1. Insoluble or insoluble in foaming solution In order to break the foam, the defoamer should be concentrated on the foam film. For defoamers, they should be concentrated and concentrated in an instant, while for foam suppressants, they should be kept in this state regularly. So defoamers are in a supersaturated state in foaming liquids, and only insoluble or poorly soluble ones are prone to reaching supersaturation. Insoluble or difficult to dissolve, it is easy to aggregate at the gas-liquid...

China has been producing ink for a long time. The predecessor of ink was pine ink. China uses pine smoke, glue (mainly cowhide glue, which plays a role in bonding cigarette ash), and water to make black ink. Started as a writing tool and later used in the woodblock printing industry. Ink developed rapidly in the early stages of China, but after the Middle Ages, it remained stagnant and satisfied with traditional secret formulas, lacking creativity. At that time, wooden printing in Europe was...