JPS6420439A - Humidity sensible element - Google Patents

Abstract

PURPOSE:To decrease a drift in a state that it is contrived to secure the sensitivity as a humidity sensible element, by forming a humidity sensible film by using a high polymer consisting essentially of ethyl cellulose. CONSTITUTION:A humidity sensible film 3 is formed by a humidity sensible material consisting essentially of ethyl cellulose EC especially, in a cellulose ether high polymer. The humidity sensible film 3 has the quality whose dielectric constant becomes large, although its adsorption moisture quantity is small, since the main component is EC. That is, as far as the EC is concerned, its adsorption site is much smaller or its hydrophilic property is weaker than an organic high polymer such as CAB, CAP, PAI, etc. The adsorption moisture quantity of the EC is a value which can secure enough the hydrophilic property being suitable for using it as a humidity sensible element of a capacity type, and also, since its adsorption moisture quantity is small, a more stable (drift is small) humidity sensible characteristic than a sensor on the market, using the CAB can be obtained with small hysteresis and with high response.