MOISTURE-SENSING RESISTANCE MATERIAL AND MOISTURE SENSOR USING IT

摘要

PROBLEM TO BE SOLVED: To provide a moisture-sending material that has small aging of moisturesensing characteristics even if being exposed to a measurement atmosphere for a long time continuously and can measure moisture accurately, and a moisture sensor using it. ;SOLUTION: A moisture sensor 1 is provided with a ceramic substrate 2, at least two electrodes 3 and 4 being formed on the ceramic substrate 2, and a moisture-sensing resistance layer 7 that is formed so that it spans at least those two electrodes 3 and 4. Then, the moisture-sensing resistance layer 7 mainly consists of Na constituent, Ti constituent, and Si constituent that exist in an oxide form each, and is made of a moisture-sensing resistance material that is constituted as a porous ceramic body containing 7-25 mol.% Na constituent in terms of Na₂O, 10-65 mol.% Ti constituent in terms of TiO₂, and 5-60 mol.% in terms of SiO₂. The moisture-sensing resistance material shows an electrical resistance value level suited for the measurement of moisture and has a smaller aging of moisture-sensing characteristics when being used continuously for a long time as the moisture-sensing part of the moisture sensor. As a result, even if the sensor is used continuously for a long time, moisture can be measured accurately and stably.;COPYRIGHT: (C)1999,JPO