Location History:
- Toyama, JA (1976)
- Niigata, JA (1976 - 1978)
- Asahi, JA (1978)
- Oumi, JP (1980)
Company Filing History:
7 out of 475 
1 out of 50 
1 out of 1 Years Active: 1976-1980
Title: **Koji Nakagawa: Innovator in Concrete Technology**
Introduction
Koji Nakagawa, an esteemed inventor based in Niigata, Japan, has made significant contributions in the field of concrete technology. With a total of seven patents to his name, Nakagawa has developed innovative solutions that enhance the strength and efficiency of concrete moldings.
Latest Patents
One of Nakagawa's notable patents is a concrete composition designed for making high-strength concrete moldings. This invention features a mixture comprising 400-600 kg of Portland cement per cubic meter of concrete, along with 3-30% by weight of insoluble (Type II) anhydrous calcium sulfate and 0.1-3% by weight of a cement dispersing agent. The innovative method he proposed involves pre-steaming the components followed by steam curing under atmospheric pressure; this results in concrete moldings that exhibit both high compressive strength and reduced relaxation, all achievable within a day without the need for autoclave curing.
Another remarkable invention by Nakagawa involves a cement retarder that consists of gluconic acid, tartaric acid, citric acid, and an alkali carbonate. This retarder is formulated to enhance the rapid hardening of cement, with the mixture comprising 5 to 20% of the aforementioned acids and 50 to 85% of the alkali carbonate, facilitating quicker construction processes.
Career Highlights
Throughout his career, Nakagawa has worked with prominent organizations such as Denki Kagaku Kogyo K.K. and the Japanese National Railways. His expertise has been instrumental in advancing concrete technology and improving construction practices in Japan.
Collaborations
In his journey as an inventor, Nakagawa has collaborated with notable individuals, including Kenkiti Hirano and Yoshiharu Watanabe. These partnerships have driven innovation, fostering a culture of research and development in the concrete industry.
Conclusion
Koji Nakagawa's inventive spirit and dedication to enhancing concrete technology have solidified his status as a leading figure in the field. His latest patents showcase not only his technical prowess but also his commitment to innovation that meets modern construction needs. The impact of his work continues to resonate within the industry, paving the way for future advancements in concrete applications.