TOK has made and will continue
to make contributions to society.

TOK ensures that all management resources and initiatives ultimately contribute to society under the four management principles (Create a frank and open-minded business culture, continue efforts to enhance our technology, raise the quality levels of our products, and contribute to society). In the coming years, TOK will contribute to a sustainable future through chemistry, thereby supporting the sustainable development of an affluent society.



DNA in place since TOK’s founding

Under his strong ideal of challenging ourselves to develop products, however hard it may be, useful to society, and not offered by other companies, the founder, Shigemasa Mukai, developed thebatteries used in the lights on coal miners’ caps in 1934 after more than six years of trial and error, thereby enhancing safety in the coal industry in the early Showa era.


Helped ensure the safety of the coal industry at the outset of the Showa era with potassium hydroxide of a purity greater than that of imported products.



Realized the domestic production of potassium silicate, which is essential for the manufacture of cathode-ray tube televisions. Helped reduced the costs of manufacturing television sets and contributed to the widespread use of televisions in Japan.



Acquiring TOK’s reputation as a supplier of photoresists.

TOK started the full-scale photoresist business in 1968, developed an eco-friendly synthetic rubber resist in 1971, and then created the first semiconductor positive photoresist in Japan in 1972 by leveraging its high purification technology and microprocessing technology. The Company has acquired a reputation as a supplier of photoresists indispensable for semiconductor production and has supported increasing efficiency in business by contributing to the higher performance of pocket calculators and the emergence of word processors and PCs.



Developed OMR81 (negative photoresist for semiconductors).


First semiconductor positive photoresist "OFPR-2" developed in Japan.


Developed the high-precision nonmetallic developing solution NMD-3. The concentration of developing solution for this product came to constitute a global standard.


Opened the Utsunomiya plant as the first full-scale semiconductor photoresist mass-production plant in operation.


Built Aso plant.


Built Gotemba Plant.It boast some of the most advanced facilities available, including the world's first metal-free configuration for a photoresist production line.


Toward a global niche top company.

TOK established its first overseas manufacturing plant in Oregon, USA, in 1993. and strengthened its structure for increased production by opening the Koriyama plant in 1994. The KrF excimer laser photoresist, which TOK developed in 1997, has been used by many semiconductor manufacturers as the global standard. TOK continued to strengthen its development and production systems in Japan and overseas, thereby solidifying its position as the top global manufacturer of photoresists in the high-added value niche field.



Opened the company’s first overseas manufacturing plant in Oregon in the USA, in 1993.


Opened the Koriyama plant as the company’s primary production site in Japan.


Established TOK Taiwan Co., Ltd. to raise the profile of the company in Taiwan, the world’s largest market for semiconductor materials.


Enhancement of the Customer-oriented strategies.

TOK increased the overseas sales ratio that over 50% in 2004. To strengthen customer-oriented strategies in Asia with remarkable growth in the semiconductor industry, TOK Advanced Materials Co., Ltd. (South Korea) was established in 2012, and the Tongluo Plant of TOK Taiwan Co., Ltd. was established in 2014. A similar structure was also bolstered in the United States and Japan in response to the raw voice of customers through the trinity of development, manufacturing, and sales, while enhancing its marketing force, thereby establishing strengths in the cutting-edge semiconductor field of EUV photoresists.

最終製品例:スマートフォン、ArFレジスト / EUVレジスト


Developed high-density mounting materials and embarked on the downstream processing of semiconductor manufacturing.


Established TOK Advanced Materials Co., Ltd. in South Korea to accelerate the company’s client-focused strategy in Asia.

Tokyo Ohka continues to evolve
to aim to be a '100-year company'.

Since commemorating the eightieth anniversary of the company’s founding in 2020,
TOK formulated a new management vision (“The Material Global CompanyTM - Contributing to a sustainable future through chemistry”)
and has been working to realize TOK Vision 2030,
a long-term vision with a focus on where the company hopes to be in 2030.
TOK is also working to create new businesses with the aim of becoming a 100-year company in 2040.


Update on research and development locations

Restructuring the Sagami Operation Center (present TOK Technology and Innovation Center (TTIC) ),
which serves as the hub of the TOK Group’s research and development locations.

Creating the new buiness
to a sustainable future.

With a view to becoming a 100-year company, the aim is to create the new business that can stand alongside the current business segments of photoresists and high-purity chemicals.

for 2030.

TOK aims to become an e-Material Global CompanyTM with a focus on other aspects of growth for the semiconductor market.