The purpose of this study was to survey the most common types of digital print materials to determine their resistance to fade or yellowing by nitrogen dioxide (NO2), a pollutant commonly found in indoor environments to different degrees. For this experiment, various types of inkjet, dye sublimation, and electrophotographic prints (including digital press) were exposed to 5 ppm NO2 for four weeks. The sensitivities of the digital prints were then compared to those of traditionally printed materials (black-and-white electrophotographic, color photographic, and offset lithographic). Inkjet dye inks and the color dyes in traditional photographic prints were the most prone to fade by NO2. Traditional photographic, digital press, and offset lithographic papers were the most prone to yellowing by NO2. Black colorants were fairly robust indicating that most text-only documents should be very resistant to NO2 induced fade, though the papers may still yellow. Additionally, some inkjet dyes bled slightly to severely, depending on the printer and paper combination, causing the prints to appear discolored and blurred. This could result in loss of detail in images or a reduction in the readability of text in documents. This effect has not been reported with ozone exposures.
Daniel Burge, Nino Gordeladze, Jean-Louis Bigourdan, Douglas Nishimura, "Effects of Nitrogen Dioxide on the Various Digital Print Technologies: Photographs and Documents" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP27), 2011, pp 205 - 208, https://doi.org/10.2352/ISSN.2169-4451.2011.27.1.art00052_1