Acimac Handbooks - Edition 2014/2015

E D I T I O N

ACIMAC

HANDBOOKS

2014 2015

Digital Glazing

Decoration

and of ceramic tiles

E D I T I O N

ACIMAC

HANDBOOKS

2014 2015

Images from the conference Acimac/Tecnargilla "Digital Glazing and Decoration of Ceramic Tiles", Rimini (Italy)

© Copyright ACIMAC, Associazione Costruttori Italiani Macchine Attrezzature per Ceramica Via Fossa Buracchione 84 • 41126 Baggiovara (MO) • Italy • Tel. +39 059 510 336 • www.acimac.it Edito da S.A.L.A. srl • Via Fossa Buracchione 84 • 41126 Baggiovara (MO) • Italy • Tel. +39 059 510 108

In collaboration with:

Introduction

The series of Acimac Handbooks devoted to digital decoration technologies is being expanded this year with the fifth publication which focuses on the latest technological innovations introduced in this specific segment.

Produced in cooperation with the magazine Ceramic World Review, this edition of the handbook will be available at all the leading tradeshows for the sector in 2015 and can also be downloaded free of charge from the page devoted to Acimac technical manuals on the website www.tiledizioni.it.

The aim of the Acimac handbooks is to promote knowledge of technological and process aspects of the ceramic industry through publications that are straightforward and easy to read but at the same time offer exhaustive and detailed coverage of key issues.

The ceramic technology supplier companies have supported us in the-

Fabio Tarozzi

se efforts by making their expertise available and providing the texts.

Given the enormous interest in the theme of “Digital Decoration�, and today in the new field of Digital Glazing, right from the very first edition of the handbook in 2009 it was clear that we would have to provide an update at least every two years.

In the end, the reality of the situation has prompted us to make annual updates.

There are two main reasons for this: firstly, ceramic digital technology is evolving at a rapid pace and has seen the emergence of new market players (machinery manufacturers, ink and service suppliers); secondly, the already large-scale use of ceramic digital printing systems in much of the world is forcing tile producers to broaden their knowledge of available technologies and of the potential for further optimising digital

ceramic production.

The enormous interest in these issues was much in evidence at the 6th Annual Meeting on Digital Decoration organised by Acimac and Tecnargilla in Rimini on 23 September 2014, which was attended by some 700 technicians and professionals from the worldwide ceramic industry.

This new Acimac Handbook contains several of the contributions presented at the conference as well as fresh material provided directly by sector companies operating in the fields of colour management, digital glaze and ink supply and inkjet printing machine construction.

We feel certain that it will make an important contribution to the knowledge of industry professionals in Italy and abroad.

We are also convinced that research in this field will continue steadily and will bring further advances in the near future.

Fabio Tarozzi Acimac Chairman

Contents Colorobbia Digital Space: digital evolution continues ............................................. pag. 2 Esmalglass-Itaca, new digital solutions for the ceramic market ............................. pag. 6 INCO Quick Stain Pigments for ceramic inks......................................................... pag. 8 Diversa, a new concept in ceramic production.....................................................................pag. 12 The innovation of Durst digital decoration technology........................................................pag. 16 Innovative solutions for rapid and cost-effective prototyping The infinite potential of the digital revolution

..........................................pag. 22

.......................................................................pag. 28

Advanced colour management solutions for ceramic digital decoration Breaking the paradigm of submicron ceramic pigment suspensions

.......................pag. 32

............................pag. 36

Fabio Tarozzi

Colorobbia Digital Space: digital evolution continues

by Fabio Avoni

At a time of continuous technological advances in the ceramic industry, Colorobbia is unveiling the latest innovations in its Colorobbia Digital

Space range.

Rather than just a range of materials for digital technology, Colorobbia Di-

gital Space is a series of integrated solutions incorporating concepts such as design, inks, glazes and technology.

THE COLOROBBIA DIGITAL SPACE RANGE CURRENTLY INCLUDES:

• EHP SERIES (Extended Hydrophilic Properties).

This well-established series has been on the market for several years and has enabled Colorobbia to secure a leading role as a supplier of materials for digital decoration.

Its main characteristics are the extremely high stability of the ink system, the wide range of colours and the extremely high compatibility between the ink and water, especially the water contained in the materials typically used on the line (engobe, glaze, etc.).

This characteristic of the EHP series avoids the many surface defects and application problems that may arise as a result of total incompatibility between water and a number of organic solvents.

The EHP series includes the C-Inks family (pigmented inks), the C-Glaze family (special effect inks such as matt, white and sink-in inks) and the C-Shine family (unconventional effects such as metallised inks).

• ETR SERIES (Extended Temperature Range).

This new range was recently launched onto the market as an interesting alternative to the previous series.

With this new range, Colorobbia offers its customers a series of inks that maintain high performance and productivity even in critical process conditions such as high tile temperatures and the emission of large quantities of water

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vapour.

This new range follows in the footsteps of the previous series (C-Inks, C-Glaze and C-Shine) while bringing this important additional benefit, which is particularly useful in certain production conditions. Other factors such as gamut and stability of the material remain unchanged.

With these two series Colorobbia offers its customers a complete range of inkjet inks that above all guarantee the maximum performance in all possible production conditions.

But the Colorobbia Digital Space range is far more than this.

Unlike just 5 or 6 years ago, the benefits of digital decoration are now widely recognised. Exploiting the advantages of this technology, research efforts currently focus on the application of greater quantities of material than is possible with traditional inkjet technology, the use of even more functional materials, greater customisation of the finished product and optimisation and increased efficiency of the process. This may lead to complete digitalisation of the glazing line by combining both digital decoration and digital glazing.

What once might have been considered a distant dream is now ever closer to becoming reality.

Colorobbia believes that this goal can be achieved through two complementary solutions: low discharge glazing and high discharge glazing.

• High discharge: pin this solution material can be deposited in quantities ranging from 300-400 g/m2 to 1 kg/m2 or more but with a lower resolution than with conventional inkjet printing.

The technology is suitable for both floor and wall tiles and is highly versatile in terms of its position within the ceramic production layout. In this case, the machine used for applying material can be positioned either before the colour inkjet printer (for example, to replicate a texture without the need for special moulds or to apply a full field of engobe/glaze) or after it (to deposit a sufficient quantity of material for subsequent honing or polishing operations).

• Low discharge: material can be deposited in quantities ranging from a minimum of 30-40 g/m2 up to 200/300 g/m2 with high print resolution.

Here too the application is suitable for both floor and wall tiles.

The machine can be positioned either before or after the inkjet printer and can exploit the enormous potential for design synchronisation offered by digital technology.

This solution also offers unlimited potential for customisation as a result of continuous dialogue between all the machines.

Based on this philosophy, Colorobbia has developed two new series of materials to meet all the needs of its ceramic manufacturer customers: the HQ series and the SPS series.

The HQ Series is intended mainly for high discharge applications and includes water-based materials with a particle size that is smaller than that of conventional glazes but higher than that of digital inks.

This series has a D100 below 20 microns. Colorobbia’s current range consists of an engobe, a glaze-engobe, a matt glaze, a transparent glaze, a super white glaze and a waxy glaze, as well as more sophisticated effects such as lustre and metallised effects.

These materials were originally created for use on floor tiles but can also be developed in a version for wall tiles.

Photos 1 and 2 show two products obtained with these materials.

Colorobbia would also like to clarify its position with regard to the definition of water-based materials.

This term is widely used in our sector, but what does it really mean?

A water-based material is a system

containing a significant percentage of water, which in our sector can be defined as around 30-40%.

Materials with a smaller percentage of water or which do not contain water at all but are compatible with water cannot be described as water based.

Conversely, in the accepted meaning of the term a water-based material does not necessarily contain 100% water as the solvent.

For low-weight glazing, Colorobbia is proposing its new SPS series.

This series meets printhead manufacturers’ requirements for application of low-weight materials.

It consists of solvent-based materials with a new and innovative particle size distribution.

This particle size distribution makes it possible to obtain more intense shades of notoriously pale colours such as yellow and pink and above all allows

for the use of materials that can provide depth and thickness rather than just colour, achieving surface effects and textures that were previously unimaginable with digital technology.

Colorobbia can already supply colours such as yellow and pink as well as effects such as matt and transparent glaze. If these effects are applied using a double bar, they can create a ceramic surface that is equal if not superior in functional terms to conventional glazes.

Photos 3 and 4 show two products created using some of these materials.

FIG. 3 -SPS series matt glaze on glossy base

FIG. 1 - HQ series glaze-engobe for texture effect

FIG. 4 - Interlocking matt glaze and gloss finish, both SPS series

FIG. 2 - HQ series matt glaze

Acimac handbooks - 2014 Edition . 3

All digital products supplied by Colorobbia are fully tested and approved by most major machine and printhead manufacturers.

