Message from CEO

Technology the Right Way – As a 90-year-old manufacturer
Okamoto was established more than 90 years ago as a manufacturer of gear grinding machines.
Thanks to the people who concerned, Okamoto became the “Total abrasive processing machine manufacturer”, is producing machine tools and semiconductor processing equipment , and is contributing to the high-quality and high-precision machining in the world aiming to the next-generation manufacturing.
Proud to be a manufacturer with visions and technology to see the “World”
Okamoto has had a global vision for 50 years. We established a manufacturing site of conventional machines in Singapore, a site with the integrated system from casting, parts manufacturing to assembling in Thailand, and other sales & service bases around the world.
Okamoto has earned the trust by Japanese and International customers for the technologies and quality which is accumulated in its long history.
Nearing to 100th anniversary, Okamoto will strive to further improve and develop our total technology together with the Okamoto group employees in the world, for the customers, employees, and societies.
Our motto is “Technology the Right Way.”
Our ideal goal is creating something beyond customers’ needs.
We will further challenge as a unique “total abrasive processing machine manufacturer” in the world.
We appreciate your warm support and frank opinions.
COMPANY PROFILE
[ Head Office / Annaka factory ]
2993 Gobara,Annaka,Gunma,379-0135 JAPAN
Company & products History
A 90-year tradition of craftsmanship in machine tool manufacturing,
passed down from generations of predecessors.
Kakuzaburo Okamoto founded Okamoto Specialized Machine Tool Manufacturing Co., Ltd. as a privately owned business.

Developed Japan’s first gear grinding machine, the ASG-2 model.
The company changed its name and organization to Okamoto Machine Tool Works, Ltd.
and established its head office at 3-4 Ginza, Kyobashi-ku, Tokyo.
The Yokohama Factory began operations with the relocation of some of the equipment from the Yaguchi Factory, which was the main factory at the time, and the construction of new facilities.
The company changed its name and organization to Okamoto Machine Tool Works, Ltd.
and established its head office at 3-4 Ginza, Kyobashi-ku, Tokyo.
The Yokohama Factory began operations with the relocation of some of the equipment from the Yaguchi Factory, which was the main factory at the time, and the construction of new facilities.
Relocation of Tokyo Head Office to Kohoku Ward, Yokohama City.
The entire headquarters and Yokohama factory were seized by the US military.
Market trading of our company’s shares was naturally suspended as a result of the above seizure.
Merger with Hosoda Machinery Co., Ltd.
Started manufacturing surface grinders.
Developed Japan’s first surface grinder, the PSG-6 model.

Developed the IGM series of internal grinding machines.
Developed Japan’s first PSG3Ge type peripheral blade slicing machine.
Complete lifting of seizure of head office and Yokohama factory.
Establishment of development and production system for surface grinders and various other machine tools.
Listed on the Second Section of the Tokyo Stock Exchange.
Developed the world’s first CNC flat and form grinding machine, the NFG-5 model.
Developed the world’s first CNC flat and form grinding machine, the NFG-5 model.
Developed the OGM series of cylindrical grinding machines.
Established OKAMOTO CORPORATION as a sales company in Chicago, USA. (currently a consolidated subsidiary)

Spun off the gear division of the Hiroshima Plant and established Okamoto Gear Co., Ltd.
Established OKAMOTO (SINGAPORE) PRIVATE LIMITED, the first local subsidiary to manufacture machine tools in Singapore (currently a consolidated subsidiary).
Started manufacturing machine tools in Singapore, the first in the country.

Developed the PRG series of rotary surface grinders.
Hiroshima Factory spun off to form Okamoto Engineering Co., Ltd., which will be responsible for manufacturing small models.
Service division spun off to form Okamoto Engineering Service Co., Ltd.

Established Sanyo Okamoto Co., Ltd. to handle sales in the Hiroshima area.
Annaka Plant Completed and Begins Operations in Annaka City, Gunma Prefecture.
Our affiliate Okamoto Giken Service Co., Ltd. changed its name to Giken Co., Ltd.
Yokohama Plant relocated and closed; Atsugi Plant opened in Atsugi City, Kanagawa Prefecture.
New Atsugi Plant Completed and Begins Operations.
Our subsidiaries Okamoto Machine Co., Ltd., Okamoto Gear Co., Ltd., and Sanyo Okamoto Co., Ltd. merged to form a new company, Okamoto Machine Co., Ltd. (currently a consolidated subsidiary).
Developed the best-selling PFG500 series of general-purpose grinding machines.

