Conversation so far:
what was Jikken Kobo?
an artistic group established for multidisciplinary collaboration on mixed-media projects, who sought to avoid Japanese artistic tradition.
what kind of projects did they produce?
During this period he wrote Saegirarenai Kyusoku I ("Uninterrupted Rest I", 1952: a piano work, without a regular rhythmic pulse or barlines).
what else did he produce?
by 1955 Takemitsu had begun to use electronic tape-recording techniques in such works as Relief Statique (1955) and Vocalism A*I (1956).
was he working on his own or did he get help from others?
Takemitsu also studied in the early 1950s with the composer Fumio Hayasaka, perhaps best known for the scores he wrote for films.

Question: What films did he write for?
Self-contained rewrite: What films did Tōru Takemitsu write for?