Patent US5800177A successfully refreshed from Google Patents.
US4469619A
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Method of manufacturing a green phosphor
Assignee: Sony Corp
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Filing: 1982-09-30
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Granted: 1984-09-04
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Expires: 2002-09-30
Abstract
Abstract A method for manufacturing a luminescent material having the formula: Y.sub.3 Al.sub.5 O.sub.12 : Tb in which the raw materials for the synthesis are combined in appropriate amounts together with a flux consisting of barium fluoride, barium chloride, or mixtures of the two and then heated in a sealed state to a temperature between about 1300° C. and 1600° C. The resultant product is then leached with an alkaline or acid solution to remove the residual flux from the product.
Inventors
- 👤 Katsutoshi Ohno
- 👤 Tomohiko Abe
- 👤 Teruhiko Hoshina, deceased
- 👤 heir by Ikuko Hoshina
- 👤 heir by Aya Hoshina
- 👤 heir by Ken-Nosuke Hoshina
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:06
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7766; C09K11/7774
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
178 words
A method for the manufacture of a luminescent material having the formula: Y.sub.3 Al.sub.5 O.sub.12 :Tb which comprises the steps of: preparing a mixture of Y 2 O 3 , Al 2 O 3 and Tb 4 O 7 in amounts suitable for synthesis of Y 3 Al 5 O 12 :Tb together with up to 30 mol % of a flux of BaF 2 , BaCl 2 , or mixtures thereof, heating the resulting mixture in a sealed vessel to a temperature between about 1300° C. and about 1600° C., to produce a product consisting predominantly of Y 3 Al 5 O 12 :Tb, and leaching the resulting product with a leaching solution so as to remove the residual flux from said product wherein said flux is present in an amount sufficient to effect a luminescent material exhibiting a higher brightness than the material prepared as above absent the flux, and wherein said luminescent material exhibits a higher brightness than the luminescent material prepared as above but where the heating is conducted in an unsealed covered vessel.
Claim 2
Independent Claim
178 words
A method for the manufacture of a luminescent material having the formula: Y.sub.3 Al.sub.5 O.sub.12 :Tb which comprises the steps of: preparing a mixture of Y 2 O 3 , Al 2 O 3 and Tb 4 O 7 in amounts suitable for synthesis of Y 3 Al 5 O 12 :Tb together with up to 30 mol % of a flux of BaF 2 , BaCl 2 , or mixtures thereof, heating the resulting mixture in a sealed vessel to a temperature between about 1300° C. and about 1600° C., to produce a product consisting predominantly of Y 3 Al 5 O 12 :Tb, and leaching the resulting product with a leaching solution so as to remove the residual flux from said product wherein said flux is present in an amount sufficient to effect a luminescent material exhibiting a higher brightness than the material prepared as above absent the flux, and wherein said luminescent material exhibits a higher brightness than the luminescent material prepared as above but where the heating is conducted in an unsealed covered vessel.
Claim 3
Dependent Claim
15 words
A method according to claim 1 in which said leaching solution is HNO 3 .
Claim 4
Dependent Claim
13 words
A method according to claim 1 in which said leaching solution is HCl.
Claim 5
Dependent Claim
13 words
A method according to claim 1 in which said leaching solution is NaOH.
Claim 6
Dependent Claim
27 words
A method according to claim 1 in which said mixture is sealed in a crucible so that leakage of said flux from said crucible is substantially suppressed.
Claim 7
Dependent Claim
21 words
A method according to claim 2 in which the concentration of HNO 3 is in the range from 0.2N to 5.0N.
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) | 1987-09-04 | 1988-03-05 | 1988-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-04 | 1992-03-05 | 1992-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-04 | 1996-03-05 | 1996-09-04 | $7700.00 | Window Closed / Lapsed |