ARZ Range, your optimum solution. for zircon substitution. TILE

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1 ARZ Range, your optimum solution for zircon substitution. TILE

2 ALTEO CAN OFFER THE COMPLETE TECHNICAL SOLUTION TO CERAMIC MANUFACTURERS: AN INNOVATIVE OPTIMISED ALUMINA TO REPLACE ZIRCON AND A FULL TECHNICAL SUPPORT.

3 HOW ABOUT Over the past 3 years, constraints on the availability of zircon and the volatility of prices have put a lot of pressure on manufacturers that use zircon in their formulations. In response, Alteo launched its programme to develop the ARZ specialty alumina range to replace zircon in tile bodies, engobes and glaze formulations. With a long standing and extensive experience in the ceramics market, and tiles in particular, this development has combined the expertise of Alteo in specialty aluminas together with external partners, expert in both ceramic research and, of course, in the manufacturing of ceramic tiles. Today the ceramics group in Alteo s research and development team is fully focussed on optimizing and enhancing the ARZ range. At the same time, it is making full use of the extensive facilities of the application laboratory to identify new formulations. The objective for Alteo is to offer the complete technical solution to ceramic manufacturers: the optimum product to replace zircon together with full technical support.

4 ARZ RANGE FOR ZIRCON REPLACEMENT ARZ RANGE USED AS COMPONENT IN THE COMPOSITION: SAVES ZIRCON GIVES HIGH LEVEL OF WHITENESS AND OPACITY ARZ ARZ is a low calcined alumina with an intermediary specific surface ARZ is used in engobe and glazes to replace zircon AFRZ AFRZ is a ground low calcined alumina with very controlled and stable particle size distribution AFRZ is used in the tile body

5 ALTEO S R&D LABORATORY STUDIES A key part of the Alteo development approach is to continually improve the understanding of how products work in customer applications. For the ARZ zircon replacement project, as with many other application projects in Alteo s R&D portfolio, there is a three part approach: studies at the Gardanne R&D facility; studies with recognised independent research organisations and universities; and tests with customers and prospects. Further details about the Alteo application laboratory can be found later in this brochure. The aim of the work was to introduce alumina in a floor tile body and in an engobe composition to evaluate the behaviour of the alumina as an opacifier and as a whitening agent. This work, which shows total replacement of zircon by ARZ or AFRZ in formulations, illustrates how to reduce recipe cost and keep total control of raw material introduced in the formulation.

6 REPLACEMENT OF ZIRCON BY ALUMINA AS AN OPACIFIER IN A TILES BODY COMPOSITION FOR PORCELAIN STONEWARE The alumina tested was the following: AFRZ is a ground low calcined aluminium oxide Al 2 O 3 with an intermediate specific surface. In order to perform this stage a porcelain stoneware tile composition with 5% zircon was used as the standard composition and new compositions with 7.5 % alumina replacement were prepared for comparison. Workprogram Analyses results from pressed samples: In order to determine the firing behaviour of the bodies, tests were performed using pressed samples of the tile body compositions. Tests were conducted with each composition to determine: Pressing at constant pressure Vitrification diagram Chromatic coordinates AFRZ was added after the milling as a whitening additive. All the compositions have the same oversize at 40µm after grinding: 1.2%.

