Innovative approach for the digital ceramic tile glazing process, using a continuous inline glazer

Project Information

Glazetile

Grant agreement ID: 101007342

DOI

10.3030/101007342

Project terminated on 8 February 2022

EC signature date 1 October 2020

Start date 1 November 2020

End date 31 October 2022

Funded under

• PRIORITY 'Societal challenges

Total cost

€ 1 974 781,25

EU contribution

€ 1 382 346,88

Coordinated by

TECNO ITALIA SRL
Italy

Periodic Reporting for period 2 - Glazetile (Innovative approach for the digital ceramic tile glazing process, using a continuous inline glazer)

Reporting period: 2021-11-01 to 2022-10-31

Summary of the context and overall objectives of the project

Current glazing technology (spraying) is a highly polluting and toxic process, poisoning workers with silica and ceramic dust in ceramic tile industry worldwide.
Glazetile is the first family of digital ceramic tile glazers: DigiGlaze & DigiGraphic. They target respectively the 2 glazing steps of ceramic tile manufacturing lines for an in-line deposition of fully water- based glazes through digital printing process with a precise definition of the printing area with the consequent elimination of glaze losses (~40wt%). It produces zero pollution and toxicity process, by eliminating 100% of wastes and avoiding the dispersion in the working environment of solid particles and dangerous vapors deriving from the use of organic additives, widely used with current production technologies. DigiGraphic aims the structuring of ceramic tile surfaces by a digital application, eliminating the use of highly costly structured dies in the presses.
Glazetile is perfectly aligned with the European Green Deal, under the topics “Transitioning of industry to a clean and/or circular economy” and “Realizing a zero-pollution ambition and a toxic free environment”.
TecnoItalia (TI) unique features are: first continuous ceramic tile glazer that uses fully water-based suspensions; no pollution, no toxicity; elimination of suction cabins, aspiration systems, air filters maintenance and cleaning issues; efficient process in terms of energy, water consumption and sustainability; increased quality of glazed surfaces with stronger colors and reduced roughness.
The overall objectives can be summarized as:
o Improvement of the working environment in ceramic tile factories
o Elimination of the glaze waste (~40wt%) through a digitally deposition (circular economy)
o Enhancement of the quality of glazed surfaces: by increasing the intensity of colors +10% in the CIELab scale and by reducing the roughness up to 50%
o Production costs reduction: 25-40%
o in the case of DigiGraphic, elimination of highly expensive structured press dies by a relatively low-cost and flexible digital process, increasing the productivity, flexibility and quality of the process.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the duration of the Glazetile project, the achieved results were even higher than expectations. In this period, experimental activities were carried out aimed at verifying the critical points in the construction of the two printers (DigiGlaze and DigiGraphic), as envisaged in the Glazetile project (WP1, T 1.3 definition of the final layout). Feedback from clients of beta test printers and the analysis of failures (FMEA) were helpful for the enhancement of the printers’ performance. CFD simulations were also carried out for the accomplishment of this task.
DigiGlaze is for the continuous deposition of engobes/glazes to obtain full coverage of the tiles. DigiGraphic is for the deposition of engobes/glazes for decorative purposes through structuring the surface of the ceramic tile with three-dimensional features that can reproduce the appearance of natural materials, as stones, woods, marble, etc. TI divided the development into two areas: one was focused on DigiGlaze operation mode definition, by comparing Continuous Jetting Mode (CJT) and Drop on Demand (DoD) technologies. In particular, significant efforts were addressed to the development of the DoD print-head bar. The work on DigiGraphic was mainly to verify the functionality and durability of the electrovalves (Evs) employed and to individuate alternative routes for the digital structuring of tiles. In particular, a new technological solution emerged for the structuring of tile surfaces during the period.
DoD technology demonstrated to be the most flexible, permitting to obtain a very precise and uniform deposition of smaltobbi, glazes and engobes having very different compositions and rheological behaviors. Compared to spraying technology, the most consolidated in the sector, immediate advantages are obtained as very high savings in terms of glazes, water, energy and plant engineering and the elimination of atomized ceramic materials and other organic-based contaminants, dramatically reducing the problems of health of operators and environmental contamination in a broad sense. The basic structure of the machine consists in a patented electro-mechanical drop dispenser system forming the DoD print-head bar, in which numerous nozzles are inserted, controlled by a specific numerical control. In the case of DigiGraphic, the initial design idea, a bar consisting of a series of nozzles and solenoid valves controlled singularly by the control system, was replaced by a system consisting of two application bars. By doing this, the resolution of the printer was enhanced from 25 to 200 DPI.
Furthermore, during the first 14 months, three important additional auxiliary equipment were designed to complement the printers. A double tank was designed to control the glaze feeding to the printer. It receives the raw glaze and it adjusts their rheological conditions and make them suitable for the printer. For doing this, a viscometer was designed, able to tune in real-time the density and viscosity of the as-received glazes in the production lines. In addition, a vision control system to perform in real time the quality inspection of the yield tiles was also studied and implemented. Both additional instruments can be controlled in place and on-remote and are integrated with the main printer following the protocols of Industry 4.0 most used in ceramic tile manufacturing lines (Modbus TCP).

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The Glazetile project has brought to the community of ceramic tile manufacturers a digital revolution for the glazing phase. The state-of-art process, i.e. spraying, which is a highly polluting and toxic process for the workers’ health, extremely energy and water consuming generating a huge amount of glaze waste, is being currently replaced by TecnoItalia digital technology. At the beginning of the project, two development options were envisaged for the glaze deposition: (i) one with the use of solenoid valves and (ii) the other by working with an electromechanical distributor. Thanks to the intensive work of design and in-field verification performed by TI, the second solution was proved to be the most efficient in terms of quality of deposition and has produced quality results not found with other printers on the market.
TecnoItalia has achieved excellent results for the deposition of glaze: the quality of this deposition has been recognized by some beta-test customers as unique on the market, achieving the KPIs hypothesized in the project. We are commissioning specific measurements to the University of Modena for the assessment of these parameters by an LCA study, as mentioned in the Grant agreement, including the analysis of the socio-economic impact and the wider societal implications of the project so far. Based on the results of the LCA study, Tecno Italia aims to propose to The Italian ceramic tile and refractory materials manufacturers’ association Assopiastrelle to work together to bring new greener standards more respectful and protective for workers in the ceramic glazing sector.

DigiGlaze 4.0 bar

DigiGlaze 4.0 printer