In a multi-layer structure of a cellulose acylate film, the averaged
degree of acylation of surface layers is controlled in the range of 0.5
to 2.8 by mixing several sorts of cellulose acylates having different
averaged degrees of acyation. One of the surface layers is formed on a
substrate by casting a solution containing cellulose acylate made of
cotton linter. Lubricant particles are added to a solution for the
surface layers, and emission compounds to a solution for the inner
layers. The obtained cellulose acylate film is excellent in adhesive
property to the hydrophobic material without saponification, and
adequately used for the polarizing filter, an optical compensation sheet,
and liquid crystal display.