As discussed previously in section 3 of this chapter, the Kariya Plant Rubber Product Manufacturing Department was renamed the Kariya Plant Rubber Section in February 1942. The rubber industry was quickly placed under control, and raw rubber became increasingly difficult to obtain as the war situation deteriorated.

It was under these circumstances that the Ministry of Commerce and Industry recommended to Toyota Motor Co., Ltd. that the rubber manufacturing department be spun off and consolidated with other rubber companies. Toyota Motor's rubber manufacturing department's facilities, personnel, and new rubber use volume did not meet the standards under the governmental directive for the integration of industry, and as a result, it was subject to reorganization.

At around the same time, an inquiry was received from Takashimaya Iida1, a trading company, concerning management participation by Toyota Motor Co., Ltd. in Kokka Kogyo, a rubber company in which it had invested. Following consideration of the matter, Toyota Motor Co., Ltd. decided to acquire the shares of Kokka Kogyo and integrate the company with the Kariya Plant Rubber Section. This new rubber business with Kokka Kogyo allowed the idle Kikui Shokufu Plant and its personnel to be used.

The Kariya Plant Rubber Section was integrated with Kokka Kogyo in May 1943 and with its manufacturing became the Kokka Kogyo Nagoya Plant.2 After the war, the Rubber Section was spun off from Kokka Kogyo in June 1949 and became Nagoya Rubber Co., Ltd. Today the company is known as Toyoda Gosei Co., Ltd.