Impact on Surface Treatment of Hydrophobic Consolidation Terracotta Ornaments

Abstract

During the consolidation and rehabilitation interventions of George RaduMelidon City Library Roman, Neamţ County, a series of architectural terracotta decorations, manufactured in the second half of the century XIX, have been identified and cataloged. The current state of these decorations, made from geomaterials, requires the establishment of a technical solution which will be used to preserve, to strengthen the color, the aesthetic surface and the chromatic reintegration. Thus, the paper presents the study of four current commercial chemicals products, part of the additives hydrophobic/waterproofing group. One of the products is a water based emulsion, while the other three are organic based solvents. This study was required in order to develop an optimal treatment to preserve the old terracotta from facade of building already mentioned. The technical features that these products have in common are sealing and waterproofing by superficial coating, with an average penetration and restoration of chromatic aspect, as close to the original. CIE L*a*b* colorimetry, optical microscopy and the measure of humidity (reversible water content and related chemical) were implemented in the study of optimization of pellicle dispersion systems based on the four chemicals.