System and methods for producing composite colors having improved saturation using pigment-based inks on generic media
AssigneeHewlett-Packard Development Company, L.P.
InventorSundar Vasudevan
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Abstract
A printing system has a substrate, and first and second colored inks. The first colored ink has particles of a first pigment, and the particles have a first net zeta potential. The second colored ink has particles of a second pigment and a polarity-reversing amount of a surfactant. The particles of the second pigment have a second net zeta potential opposite in polarity to the first net zeta potential. The first and second colored inks are configured to be printed together over a common surface of said substrate to form a composite color.
Claims20
A printing system comprising:
- a substrate;
- a first colored ink comprising particles of a first pigment, said particles comprising a first net zeta potential;
- a second colored ink comprising particles of a second pigment and a polarity-reversing amount of a surfactant, such that said particles of said second pigment comprise a second net zeta potential opposite in polarity to said first net zeta potential;
- wherein said first and second colored inks are configured to be printed together over a common surface of said substrate to form a composite color.
A method of printing a composite color with enhanced color saturation, comprising printing first and second colored inks together, said first colored ink having pigment particles of a first polarity and said second colored ink comprising a polarity-reversing amount of a surfactant such that said second colored ink comprises pigment particles of a second polarity opposite to said first polarity.
A method of preparing a colored ink for use in printing composite colors, comprising:
- providing an aqueous dispersion of pigment particles having a first net zeta potential;
- and
- adding a surfactant to said dispersion in a polarity-reversing amount;
- wherein said pigment particles obtain a new second net zeta potential opposite in polarity to said first net zeta potential.
Dependencies are inferred from the claim text.