Almost all epoxy resins
have a shelf life of 12 months (from the date of production). In fact, the validity period of epoxy resin adhesive itself is much longer than that of curing agent, even resin can be used well within three years from the production plant. But the anhydride curing agents for epoxy resins
will begin to deteriorate significantly after 12 months.
If it is guaranteed that it will not be corrupted, epoxy resin can be used for several decades. If it refers to the yellowing resistance time, it can generally be maintained for 7-8 months outdoors. If it's indoors, it's OK for a year.