Talking about the shelf life of PCB

As far as the surface technology is concerned, chemical gold and electroplating gold have the longest storage time. The surface technology of HASL, electro-gold, chemical gold, and electro-silver is kept in vacuum packaging for 6 months under constant temperature and humidity conditions, while other Surface technology, such as immersion silver, immersion silver, OSP, etc., can generally be stored for 3 months. Among them, OSP (that is, anti-oxidation board) has the shortest shelf life. After opening the package, it is best to use it as soon as possible, otherwise the copper on the surface of the board will oxidize. Usually PCB boards It should also be placed in a dry and ventilated place, and avoid seasonal changes in sunlight and changes in temperature and humidity, which will affect the storage of PCB boards, especially humidity has a great impact on PCB functions, and will attack hole walls and surface metals. PCB manufacturers generally purchase vacuum packaging that affects the soldering effect. If there is a desiccant and other boards that are not used temporarily in the package, it is not necessary to open the package for better storage. For the board that has been oxidized, if it needs to be reused, it can be returned to the manufacturer for baking, reprocessing, etc. before use.