Patent US2857249A successfully refreshed from Google Patents.
US2857249A
Expired / Lapsed
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Method of purifying silicon tetrachloride
Assignee: Individual
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Filing: 1956-07-03
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Granted: 1958-10-21
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Expires: 1976-07-03
Abstract
No abstract record available.
Inventors
- 👤 Guenter A Wolff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:25
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
70 words
A METHOD OF PURIFYING SILICON TETRACHLORIDE OF TRACES OF BORON TRICHLORIDE COMPRISING ADDING A NUCLEOPHILIC AMINE OF THE STRUCTURAL FORMULA NR3 WHERE R IS AN ALKYL RADICAL TO THE SILICON TETRACHLORIDE CONTAMINATED BY SAID BORON TRICHLORIDE SO AS TO FORM AN ADDITION-COMPLEX COMPOUND OF BORON OF LOW VAPOR PRESSURE AND SEPARATING THE LIQUID BY A FRACTIONAL DISTALLATION UNDER REFLUX CONDITIONS INTO A BORON-FREE SILICON TETRACHLORIDE FRACTION AND A BORONCONTAMINATED RESIUDE.
Claim 2
Independent Claim
70 words
A METHOD OF PURIFYING SILICON TETRACHLORIDE OF TRACES OF BORON TRICHLORIDE COMPRISING ADDING A NUCLEOPHILIC AMINE OF THE STRUCTURAL FORMULA NR3 WHERE R IS AN ALKYL RADICAL TO THE SILICON TETRACHLORIDE CONTAMINATED BY SAID BORON TRICHLORIDE SO AS TO FORM AN ADDITION-COMPLEX COMPOUND OF BORON OF LOW VAPOR PRESSURE AND SEPARATING THE LIQUID BY A FRACTIONAL DISTALLATION UNDER REFLUX CONDITIONS INTO A BORON-FREE SILICON TETRACHLORIDE FRACTION AND A BORONCONTAMINATED RESIUDE.
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) | 1961-10-20 | 1962-04-21 | 1962-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-20 | 1966-04-21 | 1966-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-20 | 1970-04-21 | 1970-10-21 | $7700.00 | Window Closed / Lapsed |