Detection of marked mineral oils and novel azo dyes

US5487770A · kind A · utility

Assignee

• BASF SE

Inventors

• Rainer Dyllick-Brenzinger · Speyer, DE
• Friedrich-Wilhelm Raulfs · Ludwigshafen, DE
• Ulrike Schlosser · Ludwigshafen, DE
• Karin H. Beck · Ludwigshafen, DE
• Gerhard Scholz · Ludwigshafen, DE

Key dates

• Filing date: Oct 12, 1994
• Grant date: Jan 30, 1996
• Expiry date: Oct 12, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N33/2882
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Method for detecting marked mineral oils by treating the marked mineral oil with an extractant comprising water, a solvent and a base comprises using as marker an azo dye of the formula ##STR1## where ring A may be benzofused, PA1 m is from 1 to 4, PA1 X.sup.1 is hydrogen, C.sub.1 -C.sub.4 -alkyl, cyano or nitro, PA1 X.sup.2 is hydrogen, C.sub.1 -C.sub.4 -alkyl, cyano, nitro, C.sub.1 -C.sub.4 -alkoxy or C.sub.1 -C.sub.16 -alkoxycarbonyl, PA1 X.sup.3 is hydrogen, C.sub.1 -C.sub.4 -alkyl, cyano or C.sub.1 -C.sub.16 -alkoxycarbonyl, and PA1 X.sup.4 is hydrogen, hydroxyl, substituted or unsubstituted C.sub.1 -C.sub.8 -alkyl, C.sub.1 -C.sub.4 -alkoxy, amino, C.sub.1 -C.sub.4 -dialkylamino or substituted or unsubstituted C.sub.1 -C.sub.16 -monoalkylamino, as solvent a partially or completely water-miscible organic solvent, and as base an alkali or alkaline earth metal hydroxide, an alkali metal carbonate or a quaternary ammonium hydroxide, the use of azo dyes as markers for mineral oils, and novel azo dyes.