Patent US3438884A successfully refreshed from Google Patents.
US3438884A
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Preparation of boron filaments in an electrical discharge
Assignee: MSA Safety Inc
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Filing: 1966-10-17
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Granted: 1969-04-15
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Expires: 1986-10-17
Abstract
No abstract record available.
Inventors
- 👤 Arvo J Juhola
- 👤 Thomas A Pferdehirt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:56
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/28; B; B01; B01J; B01J19/00; B01J19/08; B01J19/087; B01J19/088; C01; C01B; C01B35/00; C01B35/02; C01B35/023; C23C16/44; C23C16/50; C23C16/503; Y; Y10; Y10S; Y10S148/00; Y10S148/045; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A METHOD OF PREPARING A BORON FILAMENT COMPRISING THE STEPS OF SUBJECTING A GAS CONSISTING ESSENTIALLY OF A MIXTURE OF HYDROGEN AND BORON TRICHLORIDE AND FROM 0 TO ABOUT 5 MOL PERCENT DIBORANE, SAID GAS MIXTURES CONTAINING NOT LESS THAN ABOUT 50 MOL PERCENT HYDROGEN, TO A DIRECT CURRENT THERMIONIC ARC ELECTRICAL DISCHARGE BETWEEN SPACED POSITIVE AND NEGATIVE ELECTRODES WHEREBY A FILAMENT FORMS ON SAID POSITIVE ELECTRODE, AND MOVING SAID POSITIVE ELECTRODE AWAY FROM SAID NEGATIVE ELECTRODE AT A RATE SUCH THAT THE SPACE BETWEEN SAID ELECTRODES IS SUBSTANTIALLY CONSTANT.
Claim 2
Independent Claim
90 words
A METHOD OF PREPARING A BORON FILAMENT COMPRISING THE STEPS OF SUBJECTING A GAS CONSISTING ESSENTIALLY OF A MIXTURE OF HYDROGEN AND BORON TRICHLORIDE AND FROM 0 TO ABOUT 5 MOL PERCENT DIBORANE, SAID GAS MIXTURES CONTAINING NOT LESS THAN ABOUT 50 MOL PERCENT HYDROGEN, TO A DIRECT CURRENT THERMIONIC ARC ELECTRICAL DISCHARGE BETWEEN SPACED POSITIVE AND NEGATIVE ELECTRODES WHEREBY A FILAMENT FORMS ON SAID POSITIVE ELECTRODE, AND MOVING SAID POSITIVE ELECTRODE AWAY FROM SAID NEGATIVE ELECTRODE AT A RATE SUCH THAT THE SPACE BETWEEN SAID ELECTRODES IS SUBSTANTIALLY CONSTANT.
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) | 1972-04-14 | 1972-10-14 | 1973-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-14 | 1976-10-14 | 1977-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-14 | 1980-10-14 | 1981-04-15 | $7700.00 | Window Closed / Lapsed |