| March 1953 | Founder Tokuichi Yokoyama opened a laboratory in Shibuya, Tokyo, and started trial manufacture and research of control valves. |
|---|---|
| February 1957 | Established a stock company with capital of 1 million yen under the name of "TOKO Laboratory Co., Ltd." at 2, Hirai, Edogawa-ku, Tokyo. |
| April 1958 | Developed a patented control valve for acid resistance. |
| September 1971 | Established the Osaka office to expand the market to the west of Kansai area. |
| August 1972 | Released V-5000 Series. |
| December 1977 | Certified as a facility for valves for high-pressure gas by the Minister of International Trade and Industry. |
| September 1979 | Increased the capital to 20 million yen. |
| October 1980 | Established Fukushima Factory in Iwaki, Fukushima. |
| July 1982 | Constructed a clean room in Head Factory to begin full production of valves for space development. |
| April 1984 | Established "TOKO Laboratory Engineering Service Co., Ltd." (the present Valex Engineering Co., Ltd.) to expand the service. |
| August 1988 | Iwao Yokoyama assumed the post of president, and Tokuichi Yokoyama assumed the office of chairman. |
| December 1988 | Increased the capital to 30 million yen. |
| August 1989 | Expanded Fukushima Factory to complete the T-8000 process line. |
| February 1991 | Reached a total production of 100,000 globe control valves. |
| August 1992 | Renamed the company as "TOKO VALEX CO., LTD.", introducing CI. |
| February 1998 | Acquired ISO 9001 Quality Management System certification. |
| August 2000 | Delivered various control valves to the nuclear fuel reprocessing facility. |
| May 2001 | Reached a total delivery of 3,000 ultra-low-temperature valves for liquid helium. |
| October 2001 | Delivered large sized (350A) globe control valves to JNC. |
| April 2004 | The company becomes Eco-Action 21 (EA21) certified registered company. |
| August 2005 | Developed a control valve for moisturizing paper machine rollers. |
| June 2006 | Delivered liquefied helium gas relief valves to the neutrino low-temperature facility, J-PARC. |
| August 2008 | Tatsuya Yokoyama assumed the post of president, and Iwao Yokoyama assumed the office of chairman. |
| July 2009 | Set up an agency in China. |
| June 2010 | Started development of valves for rocket engines using LNG as fuel. |
| January 2011 | Succeeded in combustion testing of the LNG rocket engine fitted with our valves. |
| May 2013 | Established Shanghai office. |
| Nov 2020 | Closed Shanghai office. |
| Nov 2020 | Established “TOKO VALEX TRADING (SHANGHAI) CO., LTD.” |