Exposure of some digital print types to high humidity can cause image colorant migration resulting in image density changes, color shift, blurring and loss of detail. The purpose of this study was to quantify the potential for colorant bleed during short-term exposures to high humidity conditions in order to develop care and use guidelines for museums, libraries and archives that may collect large numbers of these materials including many of high monetary value. Most previous work has focused on image effects, but this project also includes tests for damage to text-based documents. The potential for bleed both parallel and perpendicular to the printer paper feed direction was examined. A variety of digitally printed materials, including inkjet, electrophotographic, and dye sublimation were exposed to high humidity conditions for two and four weeks. Results are reported as Delta E for a checkerboard target, change in width for lines both parallel and perpendicular to the paper feed direction, as well as text readability which was assessed visually. The relative sensitivities of the materials are ranked and compared to the sensitivities of traditionally printed offset lithography and chromogenic photo materials.
Eugene Salesin, Daniel Burge, Douglas Nishimura, Nino Gordeladze, "Short-Term High Humidity Bleed In Digital Reflection Prints" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP26), 2010, pp 386 - 389, https://doi.org/10.2352/ISSN.2169-4451.2010.26.1.art00005_2