History of glass industry

From the stained-glass windows of medieval churches to the famous mirrors in Renaissance Venecia, glass panels have given us the protection of the environment and at the same time reflected the beauty of nature, giving people year-round comfort, reducing energy costs, improving safety and replacing walls with bricks and mortar with a panorama of natural light and beauty .

The history of glass

The first glass was a mineral of borax, created naturally in volcanic explosions. Glass was made about 1500 BC in Egypt and Mesopotamia. These ancient cultures made glass objects with rudimentary casting methods. The first glassmakers shaped glass by covering liquid glass around a core of sand or clay, then removing the material as a core. Finally, the cooled glass is cut and polished.

In the next millennium, glass fabrication was carried out more widely in the ancient world and there were some improvements in the method of making basic glass, such as cutting work. Glass workers have learned how to add some ingredients to glass to increase durability, make glass clearer or create special colors. However, the making of glass is still very difficult and glass is mainly used in the royal family for religious ceremonies.

The glass industry witnessed the first revolution about 300 BC, when Siri glass craftsmen invented a bellows, helping to create a multitude of products that differ in shape and thickness. Immediately after the invention of the bellows was the appearance of a half-mold, which allowed glassmakers to create a series of identical glass objects. These two inventions first made glass products affordable to ordinary people.

In the first century AD the Romans revolutionized glass making by using a variety of methods such as blowing glass, blowing into molds and molding with mass production of products. Different shaped glass used in decoration. Window glass, manufactured by pouring and stretching molten glass on a steel table, changed the look of the architecture. The Roman Empire also produced sheet glass by blowing large balls or cylinders, then separated and flattened. They also started making mirrors by coating silver on glass plates. This Roman creation was soon spread throughout Europe.

With the fall of the Roman Empire, many techniques of glass craft were lost. In Western Europe, glass became the product for the rich and the glass plate used to make the windows of medieval churches. However, Byzantine glass industry continues to create new innovations. Around 650 AD, Siri glass craftsmen developed a revolutionary new glass technology to produce "crown" glasses (org. " Crown "). This type of glass is made by creating a hole in a molten glass ball, then rotating a soft glass block to make a thin, round glass with a special " bulls-eye" at center. Because this type of glass is not so expensive, it is used as a window glass until the end of the 19th century.

Venecians have imported glass products from Byzantine and started their prosperous glass industry since the 13th century. To protect "trade secrets" , glass furnaces were transferred to Murano Island, where the revival of the Italian glass industry continued for several centuries. The Venecians have perfected the technology of producing glass plates with the colorless glass casting method on the steel table, then polishing the glass plate until it is no longer wavy. Venecians also developed mercury-coated methods to make famous mirrors across Europe. While a lot of people died of mercury poisoning, the mirror was so highly profitable, that the bishops gave death sentences to those who revealed technology secrets. Despite these efforts, Venecia's glass making experiences spread throughout Europe. Soon, French glass craftsmen improved Italian technology with large tables to make larger-sized glass panels, making incubators to cool the glass for a few days. Glass craft was also completed in Germany, North Bohemia and England, where George Ravenscoft invented lead glass in the 1670s . Around the same time, sheet glass was also produced in France by a cylindrical method. To improve Roman technology, French workers blow long glass pillars, separate it and flatten it with wooden blocks to create a rectangle.

With the advent of British plate glass company in 1773, England has become the center of high quality window glass of the world. This is the milestone for the first time in the history of the glass industry, glass windows have become affordable for most homeowners.

He was the first country to find and set up his glass manufacturing centers in the colonies of the Americas. They fear competition from domestic producers and outlaw glass ovens in the Americas. After the American revolution, glass making technology spilled over from Europe, forming a vivacious glass industry in the United States. The first creation of American manufacturers was the invention of the press, patented in 1825. During the pressing process, the liquid glass was poured into the mold and pressed to create the desired shape. thanks to piston.

The Industrial Revolution brought a series of innovations in glass production, starting with the introduction of a pneumatic pump in England in 1859. This pump automated the glass blowing process, reducing it. number of skilled craftsmen. Chemical advances also have a strong impact on glass production, allowing manufacturers to change ingredients to create more sustainable products and better heat resistance. In 1871, William Pilkington invented an automatic sheet glass manufacturing machine using a cylinder-blowing method. This mechanization process was improved by JH Lubber in the United States in 1903.

By the turn of the century, glass makers realized that sheet glass could be me by heating it again and cooling it quickly. Thanks to the special stresses of glass materials, the durability of glass increases by about 400%. This is especially important for the automobile industry that is still in its infancy.

