Lightfast Inks - What are lightfast inks?

Definition of LIGHTFAST INKS:

Inks that are designed to resist fading when exposed to natural or artificial lighting. Exposure to light (including natural sunlight, direct sources of UV light, and artificial lighting like fluorescent light) can cause a reaction to occur in the pigments used in printing inks, which can lead to the colour fading or changing over time. Lightfast inks are usually chosen when the final product is to be stored or used outside or near to an artificial light source that could cause fading. Most inks have a lightfastness rating to indicate how long it takes for noticeable fading to occur in normal indoor conditions.

Here is the Harvard-style citation to use if you would like to reference this definition of the term lightfast inks:
Label Planet (2020) What are lightfast inks? | Lightfast Inks Definition. Available at: https://www.labelplanet.co.uk/glossary/lightfast-inks/ (Accessed: January 1, 2024).