Watermark
A watermark is made during paper production by means of various thicknesses of paper – either thicker or thinner than the surrounding material – which results in a gray-toned image being visible. For banknotes, the cylinder mould process is used to apply watermarks that appear three-dimensional.
Watermark, allover
Watermark motifs evenly allocated over the whole surface of a paper.
Watermark, cylinder mould
Watermark, electrotype
See Watermark, HighLight.
Watermark, fourdrinier
Also referred to as a moulette watermark, produced with fourdrinier paper machines, in which after sheet formation the nonwoven fibers are compressed or displaced into characters via a forming roll with images. In transmitted light, the result appears as a simple light/dark watermark. One typical application is for commercially available printing and writing paper.
Watermark, HighLight
Synonym for electrotype, e-type, watermark; generated during the sheet formation process and serves to especially highlight important information. This type of watermark is very light (because it is thin) and clear (because it is “sharply defined”). Example: indication of the value of the banknote within the watermark on euro banknotes.
Window thread
A security thread embedded in the banknote and appearing on the paper's surface at defined points on the banknote (windows). When viewed straight on the security thread is partially visible, and appears across the entire length in transmitted light.