Stable 3,3'-dichlorobenzidine dihydrochloride suspension

US5417881A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Dieter Steidl
• Peter Dopfer · Geltendorf, DE
• Wolfgang Ebertz · Hattersheim, DE
• Ernst Schutt · Mörfelden, DE

Key dates

• Filing date: Nov 10, 1993
• Grant date: May 23, 1995
• Expiry date: Nov 10, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C209/90
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

By means of a 3,3'-dichlorobenzidine dihydrochloride suspension in hydrochloric acid, comprising the components PA0 a) 35 to 63.5% by weight of 3,3'-dichlorobenzidine dihydrochloride; PA0 b) 11 to 24% by weight of hydrogen chloride; PA0 c) and 25 to 55% by weight of-water, in each case relative to the total weight of the suspension (100% by weight) and with the proviso that the components a), b) and c) together make 100% by weight; PA0 and whose viscosity is in the range from 80 to 1400 mPa.s, PA0 3,3'-dichlorobenzidine dihydrochloride can be stably suspended in hydrochloric acid at high concentration and consequently low water content and at the same time a suspension having low viscosity can be obtained, so that the slurry flows out of containers without problems even after relatively long static storage.