As a result of this extensive ongoing collaboration with the leading OEMs, Colorobbia has already performed industrial testing on SPS series products at the facility of a leading Italian ceramic company, which has produced various models of tiles on an industrial scale exploiting the unlimited decorative opportunities offered by digital application technology.

In view of the advantages of digital technology, Colorobbia believes it will be possible to obtain a finished tile that is completely glazed and decorated using digital applications.

For this purpose, Colorobbia offers highly functional materials which when

combined interact in a sequence of layers to produce an innovative and entirely digital tile.

These materials are highly functional due to interaction between the sequence of layers deposited on the ceramic surface.

This interaction makes it possible to use a smaller application weight than would be necessary with a conventional process, allowing for effects and textures that would not otherwise be achievable.

Another functional material capable of producing effects that would not be possible with traditional techniques is the patented C-Shine series, unveiled

by Colorobbia at the ACIMAC conference on digital decoration technologies held in November 2012. By applying an interphase using one of the two inks in

the range (“gold” effect or “silver” effect), it is possible to achieve innovative optical interference effects such as metallised or terracotta.

Highly versatile effects and colours can be obtained by varying the material application weight.

This versatility also brings significant benefits in terms of costs as Colorobbia is able to innovate its products simply by using a material like C-Shine ink.

While waiting to see a fully digital production line installed in a factory, Colorobbia has developed a wide range of materials to meet the technological needs of end customers and is continuing its R&D efforts at its various laboratories.

These materials are shown in the following diagram.

THE RANGE OF COLOROBBIA PRODUCTS IS SHOWN IN THE TABLE

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CONCLUSIONS

Colorobbia Digital Space offers much more than a simple colour chart or a single test run of a digital effect/glaze.

Colorobbia Digital Space brings customers a series of essential characteristics based on its 90 years of experience: reliability of mate-

rials, safety before and after the process to protect personnel and the environment, a worldwide technical service with unrivalled speed and quality and branches located in all existing and newly emerging ceramic production areas, proprietary know-how

of all production processes, and teams of technicians specialising in basic product research and finished projects.

These key values have one thing in common: the commitment of employees to the company and above all to customers.

NOTES

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Esmalglass-Itaca digital solutions for the ceramic market

by Armando Meletti, Alessandro Ferrari ADVANCED DIGITAL TECHNOLOGY FOR MATERIAL APPLICATION

The digital revolution in the ceramic industry that began with pigmented inks now offers enormous production and economic benefits for ceramic floor and wall tile manufacturers.

But why consider only the advantages of digital decoration when ceramic is far more than this? Ceramic is a combination of textures, contrasts, brightness and different surfaces that are achieved through the application of material. And if this material can be applied using a digital system capable of performing decoration and glazing simultaneously and in a synchronized manner, this will bring further benefits alongside the many advantages already offered by digital technology.

This is why Esmalglass-Itaca set its sights on developing materials for digital application. After many years of research and experimentation, it has finally developed two new groups of products that can be applied to ceramic surfaces using digital systems: Digital Effects and Digital Materials.

These two families complement the already wide “Digitalinks” range of digital inks that our customers have been using to decorate their products for years.

These two families of products are designed to give customers the op-

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portunity to create an entirely digital process.

The “Digital Effects” series consists of submicron products suitable for use with today’s printheads, nanometre-scale particles whose particle size distribution ensures excellent physical stability along with optimum performance. This category comprises materials that complement the decoration and create special effects. These include: a white effect used for decoration or as a base for digital inks; a transparent shiny effect designed to create contrasting matte-gloss areas; and a transparent matte glaze that creates small variations of level in the base glaze, resulting in micro-reliefs.

The “Digital Material” series consists of micron products designed for use with the new high-discharge printheads. They allow for material application weights well above 100 g/ m2 and as high as 1 kg/m2 or more.

They are water-based materials with a particle size greater than 3 microns. This larger particle size with respect to submicron materials has a direct influence on the ceramic effect, resulting in digitally deposited application weights that are comparable with the quantities currently

deposited by bells, flat screen printing machines, rollers and fumés.

These products also have a significantly lower price than submicron materials, which is essential for industrial operation with high application weights. These two factors have made a key contribution to the feasibility of a fully digital ceramic production process.

The Digital Material family includes: matte white, transparent white, transparent matte satin, crystal and metallic for monoporosa tiles and porcelain, and a lustre. These products can be applied full field in thick layers, before or after decoration, or as clearly defined designs synchronized with the rest of the process to create thickness effects, as with screen printing or rollers. They can even be used to create reliefs, an operation that is currently only possible with a press mould. They allow for the same kinds of applications as existing methods but with all the productivity advantages of digital technology.

Esmalglass-Itaca has been studying and developing these kinds of materials for a number of years; they first came to public notice when the company won the Alfa de Oro award

at Cevisama 2011 and consequently patented its high discharge digital micron glazes.

Both type of materials, micron and sub-micron, are designed for application on all kinds of tiles: monoporosa, porcelain, stoneware, double-firing, etc.

All compositions have been optimized to meet the aesthetic and technical characteristics required by today’s ceramic industry while maintaining the high colour performance of Esmalglass-Itaca pigmented inkjet inks.

Using a fully digital process with the materials that Esmalglass-Itaca is offering the market brings countless advantages, including improvements to products and benefits in terms of the production process and management. Aesthetic advantages include new finishes and structures and a simpler development process.

The benefits regarding production and management include a shorter production line, faster new product development times, reduction or elimination of the expendable supplies of traditional decorations, greater flexibility and speed in model changeover and a smaller number of co-

lour tones, resulting in simpler warehousing operations.

Last but not least, the Digital Solutions family from Esmalglass-Itaca consist of more than just digital colour – they decorate tiles by actually applying a layer of material. This gives tile manufactures and designers the opportunity to create products that are clearly differentiated and are manufactured using a fully digital process.

In its renovated showroom in Villarreal, Esmalglass-Itaca Group is also presenting an exclusive display area for large-format tiles, from 240x120 cm up to 320x160 cm or larger, with a variety of sizes obtained by cutting the large panels. Decoration can be performed before or after compaction, for which purpose Esmalglass-Itaca offers a highly comprehensive range of products: from the colours to be applied to the earths, atomized glaze and flakes to produce a richly coloured body; to the above-mentioned inks, digital effects and materials, up to glazes, colours, grits and granules to obtain extremely natural looking or highly polished finishes.

NOTES

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INCO Quick Stain Pigments for ceramic inks

by Daniele Verucchi, Angelo Lami, Maurizio Cavedoni

INCO Industria Colori has developed a specific range of ceramic pigments for ink production with exceptional technical characteristics.

These products are aimed at ceramic glaze and colour producers and ceramic tile manufacturers interested in starting up their own independent production of pigmented inks.

The technical characteristics are a result of complete pigment reformulation, meticulous selection of the raw materials and a thorough review of the production process.

This completely new range of dedicated pigments is already used in the production of INCO INX and can produce excellent quality inks quickly and with considerable savings.

For this reason the range has been named QUICK STAIN. Pigmented ceramic inks are dispersions of a solid inorganic pigment phase in a liquid phase (solvents with varying degrees of polarity, dispersants, rheology modifiers).

The production of these inks is based on a process of reducing the pig-

ment particle size (a “top down” process) through high-energy grinding in special mills with grinding chambers filled with microspheres of diameter of 0.3-0.4 mm (Photo 1).

During the process, a homogeneous mixture of solvent and pigment is circulated for several hours through the grinding chamber, while a special rotor imparts a high peripheral velocity, and hence high energy, to the spheres. This continues until the inorganic pigment has an average particle size of 250-350 nm and a d99 of 0.8-1.3µm (Photo 1b).

FIG. 1 - Ink Mill

FIG. 1B - Ink Mill

FIG. 1C - Ink Mill

CHARACTERISTICS OF CERAMIC PIGMENTS

Unlike the organic pigments used for production of inks for printing on paper and fabrics, inorganic pigments have a high Mohs hardness (>67) and a high specific gravity (>4 g/ cm3) (Photo 2).

This high degree of hardness means that a lot of energy (2-4 kWh/kg) and long milling times are needed to achieve the requisite ink particle sizes. This results in low levels of plant productivity, high energy costs of production and considerable wear of the grinding spheres and mill chamber components.

Due to the high specific weight of the pigment and the larger particle size with respect to other types of inks, ceramic pigmented inks are more

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FIG. 2 - Properties of inorganic pigments

susceptible to sedimentation.

The properties of the inorganic pigment play a key role in the design of a high-quality ink.

In particular, the particle size distri-

bution, morphology and homogeneity of the particles have a significant influence on the end characteristics of the ink in terms of colour gamut, filterability and sedimentation.

