Resin composition and optical films formed by using the same

A resin composition comprising:

• (A) at least one copolymer comprising more than one unit selected from the group consisting of
• (1) a (meth)acrylate-based unit comprising one or more (meth)acrylate-based derivatives, and
• (2) a styrene-based unit comprising one or more styrene-based derivatives;
• and
• (B) an aromatic based resin having a chain having the hydroxy group containing portion and aromatic moiety,
• wherein the aromatic based resin includes 5 to 10,000 at least one type of units represented by Formula 1:
• wherein X is a divalent group comprising at least one benzene cycle and R is a straight- or branched-chained alkylene group having 1 to 6 carbon atoms, and
• wherein the copolymer further comprises a cyclic based unit comprising cyclic moiety.