Relative humidity sensor

Abstract

Abstract An essentially full range resistance type relative humidity sensing element is produced by providing a dielectric blank, on which an electrode system has been applied, with a metal oxide coating, in a manner which produces a porous structure therein, and subsequently impregnating that coating with a humectant material. The metal oxide used is selected from a group, including oxides of the metals found in Group VIII, Period 4 of the Periodic Table, which exhibit electrical insulating properties, and wherein the amount of electrical resistance varies with the relative humidity of the environment to which it is exposed. The humectant material, which may be any nonvolatile, reversibly hygroscopic material capable of being retained in the porous oxide structure, such as polyethylene glycol, for example, reduces both the amount of electrical resistance and the magnitude of the change in that resistance produced in response to changes in relative humidity into a range readily measured by ordinary electrical resistance measuring devices.

Inventors

• 👤 M Nicholas

Bibliographic Details