US4230598A
Expired / Lapsed
US
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Phosphor and process for preparing same
Assignee: Bpifrance Financement SA
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Filing: 1978-08-25
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Granted: 1980-10-28
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Expires: 1998-08-25
Abstract
Abstract A phosphor of the fluoride type mixed with potassium and yttrium doped with divalent europium, characterized in that it responds to the formula K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x wherein x is less than 0.06. The invention also concerns a process for preparing this product which may be used in a laser.
Inventors
- 👤 Alain Vedrine
- 👤 Jean-Claude Gacon
- 👤 Georges Boulon
- 👤 Danielle Trottier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:36
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7783; C09K11/779; C09K11/7791
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
47 words
A divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula: K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x wherein x is positive and up to 0.06, the said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400° K.
Claim 2
Dependent Claim
47 words
A divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula: K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x wherein x is positive and up to 0.06, the said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400° K.
Claim 3
Dependent Claim
15 words
The phosphor of claim 1 wherein x is in the range between 0.01 and 0.03.
Claim 4
Dependent Claim
9 words
A laser source comprising the phosphor of claim 1.
Claim 5
Dependent Claim
8 words
A lamp including the phosphor of claim 1.
Claim 6
Dependent Claim
124 words
A process for preparing a divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula K.sub.(1-x) Eu x Y 3 F 10+x , wherein x is positive and up to 0.06, said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400° K., comprising: mixing in potassium fluoride, yttrium trifluoride and a divalent europium based doping agent in amounts corresponding to said formula, the said doping agent being selected from the group consisting of europium difluoride and a mixture of metallic europium and europium trifluoride in stoichiometric proportions; heating said resultant mixture at 900° C. for 15 hours under reduction conditions; and then permitting the mixture to slowly cool thus obtaining the phosphor.
Claim 7
Dependent Claim
124 words
A process for preparing a divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula K.sub.(1-x) Eu x Y 3 F 10+x , wherein x is positive and up to 0.06, said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400° K., comprising: mixing in potassium fluoride, yttrium trifluoride and a divalent europium based doping agent in amounts corresponding to said formula, the said doping agent being selected from the group consisting of europium difluoride and a mixture of metallic europium and europium trifluoride in stoichiometric proportions; heating said resultant mixture at 900° C. for 15 hours under reduction conditions; and then permitting the mixture to slowly cool thus obtaining the phosphor.
Claim 8
Dependent Claim
19 words
The process of claim 5, wherein the initial mixture is finely ground and placed in a sealed nickel ampoule.
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) | 1983-10-28 | 1984-04-28 | 1984-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-28 | 1988-04-28 | 1988-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-28 | 1992-04-28 | 1992-10-28 | $7700.00 | Window Closed / Lapsed |