The rock in the surf

Dr.-Ing. Max Schlötter GmbH & Co. KG from Geislingen an der Steige is a heavyweight in the German electroplating and surface technology sector. Its business model is based on the development and sale of modern electrolytes and the associated plant technology. While Germany and the world are characterized by far-reaching upheavals in industry and the economy, the 112-year-old medium-sized company is building on stable values and sustainable research and development.

Visits to suppliers in the electroplating industry are sometimes very productive. This is also the case at Schlötter: the electrolyte manufacturer's interfaces range from the largest to the smallest companies in the industry. Almost every electroplating company has already purchased products from Schlötter: in the form of specialty chemicals used to mix the electrolyte or as a finished electrolyte in a hazardous goods container. Others know the company as a plant manufacturer. The Geislingen-based company therefore has its finger on the pulse of the industry with insights into changing demand and emerging trends. Schlötter itself is a kind of rock in the surf, maintaining continuity and providing stability with its range of products and experience.

At the heart of research

On-site visit in Geislingen an der Steige with CEOs Dr. Stefanie Geldbach and Dr. Michael Zöllinger as well as COO Thomas Haberfellner. It quickly becomes clear that research has been at the heart of the company since chemical engineer Dr. Max Schlötter founded it in Leipzig in the final years of the German Empire. Today, electroplating technicians, chemical engineers, chemical laboratory technicians and materials scientists work on solutions to problems or new developments for the industry in a dedicated research building, divided into electrolyte development and service and analysis laboratories. The research building is in a wonderful location: From the second floor of the 1968 building with its 2,500 square meters of space, the view from the large windows extends far up to the wooded hills around Geislingen, on which castle ruins and wind turbines are enthroned.

In the physics laboratory, Dr. Felix Goll stands at a cutting machine for printed circuit boards. Surrounding him are X-ray, digital and analog microscopes for the most precise examination of surfaces. Dr. Goll cuts a part from a larger copper-plated plate, which is later embedded in epoxy resin and analyzed under the microscope. The aim is to precisely measure the blind holes in the circuit board in order to optimize its coating. There is also a brand new microscope here that enables nanometer-precise 3D analyses. This means that electrolytes can be developed on an even more sound basis.

We continue to the chromatography laboratory for the analysis of customer samples sent in - 20,000 a year, on which around 100,000 parameters are analyzed. Methods include capillary electrophoresis, spectroscopy and four machines for high-performance liquid chromatography (HPLC). For example, the longevity of coatings is determined by the respective electrolyte. It is then often checked whether additional concentrations are required, for example.

The quality and service laboratory scrutinizes all incoming and outgoing raw materials. The key piece of equipment here is the titrator, which can take more than 200 samples and analyze them for their metal content and other properties. Other analysis devices determine the main and foreign metal content. Numerous vessels with electrolytes and pre- and post-treatments are placed on the laboratory benches alongside electrical equipment and analysis technology of all kinds. In addition to checking incoming and outgoing raw materials and products, the chemists and electroplating technicians also work on solutions to problems such as the insufficient gloss of components after coating. In the event of such defects, the Geislingen team tests the electrolyte and then advises companies on the basis of their findings. In this case, the recommendation is to add a brightener. The analyses take an average of two days, as electroplating technician and service manager Christian Mösle explains - this is when the electroplating company usually receives its results.

Trends: betting on the future

Dr. Felix Goll at a cutting machine for printed circuit boards. His analysis is used to measure blind holes in order to optimize the coatingTrend researchand new developments take place in Development, where Dr. Nils Ulrich is currently working in a white lab coat. He is working on a small test electrolyzer. Surprisingly, not only the cathode, anode and bipolar plates are electroplated in the electrolyser, but also the stainless steel tiles for gas removal. Ulrich is currently working with a proton exchange membrane (PEM) electrolyzer, but Schlötter is also working on alkaline (AEL) and anion exchange membrane (AEM) electrolysis. Together with other partners, the company is involved in the German government's AEM direct project H2 GIGA. The focus here is on AEM electrolysis. "This is one of the very important projects for the future," emphasizes Dr. Zöllinger. He hopes that electrolysis will one day take place in Germany - but he lacks faith in view of missed opportunities in the past, such as the failure to establish a solar industry.