PRODUCTION OF CERAMIC PIGMENTS FOR INKS

The inorganic pigments used in ceramics are synthetic products obtain from a high-temperature (1000-1400°C) solid-state reaction of mixtures of transition metal precursors (Fe, Cr, Ni, Co, Mn, Zr, etc.). This high-temperature process produces coloured crystalline structures (spinels, zircons, sphene, etc.) that can be used for colouring ceramic glazes or as a solid component for the production of inks.

The pigments used for ink production must have very specific characteristics: 1) Low percentage of salts: a washing process is therefore required.

2) High colour intensity: a limited quantity of pigment can be introduced as solid phase.

3) Colour gamut: each pigment must produce the maximum specific colour range.

B Y P narrow Rb G 4) A particle size distribution: the narrower the particle size distribution at the entrance to the grinding mill, the narrower the distribution curve in the final ink.

This is preferable as it allows for the production of inks with superior colorimetric properties and stability.

Pigments for ink production currently undergo a dry pre-milling process using Jet Mills.

These consist of compressed air counter-jet mills (up to 6 atmospheres) in which the grinding action is achieved by impact between the particles.

The narrow and fine distribution of the particles is guaranteed by a

classifier that rotates at different speeds according to the desired particle size (Photo 3).

This grinding technology has certain particle size limitations in terms of the coarse fraction, especially as regards the particle fineness specifications required for ink production.

Laser diffractometer measurements of the particle size distribution of products obtained from Jet Mills reveal values of d50=2-3 µm and d99=5-7 µm, which are certainly very good values.

However, if we analyse the particle size distribution in greater detail, we find that d100 can reach values as high as 10-14 µm, revealing the presence of a grinding tail consisting of coarser particles which are sometimes not detected by the instrument.

The situation proves to be even worse when analysing the pigment under the scanning electron microscope (SEM), which is capable of measuring the real size of the particles as well as analysing their morphology.

Photo 4 shows the particle size distribution of a yellow pigment milled in a Jet Mill as measured using a laser diffractometer.

Although 100% of the particles would appear to be smaller than 10 micron, this is simply not the case.

Analysing the photo taken under the scanning electron microscope, we find particles larger than 10 microns and with dimensions as large as 25-30 micron.

Furthermore, the pigment displays a significant degree of nonuniformity in terms of particle size and shape.

Although these particles are not

FIG. 3 - Jet Mill

FIG. 4 - Yellow pigment milled with Jet Mill technology

Acimac handbooks - 2014 edition . 9

FIG. 5A - Comparing particle size distributions. Standard yellow Jet Mill pigment (left) compared with yellow Quick Stain (right)

FIG. 5B - Yellow Quick Stain pigment

large in number, their presence can nonetheless create problems during the submicronic milling process.

According to milling theories, these larger size crystals would require grinding spheres of diameter 1.0-1.5 mm, which are too large to produce the required ink particle sizes of 0.20.3Âľm.

These particle size values can be obtained using spheres of diameter 0.3-0.5 mm.

With these sphere dimensions it takes a very long time to reduce the size of the large particles and these long milling times have the negative consequence of creating a fine particle size tail in the final ink.

These particles result in a loss of colour in the ink and rheological problems.

Exploiting its more than 25 years of experience in the field of inorganic pigments, INCO has conducted a study aimed at developing a new series of pigments with significantly improved particle size and morphological properties compared to those produced in a conventional Jet Mill.

The Quick Stain pigments have a particle size distribution with an average value of 0.7-0.9 Âľm and a real d100 of below 3 micron measured from images made with a scanning electron microscope, as well as particles with more uniform shape and size.

Photos 5a and 5c compare pigments obtained with Jet Mill grinding technology (left) with Quick pigments (right).

As can clearly be seen in the photos, the Quick series pigment particles are considerably finer and more uniform (Photos 5a, 5b, 5c).

These properties of Quick pigments result in an ink with a narrower particle size distribution than a pigment deriving from a Jet Mill process, as can be seen in Chart 6.

The image for Quick Yellow ICQ 10/ Q110 appears to show a fused, spongy, almost sintered mass. In reality, as can be seen in the following image taken at a larger magnification, it is an aggregation of primary particles created by electrostatic attraction between very fine particles, with average particle size values of around 600-700 nm.

THE ADVANTAGES OF QUICK FIG. 5C - Comparing particle size distributions. Standard brown Jet Mill pigment (left) compared with brown Quick Stain (right)

Due to their finer size and narrower particle size distribution, Quick technology pigments are most suited for the production of high-quality ceramic inks (Chart 6).

They give the following advantages: 1) More intense colour.

Narrowing the Gaussian grinding curve reduces the quantities of the finest and coarsest particles, automatically increasing colour intensity.

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2) Lower sedimentation and creaming.

A more uniform particle size results in a reduction in sedimentation and creaming.

The product remains rheologically stable for a longer period of time.

3) Greater colour stability.

More uniform particles result in production batches with more consistent colour while maintaining the same fire resist-

ance.

4) Improved filterability.

Quick pigments have a more regular shape, which is maintained even after Ink Mill grinding. The particles therefore always have the same size at the filter.

Other kinds of pigments are liable to create inks with lenticular shaped particles and thereby give rise to problems of filterability on decorating machines.

FIG. 6

This brings savings of at least 30% for ink producers.

5) Energy saving during grinding.

Due to the very fine particle size, the narrow Gaussian curve and the controlled shape of the particles, it is possible to reduce the grinding times by 30-40%.

6) Reduction in wear of grinding media.

The expensive grinding media (spheres) are used for less time.

7) Reduction in mill wear.

The expensive internal lining of the mill is used for a shorter time.

8) Smaller plant investment.

All the above-mentioned savings lead to a reduction in investments in milling machinery as a result of the considerable increase in production capacity.

THE QUICK RANGE

The Quick Stain range consists of 14 high-saturation pigments with a particle size below 3 microns. They cover a wide gamut and enable ink manufacturers to offer a wide range of colours.

In keeping with the INCO tradition (Sarti del colore dal 1988 - Colour tailors since 1988), specific colours can naturally be developed to order using Quick technology.

FIG. 7 - The Quick range

Inject high quality into your ink system!

Acimac handbooks - 2014 edition . 11

Diversa, a new concept in ceramic production

by Rita Cagnoli

In theory, inkjet printing is a simple process: a printhead deposits drops of product onto a substrate.

But in practice, this technology is complex and requires multidisciplinary expertise to implement.

To be performed correctly, the entire decoration process must be meticulously designed, implemented and managed, taking all factors into consideration.

But if it is so complex, why is the ceramic industry choosing to adopt the inkjet process for decoration?

The first reason is that inkjet is much more than a simple printing technique. It can be used for applying coatings, for depositing specific quantities of material with a high degree of precision and for creating microstructures. Inkjet technology would appear to have unlimited uses and offers numerous advantages: a major reduction in production costs; higher quality; a reduction in warehouse stock; the ability to work on large surface areas; complete customisation of the product; rapid prototyping and just-in-time production.

The introduction of inkjet technology to the ceramic tile industry may bring just minor improvements or it may prove revolutionary, but in any case the commercial benefits are generally very significant.

Inkjet technology is now a reality in many different sectors, ceramics being one of the industries that has benefited the most.

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Digital technology has revolutionised tile production and digital printers are now widely used both in Italy and abroad.

In ceramic factories in the past, specialist female workers would pour the glaze over the flat ceramic surface from wooden bowls to avoid contaminating the glaze.

This was the first surface glazing process. Step by step this led to curtain coaters and bell applicators.

Now that many of the processes have been digitalised, it is only natural that this stage of tile decoration cannot continue to be performed analogically.

For this purpose, System’s latest invention - called “Diversa” - revolutionises the decoration department, converting what has always been considered a harsh and difficult environment into an almost aseptic workplace.

The Diversa glazing and decoration process uses water-based materials and inks with a low environmental impact.

All the decoration stations (up to 36 applications) are concentrated in a space of just 25 linear metres compared to the 130 metres occupied on average by current glazing lines.

Diversa will therefore bring considerable savings in terms of space. The use of the future tense here is obligatory because System’s invention is ahead of its time, and like all great

ideas will require a period of time to be accepted by industrialists before it is installed in factories. It will take foresight to choose to adopt this new process. “We are a research company,” notes Franco Stefani.

“You can’t keep research on the back burner. You have to document it and present it to the market to make it the benchmark and to initiate a process of debate and discussion with customers.”

Returning to the technological system presented by System, Diversa incorporates all the stations that make up a ceramic decoration process. The first station is glazing, followed by the liquid decoration stages (pigmented inks and new-generation materials), then a second glazing station for protection and finishing, and finally dry decoration.

