The Cracking of Inkjet Colorant Receiver Layers on Exposure to Light

Abstract

The purpose of this investigation was to determine whether exposure to light or ozone increases the sensitivity of some inkjetprinted images to surface cracking during handling. In previous studies, several inkjet print examples showed a potential for significant cracking and flaking of the image area when handled after exposure to light and ozone. In these new experiments both printed and unprinted samples of two glossy porous photo inkjet papers from different manufacturers were exposed in separate experiments to 50 kilo-lux fluorescent and 50 kilo-lux xenon light in increments of time for up to twelve weeks and to 5 ppm ozone for one and two weeks. The exposed samples were tested for cracking according to the procedure described in ISO 18907 "Imaging Materials-Photographic Films and Papers-Wedge Test for Brittleness". The samples were evaluated visually both with and without magnification to determine the wedge diameter where cracking is first seen. The samples were also measured with a Gretag Spectroscan to determine if the increase in cracking came before or after noticeable colorant fade or paper yellowing occurred. Even though the two papers selected for this study were the same type, they behaved entirely differently. One paper showed sensitivity to crack before exposure and increasing propensity to crack with exposure to light and ozone. The other paper was not sensitive to crack before exposure and only after twelve weeks exposure to xenon light showed surface disintegration. Because of this, it is difficult to reach general conclusions that represent the entire spectrum of inkjet print media. Additional work is needed to provide a more complete picture of brittleness behavior of these materials after exposure to light and ozone.

Light-induced cracking and abrasion of inkjet prints: Damage and mitigation

“…Similarly, previous work showed that, when exposed to light, inkjet photo-porous papers printed with pigments can crack and/or delaminate before colorant fade is noticeable (Salesin & Burge, 2012a). The lack of visible signs of change may lead the user to assume a print is undamaged; this increases the risk of physical damage to the print during handling.…”

“…Previous DP3 studies determined that certain digital print types are prone to cracking and abrasion , and that factors such as low relative humidity (RH), pollutants, and light increase the tendency to crack of the IRL in some inkjet prints Burge et al, 2010;Salesin & Burge, 2012a). The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings ( plain glass and UV-filtering glass) to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum.…”

Mitigation of light-induced damage on modern digital prints: Photographs and documents

“…Unexposedleft; exposed with UV glass -center-left; exposed with plain glass -center-right; and exposed without glazing -right. Light has been shown to induce or increase the cracking of the ink-receiving layer of inkjet prints (Salesin & Burge, 2012). In the same way, light may increase the tendency of some digital prints to abrade or scratch.…”