| 摘要 |
PURPOSE: Provided is a process for preparing a solvent-soluble purified dyestuff having high quality and low salt content, which is suitable for coloring paper, plastic, fabric, metal, and glass by an ink-jet method. CONSTITUTION: The process comprises the steps of: mixing an aqueous press cake of the dyestuff into a water-miscible liquid; distilling off water until a water content is less than 5wt%; filtering the dyestuff composition comprising the solvent-soluble dyestuff and the water-miscible liquid to remove all insoluble contaminants; diluting the dyestuff composition in de-ionized water to precipitate the solvent-soluble dyestuff and then filtering, isolating, and washing the solvent-soluble dyestuff.
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