Boston Advanced Technologies, Inc.

On-site Analysis, Inc.

Sun Chemical Corporation

Mohammad S Farahat

Richard H Clarke

Juanita M Parris

William Edward Asher

Xiaobo Zhu

A liquid can be marked for identification purposes with at least first and second miscible markers. The markers are mixed in the liquid so that the ratio of the concentration of the first marker to the concentration of the second marker is substantially equal to a predetermined value. Thus, by comparing the ratio of the measured concentration of the first marker to the measured concentration of the second marker with predetermined values the liquid can be uniquely identified. The detectors can be connected to a processor and control unit () for initiation of testing, for processing of detection signal from the detectors, and for display of readout information. Processor and control unit () can include a look up table () for storing information about marking patterns, a comparison element () for comparing measured values with values supplied by look up table (), and a display ().

Apparatus for marking and identifying liquids

Methods for marking a liquid and methods and systems for identifying marked liquids. A liquid can be marked for identification purposes with at least a first marker and a second marker. Each of the markers is miscible with the liquid. The markers are mixed in the liquid so that the ratio of the concentration of the first marker to the concentration of the second marker is substantially equal to a predetermined value. Thus, when a system according to the invention measures the concentrations of the first and second markers, the system can compare the ratio of the measured concentration of the first marker to the measured concentration of the second marker with a look up table of the predetermined values to provide information concerning the identity of the liquid. In a preferred embodiment, the concentration of the markers is measured using an absorption spectrometer. When using an absorption spectrometer to measure the concentration of the markers, each of the markers has an absorbance spectrum with at least one wavelength range where the marker's absorbance is differentiable from the absorbance of the background liquid and any other marker in the liquid.

Method for marking and identifying liquids

Growing community of inventors

Westboro, MA, United States of America

Mohammad S Farahat