Established OKAMOTO (THAI) CO., LTD. in Thailand (currently a consolidated subsidiary)
Developed the best-selling PSG-DX series of general-purpose surface grinders.

The second phase of construction at the Anzhong Factory has been completed.
Acquired Nissho Co., Ltd. and made it a subsidiary.
Business alliance with US machine tool manufacturer.
Established OKAMOTO MACHINE TOOL EUROPE GmbH, a local subsidiary in Germany (currently a consolidated subsidiary)
Acquired Shibayama Machinery Co., Ltd. and made it a subsidiary.

Okamoto (Singapore) Pte, Ltd. obtains ISO 9002 certification.
(a first in the machine tool industry in Asia)
Established a branch office in Singapore as a sales and service base.
Merger with Shibayama Machinery Co., Ltd.
Establishment of Semiconductor Business Division.
Received the Japan Society of Mechanical Engineers Technical Award for the development of a fully automatic vertical high-precision surface grinder.
Received the Abrasive Processing Society Technical Award for the development of a fully automatic high-precision, high-efficiency CMP device.
Sales of the best-selling PSG-DX series of general-purpose surface grinders exceeded 5,000 units.

Relocation of head office to Atsugi City, Kanagawa Prefecture (Atsugi Factory)
Establishment of a representative office in Shanghai, China.
Relocated main office to Annaka City, Gunma Prefecture (Annaka Factory)
Relocated headquarters to Kohoku Ward, Yokohama City.
Completion of clean room for testing and inspection of semiconductor-related equipment at Annaka Plant.
Completion of temperature-controlled processing and assembly booth at Annaka Plant.
Completion of new assembly plant at Okamoto (Thai) Co., Ltd.

Spindle room completed at Annaka Plant.
New casting plant completed at Okamoto (Thai) Co., Ltd.
(Combined production capacity of old and new plants will be 1,800 tons per month)

Okamoto (Thai) Co., Ltd. completes sheet metal and painting factory.
As equipment for the Annaka Factory,
the world’s largest ultra-precision gate-type surface grinder UDG10035NC with a hydrostatic guideway system has been completed.

Integrated Singapore branch into OKAMOTO (SINGAPORE) PRIVATE LIMITED.
iQ software developed to convert flat grinding know-how into software. Development of machines equipped with iQ software.
Development of PSG-CHLi series CNC gantry-type precision flat grinding machines to meet the demand for high precision and high efficiency in large workpieces such as progressive dies.
In order to meet the demand for micro-forming of small parts,
we have developed the UPZ210LiⅡ ultra-precision forming grinding machine driven by a linear motor.
Relocation of head office to Annaka City, Gunma Prefecture (Annaka Factory)
A new Machinery Division will be established at Okamoto Engineering (Changzhou) Co., Ltd., a Chinese subsidiary of Okamoto Engineering Co., Ltd., and the Shanghai Representative Office will be transferred to that division (currently a consolidated subsidiary).
Our subsidiaries Giken Co., Ltd. and Nissho Co., Ltd. will merge to form a new company, Giken Co., Ltd. (currently a consolidated subsidiary).

Development of UGM360NC CNC Precision Composite Cylindrical Grinding Machine.
Announced at JIMTOF2014, the 28th Japan International Machine Tool Fair.

Held the OPENHOUSE 2015 exhibition to commemorate the 80th anniversary of the company’s founding.
Announced “Grinding Revolution” as the theme for the 80th anniversary.
Developed the HPG500NC series of high-precision forming grinding machines.
Developed the SELF fully automatic surface grinding system.
Developed PSG-SA1 series precision surface grinding machines.
Developed the IGM15NⅢ-2B precision internal grinding machine.
Developed the UDG-Li series of CNC precision gantry surface grinding machines.
Launched the Quick Touch in-flight measurement system.
The ASG-2 spur gear grinding machine owned by Nippon Institute of Technology Museum of Industrial Technology was certified as No. 106 on the Japan Society of Mechanical Engineers’ list of mechanical heritage items.
Established OKAMOTO INDIA PRIVATE LIMITED as a sales company in India.


