| 摘要 |
PURPOSE:To obtain a polarizing plate having superior heat resistance and moisture resistance by sticking a heat resistant protective film having low moisture permeability to the surface of a polarizing PVA film provided with polarizing performance by the adsorption and orientation of a dichroic dye and with heat resistance by specified heat treatment. CONSTITUTION:A dichroic dye such as Direct Black 17 is adsorbed on a polyvinyl alcohol film, and the dyed film is uniaxially stretched about 3-4 times with hot air. The stretched film is heat treated under tension so that it has <=1% rate of shrinkage in a direction perpendicular to the stretching axis after heating at 100 deg.C for 30min. A transparent protective film is stuck to the surface of the resulting polarizing PVA film provided with heat resistance to obtain the desired polarizing plate. The protective film has <=55gr/m<2>hr moisture permeability at 80 deg.C and 95% RH, -0.3-0% rate of dimensional change after heating at 100 deg.C for 30min and <=100nm retardation value. |
