LABORATORY: CNR ISPC
NAME OF THE INSTRUMENT
Contact sponge
GENERAL DESCRIPTION
The contact sponge method is based on the measurement of the amount of water absorbed by the side of a porous material.
Such amount of water absorbed is determined by difference, weighing not the substrate (enhancement of weight, absorption), but the sponge (decrease of weight, desorption).
TECHNICAL DESCRIPTION
The contact sponge method is a water absorption test by side of the studied material that can be performed also in situ.
A sponge having preset characteristics and dimensions is charged with an adequate amount of water (when in contact with the surface, it has not to leak). For the application on the examined surface, a circular plastic plate is used. The amount of water absorbed by the surface is calculated by difference, weighing the sponge before and after the application. The precision of the measurements directly depends on the precision of the used balance.
APPLICATIONS
The contact sponge method is easy to apply in situ, unlike other water absorption methods. Water absorptions measurements are very widespread because they are useful for the evaluation of the conservation state of a surface and of the performance of conservative treatments, in particular protective ones
Referent:
Silvia Rescic silvia.rescic@cnr.it