IP Library Granted Patent US 7,414,272
Granted Patent B2
US 7,414,272 · App. 11/179,575 · Granted Aug 19, 2008

Fluorescent substance containing nitrogen, method for manufacturing the same, and light-emitting device

Assignees: Kabushiki Kaisha Toshiba; Toshiba Materials Co., Ltd.; Toshiba Lighting & Technology Corporation
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Quick Facts
Patent No.
US 7,414,272
App. No.
11/179,575
Granted
Aug 19, 2008
Kind
B2
Abstract

Disclosed is a method for manufacturing a nitrogen-containing fluorescent substance comprising accommodating an oxide fluorescent substance containing two or more elements in a receptacle made of a material containing carbon, and sintering the oxide fluorescent substance in a mixed gas atmosphere containing nitrogen gas.

Claims (29)

1. A method for manufacturing a nitrogen-containing fluorescent substance comprising:

accommodating an oxide fluorescent substance comprising two or more metal elements in a receptacle made of a material comprising carbon; and

sintering the oxide fluorescent substance accommodated in the receptacle made of a material comprising carbon in a mixed gas atmosphere comprising nitrogen gas to produce a nitrogen-containing fluorescent substance.

2. The method according to claim 1 , wherein the receptacle comprises silicon carbide.

3. The method according to claim 1 , wherein the mixed gas atmosphere is a reducing mixed gas atmosphere.

4. The method according to claim 1 , wherein the mixed gas atmosphere further comprises hydrogen gas.

5. The method according to claim 4 , wherein the mixing ratio of the hydrogen gas to the nitrogen gas (H 2 :N 2 ) is 10:90-70:30.

6. The method according to claim 1 , wherein the oxide fluorescent substance has a composition represented by the following general formula (1):

M 2 SiO 4 :Z  (1)

(wherein M is at least one selected from the group consisting of Sr, Ba and Ca; and Z is at least one activator selected from the group consisting of Eu and Ce).

7. The method according to claim 1 , wherein the nitrogen-containing fluorescent substance has a composition represented by the following general formula (2):

M 2 Si 5 N 8 :Z  (2)

(wherein M is at least one selected from the group consisting of Sr, Ba and Ca; and Z is at least one activator selected from the group consisting of Eu and Ce).

8. The method according to claim 1 , wherein the sintering is performed for 2 to 10 hours at a temperature of 1600° C. or more.

9. The method according to claim 1 , wherein the sintering is performed at first for 1 to 3 hours at a temperature ranging from 800° C. to 1400° C. and then for 1 to 9 hours at a temperature of 1600° C. or more.

10. The method according to claim 1 , wherein the receptacle material comprises silicon carbide and carbon.

11. The method according to claim 1 , wherein the receptacle material consists of silicon carbide.

12. The method according to claim 1 , wherein the receptacle material consists of carbon.

13. A method for manufacturing a nitrogen-containing fluorescent substance comprising:

sintering an oxide fluorescent substance represented by the following general formula (1) in a mixed gas atmosphere containing nitrogen gas, thereby converting at least part of the oxide fluorescent substance into a nitrogen-containing fluorescent substance represented by the following general formula (2):

M 2 SiO 4 :Z  (1)

M 2 Si 5 N 8 :Z  (2)

(wherein M is at least one selected from the group consisting of Sr, Ba and Ca; and Z is at least one activator selected from the group consisting of Eu and Ce).

14. The method according to claim 13 , further comprising accommodating the oxide fluorescent substance in a receptacle made of a material containing carbon before sintering the oxide fluorescent substance.

15. The method according to claim 14 , wherein the receptacle comprises silicon carbide or carbon.

16. The method according to claim 13 , wherein the mixed gas atmosphere is a reducing mixed gas atmosphere.

17. The method according to claim 13 , wherein the mixed gas atmosphere is an atmosphere containing hydrogen gas.

18. The method according to claim 17 , wherein the mixing ratio of the hydrogen gas to the nitrogen gas (H 2 :N 2 ) is 10:90-70:30.

19. The method according to claim 13 , wherein the sintering is performed for 2 to 10 hours at a temperature of 1600° C. or more.

Assignments (4)
NUNC PRO TUNC ASSIGNMENT Recorded Feb 19, 2026
From: KABUSHIKI KAISHA TOSHIBA; TOSHIBA LIGHTING & TECHNOLOGY CORPORATION
To: TOSHIBA MATERIALS CO. LTD.
Reel/Frame 073843/0791 →
CHANGE OF NAME Recorded Feb 19, 2026
From: TOSHIBA MATERIALS CO. LTD.
To: NITERRA MATERIALS CO., LTD.
Reel/Frame 074941/0803 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 21, 2008
From: KABUSHIKI KAISHA TOSHIBA (80%)
To: TOSHIBA MATERIALS CO., LTD. (10%); TOSHIBA LIGHTING & TECHNOLOGY CORPORATION (10%)
Reel/Frame 020541/0081 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 31, 2005
From: HIRAMATSU, RYOSUKE; OOTSUKA, KAZUAKI; SHIDA, NAOMI; TAMATANI, MASAAKI; UETAKE, HISAYO; TSUTSUI, YOSHIHITO
To: KABUSHIKI KAISHA TOSHIBA
Reel/Frame 016944/0483 →
Priority Claims (1)
JP 2004-207723 · Jul 14, 2004 · national
Continuity (1)
Related Publication 20060011936A1 · Jan 19, 2006