GASEOUS MEDIUM CAPACITIVE MOISTURE CONTENT SENSOR Russian patent published in 2016 - IPC G01N27/22 

FIELD: measuring equipment.

SUBSTANCE: invention relates to gases moisture content measuring equipment. Capacitive humidity sensor has sensitive capacitor-type element consisting of dielectric substrate, lower electrode from corrosion-resistant metal or alloy, upper nano-structured electrode from corrosion-resistant metal or alloy, permeable for moisture vapors, and moisture-sensitive layer having dielectric constant, changing depending on water vapors amount in environment. At that, invention uses preset thickness upper electrode from nano-structured corrosion-resistant metal, permeable for moisture vapors and formed by laser electro-dispersion method, as well as moisture-sensitive layer is high-heat-resistant photosensitive polymer composition based on poly(o-hydroxy amide) - product of 4,4′-diamino-3,3′-dihydroxy diphenylmethane polycondensation with isophthalic acid bichloride, light-sensitive component - naphthoquinone diazide derivative and amide type solvent at following ratio of components, wt%: poly(o-hydroxy amide) 12-15; light-sensitive component 2.4-3; amide solvent - the rest. Obtained textured microporous moisture-sensitive layer is highly hydrophobic and withstands heating to 400 °C in air and 450 °C in inert atmosphere.

EFFECT: upper electrode structure ensures unobstructed moisture access to dielectric and has high adhesion to located below dielectric.

1 cl, 1 tbl, 4 dwg, 6 ex