Polarizing element or polarizing plate for display device with blue light emitting element

Abstract

[Problem] The present invention relates to a polarizing element and a polarizing plate, which can improve contrast and enhance color display characteristics in an organic electroluminescent display device. [Solution] A substrate having a polarizing function and containing an azo compound is controlled such that the substrate alone has a transmittance of 45% to 60%, the average transmittance of 440-nm to 500-nm wavelengths for one substrate is 50% or more, and the average transmittance of 550-nm to 650-nm wavelengths as obtained by measuring two substrates arranged such that the absorption axis directions thereof are orthogonal to one another is 10% or less.

Description

technical field

[0001] The present invention relates to a polarizing element or a polarizing plate for organic electroluminescence. Background technique

[0002] A polarizing element is generally produced by adsorbing and aligning iodine as a dichroic dye or a dichroic dye on a polyvinyl alcohol resin film. On at least one side of the polarizing element, a protective film made of triacetyl cellulose or the like is attached via an adhesive layer to form a polarizing plate, which is used in a liquid crystal display device or the like. A polarizing plate using iodine as a dichroic dye is called an iodine-based polarizing plate, and a polarizing plate using a dichroic dye as a dichroic dye is called a dye-based polarizing plate. Among them, dye-based polarizers are characterized by high heat resistance, high humidity and heat durability, high stability, and high color selectivity by mixing. On the other hand, they have the following problems: When comparing polarizing plates, ...

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