Tableware, as an indispensable product in daily life, has always been the focus of consumers' attention for its safety and aesthetics.
Among the many tableware, ceramic tableware has been loved by consumers for its unique artistic charm and practicality.
Image source: The Paper
In ceramic tableware, overglaze and underglaze are two common decorative processes. So, is overglaze tableware safe? When buying bowls, is underglaze or overglaze better?
What is the difference between overglaze and underglaze?
First of all, we need to understand the basic difference between overglaze and underglaze.
The underglaze color process began in the Eastern Han Dynasty, which painted the color directly on the blank, sealed with glaze, and fired at high temperature, with soft color and safe and hygienic. The overglaze color originated in the Northern and Southern Dynasties, and its color material was painted on the surface of porcelain, and then covered with transparent glaze firing, with bright and diverse colors.
The underglaze color is painted with pigment on the clay tire after the blank tire is made, and then the transparent glaze or light glaze is applied and fired at a high temperature of 1200-1400 degrees Celsius, and the overglaze color is painted on the white glaze or colored tire porcelain that has been fired, and then painted with pigment, and then refired at 600-900 degrees Celsius.
Blue and white porcelain, a type of underglaze colored porcelain. The stock copyright picture, reprinting and using may cause copyright disputes
Pastel, a type of overglaze colored porcelain. The stock copyright picture, reprinting and using may cause copyright disputes
The two have their own characteristics in terms of decorative effect and craftsmanship, but there are certain differences in safety.
The glaze color tableware is bright in color, the pattern is diverse, and it is highly decorative. However, due to the direct exposure of the color material to the surface of the tableware, if the color material is not of good quality or the firing process is improper, it may lead to the precipitation of heavy metals, which can pose a potential threat to human health.
In particular, in order to reduce costs, some unscrupulous businesses may use low-quality pigments or paints, which may contain heavy metals such as lead and mercury. Long-term use of such tableware may cause these heavy metal elements to accumulate in the human body and cause an impact on human health.
In contrast, underglaze tableware is safer. Since the color material is wrapped in a glaze seal layer and does not come into direct contact with food, even if the color material contains heavy metal elements, it will not be easily precipitated. In addition, the color of underglaze color tableware is softer, giving people a feeling of warmth like jade, which is more in line with the aesthetic concept of Chinese. Moreover, because underglaze color tableware needs to be fired at high temperature during the production process, it also makes its surface smoother, less prone to bacterial growth, and more in line with hygienic requirements.
However, this does not mean that glaze tableware is useless. In terms of aesthetics and personalization, glaze color tableware undoubtedly has greater advantages. It can present a variety of patterns and colors to meet people's pursuit of beauty. At the same time, with the development of science and technology, the glaze color process has become more and more mature, and the quality of the color material has also been greatly improved. The safety of some big brands and manufacturers of glaze color tableware has been well guaranteed.
How to choose good porcelain tableware?
1
Observe the texture of the porcelain
Good porcelain tableware should have a delicate and uniform texture, with no obvious impurities or bubbles. When choosing, you can gently tap the porcelain to hear if the sound is crisp and pleasant, which usually means that the texture of the porcelain is tighter. At the same time, you can also touch the surface of porcelain with your hands to feel its smoothness and texture, and high-quality porcelain is usually more delicate to the touch.
2
Pay attention to the craftsmanship of the porcelain
The craftsmanship of porcelain is also an important factor in measuring its quality. High-quality porcelain tableware, its patterns, colors should be clear, bright, and smooth. In addition, it is also necessary to pay attention to the details such as the edge and bottom of the porcelain to see whether it is regular and smooth, and there are no obvious flaws or deformations.
3
Consider the safety of porcelain
When purchasing, you should try to choose products with regular brands and labeled "food grade". At the same time, you can also preliminarily judge the safety of porcelain by observing its color, generally speaking, porcelain that is too bright or too dark may contain too many heavy metal elements, and should be avoided as much as possible. In addition, it is best to wash and disinfect newly purchased porcelain tableware before use to ensure its hygiene and safety.
When choosing tableware, we should weigh it according to our own needs and actual situation and choose the most suitable product for ourselves. Let us enjoy the food at the same time, but also pay attention to the selection and use of tableware, to add more beauty and quality to life.
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Source丨Digital Beijing Science Center