TODAGRES, under its new product type with the brand name TODATECH, has managed to combine the appearance, beauty, and depth of natural stone, wood, and cement, with technical characteristics inherent to its base material, high-traffic technical porcelain, resulting in a truly innovative product.
Made with an innovative technology, the variety of its pieces, as well as its high definition, allow for effects and functionalities never achieved until now.
It is the new brand by TODAGRES, which combines products manufactured with high-definition penetrating soluble salts technology, so that all products in this series are high-traffic technical porcelain, both in their Natural and Polished versions.
With this technology we can manufacture materials of varied typology such as marbles, woods, slates, cement… it is, therefore, a great progress for the future of TODAGRES. Its main characteristics are:
HIGH TRAFFIC TECHNICAL PORCELAIN
POLISHED WITH GLOSS HIGHER THAN 85%
EASY CLEANING (LEVEL 5)
MOSH 5 O SUPERIOR
HIGH CHEMICAL, MECHANICAL, AND STAINING RESISTANCE
TODATECH is manufactured with state-of-the-art technology digital printing machinery, developed specifically to make technical porcelain material with high-definition graphics.
The polished finish ensures a surface gloss of 85%, similar to that of polished crushed frits, and far superior to polished marble. The result is also a maximum value on the scale of ease of cleaning (level-5.)
VS POLISHED CRUSHED FRITS
Resistance to scratches (MOHS), which for polished crushed frits is a coefficient-3 or lower, in the case of our material it is a coefficient-5 or higher, equal to that of polished technical porcelain, which makes it a material suitable for high traffic.
Our material cannot be damaged by acids (e.g. lemon,) while to polished crushed frits CAN be damaged by these products, leaving hard-to-remove stains.
VS NATURAL STONE
It has a scratch resistance (MOHS) with a coefficient-5 vs. the coefficient-3 of marble.
It is a material that is not damaged by acids (e.g. lemon;) in contrast natural stones can be damaged by this type of product, leaving permanent stains.
The ease of cleaning, which for marbles is of level-3, is of level-5 for TODATECH (this represents the maximum level of the ease of cleaning scale.)
The surface gloss of a polished natural stone is 70%. However, the polished TODATECH material has an 85% gloss.
The water absorption of natural marble is approximately 1%, while that of TODATECH material is less than 0.1%.
In order to obtain a perfect understanding of TODATECH, we recommend watching our 3-minute-long explanatory video on our web page.
1 – OBJECTIVES
We could summarize our objectives as the obtaining of technical porcelain stoneware ceramic tiles that significantly enhance their aesthetic attributes, while maintaining their technical characteristics and performances at the same time, thus providing them with qualities that without a doubt will be of great interest for the Ceramic Industry.
In order to do this the development – internal in this case – of a new decorative technique that allows a definition, chromatic variety, and color development never accomplished before with this type of product, has been necessary, both for its natural and polished finish, and taking advantage of digital technology.
2 – INTRODUCTION
In its early stages, and up until relatively not too long ago, technical porcelain was known as a monochrome product, generally produced in small format. In fact, in its earliest origins (1865), the products manufactured by businessman Miguel Nolla at his factory in Meliana (Valencia) had a palette made up of nine colors, where the metric used for the tiles (1.5 x 1.5 inches) confirmed their English origin: white, beige, light gray, medium gray, brown, black, red, blue, and orange.
Later, with the course of the years, applied research permitted the individualization of typologies that made possible the aesthetic enhancement of the product, with interesting and diversified results. The mixture of colored granules allowed to obtain valuable products, commercially known with the name of “granitos” (grains) or “sal y pimienta” (salt and pepper.)
From the 1990s, new decorative techniques begin to develop, which become a priority objective in the innovation of this product. Some of these techniques were adapted to production, such as press decorations with “double load” carts, regranulations, scales, reliefs, etc., while it is true that each new development required a strong investment in machinery by the manufacturer that was not always rewarded with sales.
Thus, even though the aesthetic qualities of technical porcelain attained dimensions of extraordinary beauty not too long ago, it is no less true that the are in decline nowadays, so that the emergence of a new technique that allows the enrichment of decorative motifs, such as the TECNOLOGÍA TODATECH that we present in this 41st Edition of Alfa de Oro Awards granted by the Spanish Society of Ceramics and Glass in this Cevisama 2017 competition, will be well received.
