About ISK



Sep. 1920 In Osaka, Hiroichiro Ishihara established Nanyo Mining Partnership Co., a firm dedicated to iron mining in Surimedan, Johol on the Malay Peninsula.
May 1924 Purchased an iron and manganese mine in Kemaman, Torenganu on the Malay Peninsula.
Aug. 1929 Renamed the Firm to Ishihara Sangyo Marine Partnership.


Mar. 1934 Reorganized the Firm into a limited company. Opened the Kishu Mine (copper and sulfide ores) in Mie Prefecture.
Oct. 1938 Began building Yokkaichi Plant in Mie Prefecture. (Completed copper refinery and sulfuric acid plants in January 1941.)


Jun. 1943 Transferred shipping business to Nihon Marine Co., Ltd. Renamed the Firm to Ishihara Sangyo Kaisha, Ltd.
Jun. 1949 Dissolved the Firm in compliance with the Industrial Readjustment Law. Restarted operations under the new company: Sanwa Mining & Industrial Co., Ltd., which was renamed Ishihara Sangyo Kaisha, Ltd. the same month.
Jul. 1949 Listed Company’s stock on the Tokyo and Osaka Stock Exchanges.


Apr. 1950 Constructed a herbicide plant in Yokkaichi.
Jul. 1952 Constructed a chemical fertilizer plant in Yokkaichi.
Mar. 1954 Constructed a sulfate processed titanium dioxide plant in Yokkaichi.
Jun. 1958 Opened a research institute in Yokkaichi, which was renamed the Central Research Institute in June 1963.


Jul. 1961 Constructed a ammonium sulfate plant in Yokkaichi.
Mar. 1963 Constructed a titanium yellow (yellow pigment) plant in Yokkaichi.
Apr. 1965 Relocated the Central Research Institute to Kusatsu, Shiga Prefecture.


Sep. 1970 Completed a wastewater treatment facility in Yokkaichi.
Jun. 1971 Constructed a synthetic rutile plant in Yokkaichi. (Stopped production in March 1994.)
Oct. 1974 Constructed a chloride processed titanium dioxide plant in Yokkaichi.
Dec. 1974 Constructed a sulfuric acid plant in Yokkaichi that employed the sulfur combustion method.
Jan. 1976 Transferred fertilizer manufacture and marketing business to Ishihara Hiryo Kogyo Co., Ltd. (dissolved in February 1990)
May 1978 Closed the Kishu Mine.


Oct. 1981 Constructed an organic intermediate CTF plant in Yokkaichi.
Dec. 1983 Constructed a magnetic iron oxide plant in Yokkaichi.
Aug. 1986 Established ISK SINGAPORE PTE. LTD., ISK's subsidiary in Singapore, and constructed a chloride processed titanium dioxide plant.
Aug. 1989 Transferred agrochemicals marketing business in Japan to Ishihara Sangyo Agrochemicals Co., Ltd., one of ISK's subsidiaries. (now ISK Biosciences K.K.)


Nov. 1990 Purchased SDS Enterprise in the U.S. (now ISK Biosciences Corporation)
Apr. 1991 Purchased magnetic materials business from Harcros Pigments Inc. in the U.S. (now ISK MAGNETICS, INC.)
Mar. 1993 Completed New Ishihara Building in Osaka. Moved the head office into the new building in April 1993.
Dec. 1994 Established SUD ISK-SNPE S.A., a joint venture in France producing fine chemical products. (Terminated the joint venture in July 2005.)
Jul. 1996 Transferred agrochemicals marketing business in Europe to ISK BIOSCIENCES EUROPE N.V., one of ISK's subsidiaries in Europe.
Feb. 1998 Sold agrochemicals business in the U.S. to Zeneca Limited. (now Syngenta Limited)
Feb. 1999 Commenced custom manufacturing of active pharmaceutical ingredient in Yokkaichi.


Mar. 2001 Withdrew from business of magnetic materials for videotapes.
Dec. 2001 In Yokkaichi, constructed a facility for manufacturing HVJ-E vector for gene function analysis.
Mar. 2005 Acquired 100% ownership of Fuji Titanium Industry Co., Ltd.
Jun. 2005 Decided to recall Ferosilt voluntarily (stopped selling in April 2005) and then, received local governments' orders to take measures under the Waste Management and Public Cleansing Act.
Nov. 2005 Established a joint venture for marketing agrochemicals (ZHEJIANG ISK & TAURUS CHEMICAL CO., LTD.) in China.
Sep. 2006 Formed a business alliance with United Phosphorus Limited (UPL), the largest manufacturer of agrochemicals in India.
Mar. 2008 Reviewed the company's overall compliance status. (Announced findings of the review and measures to prevent recurrence in May 2008.)


Jun. 2010 Launched Environmental Materials on a full scale.
Sep. 2010 Acquired 100% ownership of Yokkaichi Energy Service Co., Ltd., a private electricity generating company.(Absorbed the company for merger in October 2018.)
Aug. 2013 Shut down the chloride processed titanium dioxide plant of ISK SINGAPORE PTE. LTD.(Completed liquidation in March 2020.)
Dec. 2015 Completed the final disposal of Ferosilt.
Sep. 2018 Received approval for manufacturing and marketing of a veterinary drug in Japan.