apart from the cleaning problem, that is the quality problem of the tableware itself. Some dishwashing factories use Grade 2, and the black spots are produced by minerals in the mud during the firing process. Because it is fired at a high temperature of 1,311 degrees, there is no problem, but it looks unsightly. The main reason is that the competition pressure in this line is high and the delivery price is low, so the dishwashing factory has to find a way from the source.