Abstract:
A single-component, yellow-emitting electroluminescent phosphor, a method for making same, and an electroluminescent lamp containing same, are described. The phosphor produces a yellow emission having an x color coordinate from 0.420 and 0.500 and y color coordinate from 0.420 and 0.460 when stimulated by an electric field.
Abstract:
A copper activated zinc sulfide electroluminescent phosphor is disclosed, wherein the phosphor comprises greater than about 1,000 ppm copper. Also disclosed is a copper activated zinc sulfide electroluminescent phosphor having a y color coordinate of at least about 0.480. A method for preparing the copper activated zinc sulfide electroluminescent phosphor is disclosed, comprising contacting a zinc sulfide, a first copper source, a magnesium source, and a lithium halide to form a first mixture; heating the mixture at a temperature and for a time sufficient to form a fired mixture; subjecting the fired mixture to a shear force capable of inducing a plurality of defects in the zinc sulfide lattice structure; and then contacting the fired mixture with a second copper source and a zinc oxide to form a second mixture; heating the second mixture at a temperature and for a time sufficient to form a second-fired material.
Abstract:
An electroluminescent phosphor comprising ZnS:Mn is disclosed. Also disclosed are ZnS:Mn electroluminescent phosphors that are free of or substantially free of copper, and/or wherein the phosphor has a D50 size of less than about 5 μm. In addition, a method for preparing a ZnS:Mn phosphor is disclosed, comprising the steps of contacting at least a portion of each of a first solution comprising a Zn2+ compound, a manganese source, and a second solution comprising a S2− source agent; and then heating the mixture at a temperature and for a time sufficient to form a phosphor.
Abstract:
An electroluminescent phosphor comprising ZnS:Mn is disclosed. Also disclosed are ZnS:Mn electroluminescent phosphors that are free of or substantially free of copper, and/or wherein the phosphor has a D50 size of less than about 5 μm. In addition, a method for preparing a ZnS:Mn phosphor is disclosed, comprising the steps of contacting at least a portion of each of a first solution comprising a Zn2+ compound, a manganese source, and a second solution comprising a S2− source agent; and then heating the mixture at a temperature and for a time sufficient to form a phosphor.
Abstract:
A single-component white-emitting electroluminescent phosphor and its method of making are described. The single-component phosphor exhibits a white emission having an x color coordinate of 0.23 to 0.41 and a y color coordinate of 0.25 to 0.42. The phosphor is comprised of zinc sulfide activated with copper, manganese, chlorine, and, optionally, one or more metals selected from gold and antimony.
Abstract:
An electroluminescent phosphor powder includes copper-activated zinc sulfide particles that have a size distribution with a D50 value of no more than 10 μm, where no more than 25% of the particles have a size greater than about 15 μm and/or a 24-hr brightness of at least 15 footlamberts. These particles are made by a method that includes first firing copper-doped zinc sulfide mixed with zinc oxide, sulfur and a chloride-containing flux, rapidly cooling the mixture to below 100° C., and then mulling and second firing the mixture to provide a powder. The powder can then be elutriated to provide the electroluminescent powder with a narrow particle size distribution (more than 90% between about 5 and 15 μm). The elutriating step can be avoided (albeit with a slightly wider size distribution) by more tightly controlling the first firing temperature.
Abstract:
An orange-yellow-emitting zinc sulfide-based electroluminescent phosphor is described wherein the phosphor has a brightness of greater than 10 foot-Lamberts. More particularly, the phosphor has a brightness of at least about 13 foot-Lamberts and an x color coordinate from about 0.51 to about 0.56 and a y color coordinate from about 0.42 to about 0.48. The zinc sulfide phosphor is activated with manganese, copper, chlorine, and a metal selected from gold and antimony.
Abstract:
An electroluminescent phosphor powder includes copper-activated zinc sulfide particles that have a size distribution with a D50 value of no more than 10 μm, where no more than 25% of the particles have a size greater than about 15 μm and/or a 24-hr brightness of at least 15 footlamberts. These particles are made by a method that includes first firing copper-doped zinc sulfide mixed with zinc oxide, sulfur and a chloride-containing flux, rapidly cooling the mixture to below 100° C., and then mulling and second firing the mixture to provide a powder. The powder can then be elutriated to provide the electroluminescent powder with a narrow particle size distribution (more than 90% between about 5 and 15 μm). The elutriating step can be avoided (albeit with a slightly wider size distribution) by more tightly controlling the first firing temperature.
Abstract:
A single-component, yellow-emitting electroluminescent phosphor, a method for making same, and an electroluminescent lamp containing same, are described. The phosphor produces a yellow emission having an x color coordinate from 0.420 to 0.500 and y color coordinate from 0.420 to 0.460 when stimulated by an electric field.