Colour purity improvement film for liquid crystal display device and liquid crystal display device having same
The present invention relates to a color purity improvement film (a color gamut enhancing film) that can improve the color purity of a liquid crystal display device, and a liquid crystal display device having the same. According to the present invention, a liquid crystal display device that blocks unnecessary wavelengths other than RGB wavelengths so as to improve color gamut and color purity may be provided by introducing a combination of dyes that absorb a particular Wavelength band to the inside of an adhesion layer or a coating layer of a as liquid crystal display device.
1. A liquid crystal display, comprising a backlight unit, and a liquid crystal panel,
wherein the backlight unit, the liquid crystal panel, or both of the backlight unit and the liquid crystal panel comprise a coating layer or an adhesive layer in configurations (a), (b), or both thereof:
(a) the liquid crystal panel sequentially comprises an upper polarizing plate, a first adhesive layer, a liquid crystal cell, a second adhesive layer, and a lower polarizing plate, and wherein the first adhesive layer, the second adhesive layer, or both of the first adhesive layer and the second adhesive layer comprise at least three types of dyes configured to absorb specific wavelength bands;
(b) the backlight unit sequentially comprises a dual brightness enhancement film (DBEF) or an upper diffusion plate, a horizontal prism sheet, a vertical prism sheet, a lower diffusion plate, a light guide plate, and a reflective plate, wherein the backlight unit has a coating layer on at least one position of one side or both sides of the dual brightness enhancement film or the upper diffusion plate, one side or both sides of the horizontal prism sheet, one side or both sides of the vertical prism sheet, one side or both sides of the lower diffusion plate, and one side of the reflective plate, and wherein the coating layer comprises the at least three types of dyes configured to absorb specific wavelength bands;
wherein the at least three types of dyes configured to absorb specific wavelength bands comprise a hydroxyl benzotriazole-based dye having a main absorption wavelength band of 380 to 420 nm, a pyrrole methine-based dye having a main absorption wavelength band of 480 to 510 nm, and a tetraaza porphyrin-based dye having a main absorption wavelength band of 560 to 610 nm.
2. The liquid crystal display of claim 1 , wherein the three dyes are included in a total amount of 0.01 wt % to 10 wt % based on a total weight of the coating layer or the adhesive layer.
3. The liquid crystal display of claim 1 , wherein the coating layer or the adhesive layer has a thickness of 2 to 100 μm.
4. The liquid crystal display of claim 1 , the first adhesive layer and/or the second adhesive layer further comprising a pressure-sensitive adhesive.
5. The liquid crystal display of claim 1 , the coating layer further comprising a binder resin.