History and Achievements


1939 Our founder, Hirotsugu SAITO, established NIHON GENRYO for the purpose of manufacturing and selling sand to be used as glass materials
1940 Established plants in Takahagi -city and Isohara -town (in Kita-ibaraki -city at present) and also started conducting the collection and sale of glass materials and casting sand
1945 Started forming the basis of a company specializing in filter media under the guidance of the General Headquarters (GHQ) and related government offices
1950 Built a new factory and office in Kizugawa, Kyoto
1951 Established the Japan Filter Sand Laboratory to promote quality control and technical development based on the JWWA Standard set by the Japan Water Works Association. Appointed a member of the Hygiene Survey Commission of the Japan Water Works Association
1954 Invented a patented high-speed sand washing system and established a system for mass production thereof. Obtained a patent for a system to scrape away the surface sand of slow filters and more than 60 other patents and utility models.
1968 Our first company president Hirotsugu SAITO received the Medal of Merit from the Japan Water Works Association due to his contribution to the development of waterworks through efforts in inventing a sand sieving and washing system for filtration sand for water supply and conducting research on the improvements of filter media
1969 Our first company president Hirotsugu Saito received the Medal of Blue Ribbon from former Prime Minister Eisaku SATO for his contribution to the development of the industry
1970 Kin SAITO assumed the presidency
1982 President Kin SAITO received the Health and Welfare Minister’s Award for her long-term efforts for diffusion and development of water supply systems and remarkable achievements.
Exporting 4 (four) “Fully Automatic Dust Scrapers” to Bangkhen Water Purification Plant of Bangkok Metropolitan in Thailand.
1985 Participated in the establishment of JWWA A-103-1988 (standard for the method of testing filter media for water supply) of the Japan Water Works Association as a member of the Specialized Committee on the Testing of Filter Sand for Water Supply System
1989 Death of the SHOWA EMPEROR. NIHON GENRYO dedicated white sand as paved sand in the funeral hall at the time of the state funeral of the emperor.

Manfacturing factory

Roots of NIHON GENRYO Takahagi Factory

Takahagi factory has produced high quality filter media with a focus on the important role of filter media for the water supply system since the factory was established in 1940. Using our experience, which we cultivated over many years, we established the automation product system which includes a high degree of flexibility, reliability and efficiency. Under our concept, which is “Apart from conventional production technology which depends on human resources and experiences”, our Takahagi factory was renovated in July, 1995 under the T.F.A project (Takahagi Factory Automation project). After the renovation, we have produced a large amount of high quality filter media through the 24- hour operation system. Also, we use “Siphon Tank”, which was our new product, to filter and reuse the drain water in the factory for 24 hours, thus contributing to the environment. We will keep improving and developing our facilities to provide high quality and low cost products in a short period of time.

Certified factory by JWWA


Automatically facility etc.

(Yasuhiro Hirotsugu 24hour Automation)

This is the 24-hour Automated Production System for filter media. The YH comes from the name of the first president, Hirotsugu Saito, who gave us know-how, and the current president, Yasuhiro Saito, who innovatescutting-edge technology.Automation facilities

(Production facility for filter media)

Automatically screening the filter media with washing, and conveying the media outside of the factory

(Production facility for filter sand)

Filter sand sifted on-site is carried by conveyor to the pit

Automatic filer machine

Automatically filling up small bags and piling up on a palette.

Siphon Tank for drain water

Adopting our device, “Siphon Tank”, to filter and reuse the drain water. The filtered water is reused for washing water in the factory.

(For production of Manganese sand)

Realizing a higher amount of production, compared to the conventional way of, sun drying. Also, producing special media is possible, using the drier.

SIPHON factory

Warehouse for storing SIPHON Tank and Mobile SIPHON Tank inventory

Aerial photo of Takahagi factory

The white tent at the top left is the SIPHON factory.
The building with the red roof adjacent to the central pond is YH-24A

Research Center

Established the research center in the area of Takahagi factory to analyze the quality of our production.


“Regional Environmental Technology Prize of the 19th Kanagawa High-Tech. Grand-Prix”
November, 2012

“Award of Excellence in the Technology/Product Sector of the 15th SME New Technology / Product Award”
April, 2003

“Incentive Award Kanagawa Business Audition in 2003”
November, 2003

“22nd Kawasaki Best Entrepreneur Award of the Kawasaki Entrepreneur Competition-Business Idea-Seed Market”
February, 2004

“National commendation invention of grand prize of the Prize of the Chairman of the Japan Chamber of Commerce and Industry”
July, 2005

“Prizes for Science and Technology in Technology Category of The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology”
April, 2007

”The 5th Infrastructure Maintenanse Award
Ministry of Defense Excellence Award Technology Development Category”
Decenber 2020