Glass-ceramics are ceramic materials produced through controlled crystallisation (nucleation and crystal growth) of a parent glass. The great variety of compositions and the possibility of developing special microstructures with specific technological properties have allowed glass-ceramic materials to be used in a wide range of applications. One field for which glass-ceramics have been developed over the past two decades is that of glazes for ceramic tiles. Ceramic tiles are the most common building material for floor and wall coverings in Mediterranean countries. Glazed tiles are produced from frits (glasses quenched in water) applied on the surface of green tiles and subjected to a firing process. In the 1990s, there was growing interest in the development of frits that are able to crystallise on firing because of the need for improvement in the mechanical and chemical properties of glazed tiles. This review offers an extensive evaluation of the research carried out on glass-ceramic glazes used for covering and pavement ceramic tile is accomplished. The main crystalline phases (silicates and oxides) developed in glass-ceramic glazes have been considered. In addition, a section focused on glazes with specific functionality (photocatalytic, antibacterial and antifungal activity, or aesthetic superficial effects) is also included

The authors want to thank Mr. R. Rincón for the kind assignment of the Ishtar gate photograph shown in Figure 4 and to Ms. D. Fernández and Mr. E. Fernández (Department of Library and Publications, IETcc-CSIC) for their assistance in compiling the references necessary for the completion of this review. R. Casasola is grateful to the Spanish National Research Council (CSIC) for her contract through the JAE Program (JAE Pre_08_00456). Financial support through the project MAT2006-05977 (Education and Science Spanish Ministry) is also recognised.

Peer reviewed