Germany was and is a leader in expertise for today's photovoltaics. However, an industry was built up in China, which led to the well-known dependencies on the Middle Kingdom. "If we can supply the chemistry and the systems, that's fine for us," says Dr. Zöllinger, lowering his expectations. Dr. Ulrich has now placed a stack of several electrolysis cells on the lab bench. A rectangular metallic structure that is held together by screws and rivets. "The coating plays a huge role in the efficiency of the electrolyser," he says. And his research work is paying off. The current experiment was able to reduce the voltage during water splitting by 20 percent, which reduces costs and increases hydrogen production. There are many things to consider when it comes to electrolysis. PEM electrolysis, for example, takes place in an acidic environment, which is why corrosion stability plays a major role. However, this is not currently leading to the increased use of galvanic protective coatings, but to the use of corrosion-resistant metals such as titanium. This is because coatings with high corrosion protection are often passive, i.e. they do not conduct - but this is a disadvantage in electrolysers. "Building an electrolyser is not rocket science," says Dr. Zöllinger. The technology is older and the surfaces are reasonably well known. "The devil is in the detail," says the manager. "The real challenge here is to introduce more efficient material systems."

From beaker to practical test

No crop circles from supposed aliens, but a three-dimensional image of a surface using a confocal microscope. This significantly improves electrolyte developmentOncea promising development has been successfully completed in the beaker, the paint sample test is carried out in the new electroplating center, which was inaugurated in 2017. 80 baths are lined up close together with a total of 400 liters of electrolyte ranging from copper and zinc to electroless nickel and silver to passivations, sealants, chromium(III) and much more. A vibrator can be heard further back in the circuit board area - a penetrating noise similar to that of a percussion drill. Its purpose is to remove air bubbles from the fine holes in the PCB so that the metallization is successful. Rooms lead off from the well-equipped "bath landscape". These include the rack workshop, where, depending on the coating requirements, e.g. masking, the appropriate rack with hooks is produced. In other rooms there are blasting cabins for processing surface mechanics or grinding and polishing machines.

All the processes used by the Geislingen electroplating experts can be displayed here. If the practical tests of new processes meet expectations, large-scale production follows either in Geislingen or at the production site in Ireland. All types of corrosion tests are also possible in the technical center. In order to fully exploit the available technical possibilities, the company also works closely with the Research Institute for Precious Metals and Metal Chemistry (fem) in Schwäbisch Gmünd as well as Aalen University and the University of Ulm. There is only one sector in which the technical center is not so well versed: jewelry, for example gold plating. However, Schlötter already has good expertise in technical gold, which is required for conductive surfaces in the printed circuit board sector, for example.

The technical center is also essential for training. Schlötter currently employs 16 trainees, ten of whom are new, many of whom come and go from the technical center, as do dual students and compulsory interns. The trainees also learn grinding, brushing and polishing here, "to develop a relationship with the material", as Thomas Haberfellner explains.

Speaking of relationship: during the tour of the technical center, Haberfellner reminds us once again how thin electroplated layers actually are - compared to the 80 to 120 µm that correspond to the diameter of a hair, copper layers are only 20 µm thick and chrome layers as thin as 0.3 µm.

Electroplating technology on the test bench

The hosts Dr. Geldbach, Dr. Zöllinger and Haberfellner are particularly proud of a newly developed test bench for tribology, which is unique in this form. In response to the increasing importance of so-called contact surfaces, i.e. functionalized galvanic coatings, the Schlötter plant engineers, together with iChemAnalytics GmbH, have developed a system which, with its four workpiece holders behind the viewing window, is somewhat reminiscent of an oversized fully automatic coffee machine. Pascal Grimm is carrying out a friction coefficient test here, comparing hard silver and silver graphite. Samples are clamped onto tiny tables. When the system starts, the tables with the coated samples move back and forth continuously. An object suspended above them then removes the coating. In this way, 10,000 cycles can be simulated in one night. The system can generate a temperature of 15 to 40 degrees and a nitrogen atmosphere in its interior and monitor measurements live - system technology at its best. The result of the comparison: silver graphite has a higher frictional resistance, at least in the coating variant tested here.

