Abstract: The invention relates to a marker solution which is to be applied by means of an inkjet printer and contains (i) at least one organic solvent that has a greater steam pressure than water at 20° C. and a water content of less than 50 percent (v/v), (ii) predefined first synthetically produced nucleic acids, and (iii) a nucleic acid-complexing, organic auxiliary agent as components.

Abstract: Chroma is increased, color-to-color bleed is reduced, and edge acuity is increase for dye-based inks by an underprinting technique. A dye-based ink-jet ink printing system is provided, comprising cyan, yellow, and magenta inks, each ink contained in a separate ink pen. Each ink contains at least one water-soluble dye and vesicles. The vesicles are present in an amount sufficient to contain a substantial fraction of dye molecules within the water pool of the vesicles. The vesicles formed from a surfactant having a first polarity. The printing system further comprises an additional pen containing a fixer having a second polarity, opposite to the first polarity. Further, an ink-jet printer that includes the dye-based ink-jet ink printing system is configured to print the fixer on a print medium, followed by printing at least one ink on the fixer. A method for improving chroma, color-to-color bleed, and edge acuity in a dye-based ink-jet ink.