Cellulose acylate film

A cellulose derivative dope composition comprising:

• a) a cellulose derivative that satisfies the degrees of substitution below
• 2.5≦X+Y+Z≦3.0
• 0<X+Y<3.0
• 0<Z<3.0
• wherein X denotes the degree of substitution by acetyl, Y denotes the total of the degrees of substitution by acyl groups other than acetyl, and Z denotes the degree of substitution by a group represented by Formula (1) below
• -(L1)m(L2)SiRnQ3−n (1)
• wherein L1 denotes a divalent connecting group that can form a bond with an oxygen atom originating from a cellulose hydroxyl group, L2 denotes a divalent connecting group, R denotes an alkyl group, an aryl group, an alkenyl group, an alkynyl group, or a heterocyclic group, Q denotes a halogen atom, an alkoxy group, an aryloxy group, an alkenyloxy group, an alkynyloxy group, a heterocyclic oxy group, or an acyloxy group, m denotes 0 or 1, and n denotes 0, 1, or 2;
• b) a hydrolyzable and polycondensable reactive metal compound;
• c) a metal chelate compound and/or an organotransition metal compound for hydrolysis and polycondensation of the reactive metal compound;
• and
• d) a solvent.