Color-Changing Thermochromic Pumpkin
It works like magic: touch the pumpkin and the handprint left behind changes from one color to another before your eyes. Our secret? An ingredient called "thermochromic pigment."
This idea comes from Digital Editor Alexandra Churchill. It changes color due to a change in temperature, which is a property called "thermochromism" and it can be applied on a number of surfaces including pumpkins. The fine, colored powder — also known as "thermochromic pigment" — changes to a clear powder when heated to 77 degrees. The process is also reversible: when it gets cold, the pigment returns to its original color. This specialty pigment can be combined with almost any clear binder such as glue, varnishes, or resins to produce a paint. However, it is recommended to use a clear binder with neutral PH 7; an acidic or alkaline binder can destroy the fine microstructure of the pigment.
Tip: To extend the life of your color-changing pumpkin, we recommend keeping it in a cool environment out of direct sunlight. Overexposure to light and the overuse of solvents may cause expedited fading.