Optical film, and preparation method

Abstract

A method for preparing optical film includes mixing PMMA mixture with solvent uniformly to form a wet film, heating said wet film to form an optical dried film, enabling to mix PMMA mixture in any ratio as per required property with solvent to form a mixed solution then carrying out heat treatment on mixed solution to obtain optical film.

Description

technical field [0001] The present invention relates to an optical film and a method for preparing the above optical film by mixing optical polymers, in particular to a PMMA (Polymethyl Methacrylate) optical film and a method for preparing the above PMMA optical film by solvent casting technology. Background technique [0002] The base materials of traditional optical films are generally based on triacetate (TAC: triacetate), PC (polycarbonate), and COP. The typical TAC film can be further used as a protective and supporting film for the optical film. Therefore, in addition to the required optical properties, the general TAC film must also have a certain strength, and have the characteristics of high temperature resistance and humidity resistance. To meet the use requirements of optical film, or to provide the effect of protecting the optical film composed of TAC film (refer to the following patents: JP4342202, TW499573, JP2000-324055, JP2001-235625, JP2003-195048, EP 1-2857...

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Problems solved by technology

[0004] The disadvantages of the above-mentioned prior art include: the TAC film has high water absorption and moisture permeability, so when it is used under high temperature and high humidity conditions, the optical properties of the optical film will be affected due to the deformation or stress of the film caused by the external environment, Even make the optical film unusable

And the b value of TAC is too high, which can be seen from the appearance, which is easy to cause visual obstruction

In addition, the water absorption and moisture permeability of COP film (such as Zeonor, Arton) are too small, the adhesion property is poor, and the material is too brittle

Although the microparticles in European Patent No. EP1154005A1 can reduce the surface roughness, the glass transition temperature of PET used in it is low (7)5, which cannot meet the heat resistance requirements of existing optical films

The PMMA / PC blended material property mentioned in Japanese Patent Laid-Open No. 7-56017 is too brittle, and the material thickness of PMMA / PEA blended is up to 500 micrometers (um), with respect to existing optical film, its applicability is very low. Insufficient, in view of the above-mentioned shortcomings, and in order to avoid material instability caused by melt blending or thermoplastic processing, and improve the heat resistance, moisture resistance and mechanical properties of the optical film, and effectively solve the stability problem of the optical film, this paper The invention provides an optical film and its manufacturing method that can solve the above-mentioned shortcomings

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