Granted Patent B2

US 9,567,516 · App. 14/303,020 · Granted Feb 14, 2017

Abstract

Claims (32)

1. A process for synthesizing a manganese doped phosphor, the process comprising:

dry milling particles of a phosphor precursor of formula I; and

A x [MF y ]:Mn 4+   (I)

contacting the dry milled particles with a fluorine-containing oxidizing agent in gaseous form at an elevated temperature, the fluorine-containing oxidizing agent comprising F 2 , SF 6 , BrF 5 , NH 4 HF 2 , NH 4 F, KF, AlF 3 , SbF 5 , ClF 3 , BrF 3 , KrF, XeF 2 , XeF 4 , NF 3 , SiF 4 , PbF 2 , ZnF 2 , SnF 2 , CdF 2 or combinations thereof; and

wherein,

A is Li, Na, K, Rb, Cs, or a combination thereof;

M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof;

x is 1, 2, or 3 and is equal to the absolute value of the charge of the [MF y ] ion;

y is 5, 6 or 7.

2. The process according to claim 1 , wherein M is Si, Ge, Sn, Ti, Zr, or a combination thereof.

3. The process according to claim 1 , wherein the particles of the phosphor precursor of formula I have a particle size distribution of a D50 value less than about 30 microns after the dry milling step.

4. The process according to claim 1 , wherein the particles of the phosphor precursor of formula I have a particle size distribution of a D50 value ranging from about 10 microns to about 25 microns after the dry milling step.

5. The process according to claim 1 , wherein the fluorine-containing oxidizing agent comprises F 2 .

6. The process according to claim 1 , wherein the dry milled particles are contacted with the fluorine-containing oxidizing agent at a temperature in a range from about 500° C. to about 600° C.

7. The process according to claim 1 , wherein the dry milled particles are contacted with the fluorine-containing oxidizing agent for at least four hours.

8. The process according to claim 1 , additionally comprising contacting the dry milled particles with a saturated solution of a compound of formula II in aqueous hydrofluoric acid after contacting the dry milled particles with the fluorine-containing oxidizing agent

A x [MF y ]  (II).

9. The process according to claim 1 , wherein

A is Na, K, Rb, Cs, or a combination thereof;

M is Si, Ge, Ti, or a combination thereof; and Y is 6.

10. The process according to claim 1 , wherein the phosphor precursor is K 2 SiF 6 :Mn 4+ .

11. A process for synthesizing a manganese doped phosphor, the process comprising:

dry milling particles of a phosphor precursor, wherein the precursor is selected from the group consisting of

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

(B) A 3 [MF 6 ]:Mn 4+ , where A is selected from Li, Na, K, Rb, Cs, and combinations thereof; and where M is selected from Al, Ga, In, and combinations thereof;

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

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

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

(F) 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, and combinations thereof;

(G) Ba 0.65 Zr 0.35 F 2.70 :Mn 4+ ; and

(H) A 3 [ZrF 7 ]:Mn 4+ where A is selected from Li, Na, K, Rb, Cs and combinations thereof, and

contacting the dry milled particles with a fluorine-containing oxidizing agent in gaseous form at an elevated temperature, the fluorine-containing oxidizing agent comprising F 2 , SF 6 , BrF 5 , NH 4 HF 2 , NH 4 F, KF, AlF 3 , SbF 5 , ClF 3 , BrF 3 , KrF, XeF 2 , XeF 4 , NF 3 , SiF 4 , PbF 2 , ZnF 2 , SnF 2 , CdF 2 or combinations thereof.

Assignments (11)