percent by weight of zinc oxide;(f) up to about 10 percent by weight of sodium oxide;(g) up to about 10 percent by weight of lithium oxide;(h) up to about 10 percent by weight of strontium oxide;(i) up to about 10 percent by weight of calcium oxide;(j) up to about 10 percent by weight of magnesium oxide;(k) up to about 5 percent by weight of cesium oxide;(l) up to about 5 percent by weight of zirconium oxide; and(ii) an outer lead-containing glass layer.