Precise control of process gases – modular solution reduces complexity and costs

Because 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. By 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.

Experts became aware of the new company when INORCOAT won the state Croatian mint order for coating the die stamps as part of the local introduction of the Euro. A regular 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 stamped and issued on time over the course of 2022. “We had six months left to deal with everything,” recalls Romain Waidelich, owner and founder of INORCOAT.

The Croatian mint embossed over 420 million coins with PVD-coated stamps for the introduction of the Euro in 2023.

To increase the service life of die stamps, they were previously galvanically chromium-plated as a convention. This enabled a service life of typically 200,000 to 300,000 embossments to be achieved. “The PVD technology enables the service life of a pair of stamps to be increased to an average of 1.5 million embossments. This helps protect the environment, as no substances that are harmful to health are released,” says Romain Waidelich of the enormous advantages of the procedure. The Croatian mint therefore decided to invest in the technology and systems by INORCOAT required for the procedure.

In July 2022, the Croatian mint began with the coating of 1500 stamping tools. Far more than were ultimately needed: “In the end, they were able to manage with less than a fifth, because we could sometimes reach service lives of up to 14 million embossments per pair of stamps,” enthuses Waidelich, who is visibly proud of this result of his work. INORCOAT was also rewarded for this by the International Association of Currency Affairs (IACA): the company received the prize for the best environmental sustainability project for coins in 2022.

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. Relatively new procedures, such as PVD coating, lack experience values. However, Waidelich and his team were able to face the state company’s subsequent uncertainties with regards to safety, and its concerns due to the relatively young company’s lack of a reputation, with bravery. 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.

In the meantime, many more companies became aware of INORCOAT and invested in their environmentally friendly coating technology. “There’s an unbelievable amount of areas of application where conventional galvanic chromium plating can be replaced,” explains Waidelich, and shows a guitar as an example, with its gleaming chromium mechanics, locks and bridges.

Waidelich’s vision is to simplify the complex PVD process, make it more commercially attractive and comprehensive for customers. However, this was anything but easy at first. “Two key components are firstly, vacuum technology, and secondly, high-precision dosing of reactive gases in the plasma process,” explains Waidelich. The technology for controlling these partial processes reliably is complex. Many of the subcontractors to which he presented his ideas and asked for support turned him down: too low quantities, too time-consuming, expensive.

Waidelich then fell upon Bürkert by chance, a subcontractor recommended that he make contact. “I was surprised. Bürkert was immediately interested and offered to develop an individual solution that offered us several advantages – despite the only manageable quantity that I could predict,” recalls the company founder. Bürkert brought together something that he had had to assemble by himself elsewhere, with great difficulty: “We received a fully installed, test unit that brings vacuum technology and gas control together,” enthuses Romain Waidelich. “This saves time and money, and makes life easier for us.”

A decisive advantage of INORCOAT systems is their flexibility – despite the compact size. This is all thanks to the modularity of the Bürkert valve islands: each one includes a shut-off valve block and a mass flow meter that can be plugged together in any order on up to 21 control loops. “This is unique and offers incredible variety, in the event that a customer wants to a complex coating with a large number of gas points,” Waidelich says of the structure. The user therefore has full control of the process, as they can then individually set the process gas very precisely and accurately, wherever the plasma reacts, depending on the metallic element.

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 then installed. “This reduces complexity and costs,” states Waidelich. “But the best part is that all standard systems can be upgraded into individual, customer-specific solutions later on, and entirely on demand.” INORCOAT’s customers can’t wait.