Abstract: A method of coloring a substrate is disclosed that includes the steps of dissolving a vegetable oil ester based solvent wherein the ester is selected from a group consisting of esters having carbon chain length of C-1 to C-18 in a liquid solvent dye to form a low-sulfur containing dye formulation such that the vegetable oil ester is present in an amount of between about 5 and 80 percent by weight of the dye formulation, and mixing sufficient amounts of the dye formulation with the substrate to produce mixtures of predetermined color in which the levels of toxic substrate are substantially less than in otherwise equivalent mixtures that include hydrocarbon-based solvents.

Abstract: An environment friendly writing instrument that includes a hollow body, an ink reservoir at the first end of the hollow body to hold ink, and a felt tip which extends from the reservoir to the second end of the hollow body, and a dye formulation comprising (I) a vegetable oil ester in an amount of between about 5 and 80 percent by weight of the dye formulation, (ii) a liquid solvent dye present in the dye formulation in an amount sufficient to impart a predetermined color to the dye formulation and (iii) sulfur in an amount of less than about 10 ppm, and wherein the ink is formed from the dye formulation.

Abstract: A method of coloring a substrate is disclosed that includes the steps of dissolving a vegetable oil ester based solvent wherein the ester is selected from a group consisting of esters having carbon chain length of C-1 to C-18 in a liquid solvent dye to form a low-sulfur containing dye formulation such that the vegetable oil ester is present in an amount of between about 5 and 80 percent by weight of the dye formulation, and mixing sufficient amounts of the dye formulation with the substrate to produce mixtures of predetermined color in which the levels of toxic substrate are substantially less than in otherwise equivalent mixtures that include hydrocarbon-based solvents.

Abstract: A dye formulation is disclosed that includes a vegetable oil ester based solvents that have carbon chain lengths of C-1 to C-18, a solvent dye that is a true liquid dye dissolved in the vegetable oil ester for imparting color to the dye formulation, and reduced sulfur levels in commercially available dye formulations as compared to those in hydrocarbon based solvent systems. Sulfur content is typically reduced to 2-3 percent of dye formulations in hydrocarbon based solvents. The formulations are particularly useful for tagging petroleum substrates as well as writing instrument and ink jet formulations.