Light-diffusing film and production method therefor, and display device

Abstract

The present invention addresses the problem of preparing a light-diffusing film that has a haze of at least 50%, an inner haze of at most 15%, and a total light transmittance of at least 90%. This light-diffusing film may be configured such that the light transmitted therethrough has a chromaticity b* of 10 or less and a chromaticity a* of 2 or less. The light-diffusing film includes a transparentfilm and a light-diffusing layer formed on at least one side of the transparent film, and the light-diffusing layer may have a 60 DEG-gloss value of 10% or less. The surface of the light-diffusing layer may have an arithmetic average surface roughness Ra of 0.3 mum or more. The average interval Sm between the irregularities on the surface of the light-diffusing layer may be 100 mum or less. The light-diffusing layer can be a cured material of a curable compound that contains at least one type of a polymer component and at least one type of a cured resin precursor component. This light-diffusing film exhibits high degrees of light diffuseness and luminance.

Description

technical field [0001] The present invention relates to a light-diffusing film capable of isotropically diffusing light, which can be used in various display devices such as organic electroluminescent (EL) displays and liquid crystal display (LCD) devices, and a method for producing the same, as well as a device comprising the above-mentioned film. display device. Background technique [0002] Light-diffusing films have been widely used in lighting covers, image display devices (for example, organic EL displays, liquid crystal display devices, etc.), and the like. As the optical characteristics required for such a light-diffusing film, in addition to the light-diffusing properties for improving anti-glare properties due to having a high haze, the following characteristics can also be listed: High transparency (total light transmittance) , and not yellow or reddish color, but neutral white light is provided to the viewing side to improve visibility. Furthermore, in an image...

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Problems solved by technology

[0006] However, for the light-diffusing film in which the filler is dispersed, the greater the difference in refractive index between the matrix material constituting the light-diffusing layer and the dispersed filler, the higher the haze value and the higher the light diffusibility. increase, the light on the short-wavelength side scatters toward a wide angle, so when the display device is viewed from the front, it looks yellowish and dim, and the visibility decreases

In addition, since backscattering tends to occur, transparency is also reduced

Furthermore, light diffusivity is also low, and visibility cannot be sufficiently improved even in an organic EL display in which color unevenness occurs.

In this way, in the conventional technique of increasing the haze by dispersing particles having different refractive indices in a transparent resin, light diffusivity and visibility are in a trade-off relationship, and it is difficult to achieve both.

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