Digital Prints

the inks tend to get lost in the paper’s fibers and look muddy. Most pigment inks are
designed to go on coated papers (Epson Durabrite pigments are an exception; they’re
designed for uncoated papers.).
■ A related issue with some pigments used on glossy or luster-type papers is smudging or
“rub-off” where the ink can smear, especially in darker or black areas. Newer pigment ink
formulations such as Epson’s microencapsulated inks that “stick” better to the paper have
attempted to fix this problem.
■ Pigment ink particles can separate or “settle out” over time, especially if the printer is not
used on a regular basis, and this can cause inconsistent printing including weak colors.
Tony Martin, President of ink supplier Lyson USA, has a couple of good analogies to illustrate
this: While dye inks are like Kool-Aid or apple juice that, once stirred, never separates
again, pigment inks are more like the sandy water in a river or at the beach. If you
look closely, you can see the particles of sand dispersed in the water. One easy solution to
the settling problem is to occasionally shake pigment ink carts or tanks, although Martin
advises that it is difficult to sufficiently re-disperse the pigments with this method so that
the ink returns completely to its original color intensity.
In theory, the basic trade-off between dyes and pigments has traditionally been: Dye-based
inks are more “colorful” on a wide range of media but also prone to being less stable or
permanent, while pigment-based inks may offer less color gamut, but they are more lightfast,
humidity fast, and gas fast (see Figure 7.4). In reality, the gap is closing, and ink manufacturers
are continually trying to come up with compromise solutions between color
gamut and permanence.
Dyes and pigments can also be mixed together for a specific result. For example, thirdparty
ink supplier MediaStreet.com has formulated its popular Generations brand (G4,
G5, G6 or G-Chrome) pigmented inks to include black-ink options that are 75-percent
pigment and 25-percent dye in order to boost density and visual richness. (The other
blacks and colors are all 100-percent pigment, and other Generations inksets still include
the 100-percent pigment black.) The only downside to such mixtures is that there can be
uneven results when one ink component changes or fades before another. MediaStreet,
however, claims that their hybrid blacks still exceed the same 100 years of display life
Chapter 7 ■ Choosing Your Consumables 217
Figure 7.4 Photoconservator Martin
Juergens’ view of the basic trade-offs
between inkjet dyes and pigments.
Courtesy of Martin Juergens