About the concept of glass
Glass, was also called Liuli in ancient China. The Japanese Chinese characters are represented by glass. It is a relatively transparent solid substance that forms a continuous network structure when melted. During cooling, the viscosity gradually increases and hardens without crystallization. The composition of ordinary glass chemical oxide is Na2O•CaO•6SiO2, and the main component is silicon dioxide.
Glass is chemically inert in the daily environment and does not interact with organisms, so it is very versatile. Glass is generally insoluble in acid (exception: hydrofluoric acid reacts with glass to form SiF4, which leads to glass corrosion), but it is soluble in strong alkalis, such as cesium hydroxide. The manufacturing process is to melt various well-proportioned raw materials and quickly cool them down. Each molecule does not have enough time to form crystals to form glass. Glass is a solid at room temperature. It is a fragile thing with a Mohs hardness of 6.5.
The history of glass
Glass was originally obtained from the solidification of acid rocks ejected from volcanoes. Before 3700 BC, the ancient Egyptians were able to make glass ornaments and simple glassware. At that time there was only colored glass. Before 1000 BC, China manufactured colorless glass.
In the 12th century AD, commercial glass for exchange appeared and began to become an industrial material. In the 18th century, to meet the needs of developing telescopes, optical glass was produced. In 1873, Belgium took the lead in manufacturing flat glass. In 1906, the United States developed a flat glass lead-up machine. In 1959, the British Pilkington Glass Company announced to the world that the float forming process for flat glass was successfully developed, which was a revolution in the original grooved forming process. Since then, with the industrialization and large-scale production of glass, glass of various uses and various properties has come out one after another. In modern times, glass has become one of the important materials in daily life, production, and science and technology.
Post time: Feb-21-2021