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US4053513A
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Barium nitride catalysts for the preparation of diamino-diphenylmethanes
Assignee: Huntsman Corp
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Filing: 1977-01-19
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Granted: 1977-10-11
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Expires: 1997-01-19
Abstract
Abstract Covers a method of preparing diaminodiphenylmethanes and higher homologues thereof which comprises the step of condensing aniline and formaldehyde in the presence of a barium nitride catalyst. In another embodiment the barium nitride catalyst is used in conjunction with a silicon nitride catalyst.
Inventors
- 👤 Edward T. Marquis
- 👤 Lewis W. Watts, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:10
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
26 words
A method of preparing diaminodiphenylmethane and higher homologues thereof which comprises the step of condensing aniline and formaldehyde in the presence of a barium nitride catalyst.
Claim 2
Independent Claim
26 words
A method of preparing diaminodiphenylmethane and higher homologues thereof which comprises the step of condensing aniline and formaldehyde in the presence of a barium nitride catalyst.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein said catalyst is present in an amount ranging from about 0.5 to about 3.0 percent by weight based on the weight of aniline present.
Claim 4
Dependent Claim
18 words
The method of claim 2 wherein said catalyst is present in an amount of 1-2 percent by weight.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein silicon nitride is employed as a co-catalyst.
References Cited (Backward Citations)
US3676497A
Cited
US3965182A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |