Scratch and sniff technology generally refers to things that have been treated with a microfragrance coating. When scratched, the coating releases an odor that is normally related to an image being displayed under the coating. The technology has been used on a variety of surfaces from stickers to compact discs. Stickers became common in the late 1970s, and grew into big business for several companies throughout the early and mid-1980s. As the technology evolved to an ‘acid-free’ design the sticker craze seemed to come to a close.
Utility companies have sometimes enclosed scratch and sniff cards in their bills to educate the public on recognizing the smell of a methane gas leak. However, this sometimes would lead to a rash of false alarms as the scent emanating from a discarded scratch and sniff is later mistaken for a real gas leak. Scratch and sniff is created through the process of micro-encapsulation. The desired smell is surrounded by micro-capsules that break easily upon scratching. Because of the micro-encapsulation, the aroma can be preserved for extremely long periods of time.
The Daily Omnivore 
Leave a comment