Abstract: A method for preparing a specific zinc orthosilicate phosphor particle having a nonparticulate, conformal aluminum oxide coating wherein all of a manganese activator is present as manganese (II) and occupies zinc (II) sites includes the steps of blending a zinc source, a manganese (II) source, a silicon source, and a tungsten source in amounts in accordance with said formula with an amount of up to about 2 weight percent NH.sub.4 Cl and up to about 0.2 weight percent NH.sub.

Abstract: A manganese-activated zinc orthosilicate phosphor having the empirical formula:Zn.sub.(2.00-x-y) Mn.sub.x SiO.sub.(4.00-y) (WO.sub.3).sub.zwherein:0.04.ltoreq.x.ltoreq.0.15;0.ltoreq.y.ltoreq.0.05; and0.ltoreq.z.ltoreq.0.002is provided. A method for preparing the above described phosphor is also disclosed. The method comprises blending a method for preparing manganese-activated zinc orthosilicate phosphor having the empirical formula:Zn.sub.(2.00-x-y) Mn.sub.x SiO.sub.(4.00-y) (WO.sub.3).sub.zwherein:0.04.ltoreq.x.ltoreq.0.15;0.ltoreq.y.ltoreq.0.05; and0.ltoreq.z.ltoreq.0.002;the method comprising: blending a zinc source, a manganese (II) source, a silicon source, and a tungsten source in amounts in accordance with the formula together with up to about 2 weight percent NH.sub.4 Cl and up to about 0.2 weight percent NH.sub.

Abstract: The red and blue color cathode ray tube phosphors for color television are pigmented with a coating of an aqueous-insoluble silicate-based glass matrix containing pigment particles. When incorporated into a tridot color cathode ray tube, the contrast of the tube is improved. The coated particles are formed by dispersing the particles in a slurry with a silicate, the pigment particles and an optional wetting agent, and evaporating the slurry to dryness. The dried coated particles are then heated in order to insolubilize the glass matrix, and soluble ions are then removed by washing.

Abstract: A green emitting ZnS : Cu, Al cathodoluminescent phosphor having x and y coordinate values of from 0.250 to 0.280 and 0.560 to 0.615 respectively, is produced by a critical firing schedule exemplified by slow heating to about 1000.degree. C, soaking at this temperature for about 1 hour, followed by slow cooling at about 3.degree. C per minute to 700.degree. C, followed by air quenching. The phosphor is useful for example, in tri-color television color television cathode ray tube.