Large‐Scale Roll‐to‐Roll Patterned Oxygen Indicators for Modified Atmosphere Packages

We demonstrate roll‐to‐roll fabrication of ultraviolet A light‐activated colorimetric oxygen indicators on paper and plastic substrates. Such large‐scale, cost‐effective and non‐toxic oxygen indicator and production method can find applications as a very low‐cost leakage indicator for modified atmosphere packages by printing the material directly or gluing the pre‐printed indicator label inside the lid. The introduction of leakage indicators onto all modified atmosphere packages could result in improved food safety and reduced food spoilage. Copyright © 2017 John Wiley & Sons, Ltd. A roll‐to‐roll fabrication of large‐scale, cost‐effective, non‐toxic and ultraviolet A (UVA) light‐activated colorimetric oxygen indicators is demonstrated on paper and plastic substrates. The UVA light patterned structures presented in the graphical table resulted in the maximum contrast from 80% to 1% reflectivity between the UVA exposed to the UVA unexposed areas, respectively. The developed roll‐to‐roll printed oxygen indicators are expected to find many applications in safe and smart packaging in the futures.