Thermobatch is a thermochromic plastic masterbatch material. That means it is a raw material, which comes in the form of coloured pellets, used for creating interactive plastic products that can change colour reversibly when exposed to a set temperature.

The Thermobatch manufacturing process is based on thermochromic microcapsules which are dispersed in a polymer vehicle. The most common vehicles for mixing with the thermobatch to create colour changing plastic materials are polyolefin and polystyrene, as well as thermoplastic elastomers and thermoplastic polyurethanes. Other vehicles can be considered for carrying the pigments. The Thermobatch material is manufactured by including Chromazone thermochromic microcapsules in either LDPE or EVA polymers through an extrusion process.

Depending on the required effect, the reversible colour change can be set to go either from a darker colour to a lighter colour on heating or from a lighter colour to a darker colour on cooling. An example is the blue sample shown. With a hand used as a heat source, touching the blue coating turns the colour off. Many colour changes are available: purple to pink or green to yellow, etc. In the opposite direction, in which the material changes colour to show a cooling, a fridge or freezer can demonstrate a colour change from yellow to green or pink to purple or white to blue, to indicate when a product or compartment is cold enough.

The user can interact with the colour-changing products. The interaction literally materialises information about temperature and, in set conditions, it more precisely indicates whether a particular product is at the right temperature conditions for use.

Colours available are blue, black, brown, green, magenta, orange, pink, purple, red, turquoise and yellow. These can all clear (i.e. turn blank or white) on heating and all are also available for colour-to-colour combinations such as purple to pink or green to yellow. The material is suitable for interior use only.