Patent US3880770A successfully refreshed from Google Patents.
US3880770A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making improved magnesium aluminum gallate phosphors
Assignee: GTE Sylvania Inc
•
Filing: 1973-03-22
•
Granted: 1975-04-29
•
Expires: 1993-03-22
Abstract
Abstract Increased luminence intensity in magnesium aluminum gallate phosphors as well as magnesium gallate phosphors is achieved by utilizing a fluorine source in the raw material mix and by conducting initial processing in a humid, oxidizing atmosphere. Additionally, processing time is drastically reduced.
Inventors
- 👤 Charles F Chenot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:50
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/62; C09K11/64
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
179 words
A METHOD OF MANUFACTURING MAGNESIUM ALUMINUM GALLATE LUMINESCENT MATERIAL ACTIVATED BY MANGANESE WHICH COMPRISES THE STEPS OF: FORMING A MXTURE OF RAW MATERIALS WHICH WILL YIELD SAID LUMINESCENT MATERIAL, SAID MATERIALS INCLUDING A SOURCE OF MAGNESIUM SELECTED FROM THE GROUP CONSISTING OF MGO AND MGCO3, A SOURCE OF GALLIUM AS B-GA2O3 AND A SORUCE OF ALUMINUM SELECTED FROM THE GROUP CONSISTING OF, A-AL2O3 AND AL(OH)3; INCLUDING IN SAID RAW MATERIALS A SOURCE OF FLUORINE AS MGF2; THOROUGHLY MIXING SAID RAW MATERIALS AND SAID SOURCE OF FLUORINE; HEAT TREATING SAID RAW MATERIALS IN ALUMINA CRUCIBLES IN A HUMIDIFED, OXIDIZING ATMOSPHERE THE WATER CONTENT OF SAID ATMOSPHERE BEING SUFFICIENT TO EFFECT THE HYDROLYSIS OF MGF2 FOR ABOUT 2HOURS AT A TEMPERATURE OF ABOUT 1200*C-1300*C; COOLING AND COMMINUTING SAID MATERIAL; EHEATING SAID MATERIAL AT LEAST TWICE IN SILICA CRUCIBLES IN A REDUCING ATMOSPHERE FOR LESS THAN 40 MINUTES EACH TIME AT A TEMPERATURE OF ABOUT 1200*C-1300*C; AND COOLING, COMMINUTING AND SIEVING SAID MATERIAL THE SECOND AND SUBSEQUENT REHEATING IN SAID REDUCING ATMOSPHERE EFFECTING AN IMPROVEMENT IN THE LUMINESCENE EFFECIENCY OF SAID MATERIAL.
Claim 2
Independent Claim
179 words
A METHOD OF MANUFACTURING MAGNESIUM ALUMINUM GALLATE LUMINESCENT MATERIAL ACTIVATED BY MANGANESE WHICH COMPRISES THE STEPS OF: FORMING A MXTURE OF RAW MATERIALS WHICH WILL YIELD SAID LUMINESCENT MATERIAL, SAID MATERIALS INCLUDING A SOURCE OF MAGNESIUM SELECTED FROM THE GROUP CONSISTING OF MGO AND MGCO3, A SOURCE OF GALLIUM AS B-GA2O3 AND A SORUCE OF ALUMINUM SELECTED FROM THE GROUP CONSISTING OF, A-AL2O3 AND AL(OH)3; INCLUDING IN SAID RAW MATERIALS A SOURCE OF FLUORINE AS MGF2; THOROUGHLY MIXING SAID RAW MATERIALS AND SAID SOURCE OF FLUORINE; HEAT TREATING SAID RAW MATERIALS IN ALUMINA CRUCIBLES IN A HUMIDIFED, OXIDIZING ATMOSPHERE THE WATER CONTENT OF SAID ATMOSPHERE BEING SUFFICIENT TO EFFECT THE HYDROLYSIS OF MGF2 FOR ABOUT 2HOURS AT A TEMPERATURE OF ABOUT 1200*C-1300*C; COOLING AND COMMINUTING SAID MATERIAL; EHEATING SAID MATERIAL AT LEAST TWICE IN SILICA CRUCIBLES IN A REDUCING ATMOSPHERE FOR LESS THAN 40 MINUTES EACH TIME AT A TEMPERATURE OF ABOUT 1200*C-1300*C; AND COOLING, COMMINUTING AND SIEVING SAID MATERIAL THE SECOND AND SUBSEQUENT REHEATING IN SAID REDUCING ATMOSPHERE EFFECTING AN IMPROVEMENT IN THE LUMINESCENE EFFECIENCY OF SAID MATERIAL.
Claim 3
Dependent Claim
47 words
The method of claim 1 wherein said luminescent material produced has the general formula MgaMnbGa2 c AlcO3 a b wherein 0.85 < or = a*b < or = 1.05 0 < or = c < or = 1.2 0.001 < or = b < or = 0.06.
Claim 4
Dependent Claim
32 words
The method of claim 2 wherein said reducing atmosphere comprises a mixture of H2 and N2 with said H2 being present in an amount of about 0.25 to 1.00 percent by volume.
References Cited (Backward Citations)
US2392814A
Cited
US3407325A
Cited
US3448056A
Cited
US3499843A
Cited
US3502592A
Cited
US3595802A
Cited
US3577350A
Cited
US3649550A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |