Guilloche
A graphic element in the form of a complex geometrical pattern which consist of repeated thin curved lines formed according to certain mathematical rules. Guilloche elements form rosettes, frames, borders, vignettes and elements of a background pattern. Guilloche elements can be both positive and negative.
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b
Fig. 1. Russian Federation. Diplomatic passport issued in 1995:a — front endpaper. Paper substrate; b — the same. Negative (light-coloured, non-printed lines on the dark background) and positive (dark lines on the light-coloured background) guilloche. Intaglio printing
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b
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d
Fig. 2. The Czech Republic. Diplomatic passport issued in 2005:
a — page 17. Fragment of the background pattern formed by guilloche elements. Paper substrate; b — the same. Zoomed fragment. Guilloche. Offset printing; c — the same. Front endpaper. Vignette; d — the same. Zoomed fragment. Vignette. Intaglio printing