Writing and drawing with expired ink will be smudged, which will affect the calligraphy effect. So calligraphers generally don't store ink, but collect Mo Ding. Mo Ding is characterized by stability, which can last for decades or even longer. However, the ink quality of Yidege is good, and the ink that has not been opened for more than ten years is still very good. Some brand inks with good quality have a longer storage life.
2. Composition of ink: The main raw materials of ink are soot, rubber compound, additives and solution, which are generally machined. There are many kinds of soot, including various mineral plants and animal raw materials, which are formed by combustion or thermal decomposition. In addition to animal glue, vegetable gum (Arabic gum) or various synthetic gums such as acrylic gum and polyol resin are also used as glue. Additives include various stabilizers, penetrants, wetting agents, preservatives, essences, etc. The quality of gum is very important and plays a decisive role in the shelf life of ink.