Abstract: A method of making a polarizer and a polarizing sheet is disclosed. The method of making a polarizer comprises providing a polyvinyl alcohol (PVA) film; dipping the PVA film into a first solution to perform a pre-treatment, wherein the first solution contains a carboxylic acid having at least two carboxyl groups or a derivative thereof and a catalyst catalyzing the reaction between the carboxylic acid and the surface of the PVA film; dipping the pretreated PVA film into a dye solution to perform a dyeing; dipping the dyed PVA film into a second solution while stretching the PVA film, wherein the second solution contains boric acid; and drying the stretched PVA film to form a polarizer.

Abstract: A method of making a polarizer includes providing a polyvinyl alcohol (PVA) film; dipping the PVA film into a dye solution for dyeing; dipping the PVA film into a first solution for pre-treatment; and dipping the pretreated PVA film into a second solution while stretching the PVA film. The first solution contains dicarboxylic acid and a catalyst for catalyzing the reaction between the dicarboxylic acid and the surface of the PVA film, and does not contain boric acid. The second solution contains boric acid.