Longer service life of coin embossing dies thanks to PVD coating
INORCOAT Germany, with registered office in Ostfildern, Swabia, provides innovative solutions for more efficient and cheaper physical vapour deposition (PVD) processes. PVD can replace the galvanic chromium plating of parts, which is still widespread today. With the compact vacuum valve islands from Bürkert, the manufacturer saves money and can offer previously unknown modularity in its systems.
As a result of the high environmental impact, the galvanic chrome coating will only be permitted in the EU with a special permit from October 2024 onwards. During the chromium plating process, one of the byproducts is the highly toxic chromium(VI) oxide, which has been proven to alter genetic material and promote the emergence of cancer. In contrast, physical vapour deposition (or PVD) is a coating procedure that takes place in a vacuum. An elemental metal, such as chrome, is transformed into a gas phase, which can be deposited on a carrier material as a thin, highly adhesive pure metal or alloy coating. This then avoids toxic intermediate stages.
Coating for coin embossing dies
Experts became aware of the new company when INORCOAT won the state Croatian Mint order for coating the embossing dies as part of the local introduction of the Euro. A real race against time began with the undersigning of the memorandum between Croatia and the European Commission on the beginning of the production of Euro coins in September 2021. Ultimately, 420 million coins had to be minted during 2022 and made available on time. “In the end, we had six months to complete everything,” recalls Romain Waidelich, owner and founder of INORCOAT.
As part of the introduction of the euro, the Croatian Mint minted 420 million coins with PVD-coated dies in just a few months.
Longer service life thanks to PVD technology
In order to increase the service life of embossing dies, they were previously conventionally electroplated with chrome. This meant that a service life of typically 200,000 to 300,000 embossings could be achieved. With the technology and systems from INORCOAT, this could be increased significantly, so the Croatian Mint decided on INORCOAT.
“PVD technology makes it possible to increase the service life of a pair of stamps to an average of 1.5 million embossings. It is also environmentally friendly because no substances harmful to health are released.”
Environmental Sustainability Project Award
In July 2022, the Croatian Mint began with the coating of 1,500 stamping tools. Many more than were ultimately needed: “In the end, they managed with less than a fifth of that, because with our process we were able to achieve a service life of up to 14 million embossings per pair of stamps,” says Waidelich happily and is visibly proud of the result of his work. INORCOAT was also rewarded for this by the International Association of Currency Affairs (IACA): the company received the Award for the best environmental sustainability project for coins in 2022.
From the coin to industrial use
Like the printing of banknotes, the embossing of coins is a very specific niche market. The problems associated with the galvanic coating of embossing tools are well known. However, there is a lack of experience with new processes such as PVD coating. Nevertheless, Waidelich and his team were able to overcome with flying colours the associated uncertainties of state-owned companies regarding security and their concerns due to the lack of notoriety of the still young company. Elsewhere, for example, the Moroccan National Bank was the first bank in the world to make use of INORCOAT’s systems, using them to coat its printing plates.
Wide range of applications for PVD
In the meantime, many other companies have become aware of INORCOAT and are investing in its environmentally friendly coating technology. “There are an incredible number of areas of application in which conventional galvanic chrome plating can be replaced,” explains Waidelich, showing as an example a guitar with its shiny chrome tuners, locks and bridges.
Simplify complex technology
Waidelich’s vision is to simplify the complex PVD process, make it even more commercially attractive and easier to understand for customers. However, initially it was anything but easy. “Two key components are the vacuum technology on the one hand, and the high-precision metering of the reactive gases in the plasma process on the other,” explains Waidelich. The technology for controlling these partial processes reliably is complex. Many of the suppliers to whom he presented his ideas and asked for support declined: too small quantities, too complex, expensive.
Bürkert makes it possible
Waidelich came across Bürkert more by chance; a subcontractor recommended that he get in touch. “I was surprised. Bürkert was immediately interested and offered to develop an individual solution that offered us several advantages – despite the limited number of units that I was able to predict,” recalls the company founder. Bürkert brought together what he would have had to painstakingly assemble himself elsewhere.
“We received a fully assembled, tested unit that combines vacuum technology and gas control. This saves time and money and makes our lives easier.”
Precise control of process gases
A decisive advantage of INORCOAT systems is their flexibility – despite the compact size. They owe this not least to the modularity of the Bürkert valve islands: Each one includes a shut-off valve block and a mass flow meter, which can be connected together into up to 21 controlled sections. “This is unique and offers enormous variability if a customer wants to create a complex coating with a large number of gas points,” says Waidelich, describing the structure. The user therefore has full control of the process because they can individually adjust the process gas depending on the metallic element and exactly where the plasma reacts.
Modular solution reduces complexity and costs
PVD coating systems by INORCOAT are tailored in a modular manner to suit the needs of the individual application. If a single gas point is required in a small system, only one valve island is installed. “This reduces complexity and costs,” says Waidelich. “But the best thing is that all standard systems can later be expanded into individual, customer-specific solutions as required.” INORCOAT’s customers are happy.
Additional information and download: