Looking at the stringent requirements of nano-sized ceramic inks for ink jet printers, Jyoti Ceramic has introduced narrow fraction size micro milling beads. These specially formulated ceria-stabilized zirconia beads are marketed under the brand name Zirconox, and are featured at Stand 7-343.
In recent years, the use of digital ceramic tile decoration, digital decoration systems and technology has grown greatly. At the same time, the technology used for manufacturing special nano-inks used in ink-jet printing for digital ceramic tile decoration has evolved rapidly. The requirements of nano-inks used for reproducing high-resolution images on ceramic articles are rather severe. The quality of digitally printed images on ceramic depends greatly on control and optimization of ink properties. And ink-jet printer technology imposes many constraints on inks that can be used. These inks must exhibit the correct narrow particle size pigment range, color strength, suspension stability for long periods, surface tension and low viscosity. Ultra-fine particles of pigments tend to have a negative effect on color quality and dispersion, thus resulting in low-quality printing. These nano-inks should be free from print head nozzle clogging and dispersion instability. To successfully produce very narrow-defined particle size pigments it becomes essential to use the correct milling media for optimized results.
Zirconox micro milling beads achieve all the above desired suspension properties for inkjet printing inks. Advantages include:
Pigment Particle Size Reduction in Reduced Time
Zirconox micro beads have a density of 6.20 gm/cc and a hardness of 1200 on Vickers scale, which makes them the most cost-effective milling media for speedy dispersion and micro fine milling of pigments. With a narrow fraction bead size (i.e. Ø 0.2 to 0.4 mm) and a bulk density of 4.0 kg/L, the desired particle size of d99 <1µm is achieved in shorter time. This reduction in time to achieve narrow particle size pigment results in improved color strength and other physical properties of the milled suspension.
Easy Changing Of Color Suspension With Reduced Wash Time
Even after continuous use it has been proven that 90-95% of Zirconox micro beads maintain their sphericity >0.96, a satin-smooth glossy surface finish, and remain free from pinholes or cracks. Due to these characteristics, milled pigments do not adhere to the beads. Moreover, as the beads remain free from pinholes or cracks, pigments do not get entrapped, thus resulting in quick, easy washing. This reduced wash time after the milling process or when changing from one color pigment to another saves the cost of expensive solvents.
Negligible Wear of Expensive Mill Parts
Nano-inks are mostly milled with relatively low viscosities (< 50 mPas). Generally, milling pigments with such low viscosity increases the chances of expensive mill parts wearing off. Zirconox micro beads are unique because due to their dense homogenous internal microstructure, their sphericity and glossy satin smooth surface finish increase considerably as milling process time increases. Thus these micro beads with a smoother, glossier surface finish are very gentle on expensive mill parts.
