Information
-
Patent Application
-
20070167646
-
Publication Number
20070167646
-
Date Filed
January 10, 200717 years ago
-
Date Published
July 19, 200717 years ago
-
CPC
-
US Classifications
-
International Classifications
Abstract
The invention relates to an improved process for the production of isocyanates by the reaction of an amine or a mixture of two or more amines with phosgene, the improvement involving the phosgene containing less than about 100 ppm of sulfur in elemental or bound form. The inventive process yields light-colored isocyanates that are suitable for the production of polyurethanes or their precursors (e.g. prepolymers) without the treatment processes heretofore required.
Claims
- 1. In an improved process for the production of isocyanates by the reaction of an amine or a mixture of two or more amines with phosgene, the improvement comprising including phosgene containing less than about 100 ppm of sulfur in elemental or bound form.
- 2. The process according to claim 1, wherein the phosgene contains less than about 60 ppm of sulfur in elemental or bound form.
- 3. The process according to claim 1, wherein the phosgene contains less than about 20 ppm of sulfur in elemental or bound form.
- 4. The process according to claim 1, wherein the reaction is carried out in a solvent.
- 5. The process according to claim 1, wherein the amine is a di- and polyamines of the diphenylmethane series.
- 6. The process according to claim 1, wherein the amine is toluene diaamine.
- 7. The process according to claim 1, wherein the amine is hexamethylenediamine or isophoronediamine or diaminodicyclohexylmethane.
Priority Claims (1)
Number |
Date |
Country |
Kind |
102006002157.6 |
Jan 2006 |
DE |
national |