Encouraged by the success of the Creadigit printer, System began developing a system that would be capable of performing digital glazing using piezoelectric DOD technology, the same technology that is successfully used on what are now standard decorating machines.

A simply engineered head with recirculation was chosen to enable water-based products with a particle size of 6 µm to be used. The resultant machine, called Layerdigit, is able to load a maximum of 4 different products and deposit up to 400 g/ m2 of material per application.

LAYERDIGIT

Layerdigit is the first station in the ceramic production line of the future, called Diversa.

By using digital technology, this line will be capable of glazing, decorating, creating effects and reliefs and depositing protective layers on the tile – all in a space of just 25 metres.

The Layerdigit philosophy involves depositing a sufficient quantity of material on the tile to ensure total coverage with maximum uniformity and absorption of the deposited material. The 360 dpi resolution is important in order to achieve perfectly uniform product application and to completely close the surface porosity.

Given the large quantities of product deposited on the tile, it is essential to develop materials that have a high

percentage of water along with the solid component and organic phase to avoid burning large quantities of solvents.

System is currently working closely with Italian ceramic glaze and colour producers to develop products and raw materials that can be used with this technology to achieve very high yields.

It will be possible to install high-resolution (400 dpi) and low-resolution (200 dpi) decoration stations on the line to attain the highest degree of production flexibility.

The entire line will be equipped with a single high-precision conveyor belt to ensure perfect synchronisation between all the printing stations. With applications that include glaze-en-

gobes, glazes, coloured, gloss and matt effects, colour designs (up to 16 colours), metallic effects, protective layers and powder applications with Windpowder etc., the new line will combine cutting-edge technology with outstanding scope for creativity. The large printing width (minimum 1200 mm) together with a belt speed of 10 m/min. will ensure the same levels of productivity as narrow high-speed lines. This means that the line will be able to work simultaneously on different sizes with different applications loaded on the machine bars. The System machine used for dry decoration is Windpowder, which combines the effectiveness and innovation of digital technology with the potential for decorative and material effects offered by powders.

WATER-BASED INKS

Standard water-compatible inks are being developed to harmonise the line’s applications and guarantee the maximum compatibility between one decoration station and another.

Solvent-based inks are the most widely used products on inkjet ma-

chines due to their good printing quality, the stability of their formulation, the range of compatible processes and their good functionality inside printers.

Water-based or water-compatible inks have the advantage of being rel-

atively inexpensive and environmentally friendly, but industrial take-up has been slow and the ceramic industry has only just begun to adopt them.

On its printers System has chosen to use printheads that can operate

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with both solvent-based (non-polar) and water-based (polar) systems.

The water-based inks currently being studied by System are synonymous with quality, eco-sustainability, technological innovation and cost-effectiveness.

One of the most important factors behind the decision to change course and consider water-based inkjet systems for the ceramic industry is the environment.

Water-based inks guarantee a significant reduction in polluting emissions along the entire production chain.

They contain about 50% less organic chemical components and produce far fewer combustion products with

a low odour threshold (VOCs, Volatile Organic Compounds); energy consumption for ink production is reduced (water makes the grinding process more effective); solvents do not need to be used for washing the production plants as everything can be washed with water; the energy used for disposing of the washing solvents and containers used for storage is reduced (all materials can be released to wastewater without the need for special treatments).

The technological innovations include the total absence of water-repellence with respect to glaze applications before and after decoration, compatibility with water vapour present in the tiles passing

underneath the digital printer, faster drying on the ceramic tiles compared to solvent-based inks, reduction in surface defects caused by combustion of organic chemical components, and ease of washing of the circuits and external parts of the printer.

Diversa is built entirely by System.

This includes hardware (mechanical design, manufacture of components, design of hydraulic system and study of materials), software, electronics, image processing and formulation of the inks and products used. All machines in the Diversa system are fully integrated and synchronised.

SYSTEM ELECTRONICS: THE ADVANTAGE OF SIMPLICITY

System itself designs and builds not only the mechanical parts of the automations but also all the electronics.

System Electronics is the company business unit devoted to the development of software and hardware solutions.

“Exploiting the experience we had gained with the Creadigit digital printer, we developed a new electronic system that could deliver the

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high performance required by Diversa. First and foremost this means more processing power,” explains Alessandro Benassi, division manager at System Electronics. “From the dual core processor of Creadigit, we proceeded to the quad core + GPU of Diversa.

The capacity for communication with the printheads has increased fourfold, making it possible to control multiple heads and therefore deco-

rate large format tiles without any loss in performance.”

Printhead synchronisation on Diversa is performed virtually by means of Ethercat, allowing different types of bars to be managed in complete freedom regardless of their position. The new decoration process presented by System takes place in a space less than 30 metres in length incorporating all the various tasks.

The specially developed electronic platform can be dynamically reconfigured to meet the multiple task requirements of Diversa, including the application of glaze, colours, powders and glassy coatings – operations that use different kinds of heads.

The entire electronic system has been integrated into the colour bar, considerably simplifying the machine and reducing overall dimensions.

The printheads are managed by means of a high-speed bus with the

possibility of operating at up to 4 Gbit.

In this configuration, a single cable carries all the printing information regarding both images (what to print) and synchronisation (when to print). This does not impose limitations on the width of the printing area, resolution or line speed.

The upgraded Coredigit, the core of the colour bar’s processing unit, is able to handle large image areas and to load new graphic designs at the same time without interfering with

normal production.

The new electronic equipment developed for Diversa also includes the Copilot 21.5’, a latest generation touch screen developed as an operator interface by System Electronics.

Copilot is equipped with a low-power processor with a wide operating temperature range and full HD high-definition retro-projected capacitive touchscreen.

The bluetooth interface enables it to recognise users authorised to perform advanced operations.

NOTES

Acimac handbooks - 2014 edition . 15

The innovation of Durst digital decoration technology

by Norbert von Aufschnaiter

from left: FIG. 1 - Image courtesy of Ceramica Sant’Agostino, Italy FIG. 2 - New Durst Gamma XD Series

FIG. 3 - Durst milestones in the ceramic digital sector

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Durst, the industrial inkjet specialist, is the most successful printing machine manufacturer for digital decoration of ceramic tiles with over 500 installations worldwide. Customers choose Durst Gamma inkjet printers for their high print quality, productivity and reliability.

Durst Single Pass Technology for ceramic tile decoration began its development in 2003. In 2004 Durst presented Gamma, the world’s first

high-performance digital printer for industrial ceramic tile decoration designed for pigmented ceramic inks.

This machine marked the first step in the digital revolution in ceramic tile decoration and production.

Since then, Durst has continued to make major innovations in close cooperation with its customers, contributing to the success of many leading ceramic tile manufacturers around the world.

As a result, Durst Gamma inkjet printers have quickly become the industry standard for print quality with high uniformity and strong colours, flexibility, productivity and reliability.

At Tecnargilla 2014, Durst once again demonstrated its ability to innovate with the launch of the new Gamma XD Series and the introduction of the new Digital Glaze Line concept.

NEW DURST GAMMA XD SERIES

The Gamma XD Series is Durst’s new-generation 8-colour ceramic inkjet printer platform designed for long-term high-precision printing with ultimate colour stability and print uniformity.

Alongside technological innovations, the machines have sophisticated new features including modularity and an integrated self-maintenance capability.

The Gamma XD platform is the basis for different printer versions to meet the requirements for current and future tile sizes.

The Gamma XD Series is equipped with the latest Durst High Definition Printhead Technology with dual ink circulation and can be configured

with up to 8 printing bars (photo 4).

The new Gamma XD Series decorates tiles with a native resolution of 300 dpi combined with the innovative Adaptive Dot Placement Technology.

It prints with 4 greyscale levels and drop sizes up to 90 pl.

For special effects such as glossy, matt, lustre and metallic inks, printheads with drop sizes of up to 320pl are optionally available.

An intelligent Electronic Printhead Alignment System combined with the Adaptive Dot Placement Technology guarantees banding-free printing for high image quality and colour homogeneity across the entire printing width.

A new printhead cleaning and ink filtration system with almost no loss of ink guarantees consistent print results and a long life cycle for the printheads with long maintenance intervals and avoids purging the ink on the transport belt.

The entire belt transport assembly can easily be cleaned without the need for consumables (brushes or liquids). The new ink filtration system avoids nozzle blockages and assures high printer reliability and uptimes. The integrated main ink tanks are protected against dust and water by swing doors.

The Durst proprietary Ink Cubitainer System with rapid connector enables spill-free and safe ink refills.