Transition to the Tokyo Stock Exchange Standard Market
Three newly developed models exhibited at JIMTOF 2022
・CNC precision surface grinder PSG126CA-iQ
・Vertical rotary surface grinder VRG-DX series
・Grinding center UGM64GC

Acquired all shares of Daiwa Koki Co., Ltd. in Miyakonojo City, Miyazaki Prefecture, making it a wholly owned subsidiary (currently a consolidated subsidiary).
Acquired the flat grinding machine manufacturing and sales business from Nikko Co., Ltd. in Nagaoka City, Niigata Prefecture, and established NICCO Co., Ltd., a new wholly owned subsidiary of our company.
Established the Kyushu Technical Support Center to expand our semiconductor service base.
Received the SUMCO Supplier Award.


Concluded a capital and business alliance agreement with Mitsui & Co., Ltd. and implemented a third-party allocation of new shares to Mitsui & Co., Ltd.
Si through-electrode wafer fully automatic grinding equipment recognized as a successful development by the Japan Science and Technology Agency.
Environmental policy
- For global environmental protection, promote better technologies and products to supply products.
- Considering Technical and Economical circumstances make an effort toward prevention of environmental pollution and reduce influence to the environment with the business activity.
- In the course of their business activities, energy, will strive to reduce the environmental impacts by the reduction of such waste.
- Established environmental policy, environmental objectives and targets, we strive to achieve this, by making the regular review, and promote continuous improvement.
- Laws and regulations on the environment, and will comply with other requirements to which we agree.
- This environmental policy will be published in both inside and outside the company.
Establish worldwide quality control system, ISO 9000 acquired at 3 domestic and overseas factories.
Including the Annaka factory that became the forerunner of full air conditioning plant in a semi-underground structure, Thai plant and Singapore plant, we have gotten a high reputation in the facility environment.
Strictly efforts in quality control, get the first authentication of ISO9002 in Asia machine tool industry in 1994 at the Singapore plant, Annaka in 2004 plant, Thai plant was also obtained ISO9001 in 2005.


EFFORTS at the manufacturing site
The Annaka plant having central coolant fluid management system for machines in Constant temperature room and also silicon slaggy management system for semiconductor equipment testing in clean room.
Along with the re-use filtered processing liquid waste, such as to significantly reduce the industrial waste generated in the filtration process, we are working to reduce the environmental load.
Casting was newly formed in the Thai plant , aiming to clean foundry, it has become a dust and dust collection of gas, plant that was also friendly to sand recovery and reuse and environmental equipment.

central coolant fluid management system
(Annaka plant)

The latest environmental equipment
(Thai plant)
Relation with the end product
Abrasive processing is an important role as one of the backbone processing technology to support the IT ,
digital consumer electronics, automotive and semiconductor industry.

1. wafer processing
Flash memory and SD Card, have been recently equipped with a number of IC in automobile.
Polishing machine machine for Wafer material manufacturers and Grinder for device manufacturers keep a higher market share.





2. transmission fear
Automotive transmission gear reduces the gear noise by precision grinding, to increase the quietness, it will also contribute to improved fuel efficiency. Our Gear grinding machine has been used in this field.
Also Okamoto Koki Co., Ltd. manufacture and sale of the gear.







3. ultra thin and narrow pitch connector
Mobile phones from the need to process a large amount of information by simultaneous and thinner and lighter, it is increasingly low profile and a narrow pitch of the connector to be used.
Form grinding machine will be able to finish without deflected a slight 0.05 mm fine carbide punches.





4. manufacture process for large lcd tv
There are many Grinding and Polish process to making mother glass for LCD TV panel, coating nozzle and photo-mask.
By finishing such large parts in high level of flatness can to obtain a wide viewing angle.
Okamoto can provide a large grinding and polishing equipment is the only one in the world.







5. engine parts for airplane
Turbine blades to minimize thermal expansion occurring by higher temperatures, becoming engagement shape called Christmas tree from its shape, and made out with grinding.
It boasts one of the world’s leading share in the blade processing machine including the Christmas tree.





6. Bearing prcess
Automobile, machinery and Airplane are using bearing as functional components into rotation unit.
Our internal grinder, cylindrical grinder, rotary surface grinder is also active in this field.





