Substancje uniemożliwiające odbiór dzieła plastycznego w malarstwie ściennym

Murals are co a ted by a ssorted fo r eign substances ow in g to in ten tion a l human activity or natural p ro cesses o f the se ttlem en t o f impurities and the crystallisation o f salt. Such substances render the r e c ep tion o f the w o rk o f art illegible or even im p o ssib le , and thus are rem o v ed in the course o f c on se rv a tion . Foreign substances are d ivided into: b u ild -u p , w h ich en c om p a ss e s p a in tin g , plastering, the use o f w all paint and artistic o v e rp a in tin g , and co a tin g w ith varnish and fix in g agents; a ccre tion o n the p a in ted surface in the form o f dust; o rganic im pu rities, i. e. p lan t o rganisms and substances a sso c iated w ith the p resen c e o f animals; and salt e fflo r e sc en c e , i. e. substances crystallised on mural surfaces.