Abstract: A reaction product of a mixture of components suitable for molding into shaped desiccant particles, wherein the mixture includes: a. a porous siliceous material, b. hygroscopic salt, c. polyvinyl alcohol (PVA) with a degree of hydrolysis between 82 and 95 mol % and a viscosity between 12 and 40 mPa·s, as determined on an aqueous solution of 4% PVA at 20° C. according to DIN53015, d. water, e. optionally, an OH-containing polymer, different from PVA, wherein the weight ratio between hygroscopic salt and the porous siliceous material is chosen between 0.1:1 and 0.9:1 and wherein the weight ratio between hygroscopic salt and PVA is chosen between 1:1 and 5:1.

Abstract: The invention relates to a humidity indicating composition comprising (a) an organic pH indicator dye compound, (b) a Bronsted base comprising an organosilane, (c) a moisture-curable binder, (d) an optional rheology additive and (e) an optional alkaline filler.