About Iznik Panels
A- Ceramic Body Material,
Traditional Turkish ceramic tile and pottery designs are applied on different ceramic body recipes.
1- Traditional Iznik ceramic bodies, or Iznik wares (they have very high quartz content up to 80-90% with a firing temperature within 900-1050 °C).
2-Kutahya Ceramic bodies, or Kutahya wares (they have relatively low quartz content which fall within 30-35% with a firing temperature of 950-1050 °C).
3-Ceramic bodies Industrial tiles and pottery (they have very low quartz and high clay content within a firing range of 1100–1250 °C.
4-Porcelains, non porous white tablewares with a firing temperature range within: 1250-1400 °C
1-Iznikwares (High quartz content)
Iznik wares have the best body durability. Quartz is a semi precious gemstone. Because Iznik wares have a very high content of quartz which is non plastic and its percentage in recipe is up to 90%, forming them is very difficult. If this difficulty is overcome there is another one which is firing. Firing is too risky and too many items are come out of the kiln with a lot of defects.
When the old ceramics are investigated it can be easily understood that in the past ceramic artists encountered similar serious problems mentioned above. There wasn’t a standard production in the past. But nowadays with the help of modern laboratory work and equipment a high level of production quality -although it is not as high as industrial ceramic production- has been achieved.
Iznik wares -because of their high quartz content- are not affected from water, moisture, chemicals and temperature changes. Therefore they can be used in indoors and outdoors safely as they have been used in the past. Iznik wares have a sponge like structure which absorb and leave water easily. Therefore they can stay for hundreds of years without any formation of defects. The designs are under the glaze and protected therefore they do not fade away for hundreds of years, therefore sometimes Iznik ware panels are called “non fading blossoms of Paradise”
Iznik wares are usually hand painted. After first firing they are rarely printed with silk screens. Then they are glazed and fired. When compared with other ceramics they have a bluish body color which is usually called as “eye white” and people who look at them have a feeling of depth. Traditional Ottoman Pottery samples have exactly this appearance and are very appealing. Because of their production difficulty and having a high production risk, their cost is very high.
(Low quartz content)
3-Industrial Ceramic Bodies
designs can also be applied on industrial wall tiles. These tiles have very
economical price with respect to traditional tiles, namely Iznik and Kutahya
wares. They can be used outdoors and humid places safely. There are two
methods of design application on industrial wall tiles:
On glaze and in glaze application.
On glaze applications are applied on fired and glazed ceramic wall tiles with printed ceramic films called “decals” or the designs can be hand painted on glazed ceramic tiles. The firing temperature is quite low which is between 800-850 °C. But these wall tiles can not be used safely outdoors and humid places like Turkish baths and saunas. Because the designs are not covered they can wear in time.
In in glaze, applications are similar to that of on glaze firing. But the firing is performed at higher temperatures and the stains sinks in the glaze and the designs become permanent. They can be safely used in the decoration of outsides of mosques, humid places like Turkish baths, saunas and pools.
The durability of the designs can be tested with a method called acid test. When the designs do not fade after acid they are considered as high quality ceramics.
4- Porcelains (are usually used as tablewares)
Traditional Iznik designs and patterns are also applied on Porcelains. Porcelain technique is similar all over the world. The designs are usually applied on the glaze. Under glaze decoration is also possible but they are not as glossy as Iznik and Kutahya wares. The decoration wears out in time after repeated utilization. Most of the tablewares used in homes are produced with this technique. We usually apply this technique on Turkish coffee cup sets. Porcelain tiles are not utilized widely because of their high cost.
C-Application of Designs
There are 4 different decoration techniques which are applied above mentioned bodies:
1-Hand painted under glaze decoration: This technique is used in production of Iznik and Kutahya wares. The shaped bodies which are called biscuits after first firing are decorated with classical Turkish designs and patterns with sable hair brushes. Then they are glazed and fired at about 950°C. The designs remain under a protective glossy glass layer called glaze. Colors are bright and very vivid. This is the classical technique used in the production of traditional Turkish ceramics.
2-On glaze hand painted decoration: The designs are painted on the glaze. This is a widely used easy technique. Since the colors are on the glaze they are not bright and vivid. They may wear out in time.
3-Underglaze silk screen printing: These are made by application of designs on Iznik and Kutahya wares by silk screen printing. The designs are applied on the “biscuits” after first firing, glazed and fired again at 950°C. The designs are under the protective layer of glossy glaze. Colors are bright and vivid like in hand painted ones. They are not very valuable because of their mass production. They are preferred by customers and suppliers because of their low price in mass production. However when special designs with limited quantity are demanded, their cost may also be as high as hand painted ones.
4-On glaze silk screen printing: A low cost technique applied on industrial wall tiles and porcelains. However since the colors are on the glaze and not covered by a glossy layer of glaze they are not bright.
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is prepared by Salim Sabancilar it can not be used without his .prior