FIG. 4 e 5 - Durst Gamma XD: ergonomic control panel with adjustable height

SAFETY

The Durst Gamma XD Series include several features for all-round op-

erator safety, including fully closed printer design, efficient ink evapo-

ration and aerosol extraction, ink certification geared to maximum op-

Acimac handbooks - 2014 edition . 17

erator safety and printer reliability/ performance (photo 6). An automat-

FIG. 6 - Durst-GammaXD, ease of access and protection

ic tile thickness/profile scanning system and print engine control as-

sures non-stop printing to avoid unnecessary line stoppages (photo 7).

FIG. 7 - Durst-GammaXD, safety in production

EASY AND QUICK PRINTHEAD REPLACEMENT

The new printheads are also designed in such a way that they can easily be replaced and re-adjusted by the operator within a very short time so as to minimize downtimes.

The new Gamma XD printers are equipped with Remote Diagnostics Technology and enable customers to

FIG. 8 - Easy service access from both sides FIG. 9 - Easy printhead replacement (patented)

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perform all regular maintenance and service work themselves, including printhead replacement, without the need for Durst assistance.

The machines provide easy service access from both sides and guided procedures for fast and easy replacements and alignments (photos

8 and 9).

The new printer design of the XD Series incorporates the optimization of the machine’s ergonomics to further improve the work process. The control panel can be adjusted in height, rotated and easily adjusted on site for left or right handed operation.

THE BEST RATED PRINTER SOFTWARE FOR HIGH PRODUCTION EFFICIENCY

FIG. 10 - Printer management software

The Gamma XD Series is equipped with the best-rated multilingual printer software (64-bit Linux) for easy and fast operations.

The operator can choose between many languages to customize the user interface.

The software provides high flexibility and various new features to optimize the digital workflow, e.g. the unique Durst Autostructure function for automatic structure creation when using special effect inks such as lustre, sink-in ink, etc. (photo 10).

DURST DIGITAL GLAZE LINE

With the new Digital Glaze Line concept, Durst is introducing an innovation that will revolutionise ceramic tile production through synchronisation of the digital glazing, printing

and finishing processes (photo 11).

This will allow for greater creativity, efficiency and precision, resulting in true on-demand production without the need for further production

stages, from the computer through to the finished product. The Digital Glaze Technology will allow ceramic tile companies to apply glazes with full or partial coverage, to create

FIG. 11 - Durst Digital Glaze Line

Acimac handbooks - 2014 edition . 19

structures that are aligned perfectly with the design and to offer new design possibilities that could not be achieved with traditional glazing technologies.

For example, wood decorations can be produced with the same wood grain or in random mode.

Alongside its precision, the Durst Digital Glazing Technology also offers the advantage of being able to produce an unlimited number of different structures.

Today, a maximum of 4 different structures can be produced with a

printer depending on the design and tile size.

Digital Glaze technology can be installed before the current digital decoration printer to glaze tiles with flat or textured surfaces, or after the printer to apply special effects or crystalline, etc. (photos 12 and 13).

The main advantage of this innovative technology compared to the other solutions on the market is that it can jet large quantities of glazes with particle sizes close to those of traditional glazes, thereby achiev-

ing cost-effective applications without losing the real ceramic effects.

This makes it possible to streamline the production process, increase efficiency, reduce waste and minimise finishing costs.

The new Gamma XD series is already equipped with a software interface to synchronise with Digital Glaze technology.

Durst is also planning to develop connections for third-party printers so as to offer the system as a standalone solution.

FIG. 12 - Digital Glaze technology

FIG. 13 - Digital Glaze technology

PARTNERSHIPS

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Durst offers leading industrial printer technology with the highest installed base (over 5,000 indus-

trial printers installed worldwide).

Durst’s experienced staff provides high level support, knowhow and ex-

perience in digital imaging to assure successful production start-up and operation.

Durst also provides comprehensive factory and on-site training for ap-

plication, digital workflow and service/maintenance operations.

NOTE

Acimac handbooks - 2014 edition . 21

Innovative solutions for rapid and cost-effective prototyping

by Alessandro Beltrami

Glaze and colour producers, third fire ceramic tile producers and laboratories are experiencing a growing need to perform tile prototyping as part of their R&D activities and for small special production runs, such as those with precious metals.

For these kinds of activities, normal single-pass digital decoration printers are often not sufficiently versatile, either due to their limited abil-

ity to support multiple ink changes or simply because of quality issues deriving from the fixed transversal printhead resolution.

For real prototyping or small just-intime production runs, certain activities need to be performed quickly, reliably and cost-effectively: • Scanning of stone, wood and other natural materials • Automatic colour management

• Plotter with quick ink change.

Intesa’s solution consists of three devices that can be combined perfectly to meet the needs of ceramic glaze and colour laboratories, third fire tile producers and companies wishing to prototype products without occupying lines and single-pass digital machines.

IMAGO – XL IMAGE SCANNER

Imago is a photographic scanner that acquires images of stone, wood and other flat materials without the need to break them into small pieces. Imago uses 2,400 dpi autofocus optics and is designed to reproduce colours and details with a high degree of accuracy so that they can be replicated with Intesa digital printers with the aid of the Crono colour management system.

Its solid structure enables it to easily handle ceramic panels up to 1x1.5 metres in size and weighing up to 150 kg.

The project was developed by Intesa with the goal of obtaining a robust and simple machine that would be easy to install and above all much less expensive than other acquisi-

FIG. 1 - Imago - XL image scanner

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. Acimac handbooks - 2014 Edition

tion systems.

It was created by adapting one of the best commercial optical systems on the market, produced by Seiko Epson, and fully exploits the system’s ability to acquire details and colours on smooth and slightly textured materials.

With an optical density of 3.8 DMax it can detect contrast on the most strongly variegated stone, while the native colour depth is 48bit.

This means that it can acquire almost 300 trillion (3x1014) colour combinations compared to the 16 million colours of normal 8 bit per channel devices!

Ceramic producers often require a spectral scanner, so let’s look at

why Imago may offer a valid alternative. A spectral scanner normally consists of a high-resolution camera but with a lower DPI than the native 2,400 of Imago.

Filters are used to split up light solely across the visible spectrum (spectral scanner) or including part of the infrared and ultraviolet component (hyperspectral scanner).

This means that the same device can acquire graphics and testcharts, whereas with an RGB scanner like Imago a spectrophotometer is required.

The list of the pros and cons of Imago compared to a spectral scanner shows that it is difficult to make a direct comparison between the two devices:

FIG. 2 - Imago - XL image scanner

Spectral scanner

Imago

Pros

Colorimetric precision

• The price is a fraction of that of a spectral scanner.

• Maximum versatility and ease of use by any graphics operator.

• High acquisition speed (typically 15 min/m2 for 600 DPI high-quality scanning).

• Optics and lights produced for more than 15 years by Seiko Epson, which has customer support centres all over the world.

• Standard Epson software for PC and OSX.

Cons

• Very high price.

• Light/shadow contrast not optimal.

• Low acquisition speed.

• Optics and lights produced in small quantities and difficult to find on the market.

• Need for custom software

A spectrophotometer is required to complete the workflow

From our experience at Intesa, we believe that a spectral scanner is not necessary in the ceramic industry. In all projects carried through using Imago (more than 100 in various factories), in the worst cases

the same results were achieved as with the use of a spectral scanner.

The ability to reproduce a material with precision, which is the key strength of a spectral scanner, becomes pointless if the designer has

to make colour variations or perform graphic design processing. In this case, because Imago is a traditional RGB scanner it can generate a more versatile if theoretically less precise input file.

CRONO DESKTOP 3 + SPECTROPRO – CERAMIC COLOUR MANAGEMENT

Crono is a system developed by INTESA. Imaging since 2009 for colour management in the pre-printing stages of the digital decoration process. Crono software facilitates the use of digital images and of design and production data in the various processing stages. It is particular-

FIG. 3 - Crono

ly suitable for companies looking to start up digital ceramic production as it offers them a quick and simple way of achieving a good level of colour quality while minimising the number of trials required before commencing production. Crono manages ceramic colour in xCLR mode, so it is in-

dependent of the CMYK model. This enables it to handle digital configurations with multiple colours (up to 8 or more), independently managing similar shades of colour on the machine. When interfaced with Imago and Colorscan 1010 it creates the ideal workflow for glaze and colour producers and for ceramic R&D laboratories.

Version 3 of the Crono system introduces an array of new features, all of which have been developed internally by the Intesa Imaging research centre.

The main changes come from the new Crono Image Library™ which forms the basis of all new Intesa software: Crono Desktop, Crono Production, Crono Cap and the operational software of DHD and DHW digital machines. Crono Image Library™ allows images to be processed with stateof-the-art technology, using the multithread and video card resources to

Acimac handbooks - 2014 Edition . 23

FIG. 5 - Crono: image acquisition of marble and stone

FIG. 4 - Crono: image acquisition of marble and stone

speed up all operations.

Improvements: • Up to three times faster over a complete workflow compared to the previous version.

