Quick questions on Polymer banknotes: HSC Investigating Science Module 6

Polymer banknotes carry multiple anti-counterfeiting features layered together.

A clear region in the note that paper cannot reproduce. The window often contains a holographic foil image or printed micro-detail.

Text printed at scales below the resolution of consumer scanners and printers (about 0.2 mm or smaller).

Raised marks felt by visually impaired users; on the current series, these encode the denomination.

Ink that changes colour depending on viewing angle.

Patterns invisible in ordinary light but visible under UV.

Engraved-plate printing creates raised ink relief that can be felt and that resists reproduction.

Microscopic patterns that scanners reproduce poorly.

Polymer notes last three to four times longer than paper. The Reserve Bank reports that polymer note lifespan is approximately five years compared with under two years for paper.

Initial production is more expensive per note, but the longer lifespan reduces total cost.

Polymer notes are 100 per cent recyclable. At end of life they are shredded and remoulded into plastic products like garden furniture or composite building materials.

Explain how biaxial orientation of polypropylene improves the mechanical properties of banknote substrate. [3 marks]

The RBA reports counterfeit rates of approximately 25 parts per million for polymer notes. A media article claims polymer notes are "essentially counterfeit-proof." Evaluate this claim using the data.

A central bank in another country considers adopting Australian polymer technology. (a) Identify one primary data source the bank could use. (b) Identify one secondary source.