CONCENTRATION DETECTION ELEMENT FOR SOLUTE IN AQUEOUS SOLUTION.

摘要

The invention gives a solute in an aq. soln. concn. detection element sealed airtight by a porous non-water-permeable fluororesin film or a two-layered film of a porous non-water-permeable fluororesin film and a selective vapour-permeable layer or a three-layered film of a porous non-water-permeable fluororesin film, a selective vapour-permeable layer and an acid vapour absorption layer, by using the property where the concn. of a solute in an aq. soln. is closely associated with the vapour pressure of the aq. soln.