Posted 06/22/2019 11:02 am
Soft PVA flips OK for a short time.
Dealers send coins through the post in soft PVC flips all of the time.
Not OK for the longer term, especially for bronze coins and to a lesser extent, silver coins. The softener gasses out over the longer time, and may chemically react with the coins in the flip, which is in contact with the PVC.
Use PVA (Acetate) or Mylar materials instead. PVA is used for food storage (found in supermarket food packaging), so it is OK for coins as well.
Mylar is the clear material used in cardboard flips. Also used in thicker semi stiff sheet in banknote albums.
For extra protection, I sometimes make a 1.8' x 1.8" PVA flip, and put that inside a standard Mylar / cardboard flip. Do that mainly with softer gold coins to protect them from physical impact with other coins in the album.
Dealers send coins through the post in soft PVC flips all of the time.
Not OK for the longer term, especially for bronze coins and to a lesser extent, silver coins. The softener gasses out over the longer time, and may chemically react with the coins in the flip, which is in contact with the PVC.
Use PVA (Acetate) or Mylar materials instead. PVA is used for food storage (found in supermarket food packaging), so it is OK for coins as well.
Mylar is the clear material used in cardboard flips. Also used in thicker semi stiff sheet in banknote albums.
For extra protection, I sometimes make a 1.8' x 1.8" PVA flip, and put that inside a standard Mylar / cardboard flip. Do that mainly with softer gold coins to protect them from physical impact with other coins in the album.
