Advanced Functional Materials, Vol.25, No.47, 7375-7380, 2015
Sol-Gel Assisted Inkjet Hologram Patterning
Hereby, it is presented for the first time a method of producing holographic text and images using inkjet printing. For this purpose, colorless TiO2 ink with a high refractive index is used and deposited on top of exposed poly(ethylene terephthalate)-based microembossed paper by an inkjet printer. Nanoscale coating the paper containing printed text or graphics with transparent polymers or lacquers provides an optical effect of selective preservation of the holographic pattern. The resulting image is preserved only at the site of the colorless ink with a high refractive index from an inkjet printer, allowing to quickly generate any image with a holographic effect. Achieving these results has succeeded through the use of a colloidal dispersion of nanocrystalline titania with a refractive index of 1.75 +/- 0.08 in the entire visible range, which meets inkjet rheological requirements. It is shown that the diffraction effect and optical transparency in the visible region are fully preserved. For the first time, it is demonstrated the importance of chemically prepared nanomaterials and nanostructures for an application in the field of holography.