3 – EVOLUTION OF THE TECHNIQUES USED IN THE MANUFACTURE OF SOLUBLE-SALT-DECORATED PORCELAIN TILES
3.1 – FLAT SCREENS (version 1.0)
In this section we refer to the traditional technique of flat silkscreen printing which consisted in the manufacture of a perforated fabric that was fixed on a frame to make up a printing screen. A soluble ink would be spread on it, which would be pushed through the holes with a scraper, thus leaving the screen design on the tile.
Once the soluble ink was applied on the support, it would require the application of a penetrating agent using an airbrush to achieve the required penetration of the ink and obtain a ‘good’ definition of the design after the polishing stage. Lastly, a dryer would stop the migration of soluble salts towards the inside of the tile.
To achieve optimal results in the finished product (polished,) it was necessary to work with low-thread fabrics (54T, 45T, 38T), thus achieving more release weight, which did not favor good aesthetic results at all due to the lack of definition.
In addition, the fact that all the pieces were equal, since only one image could be applied, and also due to the proliferation of hues after polishing – problems associated both to the penetration of salts and to the polishing operation itself, where rollers and heads reduce the thickness of the tiles up to 1.0 mm – resulted in that this technique did not quite establish itself as an decoration alternative.
We will also mention intaglio printing technique in this section. It uses a roller that has small surface openings that define the design to be transferred to the tile. These holes, created with laser, are small and allow a greater image definition than printing screens.
Tiles obtained with this method had minor variations in decoration, depending on the surface of the roller and the position it is in when it comes into contact with the tile. In spite of this, the repetition of the decorations is limited by the surface of the roller.
It also needed the application of a penetrant with airbrush, and the final results, in terms of definition and color quality, were similar to those of the flat screen, and this technique also went into disuse.
3.2 – DIGITAL DECORATION (version 2.0)
In this section we will talk about the appearance of the ink-jet.
At the end of the 20th century, a form of decoration using digital printing technologies was established in the Ceramic Industry, which allowed to decorate ceramic tiles with photographic quality, as was the case in other sectors; these technologies completely changed the ceramic decoration spectrum by establishing the no-contact principle between the piece and the head.
With this technology, the design is created, modified, transported, and applied digitally, eliminating the use of intermediate elements (films, screens, rollers, etc.), which facilitates testing or changes in designs, and reduces the generation of waste as there is less handling of chemicals.SInk management is simplified, which reduces the amount of inventories and warehouses, the product customization is simple, and it requires reduced but specialized labor.
This technique is born with soluble-salt inks as the pigments must present submicron particle sizes (because the diameter of the holes in the inkjet heads is very small,) thus preventing the nozzles from clogging.
It is estimated that the ink particle size should be at least 20 times smaller than the diameter of the nozzles, something unthinkable at that moment with traditional pigments, and which was only achieved years later, being nowadays a technology that is greatly developed and present throughout the world.
However, the poor color development of soluble salts on normal ceramic tile supports was the cause why this technology did not go ahead either.
Nowadays manufacturers find that we are not able to decorate technical porcelain products with chromatic richness, with the nearly photographic definition with which a vast number of glazed porcelain models are being developed using pigmented inks, and hence there is a need to develop a technology capable of combining these two premises.
3.3 – TODATECH TECNOLOGY (version 3.0)
The development of this new technology involves two essential elements:
• The Paste.
With the use of traditional pastes, it became clear that the chromatic performance of soluble salts was very limited, so we initiated a study at TODAGRES aimed at trying to improve this poor color performance.
As a result of this study we discovered that certain additives added to the paste increased the chromatic performance of colors considerably. Very specific additives were identified, each of them improving the development of a certain color; we currently have a specific additive for the development of yellow (based on Chrome) and another one for magenta (based on Iron)
Once the deficiencies were identified, the solution was easy: adding these additives to improve chromaticity. However, when putting this solution into practice, adding them to the mass, the costs of the paste soared, making this procedure unfeasible.
