Eiichi HOSOKAWA was born in Nakagawara-cho, Tsuna-gun (now Sumoto-shi), Awaji Island, Hyogo Prefecture, Japan in 1889. At that time, there were many water mills for grinding flour, and he used to play around them as a child. After graduating from a junior high school under the old system of education, Eiichi was troubled about his future career path, but he was encouraged by his grandfather's words, "If only you would study, no one would steal from you," so he entered the mechanical department of Nagoya Technical School (now Nagoya Institute of Technology).
One year after the company was founded, Eiichi married Gohei Osame's sister, Hatsu. Gohei Osame, who became Eiichi's brother-in-law, was an expert in the construction of sulphuric acid manufacturing equipment and founded the Osame Sulphuric Acid Industrial Office in 1926 and succeeded in domestically producing the vanadium catalyst needed to produce sulfuric acid. Furthermore, the dust collection equipment required for the production of sulphuric acid was based on the same principle as that of electrostatic painting equipment, so an electric painting machine was developed and the painting process was automated. This business has been passed on to the present company, Osame Industry Co. On the other hand, the development of catalysts also led to significant business, and the Osame Sulfuric Acid Industrial Office went through several changes and is now Nippon Shokubai Co.

Eiichi's company did not develop smoothly either. Two typhoons (Typhoon Muroto and Typhoon Jane) flooded the factory, and in 1927 a fire broke out in the neighbourhood, destroying the factory and his house. He was very grateful to his neighbours for lending him furniture and bedding, and to his business partner, MOMOTANI JUNTENKAN, for clearing up the ruins of the fire.

The MOMOTANI JUNTENKAN kindly allowed us to rent an adjoining plot of land (2-30 Takao-cho, Minato-ku, Osaka, now Ichioka 2-chome), where we were able to build a new factory. This continued to be the main manufacturing site until the present Osaka factory (Hirakata, Osaka) was built.

Eiichi was an engineer at heart and had little interest in business. This led his brother Akihiko to ask Masuo, who was then working for Takeda Pharmaceutical Company Limited, to join him in order to modernise the company.