Digital Prints

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Mastering Digital Printing
the subject of this book, whether dye- or pigment-based—all Epson inks are aqueous.
(Solvent-based printers are preferred for various types of commercial and sign making
applications and are sometimes used for fine art.)
Added to the water base are other ingredients or additives such as humectants, surfactants,
and penetrants that help the inks perform better in an inkjet-printing environment.
The colorant (technically called dyestuffs) gives the ink its color. Based on what we’ve
already learned, the colorant of an ink absorbs certain wavelengths of visible light and
reflects others that are then perceived by our eyes as color. Colorants come in two basic
types for inkjet printing: dyes and pigments, and each has its strengths and weaknesses. See
Figure 7.1 for a visual comparison of the two types.
Figure 7.1 These two microscopic views show the difference between dye-based and pigment inks. Left: Dyes interact with the paper to form a uniform surface.
Right: Pigment particles form a thick film on the surface of the paper.
Courtesy of Hewlett-Packard Company
Dye-Based Inks
The first inkjet inks used for photography and fine art were water-soluble dyes. In fact,
some early artists even experimented with running food coloring through their IRIS printers!
Dye-based inks are still a large part of inkjet printing. All thermal desktops (Canon,
HP, Lexark) come ready to print with dye-based inks. Epson desktops come either in dye
or pigment types.
Dyes are made up of extremely small, individual colorant molecules, and because they
penetrate below the surface of the paper coating, dye-based inks provide excellent image
quality with rich color depth and a gloss that’s usually more uniform than with pigments.
Dyes also work very well on uncoated fine-art papers that absorb the ink; the ink droplets
bleed a little and tend to cover up certain printer-based problems like low dpi resolution.
The main disadvantages of using dyes for printing are higher susceptibility to light fading
(in most cases), higher susceptibility to humidity influences(in most cases), higher susceptibility
to environmental gases, like ozone (in most cases), and greater variability of
longevity with differing media