Advancing Low-Friction Sealing with Polymer Brushes

Pursuing higher performance with advanced surface treatment technology. The company’s core sealing products, including oil seals and O-rings, are expected to deliver both airtight performance that prevents leaks and low friction that improves energy efficiency in machinery. These two qualities are often in tension, but NOK continues to refine both through ongoing R&D focused on surface functionality, materials, and component design, centered at its Shonan R&D Center in Fujisawa, Kanagawa. In recent years, this work has expanded to include polymer brushes, a surface treatment technology gaining attention worldwide. Rather than focus solely on short-term gains, NOK is pursuing mid to long-term research to improve the performance of its sealing products.

Differentiation Through In-House Adhesive Development

One of NOK’s signature products, the oil seal, is typically made by combining rubber, a metal ring, and a spring. Adhesives are used to integrate these different materials into a single unit. However, bonding dissimilar materials such as rubber and metal is technically challenging, and oil seals must also perform reliably in demanding environments. For instance, they need to maintain adhesion while exhibiting heat and oil resistance, even at temperatures exceeding 100°C. To meet these stringent specifications, NOK has developed its own in-house adhesives for over 60 years.

End-to-End Development of Precision Plastic Products: ESTOH (Part 2)

Approximately 90% of ESTOH Co., Ltd.'s (Headquarters: Ikuno-ku, Osaka, President: Kenji Nakamura) products are plastic gaskets for automotive lithium-ion batteries (LiBs). One of the company's key goals is to expand its market share in this field by leveraging NOK's marketing strengths to stay aligned with ever-evolving customer needs. At the same time, ESTOH is focused on expanding into new sectors by making full use of its vertically integrated production capabilities for precision plastic components.

End-to-End Development of Precision Plastic Products: ESTOH (Part 1)

ESTOH Co., Ltd. (Headquarters: Ikuno-ku, Osaka, President: Kenji Nakamura), which joined the NOK Group in 2023, has built a strong track record in the production of plastic gaskets used in lithium-ion batteries (LiBs) for electric vehicles (EVs). It handles every step from mold design through to final production. ESTOH’s core strengths include designing and machining ultra-precise molds at the micrometer scale (one-millionth of a meter), advanced injection molding using those molds, and 100% visual inspection for quality control. Now part of the NOK Group, ESTOH is looking to tap into the Group’s R&D and marketing capabilities to unlock even greater synergy.

Evaluating Material Properties in Manufacturing to Enhance Efficiency

To produce oil seals and O-rings, various raw materials are blended to achieve the desired performance and physical properties. While raw materials come with data provided by manufacturers and finished products undergo a thorough evaluation, there is less readily available data on intermediate materials, those still in the processing stage before becoming final products. However, analyzing their properties is crucial for product development and manufacturing processes, as they play a key role in industrial production. For nearly 20 years, NOK has independently measured the processing characteristics of these intermediate materials. By expanding the scope of its evaluations, the company aims to improve production efficiency and strengthen its competitive edge.

Unlocking New Value for Users Via Data Utilization

Over its 84-year history, NOK has accumulated an extensive body of knowledge about materials, product functionality, structural design and production related to its core oil seal business. By digitizing, analyzing and leveraging this data, the company is pursuing initiatives that enhance its operational efficiency and swiftly responding to evolving user needs. A key element in this data utilization is artificial intelligence (AI). NOK collaborates with the data science division of its capital and technology partner, Germany's Freudenberg Group, to pursue various upgrades in efficiency.

Driving Reliability with Lubricants: NOK Klüber

The NOK Group holds the largest domestic market share in oil seals and O-rings, and our products contribute to the stable operation of a diverse range of machines. These include automotive engines, powertrains, hydraulic equipment in construction machinery, and multifunction printers. Beyond our seal technologies, such as those used in oil seals and O-rings, the Group also ensures stable operation by reducing wear on moving parts in machinery through lubricants. NOK Klüber, based in Minato, Tokyo, takes on this essential role.

