In this post, glaze vitrified tiles manufacturers will explain the significance of glazing technique and how it helps them achieve desired finish in a tile.
Glazing is a type of coating used to make vitrified surface smoother by sealing the porosity of earthenware or ceramic products. It is often a kind of dense metal fired at high temperature and coated over the terracotta, porcelain, ceramics, stoneware, and earthenware products. Glaze is used mainly to cover the porosity but it also serves in different types of coating for surface finishing. Let it be matte or glossy finish or it can be a different color addition to the surface with texture and design creation underlying its coating.
Glazing a ceramic or vitrified tile along with stoneware and porcelain becomes a common practice by the time and is in use by almost each and every country where these products are manufactured. Not only pottery products but common domestic sanitary ware made of ceramics or porcelain are also glazed and coated with one or the other glazing material. Common materials to be used in coating and glazing are as below.
- Ash Glaze is most often used to glaze ceramic products. These are retrieved from the ashes of wood and straw plants. This is also the most traditional way of glazing and has its own history in Chinese pottery as well as in East Asian, Japanese, and Korean pottery industries where ash glazes have been an important way to glaze ceramics and have been experimented so often to form natural glazing. The most common way still is to mix ashes with clay and coat it in form of a paste.
- of ash, glazing goes back to Shang dynasty when it is known to be discovered by mistake when ashes from firing woods nearby flew upon the pots and caused the glaze effects. Soon after the incident potters got to understand that ashes can cause this effect by a coat on pottery. Soon they started mixing ashes with clay before it went to the fire.
- Feldspathic glaze is a product of feldspar crystals formed by magma crystallization present in intrusive and extrusive igneous rocks. It can also be retrieved from metaphoric rocks formed of calcic plagioclase feldspars and sedimentary rocks. Feldspar is derived from a German word which means field flacks and is found commonly in German field provenience of granite and other minerals. These pled spars groups are divided into categories like
- Potassium Feldspar
- Alkali Feldspars
- Barium feldspars
- Plagioclase Feldspars
- Lead Glaze is the most traditional glaze type to be used on terracotta subjects which makes it impervious to liquids. Lead glaze is shiny and often transparent or translucent depending on its color. Lead glazes were used in making high-quality oil lamps by the Romans whereas it has been used in sancai ceramics of tang dynasty almost the same time to make three colored effects on ceramic subjects by coating colored glazes over the simple white-colored clay and then firing them in approx. 800 degrees of temperature gave this stunning color effects. Sometimes copper has also been used to give polychromic effects to ceramics. Different metals were used to get different colors with the glazing effects like Cobalt for blue, Manganese for brown, Iron for brownish-yellow, and copper for green color effect.
- The salt glaze is known to be used by Germans in the fifteenth century when common salt is been threw in the kiln during the high temperature firing inside. It certainly had a chemical bond with the silica of clay body and formed sodium silicate layering over the clay body and formed a new glassy layer almost transparent and shiny yet less costly than the previous methods of glazes. Later on a few more corrections been done to get different colors while the glazing process with use of metal ores like Iron oxides to get various shades of brown color, cobalt oxide for blue, and manganese oxide for purple colors respectively.
- Tin glaze has been used for mainly pottery purposes around the world since ninth century as known. This is basically lead glaze mixed with tin oxide to make it transparent and shine to cover the beautifully painted surface of the clay. First, known pottery was made in Iraq and it took almost six centuries till it reached Italy in almost the mid-fifteenth century and before that it was already in use by Egyptians, Persians, and Spanish. It was found in Holland in the around sixteenth century and shortly after that, it was also seen in France, England, and other European countries. Tin glaze has been in so many cultures and timelines that it got different names with slightly changed chemical formations in different parts of the globe.
- Hispano-Moresque ware
- Maiolica or majolica
- English Delftware
Modern-day Enamel glaze is mainly made of powder glass substation by firing it in around 750 to 850-degree temperature and melting it to flow and get coated on ceramics or porcelain where it then hardens to form a vitreous enamel coating. This coating can be done on metal, ceramics, and even stones that can withstand the fusing temperature while the coating process.
For more details, you can ask Polished porcelain tiles manufacturers at any time. The experts working in the foundry will be glad to assist you.