WeChat official account is the number of the patent published by China National Intellectual Property Administration in the process of patent application before obtaining patent authorization. The announcement number is the number given when the patent right is granted. The patent publication number and announcement number in China consist of four parts: country number+classification number+serial number+identification code. AT the national level, two-letter country codes are usually used to identify countries, such as "AT" for Austria, "CN" for China, "EP" for Europe and "US" for the United States.