In the past two decades, 3D printing using polylactic acid (PLA) and other plastics has become widely used for modeling, prototyping, and manufacturing, for both professional and amateur applications. Statistics website <www.statista.com> predicts that the global 3D printing market will grow from $12 billion in 2018 to $20 billion in 2021. Like 2D-printed signs, prints, and photos, 3D-printed objects, if placed outdoors or in windows, will be exposed to visible light and UV radiation that can cause colorant fading, surface chalking, crazing, and other degradation (including a loss of brightness in the case of fluorescing colors). Little recent work has been published concerning testing of 3D-printed materials for light fading, ozone resistance, and the long-term dark storage stability. [1] To develop a protocol for permanence testing of 3D-printed objects, the authors first developed a 3D-printable test target inspired by the widely-used Macbeth ColorChecker. Fade-resistance testing of samples placed in the 3D color test target was conducted under accelerated fluorescent illumination and in outdoor sunlight.
Richard M. Adams II, Henry G. Wilhelm, "Permanence Testing of 3D-Printed Objects Subjected to Fade Testing with Outdoor Sunlight and with High-Intensity Fluorescent Illumination and Evaluated with a Multispectral Camera and Image Analysis System" in Proc. IS&T Printing for Fabrication: Int'l Conf. on Digital Printing Technologies (NIP34), 2018, pp 170 - 175, https://doi.org/10.2352/ISSN.2169-4451.2018.34.170