South Korean President Chun Doo Hwan flew home today after a three-day visit to Tokyo that affirmed friendship between his country and Japan but brought little substantive progress in solving differences between them.

A 12-point communique issued this morning declared that the visit "opens a new chapter" in Japanese-South Korean relations. Technology transfer and status of Korean residents in Japan, the two major sticking points, will be the subject of further discussion, it said.

Chun was the first Korean head of state to make an official visit to Japan, which ruled Korea as a colony from 1910 to 1945. Officials in both governments have expressed hope that the visit will help erase suspicions between the two lingering from that period.

The high point of the visit came at a state dinner Thursday night, when Japan's 83-year-old Emperor Hirohito expressed regret for the "unfortunate past" between the two countries. Securing such a statement was politically important for Chun at home.

The communique said Japan would support South Korea's proposal that both it and communist North Korea receive full membership in the United Nations. Japan previously had taken no formal position on the idea. The two Korean governments now have observer status there.

North Korea, however, has rejected the idea, saying that it would perpetuate the division of the peninsula.

The communique said that Japan supports South Korea's position that reunification of Korea should be settled "basically through direct dialogue between the authorities of North and South." It also said that Japanese Prime Minister Yasuhiro Nakasone "expressed his high regard for the defense efforts" of South Korea, which he said helped keep peace there.

North Korea has stressed, as the key to peaceful reunification, talks with the United States to secure the withdrawal of the 40,000 troops it maintains in South Korea.

During ministerial-level talks here yesterday, South Korea repeatedly pressed for concessions from its much wealthier neighbor. Japan, however, deferred most of the requests, stressing instead the symbolic qualities of Chun's visit.

Concerning technology transfers, which South Korea says are needed to correct its longstanding trade imbalance with Japan, the two countries agreed to begin negotiating a science and technology cooperation agreement and to promote private sector investment.

The communique said Japan will "continue its efforts" to improve the legal status and treatment of 670,000 Korean nationals here, who form Japan's only significant minority group. But the statement gave no details on what steps the government would take.

South Korean officials, however, maintained before Chun's departure that they were satisfied with Japan's responses.

"Specific issues standing between Korea and Japan would be settled once the climate of mutual confidence is established," said Hong Soon Young, the president's secretary for political affairs.

Chun, meanwhile, did not discuss the bilateral issues during three meetings with Nakasone, according to officials on both sides. Instead, he stuck to broad principles of relations between the two countries and security on the Korean peninsula.

At his final meeting with Nakasone at a lunch at the prime minister's residence today, the conversation covered such nonpolitical subjects as the intoxicating powers of sake and Chun's plan to study Japanese, according to Japanese officials.

Contrary to the Japanese government's fears beforehand, there was no street violence or attempt to assassinate Chun during the visit. With thousands of police blocking off streets and checking cars, demonstrations were small and peaceful.