Posted 02/03/2009 12:58 am
The PVC mentioned as in "pvc damage" is from the accumulated "plasticizer" chemicals in the polyvinylchloride plastic. With out these plasticizers, the vinyl plastic would be stiff and tend to crack easily. The plasticizers migrate from the plastic to the surface of the coin and attract moisture to form an acidic material which attacks the surface of the coin. The color can range from "milky" to blue, with copper usually greenish. Hopefully, the residue is removed with acetone before the coin is damaged by corrosion. There are several threads about using acetone to rinse coins.
The softest plastic flips have the plasticizers, but your coin is not going to be attacked within a short period of time. Often people use these soft flips for shipping or holding coins at a show where handling might slide the coin back and forth inside the flip. Less damage from the soft ones, but they should be in them for a limited amount of time.
However, once you buy the coin and have it on your own, it should be removed and transferred to a safer holder. Hard plastic holders like air-tites, albums, and also mylar or other plastics that have no PVC or plasticizers. Safety flips are in between hard plastic and the soft PVC types.
There are also many threads on 2x2 types of cardboard and plastic flips.
Hope this helps a little.
Use the search function for thread subjects.
Jim
