US3897359A
Expired / Lapsed
US
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Europium activated alkaline earth metal alumino silicate phosphor and method for preparing the same
Assignee: Panasonic Holdings Corp
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Filing: 1970-06-02
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Granted: 1975-07-29
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Expires: 1990-06-02
Abstract
Abstract A phosphor consisting of a solid solution of a complex oxide of alkaline earth metals, aluminum and silicon, which contains oxides of the alkaline earth metals (Ca, Sr and Ba), aluminum and silicon as a host material, which is activated by divalent europium (Eu2 ), shows a bright luminescence spectrum in a wavelength region from near ultraviolet to bluish white, which depends upon the composition of the host material, through an excitation by ultraviolet rays or electron beams. The phosphor is utilized as a blue component for a fluorescent discharge lamp for copying, a flying spot tube, a storage tube or a Braun tube.
Inventors
- 👤 Yoshickika Kobayashi
- 👤 Mutsuo Masuda
- 👤 Masanori Takagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:07
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7728; C09K11/77344
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
A PHOSPHOR WHICH COMPRISES A SOLID SOLUTION OF A COMPLEX OXIDE OF ALKALINE EARTH METAL, ALUMIUM AND SILICON, WHICH CONTAINS OXIDES OF AT LEAST ONE OF ALKALINE EARTH METALS SELECTED FROM CALCIUM, STRONTIUM AND BARIUM, ALUMINUM AND SILICON, AND EUROPIUM AS A ACTIVATOR, WHOSE CHEMICAL COMPOSITION IS REPRESENTED BY THE FOLLOWING FORMULA: (CAS SRV BAZ EUP) OZ+Y+Z+P A12O3. 2SIO2 WHERE 0.95 X+ Y + Z+P 1.05 0.005 P 0.1
Claim 2
Dependent Claim
69 words
A PHOSPHOR WHICH COMPRISES A SOLID SOLUTION OF A COMPLEX OXIDE OF ALKALINE EARTH METAL, ALUMIUM AND SILICON, WHICH CONTAINS OXIDES OF AT LEAST ONE OF ALKALINE EARTH METALS SELECTED FROM CALCIUM, STRONTIUM AND BARIUM, ALUMINUM AND SILICON, AND EUROPIUM AS A ACTIVATOR, WHOSE CHEMICAL COMPOSITION IS REPRESENTED BY THE FOLLOWING FORMULA: (CAS SRV BAZ EUP) OZ+Y+Z+P A12O3. 2SIO2 WHERE 0.95 X+ Y + Z+P 1.05 0.005 P 0.1
Claim 3
Dependent Claim
95 words
A phosphor which comprises a solid solution of a complex oxide of alkaline earth metal, aluminum and silicon, which contains oxides of at least one of alkaline earth metals selected from calcium, strontium and barium, aluminum and silicon, and europium as an activator, whose chemical composition is represented by the following formula: (Cax Sry Baz Eup) Ox y z p Al2O3 . 2SiO2 where 0.95 < or = x + y + z + p < or = 1.05 0.005 < or = p < or = 0.1 z + p < or = 0.9
Claim 4
Dependent Claim
95 words
A phosphor which comprises a solid solution of a complex oxide of alkaline earth metal, aluminum and silicon, which contains oxides of at least one of alkaline earth metals selected from calcium, strontium and barium, aluminum and silicon, and europium as an activator, whose chemical composition is represented by the following formula: (Cax Sry Baz Eup) Ox y z p Al2O3 . 2SiO2 where 0.95 < or = x + y + z + p < or = 1.05 0.005 < or = p < or = 0.1 z + p < or = 0.9
Claim 5
Dependent Claim
39 words
A phosphor according to claim 1, where the alkaline earth metal is only barium, and x y O, 0.95 < or = z + p < or = 1.05 and 0.005 < or = p < or = 0.1.
Claim 6
Independent Claim
141 words
A method for preparing a phosphor consisting of a solid solution of a complex oxide containing oxides of at least one of alkaline earth metals selected from calcium, strontium and barium, aluminum and silicon, and europium as an activator, whose chemical composition is represented by: (Cax Sry Baz Eup) Ox y z p Al2O3. 2SiO2 where 0.95 < or = x + y + z + p < or = 1.05 0.005 < or = p < or = 0.1 which comprises the first step of preliminarily firing a mixture of at least one member selected from carbonates, oxalates, nitrates and hydroxides containing said respective oxide components to thermally decompose said salt to an oxide mixture, and the second step of firing said oxide mixture at a temperature ranging from 1,100* to 1,350*C to form a solid solution of complex oxide.
Claim 7
Independent Claim
141 words
A method for preparing a phosphor consisting of a solid solution of a complex oxide containing oxides of at least one of alkaline earth metals selected from calcium, strontium and barium, aluminum and silicon, and europium as an activator, whose chemical composition is represented by: (Cax Sry Baz Eup) Ox y z p Al2O3. 2SiO2 where 0.95 < or = x + y + z + p < or = 1.05 0.005 < or = p < or = 0.1 which comprises the first step of preliminarily firing a mixture of at least one member selected from carbonates, oxalates, nitrates and hydroxides containing said respective oxide components to thermally decompose said salt to an oxide mixture, and the second step of firing said oxide mixture at a temperature ranging from 1,100* to 1,350*C to form a solid solution of complex oxide.
Claim 8
Dependent Claim
21 words
A method according to claim 4, where the first step is carried out at a firing temperature of 800* to 1,000*C.
Claim 9
Dependent Claim
18 words
A method according to claim 4, wherein the second step is carried out in a weakly reducible atmosphere.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |