Granted Patent B1

US 8,057,706 · App. 12/843,947 · Granted Nov 15, 2011

Abstract

Claims (66)

1. A phosphor material comprising individual particles of manganese (Mn 4+ ) doped fluoride phosphor, wherein each particle is encapsulated with a layer of a manganese-free fluoride phosphor.

2. The phosphor material of claim 1 , wherein the Mn 4+ (manganese) doped fluoride phosphor is a material comprising at least one of:

(A) A 2 [MF 6 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and M is selected from Ge, Si, Sn, Ti, Zr, Hf and combinations thereof;

(B) A 2 [MF 5 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc and combinations thereof;

(C) E[MF 6 ]:Mn 4+ , where E is selected from Mg, Ca, Sr, Ba, Zn, and combinations thereof; and where M is selected from Ge, Si, Sn, Ti, Zr, Hf and combinations thereof;

(D) A 3 [MF 6 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc, Y, La, a lanthanide, Bi, and combinations thereof;

(E) A 2 [MF 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Nb, Ta, and combinations thereof;

(F) Zn 2 [MF 7 ]:Mn 4+ , where M is selected from Al, Ga, In, and combinations thereof;

(G) Ba 0.65 Zr 0.35 F 2.7 :Mn 4+ ;

(H) A[In 2 F 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 and combinations thereof; or

(I) A 3 [MF 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof, and where M is selected from Zr, Si, Ge, Sn, Ti, and Hf and combinations there of.

3. The phosphor material of claim 1 , wherein the manganese-free fluoride phosphor is a material comprising at least one of:

(A) A 2 [MF 6 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and M is selected from Ge, Si, Sn, Ti, Zr, and combinations thereof;

(B) A 2 [MF 5 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, and combinations thereof;

(C) E[MF 6 ], where E is selected from Mg, Ca, Sr, Ba, Zn, and combinations thereof; and where M is selected from Ge, Si, Sn, Ti, Zr, and combinations thereof;

(D) A 3 [MF 6 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc, Y, La, a lanthanide, Bi, and combinations thereof;

(E) A 2 [MF 7 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Nb, Ta, and combinations thereof;

(F) Zn 2 [MF 7 ], where M is selected from Al, Ga, In, and combinations thereof;

(G) Ba 0.65 Zr 0.35 F 2.7 ;

(H) A[In 2 F 7 ], where A is selected from Li, Na, K, Rb, Cs, NH4 and combinations thereof; or

(I) A 3 [MF 7 ], where A is selected from Li, Na, K, Rb, Cs, NH4, and combinations thereof, and where M is selected from Zr, Si, Ge, Sn, Ti, and Hf and combinations there of.

4. A lighting apparatus, comprising:

a light source; and

a phosphor material radiationally coupled to the light source, and comprising individual particles of Mn 4+ (manganese) doped fluoride phosphor, wherein each particle is encapsulated with a manganese-free layer of the fluoride phosphor.

5. The lighting apparatus of claim 4 , wherein the Mn 4+ (manganese) doped fluoride phosphor is a material comprising at least one of:

(A) A 2 [MF 6 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and M is selected from Ge, Si, Sn, Ti, Zr, Hf and combinations thereof;

(B) A 2 [MF 5 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc and combinations thereof;

(C) E[MF 6 ]:Mn 4+ , where E is selected from Mg, Ca, Sr, Ba, Zn, and combinations thereof; and where M is selected from Ga, Si, Sn, Ti, Zr, Hf and combinations thereof;

(D) A 3 [MF 6 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc, Y, La, a lanthanide, Bi, and combinations thereof;

(E) A 2 [MF 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Nb, Ta, and combinations thereof;

(F) Zn 2 [MF 7 ]:Mn 4+ , where M is selected from Al, Ga, In, and combinations thereof;

(G) Ba 0.65 Zr 0.35 F 2.7 :Mn 4+ ;

(H) A[In 2 F 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH4 and combinations thereof; or

(I) A 3 [MF 7 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, NH4, and combinations thereof, and where M is selected from Zr, Si, Ge, Sn, Ti, and Hf and combinations thereof.