Differentiation Through Group Strength: Acrylic Polymers as Core Materials

NOK's seal products — including its flagship oil seals — primarily use synthetic rubber, which is a common material in automotive components because of its essential oil and heat resistance. The main element of acrylic rubber is acrylic polymer, which is essential to determining the performance of oil seals and other similar products. Unimatec, a member of the NOK Group based in Minato, Tokyo (led by President Hiroaki Kikuchi), specializes in developing and producing acrylic polymers. As the automotive industry's business environment evolves, Unimatec leverages the Group's strengths to meet diverse needs.

Leveraging Group Strengths to Develop FPC-Based Cell Separation Devices

NOK is set to celebrate its 100th anniversary in 2041. As part of its long-term initiatives, the company has identified wellness-related fields — including life sciences and healthcare — s priority areas for innovation. Within this focus, NOK is striving to commercialize cell separation technology using flexible printed circuits (FPC) — a product line that exemplifies the synergy created through the specialized expertise of its Group companies. FPC are the flagship products of Mektec, a NOK Group company engaged in the manufacture and sales of electronic products. Headquartered in Tokyo's Minato Ward, and known globally as a leading player in the FPC market, Mektec is now advancing research and development to harness the unique advantages FPC bring for cell separation devices.

Making a Hydrogen Society Possible with Rubber Technology

The push to promote hydrogen use is gaining momentum. As carbon neutrality (net zero greenhouse gas emissions) becomes a cucial goal for industries worldwide, hydrogen and ammonia are spotlighted as energy sources that do not emit carbon dioxide (CO2). Ammonia derived from hydrogen further elevates expectations for hydrogen as a next-generation energy source.

NOK Adapts to Automotive Industry Changes with New Technologies

NOK's goal is to achieve consolidated sales of one trillion yen by FY2031, coinciding with its 90th anniversary. The automotive industry is undergoing a once-in-a-century transformation, and as a key supplier to the sector, NOK is evolving to handle these changes.
On May 22, 2024, at the Automotive Engineering Exposition 2024 held at Pacifico Yokohama, NOK showcased cutting-edge products and technologies to address critical societal challenges, including electrification and carbon neutrality (net zero greenhouse gas emissions). Earlier in April, the company introduced a unified corporate identity (CI) for its 92 Group companies worldwide, underscoring its commitment to innovation and collaboration. The exhibition featured standout technologies and products that reflect the Group's combined expertise.

Expanding FPC Applications: Opportunities in Vehicle Electrification

Flexible printed circuits (FPC) are thin and flexible circuit boards that enable the miniaturization of electronic devices and improve component mounting capabilities. Mektec, based in Minato City, Tokyo, and led by President Taro Ito, is part of the NOK Group and plays a key role in its electronic products business. Mektec holds the third-largest global market share in FPC sales. Since it began operations in 1969, Mektec has pioneered the domestic FPC market, leading its growth and development.

Leveraging Material and Design Expertise to Ensure Safety and Reliability in Electric Vehicles

The advent of electric vehicles (xEVs) presents many new challenges, including thermal management and electromagnetic noise. Drawing on its expertise in material formulation and shape design gained while developing seal products, NOK offers a lineup of high-performance products tailored for electric vehicles, including a wide range of components and products to meet customer expectations. Senior Planner Junichi Watanabe and Masahiro Tanioka, manager of the NOK Group R&D Mobility Products Planning Department, shared insights into NOK’s offerings for electric vehicles.

Providing Solutions That Meet Needs Quickly: Leveraging Statistical Methods for Material Formulation

Over the years, NOK has accumulated approximately 88,000 rubber material formulation recipes developed in response to changing needs and demands. Currently, the company leverages this vast dataset of recipes to optimize new material formulations through statistical methods. This approach shortens development time and serves as a powerful tool to quickly respond to needs even amidst rapid environmental changes, such as improving vehicle fuel efficiency and adapting to electrification.

Making the Invisible Visible: Analytical Techniques for Visualization at the Molecular Scale

NOK's strength lies in its technological capability to produce rubber with a wide range of properties that meet various societal needs. At the core of this capability is our advanced analytical technology. By visualizing and understanding rubber structure at a molecular scale, NOK develops safe and reliable products.