Printed 3D coloured objects: 3D ink-jet prints colour properties and colour stability

3D ink-jet printing is an additive, powder-based rapid prototyping (RP) process. The 3D printing process described in this overview has been developed by ZCorporation and is based on an ink-jet printing technique. The 3D computer models, created by 3D scanning or in 3D CAD modelling software, are built layer by layer from the basic materials of powder and binders. Due to the basic build principle, it is currently the only RP process capable of printing in “full” colour, and uses clear binder with CMY or CMYK coloured binders. The emerging areas of this 3D printing application has opened up opportunities for expressing new and creative ideas, but at the same time, has presented new challenges for material research. These issues include: the colour properties of 3D prints, the effect of materials and process properties on the achieved colour, 3D printed surface characteristics and methodologies for colour measurement. Furthermore, the question of the colour permanence and stability of 3D prints is a growing issue and considers which methods could be applied to study permanence and how long the prints will last.