Gte Laboratories Incorporated

Gte Products Corporation

Osram Sylvania Inc.

Bjb Gmbh & Co. Kg

Roger B Hunt, Jr

Thomas E Peters

A Gary Sigai

Romano G Pappalardo

Anthony F Kasenga

Albert M Cavallaro

William J Roche

Karl-Wilhelm Vogt

Paul W Salvi

Lawrence L Hope

Markus Pieper

Chung-Nin Chau

Chung-nin Chau

Robert E Levin

Tobias Brown

Dennis S Holt

Michael A Krebs

A phosphor blend for a compact fluorescent lamp is described wherein the phosphor blend comprises a green-emitting Tbphosphor, a YO:Euphosphor, a SrBPO:Euphosphor, a MgGeOF:Mnphosphor, and optionally a BaMgAlO:Euphosphor, wherein the blend contains from 1% to 20% by weight of the SrBPO:Euphosphor and from 5% to 30% by weight of the MgGeOF:Mnphosphor. A compact fluorescent lamp having a phosphor coating containing the phosphor blend produces a light that is perceived as more pleasing than the light produced by standard compact fluorescent lamps.

Phosphor blend for a compact fluorescent lamp and lamp containing same

A lamp base has a projection that carries lamp contacts and has an outer surface formed with retaining formations arrayed with irregular spacing. A socket forms a recess into which the projection can be inserted with play and apertures provided with contacts engageable with the lamp contacts. Retaining formations in the socket fit with the lamp-base retaining formations in only one defined angular alignment of the lamp base and the socket. The projection has a central plug projecting toward the socket and forming a lamp key coded for a predetermined lamp wattage. The socket has a hole corresponding to the plug and itself forming a socket key coded for the maximally admissible lamp wattage for the socket. The lamp base only fits into the socket when the lamp wattage indicated by the lamp key does not exceed the maximally admissible lamp wattage defined by the socket key.

Keyed socket and lamp base

A lamp envelope is provided with an alumina layer and a multilayer phosphor coating on the alumina layer. The phosphor coating includes a top phosphor layer with a first weight percent of rare earth activators and a middle phosphor layer with a second weight percent of rare earth activators. The second weight percent is less than the first weight percent so that a total amount of the activators in the coating is reduced while maintaining a required lamp brightness and color rendering index (CRI). Preferably, the second weight percent is about 50-60% of the first weight percent and the middle layer is about 30-50% of a total weight of the coating so that a total weight of the activators in the coating is no more than about 80% of a weight of the activators in the coating if the first and second weight percents were the same.

Lamp with multi-layer phosphor coating

A fluorescent lamp comprises at least one layer of a four-component phosphor blend for producing visible illumination having a white color. The quad-phosphor blend comprising a first and second red-emitting phosphor component with each red-emitting phosphor component having different visible emission spectrum principally in the 590 to 630 nm wavelength range. A third blue-emitting phosphor component has an emission spectrum principally in the 430 to 490 nm wavelength range. A fourth no-rare-earth green-emitting phosphor component has an emission spectrum principally in the 500 to 570 nm wavelength range. The relative proportions of the phosphor components are such that an enhanced color rendering index is produced as compared to tri-component blends formed from only three of the phosphor components.

Fluorescent lamp with improved phosphor blend

A method is provided whereby high brightness metaborate phosphors are made by milling the reactants in a saturated aqueous solution of magnesia and boric acid prior to firing. The method increases the homogeneity of the fired metaborate phosphor cake and reduces the tendency of the fired cake to stick to the firing boats.

Method of making luminescent metaborates

A fluorescent lamp comprises at least one layer of a quad-phosphor blend for emitting visible illumination having a white color. The quad-phosphor blend comprising a first and second green emitting phosphor component with each green emitting phosphor component having different visible emission spectrum principally in the 520 to 560 nm wavelength range. A third blue emitting phosphor component has an emission spectrum principally in the 440 to 470 nm wavelength range. A fourth red emitting phosphor component has an emission spectrum principally in the 590 to 620 nm wavelength range. The first green emitting phosphor component is a alkaline earth metal activated phosphor and the second green emitting phosphor is a rare earth activated phosphor wherein the relative proportions of the phosphor components are such that an enhanced color rendering index is produced as compared to tri-component blends formed from three of the phosphor components.

A new and improved method of treating a manganese activated zinc silicate phosphor is described. The method comprises heating a manganese activated zinc silicate phosphor powder having cations consisting essentially of zinc, silicon, manganese, and tungsten and having a 350 nm reflectance less than 80% and a 275 nm reflectance greater than 13.5% to a temperature of about 1225.degree. C. in air. The phosphor powder is then cooled to room temperature and wet milled in an acid solution. The phosphor powder is then separated from the acid solution washed in water and dried to form a dry phosphor powder having a 350 nm reflectance equal to or greater than 80% and a 275 nm reflectance equal to or less than 13.5%.