• Video preview and other operations optimised for processing Sacmi Continua® and Continua+® line files.

• New CMYK and Multicolor profiler with proprietary mathematics and algorithms, compatible with 0/45° spectrophotometers (e.g. X-Rite EyeOne and Barbieri LFP) and d/8° sphere spectrophotometers (e.g.

X-Rite SP62/64 and Konica Minolta CM 2500/2600d).

• The reliability and size limitations of the plug-in for Adobe Photoshop™ for Windows have been improved.

• Improved connection with Tecnografica database.

• Improved HotFolder function with

FIG. 6 - Crono, profiling and separation

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halftoning capacity for complete automation of workflows with colour management and screening.

• Crono Image Library™ allocates computer resources intelligently to conserve RAM and to make maximum use of processors. Various strategies are used for small images or large sheets, including images larger than the computer’s physical RAM. • Auto Update function with automatic download and installation on request.

New functions: Advanced Ink Saving workflow • compatible with large profiles, with preview of results and information on savings.

• Complete management of PSD/ PSB and TIFF files with up to 11 alpha channels.

• Generation of test runs with automatic notes written on the tile.

FIG. 7 - Crono, advanced manual changes

• New Layout section with rotation, size change, cut and panelling functions; it is now possible to import a complete sheet and cut the sizes directly with Crono.

• Option with SpectroPro™ automated spectrophotometer to create perfect profiles on textured surfaces (e.g. Continua+®) and tiles with finishing glazes and grits.

• Advanced manual change with Intesa Tone Compensation™ function and other utility tools.

• Plug-in for Adobe Photoshop™ for Apple OSX. • Halftoning capacity with various algorithms and drop division parameters.

Management of “effects” and • “white” with levels sent separately to different machines (e.g. DHD+DHW project in a single file).

• Creation of master files for Crono Production 3.

FIG. 8 - Crono, production preview

The Spectro Pro spectrophotometer is recommended for use in ceramic laboratories and glaze and colour factories.

When a ceramic surface consists of glossy glazes, textures or finishes such as grits or protective glazes, it is very difficult for a normal 0°/45° spectrophotometer to read the colour accurately and repeatably. Incorrect measurements are detrimental to the generation of ICC profiles and impact on the entire Crono workflow, nullifying the benefits of soft proofing and adversely affecting image contrast. Spectro Pro is a Crono

option for automating integrating sphere spectrophotometers, which are normally used in ceramic laboratories for formulating coloured glazes and for reading linearisations and testcharts in difficult measurement conditions. Crono Desktop can make use of readings made by sphere spectrophotometers in both SPIN mode and SPEX mode.

FIG. 9 - Spectro Pro

COLORSCAN 1010 – CERAMIC PLOTTER

Colorscan 1010 is a compact and versatile plotter, ideal for research, development and prototyping activities in the ceramic sector.

The automation system consists of a Cartesian robot movement and ensures high printing precision.

The movements of the X axis (carriage movement) and of the Y axis (table movement) are powered by linear motors.

The Z axis movement (carriage up/ down) is managed by a stepper motor.

The graphics program allows

high-definition images to be printed in four-colour or multicolour mode.

Colorscan 1010 can be equipped with a maximum of 8 colour modules with the option of a further 8 modules on stand-by for rapid ink changing.

This means that up to 16 colour bars are available to simulate all the customer’s ink combinations with a high degree of precision. The bars can be interchanged to perform sequence tests to be replicated on the single pass printer. Colorscan 1010 can operate in “single pass emula-

tion” mode to reproduce the typical discharges of Xaar GS6 or GS12 printheads with multiple passes and achieve perfect, defect-free prototypes. For third fire production, Colorscan 1010 operates in “high discharge” mode, using multiple passes to deposit a greater quantity of colour than is possible in a normal single pass. These modes are managed using a special version of Crono Production, the software that functions as an RIP and adapts perfectly to the Crono Desktop graphic design firm workflow.

FIG. 10 and 11 - Colorscan 1010

Acimac handbooks - 2014 Edition . 25

GLAZING AND DECORATION IN THE DIGITAL AGE

Intesa is continuing along its path of technological development with the goal of complete digitalisation of the ceramic glazing and decoration processes.

For this purpose, it is unveiling a completely new range of digital printers marketed under the Sacmi brand name, demonstrating how its operations are becoming increasingly integrated with those of its Imola-based parent company.

For inkjet printing, Intesa is proposing its DHD series of decorating machines based on technology from Xaar, the world leader in inkjet technology.

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The DHD series can be fitted with all types of Xaar 1002 printheads, including the brand new GS40 heads unveiled at Tecnargilla 2014.

DHD printers offer a number of major improvements and innovations over previous versions of Intesa machines. In particular, the ink circulation and feeding systems have been entirely redesigned to ensure a very high level of performance.

The electronics are also completely new. All Intesa machines now use proprietary electronics developed internally by the Sacmi Group, which ensure very high performance in terms of data transmission rates,

manufacturing flexibility and reliability, while at the same time allowing for perfect integration between the various digital applications that are to be found today on a ceramic glazing and decoration line.

Furthermore, the DHD printer management software has a simple and intuitive graphic interface that is easy to use by operators.

The DHD digital printer range comprises models DHD708 (maximum printing width of 697 mm), DHD1108 (maximum width 1120 mm) and DHD1308 (maximum width 1390 mm).

Alongside these models, which can be used to decorate all sizes up to 1200 mm after firing, Intesa is also proposing a digital printer version that has been specially designed for decorating very large format ceramic panels and for installation on Sacmi’s Continua+ production lines. With its maximum printing width of 1882 mm and the possibility of installing up to 8 colour bars, the DHD 1808 has technical, construction and functional characteristics that are intended specifically for integration with the Continua+ production cycle.

Equipped with an individual cleaning system for each colour bar, the DHD 1808 can be programmed to per-

form bar washing cycles in the time between the passage of one tile and the next, without the need to halt production.

In view of the extraordinary benefits that digital technology offers for the decoration stage, the entire ceramic sector is striving to expand digital applications.

In particular, special materials are being used to bring new aesthetic possibilities to the traditional decoration process, including increasingly rich natural textures, colours and effects. However, as these materials are still solvent-based and have a sub-micron particle size, they often have the drawback of high costs and limited application potential.

To be able to produce tiles with the

real material look and feel that cannot be achieved using inks alone, Intesa has developed the new HW printing technology for controlled application of ceramic glazes.

HW technology can apply water-based glazes with particle sizes greater than 3 microns (range 3 - 12 micron). It is capable of depositing glazes in quantities of between 200 and 1000 grams per square metre for either full-field applications (engobes, textures) or specific spot applications integrated with traditional ink decoration.

Initially designed and developed in the Sacmi Group’s research laboratories, HW is now brought to the ceramic industry by Xaar with the brand new Xaar 001 print-

head, featured on Intesa’s Glazejet and DHW series digital printers.

The Glazejet 330 laboratory plotter, complete with a printing station and DropWatcher system, has already been adopted by numerous glaze and colour producers for their glaze research and development activities.

The Glazejet 1000 plotter is suitable for prototyping and developing large-size products.

During Tecnargilla 2014, Intesa also unveiled the DHW 700 digital printer, the first single-pass digital machine for operation in a continuous industrial process. DHW can be synchronised with conventional inkjet printers and allows a fully digitalised glazing and decoration line to be created.

NOTES

Acimac handbooks - 2014 Edition . 27

The infinite potential of the digital revolution

by Vincenzo Palumbo

Projecta Engineering believes that digital decoration is very different from using a photocopier.

The digital process is capable of much more than turning out standardised products at competitive prices or producing aesthetically perfect copies of wood or marble that have limited added value.

The digital revolution is so profound that a complete overhaul of the system is required.

Importantly, this revolution does

not involve a loss of skills, which instead are simply shifted from the decoration line to the graphic design studio.

To create a unique and inimitable product, the graphic design studio plays a key role in providing the initial input and giving an overall shape to the project.

The mission embraced by Projecta Engineering and Digital Design is to improve customers’ knowledge of digital technology and its potential

and of the infinite range of decorative solutions that can be achieved.

This is primarily a cultural operation, an investment that the company has chosen to make to promote full awareness of the potential of digital decoration lines and their ability to improve competitiveness by delivering aesthetically high quality products at a moderate price and giving free rein to creativity.

THE DIGITAL DECORATION LINE

EvoMOVING

Projecta Engineering provides everything necessary to create an integrated digital decoration line, from graphic design and development of the original project through to the finished product.

As a “digital native” company, Projecta Engineering not only supplies the machine but can also provide support in designing and developing a fully digital decoration line.

The essence of Projecta Engineering lies in its overall vision of the process.

