- Thermochromatic ink
Thermochromatic ink is a type of
dye that changes color whentemperatures increase or decrease.Often used in the manufacture of many toys or product packaging, as well as thermometers.
Thermochromatic ink can also turn
transparent when heat is applied, an example of this type of thermochromatic ink is found on corners of anexamination mark sheet. This proves that the sheet has not been edited orphotocopied .
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