| 초록 |
Organic-inorganic hybrid composite coating can be widely used in display such as optical film, lenses, camera filter due to flexibility, high hardness, chemical durability and optical transparency. The organic film has been successfully substituted the glass in display as a transparent optical material since the glass has limitation to realize the ability to bend and fold. The disadvantages of surface hardness is widely known to be overcomed by addition of inorganic nanoparticles to the polymer to make the hybrid composite coating. The selection of proper nano particles for hybrid coating in type, size, contents, and its surface treatment is based on the effects of silica on their physical, mechanical, and optical properties of the composite. The polyimide film is clear but slightly yellowish, which is disadvantageous in application. By incorporating silica nanoparticles in the organic materials, it is found to obtain organic films with not only increased hardness but also change of color tone, without decreasing the transmittance and flexural properties of the organic material. It is necessary to study dispersibility of the sol and flexibility, hardness, change of color tone and folding and bending test of the hybrid coating film according to the silica particle size. The hybrid coating film has a decreasing value of b * in the color coordinates of Lab, where the yellowish tone of the bare film is reduced by addition of silica particles. The change of color is increasing as the silica particles increase from 10 to 30nm. When the silica nanoparticles used in the film coating sol increased from 10 to 30 nm, the transmittance and flexibility decreased by 6%, 0.005 and the hardness increased from 7H to 9H. As a result of the folding and bending test, the silica particles used in the film coating solution were unbroken at 10 and 20 nm and broke at 30 nm. |
