| 摘要 |
The present invention is primarily concerned with the production of transparent glass-ceramic articles especially suitable for use as cooking utensils nucleated with up to 6% TiO2 and containing up to 0.25% Fe2O3 and, perhaps, up to 0.1% MnO2, which exhibits a light brown tint that the human eye perceives essentially constant when the dominant wavelength is held between 577-581 nm, purity between 8-15%, and the transmission factor between about 65-80. The desired tint is obtained by including 0.0025-0.02% CoO+Cr2O3, consisting of 0.001-0.01% CoO and 0.001-0.01% Cr2O3, in the base composition of the glass-ceramic. An opaque glass-ceramic article exhibiting a light, warm creamy color perceived by the human eye as essentially constant when the dominant wavelength is held between 570-585 nm, the reflectance factor is in excess of 64, and the purity factor is no greater than 8% can be produced from like base compositions which are crystallized in situ at higher temperatures.
|
