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Corporate Overviews
Seiko Chemical Corporation Overviews
    Polymerization inhibitors/intermediates for Dyes and Pigments
Fine chemicals are supporting our comfortable lives, through we remain unaware of them. Our products are contributing much to this field. There are various types of fine chemicals such as:
1. Polymerization inhibitors for stabilizing the raw materials for synthetic resins such as superabsorbent polymer to be used for paper diapers and synthetic fibers
2. intermediates for dyes such as hair dyes and pigments
3. Photopolymerization initiators used for photosensitive resin plates for printing and photo developing agents
4. Antioxidants for feed and fertilizers used in agriculture and stock farming
5. Other chemicals such as epoxy resin catalytic agents and corrosion inhibitors
Behind the scenes, these chemicals contribute to the quality of products indispensable for a comfortable lifestyle. It is our hope to provide you a warm and tasteful life by breathing life into the unseen chemical world around you.

Rubber/Plastic Processing Chemicals
Around us, we can find a great number of rubber products such as car tires, belts, golf balls and rubber bands. these rubber products are aged by oxygen, ozone in the air and/or heat. If rubber bands are left stored long in a drawer, for example, they may become sticky or easily broken. Car tires may be cracked if they have been used for a long period of time. these aging phenomena may lead to the shortened service-life of rubber products. It is the antioxidants that prevent the aging of products and ensure that those products have a long life.
By making the most of our long-accumulated high-technical skills, we have recently developed the rubber anti-tack agents named "NEWAID" capable of remarkably improving the working environment for users and ensuring better maintenance rubber products. "NEWAID" is highly evaluated by our customers.
Also in the future, we intend to help to ensure that you feel easy using the rubber products that play a part in all our lives.
Research & Development
A ceaseless search for new compounds snd diligent development of new applications from existing compounds are sought after to meet the needs of the 21st century.
In order to meet those needs, we are promoting an innovative "Technology & Revolution" program aiming at ecological solutions.
Our Reseach & Development Division is constantly working to unearth new chemical substances and pursuing the challenges of developing new applications from existing compounds while striving to stay in harmony with the environment.
Furthermore, we are streamlining, the internal manufacturing procedures and combining our accumulated synthesis and manufacturing technologies in order to effectively manage entrusted reseach and manufacturing partnerships.
In this progressive environment, we are continuously exploring new and diversified themes with a bright future in mind.
Production & Quality Control
We, Seiko Chemical, are manufacturing products based not only on hydrogenation, alkylation, chlorination and condensation reactions in our line but also those based on other various chemical reactions.
The production equipment consists mainly of multi-plant and batch system suited for finechemicals subject to multikind and small quantity production. This has all been established by our company's own techniques from the development of processes, to construction of plants.
At the jobsite, each person has a critical imput into the production activities and is constantly seeking improvements and modifications with a view to achieving higher efficiency of production equipment.
Furthermore, with the setting of global standards, we are making efforts to establish a quality system for assuring the products capable of meeting production for the needs of customers not only in Japan but also overseas. In addition we strive for a friendly global environment. Our products, which are produced based on a strict quality control system , under close cooperation with our quality control division, manufacturing division and technical division, are highly evaluated by our users.
Date of establishment April 1946
Capital 120,000,000 yen(Total capitals:5,690,000,000 yen Net worth:3,960,000,000 yen)
Kohei Miyama, president
Katsumi Nishihara, managing director
Tatsushi Watanabe, director
Makoto Igarashi, director
Osamu Takeda, auditor
Takeo Tohara, auditor
Nummber of employees 150
Sales:Annual turnover 4,095,000,000 yen (as of September 2022)
Business items   Manufacture and sale of Industrial chemicals such as antioxidants and other rubber/plastic processing chemicals,polymerzation inhibitors and intermediates for dyes and pigments.
Main banker MUFJ Bank, Ltd.
1946   Established under the name of Kimijima Research Institute in Shimo.kita-ku,Tokyo.Several talented enjineers raillied around the late Dr.Eng.Takuzo Kimijima and succeeded in commercialization of the production technique for organic rubber/plastic processing chemicals for the first time in japan.
1947 Reorganized into a joint-stock company and was named Seiko Chemical CO.,Ltd.
Capital:195,000 yen
President:Takuzo Kimijima
1948 Started with production of HYDROQUINONE(photo chemicals)
1949 Constructed Shimura Plant in Azusawa,itabashi-ku,Tokyo.
Started with production of NON-FLEX H.F.D(antioxidant).
1953 Started with production of NON-FLEX, Alba(antioxidant).
1955 Started with production of SUNTIGHT(Surface Crack Protective Agent).
Started with production of DIEHY and DIMEHY(intermediates for dyes and pigments)and NONFLEX BA(antioxidant).
1956 Capital increased to 4,000,000 yen.
1957 Sales office opened in Nihonbashi ,Chuo-ku,Tokyo.
1959 Newly established Osaka Branch.
Started with production of NON-FLEX AW(antioxidant).
1960 Constructed Kawaguchi Plant in Kawaguchi City,Saitama Pref.
Started with production of BHT SWANOX(Non-staining antioxidant).
1961 Started with production of METHOQUINONE(polymerization inhibitor).
1962 Started with production of OZONONE 3C(Antioxidant).
1965 Capital increased to 8,000,000 yen.
1966 Shimura Plant was moved to and integrated with Kawaguchi plant for centralized production.
1967 Exported the production technique for XOZ(OZONONE 3C)to USSR.
1969 QC seminar was commenced.
1971 Recognized by MITI as a Grade A Export Contributing Company.
1972 Capital increased to 40,000,000 yen.
1974 Capital increased to 80,000,000 yen.
No.4 SUNTIGHT production plant was completed.
1975 Capital increased to 100,000,000 yen.
Welfare Center(within the premises of Kawaguchi Plant)was brought to completion.
1979 Biological Waste Water Treatment(within the premises of Kawaguchi Plant)was completed.
1981 Capital increased to 120,000,000 yen.
Started with production of NEWAID(rubber antitack agent).
1982 Started with production of OZONONE 6C(Antioxidant).
1983 Started with production of PBQ(polymerization inhibitor).
1990 Equipment for increasing the production of PHENOTHIAZINE(polymerization inhibitor)was completed.
1995 Equipment for increasing the production of METHOQUINONE(polymerization inhibitor)was completed.
2001 Obitained ISO 9002 certification
2003 Obitained ISO 9001 certification
Sun Chemtech Co.,Ltd
Date of
October 1963
Business items   Sales of organic and inorganic chemicals
Capital 30,000,000 yen (Wholly-owned by Seiko Chemical)
Sales 1,570,000,000 yen
Head office Matex No2 Blidg. 1-9-10 Matsugaya Taitou-ku, Tokyo
Branch Osaka Sales Office
Head office Kaede building 2-3-6, Uchikanda, Chiyoda-ku,101-0047 Tokyo
Phone:03(3254)2771(Key number) FAX:03(3258)1431
Hanabusa Bldg.,1-2-2 Doshomachi,chuo-ku,541-0045 Osaka City
Phone:06(6231)4361(Key number) FAX:06(6231)5202
1-15-33 Yanagisaki,Kawaguchi City,333-0861 Saitama Pref.
Phone:048(265)3412(Key number) FAX:048(265)3415
1-15-33 Yanagisaki,Kawaguchi City,333-0861 Saitama Pref.
Phone:048(265)4772(Key number) FAX:048(261)7731