POLYAMIC ACID DERIVATIVE HAVING IMIDE RING-CONTAINING SIDE CHAIN FOR LIQUID CRYSTAL ALIGNMENT LAYER

摘要

PURPOSE: A polyamic acid derivative having an imide ring-containing side chain for a liquid crystal alignment layer and a monomer for the preparation of the polyamic acid derivative are provided, to improve heat resistance, surface strength, transparency and vertical alignment of liquid crystal. CONSTITUTION: The polyamic acid derivative is represented by the formula 1, wherein n is an integer of 1-300 and m is an integer of 1-30. Preferably the polyamic acid derivative has an intrinsic viscosity of 0.3-1.5 dL/g, a molecular weight of 10,000-150,000 g/mol, a glass transition temperature of 230-400 deg.C and a pretilt angle of 85-89.9 degree, is soluble in a solvent selected from the group consisting of dimethyl acetamide, dimethyl formamide, N-methyl-2-pyrrolidone, tetrahydrofuran, chloroform, acetone, ethyl acetate and γ -butyrolactone, and has an imidation temperature of 200-300 deg.C. The monomer is represented by the formula 2, wherein m is an integer of 1-30.