Digital Prints

Temperature
Any student of chemistry knows that as the temperature goes up, chemical reactions speed
up as well. So it stands to reason that a photochemical reaction such as light fading will
be accelerated by higher temperatures. Studies have found this to be true in general. High
humidity also frequently aggravates the situation. Extremely low temperatures, on the
other hand, can also be a problem when some materials will become brittle or even crack.
What Can Happen?
■ Color fading
■ Increased yellowing, especially in light or paper-white areas
■ Dye migration causing uneven densities and color hue shifts
Water & Humidity
Water in its liquid form or as moisture in the air can have a big—negative—impact on
prints, primarily those made with dye-based inks and/or on non-porous surfaces. Water
dripping, spills, water leaks, flood damage—these are just some of the most obvious potential
problems. The original, uncoated IRIS prints were so sensitive to moisture that
unknowledgeable framers ruined prints with only their own saliva while talking near them!
High humidity can also cause problems and is often linked with higher temperatures to
make things even worse.
Chapter 5 ■ Determining Print Permanence 149
Figure 5.1 The print on the left was
displayed on a wall for nine months
with a standard glass covering in a
frame. The one on the right is exactly
the same except it was framed without
glass. The increased fading is probably
due to UV exposure and/or
atmospheric contamination. Scientists
at the U.S. National Bureau of
Standards (NBS) found that UV
wavelengths were about three times
more damaging than the visible
spectrum. The graph at bottom shows
the NBS relationship between the
wavelength of the radiation and the
resulting relative damage. This helps
explain why even standard window
glass (with a UV cutoff at around 330
nm) is effective in slowing down
fading, at least to some extent.
Courtesy of inkjetART.com