Colorants that change the color of glass are common

The substance that makes the glass coloring is called the colorant.

The role is to make the glass selectively absorb light, showing a certain color.

Colorants are divided into three categories: ionic coloring, colloidal coloring, and sulfur selenide coloring, of which the main one is ion coloring.

The coloration of common ions (chromium, titanium, copper) is a transition metal element and a rare earth metal element, commonly including cobalt, copper, cerium, titanium, chromium, manganese, nickel, selenium.

Chromium ions: yellow-green under oxidation atmosphere, emerald green under reducing conditions; titanium ions: yellow; copper ions: blue-green.

Iron ions: refers to the different coloring due to the existence of the variable price pattern of iron. Fe3+ the maximum transmittance in 560 ~ 600NM, glass yellow, and divalent iron FE2 + maximum transmittance in 470 ~ 480NM, glass is blue-green, ferrous than the coloring capacity of iron oxide about 10 times larger, due to the different atmosphere, iron in different valence states, its coloring ability will be greatly different.

Sulfur - carbon coloring: is the coexistence of sulfides and trivalent iron ions produced, carbon only plays the role of reducing agent, sulfur - carbon coloring glass color brown and red, color like amber, widely used in bottle glass and utensil glass.

Chemical decolorization: It is with the help of the oxidation of decolorizing agents that make the low-cost iron oxide (FeO) with strong coloring ability become a trivalent iron oxide (Fe2O3) with weak coloring ability, and at the same time, the glass is eliminated by the yellow color contaminated by organic matter, so that the light transmittance of the glass is increased. Commonly used chemical decolorizing agents are sodium nitrate, potassium nitrate, antimony trioxide, cerium oxide, manganese oxide and the like.