Glassware is a vessel made of glass. Glass art has maintained a history of development for thousands of years in China. During the Wanli period of the Ming Dynasty, the production of materials in Shandong Boshan was very prosperous. It was introduced to Beijing in the late Ming and early Qing dynasties. During the Kangxi, Yongzheng and Qianlong periods in the early Qing Dynasty, the production of glass was once revived. In the thirty-five years of Qing Emperor Kangxi, Beijing appeared The scale of the "glazed factory", the production of the material enjoyed by the palace. During this period, the variety of glassware was varied, and the shape and decoration were also changed. Among them, bottles, bowls, snuff bottles, birds and beasts made of jade, jade, agate, coral, etc., are vivid in color and have a unique style and charm.
Glassware is made of soda lime silicate glass. Colorless and transparent vessels, the iron content in the glass is generally less than 0.02%. A coloring agent is added to the glass raw material to obtain a colored glass; and an opacifying agent is added to obtain an opaque glass (see glass manufacturing). The high-grade artware such as goblets, perfume bottles and fruit bowls used in the manufacture of honing cars are mostly made of potassium lead silicate glass, also known as lead crystal glass. This glass contains PbO, has a high refractive index and dispersion, and is particularly bright when polished, with a high specific gravity and a crisp sound when struck. More than 30% of PbO is full lead crystal glass, including PbO 24 to 30% is medium lead crystal glass, and PbO 18% or less is low lead crystal glass. There is also a bismuth crystal containing BaO. Products such as cooking utensils such as coffee pots are made of heat-resistant borosilicate glass, which has a low coefficient of thermal expansion and is resistant to rapid temperature change. Glass-ceramics have better heat resistance and temperature-resistant variability, and are mechanically strong, making them suitable for the manufacture of simmered vessels and utensils that are often washed in hotels.
The powder and clinker combined with the glass component are melted into the kiln or the pool kiln (see glass melting furnace), and after melting, they are clarified into a uniform bubble-free, stone-free, streak-free glass liquid, and then cooled to adapt to the corresponding The viscosity range required for the molding method is subjected to various molding operations.
Blown
There are two ways of manual and mechanical blow molding. In the manual molding, the hand-held blow pipe is picked up from the inside of the crucible or the kiln take-up port, and blown into a shape in a metal mold or a wood mold. The smooth circular product is subjected to a rotary blowing method; the surface has a convex or concave pattern or a shape in which the shape is not circular, and the static blowing method is used. First, pick the colorless material and blow it into small bubbles, and then use the small bubble to pick the color material or the emulsified material to blow into a shape called a nesting. The color fusible granules are immersed in the turbid nesting material, and the natural color flow of each color can be blown into a natural ware vessel; the squeegee material is smeared on the color material, and can be blown into a drawing vessel. Mechanical forming is used to blow large quantities of products. After the blowing machine receives the material, the automatic iron mold is blown into a shape, and after the mold is removed, the cap is removed to form a vessel. Press-blow molding can also be used to first punch the material into small bubbles (formation) and then continue to blow into a shape. It is more efficient and of better quality than a blower.
Pressing
When artificially forming, the artificial picking material is cut into the iron mold, the punch is driven, the shape is pressed into a shape, and the mold is fixed after being fixed. Mechanical molding automation production, large batch size and high efficiency. Press forming is suitable for small-bottomed products such as cups, plates, and ashtrays that can be withdrawn from the punch.