Single-process fabrication of antireflective acrylic hard coating via surface segregation of porous silica nanoparticles

Abstract

A new type of antireflective (AR) acrylic hard coating consisting of a surface-segregated single layer of silica nanoparticles and acrylic polymer matrix is proposed that exhibits good mechanical stability and AR capability. In addition, the polymer hard coating can be obtained by a single coating process. Porous silica particles 100 nm in diameter with surfaces modified by hexamethyl disilazane (HMDS) undergo spontaneous segregation at the air interface of the acrylic monomer film. The monolayer of porous silica particles can serve as an AR surface; a reflectance of 2.7% at 550 nm and a pencil hardness > H are achieved. The great advantage of the present approach is that a hard coating with AR capability can be obtained from an acrylic monomer solution containing porous silica nanoparticles via a presently available general polymer coating process. The present approach to an AR hard coating offers a much easier and simpler way than the conventional ones, which require multi-step coating or nanolithography.