Ceramic glaze

Abstract: The management of electrical and electronic equipment waste (WEEE) is a significant problem of industrialized countries, in the last decades it has been noticed an appreciable increase of this residue, consisting of about 80% of television sets and computers containing end of life (EOL) cathode ray tubes (CRT). Specific technologies permit to dismantle the kinescope, obtaining different glasses with high quality level and specific chemical compositions. The presence of dangerous elements makes critical the re-use in many fields of application. The present work proposes the feasibility of CRT glass recycling in ceramic field using it into a base glaze formulation as substitute of “ceramic frits”. The study was conducted in two phases, laboratory scale in order to study the suitable glaze formulation and semi-industrial scale with the technological support of an Italian ceramic glaze producer. The glazes obtained have aesthetic and mechanical properties extremely similar to the standard ones.

Abstract: A set of laboratory experiments has been developed to determine the nature and importance of the interaction between clay bodies and lead glazes during firing following different thermal paths (firing time and temperature, cooling rates) and using different glaze compositions and different bodies (illitic, kaolinitic, and calcareous clays). It is shown that the interaction consists of a digestion/diffusion process. This process involves (i) decomposition of the phases forming the clay body (digestion), (ii) chemical diffusion of elements between clay body and glaze, and (iii) formation of a layer (interface between clay and glaze) of small K-Pb feldspar crystallites.

Abstract: Objective To evaluate and compare color stability and gloss retention of ceramic stains and glaze under simulated toothbrushing using dentifrices with different relative dentin abrasion (RDA). Materials and methods Feldspathic porcelain, lithium disilicate, 3 mol% yttria partially stabilized zirconia, and 5 mol% yttria partially stabilized zirconia were evaluated. Ceramics were externally stained, glazed and mounted in the toothbrush simulator. A toothbrush with 300 g force was applied. Regular toothpaste (72 RDA) and charcoal toothpaste (RDA Results ΔE00 was significantly different at 50 k cycles and with zirconia ceramics (P .0001). Loss of gloss was observed at 5 k and 30 k (charcoal and regular toothpaste respectively) regardless type of ceramic (P > .0001). Conclusion Glass-phase ceramics retain stains longer than zirconia ceramics. Charcoal toothpaste affect color and gloss stability. Ceramic glaze maybe lost within the first 6 months in patients' mouth. Clinical significance Long-term color and gloss stability of externally stained and glazed ceramics maybe a clinical concern. Charcoal toothpastes enhance loss of color and gloss of ceramic restorations.