Cylindrical technology became obsolete when Irving Colburn (USA) and Emile Fourcault (Belgium) jointly developed new technology to pull molten glass from the furnace in small lines to form glass panels and cool them by pulling the glass tape. between two asbestos rollers. Although the glass produced by the "scissors" method is still rippled, it is the best quality sheet glass and it reduces the cost of products. In fact, in the 1920s and 1930s, due to "pulling" glasses dominating the market, the price of sheet glass was reduced by more than 60%.

Pulling technology also allows the production of flower glass by pulling the glass tape between the asbestos-printed rollers. Architects and builders quickly put flowers into a wide range of applications that require privacy.

In the years following World War I, the plate industry witnessed a strange growth thanks to the boom in housing and the automobile industry. By 1929, 70% of glass panels manufactured in the US were sold to the automobile industry. Many of them are safety glass produced by gluing two sheets of glass into an intermediate layer of acetate sel-lu-lot.

Although the production technology has been improved, the polishing stage to create high quality sheet glass is still the stage that requires much time and high cost.

Glass manufacturers around the world have sought to make high quality polished glass panels without additional machining.

The glass manufacturing industry only changed completely when Alastair Pilkington invented the modern float glass technology in the 1960s, minimizing the difference from polished glass. In Pilkington's technology, liquid glass in a continuous stream of continuous flow is poured into a shallow tank containing molten metal, usually tin. Liquid glass spreads on the molten metal surface and produces high quality glass tape with a stable thickness and heat-treated gloss. Pilkington's technology has revolutionized the worldwide glass industry in many ways. It significantly reduces the cost of sheet glass, creating new applications for sheet glass products such as interior decoration or building skyscrapers. With low cost, high quality glass has started to dominate the construction industry, automobile manufacturing, mirror industry. Today more than 90% of the world's sheet glass production is produced by Pilkington technology.

Modern development steps of the glass industry

In the 1960s, Pilkington's patented float glass companies improved their productivity and reduced glass prices, causing difficulties for companies that didn't have float glass technology. Until 1975, the number of float glass lines accounted for 97% of the glass production lines in the world, thereby confirming Pilkington's technology is one of the greatest inventions in the history of the industry. glasses.

Float glass technology produces many new technologies and new glass products. For the first time, high quality sheet glass is made with different thicknesses from 0.5-19mm or larger. The glass is made thicker for safety and noise protection purposes while ensuring the aesthetic standards. In addition, this technology allows manufacturers to change ingredients to make new products, including stained glass.

Due to the global energy crisis in the early 1970s, demand for sheet glass declined and affected the entire industry. For energy efficient reasons, glass is used less often in buildings. The housing construction industry is on the verge of a serious lag of the economy. Compact cars use less glass, and as if to make the situation worse, Ford Motor Co. began to produce float glass for their own needs, severely reducing the level of glass sold to the manufacturing industry. create cars. In fact, in 1970 Ford's Nashville company was the world's largest float glass manufacturer.

With many new technologies, the glass industry has met the growing demand for energy efficiency and new features. For example, with the study of light energy, manufacturers have created coatings that help the glass to receive sunlight and heat radiation more effectively, or possible sunlight control coatings. preventing heat from the sun in hot climates and still allowing him to transmit light. In 1970 low iron content glass for solar cells was born. These glass panels enhance the transmission of sunlight to help transform heat into electricity.

In addition, manufacturers have begun to introduce high- and medium-level reflective coatings, allowing architects and builders to achieve exceptional efficiency in light transmission and reflection. sunny or shade efficient. High-reflective glass products created from the deposition process in vacuum with the average reflective glass coated with pyrolysis have created a revolution in the late 1970s and early architecture architecture. 1980, building charming buildings with energy efficiency that we see around today.

Also in the 1970s, new requirements were set for the auto industry with many challenges. Manufacturers have produced more malleable glazing, which is the basis for the automotive industry to have new designs with a more aerodynamic look. In addition, safety goggles, first produced for cars in the 1920s - have become thinner, lighter, easier to shape.

Along with the improvement of the world economy in the early 1980s, glass manufacturers still strive to develop new technology to optimize the energy efficiency of glass windows. Undoubtedly, reflective glass is the biggest success of the glass industry in the last decade. In winter one can take advantage of the ability to absorb light energy, and also radiate heat from the heater back to the inside of the glass room. By increasing the temperature of the glass, water condensation is limited. These revolutionary products are increasingly positioned in the glass market. In fact, reflective glass products have increased by 13% since 1990.

Along with the development of technology towards energy efficiency, people are also focusing on the window processing industry. The rise of vinyl or argon-containing windows has set new demands for processing equipment. One of the key technologies in the late 1980s was the spacer system.

In the field of acoustics, new window designs have been created for houses in a noisy area. For example, some European manufacturers have assembled glass panels of different thicknesses to filter different sound bands, while others have added glazing to reduce noise pollution.

Nguyen Thanh - PKT TCT - Translated from Glass Journal