Process for the crystalline precipitation of chromogens

US4295857A · kind A · utility

Inventors

• Peter Schuler · Karlsruhe, DE
• Erwin Braun · Ingolstadt, DE

Key dates

• Filing date: Apr 3, 1980
• Grant date: Oct 20, 1981
• Expiry date: Apr 3, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N33/52
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention contemplates a process for the crystalline precipitation of a chromogen from solution thereof in a solvent and within a capillary. The process involves first initiating a course of crystalline precipitation of the chromogen by initially and locally supersaturating the solution within the capillary, and thereafter evaporating the solvent at a rate and in an environment sufficient for further crystallization to proceed unimpeded by local supersaturation.