Förfarande för framställning av fuktutbyteselement

摘要

Moisture exchange element (I) is obtd. by (i) impregnating a substrate (II) with an aq. soln. contg. 5-20 wt.% colloidal SiO2, 0.25-2.5% of H2O soluble metallic salt plus an acid to keep pH of at 5-9 then (ii) drying and gelatinising the soln. deposited on (II) to form an absorbent of larger than 20 angstrom pore size on (II).