Seto-sometsuke ware Seto sometsuke yaki
Asbolite indigo blue on gentle, transparent white unglazed pottery
realistically expressing the Seto scenery
Seto Sometsuke Ware is a form of porcelain produced around Seto City and Owariasahi City in Aichi Prefecture. Dyeing is generally a technique of decorating porcelain with paint, but in the case of Seto Sometsuke Ware it also includes the application of dye to ceramics.
The characteristics of Seto Sometsuke Ware are its white unglazed pottery, which has an aura of purity and a soft texture, and its dyed pictures, which have an attractively realistic subtlety. The area around Seto City is famous for its production of potter’s clay, and locally produced forms of potter’s clay such as motoyamakibushi clay, motoyamagairo clay and sanage feldspar are used as the raw materials for this white unglazed pottery. Also, the dyed pictures drawn using asbolite, which is mainly indigo blue paint, depicts Seto’s natural environment and scenery.
The origin of Seto Sometsuke Ware goes back to the beginning of the 19th Century (during the Edo Period). It began when Tamikichi KATO, a potter from Seto Village (later Seto City), learned how to manufacture porcelain in Kyushu and brought the technology back to Seto. Porcelain painters then learned the Chinese-style art of painting from the various artists that visited Seto, and developed the ceramic painting craft of Seto Sometsuke Ware. It is said that production and decoration techniques were established in the middle of the 19th Century (during the Edo Period). The art of painting established at this time, depicting Seto’s scenery and nature in Seto Sometsuke Ware, was highly praised at the World Expos held in places such as Paris and Vienna from the end of the 19th Century to the early part of the 20th Century (during the Edo Period), and it also influenced the Art Nouveau movement in Europe.
Going into the Meiji Period, the production of Seto Sometsuke Ware prospered even more. In addition to tableware and stacked boxes, large products such as tables, hanging lanterns and flower vases were produced. This production continues steadily down to this day.
General Production Process
- 1. Mixture of potter’s clay
The raw materials of Seto Sometsuke Ware include characteristically viscous Seto-produced motoyamakibushi clay and motoyamagairo clay as well as translucent sanage feldspar. Potter’s clay with Seto Sometsuke Ware’s characteristic softness is produced by blending several types of raw materials.
- 2. Formation of unglazed pottery
Potter’s clay is cast using techniques such as lathing, where work is performed on top of a circular rotating stand; closed die forging, where unglazed pottery is pressed against a mold; and forming by hand, where models are cast by hand alone. After casting, the thickness of the unglazed pottery adjusted by planing, and the surfaces are cleaned by wiping with a cloth or sponge soaked in water.
Patterns may also be applied at this time. Traditional techniques include kakka, where patterns are engraved with a plane or spatula, and inka, where patterns are applied by pressing a seal stock.
- 3. Drying/bisque firing
Unglazed pottery that has been cast is dried and undergoes bisque firing at a low temperature of around 850°C.
- 4. Dyeing (undercoating)
Undercoating is applied to unglazed pottery before glazing with enamel. In the case of Seto Sometsuke Ware, the use of dyeing techniques for undercoating is a characteristic feature. Dyeing involves directly painting pictures onto the unglazed pottery using a paint known as asbolite, which is produced mainly from oxidized cobalt pigment. There are various types of painting, and leading examples include line drawing, in which pictures are outlined with thin lines; dami, in which shading is performed by painting inside the line drawings; and tsuketate, where pictures are painted freely without outlines.
- 5. Glazing
After dyeing, enamel is applied to the unglazed pottery using methods such as soaking, dipping and paintbrush application. The main type of enamel that is used is lime glaze, which has transparency and glossiness. Other types of enamel that are used include celadon porcelain glaze, azure glaze and oak ash glaze.
- 6. Drying/firing
After drying the glazed pottery, the next process is glost firing. Seto Sometsuke Ware has a characteristic soaking process, which is carried out in the final stage of firing. Soaking involves maintaining the kiln temperature at around 1,250°C for a fixed period of time to cure the enamel.
- 7. Completion
Once firing (including soaking) is finished, pots are removed from the kiln and the Seto Sometsuke Ware is complete.
If overcoated patterns are to be added, it is performed after glost firing. Gold, silver and other new coloring is applied using painting techniques such as line drawing and dami, where undercoating is also used, and the pieces are fired at a low temperature of 700 to 800°C.