Due to the environmental impact, electroplated chrome coating has only been permitted in the EU with a special permit since October 2024. Physical vapor deposition (PVD), on the other hand, avoids such toxic intermediate stages. Inor PCT Deutschland GmbH, known under the brand name Inorcoat Deutschland, based in Ostfildern, supplies PVD systems and also offers coating services using this process, according to the manufacturer of vacuum valve terminals Bürkert GmbH & Co KG, Ingelfingen.
Croatian mint impressed by new process
The company came to the attention of experts when Inorcoat won the contract from the Croatian State Mint to coat the embossing dies as part of the introduction of the euro there. The signing of the Memorandum of Understanding between Croatia and the European Commission on the start of euro coin production in September 2021 marked the beginning of a veritable race against time. After all, 420 million coins had to be minted in the course of 2022 and made available on time. "In the end, we had six months to get everything done," recalls Romain Waidelich, owner and founder of Inorcoat.
To increase the service life of embossing dies, they had previously been conventionally electroplated with chrome. This made it possible to achieve a service life of typically 200,000 to 300,000 embossings. With the processes and systems from Inorcoat, this could be significantly increased, which is why the Croatian Mint opted for the supplier from Ostfildern.
Service life increases drastically thanks to PVD coating
In July 2022, the Croatian mint began coating 1,500 stamping tools. Many more than were ultimately needed: "In the end, they managed with less than a fifth of that, as our process enabled us to achieve service lives of up to 14 million stamps per pair of dies in some cases," says Waidelich happily. 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.
Like the printing of banknotes, the minting of coins is a very specialized niche market. They are aware of the problems associated with the electroplating of minting tools. However, there is a lack of experience with new processes such as PVD coating. Waidelich and his team were nevertheless able to counter the associated uncertainties of state-owned companies regarding safety and their concerns due to the lack of awareness of the still young company. The Moroccan National Bank, for example, is the first bank in the world to use Inorcoat systems to coat its printing plates.
Further areas of application for PVD instead of chrome plating
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 electroplated chrome plating can be replaced," explains Waidelich, showing a guitar with its shiny chrome mechanisms, locks and bridges as an example.
Waidelich's vision is to simplify the PVD process, make it more commercially attractive and easier for customers to understand. However, this was anything but easy in the beginning. "Two key components are 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 required to reliably control these sub-processes is complex. Many of the suppliers to whom he presented his ideas and asked for support turned him down: too small quantities, too complex, expensive.
Supplier makes modular systems simple
Waidelich then 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 a customized solution that offered us many advantages - despite the limited number of units that I could forecast," recalls the company founder. Bürkert brought together what he would have had to laboriously assemble himself elsewhere.
A decisive advantage of the Inorcoat systems is their flexibility - despite their compact size, according to the Ingelfingen-based valve specialist. This is due not least to the modularity of the Bürkert valve terminals: each one comprises a shut-off valve block and a mass flow meter, which can be plugged together to form up to 21 control sections. "This offers enormous variability if a customer wants to implement a complex coating with a large number of gas points," says Waidelich, describing the design. This gives the user full control over the process, as they can adjust the process gas very precisely depending on the metallic element and exactly where the plasma reacts.
Inorcoat builds its PVD coating systems on a modular basis, adapted to the needs of the individual application. If a single gas point is required in a small system, only one valve terminal 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 benefit accordingly.