METHOD AND PREPARATION FOR REGENERATING BY CHEMICAL TREATMENT THE ORIGINAL HUE OF RED MARBLES OF TARDOS AND OTHER ORIGIN DISCOLOURED /LOST THEIR COLOUR/ UNDER THE INFLUENCE OF OUTDOOR LOAD

摘要

Preexisting conditions and hues of colour of faded and decayed red marble and hard limestone exposed to elements, are reconstituted by metallic salt solns. contg. mainly chromophore gps. Such solns. penetrate the surface layers and micropores of these stones deeply. Matching and stable colour development is a result of chemical action. As the chromophore cpds. formed are soon fading, the treatment does not have to be repeated even when several decades have passed. All original lines (yellowish, brownish, mauvish etc) may be developed without loss of original patterning and veining. Recolouration is followed by conventional consistency protection and surface conservation (e.g. hydrophobic surface development).