Energy efficient thermotropic foils

Glaring sunlight and overheated rooms - a remedy can be provided by a special foil that is placed between the window panes and takes over the heat regulation. The foil achieves this with embedded particles that scatter the incident light. If the solar radiation increases, the foil reduces the incidence of light.

The invention relates to doping capsules containing a substance which exhibits a decreasing transparency in a defined temperature range as the temperature rises, by physicochemical interaction with the polymer matrix to be doped. The invention also relates to composite systems that have a polymer matrix doped with the doping capsules. The capsules according to the invention can be used for sun-protection or thermal reflection applications.

WO 2009/080232 A2

This project is funded by Fraunhofer-Gesellschaft