Does Polymer Technology Make Plastic Banknotes Counterfeit-Proof?

Polymer notes are made of different polymer materials, mainly polypropylene. They were first released in 1988 by the Reserve Bank of Australia, which was the first country to introduce plastic banknotes. The earliest plastic banknote was a A$10 note, created in commemoration of Australia’s 200 year anniversary. Plastic currency is being fast adopted by many countries because of the enhanced security features that it offers and its increased durability. Countries such as Vietnam, Canada, Israel, and Romania have fully adopted polymer notes due to the variety of benefits that they offer. Polymer banknotes are easily identified by their clear, plastic window and diffraction grating. A blend of cotton and polymer banknotes are known as hybrids and make up the majority of polymer notes in circulation worldwide.

The adoption of polymer notes has also spurred the development of a bill counting machine designed to efficiently handle and authenticate these durable banknotes.

The science behind polymer money technology

The evolution of polymer technology has seen the use of polymer in a variety of everyday objects, including packaging materials, decorations, and car parts. The polymer substrate used in plastic currency is derived from special polypropylene material. Highly specialized technology is needed to produce this material and it cannot be found commercially. The substrate is made up of multiple layers that are formed using a bubbling process. This involves transparent plastic beads being melted down and blown into a sizable bubble. While this occurs, the film is stretched in several directions to position the polymer molecules.

The walls are then pinned together and cooled, creating a transparent polymer film that has become a characteristic of plastic banknotes. This film is biaxially oriented polypropylene (BOPP) and holds up well when being stretched. A polymer varnish is also applied to reduce the plastic feel of the note.

The pros and cons of polymer banknotes

As previously mentioned, the durability and difficulty of counterfeiting polymer notes have resulted in them being used in a variety of countries and praised for their innovativeness. However, they are not without faults. Below is a list of pros and cons that come with this innovative currency material:

Pros

1. Durable - they are far more long-lasting than paper money. It is believed that they can last two-and-a-half times longer than paper banknotes.
2. Difficult to counterfeit - intricate images and the use of sophisticated technology, described above, make it very hard to replicate polymer bills. Countries that use plastic currency have reported a noticeable decrease in counterfeiting attempts by fraudsters.
3. Hygienic - Unlike paper money, which easily attracts fecal matter, dirt, and dust, polymer banknotes accumulate dirt far less quickly. Polymer is a less hospitable surface for bacteria and germs to thrive, and is easier to clean without damaging the integrity of the note.
4. Resistant to extreme temperatures - Polymer bills can withstand extreme temperatures, both hot and cold. It is believed that polymer notes can weather temperatures up to 140 degrees Celsius.
5. Environmentally-friendly - Once the banknote has been sufficiently worn out, it can be recycled. Polymer notes are also less resource-intensive than paper notes. 75% of US paper notes are made of cotton and require large amounts of water and pesticides to make.

Cons

1. Incompatibility - Older money counting machines may not be able to sort plastic notes as fast as they can sort paper ones. For this problem to be fixed, older machines may need to be modified or replaced.
2. Color deterioration - The color of polymer banknotes has been known to fade over time. This occurred in Nigeria, where the country reverted to using paper money after their banknotes began to fade and started to be rejected by business owners.
3. Easy to crease - The composition of polymer notes make them difficult to fold and leaves creases behind.
4. Reaction to moisture - Polymer notes do not react well when they come into contact with water, which leaves the note sticky to the touch. This makes it difficult if you are trying to sort the notes or count them using a money counter. Countries with warm and humid climates have reported problems with polymer banknotes for this very reason.

Detecting counterfeit polymer notes

It was believed until very recently that polymer notes could not be counterfeited. However, this is no longer true. A Romanian man was arrested in June 2020, while in possession of fake polymer notes. His forgeries were of spectacular quality and made it impossible for people to differentiate counterfeit banknotes from real ones. This discovery has made him the most prolific forger in Romanian history and cemented his position as the best polymer banknote counterfeiter that the world has yet seen. He is not the first counterfeiter known to make counterfeit banknotes , of course.

There are a variety of new technologies that can determine whether or not a note is fake. The visual and tactile inspection can also be used if these technologies are not readily available. Below are some tips on how you can define counterfeit notes:

1. Notice the feel - As shown above, polymer notes are made from a polymer substrate that gives the notes a unique feel that is not easy to replicate. If crumpled up, genuine polymer notes should revert to their original shape.
2. Analyze the window - A distinctive plastic window runs from the top to the bottom of a section of a polymer note. The window should be built into the note and none of its security features should be easy to erase.
3. Inspect the image - A 3D image should be visible, surrounded by a colorful border. The image can be either elevated or sunken.
4. Feel the print - the raised texture of the numbers and portraits on the note can be felt by running your fingers lightly across its surface.
5. Consider the background print - The note is crisscrossed by a variety of lines going in multiple directions and many different colors. These lines are very well-defined. Fake bills might have lines that are not as defined, different thicknesses, and different colors. 
6. Notice the microprint - There are many parts of the note which will be covered in tiny, yet distinctive, text.
7. Use a suitable UV light - Certain security features on Austalia’s polymer notes, such as the image of a bird, serial number, and year of print will turn fluorescent when placed under a UV light with a wavelength that is centered around 365nm. The chemistry behind counterfeit money cannot match that which is used when creating real banknotes. The element europium and other lanthanides are found in banknotes and create the fluorescent effect when a UV light is shone onto the note. It is highly doubtful that counterfeiters will be able to access, let alone use, these rare elements.
8. Use a specialized money detector machine - a polymer counterfeit money detector requires unique antistatic rollers to accurately work with polymer notes. These banknotes can have static electricity problems, particularly in countries with more arid climates, causing the notes to stick together, increasing the chance of counting inaccuracies. The static can cause notes to “float” resulting in them not landing properly at the end of the stacker. Specialized counterfeit money detectors and money counting machines tackle this problem using anti-static stacker wheels, shock-resistant components, and brushes to ensure that no static is created by the polymer notes.

Conclusion

The benefits of using plastic currency far outweigh the negatives. However, as recent events have shown, polymer banknotes are not immune to forgery, no matter how strong their security features are. Although they are not perfect, it is hard to deny their durability, low carbon footprint, and cleanliness compared to conventional paper banknotes that are still used in the majority of countries around the world. Although there are difficulties that can arise, depending on which country and climate polymer notes are introduced to, there is no doubt that plastic is the currency material of the future.