Zao and his wife pursued their own careers, their son having stayed in China with Zao's parents. In the mid-1950s, they were divorced. In 1957, Zao decided to visit the United States where his younger brother Chao Wu-Wai was living in Montclair, New Jersey, close to the art scene of New York City. He wanted to learn more about "pop art". While in the US, he painted seven canvases at his brother's house. There are relatively few items dating from that year (1957). Years later, the largest canvas was given by his brother, Chao Wu-Wai, to the Detroit Institute of Arts.