| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an improved method for marking a liquid petroleum hydrocarbon with a plurality of marker. <P>SOLUTION: The method comprises adding: (i) at least one anthraquinone dye having an absorption maximum in the range from 710-850 nm selected from the group consisting of 1, 4, 5, 8-tetrasubstituted anthraquinones and anthraquinone dimers; and (ii) at least one visible dye having an absorption maximum in the range 500-700 nm, to the liquid petroleum hydrocarbon such as lubricating oil, hydraulic fluid, brake fluid, gasoline, diesel oil, kerosine, jet fuel, or the like. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