As an alternative, we thought of applying this ceramic composition with additives as a double load in the presses, but again the cost issue emerged as a problem, not only due to the high consumption of additives, but because the double loads reduce the speed of the presses to less than half. The final cost was still not competitive.
After a new study aimed at finding a solution that would not penalize the cost of the final product, we chose to design a PREMIER (slip) for wet application without any frit.sThis technique lets us have sufficient layer thickness to apply the soluble salts, obtain an immensely improved surface chromaticity, and put the cooked pieces through the necessary mechanical treatments to offer the finishes that the market demands, including polishing.
NOTE: Unlike what happened in the flat screen stage, because during the polishing state the intervention of rollers or diamond radial heads was not necessary, the PREMIER, with a thickness of less than 300 microns, is enough for obtaining excellent results with soft diamond abrasives, thus minimizing the proliferation of hues associated with soluble salts.
In addition to selecting and optimizing the used products, we have also had to work on their application, which is carried out, as one
would expect, with the inkjet machine.
To achieve ink penetration we would apply a penetrant in the traditional way, with an airbrush. We thus achieve a precise penetration, but on the other hand we obtain poor definition because the airbrush application smudges (blurs) the graphics.
Once again we had to carry out a study aimed at improving the application conditions of the penetrant to optimize the graphic definition. After opening several fronts, we finally opted for carrying it out through the heads of the inkjet machine itself.
After quite a few attempts, we obtained what we were looking for: an excellent definition without loss of penetration of the different inks thanks to a treatment carried out using Photoshop, pixel by pixel, where the weights placed on each ink are digitally compensated.
4 – EVOLUTION OF THE CHROMATIC DEVELOPMENT
The application of soluble salts on a traditional technical porcelain tile paste has a chromatic limitation as we can see in fig.1. It is clearly evident that most hues are in the greenish-yellow and greenish-blue range.
If instead of applying these salts on the traditional support we do it on the PREMIER with the color enhancers, we obtain a considerably greater chromatic range, as can be clearly seen in fig.2.aThe chromatic range is quite different here, being able to appreciate the emergence of beige and brown hues in tests carried out with yellow, cyan, and magenta inks (from Fe.)
If we add one more ink (gold magenta, image 3), we see a greater chromatic richness, and if we finally add another ink (ruthenium black, image 4), we have a unique color palette that could well be the embryo of a new era where technical porcelain occupies once more the place that it rightfully deserves.
5 – CARACTERÍSTICAS FISICOQUÍMICAS.
The Institute of Ceramic Technology (Instituto de Tecnología Cerámica) is making a new physicochemical characterization of tiles manufactured with this new technology, the reports of which we will present the day of the defense at the Alfa de Oro Awards.
In any case, the results obtained to date only confirm that products manufactured with this new technology maintain the excellent physicochemical properties and performance of technical porcelain tiles.
6 – BIBLIOGRAPHY
• “Decoración del gres porcelánico natural con aplicaciones de naturaleza organometálica”.J. Portolés, J. Sánchez, C. Soler, D. Redondo
• “Decoración del gres porcelánico con sales solubles”. I. Piccinini, M. Burgoni,
• Estudio de la adsorción de tensoactivos poliméricos sobre pigmentos cerámicos en medios orgánicos. Master Universitario de Marta Rodrigo Edo, de la Escuela Superior de Tecnología y Ciencias Experimentales del Departamento de Ingeniería Química.
7 – CONCLUSIONS.
• We have identified a series of specific additives that added to the ceramic compositions enhance significantly the color performance of soluble salts.
• We have developed a technology (PREMIER) that lets us use these additives at a reasonable cost.
• We have reprised digital technology so that the technical porcelain can compete on equal terms with pigmented inks, dividing by ten the weights used with the old flat screens, and drastically reducing waste.
• Applying the penetrant with the injection machine lets us customize its release on each ink pixel by pixel, optimizing its penetration and definition.
• Penetration, which is only a few decimal points, reduces the intensity gradient and minimizes the proliferation of hues during the polishing stage, thus not requiring diamond rollers or radial heads.
In conclusion, TODAGRES has developed a new decorative technique with soluble salts which allows, with a reasonable cost, for a definition, chromatic diversity, and color development never before achieved with this type of product, thus enabling the revival of technical porcelain.