Diterawang — held to light
Security thread
A thread that sits inside the substrate rather than printed on its surface.
The thread lies between the layers of the substrate and surfaces only at intervals. So it looks interrupted from outside, and whole once light passes through the sheet.
- The thread is embedded within the material, so it cannot be peeled or rubbed off the surface.
- At intervals the thread rises to the surface. These are the short segments visible in ordinary light.
- Held to the light, light passes through the substrate but is stopped by the thread, so its full length reads as one continuous dark line.
What to observe
- A security thread is present on the Rp100,000, Rp50,000, and Rp20,000 notes. On the Rp100,000 and Rp50,000 it changes colour when viewed from a different angle.
- Held to the light, the thread reads as one continuous line running edge to edge, unbroken.
- In ordinary light only short segments show at the surface. The difference between segments and one whole line is what is being checked.
This page explains how to check a feature, not how one is produced. Nor does this site say whether any note is genuine — that authority rests with Bank Indonesia.
Sources
- Bank Indonesia — Gambar Uang — Rp100.000 Tahun Emisi 2016, Unsur Pengaman ↗open source: Gambar Uang — Rp100.000 Tahun Emisi 2016
- Artech House — R. L. van Renesse, Optical Document Security, 3rd edition (2005), Ch. 4, Security threads