carbon-film hygrometer element

carbon-film hygrometer element

[′kär·bən ‚film hī′gräm·əd·ər ‚el·ə·mənt]
(electricity)
An electrical hygrometer element constructed of a plastic strip coated with a film of carbon black dispersed in a hygroscopic binder; variations in atmospheric moisture content vary the volume of the binder and thus change the resistance of the carbon coating.