Digital hard copy output has increased dramatically as an alternative to traditional imaging systems. From family pictures output by home computers to commercial signage and art reproduction, companies are rushing to get a piece of the digital pie. At first, the problems of resolution, printing technology, color reproduction and digital capture were the center of attention. With advances in solving these issues and the resulting increase in demand for the new products come new questions. A customer will marvel at the ease of use, the acceptable image quality and speed of editing, but now that same customer will ask, “How long is it going to last?”.In the digital world, new output technology, new ink sets for existing devices and new media are appearing every day. With these developments comes the need to reassure the consumer that the new products will have a usable life adequate to the proposed application. In traditional photography, there is a battery of accelerated tests to compare and predict life expectancy of both the image and the support. Until now, tests of digital hard copy materials have had to rely on the precedents established by the photo industry. The Image Permanence Institute has constructed a high-intensity (50 to 100 klx) fluorescent light-fading apparatus aimed at giving fast answers to questions about display life of digital hard copy output images. After comparative tests at different light intensities, it has been determined that some inkjet materials do not suffer from reciprocity law failure common to photographic materials. This means that high-intensity, short-term tests can be a reliable indicator of long-term stability in these materials.
Edward Zinn, Douglas W. Nishimura, James Reilly, "High-Intensity Fluorescent Light-Fading Tests for Digital Output Materials" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP15), 1999, pp 416 - 420, https://doi.org/10.2352/ISSN.2169-4451.1999.15.1.art00012_2