New holographic polymeric composition based on plexiglass, polyvinyl butyral, and phenanthrenquinone

The newly developed Plexiglas films containing polyvinyl butyral resins and phenanthrenequinone molecules as photosensitive dopant, which are proposed for the practical application as interlayer of laminated safety glass, are shown for the first time. The injection of the phenanthrenequinone–poly(methyl methacrylate) into the polyvinyl butyral protective interlayer provides a homogenous distribution of the recording holographic medium in the layer and allows fixing the entire surface grating in the laminated glass. In addition, the original properties of polyvinyl butyral as a connecting material were preserved during manufacturing of the laminated glass. This allows a recording of holographic structures directly after baking of the laminated glass, thus reducing the destruction of the gratings due to the elevated temperatures. The diffractive structures in phenanthrenequinone–poly(methyl methacrylate)–polyvinyl butyral polymeric layers with thicknesses of hundreds of microns are sealed between two panels of glass (so-called laminated glass) and are generated by illumination with an Argon-laser of 514 nm. Efficiently fixed and long-term stable holographic gratings recorded in the phenanthrenequinone–poly(methyl methacrylate)–polyvinyl butyral layer enable to produce transparent laminated glass with inserted diffractive elements, which can be used e.g. for Head-up Displays in automobile windshields or as holographic light concentrators for solar cells.