Patent US3925239A successfully refreshed from Google Patents.
US3925239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing a luminescent alkaline earth halophosphate
Assignee: US Philips Corp
•
Filing: 1972-09-11
•
Granted: 1975-12-09
•
Expires: 1992-09-11
Abstract
Abstract A method of manufacturing a luminescent alkaline earth halophosphate having the apatite crystal structure and being activated by trivalent antimony and optionally also by bivalent manganese in which antimony is contacted as a gaseous antimony trioxide in an inert atmosphere at a temperature of between 900* and 1,250*C with a reaction mixture from which an alkaline earth halophosphate having the apatite structure can be produced or is contacted with a formed non-activated alkaline earth halophosphate having the apatite structure or with an alkaline earth halophosphate comprising manganese only. The gaseous antimony trioxide is formed by heating a mixture which comprises an antimonite of one or more of the alkaline earth metals, of cadmium or of manganese, or of a mixture which comprises an antimonate of one or more of the alkaline earth metals, of cadmium or manganese and a pyrophosphate.
Inventors
- 👤 Willem Lambertus Wanmaker
- 👤 Dragutin Radielovic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:05
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/70; C09K11/72; C09K11/73; C09K11/74; C09K11/75; C09K11/76
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
220 words
IN A METHOD OF PREPARING A TRIVALENT ANTIMONY ACTIVATED LUMINESCENT ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE BY CONTACTING GASEOUS ANTIMONY TRIOXIDE IN AN INERT ATMOSPHERE WITH A BASE MATERIAL AT A TEMPERATURE OF BETWEEN 900* AND 1,250*C, SAID BASE MATERIAL COMPRISING AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF MIXTURES OF REACTANTS CAPABLE OF PRODUCING ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE, NON-ACTIVATED ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE AND MANGANESE ACTIVATED ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE, THE IMPROVEMENT WHICH COMPRISES FORMING THE GASEOUS ANTIMONY TRIOXIDE IN AT LEAST ONE VESSEL SEPARATED FROM THE BASE MATERIAL BY HEATING FOR AT LEAST 0.25 HOUR AT A TEMPERATURE BETWEEN 900* AND 1,250**C AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF THE ALKALINE EARTH ANTIMONITES, CADMIUM ANTIMONITE, MANGANESE ANTIMONITE, MIXTURES OF AT LEAST ONE OF SAID ANTIMONITES WITH AT LEAST ONE OF CALCIUM AND STRONTIUM PYROPHOSPHATE, MIXTURES OF AT LEAST ONE ALKALINE EARTH ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE, MIXTURES OF CADMIUM ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE AND MIXTURES OF MANGANESE ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE, IN A MOLAR RATIO OF ANTIMONATE TO PYROPHOSPHATE OF BETWEEN 4 AND 0.5, AND CONTACTING THE GASEOUS ANTIMONY TRIOXIDE OBTAINED WITH THE BASE MATERIAL BY MEANS OF AN INERT GAS STREAM.
Claim 2
Dependent Claim
220 words
IN A METHOD OF PREPARING A TRIVALENT ANTIMONY ACTIVATED LUMINESCENT ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE BY CONTACTING GASEOUS ANTIMONY TRIOXIDE IN AN INERT ATMOSPHERE WITH A BASE MATERIAL AT A TEMPERATURE OF BETWEEN 900* AND 1,250*C, SAID BASE MATERIAL COMPRISING AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF MIXTURES OF REACTANTS CAPABLE OF PRODUCING ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE, NON-ACTIVATED ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE AND MANGANESE ACTIVATED ALKALINE EARTH HALOPHOSPHATE HAVING THE APATITE STRUCTURE, THE IMPROVEMENT WHICH COMPRISES FORMING THE GASEOUS ANTIMONY TRIOXIDE IN AT LEAST ONE VESSEL SEPARATED FROM THE BASE MATERIAL BY HEATING FOR AT LEAST 0.25 HOUR AT A TEMPERATURE BETWEEN 900* AND 1,250**C AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF THE ALKALINE EARTH ANTIMONITES, CADMIUM ANTIMONITE, MANGANESE ANTIMONITE, MIXTURES OF AT LEAST ONE OF SAID ANTIMONITES WITH AT LEAST ONE OF CALCIUM AND STRONTIUM PYROPHOSPHATE, MIXTURES OF AT LEAST ONE ALKALINE EARTH ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE, MIXTURES OF CADMIUM ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE AND MIXTURES OF MANGANESE ANTIMONATE WITH AT LEAST ONE ALKALINE EARTH PYROPHOSPHATE, IN A MOLAR RATIO OF ANTIMONATE TO PYROPHOSPHATE OF BETWEEN 4 AND 0.5, AND CONTACTING THE GASEOUS ANTIMONY TRIOXIDE OBTAINED WITH THE BASE MATERIAL BY MEANS OF AN INERT GAS STREAM.
Claim 3
Dependent Claim
77 words
The method of claim 1, wherein a first reaction vessel containing the base material is placed in a furnace and one or more further reaction vessels containing the substance from which the gaseous antimony trioxide is formed are placed in the vicinity of the first reaction vessel in the furnace and wherein the furnace is subsequently brought to a temperature of between 900* and 1,250*C for at least 0.25 hour while passing through an inert gas stream.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein the antimonite is selected from the group consisting of calcium antimonite, strontium antimonite and mixtures thereof.
Claim 5
Dependent Claim
26 words
The method of claim 2, wherein heating in the furnace is performed for 0.25 to 1.50 hours at a temperature of between 1, 050* and 1,200*C.
Claim 6
Dependent Claim
25 words
The method of claim 2, wherein after homogenizing the resultant product is heated to a temperature of between 700* and 1,200*C in an inert 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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |