Application of rhodamine B as thermochromic sensor for evaluation of performance of cold paint.

A thermochromic pigment, derived from reaction of ethylenediamine and rhodamine B known as MA-RB, has been successfully developed. This pigment showcases temperature-controlled visible color-transformation properties in both solid and solution states. The thermochromic pigment MA-RB exhibits a notable color change from light pink to rose red, triggered by thermal excitation. In its solid form, MA-RB also displays thermochromic behavior, shifting its color from pink to rose red when exposed to visible light. MA-RB distinct thermochromic properties, characterized by visible color changes, make it a promising material for applications in both solid and liquid systems. Its ability to respond to temperature changes makes it an attractive option for coatings, offering a non-intrusive alternative for temperature measurement. It is successfully applied to measure the performance of cold paint which contains coumarin derivate as cold pigment. This can open a new filed in application of thermochromic pigments in energy systems such as smart windows, wearable fabrics, etc. or in measurement devices of temperature.