Although cracking of image layers and/or buckling of papers is a potential problem for some digital prints under adverse handling conditions, there has been little investigation of this behavior. This study reports the results of using the ISO standard Wedge Brittleness Test, originally developed for traditional photographic films and papers, to explore the relative sensitivities of a variety of digital print types at 23°C/15% RH and 50% RH. The quantitative measurement in this test is the largest diameter in a wedge at which cracking or buckling first occurs. This method proved to be suitable for digital prints and allowed the examination of specimens for cracks and buckling. Some prints required very close examination after being subjected to the applied stress because many of the resulting defects were microscopic. The relative severity of the resulting damage is also discussed. Results are reported for over two dozen unprinted papers as well as mid-density prints produced by ink jet, dye diffusion thermal transfer, offset lithography and electrophotographic printing methods as well as by the traditional wet chemical process. There were wide differences in behavior between materials. In general, as might be expected, damage was more severe with some papers at the lower humidity condition.
Eugene Salesin, Daniel Burge, Peter Adelstein, James Reilly, "Brittleness of Digital Reflection Prints" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP25), 2009, pp 138 - 141, https://doi.org/10.2352/ISSN.2169-4451.2009.25.1.art00039_1