Piezochromism
The piezochromism is the property of solids, when exposed to pressure to change the color. This color change is usually reversible .
Gustav Kortüm describes piezochromism as follows: "This is a pressure-dependent thermodynamic equilibrium between two constellation isomeric forms of the molecules that are to be viewed as alternative forms of different energy content due to the not possible coplanar structure" . Piezochromy comes a. in polymers and is a subject of intensive research. Piezochromism is also found in minerals.
Piezochromic materials are said to be used in pressure sensors that display changing pressures through changes in color.
Individual evidence
- ↑ Gustav Kortüm: Thermochromy, Piezochromy, Photochromy and Photomagnetism . In: Angewandte Chemie . tape 77 , no. 1 , 1958, p. 14-20 , doi : 10.1002 / anie.19580700104 .
- ↑ Page of the Chromogenic Polymers Department at the Fraunhofer Institute for Applied Polymer Research ( Memento of the original from June 4, 2016 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed April 14, 2016.
- ↑ Karl Przibram : About Piezochromie (color change through pressure) in natural minerals . In: Communications from the Institute for Radium Research . No. 230 , 1929, pp. 263-269 ( PDF ).
- ↑ Patent DE102009035363 : Piezochromic material, piezochromic composite material and piezochromic sensor. Registered on July 30, 2009 , published on February 3, 2011 , applicant: Fraunhofer Society for the Promotion of Applied Research, inventors: Arno Seeboth, Ralf Ruhmann, Renate Vetter.