IP Library Granted Patent US 9,399,731
Granted Patent B2
US 9,399,731 · App. 13/991,860 · Granted Jul 26, 2016

Phosphor, method for producing the same, and luminescent device using the same

Inventors: Go Takeda (Tokyo, JP); Ryo Yoshimatsu (Tokyo, JP); Naoto Hirosaki (Tsukuba, JP)
Assignee: DENKA COMPANY LIMITED
C09K11/0883C04B35/597C04B35/6268C09K11/7734H05B33/14C04B2235/3213C04B2235/3215C04B2235/3217C04B2235/3224C04B2235/3418C04B2235/3817C04B2235/3852C04B2235/3865C04B2235/3873C04B2235/3891C04B2235/402C04B2235/428
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Quick Facts
Patent No.
US 9,399,731
App. No.
13/991,860
Granted
Jul 26, 2016
Kind
B2
Abstract

A blue phosphor having an emission peak wavelength different from that of conventional blue phosphors, a method for producing the same, and a high-intensity luminescent device using the phosphor are provided. The phosphor of the present invention is represented by a general formula Me a Re b Al c Si d O e N f (Me may contain one or more elements selected from Mg, Ca, Sc, Y, and La as second elements, provided that Sr or Ba is contained as an essential first element, and Re may contain one or more elements selected from Mn, Ce, Tb, Yb, and Sm as second elements, provided that Eu is contained as an essential first element), where the composition ratio represented by a, b, c, d, e, and f has the following relations: a+b=1, 0.005<b<0.25, 1.60<c<2.60, 2.50<d<4.05, 3.05<e<5.00, and 2.75<f<4.40.

Claims (39)

1. A phosphor represented by a general formula Me a Re b Al c Si d O e N f (Me contains one or more elements selected from Sr and Ba, and Re contains Eu),

wherein the composition ratio represented by a, b, c, d, e, and f has the following relations:

a+b= 1,

0.005< b< 0.25,

1.60< c< 2.60,

2.45< d< 4.05,

3.05< e< 5.00, and

2.75< f< 4.40:

wherein the ratio of c/d and e/f have the following relationships:

0.610< c/d< 0.690,1.00< e/f< 1.450, or

0.620< c/d< 0.675,1.007< e/f< 1.320, and

wherein the phosphor is excited by light having wavelengths falling within a range from 300 nm to 420 nm, and has an emission peak wavelength in a wavelength range from 450 nm to 485 nm.

2. A method for producing the phosphor as set forth in claim 1 , comprising: a mixing process for mixing chemical compounds listed in (1) to (4) below; a baking process for baking the mixture having undergone the mixing process; an annealing process after the baking process; and an acid treatment process after the annealing process:

(1) One or more substances selected from carbonate, oxide, nitride, carbide, hydride, and silicide of elements represented by Me (Me contains one or more elements selected from Sr and Ba);

(2) One or more substances selected from carbonate, oxide, halide, nitride, carbide, hydride, and silicide of elements represented by Re (Re contains Eu);

(3) One or more types of aluminum compounds selected from aluminum oxide, aluminum halide, aluminum nitride, and aluminum metal; and

(4) One or more types of silicon compounds selected from silicon nitride, silicon oxide, silicon oxynitride, and silicon metal.

3. The method for producing the phosphor as set forth in claim 2 , wherein the baking process is performed in an atmospheric gas under one or more atmospheric pressure and at temperatures falling within a range from 1400° C. to 1800° C.

4. The method for producing the phosphor as set forth in claim 2 , wherein the annealing process is performed at temperatures falling within a range from 1200° C. to 1600° C.

5. The method for producing the phosphor as set forth in claim 2 , comprising:

a mixing process for mixing chemical compounds listed in (1) to (4) below and the phosphor obtained in claim 4 ;

a baking process for baking the mixture having undergone the mixing process;

an annealing process after the baking process; and

an acid treatment process after the annealing process:

(1) One or more substances selected from carbonate, oxide, nitride, carbide, hydride, and silicide of elements represented by Me (Me contains one or more elements selected from Sr and Ba);

(2) One or more substances selected from carbonate, oxide, halide, nitride, carbide, hydride, and silicide of elements represented by Re (Re contains Eu);

(3) One or more types of aluminum compounds selected from aluminum oxide, aluminum halide, aluminum nitride, and aluminum metal; and

(4) One or more types of silicon compounds selected from silicon nitride, silicon oxide, silicon oxynitride, and silicon metal.

6. A luminescent device, comprising: a light-emitting device; and the phosphor as set forth in claim 1 .

7. A luminescent device, comprising: a light-emitting device, the phosphor as set forth in claim 1 ; and one or more types of phosphors having emission peak wavelengths longer than that of the phosphor as set forth in claim 1 .

8. The luminescent device as set forth in claim 6 , wherein the light-emitting device is either inorganic or organic light-emitting device emitting light having wavelengths falling within a range from 340 nm to 450 nm.

9. The luminescent device as set forth in claim 6 , wherein the light-emitting device is an LED.

10. The luminescent device as set forth in claim 6 , wherein the luminescent device is a backlight for liquid crystal TVs, light source device for projectors, lighting unit, or signaling device.

11. The method for producing the phosphor as set forth in claim 3 , wherein the annealing process is performed at temperatures falling within a range from 1200° C. to 1600° C.

12. The method for producing the phosphor as set forth in claim 2 , wherein the annealing process is performed in an atmosphere of nitrogen, argon, or hydrogen, or in a mixed atmosphere of two or more of those.

13. The method for producing the phosphor as set forth in claim 2 , wherein an acidic solution is used for the acid treatment process; a hydrochloric acid solution, sulfuric acid solution, or acetic acid solution, a mixed solution of two or more or those, or a solution obtained by diluting the mixed solution with ion-exchange water.

14. The method for producing the phosphor as set forth in claim 5 , wherein the annealing process is performed in an atmosphere of nitrogen, argon, or hydrogen, or in a mixed atmosphere of two or more of those.

15. The method for producing the phosphor as set forth in claim 5 , wherein an acidic solution is used for the acid treatment process; a hydrochloric acid solution, sulfuric acid solution, or acetic acid solution, a mixed solution of two or more or those, or a solution obtained by diluting the mixed solution with ion-exchange water.

16. The method for producing the phosphor as set forth in claim 5 , wherein the phosphor obtained in claim 4 is mixed into the chemical compounds listed in (1) to (4) at a ratio of up to 20% by weight.

Assignments (2)
CHANGE OF NAME Recorded Jun 10, 2016
From: DENKI KAGAKU KOGYO KABUSHIKI KAISHA
To: DENKA COMPANY LIMITED
Reel/Frame 038950/0457 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 5, 2013
From: TAKEDA, GO; YOSHIMATSU, RYO; HIROSAKI, NAOTO
To: DENKI KAGAKU KOGYO KABUSHIKI KAISHA; NATIONAL INSTITUTE FOR MATERIALS SCIENCE
Reel/Frame 030553/0558 →
Priority Claims (1)
JP 2012-274112 · Dec 14, 2012 · national
Continuity (1)
Related Publication 20140167084A1 · Jun 19, 2014