The Flood Protection System is an award-winning invention by Kilian Günthner that introduced a passive, self-activating approach to protecting doors and windows from floodwater. Inspired by the absorbent polymers used in diapers, the system uses superabsorbent material that expands on contact with water, sealing gaps automatically without electricity, mechanical deployment, or human intervention. Developed after severe rainfall caused water to enter his family home, the invention turned a practical household problem into a novel product design solution. Major institutions like LANXESS AG, Wallburger GmbH, and the University of Cologne invited Kilian to further develop the project. The project received recognition through Germany’s Jugend forscht competition, earned the Nicolaus August Otto Special Prize for Innovation, was covered by major newspapers, and led to Kilian being invited to sign the Golden Book of the City of Cologne.
Industry Recognition
After the invention was honored with the honorary prize at the Nicolaus August Otto Award for Innovation, chemicals company “Lanxess AG”, window company “Wallburger GmbH”, and patent law firm “Kreisler Selting Werner” (now “dompatent – Partnership of Patent Attorneys and Attorneys at Law mbB”) invited Kilian Günthner to collaborate on further research and development of the prototype to be shipped built into windows:
LANXESS AG is a publicly listed German specialty chemicals company. It is active in 32 countries, employed around 11,800 people in 2024, and reported €6.4 billion in annual sales for that year. The company traces its roots to Bayer’s nineteenth-century industrial history and was established in 2004 through the spin-off of most of Bayer’s chemicals business (Bayer, the German life science company founded in 1863 and best known internationally for its businesses in pharmaceuticals such as Aspirin, consumer health, and agriculture). LANXESS focuses on chemical intermediates, additives, specialty chemicals, and consumer protection products, and it reported in its 2024 Annual Report that its patent portfolio comprised approximately 640 patent families covering around 5,260 property rights as of year-end 2024.
Wallburger GmbH is an established window and door company with a long operating history dating back to 1926 with in-house manufacturing facilites. The company has a specialization in windows, doors, security systems, shading, and related building solutions. Wallburger states that it is among the leading window and door manufacturers in the greater Cologne area. In context, Wallburger is best understood as a longstanding and commercially serious regional company in the building-products sector.
‘Kreisler Selting Werner,’ now operating as ‘dompatent – Partnership of Patent Attorneys and Attorneys at Law mbB,’ is a long-established, award-winning intellectual-property firm. The firm traces its origins to 1947, when it was founded in Cologne as a patent law practice, and today it reports having more than 100 personnel. It has particular strengths in patent prosecution, including work in pharmaceuticals, life sciences, mechanical engineering, and electrical engineering.
Academic Recognition
In addition, Prof. Dr. Dr. h.c. Thomas Krieg, the Vice-Rector for Research and Scientific Talent Development of the University of Cologne, on the Rector’s letterhead, invited Kilian Günthner to collaborate on the further progress of this invention together with Professor Meerholz from the Institute of Physical Chemistry at the Faculty of Mathematics and the Natural Sciences of the University of Cologne. The letter further conveys congratulations of the Rector of the University of Cologne, Prof. Dr. Dr. h.c. Axel Freimuth.
The University of Cologne is a major German public research university and one of Germany’s oldest and most prominent academic institutions. Founded in 1388 and re-established in 1919, it is today one of the largest universities in Europe and describes itself as one of Germany’s leading research universities, with roughly 45,000 to 50,000 students, six faculties, and a wide academic portfolio of approximately 260 to 300 degree programmes. Its research profile is evidenced in particular by its performance in Germany’s Excellence Strategy, under which it has secured five Clusters of Excellence – a nationally significant marker of internationally competitive research.
Prof. Thomas Krieg was a senior research leader at the University of Cologne, serving as Vice-Rector for Research and Scientific Talent Development, a role within the university’s top governing executive body. He also served and serves as a Vice-President of the Leopoldina, Germany’s National Academy of Sciences, which underscores his standing within German science at the national level.
Image: Thomas Krieg | © Michael Wodak / MedizinFotoKöln
Prof. Axel Freimuth is a German physicist who served as Rector of the University of Cologne from 2005 to 2023. In the German system, the Rector is the university’s chief executive and legal representative, broadly comparable in significance to a university president in the United States. Before becoming Rector, Freimuth built a career as a research scientist in experimental solid-state physics. He later served as Dean of the Faculty of Mathematics and Natural Sciences before becoming Rector.
Image: Axel Freimuth | © Raimond Spekking
Press & Media
Kölnische Rundschau (Newspaper)
Flood Protection Using Diaper Technology
Kilian Günthner from Mülheim earned an award for an invention inspired by diapers: he installed superabsorbers on doors that swell and seal gaps automatically when flooding occu...
Express (Newspaper)
Cologne Researcher Detects Explosives
September 2007: heavy rain; water runs under the front door and into the hallway. Kilian Günthner reached for a baby diaper and sealed the door with it. That was the beginning o...
Köln Nachrichten - Das Online-Nachrichtenmagazin für Köln
Sixth Innovation Award of the City of Cologne Goes to Cancer Research
Kilian Günther received a special award for his flood protection invention. Cologne law firm Kreisler Selting Werner presented the young inventor with a check for...
Kölnische Rundschau (Newspaper)
Kilian Tackles Flooding with Diapers
Kilian Günthner focused on flood protection in the “Technology” category. His idea came after the September floods that left large parts of Bad Münstereifel under water. In man...
Kölner Stadt-Anzeiger
A Prize for Cologne Minds
Kilian Günthner developed a flood protection device that can be installed in doors and windows. When water flows in, a “super-absorber” automatically seals everything...
Kölnische Rundschau (Newspaper)
Bad Münstereifel: Kilian's “Diaper Patent” Wins Award
The best young researchers in North Rhine-Westphalia recently competed in Bochum at the junior division of Jugend forscht, Germany’s national science competition, known as Stude...
Stadt Köln - Amt für Presse- und Öffentlichkeitsarbeit
Lord Mayor Schramma Presented the Nicolaus August Otto Prize of the City of Cologne for Innovation
The invention allows doors and windows to be made flood-resistant in an environmentally friendly manner, with low effort and low cost, using so-called superabsorbers, a fleece m...
Kölner Stadt-Anzeiger
With Diapers, Kilian Made It Onto the Winners' Podium
Kilian Günthner from St. Michael Gymnasium made it onto the winners' podium when the best young researchers...
