Patent ID: 8895682
Filing Date: 2014-11-25
Classification: C08F,G02B

Abstract:
1. A thermoplastic acrylic resin of a copolymer comprising 10 to 70% by weight of a repeating unit derived from a methacrylate monomer represented by the following formula (1), 5 to 40% by weight of a repeating unit derived from a vinyl aromatic monomer represented by the following formula (2), and 20 to 50% by weight of a repeating unit of a cyclic acid anhydride represented by the following formula (3), wherein a molar ratio (B/A) is within the range of more than 1 to not more than 10, wherein (A) is a content of the repeating unit of the vinyl aromatic monomer and (B) is a content of the repeating unit of the cyclic acid anhydride, and the total amount of remaining monomers to 100 parts by weight of the copolymer is not more than 0.5 part by weight: wherein R 1 represents hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 5 to 12 carbon atoms; wherein R 2 and R 3 may be the same or different from each other, and represent hydrogen atom, a halogen group, a hydroxyl group, an alkoxyl group having 1 to 12 carbon atoms, a nitro group, a linear or branched alkyl group having 1 to 12 carbon atoms, and l is an integer of 1 to 3; wherein R 5 to R 6 may be the same or different from each other, and represent hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, wherein the thermoplastic acrylic resin has the following optical property (i): (i) an absolute value of a photoelastic coefficient (C) being less than 2.5×10