Under normal circumstances, the shelf life of carbon black is endless, but the processed carbon black products are best used within one year, especially the pigment carbon black series for coloring. The shelf life of carbon black is not unusable, which is different from the shelf life of food.
The main chemical formula of carbon black is C, and the chemical nature of C is inactive. Therefore, under normal circumstances, carbon black is not easily chemically reacted with other chemicals to decompose. This is also the reason why the shelf life of carbon black is endless.
So why do you say that processed carbon black products are best used within one year? This is mainly because carbon black absorbs moisture in the air until it reaches equilibrium. The humidity of carbon black is also an important indicator affecting the quality of carbon black. Therefore, carbon black is best stored in a sealed and dry environment. Even if the carbon black product is well stored, as time and weather change, it is inevitable that the deviation between its humidity and the factory default will affect its quality.
Is it only necessary to dry the moist pigment carbon black product and reduce its moisture so that it can be used again like the factory specifications? In fact, it is theoretically possible, but it needs to be elevated when drying. The chemical nature of C is becoming more and more active, and some chemical changes may occur, affecting other indicators of carbon black products.