When and where is porcelain found?

These first known specimens of true porcelain were made in China in the 6th century AD. The techniques for combining the proper ingredients and firing the mixture at the extremely high temperature gradually developed out of the manufacture of stoneware.For centuries, the Chinese made the world’s finest porcelain. Collectors regard many porcelain bowls, and vases produced during the Ming dynasty (1368-1644) and Qing dynasty (1644-1912) as artistic treasures. Porcelain makers perfected famous blue and white under-glazed porcelain during the Ming dynasty. During the Qing period, the Chinese developed a great variety of patterns and colours and exported porcelain objects to Europe in increasing numbers. The term porcelain appears in the writings of Marco Polo who visited China in the 13th century.

What is Porcelain?

Porcelain belongs to the large group of materials called “ceramics”.It is characterized by a hard, whiteness, translucent, impervious, resonant ceramic body. There are three main types of porcelain:

• Hard-paste porcelain
• Soft-paste porcelain
• Bone China.

What is the different between “ceramic” and “porcelain”?

The word ceramics comes from the Greek keramos, meaning “potter’s clay”, this refers to both the material and the products.Ceramics range in texture from coarse, such as plain clay tile, to progressively finer products such as earthenware, majolica, faience, and stoneware, to porcelain. Porcelain is the finest textured of all ceramics.It represents the ultimate in ceramic quality and beauty.

Porcelain differs from other types of ceramics in its ingredients and in the process by which it is produced. Ceramic – earthenware and stoneware—are made from single natural clay which is then baked. Porcelain is basically made from mixture of kaolin and feldspar breaks down.This mixture is fired at temperatures from 1250°C to 1450°C.At these extreme temperatures, the petuntse vitrifies – that is, it melts together and forms a nonporous, natural glass. The kaolin does not melt and therefore allows the item to hold its shape. The process is complete when the petuntse fuses itself to the kaolin.

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What is Hard-paste Porcelain?

Hard-paste porcelain is the type of porcelain first developed by the Chinese from kaolin and feldspar. It resists melting far better than other types of porcelain. For this reasons, it fired at high temperature cause the body and the glaze to become one. It is impossible to distinguish the body from the glaze of hard-pasted porcelain when it broken into piece.

What is Soft-paste Porcelain?

Soft-paste porcelain, also called artificial porcelain. It was developed in Europe in an attempt to imitate Chinese hard-paste porcelain. Experimenters used a wide variety of materials in their efforts to produce a substance that was hard, white, and translucent. They eventually developed soft-paste porcelain by using mixtures of fine clay and glasslike substances. These materials melt at the high temperatures used in making hard-paste porcelain. For this reason, it fired at lower temperatures and does not completely vitrify—that is, it remains somewhat porous.When a soft-paste porcelain reveals a grainly body covered with a glassy layer of glaze.

What is under-glaze Porcelain?

Under-glaze is a technique where porcelain maker painting the blue cobalt on the air-dried body, the glaze thinly applied, and the whole object finished with one firing at intense heat.

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What is on-glaze Porcelain?

On-glazing not like under-glaze, the air-dried body glazed and fired at high temperature around 1300°C to 1450°C. Painter then decorate it by enamel designed pattern and colour on the piece.Most of the enamel colours are made from metallic oxides, such as iron, copper, and manganese.Enamel colours require a second firing to make them permanent. The firing temperature for on-glazed piece is determined by the melting point of the glaze’s colour which is 750-900°C.In this process, the decoration is fused onto the glaze; thus the term “on-glaze”.

What is in-glaze Porcelain?

In-glazing is a technique for permanently protecting decorated porcelain pieces from normal mechanical and chemical stresses. Artisan first decorates porcelain pieces by transferring or sliding screen-painting designs or hand-paint onto smooth-fired porcelain bodies.Then they add appropriate metal oxides and liquids to the glaze to achieve the desired colour effect. Next, craftsmen fast fire the pieces at 1200°C-1300°C. During this firing, the decorative design is sealed under the glaze, or embedded within it, thus the term “in-glaze”.

What is Transfer printing Porcelain?

Transfer (decal) printing revolutionized the porcelain industry in 1756 by enabling workers to decorate wares much faster than by hand-painting. In this process, a design is engraved on a copper plate, inked with ceramic colour and transferred to tissue paper. While the colour is still wet, the tissue papers of pressed against porcelain object, leaving the design on its surface.Transfer printing allows mass production of porcelain in relevant low cost and uniform quality.

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How is glaze applied to porcelain?

Glaze is milk-like liquid. Craftsmen dip and wash each porcelain piece in the glaze, which remains on the surface like coating of flour. Artisan wipes the pieces with moist foam rubber strips to remove glaze from those contact points which will rest on a porcelain setter. This setter supports the glazed piece during the firing process and then discarded.

Why glaze applied to porcelain?

Glazing allows the piece waterproof. The smooth-fired porcelain body may coat with colour-enhanced glaze to decorate and also provide good hand feeling not rough surface.

Why does a piece of porcelain have rough patches?

Rough patches on porcelain pieces are inevitable because of the nature of the firing process. Under the high heat of firing, the porcelain glaze becomes highly viscous and sticks to the surface of the disposable porcelain setter. Leaving rough patch allow the piece lifted from the setter after fired.

How long does porcelain decoration last?

In-glazing permanently protects porcelain decoration from all kinds of external mechanical and chemical stresses as the decoration is sealed under or embedded within a hard durable glaze.

On-glazing fuses the decoration onto the glazed piece. Since decoration is more exposed to external stresses, it is more susceptible to damage.

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