| abstract |
A composition for preparing an optical film, comprising a tetracarboxylic acid dianhydride represented by Chemical Formula 1, a first diamine represented by Chemical Formula 2, and a second diamine represented by Chemical Formula 3, wherein an amount of the second diamine represented by Chemical Formula 3 is equal to or less than 30 mol % based on the total amount of the first and second diamines: n n n n n n n n n n n n wherein, R 1 to R 5 , n1 to n3 are defined in the specification. |