Tokyo Ohka Kogyo (TOK)
A Japanese specialty-chemical company focused on semiconductor photoresists, high-purity chemicals and manufacturing materials for advanced lithography.
Company Snapshot
- Founded
- 1940
- Headquarters
- 150 Nakamaruko, Nakahara-ku, Kawasaki-shi, Kanagawa 211-0012, Japan
- Capital
- ¥14.640448 billion
- Latest net sales
- ¥237.029 billionYear ended December 2025, consolidated net sales
- Primary focus
- Semiconductor lithography materials
- Value-chain position
- Specialty semiconductor materials manufacturer
Head Office
150 Nakamaruko, Nakahara-ku, Kawasaki-shi, Kanagawa 211-0012, Japan
Manufacturing Sites
- Kanagawa — Samukawa Town (TOK Technology and Innovation Center and Sagami Plant)
- Fukushima — Koriyama City (Koriyama Plant)
- Tochigi — Utsunomiya City (Utsunomiya Plant)
- Shizuoka — Gotemba City (Gotemba Plant)
- Kumamoto — Aso City (Aso Plant)
- Kumamoto — Kikuchi area (Aso Kumamoto Site)
Company Overview
Tokyo Ohka Kogyo, widely known as TOK, manufactures photoresists and high-purity chemicals used in semiconductor and display fabrication. Its products support multiple lithography generations and adjacent processes requiring precise chemical purity and stable performance.
TOK operates research and manufacturing sites across Japan and a global network close to major semiconductor customers. The company has expanded capacity in Kumamoto and continues to invest in Koriyama and other production locations.
TOK's value is created through chemistry that must perform consistently inside a customer's complete patterning flow. The company's position depends not only on resist formulations but also on purification, quality control, application support and trusted local supply.
Technology & Products
Semiconductor photoresists
Resists for advanced and mature lithography processes.
High-purity chemicals
Developers, removers and related process chemicals.
EUV-related materials
Materials developed for leading-edge patterning requirements.
Packaging materials
Specialty materials for advanced semiconductor integration.
Display materials
Photosensitive and process materials for displays.
Application support
Customer process evaluation and materials optimization.
Position in the Supply Chain
TOK supplies consumable materials used repeatedly in wafer patterning. Its products connect chemical production with coat-and-develop tools, exposure systems, masks, etch and customer process control.
Strategic Position
TOK is expanding global and domestic capacity while increasing R&D for advanced resists and high-purity chemicals. The Aso Kumamoto Site strengthens supply near the Kyushu semiconductor cluster.
Ecosystem Impact
The company links Japanese chemical technology to fabs worldwide and supports domestic clusters in Kanto, Tohoku and Kyushu. Its local production can improve resilience for JASM and other Japanese fabs.
Outlook
Growth Drivers
- EUV and advanced-node patterning
- New semiconductor fabs in Japan and overseas
- Rising material intensity per wafer
- Demand for geographically resilient chemical supply
Risks
- Rapid lithography technology shifts
- Customer qualification and concentration
- Raw-material and environmental regulation
- Capacity expansion ahead of demand
Key Points to Watch
- EUV material sales
- Aso Kumamoto Site utilization
- Koriyama capacity expansion
- Overseas production and customer mix
Official Sources
Editorial note: This independent profile is based primarily on company-published information. Business conditions and plans may change. SemiStructure is not affiliated with the company, and this page does not constitute investment advice.
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