Dipyrromethenes and azadipyrromethenes as markers for petroleum products
US9222043B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2010 |
| Grant date | Dec 29, 2015 |
| Priority date | — |
| Expiry date | Jan 5, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10L1/232
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Marking a petroleum product includes adding a covert dye selected from the group consisting of azadipyrromethene dyes, dipyrromethene dyes, and any combination thereof to the petroleum product and distributing the dye in the petroleum product. A petroleum product selected for analysis may be spectroscopically analyzed for the presence of an azadipyrromethene dye, a dipyrromethene dye, or a combination thereof. A concentration of at least one azadipyrromethene or dipyrromethene dye present in the portion of the petroleum product may be determined to identify the petroleum product as counterfeit, adulterated, or authentic based on the determined concentration of the azadipyrromethene or dipyrromethene dye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.