Polyvinyl alcohol type polarization film, polyvinyl alcohol type polarization plate and colored LCD projector with the polarization plate

本发明涉及一种含有自由酸形式的由通式(1)表示的水溶性染料或其铜络盐的聚乙烯醇型偏振膜或板。所说偏振板具有优越的偏振性能和耐久性，当通式(1)中的B为苯甲酰氨基并且所述水溶性染料具有大于等于520nm且小于580nm的最大吸收波长(λmax)时，所说偏振板适用于液晶投影仪的绿色通道。∴ This invention relates to a polyvinyl alcohol type polarizing film or plate which comprises a water-soluble dye having the formula (1) in a free acid form or a copper complex salt thereof. The said polarizing plate has excellent polarizing performance capability and durability, and is suitably used for the green channel of a liquid crystal projector when B in formula (1) is a benzoylamino group and the water-soluble dye has awave length for maximum absorption ( lambda max) of 520 nm or more and less than 580nm.