Zhang, an artist born in 1938, is famous for his flower-and-bird painting as well as seal cutting. He started making portrait seals in the 1990s and developed the craft into a unique art form. Portrait seals were first seen in ancient China's Qing Dynasty (1644-1911), when they were like line drawing tapestry portrait. Modern portrait seals have absorbed elements of traditional Chinese painting, oil painting, cartoon comics and other kinds of painting.