Polarization film null formula (i) or is shown with formula (ii) polyazo chemical compound or that salt which possess

摘要

PROBLEM TO BE SOLVED: To provide a polarizing membrane improving a polarization degree and having an excellent light resistance, that is the decrease of absorbance is low even the polarizing membrane is exposed to a large quantity of light for a long period of time under the condition of a high temperature, and to provide a compound and its salt suitable for a dye for polarizing membrane obtaining the polarizing membrane.;SOLUTION: The polarizing membrane comprises the polyazo compound or its salt represented by formula (I) or (II), the dye for polarizing membrane containing the same and a base material for polarizing membrane (wherein Me represents copper, nickel, zinc or iron; A represents a naphthyl group optionally containing 1-3 sulfonic acid group and an alkyl or alkoxy group; R¹ and R² represent each independently a hydrogen atom, alkyl group or alkoxy group; R³ represents an amino group or hydroxy group).;COPYRIGHT: (C)2005,JPO&NCIPI