Abstract
The domain structure immediately after heat treatment was investigated by the nematic liquid crystal method. Just below T c very fine domain patterns narrower than 0.5 µm in width were observed. With time, the domain pattern gradually becomes coarse. Mean domain width grows in proportion to the time elapsed since the moment of T c, and the rate of growth is almost independent of temperature. The evolution of the domain pattern is caused by the development of large domains accompanied by the vanishing of small domains, as well as by the contraction of crooked boundaries.