US3881941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alkali metal polytungstate phosphors containing europium
Assignee: General Electric Co
•
Filing: 1973-10-01
•
Granted: 1975-05-06
•
Expires: 1993-10-01
Abstract
Abstract A particular class of alkaline metal polytungstate materials containing europium have been found to be superior in their emission response of converting UV radiation to visible light when compared with conventional phosphors. These phosphors are crystalline solids wherein the europium ion is contained in a particular polytungstate structure and exhibit phosphorescence when excited by a source of 2537A. radiation which makes them especially useful in photodetection systems.
Inventors
- 👤 John A Kernohan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:27
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7728; C09K11/7736; C09D; C09D11/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
37 words
USE OF AN ALKALI METAL POLYTUNGSTATE PHOSPHOR AS A PHOTODETECTION MEANS COMPRISING WATER-SOLUBLE CRYSTALS ESSENTIALLY ACCORDING TO THE GENERAL FORMULA: M7EUW10O35XH2O WHEREIN M OS AN ALKALI METAL ION X IS AN INTEGER FROM 0 TO ABOUT 24
Claim 2
Dependent Claim
37 words
USE OF AN ALKALI METAL POLYTUNGSTATE PHOSPHOR AS A PHOTODETECTION MEANS COMPRISING WATER-SOLUBLE CRYSTALS ESSENTIALLY ACCORDING TO THE GENERAL FORMULA: M7EUW10O35XH2O WHEREIN M OS AN ALKALI METAL ION X IS AN INTEGER FROM 0 TO ABOUT 24
Claim 3
Dependent Claim
14 words
In the use as in claim 1 wherein the alkali metal ion is sodium.
Claim 4
Dependent Claim
14 words
In the use as in claim 1 wherein the alkali metal ion is potassium.
Claim 5
Dependent Claim
14 words
In the use as in claim 1 wherein X is an integer greater than
Claim 6
Dependent Claim
15 words
A PHOSPHORESCENT MARKING INK WHICH COMPRISES A LIQUID DISPERSION OF THE PHOSPHOR IN CLAIM 1.
Claim 7
Dependent Claim
13 words
A marking ink as in claim 5 containing approximately 1-5 weight percent phosphor.
Claim 8
Dependent Claim
13 words
A marking ink as in claim 5 which also contains an adhesive binder.
Claim 9
Dependent Claim
12 words
A marking ink as in claim 7 which also contains a colorant.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |