Phosphors containing oxides of alkaline-earth and Group-IIIB metals and light sources incorporating the same

A phosphor blend comprising:

• (a) a first phosphor comprising oxides of at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof and oxides of at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combination thereof, said phosphor being activated with ions of at least a rare-earth metal comprising at least europium, said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<y<1 and 1<y<1.1;
• and
• (b) at least an additional phosphor selected from the group consisting of phosphors that are excitable by radiation having wavelengths in a range from about 315 nm to about 480 nm that have a peak emission in at least one of blue, blue-green, green, yellow-orange, and red light wavelengths.

A method for producing a phosphor, said method comprising:

• (a) providing amounts of oxygen-containing compounds of at least a rare-earth metals comprising at least europium;
• at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof;
• and at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combinations thereof;
• (b) mixing together said oxygen-containing compounds to form a mixture;
• and
• (c) firing said mixture in a reducing atmosphere at a temperature and for a time sufficient to convert said mixture to said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<y<1 and 1<y<1.1.

A method for producing a phosphor, said method comprising:

• (a) providing amounts of compounds of at least a rare-earth metals comprising at least europium;
• at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof, and at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combinations thereof;
• (b) mixing together said compounds to form a mixture;
• (c) heating said mixture to convert said mixture to a mixture of oxides;
• and
• (d) firing said mixture of oxides in a reducing atmosphere at a temperature and for a time sufficient to convert said mixture to said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<y<1 and 1<y<1.1.

A method for producing a phosphor, said method comprising:

• (a) providing a first solution comprising compounds of at least a rare-earth metals comprising at least europium;
• at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof;
• and at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combinations thereof, said compounds being selected from the group consisting of nitrates, sulfates, acetates, citrates, chlorates, perchlorates, oxyhalides, salts of organic acids containing 1 to 6 carbon atoms, esters of di-carboxylic acids containing 1 to 6 carbon atoms, salts of aromatic acids having 1 to 2 aromatic rings, acetylacetonates, alkoxides, phenoxides, and mixtures thereof;
• (b) providing a second solution comprising a material selected from the group consisting of ammonium hydroxide, ammonium carbonate, ammonium oxalate, methanolamine, ethanolamine, propanolamine, dimethanolamine, diethanolamine, dipropanolamine, trimethanolamine, triethanolamine, or tripropanolamine, and mixtures thereof;
• (c) adding said second solution to said first solution to form a precipitate;
• and
• (d) firing said precipitate in a reducing atmosphere at a temperature and for a time sufficient to convert said mixture to said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<y<1 and 1<y<1.1.

A light source comprising:

• (a) at least one LED that is capable of emitting a radiation having wavelengths in a range from about 315 nm to about 480 nm;
• and
• (b) a phosphor casting comprising a transparent material and particles of a phosphor blend comprising:
• (1) a first phosphor comprising oxides of at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof and oxides of at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combination thereof, said phosphor being activated with ions of at least a rare-earth metal comprising at least europium, said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<y<1 and 1<y<1.1;
• and
• (2) at least an additional phosphor selected from the group consisting of phosphors that are excitable by radiation having wavelengths in a range from about 315 nm to about 480 nm that have a peak emission in at least one of blue, blue-green, green, yellow-orange, and red light wavelengths.

A light source comprising:

• (a) a plurality of LEDs attached to a reflective panel, said LEDs being capable of emitting a radiation having wavelengths in a range from about 315 nm to about 480 nm;
• and
• (b) a phosphor coating comprising a polymeric binder and particles of a phosphor blend dispersed therein, said coating being disposed in a direction of radiation emitted from said LEDs, said phosphor blend comprising:
• (1) a first phosphor comprising oxides of at least an alkaline-earth metal selected from the group consisting of strontium, barium, calcium, and combinations thereof and oxides of at least a Group-IIIB metal selected from the group consisting of aluminum, gallium, indium, and combination thereof, said phosphor being activated with ions of at least a rare-earth metal comprising at least europium, said phosphor having a formula of
• (M1−xREx)yD2O4;
• wherein M is said at least an alkaline-earth metal;
• RE is said rare-earth metal comprising at least europium;
• D is said at least a Group IIIB metal;
• 0.001<x<0.3, and y satisfies a condition selected from the group consisting of 0.75<Y<1 and 1<y<1.1;
• and
• (2) at least an additional phosphor selected from the group consisting of phosphors that are excitable by radiation having wavelengths in a range from about 315 nm to about 480 nm that have a peak emission in at least one of blue, blue-green, green, yellow-orange, and red light wavelengths.