Aster4Note®
Polish Security Printing Works (Poland)
Type: Optically variable printed or foil security element — intaglio-embossed structure producing dynamic visual effects
Overview
Aster4Note® is a proprietary security feature developed by PWPW (Polska Wytwórnia Papierów Wartościowych S.A.), the Polish Security Printing Works, founded in 1919 and based in Warsaw. It is one of a family of PWPW's own named security features — alongside ChromAngle4Note®, Mirage4Note®, Umbra4Note®, and Zora4Note® — that are offered as proprietary solutions integrated into banknotes, visas, and other secure documents produced at PWPW's facilities.
Technology & Effects
Aster4Note® is an element made of foil or ink with a dynamic optical effect, produced as a result of intaglio embossing. The developed structure creates individual shapes and gives the impression of movement. Pwpw
The technology exploits the interaction between the precision embossing achievable through intaglio printing — in which ink is forced under high pressure into engraved recesses, creating a raised, tactile print with precisely defined three-dimensional micro-structure — and the reflective or optically variable properties of the ink or foil material to which it is applied. The embossed relief structure modulates how light is reflected across the element as the viewing angle changes, creating a perception of movement or depth within the shaped design. This combines two independent security barriers in a single production step: the intaglio embossing itself (which is tactile and requires specialist engraved plates and high-pressure presses) and the optical variability of the resulting embossed element.
The feature is available in both foil and ink variants, giving designers flexibility in its integration — as a standalone optically variable patch or as an ink-based element embedded within the broader printed design of the note.
Security Levels
Aster4Note® operates at Level 1 (public) through its visible dynamic optical effect, which is perceptible to the naked eye under normal lighting when the document is tilted. The tactile raised quality of the intaglio embossing provides an additional immediate feel-based authentication cue. The combination of embossed structure and optically variable material creates a feature that cannot be replicated by scanning, photocopying, offset printing, or standard commercial foil stamping — all of which lack the precision relief geometry produced by the intaglio embossing process.
Form Factors & Application
Aster4Note® is applied during the intaglio printing stage of banknote or secure document production, either as an ink element within the engraved design or as a foil element hot-stamped in register with intaglio embossing. It can be shaped into any design motif — denomination numerals, national symbols, geometric forms — and integrated into the visual architecture of the note rather than appearing as a discrete separate patch.
- Name
- Aster4Note®
- Category
- Security Feature
- Effect Types
- Embossing Foil
- Company
- Linked Features
- 1 security feature