The advances in technology must be backed by a “digital culture” that is capable of determining the best use of new technology suited to any kind of custom solution (glazing, application of special materials, dry decoration, effects and complex processes).

With the digital process, a one-off plant investment can be optimised to obtain an unlimited range of products.

An innovative design idea immediately becomes a real, concrete opportunity, without additional costs and investments.

The graphic design is always the main focus. Projecta Engineering is also able to steer the technological development of printheads and

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printing inks in the short to medium term thanks to the electronic system and print management software developed and produced internally.

Thanks to its knowledge and technical expertise, Projecta Engineering is able to offer all the major technological solutions available on the digital decoration market.

These include compact, modular machines with a large printing width that guarantee extremely high flexibility and rapid colour change, smart maintenance, custom printers and printers specially designed for decorating trim pieces.

Projecta Engineering’s decision to avoid pointless superstructures right from the design stage together with its knowledge of the methods and needs of the target sector mean that its machines are extremely simple and user friendly.

Tailored to the needs of a dynamic and rapidly developing sector, Evolve machines are designed and built with a view to the future and are therefore capable of incorporating the research work and innovative proposals of other players such as ink manufacturers.

THE ADVANTAGES OF EVOLVE DECORATING MACHINES

Through a process of ongoing research, Projecta Engineering has transformed decoration into an efficient, high-performance digital system that can be fully integrated into the production process. A design approach that aims to establish an effective dialogue between all stages of the glazing line has resulted in intelligent, fully automated lines centred around the graphic design project.

The use of cutting-edge solutions (Evolve, Evostore, Synchro 3D, Evovision) has already produced outstanding results in terms of maximum integration of digital technologies into ceramic production lines. Following the addition of new models and accessories, the Evolve family is now the most complete and versatile range of decorating machines on the market.

The main advantages of Evolve digital decorating machines are: - compactness, ruggedness and versatility; - ease of access and maintenance thanks to the automatic cleaning system; - powerful suction;

- machine parameter management from a single point; - low installed power; - speed of loading images and changing graphic design; - fully interchangeable colour modules; - modularity and scalability according to customers’ requirements.

decided to extend its already wide range of extra-large printers with the introduction of the new EVO 8, which has a printing width of 1890 mm. It is the first company in the sector to have introduced a machine capable of decorating such wide ceramic panels.

Evolve decorating machines have very small overall dimensions and class-leading characteristics. Their proprietary hardware and software architecture allows for the use of a range of printheads. An open system of this kind brings significant benefits as there are no constraints on ink and printhead purchasing, allowing for the utmost freedom of choice.

Projecta Engineering unveiled a number of new products at Tecnargilla 2014 including the digital machine with the largest printing width in the world, which is already in operation at the facilities of two leading Italian ceramic manufacturers. In view of the market success of large format tiles and their growing use in unconventional applications, Projecta Engineering

EVO 8

EVODRYFIX

Another innovation is that of EvoDRYFIX, a machine for dry powder application already in operation at several factories in the Sassuolo area.

EvoDRYFIX is the first digital ceramic printer to combine inkjet drop on demand technology with dry application technology. The system is able to apply grits in a range of particle sizes from 50 microns to 500 microns according to a precise digital design that can synchronise perfectly with the design of the decoration inks.

This means the system can perform any kind of application, from high-definition, low-thickness applications through to coarse, highthickness applications.

It guarantees maximum stability and repeatability of granule application. As with the entire Evolve family of decorating machines, the EvoDRYFIX stands out for its exceptional flexibility of use.

The granules can be changed in a short space of time to allow for a rapid reconfiguration of the decoration line.

EvoDRYFIX Acimac handbooks - 2014 Edition . 29

EVOSTORE

EVOstore is a wheel-mounted storage unit containing from one to five colour trays, which are fed and managed by a dedicated electronic system in an air-conditioned envi-

EVOstore

EVO7

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ronment.

It meets the need to enhance digital tile decoration using the entire range of inks currently available on the market, no longer limited to the CMYK colours of the traditional four-colour process but increasingly enhanced with new colour spots and material effects. Inside EVOstore the trays complete with printheads temporarily on standby are fed continuously and cleaned automatically. The colours they

contain are kept circulating ready for use at the required operating temperature.

The system is ideal for storing trays containing spot colours that lie outside the four-colour range or material effects such as lustres, metallised, white and sink-in glazes, which can be used interchangeably on different machines. Evostore is the natural complement to the Evolve/Evolve Plus series digital decorating machines.

NOTE

Acimac handbooks - 2014 Edition . 31

Advanced colour management solutions for ceramic digital decoration

by Silvano Filippi

The rapid growth of digital ceramic decoration technologies has brought considerable benefits for the tile production process worldwide.

Because of their complexity, however, these technologies must be managed effectively in order to make best use of digital decoration systems and to optimise the timeframes and costs of research and production.

The initial approach to colour management, which was derived from the paper printing sector and involved adapting graphic design applications and performing subsequent testing, is now obsolete.

The availability of an ever wider range of printing systems and inks, the numerous variables associated with the greater number of printing bars and the introduction of coloured bases with decorative effects have brought major changes in terms of colour

management requirements. The following are the most significant: 1) The use of non-proprietary colour management software solutions that are not restricted to a specific brand of printers.

2) Optimised printing for an increasingly varied collection of inks that are ever more distant from conventional four-colour printing, often in conjunction with coloured glazes.

3) The ability to print a product on lines equipped with different printers and inks and adopting various firing conditions but with the certainty that the same end result will be achieved.

4) To reduce research times by

using high-performance acquisition systems and high-fidelity onscreen or printed previews to be able to determine the end results of image processing right from the outset.

To meet these needs, the Smaltochimica group’s subsidiary Colourservice has launched a hyperspectral scanner acquisition technology and a colour management software called ColourProfiler specially for the ceramic industry.

The hardware and software has been developed from scratch using solutions tailored specifically to the ceramic industry rather than trying to adapt systems originally designed for the paper or textiles sectors, which have a number of aspects in common with the ceramic industry but also many differences.

HARDWARE SOLUTIONS

Colourservice has further optimised its spectral acquisition system with the introduction of a new image acquisition system with large acquisition dimensions (up to 100x100

FIG. 1 - Spectral scanner 1000

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cm) and a range of resolutions capable of meeting the everyday needs of the ceramic industry.

The scanner is a full-scale spectral

system based on sphere (or 0° diffused) measurement technology, a technique that has been used highly successfully in the ceramic sector and was originally introduced by the Smaltochimica group with its portable spectrophotometers (SP62).

This instrument, integrated with a colour matching system, has been used for reproducing models since the time of ceramic decoration with silicone rollers.

The solution is designed for customers wishing to develop graphic designs internally or who base most of their work on third party reproductions of existing projects.

In a single acquisition, the spectral scanner is capable of obtaining not just the graphic file of the scanned object but also all the reflectance values of the various tones. Subsequent processing can produce a profiled graphic design project ready for printing which can be previewed on calibrated monitors.

A paper preview can also be made by calibrating a photographic printer and integrating it into the colour management workflow.

All output devices and graphic profiling of files on these devices are managed using our colour management solution.

SOFTWARE SOLUTIONS FOR COLOUR MANAGEMENT

Our colour management solutions serve as the cornerstones of a digital laboratory.

They were developed by a team with extensive experience in the ceramic industry using constantly evolving proprietary algorithms to meet the current needs of the sector.

The software can display and process graphic design projects and mathematical formulations developed according to the specific needs of the ceramic industry.

Colour Profiler (photo 2) is a complete colour management system intended to help ceramic sector graphic design technicians develop and correct graphic design projects for inkjet printing.

Its ability to manage all printers, inks and coloured bases makes it the perfect tool for profiling new designs, whether they are based on our proprietary acquisition system or other conventional systems (RGB scanners, cameras or camera backs) or were supplied by graphic design firms or glaze and colour producers.

Colour Profiler achieves clear time savings right from the start.

The possibility of previewing the final result on screen or on paper enormously reduces the number of tests needed to achieve a given result. This enables the ceramic graphics laboratory to focus its efforts solely on products that guarantee a finished result that will meet the needs of the market and satisfy the requests of the marketing department.

in such a way as to correct designs that display variations during a production cycle.

These functions can considerable reduce the quantity of non-compliant products and production stoppages.

This software solution also improves planning and makes for better use of ceramic resources by helping the graphics laboratory transfer a product developed in one printing context to a different one (for example a different factory, a currently underutilised production line, a new printing system or a new set of inks).

This function, known as “device link�, allows for considerable freedom of planning and avoids obligatory production choices.

Colour Profiler can quickly and relia-

bly determine the feasibility of transferring a graphic design project to a different printing context based solely on the source and target colour profiles.

All processing operations allow the user considerable freedom of operation while ensuring a high-quality end result and optimising consumptions due to the new individual and total ink limitation functions.

