Company

Company Profile

Company Name SEI Optifrontier Co., Ltd.
Founded On May 15, 1915, Predecessor of Toyokuni Electric Cable, Co., Ltd., started its operation as Toyokuni Electric Cable Factory.
Business Started as SEOF July 1, 2010
Representative President Koji Niikura
Capital 660 million yen
Shareholder Sumitomo Electric Industries, Ltd.
Number of Employees 1,000 (consolidated)

History

A Brief History of (Former) Toyokuni Electric Cable Co., Ltd.

1915
  • Toyokuni Electric Cable Factory was founded in present Negishi, Taito-ku, Tokyo.
  • Started manufacturing electric cords/cables.
1939
  • Sasaki Manufacturer Co., Ltd. was established in present Hamamatsu-Cho, Minato-ku, Tokyo.
  • Started manufacturing magnet wires and rubber wires.
1962
  • The factory of Sasaki Manufacturer Co., Ltd. relocated to Gyoda-shi in Saitma.
1967
  • Sumitomo Electric Industries, Ltd. participated in management.
1973
  • The two companies were merged on April 1, starting with a capital of 200 million yen, under the new name, Toyokuni Sasaki Electric Cable, Co., Ltd.
1975
  • Started manufacturing cable harness for buildings and houses.
1979
  • Headquarters relocated from Torano-Mon, Minato-ku to Mianmi-Ikebukuro, Toshima-ku, in Tokyo.
1983
  • TSE Inc. was established.
1986
  • On October 1, the company name was changed: Toyokuni Electric Cable, Co., Ltd.
1987
  • A new factory for optical fiber cables started its operation.
1989
  • Increase in capital: 661,605,050 yen
  • Saitama Toyokuni Inc. was established.*
1990
  • Yamanashi Toyokuni Inc.* and TKK.Inc.** were established .
1991
  • Started manufacturing connectorized optical cables.
  • Tohoku Toyokuni Inc. was established.*
1994
  • T&D Inc. was established.**
1995
  • Started delivering optical fiber cables for telephone exchange to Nippon Telegraph and Telephone Public Corporation (NTT).
1996
  • Toyokuni Engineering Services Inc. was established.**
  • Obtained ISO 9001 certification.
1997
  • Kansai Toyokuni Inc. was established.*
  • Obtained NQAS certification (NTT's New Quality Assurance System)
1999
  • Started manufacturing optical fiber couplers.
2000
  • Obtained ISO 14001 certification.
2001
  • Chichibu Toyokuni Inc. was established.**
2002
  • Shikoku Toyokuni Inc. was established.*
2010
  • Transferred the business related to wire/cable harness to Sumitomo Electric Industrial Wire and Cable Inc., being merged into a new company, SEI Optifrontier Co., Ltd.
*: Subsidiaries for information communication-related industries
**: Subsidiaries for housing and building-related industries.

A Brief History of (Former) Sumiden High Precision Co., Ltd.

1938
  • Established as Showa Kikai Kogu Co., Ltd.
  • Started manufacturing cutting tools for airplane production.
1942
  • Suwa Plant was opened in Ochiai-mura, (present Fujimi-machi), Suwa-gun, Nagano.
1947
  • Started manufacturing adjustment tools for communications equipment under contract with Teishinsho or former Japanese Ministry of Posts and Telecommunications.
1956
  • Started manufacturing coaxial terminals and connection tools for coaxial cables.
1978
  • Sumitomo Electric Industries, Ltd. participated in management.
1983
  • Started delivering fiber optic tools, optical connectors, and cords with optical connectors to Nippon Telegraph & Telephone Public Corporation (predecessor NTT).
1984-1991
  • Started delivering to Nippon Telegraph & Telephone Public Corporation (predecessor NTT): connector connection tools for digital switching machines, fire resistance covers, fiber detectors for cable tunnels, evacuation lights, connectors for GI optical cables, and SC type optical connectors.
1992
  • Headquarters relocated from Meguro-ku, Tokyo, to Chigasaki-shi, Kanagawa.
  • Changed the company name to Sumiden High Precision Co., Ltd.
  • Started manufacturing MT connectors.
  • Started manufacturing mechatronics products.
1997
  • Obtained ISO 9001 certification and NQAS certification (NTT's New Quality Assurance System)
2000
  • Started manufacturing optical receiver/transmitter products.
  • Obtained ISO 14001 certification.
2001
  • Completed the construction of Shonan Plant No. 2.
2002
  • Started the operations of Yokohama Plant.
2003
  • Started manufacturing optical modules and optical receptacles.
2004
  • Expanded the operations of Suwa Plant.

2007
  • Opened Fujisawa Center.

2008
  • Celebrated the 70th anniversary of its foundation.
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