HOW DIGITAL INKJET HAS BECOME THE ‘MUST HAVE’ TECHNOLOGY FOR TILE DECORATION

  Mark Alexander, Director of Marketing, Xaar

Mark Alexander, Director of Marketing, explores the compelling reasons that are driving the global adoption of digital ceramic tile decoration

In less than a decade digital inkjet for ceramic tile decoration has matured from simply an ‘interesting’ innovation to a ‘must have’ commercial technology. Today ceramic tile manufacturers can no longer regard offering digitally decorated tiles as an ‘optional extra’ — a digital capability is expected.

The digital inkjet decoration of ceramic tiles has enabled tile manufacturers to reduce costs, streamline production processes, and develop new products and business models. In addition, digital decoration has increased the quality of ceramic tiles, enabled the production of lifelike tiles, encouraged new levels of creative design, and even made ‘on demand’ production of tiles possible.

Breakthrough The first digital tile printer to use inkjet technology came to market in 1999, with limited success.  It wasn’t until 2008 that digital decoration really broke through with the launch of the Xaar 1001 printhead. This printhead features a number of major innovations that have transformed the market’s perception and experience of digital decoration. It is the revolutionary design of the Xaar 1001, with Xaar’s patented TF Technology™ ink recirculation and Hybrid Side Shooter™ (HSS™) architecture which has made it the printhead of choice for ceramic manufacturers today.  Despite other printhead manufacturers’ claims about ink recirculation, only the Xaar 1001’s TF Technology™ combined with HSS™ can deliver the high flow rate past the back of the inkjet nozzle during drop ejection for effective air bubble and particle removal.  This means that no other printhead can deliver the same high levels of reliability and machine uptime whilst also requiring very low maintenance. This printhead was the catalyst that has revolutionised digital decoration of ceramic tiles on an industrial, global scale.

As a result, many of the world’s leading tile producers have chosen Xaar 1001-enabled printers. Today, EFI Cretaprint, Foshan Meijia Ceramic Equipment Co Ltd, Hope Ceramic Machinery Co Ltd, Intesa-Sacmi, KERAjet, New King Time Machinery, Projecta SiTi B&T, TecnoFerrari and TSC all manufacture digital ceramic tile printers that use Xaar 1001 printheads.

The challenges and the solution Tile decoration using traditional analogue roller screen printing is the most problematic stage in the production process. It is a time-consuming process to set up new patterns which results in manufacturers producing long runs of tiles, and holding considerable stock, to ensure consistent batch colour.  The analogue process also restricts tile design options and the limited pattern repeat makes it unsuitable for lifelike production of natural stone effect tiles for example. Another drawback is that, because the pattern rollers touch the tiles during the process, there is an increased risk of breakage.

In contrast, digital decoration is a very flexible and reliable non-contact process which brings multiple production and creative benefits. It enables fast set-up with minimal job changeover, offers effective colour management, minimises waste and is ideal for the production of small batches.  It also enables more lifelike patterns, including printing onto textured tiles, to expand creative design opportunities.

We look at all these benefits in more details here:

Reduced set-up times Using the digital decoration process, tile designs are handled by the printer control software which makes it quick and easy to switch between designs. The operator can even interrupt a production run to test-print a number of different patterns in preparation for the next day’s production; there is no need to wait until the end of the shift.  The minimum print run possible with digital inkjet printing is just one tile, which is ideal for producing test tiles and also perfect for producing small batches of tiles - such as for a one-off custom design.

Lifelike natural stone patterns Using an analogue decoration process, the circumference of the roller determines the length of the image that can be printed, and therefore how frequently the pattern repeats.  This limits design options and prevents manufacturers from producing ceramic tiles that accurately mimic natural stone, marble and wood where the patterns are completely random (so no pattern repeats). With digital inkjet decoration, however, the size of the pattern is limited only by the size of the printer control memory which allows manufacturers to produce large areas of tiles that emulate natural material – with no repeats. Xaar’s next generation of printhead electronics, for example, can store enough data to reproduce a ‘no repeat’ pattern of 40sqm. Inkjet printing can also apply designs of the highest quality and in the finest detail, creating ceramic tiles that are very difficult to distinguish from real marble and stones.

Textured tiles Because digital inkjet is a non-contact process, printers can jet patterns onto on a textured tile surface.  The structure  is added to the ceramic tile ‘biscuit’ during the pressing process, and the printhead is then able to jet ink into the recesses that rotary screen printing cannot reach.  Unlike traditional decoration, digital inkjet printers can also decorate right to the edge of the tiles, eliminating white edges and creating seamless expanses of tile.

No risk of tile breakage Tile decoration takes place while the tile is still fragile, and when screen printing the pressure of the roller can easily fracture the biscuit.  Each time a tile is broken, not only is the biscuit wasted, but also the glaze and inks; combine this with reduced output and there are significant cost penalties. However, because digital inkjet is a non-contact process, there is no risk of tile breakage during the decoration process which reduces waste levels considerably.

Improved colour management Producing consistent, repeatable colour is crucial in ceramic tile decoration, but difficult.  The problem is that the colour of the tile upon leaving the printer is different from the colour after firing. In an analogue process, each roller change has to be followed by at least one test-firing of the printed tile to check colour. This can bring the total changeover time between runs to two hours, and cause more waste and extra costs. With a digital inkjet printer, colour management is software-controlled and, consequently, a more sophisticated and predictable process.  This leads to reductions in the number of glazes and ink sets used. Therefore digital decoration further improves the efficiency and reduces the costs of ceramic tile manufacturing. In addition, as the test tiles can be produced during normal production, no time is lost whilst checking the final fired tile.

Stocks of finished goods and work-in-progress The difficulty of matching colours using the traditional decoration process also encourages long runs and holding of substantial stocks of finished goods.  With traditional printing it is easier to fulfill repeat orders from existing stock than to try to reproduce exactly the same colours and risk problems caused by poor batch control or a slight change in the glaze.  The same is true of work-in-progress tiles, large batches of which are often stacked around a factory awaiting test firings to verify the colour consistency.

The simplicity of colour management using digital inkjet, however, makes it easier to print and replicate patterns and colours ‘on-demand’. Manufacturers no longer need to keep stocks of tiles and they can produce them to order and in any quantity, confident that they will match earlier batches.

Rapid payback The final driver for digital ceramic tile printing is that gaining all these benefits is not expensive — a typical digital decoration printer can be paid for in less than six months.  Production costs are lower (due to reduced tile breakages, for example) and faster. Simpler job set-up enables the short production runs that the market demands, and makes the production line much more flexible.  Reliable software-driven colour management reduces stocks of finished tiles and work-in-progress, freeing up capital.  The memory capacity of the digital system enables patterns of almost infinite size.  Lastly, profit margins are higher, because the final products are of a higher quality and exhibit greater creativity than traditionally-printed tiles.

The reasons to adopt digital decoration are compelling, and so digital inkjet ceramic tile decoration printers will become the dominant decorating technology in a very short time.  This is already the case in Europe, where over 80 per cent of manufacturers have converted and digital is a “must have”.  Now the same digital revolution is taking place on other continents, and in the countries with the largest installed base of tile manufacturing lines, such as China, Brazil, India and Iran.  Combined with a global ceramic tile market that is currently growing at around 10%, there is a huge opportunity for companies who embrace digital decoration.

Visit ceramics.xaar.com to learn more about the significant benefits of digital inkjet ceramic tile decoration with the Xaar 1001.