Teijiro Inoue created corrugated board after a great deal of effort as well as trial and error. He is the person who came up with the name "danboru" for corrugated board, which is now a household term. After experiencing many difficulties, he developed his own management philosophy, called "Kintoma."

In short, "Kintoma," coined by Teijiro, indicates an invariable principle of business. In line with this principle, he tells businesspeople that once they have acquired "iron will," "money," "sincerity" and "timing" they should hold onto these qualities for life. He emphasizes that they should grasp business opportunities in a timely manner and value personnel, equipment, capital, and sincerity when managing their business. A modern translation of "Kintoma" would be that "businesspeople, having money and a strong will, must engage in the management of their business with sincerity while placing an emphasis on personnel, time, and equipment." Since the foundation of Rengo, the "Kintoma" philosophy has been handed down from generation to generation as a guiding principle and code of conduct.