Triad of reliability, service and research

The influential banker Alfred Herrhausen - who became sadly famous when he was murdered in an RAF bomb attack - was regarded as the spokesman for "Deutschland AG" in the 1980s. He once said: "You can only sell products in the long term if you have a good reputation. Schlötter's top management is also convinced of this and is now available to answer questions in a meeting room after the tour. During the conversation, words such as "partnership-based cooperation at eye level" and "support with broad basic knowledge at the cutting edge of technology" are used in connection with customer care. The traditional medium-sized company relies on the triad of reliability, service and research when it comes to customer relations. "The market is currently in such a state of flux that service is very important," says former Head of Service Haberfellner. The three hosts agree that this is why Schlötter will continue to provide good service in the future. Decades of experience are an asset that the company's management will continue to throw into the ring in the future. "Nothing can replace experience but more experience," says Dr. Zöllinger. At the same time, Schlötter ensures delivery reliability by maintaining a high level of stock. Here, too, the company deviates from general market practice, which is characterized by reducing stock levels. And research? This has always been a priority, as demonstrated not only by the modern laboratories and the technical center. Around 20 percent of employees in Geislingen work in research and development.

A world in disarray

Mini PEM electrolyzer. Developer Dr. Nils Ulrich describes the research work. In his experiments, hydrogen production was increasedThebusiness of the medium-sized family company now extends beyond Germany. Over the decades, Schlötter has built up a network of locations from Ireland and England to Sweden, Singapore and China. Recently, Taiwan was added with ten employees. Production only takes place in Europe, but the supply chains have held up despite the various market disruptions of recent years. "We have never reached a point where we were unable to deliver," says Dr. Zöllinger with pride. However, the parameters are now shifting on the global markets. Until now, the REACH chemicals regulation has surprisingly played a positive role by protecting Schlötter in Europe with its high requirements from less regulated competition from abroad. "However, this has now been recognized there," reveals Dr. Zöllinger and adds: "Very similar systems are now being set up in China and Turkey, for example." As a result, the trade advantage in Europe is dwindling, while business outside the EU is becoming more difficult - "especially for a comparatively small company like us", as Dr. Zöllinger points out.

In order to comply with the respective legal requirements, a lot is done in-house and the focus is on product safety and transportation. The focus of foreign activities is on Europe and Asia. Initial feelers are currently also being sent out to the United States. China, on the other hand - previously a market with very high demand for Schlötter with two locations, but also with great, constantly growing competition - is losing its appeal, while South East Asia is becoming more attractive. Schlötter is responding to this by stepping up its service efforts in the region. "Asia is really essential for us," says Thomas Haberfellner, explaining the efforts. In order to be able to serve its global activities, the company has an average of 1200 tons of raw materials and finished products available at all times. In times of just-in-time production, this is actually an anachronism, "which would make any controller throw up their hands in disbelief at the amount of capital tied up in products," as Dr. Zöllinger admits. But unlike a corporation, a family business plans for generations. This requires consistency and tradition, but without sacrificing innovation and flexibility, as he emphasizes.

Regulation: millstone of the medium-sized economy

This stainless steel tile for transporting gas in the electrolyzer is also given an electroplated coatingInnovationand adaptability are not so easy to maintain in Germany in the 1920s of the 21st century. The country is currently characterized by the onset of recession, high energy costs and excessive regulation. Whether it's sustainability, cyber security, supply chains or critical raw materials - the reporting requirements have tripled or quadrupled, as Dr. Stefanie Geldbach describes. She points out that the ever-increasing administrative workload requires the deployment of highly qualified staff, which brings no return. In medium-sized companies like Schlötter, this is perceived as a distortion of competition. After all, non-European competitors do not have to comply with these reporting obligations. And the associated costs cannot be paid out of petty cash. Six employees are needed at Schlötter alone to fulfill the various compliance rules, three of whom have a doctorate in chemistry. "When I started here, it was an employee with a 70 percent job who did this alongside her assistant to the Head of Research and Development," says Thomas Haberfellner, drawing a comparison from the early days of his 38 years at the company. It is also bitter that large companies are happy to pass on their reporting obligations to their medium-sized customers. "If everyone does that, we'll soon need two more people," Haberfellner predicts. All in all: a huge burden for SMEs that drives up costs for entrepreneurs. However, there is no reason for hysteria, says Dr. Zöllinger, referring to the many crises Schlötter has overcome over the decades. "We shouldn't say that everything here will go down the drain tomorrow, because it won't. " However, he admits that many companies in the industry are much more vulnerable than Schlötter. Penalties or "bad press" can quickly threaten a company's existence - and the need for advice from the electroplating experts in Geislingen is correspondingly high.

