Intelligent printing

What? Thermochromic ink on the can of soda drink Cockta (the first commercial non-alcoholic drink in Yugoslavia, produced from 1953).

Where? On the market – Slovenia.

When? Appearing from 2010.

More details: The snowflake becomes clearly visible when its background changes to blue. The colour change occurs within  7-12°C with very narrow histeresis loop (~1.5°C).