How well are the upgraded banknotes protected from dirtying?

The both sides of the upgraded banknotes are covered with a microscopic layer of varnish, which protects the banknotes from dirtying and deterioration. Apart varnishing, the banknotes are protected from dirtying also by the relief printed images and texts.

Almost all the main images and texts, as well as edge ornaments of the upgraded banknotes are relief printed.