Organic compounds -- part of the class 532-570 series – Organic compounds – Amino nitrogen containing
Reexamination Certificate
2007-08-07
2007-08-07
Davis, Brian (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Amino nitrogen containing
C564S326000, C560S347000, C560S358000, C560S359000
Reexamination Certificate
active
11170624
ABSTRACT:
The invention provides a process for the preparation of polyamines of the diphenylmethane series. This process comprisesa) reacting aniline and formaldehyde in a molar ratio of 1.5:1 to 6:1, in the presence of an acid catalyst at temperatures of 20° C. to 100° C., in which the water content in the acid reaction mixture is <20 wt. % and a degree of protonation of <15% is established, andb) increasing the temperature of the reaction to a temperature of 110° C. to 250° C. when the ratio of the weight contents of p-aminobenzylaniline to 4,4′-MDA in the reaction mixture falls below a value of 1.00.
REFERENCES:
patent: 3517062 (1970-06-01), Powers
patent: 4259526 (1981-03-01), Dunlap et al.
patent: 6433219 (2002-08-01), Ströfer et al.
patent: 6639102 (2003-10-01), Hagen et al.
patent: 6831192 (2004-12-01), Ströfer et al.
patent: 2004/0002579 (2004-01-01), Hagen et al.
patent: 2005/0014975 (2005-01-01), Stofer et al.
patent: 2005/0222291 (2005-10-01), Pirkl et al.
patent: 2005/0240054 (2005-10-01), Liman et al.
patent: 1 011 337 (1957-06-01), None
patent: 198 04 918 (1999-08-01), None
Adamson Richard
Hagen Torsten
Koch Daniel
Pirkl Hans-Georg
Pohl Fritz
Bayer MaterialScience AG
Brown N. Denise
Davis Brian
Gil Joseph C.
Whalen Lyndanne M.
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