7 Porcelain stoneware tile compositions & results obtained Standard COMPOSITION % AFRZ Figure 1. Evolution of bulk density with temperature. Compositions with Zircon or AFRZ 23,0 White Clay 22,4 66,0 Feldspar Na 64,3 6,0 Quartz 5,8 5,0 Zircon 0,0 0,0 AFRZ 7,5 RESULTS OBTAINED 1,2 Oversize 40µm (%) 1,2 5,0 Moisture content (%) 5,0 350,0 Pressure (kg/cm²) 350,0 2,013 Dry bulk density (g/cm3) 1,975 Optimal firing temperature 1200C 7,6% Linear shrinkage (%) 7,6% 0,05% Water absorption (%) 0,03% 2.47 Apparent density (g/cm3) 2,48 CIE Colour after firing 84,0 L* 84,0 1,62 a* 1,60 10,08 b* 9,43 Bulk density (g/cm 3 ) % 4.5% Bulk density 4.0% % 3.0% 2.5% % % 1.0% 0.5% 2.38 Water absorbtion % % -0.5% Temperature ( C) Zircon standard composition AFRZ composition Evolution of bulk density with temperature. Water absorption (%) Note: AFRZ has been added after the milling of the composition. Conclusion 7.5 % AFRZ allows complete replacement of zircon and gives the same level of whiteness as zircon in the tiles body composition. The use of pure alumina in the recipe gives tiles producers complete control of all the raw materials used in the formula.

8 REPLACEMENT OF ZIRCON BY ALUMINA AS AN OPACIFIER IN ENGOBES FOR WALL TILES AND FLOOR TILES The alumina sample tested was: ARZ - a low calcined aluminium oxide Al 2 O 3 with an intermediate specific surface. In order to perform this stage two engobe compositions were used as standard compositions : for wall tiles with 3% of zircon for floor tiles with 13% of zircon New compositions with reformulations were prepared for comparison. Workprogram Analyses results from pressed samples In order to determine the firing behaviour of the engobes, tests were performed using pressed samples of engobe. Tests were conducted with each composition to determine: Linear shrinkage Vitrification phase diagram Chromatic coordinates The ARZ alumina was ground with the other raw materials. Analyses results from applied samples: In order to evaluate more easily the whiteness behaviour of the engobes, suspensions were applied to redware wall tile biscuits and dark floor stoneware tiles. Tests were conducted with each composition to determine: Chromatic coordinates Permeability (with half of the tile deposited in water) After grinding all the compositions had the same oversize at 40µm.

9 Engobes for Wall Tile compositions and results obtained Standard COMPOSITION % ARZ 37,2 Opaque Frit 38,3 23,5 Quartz 25,0 16,4 Kaolin 17,9 10,7 Clay 6,7 9,2 AC44 Calcined Alumina 9,2 3,0 Zircon 0,0 0,0 ARZ 3,0 Optimal firing temperature 1115C 0,7 Oversize 40µm (%) 0,7 5,0 Moisture content (%) 5,0 250,0 Pressure (kg/cm²) 250,0 2,101 Dry bulk density (g/cm 3 ) 2,068 Pressed samples 4,3% Linear shrinkage (%) 4,3% 0,05% Water absorption (%) 0,04% 2,420 Apparent density (g/cm3) 2,398 91,93 L* 92,20-0,33 a* -0,31 4,95 b* 5,44 Engobes on tiles 90,69 L* 90,76 0,68 a* 0,76 4,78 b* 4,74 0,986 Opacity Index - OP=(L*Tile/L*engobe) 0,979 0,3 Permeability E 0,4

10 Engobes for Floor Tile compositions and results obtained Standard COMPOSITION % ARZ 25,5 Frit 30,5 8,0 Na Feldspar 6,5 12,0 Quartz 10,5 34,0 Clay 32,0 6,5 AC44 Calcined Alumina 6,5 14,0 Zircon 3,0 0,0 ARZ 11,0 Optimal firing temperature 1200C 1,2 Oversize 40µm (%) 1,1 5,0 Moisture content (%) 5,0 250,0 Pressure (kg/cm²) 250,0 2,27 Dry bulk density (g/cm 3 ) 2,11 Pressed samples 2,59% Linear shrinkage (%) 2,55% 0,02% Water absorption (%) 0,05% 2,434 Apparent density (g/cm3) 2,413 86,90 L* 88,45 0,99 a* 0,65 8,56 b* 8,42 Engobes on tiles 87,79 L* 89,84 1,17 a* 0,64 7,77 b* 7,93 1,010 Opacity Index - OP=(L*Tile/L*engobe) 1,016 0,4 Permeability E 0,5 These tests enabled comparison of the colour of the material, but not its opacity. The L* coordinate of the engobed tiles is related to the opacity of the engobe. If the engobe was totally opaque, for the same temperature the L* coordinate of the engobed tiles would be the same as the L* coordinate of the pressed samples.

