A kind of azo dye DYE-R was got by coupling reaction of diazonium salt of Congo red with 2-amino-8-naphthol-6-sulfonic acd. The colorful polaroid films were obtained by extension,racking and desiccation after mixing DYE-R with polyvinyl alcohol(PVAL).

• 以刚果红的重氮化物和2-氨基-8-萘酚-6-磺酸偶合得到三偶氮染料DYE-R,再与聚乙烯醇(PVAL)水溶液混合后经流延、拉伸、干燥处理后得到彩色偏光膜。