US4083870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for converting polyaminopolyaryl-methanes into diaminodiarylmethanes
Assignee: Bayer AG
•
Filing: 1974-02-12
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Granted: 1978-04-11
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Expires: 1994-02-12
Abstract
Abstract Polyaminopolyarylmethanes and an aromatic monoamine unsubstituted in an ortho or a para position to the amino group are heated in water to produce diaminodiarylmethanes.
Inventors
- 👤 Hans-Josef Buysch
- 👤 Peter Ziemek
- 👤 Roderich Raue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:50
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/68; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/32; C08G18/3225; C08G18/3237; C08G18/3243; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7657; C08G18/7664; C08G18/7671; C08G59/00; C08G59/18; C08G59/40; C08G59/50; C08G59/5033
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
55 words
A process for the production of diaminodiarylmethanes which contain an improved proportion of 2,4'-diaminodiarylmethanes by heating polyaminopolyarylmethanes in the liquid phase with an aromatic monoamine which has at least one free position in the ortho- or para-position to the amino group, characterized in that the reaction is carried out solely in the presence of water.
Claim 2
Dependent Claim
55 words
A process for the production of diaminodiarylmethanes which contain an improved proportion of 2,4'-diaminodiarylmethanes by heating polyaminopolyarylmethanes in the liquid phase with an aromatic monoamine which has at least one free position in the ortho- or para-position to the amino group, characterized in that the reaction is carried out solely in the presence of water.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein the reaction is conducted at a temperature of above 220° C.
Claim 4
Dependent Claim
10 words
The process of claim 1 wherein the monarylamine is aniline.
Claim 5
Dependent Claim
48 words
The process for converting 4,4'-diphenylmethane diamine into 2,4'-diphenylmethane diamine which consists of heating in water the said 4,4'-isomer with an aromatic monoamine which is unsubstituted in at least one position ortho to the amino group or para to the amino group to a temperature of above 220° C.
Claim 6
Dependent Claim
48 words
The process for converting 4,4'-diphenylmethane diamine into 2,4'-diphenylmethane diamine which consists of heating in water the said 4,4'-isomer with an aromatic monoamine which is unsubstituted in at least one position ortho to the amino group or para to the amino group to a temperature of above 220° C.
References Cited (Backward Citations)
DE107718C
Cited
GB1127347A
Cited
GB1169127A
Cited
US3857890A
Cited
DE2135347A1
Cited
DD107718A5
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-10 | 1981-10-10 | 1982-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-10 | 1985-10-10 | 1986-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-10 | 1989-10-10 | 1990-04-11 | $7700.00 | Window Closed / Lapsed |