11 Conclusion Reformulation of the ARZ based composition by introducing powerful fluxing raw materials: Counteracts refractoriness caused by alumina Allows complete replacement of zircon by alumina ARZ can be used as an opacifier and a whitening additive in an engobe composition.

12 LOW CALCINED ALUMINA ARZ Low calcined aluminium oxide, Al 2 O 3, with an intermediary specific surface area and a standard soda content. This grade is used to replace, fully or partially, the zircon in engobe and glazes in the tiles industry. Characteristics Unit ARZ Surface Area BET m²/g 8 PSD Laser D50 µm 45 <125 µm % 97 Chemical composition Al 2 O 3 % 99.4 Na 2 O total ppm 3200 CaO ppm 150 SiO 2 ppm 165 Fe 2 O 3 ppm 120

13 Characteristics Unit AFRZ Surface Area BET m²/g 9.8 PSD Laser D50 µm 3.2 D90 µm 20.6 <125 µm % 100 Chemical composition Al 2 O 3 % 99.4 Na 2 O total ppm 3200 CaO ppm 150 SiO 2 ppm 165 Fe 2 O 3 ppm 120 GROUND LOW CALCINED ALUMINA AFRZ Ground low calcined aluminium oxide, Al 2 O 3, with an intermediary specific surface area and a standard soda content. This product is ball milled. This product is used in the tiles industry in body.

14 THE ALTEO R&D DEPARTMENT THE CERAMICS APPLICATION LABORATORY CAPABILITIES AND KNOW-HOW Impact of alumina characteristics on your processes e.g.: slurry recipies, viscosity, grinding, shaping, sintering Impact of alumina characteristics on ceramic properties e.g.: density, porosity, permeability, shrinkage, color, hardness, mechanical strength Development of our alumina range adapted to the market needs Research of new applications for alumina Patent filing to protect our innovations Customized adjustment of your recipes to help integrate our alumina in your ceramic Studies undertaken in total confidentiality

15 KNOWLEDGE OF OUR PRODUCTS we can analyze in detail our aluminas STANDARD CONTROL IN THE ANALYSIS LABORATORY Chemistry Particle size distribution Specific surface area Crystallography SPECIFIC CONTROL IN THE APPLICATION LABORATORY The shape of grains Microscopy KNOWLEDGE OF THE APPLICATIONS OF OUR PRODUCTS we can work and simulate all the steps of your process Mixing with minerals (clay, kaolin, feldspars ) "Thanks to the best equipment Slurry, granules, paste preparation Engobes and glazes Shaping Sintering Mills, rheometer, zetameter Kneader Press Slip casting Piston extruder Kilns, debinding kiln and to ceramic specialists" APPLICATION OF OUR PRODUCTS we can work on the final ceramic properties Density, porosity Sintering shrinkage Microstructure (SEM+EDX) Colour and whiteness (L*a*b*) Gloss Water absorption Stain resistance Mechanical resistance (bending and compression) Wear resistance Hardness Thermal expansion For the ARZ zircon substitution programme, technical-economic studies involving the introduction of ARZ and AFRZ in a formulation can be carried out. With complete confidentiality, a client s raw materials can be used in our laboratory, using the latest technical equipment and procedures. This way customised studies of formulations or technical service are ensured.

16 ALTEO AT A GLANCE World s largest supplier of specialty aluminas with tonnes of alumina based products (hydrate, calcined, tabular and fused aluminas) Headquartered in Gardanne (France) with 4 production facilities in Europe Global sales network Development centre in Europe Leading positions in Ceramics (technical and standard), Refractory, Abrasives, Specialty Glass, Chemicals, Feedstock ALTEO - Route de Biver B.P Gardanne Cedex France