Cellulose acylate film, method for producing same, polarizer and liquid crystal display device
AssigneeFUJIFILM Corporation
InventorsJun TAKEDA, Yoji ITO
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Abstract
A cellulose acylate film, which comprises a cellulose acylate having a total degree of substitution of from 2.1 to 2.3 and a non-phosphate compound, which satisfies the following formulae (1) and (2), and which has a thickness of from 10 μm to 45 μm, has desired optical expressibility, small internal haze, and curling resistance when used in polarizer, and, when mounted in liquid crystal display devices, is capable of significantly solving the problem of color shift and corner unevenness on the display panel: 40 nm≦Re(550)≦60 nm (1) 100 nm≦Rth(550)≦300 nm (2)
Claims20
A cellulose acylate film, which comprises a cellulose acylate having a total degree of substitution of from 2.1 to 2.3 and a non-phosphate compound, which satisfies the following formulae (1) and (2), and which has a thickness of from 10 μm to 45 μm:
- 40 nm≦Re(550)≦60 nm (1)
- wherein Re(550) means the in-plane retardation of the film at a wavelength of 550 nm,
- 100 nm≦Re(550)≦300 nm (2)
- wherein Rth(550) means the thickness-direction retardation of the film at a wavelength of 550 nm.
A polarizer comprising a polarizing element and a cellulose acylate film on at least one side of the polarizing element, wherein the cellulose acylate film comprises a cellulose acylate having a total degree of substitution of from 2.1 to 2.3 and a non-phosphate compound, which satisfies the following formulae (1) and (2), and which has a thickness of from 10 μm to 45 μm:
- 40 nm≦Re(550)≦60 nm (1)
- wherein Re(550) means the in-plane retardation of the film at a wavelength of 550 nm,
- 100 nm≦Re(550)≦300 nm (2)
- wherein Rth(550) means the thickness-direction retardation of the film at a wavelength of 550 nm.
A liquid crystal display device comprising a polarizer comprising a polarizing element and a cellulose acylate film on at least one side of the polarizing element, wherein the cellulose acylate film comprises a cellulose acylate having a total degree of substitution of from 2.1 to 2.3 and a non-phosphate compound, which satisfies the following formulae (1) and (2), and which has a thickness of from 10 μm to 45 μm:
- 40 nm≦Re(550)≦60 nm (1)
- wherein Re(550) means the in-plane retardation of the film at a wavelength of 550 nm,
- 100 nm≦Re(550)≦300 nm (2)
- wherein Rth(550) means the thickness-direction retardation of the film at a wavelength of 550 nm.
Dependencies are inferred from the claim text.