Commercial thermochromic products

The commercial thermochromic products include multi-components, namely the colour former, an acidic catalyst and a non-polar co-solvent medium. The organic thermochromic materials are easy to obtain and cheaper than thermochromic liquid crystal, but they are not sensitive and their colour change range is narrow. These materials can be used on some thermochromic printing without high quality demands. 

White, M.A., 1999. Thermochromism in commercial products. Journal of Chemical Education 76 (9), 1201-1205. 

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