AbstractIn general, the main compositions of porcelain and bone china composed of 54-65%wt silica (SiO2), 23-34% wt alumina (Al2O3) and 0.2-0.7%wt calcium oxide (CaO) suitable for preparation high quality ceramic products such as soft-hard porcelain products for teeth and bones, bioceramics, IC substrate and magneto-optoelectroceramics. The quality of ceramic hand mold is depended on raw material and its properties (pH, ionic strength, solid-liquid surface tension, particle size distribution, specific surface area, porosity, density, microstructure, weight ratio between solid and water, drying time, and firing temperatures). The suitable firing conditions for porcelain and bone china hand-mold preparation were firing at 1270°C for 10 h which resulted in superior working molds for making latex films from natural and synthetic rubber. The obtained fired porcelain hand molds at 1270°C for 10 h provided good chemical durability (10%NaOH, 5%HCl and 10%wtNaCl), low thermal expansion coefficient (5.8570 × 10−6 (°C−1)), good compressive (179.40 MPa) and good flexural strength (86 MPa). While thermal expansion coefficient, compressive and flexural strength of obtained fired bone china hand molds are equal to 6.9230 × 10−6 (°C−1), 128.40 and 73.70 MPa, respectively, good acid-base-salt resistance, a smooth mold surface, and easy hand mold fabrication. Both obtained porcelain and bone china hand molds are a low production cost, making them suitable for natural and synthetic rubber latex glove formation.
Self-Reported Latex Glove Hypersensitivity Among Dental Personnel In Aimst Dental Institute
