Patent US2765342A successfully refreshed from Google Patents.
US2765342A
Expired / Lapsed
US
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Manufacture of aromatic parahydroxyamines
Assignee: EIDP Inc
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Filing: 1952-10-22
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Granted: 1956-10-02
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Expires: 1972-10-22
Abstract
No abstract record available.
Inventors
- 👤 Spiegler Louis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:10
CPC Classifications
C; C07; C07C; C07C215/00; C07C215/74; C07C215/76
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
156 words
A PROCESS OF PREPARING AN AROMATIC PARAHYDROXYAMINE BY THE REDUCTION OF A NITRO COMPOUND WHICH IS A MONONITRO DERIVATIVE OF AN AROMATIC COMPOUND OF THE CLASS CONSISTING OF HYDROCARBONS FREE FROM NON-AROMATIC HYDROCARBON SUBSTITUENTS OTHER THAN LOWER ALKYL RADICALS AND CONTAINING NO MORE THAN TWO BENZENE RINGS AND MONOCHLORO AND DICHLORO DERIVATIVES THEREOF, SAID NITRO COMPOUND HAVING ITS NITRO GROUP ATTACHED TO AN AROMATIC NUCLEUS WHICH UNSUBSTITUTED IN THE POSITION PARA TO THE NITRO GROUP, WHICH COMPRISES ADDING THE SAID NITRO COMPOUND AND HYDROGEN TO A SUSPENSION OF AN ACID-INSENSITIVE HYDROGENATION CATALYST IN AN AQUEOUS SOLUTION CONTAINING FROM 1 TO 25% BY WEIGHT OF SULFURIC ACID, AT A TEMPERATURE OF FROM 50 TO 145* C., THE PARTIAL PRESSURE OF HYDROGEN BEING MAINTAINED BELOW 760 MM. OF MERCURY AND THE RATE OF ADDITION OF THE NITRO COMPOUND BEING SUCH THAT AT NO TIME DOES THE AMOUNT OF UNREACTED NITRO COMPOUND IN THE SUSPENSION EXCEED ITS SOLUBILITY THEREIN.
Claim 2
Dependent Claim
156 words
A PROCESS OF PREPARING AN AROMATIC PARAHYDROXYAMINE BY THE REDUCTION OF A NITRO COMPOUND WHICH IS A MONONITRO DERIVATIVE OF AN AROMATIC COMPOUND OF THE CLASS CONSISTING OF HYDROCARBONS FREE FROM NON-AROMATIC HYDROCARBON SUBSTITUENTS OTHER THAN LOWER ALKYL RADICALS AND CONTAINING NO MORE THAN TWO BENZENE RINGS AND MONOCHLORO AND DICHLORO DERIVATIVES THEREOF, SAID NITRO COMPOUND HAVING ITS NITRO GROUP ATTACHED TO AN AROMATIC NUCLEUS WHICH UNSUBSTITUTED IN THE POSITION PARA TO THE NITRO GROUP, WHICH COMPRISES ADDING THE SAID NITRO COMPOUND AND HYDROGEN TO A SUSPENSION OF AN ACID-INSENSITIVE HYDROGENATION CATALYST IN AN AQUEOUS SOLUTION CONTAINING FROM 1 TO 25% BY WEIGHT OF SULFURIC ACID, AT A TEMPERATURE OF FROM 50 TO 145* C., THE PARTIAL PRESSURE OF HYDROGEN BEING MAINTAINED BELOW 760 MM. OF MERCURY AND THE RATE OF ADDITION OF THE NITRO COMPOUND BEING SUCH THAT AT NO TIME DOES THE AMOUNT OF UNREACTED NITRO COMPOUND IN THE SUSPENSION EXCEED ITS SOLUBILITY THEREIN.
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) | 1959-10-02 | 1960-04-02 | 1960-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-02 | 1964-04-02 | 1964-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-02 | 1968-04-02 | 1968-10-02 | $7700.00 | Window Closed / Lapsed |