Toyota Auto Body : Kyowa Interface Science

Toyota Auto Body Co., Ltd., as a complete vehicle manufacturer within the Toyota Group, handles everything from planning to production for models such as the Alphard, Noah, Hiace, and Land Cruiser. Mr. Furui, who is in charge of cold-weather usage environments in the Vehicle Testing Department, wanted to "quantify" a particular winter phenomenon.

The company has both simple testing equipment and considerable experience. So why did Mr. Furui seek out an external measurement service and commission Kyowa Interface Science Co., Ltd.? And what were the results of that choice?

Melting snow prevents doors from opening

――― Please tell us the background that led to the need for this measurement.

Mr. Furui: In winter, the snow accumulated on the roof of a car melts depending on the weather, which is a mix of sunny and snowy. As this melted snow slowly flows from the top to the bottom of the vehicle, the temperature can drop again, potentially freezing. When this happens, in some cases, the doors may become stuck, or the retractable steps equipped on electric sliding doors, like those on the Alphard and Noah, may stop working, negatively impacting customer usability. Our job is to better understand the phenomenon and use that information in development to prevent such situations from occurring.

While we had some empirical understanding of these phenomena, we wanted to understand them in detail, as early as possible in the development process, including where and how the snowmelt water flows and where the risk of freezing increases. The flow pattern varies with the material and part shape, making it very difficult to predict in advance.

Therefore, we began considering this measurement to confirm how the water slides down through experiments and to organize the data numerically, which would lead to a more reliable evaluation.

Seeking Validity: Why Internal Testing Wasn't Enough

▲ Vehicle testing in progress (Source: Toyota Auto Body website)

――― You mentioned that you had conducted simple tests in-house, but why did you decide to outsource it?

Mr. Furui: We had a concrete understanding of what was needed and what conditions were required in-house, and we had been conducting some simple tests for some time. However, since we are not interface experts like Kyowa Interface Science, our motivation stemmed from a desire to verify whether the values ​​we obtained were truly reasonable. Therefore, from the beginning, we sought a measurement service provided by experts that could verify our findings using reliable equipment and measurement methods.

Track Record, Internal Evaluation, and Dialogue — Choosing an Expert

――― Please tell us about the process of choosing Kyowa Interface Science.

Mr. Furui: Looking at their website, I got the impression that their products are used in a variety of industries, including food companies, soap companies, the automotive industry, and the construction industry. After researching their domestic track record and market share, I determined that they had a wealth of experience and could meet the needs of a wide range of industries. When I asked our internal materials technology department, I heard that they were actually using Kyowa's measuring instruments. After contacting them and speaking with them, I felt confident entrusting the project to them based on their technical explanations and courteous service.

The "Genchi Genbutsu" Approach to the Showroom

――― You actually visited their showroom in Niiza, correct? It was a paid visit, but what made you decide to go?

Mr. Furui: I prioritized on-site verification. To be honest, I wanted to see the work of interface professionals. What we value at our company is the "Go and see for yourself" culture ― going to the actual location, touching the product, and proceeding only after being convinced. Therefore, I thought that by speaking with them directly and seeing the equipment and measurement process, I could make an informed decision before making a request.

▲ Kyowa Interface Science Showroom at Niiza Headquarters

▲ Kyowa Heritage Entrance Display at Niiza Headquarters

When we actually visited the measurement site, what surprised us most was the staff's depth of knowledge and dedication to quantification. The technique of capturing the moment of movement after droplet deposition and the management of the measurement environment were on a completely different level from what we had been doing in-house. We became even more convinced that they would take our challenges seriously.

Confidence in Development

――― How were the measurement results?

Mr. Furui: This measurement confirmed that the simple measurements we had accumulated so far largely matched Kyowa Interface Science's precise measurements. This is a very significant achievement. Having received confirmation from a professional perspective that "our direction is correct" has allowed us to proceed with the next development steps with confidence. We were very impressed by how they translated the difficult-to-see phenomena into easily understandable numerical values and made them visible.

――― It seems that not only the measurement results report, but also the subsequent dialogue were important.

Mr. Hashizume: The technical discussions with the person in charge of the measurements were a very valuable experience for us. Instead of just looking at the numbers, they explained "why this behavior occurs" from a specialized perspective in interface science, which further broadened our knowledge. Rather than concluding with a single outcome, they raised new questions, such as "What about under these conditions?" which prompted us to request additional measurements. We appreciated their flexibility in meeting our needs, which made us see them not just as an outsourcing provider but as a true partner working with us to address the issue.

Towards the next challenge, anticipating even harsher environments

▲ Mr. Furui, Mr. Hashizume, and Mr. Ishii from Toyota Auto Body

――― Please tell us about your future prospects.

Mr. Furui: In the future, we would like to challenge ourselves to investigate not only the behavior of water droplets in low-temperature environments but also in harsher conditions closer to actual environments, such as slushy snow or more complex multiphase states. We intend to accelerate our research and development by utilizing the knowledge about interfaces gained from this initiative to deliver even greater peace of mind and safety to our customers. We look forward to receiving advice and support from Kyowa Interface Science, leveraging their expertise.