6. The lighting apparatus of claim 4 , wherein the manganese-free fluoride phosphor is a material comprising at least one of:

(A) A2[MF6], where A is selected from Li, Na, K, Rb, Cs, NH4, and combinations thereof; and M is selected from Ge, Si, Sn, Ti, Zr, and combinations thereof;

(B) A 2 [MF 5 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, and combinations thereof;

(C) E[MF 6 ], where E is selected from Mg, Ca, Sr, Ba, Zn, and combinations thereof; and where M is selected from Ge, Si, Sn, Ti, Zr, and combinations thereof;

(D) A 3 [MF 6 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Al, Ga, In, Sc, Y, La, a lanthanide, Bi, and combinations thereof;

(E) A 2 [MF 7 ], where A is selected from Li, Na, K, Rb, Cs, NH 4 , and combinations thereof; and where M is selected from Nb, Ta, and combinations thereof;

(F) Zn 2 [MF 7 ], where M is selected from Al, Ga, In, and combinations thereof;

(G) Ba 0.65 Zr 0.35 F 2.7 ;

(H) A[In 2 F 7 ], where A is selected from Li, Na, K, Rb, Cs, NH4 and combinations thereof; or

(I) A 3 [MF 7 ], where A is selected from Li, Na, K, Rb, Cs, NH4, and combinations thereof, and where M is selected from Zr, Si, Ge, Sn, Ti, and Hf and combinations there of.

7. The fighting apparatus of claim 4 , wherein the light source is a semiconductor light emitting diode (LED) which emits radiation having a peak wavelength in the range of from about 370 to about 500 nm.

8. The lighting apparatus of claim 7 , wherein the semiconductor light emitting diode comprises a nitride represented by the formula In i Ga j Al k N, where 0≦i, 0≦j, 0≦k and l+j+k=1.

9. The lighting apparatus of claim 4 , wherein the light source is an organic emissive structure.

10. The lighting apparatus of claim 4 , further comprising an encapsulant material surrounding the light source and the phosphor material within a housing.

11. The lighting apparatus of claim 10 , wherein the encapsulant material comprises at least one silicone or epoxy material.

12. The lighting apparatus of claim 10 , wherein the phosphor material is deposited on a surface of the light source.

13. The lighting apparatus of claim 10 , wherein the phosphor material is dispersed in the encapsulant material.

14. The lighting apparatus of claim 10 , wherein the phosphor material is deposited on a surface of the housing.

15. The lighting apparatus of claim 4 , further comprising a reflective cup, wherein the light source is mounted in the reflective cup.

16. The lighting apparatus of claim 4 , wherein the phosphor material further comprises one or more additional phosphors.

17. The lighting apparatus of claim 16 , wherein at least one of the additional phosphors has an emission maximum in the range of about 430 to about 500 nm.

18. The lighting apparatus of claim 16 , wherein at least one of the additional phosphors has an emission maximum in the range of about 500 to about 630 nm.

19. The lighting apparatus of claim 16 , wherein at least one of the additional phosphors is a garnet activated with Ce 3+ ; an alkaline earth orthosilicate activated with Eu 2+ ; or (Sr,Ca,Ba) 3 (Si,Al)O 4 (F,O) activated with Ce 3+ .

20. The lighting apparatus of claim 16 , characterized by the ability to produce white light.

21. A method of encapsulating manganese-doped fluoride phosphor particles, comprising:

(a) preparing a saturated solution of a manganese-free fluoride phosphor;

(b) mixing the saturated solution with manganese-doped fluoride phosphor powder in a vessel to form a suspension;

(c) evaporating the suspension until a paste is formed; and

(d) drying the paste so as to produce a powder comprising encapsulated particles.

22. The method of claim 21 , wherein the saturated solution is prepared in an acid which comprises at least one of HF, NH 4 HF 2 , or NH 4 F.

23. The method of claim 21 , wherein mixing comprises pouring the saturated solution onto manganese-doped fluoride phosphor powder in the vessel with continuous stirring.

24. The method of claim 21 , wherein the paste is dried in a dry-box atmosphere at about 10 degrees Celsius to about 300 degrees Celsius.

Assignments (11)