| 초록 |
We prepare antireflection film by coating of poly(methyl methacrylate) in chloroform with a small amount of nonsolvent of alkanes. We used poly(methyl methacrylate), chloroform as solvent and hydrocarbon Alkanes as nonsolvent. When boiling point of nonsolvent is higher than that of solvent, dense skin layer forms due to active solvent evaporation during spin coating and nonsolvent content in liquid layer below dense skin layer increases due to boiling point difference. Nonsolvent induces phase separation and leaves pores after complete evaporation of solvent and nonsolvent. This process is a kind of dry phase inversion process through which gas separation membranes have been fabricated. Dissimilarly to conventional membrane, film structure could be scaled down to nanometer scale. This two layers of dense skin layer and porous inner layer act as excellent Antireflection film when coated on glass substrate. Simply by one-step procedure of spin coating, high transmittance over 99% was easily achieved. Also dense skin layer is expected to act as protective layer and further coatings such as protective layer and multilayer deposition for optical thin film are possible, which was not possible on previously reported AR layer of rough surface as porous layer. |
