Titanium-based tinplate for canning foods.

摘要

Cr-based treatments are currently used for the passivation of tinplate for use in canning, which produces a protective surface layer consisting of a mixture of metallic Cr and chromium oxide. This passivation film is effective against the formation of tin oxides and corrosion by foods, and provides a good substrate for the adhesion of protective organic coatings. However, there is increasing concern about the environmental and health risks associated with this passivation treatment. The aim of this study was to investigate a new environmentally friendly passivation treatment based on a Ti compound, applied on tinplate and subsequently lacquered with a conventional epoxyphenolic lacquer used for food can applications. The mechanical and electrochemical characteristics of the lacquered material and metal dissolution in canned sardines in tomato juice and peeled tomato were determined and found to be similar to those obtained with conventional Cr-passivated tinplate. It is therefore suggested that Ti treatment could be used as an alternative to Cr.