Functional electroplating technology on the upswing

A survey of industry demand in autumn 2024 reveals nothing fundamentally new: zinc-nickel has established itself over the years in the automotive industry as part of cathodic corrosion protection. This is mainly about additional functionalities, such as sealants, other passivations and colors, Haberfellner lists. Sealing with friction coefficients can be used to adjust screw-in values, hot release behavior and contact resistances. As high-strength lightweight components are predominantly used in the automotive sector today in order to reduce the weight of vehicles and thus their energy consumption, hydrogen embrittlement is also playing an increasingly important role here. Schlötter has been responding to this development for several years. A new test bench can now determine material damage caused by hydrogen in two minutes instead of around 144 hours as was previously the case. This is a huge leap in development, which is helping to create new pickling inhibitors that reduce the risk of hydrogen embrittlement. In addition, tin and tin alloys as well as silver graphite coatings, also for high-temperature applications, are particularly popular for functional surfaces. In general, functional surfaces are much more in focus today than in the past. Decorative surfaces such as bright tin-plated surfaces in the household appliance sector and bright silver-plated cutlery, on the other hand, have long been passé, and the POP (plating on plastics) sector is also losing market share. The metallization of 3D-printed components is becoming increasingly important (see also the focus article by Wolfgang Hansal in this issue), to which Schlötter is responding with various new processes.

The challenge of plant engineering

Pascal Grimm at the tribology test bench. The focus of the current test: the durability of contact layersAnothermainstay of Schlötter's business is plant engineering for electroplating. This accounts for around 10 percent of sales. In future, Schlötter Sweden will take over the complete production of the systems. There are cycle-controlled and free-running or programmable systems. In cycle-controlled systems, one product carrier enters while another comes out, which ensures efficient, clear production. Free-running systems, on the other hand, allow the operator to store numerous different products with completely different layer combinations and pre- and post-treatments - "the system control then optimizes the processes," explains Dr. Zöllinger. Great flexibility and mixed operation are possible here. But where is modern plant control systems heading in view of the emergence of new technologies such as augmented reality, predictive maintenance or scrap reduction using machine learning and artificial intelligence? This has not yet been conclusively clarified, admits Dr. Zöllinger. However, the strategic and technological direction should be clear by the end of the year.

Global player with a firm footing

Just as important as setting the course in this area is to follow and help shape the path of business and industry towards climate neutrality. At the request of customers, software was developed some time ago that displays and documents the_{CO2 footprint} of products. These programs were very well received at the important TPCA PCB show in Taipei last year.

In principle, the Geislingen-based company has set itself the goal of achieving climate neutrality by 2032, as well as the greatest possible independence in the supply of chemicals and other raw materials. Looking to the future, the recycling of transport containers and metals from electroplating baths also plays a role in sustainability. As Thomas Haberfellner notes, the former model pupil Germany is no longer alone when it comes to high environmental standards and the sustainable use of chemicals: countries such as Italy, China and the USA are increasingly catching up.

The world is on the move - and right in the middle of it is the medium-sized company Schlötter, on whose continued success around 1000 people and more depend directly. Partner Dr. Stefanie Geldbach represents the family on the management board together with her brother Dr. Tilmann Geldbach. She relies on a modest demeanor and the most personal contact possible with employees, the "charm of a family business", as she says. Despite all the international ties and economic turbulence, Schlötter has kept its feet on the ground. A recipe for success that has now proven itself for 112 years.

Photos: Robert Piterek