Visual Indicator of Pressure or Temperature
Original Publication Date: 1980-Apr-01
Included in the Prior Art Database: 2005-Feb-13
A film of the organic charge-transfer solid TTF-CHL (tetrathiafulvalene-chloranil) changes color sharply from yellow to red above a certain critical pressure, as well as below a certain critical temperature. We propose to use films of TTF-CHL (or other materials showing the same effect) as a visual indicator to monitor pressure or temperature. When the pressure or temperature exceeds (or falls below) the desired critical value, it is indicated by the marked change in color of the film.