Patent · US Expired

Method for marking hydrocarbons with anthraquinones

US6811575B2 · kind B2 · utility

9Cited by
16References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 3, 2002
Grant dateNov 2, 2004
Priority date
Expiry dateApr 21, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/13
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Method for invisibly marking a liquid petroleum hydrocarbon. The method comprises adding to the liquid petroleum hydrocarbon at least one dye selected from the group consisting of 1,4,5,8-tetrasubstituted anthraquinones and anthraquinone dimers. The absorption maximum of the dye(s) is in the range from 710 nm to 850 nm.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.