With the conclusion of the San Francisco Peace Treaty in September 1951, Japan regained a position as part of international society. In July of the following year, controls on consumption of petroleum products were released after 14 years.
Also, in May 1952 foreign currency was allocated to gasoline imports as well, and Idemitsu imported 5,000 kiloliters of gasoline (with an octane rating of 75 and an actual value of 77.2) from the U.S. West Coast, aboard the second-generation Nissho Maru, which had been commissioned in the previous year. It sold this gasoline under the Apollo brand name.
Importing High-Octane Gasoline from the United States

The second-generation Nissho Maru sails under the Golden Gate Bridge
At that time, the octane rating of gasoline sold in Japan had been only about 60. Under these conditions, the newly introduced Apollo gasoline earned a reputation for increasing a vehicle's horsepower, making it possible to drive over the mountains in the Hakone region of Japan without stalling.
With the appearance of Apollo gasoline, the quality of gasoline in Japan improved, as each oil refining company progressively introduced oil reforming and cracking units.

An Idemitsu service station selling the popular high-octane gasoline
- Idemitsu Shokai Founded in Moji
- Overseas Branches Closed, Repatriation Begins
- Importing High-Octane Gasoline from the United States
- The Nissho Maru Incident: Challenging the Dominance of the Major Oil Firms
- Construction of Mammoth Tankers
- Completion of the Tokuyama Refinery
- Chiba Refinery Completed/Idemitsu Withdraws from the PAJ
- Idemitsu Enters the Oil Exploration and Production
- The First Oil Crisis and Advancing Overseas
- Specific Petroleum Law Abolished
- The Establishment of Idemitsu Credit and Development of the Credit-Card Business
- Outbreak of the Gulf War
- Introduction of Low-Benzene Gasoline