During the Spring Festival of dog year, the Chengdu Museum of Sichuan province held the "treasure exhibition of Afghanistan". It took only four days to attract more than fifty thousand people to visit the site. The exhibition of cultural exchanges between the East and the west, The Belt and Road can promote development. Among the exhibits are a large number of glassware from the archaeological sites in Afghanistan. As a typical product of Rome Empire, the patterns on these glassware are very beautiful, which fully demonstrates the outstanding craft of glass manufacture at that time. In addition, imitation jade, jade, coral and other bottles, bowls, nose and other glassware, not only vivid, with a unique style and flavor, the surface of the pattern is often a bright eye. Then, how did the patterns on the surface of these glassware be made? Painted glass in the treasure exhibition in Afghanistan. (network diagram) glass is stable in nature. It is not afraid of hydrochloric acid, sulfuric acid and aqua regia erosion. It also can withstand strong alkali corrosion. At the same time, the glass itself is very hard, and it usually needs to be cut by diamond or other alloy. Obviously, it is not easy to cut patterns on glass. "One thing drop one thing". When the glass is touched with hydrofluoric acid, it will be corroded. Because fluorine is a lively element, it can react with almost all elements. Fluorine and hydrogen combine to form hydrogen fluoride, and hydrogen fluoride dissolves in water to become hydrofluoric acid. Hydrofluoric acid (HF) is an oxygen free acid formed by halogen elements. It has very strong corrosiveness and chemical reaction occurs when it meets glass. How does hydrofluoric acid react with glassware? Originally, glassware was made mostly of soda lime silicate glass, and its main component was silica. Silica is a colorless, transparent or white powder. It has a high melting point, hard to melt, insoluble in water, and natural silica, commonly known as silica, is one of the components of the rock. Silicon dioxide meets hydrofluoric acid, which produces volatile four silicon fluoride gas and water.
So the glass is corroded to wool glass. The chemical formula of the two reactions is: SiO2+4HF==SiF4+2H2O surface etched beautiful home glass. (from visual China) hydrofluoric acid is the "craftsman" of etching glass. With this characteristic, all kinds of beautiful patterns can be carved on glass handicrafts. The concrete method is to dip the glassware in the melted paraffin first, then cut the wax into the pattern with a knife, then apply hydrofluoric acid, or put it into the hydrogen fluoride gas to corrode. When the residual hydrofluoric acid is removed and the wax is scraped away, beautiful patterns are left on the glassware. This method is also used to calibrate or add words to the surface of glass chemical instruments such as measuring cylinders and burette. Laboratory glassware. (network diagram) in industry, acid polishing is widely used to make different effects on the surface of glass. Acid polishing, that is, before applying hydrofluoric acid, puts glassware in different acids to make it better. As a digression, it is because hydrofluoric acid corrodes glass, so do not store hydrofluoric acid in glass containers.