Abstract: A process is disclosed for bonding pigment particles to phosphor particles. The process involves forming a relatively uniform blend of a phosphor, one or more pigments, colloidal silicon dioxide, and water, with the amount of water in the blend being no greater than about 10% by weight, and heating the blend at a temperature of at least about 150.degree. C. to produce a pigmented phosphor having an overcoating of silicon dioxide.

Abstract: A catholuminescent material consisting essentially of particles of copper-activated zinc sulfide cathodoluminescent phosphor having at least a partial coating of a mixture of a blue pigment of cobalt aluminate and a red pigment of iron oxide wherein the weight ratio of said blue pigment to said red pigment is from about 3.5:1 to about 4.5:1 and the weight percent of said pigments are from about 0.2% to about 2% by weight of catholuminescent phosphor. A process for producing said pigmented phosphor comprises forming the appropriate aqueous slurries by proper pH control and then by the addition of collodial silica, the pigment is coated onto the phosphor particles.

Abstract: A pigmented silicate coated phosphor is disclosed and a process for producing the phosphor. The process involves preparing a relatively uniform aqueous mixture of particles of a phosphor, particles of a deagglomerated pigment, and a free flowing agent and then adding a precipitating agent to the mixture in an amount sufficient to cause the free flowing agent and pigment to co-precipitate upon and coat the phosphor, followed by separating the pigmented phosphor from the resulting liquor. A relatively uniform mixture is formed of the resulting dried phosphor, a water soluble silicate, and water the water being in an amount of sufficient to allow the silicate to coat the surface of the phosphor particles. The mixture is heated at a sufficient temperature for a sufficient time with sufficient agitation to produce the final non-agglomerated silicate coated pigmented phosphor.

Abstract: A catholuminescent material consisting essentially of particles of copper-activated zinc sulfide cathodoluminescent phosphor having at least a partial coating of a mixture of a blue pigment of cobalt aluminate and a red pigment of iron oxide wherein the weight ratio of said blue pigment to said red pigment is from about 3.5:1 to about 4.5:1 and the weight percent of said pigments are from about 0.2% to about 2% by weight of catholuminescent phosphor. A process for producing said pigmented phosphor comprises forming the appropriate aqueous slurries by proper pH control and then by the addition of colloidal silica, the pigment is coated onto the phosphor particles.

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: Cathode ray phosphor compositions that are resistant to photodeposition slurries consist essentially of discrete particles of a phosphor material having a core of silver-activated zinc sulfide and a coating over a substantial amount of the external surfaces of a composition represented by the formula, Mg.sub.2 P.sub.2 O.sub.7 :Al.sub.4 (P.sub.2 O.sub.7).sub.3 . xSiO.sub.2 wherein the coating is at a sufficient level on the surfaces to provide a PO.sub.4 content of the composition of from about 0.05% to about 0.2% by weight and the SiO.sub.2 content sufficient to impart flowability. The coating composition is formed by a slurry process that enables a uniform and adherent coating to be deposited on the surfaces of the particles of silver-activated zinc sulfide.