① on coloring. Is the glass material adding cobalt (Co) and manganese (Mn), nickel (Ni), iron (Fe), copper (Cu), and other compounds, the transition elements in ionic state exists in the glass, because of their valence electrons transition between different energy levels (ground state and excited state), cause the selection of visible light absorption and coloring, such as cobalt blue color such as nickel, manganese violet, green glass.
② compound colloid particle coloring. Is to contain zinc (ZnO) in the glass to add sulfur or selenium compounds (such as CdS, CdSe, etc.), in the glass to form CdO, ZnS, ZnSe, etc., and then under the annealing temperature under two heat treatment, forming CdS, CdSe and grow into very large colloidal particles, due to light scattering and make the glass color, such as selenium red, cadmium yellow and other color glass.
③ Coloring of metal colloid particles. Is the glass raw material add easily decomposed into the state of the metal oxide (such as gold, silver, copper oxide), start with ion dissolved in a glass, the heat treatment into atomic state and gathered together and grow up into colloid particles, caused by light scattering on the absorption of visible light and color, such as the red, red copper, silver yellow color glass, etc.
④ Semiconductor coloring. It is to add CdS, CdSe, CdTe and other colorants to the glass material. There is no absorption peak in the visible light region and a continuous absorption region. The transmittance region and absorption region are a dividing line with a very steep slope. Different from the above coloring mechanisms, its color changes with the ratio of CdS/CdSe, for example, when CdS is near orange, WHEN CdSe is red, and when CdTe is black, that is, they move to the long wave direction in the order of O2-, S2-, Se2-, and Te2-. According to the semiconductor energy band theory, the electrophilic potential of these anions decreases in turn, and light with lower energy (near visible light) can be used to excite their valence electrons to the conduction band (excited state), so that the short-wave cut into the visible light region is more limited, resulting in glass coloring.
Post time: Dec-21-2021