Process of Mino-yaki
This time, we visited Nippoutouen, Gifu prefecture.
Usually, taking pictures of the kiln is not allowed, however, we are given permission of taking pictures. Most people don't know that how are these products produced if customers use the Japanese tablewares on daily basis, so we would want you to know these processes.
First, we observed the process of forming. Clay is set on the wheel which is rounding, then it is formed by centrifugal force. Each one is finished up quickly. Moreover, baked color is different each one because the clay has many property and color.
After forming, dry it for three days, moreover, it fires to remove moisture from clay. The bisque process continues for two days at a temperature of 800 degrees.
Even tiny dust affect workmanship negatively, after taking dust by blowing air underglaze painting is started by writing hands. The pictures show that is painted by spraying and make a line which is called Senbori.
At this process, pottery and porcelain are applied glaze which contains color and makes glass coating after the fire. There are about one hundred kinds of glaze, it is arranged by outdoor temperature, humidity and weather. It is very delicate, so it is likely that color is not the same color every time. This is an interesting point of pottery and porcelain because nobody knows the result of baking pottery and porcelain.
This company has a tunnel kiln and a shuttle kiln. The tunnel kiln works every forty minutes, it takes twenty - two hours to fire. The image is like trains run on a rail. Pottery and porcelain fire at about one hundred eighty degree celsius. Coming out objects from tunnel are hot and fresh like getting burn. The image of shuttle kiln is bakery store. Different from bread is that shuttle kiln of pottery keeps closing the door in order to cool down. The period of fire is twenty - two hours which is the same time as tunnel kiln, however, these potters don't come out for two days because it includes period of cooling time.
In the past, people had had imagine that a smoke coming from chimney represent this industry, however, gas tanks shows place of the kiln today.
This process is checking and fixing the quality of firing such as unstable object. Although workers really take care products, the result changes each time because of depending on the weather so this is the hard process. If the new design is produced accidentally, it becomes a one-off piece because it is hard to reproduce again.
In the case of drawing picture after fired, it is fired at low temperature and a short time in order to avoid to disappear the picture pattern. In particular, it is fired at eight hundred degree celsius for six hours.