Security Thread
For the banknotes on the paper basis:
A narrow strip on the polymer basis incorporated into the paper substrate during the manufacturing process of the paper.
Classification
Location in the paper:
- Latent (solid) security thread is located completely in the paper and can be seen in transmitted light only (fig. 1);
- Diving (window) security thread can be seen on the paper surface as rectangles which form a dot line on the banknote surface and a solid line when viewed against light (fig. 2);
- Figured security thread appears partially on the paper surface as a figured window and as a solid strip when viewed against light (fig. 3).
a
b
Fig. 1. Latent.
2 000 Iceland Kronur (1986)
a – reflected light; b – transmitted light
a
b
Fig. 2. Window.
50 Swaziland Emalangeni (1995)
a – reflected light; b – transmitted light
a
b
Fig. 3. Figured.
1 000 Russian Rubles (1997). Modification 2010
a – reflected light; b – transmitted light
Materials and security features:
- Metallized without texts (fig. 4, a);
- Metallized with microtext applied by demetalization (fig. 4, b);
- Semi-transparent with texts (fig. 5);
- Holographic (fig. 6);
- Colour-changing (fig. 7);
a
b
Fig. 4. Metallized. Transmitted light:
a – without texts. 2 000 Iceland Kronur (1986);
b – with microtext. 50 Swaziland Emalangeni (1995)
Fig. 5. Semi- transparent with microtext. Transmitted light.
10 UAE Dirhams (1982)
Fig. 6. Holographic. Reflected light.
200 Nigerian Naira (2000)
a
b
Fig. 7. Colour changing. 50 Libyan Dinars (2008):
a – at right angles; b – at an acute angle
- Luminescent under UV light;
- With magnetic properties;
- With the “floating” Motion image: when inclining the banknote, the images on the security thread are moving perpendicular to the direction of inclination (fig. 8);
- With the optically variable effect “Scate”: the image disappears from the security thread at a certain angle of view and leaves iridescent tints of the hologram (fig. 9);
a
b
Fig. 8. Motion effect. 100 000 Lebanese Pounds (2011)
a – at right angles; b – at an acute angle
a
b
Fig. 9. Optically variable effect “scate”.
500 Russian Rubles (1997). Modification (2010)
a – at right angles; b – at an acute angle
- With the optically variable effect “Chameleon”: the images applied on the security thread look positive under reflected light and negative in transmitted light (fig. 10);
- With the kinetic effect “Mobile”: when changing the angle of view, certain images shift relative to each other (fig. 11).
a
b
Fig. 10. Optically variable effect “Chameleon”.
1 000 Russian Rubles (1997). Modification 2010:
a – under reflected light; b – in transmitted light
Fig. 11. Kinetic effect “Mobile”.
5 000 Russian Rubles (1997). Modification 2010:
at different acute angles
For banknotes on the polymer basis
An image in the form of a narrow dark or light semi-transparent strip printed on the surface of the polymer substrate.
It may contain microprinting, special inks with magnetic properties and other security features (fig. 12, fig. 13).
a
b
Fig. 12. Dark thread without microtext. 20 Dominican Pesos (2009)
a – transmitted light; b – zoomed image in transmitted light
a
b
Fig. 13. Light thread with microtext. 10 Taka of Bangladesh (2000)
a – transmitted light; b – zoomed image in transmitted light