PROCEDURE FOR THE PRODUCTION AND USE OF PORCELAIN STONEWARE TILES WITH ANTIBACTERIAL ACTIVITY

摘要

The present invention describes the production process to obtain porcelain stoneware tiles with antibacterial action. The material promotes the bacteria's death, while all the other required technological characteristics, particularly the chemical resistance and anti-staining properties, are assured. The product is made from a porcelain stoneware paste with a black ceramic pigment containing iron and chromium in its composition; the deposition, by jet spraying, of a small layer of a transparent glaze (typically used to enhance the surface characteristics) and the firing schedule is similar to that used to obtain similar products. Once fired, a chemical (sodium nitrate and silver nitrate solution) and thermal (at 4300C) treatment is optionally carried out. Under optimized conditions the material shows effective antibacterial action: killing of 77% S. Aureus bacteria and 81% E. Coli bacteria, i.e., the survival percentage of the tested bacteria is only about 20%.