Patent US2823231A successfully refreshed from Google Patents.
US2823231A
Expired / Lapsed
US
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Process for the production of naphthalene-2, 6-dicarboxylic acid and its derivatives
Assignee: Henkel AG and Co KGaA
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Filing: 1956-01-10
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Granted: 1958-02-11
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Expires: 1976-01-10
Abstract
No abstract record available.
Inventors
- 👤 Raecke Bernhard
- 👤 Schirp Hubert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:19
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/41; C07C51/412
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
THE METHOD OF PRODUCING NAPHTHALENE-2,6-DICARBOXYLIC ACID FROM A NAPHTHALENE-MONOCARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF A-NAPHTHOIC ACID AND B-NAPHTHOIC ACID, WHICH COMPRISES CONVERTING SAID NAPHTHALENE-MONOCARBOXYLIC ACID INTO A CORRESPONDING MONO-ALKALI METAL SALT, HEATING SAID MONO-SALT TO A TEMPERATURE ABOVE ABOUT 360*C. AND BELOW THE TEMPERATURE AT WHICH SUBSTANTIAL DECOMPOSITION OF THE STARTING MATERIAL AND REACTION PRODUCTS TAKES PLACE, IN AN INERT ATMOSPHERE OF AN INERT GAS SELECTED FROM THE GROUP CONSISTING OF CARBON DIOXIDE AND NITROGEN, AND CONVERTING THE DIALKALI METAL SALT OF NAPHTHALENE-2,6-DICARBOXYLIC ACID FORMED THEREBY INTO FREE NAPHTHALENE-2,6-DICARBOXYLIC ACID BY ACIDIFICATION OF SAID DI-ALKALI METAL SALT WITH A STRONG MINERAL ACID.
Claim 2
Independent Claim
104 words
THE METHOD OF PRODUCING NAPHTHALENE-2,6-DICARBOXYLIC ACID FROM A NAPHTHALENE-MONOCARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF A-NAPHTHOIC ACID AND B-NAPHTHOIC ACID, WHICH COMPRISES CONVERTING SAID NAPHTHALENE-MONOCARBOXYLIC ACID INTO A CORRESPONDING MONO-ALKALI METAL SALT, HEATING SAID MONO-SALT TO A TEMPERATURE ABOVE ABOUT 360*C. AND BELOW THE TEMPERATURE AT WHICH SUBSTANTIAL DECOMPOSITION OF THE STARTING MATERIAL AND REACTION PRODUCTS TAKES PLACE, IN AN INERT ATMOSPHERE OF AN INERT GAS SELECTED FROM THE GROUP CONSISTING OF CARBON DIOXIDE AND NITROGEN, AND CONVERTING THE DIALKALI METAL SALT OF NAPHTHALENE-2,6-DICARBOXYLIC ACID FORMED THEREBY INTO FREE NAPHTHALENE-2,6-DICARBOXYLIC ACID BY ACIDIFICATION OF SAID DI-ALKALI METAL SALT WITH A STRONG MINERAL ACID.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-10 | 1961-08-12 | 1962-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-10 | 1965-08-12 | 1966-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-10 | 1969-08-12 | 1970-02-11 | $7700.00 | Window Closed / Lapsed |