The Colour Profiler software is not only associated with the hyperspectral scanner but can also be combined with various commercial measuring instruments for measuring colour patches.

This enables even small and mediumsized ceramic companies to adopt the most advanced complete colour management solutions in their

FIG. 2 - Workflow with Colour Profiler

But Colour Profiler can do more than create new files.

It can also help the graphics laboratory alter an existing printing file Acimac handbooks - 2014 edition . 33

workflows.

To be even more useful for the ceramic industry, the software contains functions for comparing the colour profile (gamut) and individual inks so as to be able to evaluate and analyse them immediately.

Although the software was developed specifically for the ceramic industry, it is compatible with the require-

ments of graphic arts, allowing it to create colour profiles (ICC) that can be used in graphics processing applications such as Adobe Photoshop.

The application can be installed on standard workstations, enabling the various databases to be saved on a shared platform and allowing many different users to work at the same time.

SOFTWARE SOLUTIONS FOR DATA STORAGE

In traditional decoration systems, the storage of manufacturing data and retrieval of a model for a new production run were never insurmountable problems.

The storage systems themselves were relatively simple.

New production runs could be started up simply by using a technical data sheet kept in the laboratory. Fol-

lowing a couple of trial runs and a few corrections, it was possible to reproduce the model based on the original standard with a high degree of precision (photo 3).

The advent of digital decoration has changed all of this, focusing on an aspect that tended to be neglected in previous technologies: the volatile nature of projects.

Graphic projects and their implemen-

tation now consist of a sequence of bits that are at risk of being lost, damaged or stolen.

tional sequences - are not stored effectively, it becomes extremely difficult to reproduce a standard model.

And if the stored data is incomplete, a lot of work is needed to recover the original files (photo 4).

FIG. 3 - Traditional decoration: project management using physical printing templates

FIG. 4 - Digital decoration: project management using software solutions

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. Acimac handbooks - 2014 edition

If all the production data - including variants, modifications and opera-

To tackle this problem, Colourservice has partnered with a leading player in a non-ceramic sector to develop a ceramic version of its file storage application.

This client/server solution provides the ceramic graphics laboratory with a precise storage system, which can be used to hold original

products along with all the variations and corrections that have been made and information on which operator has created or modified the designs and the sequence in which these modifications were made. The system provides a simple backup of products and guarantees traceability, thus protecting

against the risk of loss, overwriting or incorrectly assigned changes.

Smaltochimica group believes that tools for controlling digital printing must become a top priority for ceramic companies as they enable digital technologies to be managed with ever greater autonomy.

The Smaltochimica group and Colourservice The Smaltochimica group is a leading company with more than thirty years of experience in the ceramic chemicals sector and has branches in all the world’s major ceramic manufacturing areas.

As part of its ongoing research and innovation efforts for the benefit of customers, Smaltochimica has set up Colourservice, a new company in the field of ceramic colour management which develops and uses unconventional technologies to help customers optimise and improve the efficiency of digital decoration. www.smaltochimica.it www.colourservice.net

NOTES

Acimac handbooks - 2014 edition . 35

Breaking the paradigm of submicron ceramic pigment suspensions During many years it was widely accepted that ceramic pigments could not be ground into the submicron range (d99 < 1 µ) without a relevant loss of colorimetric and other physical properties.The wide spread use of wet grinding technologies, lead to extremely long times before finer products were to be produced.

During this long grinding process pigments were certainly damaged in

certain degree leading to the mentioned paradigm of “ungrindibility” of ceramic pigments below 1 micron.

The introduction of ceramic inkjet using drop on demand printing technologies pushed the technologic leading companies in the field of milling to develop a process, based on the optimal combination of Dry + Wet grinding techniques, to obtain suspensions of ceramic pigments in

the sub-micron range (d50 0,15 µ 0,3 µ / d99 0,6 µ - 0,8 µ).

Over 45 Mio kgs of ceramic inks supplied and more than 3000 ceramic digital printers worldwide confirm that this goal was achieved successfully, breaking that paradigm and opening new and challenging fields for grinding ceramic raw materials, glazes and other related products.

NETZSCH SOLUTIONS FOR CERAMIC APPLICATIONS

Since the first batch was run on a LABSTAR laboratory mill in December 2005, NETZSCH has accompanied the development of inkjet technology and has been at the forefront of this technology.

This is confirmed by the hundreds

of NETZSCH machines producing ceramic inks and other ceramic applications all over the world.

Through its vast experience, NETZSCH is able to develop and select the best solution for every single step of the process (pig-

ment processing, mixing, wet grinding, etc.) in the production of digital glazes and inks, ceramic pigments, InGlass ceramics inks, technical ceramics, minerals and raw materials and ceramic masses.

FIG. 1 - Zeta 400

WET GRINDING - ZETA® SYSTEM

Among the nine wet grinding systems available in the NETZSCH

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. Acimac handbooks - 2014 Edition

product portfolio (horizontal disk mills, basket mills, vertical mills,

etc.) ceramic inkjet pigments manufacturers have chosen the ZETA® Sy-

stem because it offers clear advantages: Very narrow particle size distribution that is easier to control (filtering capability, color intensity, etc.); highest level of productivity; total reproducibility of the results and fewer grinding beads required.

ZETA® System is designed with a smaller grinding chamber (about half the size of that of a disc mill, comparable energy input), a model for circulation mode and agitator pegs for the greatest efficiency.

Recently, NETZSCH has launched

the largest mill in recirculation ever built, capable of processing up to 10,000 liters batches.

It completes the mill range as for chamber sizes, from the 0.62 lts LABSTAR laboratory mill to the 400 lts LMZ ZETA® 400.

DRY GRINDING

As for dry grinding, a correct formulation and fineness of the ceramic pigments is essential to achieving a color with a narrow, controlled particle size distribution. NETZSCH offers two solutions: • CGS Fluidized bed jet mill with ConVor® classifier wheel for narrow particle size distribution to d97 <4 µ - 5 µ • and S-JET® Steam Jet mill.

The S-JET® Steam Jet mill technology is an advanced development of the NETZSCH-CONDUX Mahltechnik Gmbh well known Air Jet mill, using high pressure overheated steam instead of air as grinding media.

The use of steam offers a much higher impact velocity as well as a completely new possibilities in the classification process, leading to fineness never seen before in the ce-

ramic pigment industry (a very narrow particle distribution curve down to d50 ≈ 0,45 µ / d97< 1 - 2 µ).

The use of such fine and narrow distributed pigments into ceramic inkjet inks has a direct influence in very significant decrement of the wet grinding time.

Apart from the obvious consequences of optimizing the bottleneck of the process, and energy cost reduction, even more important advantages derive from the shorter wet process of the ink: It is a well-known that wet milling using micro-beads below 0.5 mm creates an increasing amount of ultrafine particles of pigment into the final ink, which has a very negative effect in colorimetric, rheological and reactivity of the ink and has been a constant nuisance for the develo-

pers of ceramic inkjet inks.

The narrower pigment curve from the S-JET®, together with the shorter wet grinding times, results into a much narrower curve of the ink with less ultrafines and therefore color strength (especially in yellow and red brown inks).

This will set new standards in the digital decoration of ceramic tiles.

Cost reduction and increase of ink quality will give a competitive advantage to companies adopting the SJET® dry grinding technology.

On top of that, this new dry grinding technology has opened new manufacturing possibilities in the field of tile manufacturing and decoration, such as digital glazing and “simultaneous” drying and grinding of ceramic slurries in the submicron range, etc.

NETZSCH worldwide NETZSCH operates, in the truest sense, in close proximity to its customers. Currently have production facilities in Germany, the USA, Brazil, Russia, India and China. There, where new markets are taking root, to ensure that customers receive support and guidance on the spot.

In a globally-organized regional sales network, NETZSCH guarantees that you will always be working with highly-qualified NETZSCH specialists. This means that you will receive guidance and support locally from NETZSCH specialists in the areas of sales, service, design and process engineering.

Always a step ahead - for more than 100 years Business division Grinding & Dispersing is part of a strong, family-owned enterprise established in 1873, whose philosophy calls for quality leadership in every regard. All three business units of the NETZSCH Group - “Analyzing & Testing”, “Grinding & Dispersing”, “Pumps & Systems” - meet these requirements. Our customers have made us what we are today: internationally soughtafter specialists for everything related to the areas “wet and dry grinding”, “mixing and dispersing”, and “de-aeration and classifying”. Constantly changing demands have led not only to a comprehensive range of machines, but primarily to a unique pool of applications and processing knowledge.

This puts us in the position to make the visions of our customers a reality - unbureaucratically, innovatively and economically on into the future. You set the specifications, we make the machines.

Acimac handbooks - 2014 Edition . 37