Method for improving a manganese activated zinc silicate phosphor

The lumen maintenance of fluorescent lamps containing yttrium vanadate phosphors is markedly improved by the presence of a protective oxide layer for the phosphor. The protective oxide layer is produced by evaporating aluminum isopropoxide, in a vacuum, over phorphor particles forming a continuous aluminum isopropoxide over the phosphor particles. The isopropoxide coating is subsequently oxidized by lehring the phosphor at a temperature from about 500.degree. C. to 625.degree. C. forming an alumina coating on the phosphor particles.

Method of coating yttrium vanadate phosphors with Al.sub.2 O.sub.3

A method for producing manganese activated zinc silicate phosphor wherein the individual phosphor particles are surrounded with a non-particulate, conformal aluminum oxide coating is disclosed. The method comprises dry blending a mixture of components consisting essentially of zinc oxide, silicic acid, a source of manganese, ammonium chloride, ammonium fluoride, tungstic oxide, and silica, wherein the Zn+Mn/Si mole ratio is from about 1.95 to about 2.02, wherein the silica is colloidal and has a surface area of from about 50 to about 410 m.sup.2 per gram, and wherein the colloidal silica makes up from about 0.01% to about 1.0% by weight of the mixture; firing the resulting dry blend of components in a nitrogen atmosphere at a temperature of from about 1200.degree. C. to about 1300.degree. C. for a sufficient time to produce the phosphor; milling the resulting phosphor for a period of time of from about 60 minutes to about 120 minutes; firing the resulting milled phosphor in air at a temperature of from about 1175.degree. C. to about 1275.degree. C. for a sufficient time to diffuse the tungsten and manganese to the surfaces of the phosphor particles; applying a non-particulate, conformal aluminum oxide coating to the outer surface of individual particles of the phosphor while the phosphor particles are suspended in a fluid bed having a midpoint temperature between 400.degree. and 480.degree. C., the aluminum oxide coating being formed by a chemical vapor deposition reaction involving oxidation of trimethyl aluminum; and annealing the aluminum oxide coated phosphor for a period of time from 4-16 hours at a temperature between 750.degree. and 800.degree. C.

Firing and milling method for producing a manganese activated zinc

A fluorescent lamp containing a Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 coating on a layer of yttrium vanadate phosphor and a method of coating the layer of the yttrium vanadate phosphor with a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 is described. The method comprises applying a coating of a metal, such as yttrium or aluminum, on the yttrium vanadate phosphor then lehring the metallic coating at about 500.degree. C. to about 625.degree. C. to form a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 overlaying the layer of phosphor.

A method of coating a layer of an yttrium vanadate phosphor contained in

A new and improved manganese activated zinc silicate phosphor is described. The phosphor has cations consisting essentially of zinc, silicon, manganese, and tungsten. The phosphor has an absolute reflectance less than or equal to 13.5% at 275 nm, an absolute reflectance equal to or greater than 80% at 350 nm, and a surface area from about 0.3 m.sup.2 /gm to about 0.4 m.sup.2 gm.

Manganese activated zinc silicate phosphor

A manganese activated zinc silicate phosphor and method for producing same is disclosed which comprises dry blending a mixture of components consisting essentially of zinc oxide, silicic acid, a source of manganese, ammonium chloride, ammonium fluoride, tungstic oxide and silica wherein the Zn+Mn/Si mole ratio is from about 1.95 to about 2.02, wherein the silica is colloidal and has a surface area of from about 50 to about 410 m.sup.2 /g, and wherein the colloidal silica makes up from about 0.01% to about 1.0% by weight, firing the blend in a nitrogen atmosphere at a temperature of from about 1200.degree. C. to about 1300.degree. C. for a sufficient time to produce the phosphor, and firing the phosphor in air at a temperature of from about 1175.degree. C. to about 1275.degree. C. for a sufficient time to diffuse the tungsten and manganese to the surfaces of the phosphor particles. Between the firing steps, the phosphor can be milled for from about 60 to 120 minutes to increase luminescence. The phosphor can be coated with a continuous coating of aluminum oxide and annealed to improve maintenance of the phosphor. A fluorescent lamp incorporating the phosphor is also disclosed.

A method for preventing the hydration/solubilization of the protective oxide coating of a phosphor is described. The method involves coating of the oxide coated phosphor particles with a continuous hydrophobic coating. After the phosphor particles are coated with the continuous hydrophobic coating and the continuous hydrophobic coating cured, they are added to a water-based suspension and subsequently processed into a lamp.

Method of treating a coated phosphor

A method for eliminating carbonaceous contaminants and preventing the hydration/solubilization of the oxide coating of a phosphor is described. The method involves the annealing of the oxide coated phosphor at a temperature and for a period sufficient to preclude adversely affecting the protective oxide coating on the phosphor during subsequent water-based suspension processing without detrimentally altering the phosphor. After annealing the phosphor is cooled and then added to a water-based suspension. The optimum conditions for annealing a manganese activated zinc silicate phosphor or a calcium halophosphate phosphor having a protective aluminum oxide coating are the combination of a temperature between about 700.degree. C. and about 850.degree. C. and for a period of time from about 15 minutes to about 20 hours.

Growing community of inventors

Medfield, MA, United States of America

Roger B Hunt, Jr