Inkjet printing has revolutionised the global ceramic tile decoration industry over a relatively short time. This is an amazing achievement for an industry that for many years traditionally produced either plain or unsophisticated patterned tiles using screen printing and had little use for computers. The conversion of production lines to digital decoration is set to continue as it offers such great economic benefits, but what are the next challenges with ceramic tile decoration and where else can digital inkjet technology provide benefits?Increased colour space
One of Xaar’s main focuses is to look at what can be done to improve the colour space of ceramics inks. One challenge during the uptake in digital inkjet decoration was to develop a new type of digital ink. Previously with screen printing, colour was applied in high volume pastes with large pigment particle sizes. However with drop-on-demand inkjet printheads, the colour is delivered in a small drop of liquid where the pigment particle size is smaller. The reduction in the particle size affects the colour space that can be achieved with digital inks, and in some cases they lose their ability to reflect light completely.
Xaar identified two methods that can improve the final colour achieved by digital printing. Firstly, increasing the amount of ink put down by the printing process, and secondly, increasing the pigment particle size. Both of these factors would further improve the colour gamut of the digital inks. Big effects
Xaar has identified the opportunity to digitally add relief or texture to tiles giving them a profile just like the materials they are trying to imitate. The current technique for achieving relief on a tile is to use a mould attached to the press and then stamp the same pattern on to each tile as it is produced. The mould is very expensive to design and set-up, which means that once mounted in the press the mould must be used to produce many tiles in order to be cost effective. If done digitally the pattern of relief on every tile could be different, in the same way that the coloured decorative pattern can be changed on every tile using digital inkjet printing today. The structure and coloured decorative pattern could also be synchronised for a more life-like design. Bringing digital technology to this area of ceramic tile production would further reduce the set-up costs and time which could lead to an increase in tiles produced with structure. The future
Integrating the new additions to the Xaar 1002 family available in 2014 and 2015, will be simple for Xaar's existing printer partners; the new printheads can be driven by the same Xaar electronics and software that are available today. These new printheads form part of our continuing investment in R&D aimed at driving Xaar's vision of digitalising the entire tile manufacturing process. To find out more about Xaar's digital vision in ceramics, please read our white paper "Digital Inkjet Ceramics - Where do we go from here?" (link to white paper)
Gillian Ewers, Xaar