Formulation of High Reflection Engobe and Their Industrial Uses for Earthenware Wall Tile

Main Article Content

phatcha Supalukmeta
Heiko Hessenkemper
worapong Thiemsorn


The aim of this paper is to reveal the correlations between the white/high reflection engobe (WRE) composition and their properties for earthenware wall tile industry. The engobes were formulated using (wt%) porcelain clay (PC) 72-80, recycled cullet (RC) 9-10, borax 9-10 and TiO2 0-9. The mixtures were wet ground for 30 min in a pot mill and their specific gravity was controlled at 1.6 g/cm3. The engobe slips were spray coated on earthenware wall tiles different thicknesses at 160-250 gif.latex?\mum. The engobed tiles were single-fired at 950-1100oC in a gas furnace for 15 min. The coefficient of thermal expansion (CTE) was determined by dilatometer. The adhesion ability was investigated by tape-peel method. The whiteness and reflection values were determined by colorimeter and  spectrophotometer, respectively. The phase composition and microstructure were evaluated by x-ray diffractometer and scanning electron microscope, respectively. The results showed the WRE composing microline, anatase, albite, anorthite, quartz and corundum had the CTE values nearby the wall tile. The whiteness and reflectance reached to the highest values at 4.76 wt%TiO2 and layer thickness at 250 gif.latex?\mum. At high temperatures, the whiteness and reflection slightly decreased due to the formations of mullite and rutile. The optimization of WRE composed (in wt%) of PC 76.19, RC 9.52, borax 9.52 and TiO2 4.76% representing whiteness 95.51%, reflectance up to 85% by controlling the thickness at 250 μm and temperature at 1000oC.


Download data is not yet available.

Article Details

Research Article


L. Esposito, P. Generall, A. Tucci, and S. Nuzzielo, “Hardness of glazed ceramic tiles: comparison between mohs hardness and vicker indentation method,” Ceram. Acta., vol. 5(4-5), pp. 13-21, 1993.

M. Romero, J. M. Rincon, and A. Acosta, “Crystallization of zirconium-based glaze for ceramic tile coating,” J. Eur. Ceram. Soc., vol. 23, pp. 1629-1635, 2003.

C. Ferrari, A. Libbra, A. Muscio, and C. Siligardi, “Design of ceramic tile with high solar reflectance through the development of a functional engobe,” Ceram. Inter., vol. 39, pp. 9583-9590, 2013.

R. Levinson, P. Berdahl, H. Akbari, W. Miller, I. Joedicke, J. Reilly, Y. Suzuki, and M. Vondram, “Methods of creating solarreflective nonwhite surfaces and their application to residential roofing materials,” Solar Ener. Mater. Solar Cells, vol. 91(4), pp. 304-314, 2007.

A. Synnefa, M. Santamouris, and K. Apostolakis, “On the development, optical properties and thermal performance of cool colored coatings for the urban environment,” Solar Ener., vol. 81(4), pp. 488-497, 2007.

S. Kültür and N. Türkerí, “Assessment of long term solar reflectance performance of roof coverings measured in laboratory and in filed,” Build. Environ., vol. 48, pp. 164-172, 2012.

R. Levinson, P. Berdahl, and H. Akbari, “Solar spectral optical properties of pigments- Part II: survey of common colorants,” Solar Ener. Mater. Solar Cells, vol. 89(4), pp. 351-389, 2005.

T. Thongkamluang, T. P. Limsuwan, and P. Rakkwamsuk, “Preparation and application of high near-infrared reflective green pigment for ceramic tile roofs,” Inter. J. Applied Ceram. Technol., vol. 8(6), pp. 1451-1458, 2011.

G. A. Davidson, “A modified tape-peel technique for preparing permanent qualitative microfossil slides,” J. Paleolimnol., vol. 1, pp. 229-234, 1988.

“Borax data sheet,” Riotinto Minerals, US.

G. R. Santos, M. C. Pereira, M. O. Dionysio, S. D. Souza, and M. R. Morelli, “Whiteness process of tile ceramics: using a synthetic flow as a modifier agent of color firing,” Hyper. Interact, vol. 224, pp. 137-142, 2014.

M. Romero, J M. Rincón, and A. Costa, “Effect of iron oxide on the crystallization of a diopside glass-ceramic glaze,” J. Euro. Ceram. Soc., vol. 22, pp. 883-890, 2002.

C. Li, G. W. Kaatawar, and P. Yand, “Effects of surface roughness on light scattering by small particles,” J. Quanti. Spcetro., vol. 89, pp. 123-131, 2004

H. Bodur, “Development of engobe compositions for local roof tiles,” M. Sc. Thesis, Engineering and Sciences of Izmir Institute of Technology, Izmir, Turkey, June 2010.

S. B. Felisbino, K. W. Milanez, H. G. Riella, and A. M. Bernardin, “Influence of glaze particle size distribution on surface tension and gloss,” in Proc. Qualicer, 2004, p. 201.

R. H. French, H. Müllejans, and D. J. Jones, “Optical properties of aluminum oxide: Determined from vacuum ultraviolet and electron energy-loss spectroscopies,” J. Amer. Ceram. Soc., vol. 81(10), pp. 2549-2557, 1998.

I. Johari, S. Said, B. Hisham, A. Bakar, and Z. A. Ahmad, “Effect of the change of firing temperature on microstructure and physical properties of clay bricks from Beruas (Malaysia),” Sci. Sinter., vol. 42, pp. 245-254, 2010.

S. Teixeira and A. M. Bernardin, “Development of TiO2 white glazes for ceramic tiles,” Dyes and Pigments, vol. 80, pp. 292-296, 2009.