Notice Regarding Start of Operation of Aso Plant Aso Kumamoto Site

Tokyo Ohka Kogyo Co., Ltd. (Head Office: Nakahara-ku, Kawasaki City; President: Noriaki Taneichi; hereinafter 'the Company') hereby announces that the newly established 'Aso Plant Aso Kumamoto Site' in Kikuchi City, Kumamoto Prefecture has commenced operations.

The Company opened the Aso Plant (Aso City, Kumamoto Prefecture) in 1984 and has been manufacturing high-purity chemicals. In recent years, with the expansion of semiconductor production in the Kyushu area, the Company established the Aso Kumamoto Site to meet increased demand and further strengthen the stable supply system, completing construction in 2024.

The site is equipped with facilities enabling strict quality control, contributing to improved quality and stable supply of high-purity chemicals. With the start of operations, the Company aims to expand supply capacity through synergy with the Aso Plant and further enhance user support in western Japan.

The Company group, in order to achieve the desired state set forth in the long-term vision 'tok Vision 2030', plans capital investment totaling 76 billion yen over three years in the 'tok Medium-Term Plan 2027' started in fiscal 2025, the largest scale in its history. Going forward, to respond to medium- to long-term growth in the semiconductor market, the Company will proceed with capacity expansion and stable supply system development both domestically and internationally, and focus on quickly bringing each investment project online, leading to the acquisition of new cash generation capabilities.

Record

1. Overview of Aso Plant Aso Kumamoto Site

Name: Aso Plant Aso Kumamoto Site

Location: 987-2, Niitooki, Asoshikawabe, Kikuchi City, Kumamoto Prefecture

Purpose: Supply and quality control of high-purity chemicals

Site Area: 128,000 square meters

Investment Amount: Approximately 13 billion yen

Aso Plant Aso Kumamoto Site

2. Future Outlook

The impact of this matter on the Company's results is already reflected in the consolidated earnings forecast announced on February 9, 2026.

Related Releases

Notice regarding completion of new plant at Aso Plant Aso Kumamoto Site | Tokyo Ohka Kogyo Co., Ltd.

Notice regarding establishment of new Aso Plant Aso Kumamoto Site in Kikuchi City, Kumamoto Prefecture | Tokyo Ohka Kogyo Co., Ltd.