Performance of Starch Based Flexographic Inks and Biodegradability

Abstract

This research was the preparation of an alternative printing ink to benefit the environment due to biodegradability and non-toxic substance. Tapioca starch blending with water soluble polymer or Polyvinylpyrrolidone (PVP) was also used as binder in a water-based printing ink of flexography. In addition, PVP was necessary blended into the tapioca starch to fulfill some ink properties involving ink flow and ink-film performance. In experiment, the tapioca starch was blended with PVP using overhead stirrer at different ratios of 1:1, 1:2, and 2:1. The tapioca starch-PVP blends and their inks were measured their viscosity, which had shear thinning behavior as shown in a common flexo ink. Pigment wetting and dispersion of copper phthalocyanine blue to the starch based vehicle showed good result; approximate of 2.5 micrometer was a fine size, which was appropriated to flexographic printing. Printing performance of this starch based on printing inks such as optical density, rub resistance, and lightfastness was tested, and they had properties as same as those of the water based flexo ink. The starch based ink had excellent water resistance: it was better than that of the common water based flexo ink. Biodegradability of the starch based inks for 1 month buried in soil was also studied by measuring weight reduction, CO2 emission content via Gas Chromatography technique, and chemical structure analysis using Fourier Transform Infrared Spectrometer.