from the conferences organized by TANGER Ltd.
The set of five bronze vessels from the Late Bronze Age was found near to the Lidice village in 2014. The copper (I) chloride - nantokite was identified in a mixture of corrosion products. Nantokite is exposed to the surrounding atmosphere after excavation of the bronze vessels from a soil. Nantokite reacts with moisture and oxygen in the air to form basic copper chlorides. Basic copper chlorides have a larger volume than nantokite. The volume change of corrosion products leads to disintegration of metal core along the grain boundaries. Such a type of bronze corrosion damage is called bronze disease. The aim of the study was to suggest preservation coating system with the lowest oxygen permeability. The acrylic based lacquers (Paraloid B72 and Paraloid B48N), waxes (beeswax and microcrystalline wax) and corrosion inhibitor 1,2,3-Benzotriazole (BTA) were tested. Efficiency of monolayer and double layer preservation systems was compared. The double layer preservation system has performed the lowest oxygen permeability compared with the other tested substances. The inner layer is formed of the acrylic lacquer Paraloid B48N with addition of BTA and an outer layer is made of the microcrystalline wax with BTA addition.
Keywords: Copper alloys, preservation, lacquer, wax, oxygen permeability© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.