Time varies a bit depending on the exact material.
Basically, exposure to what's typically considered display, framed and hung, or set out in a cabinet- any environment that offers easy and comfortable viewing- exposes an object to light, variable heat and humidity, and sometimes airborne chemicals. Most of them we'd call pollution, but the natural stuff like oxygen can be bad too.
T206s are on a pretty decent cardstock, and generally printed with good ink. So the effects are less than for some other items. The light fading the inks would likely be the worst part of things, with the potential to stick to the glass being second. I've removed a couple printed things stuck to glass and it's a bit tedious.
Newsprint is especially poor, even in really good storage. It's very acidic and degrades readily, becoming browned and brittle especially along folds.
One of the difficult things for collectors is balancing preservation with practical concerns. All the things stated about proper archival storage are correct. As are the comments about never looking at your cards. There's some happy medium for most collectibles, most cards will be fine stored the way most of us store them. In a binder on a shelf -not my favorite, as I find the pages slump unless I store them flat- or in a good quality holder in a box isn't a big problem. Just don't expect them to stay nice if they're propped up on a table in a sunny spot.
Institutions have a tougher time, often dealing with multiple types of items of varying materials, AND the need to allow access for display and research. As collectors we usually only worry about how things will be preserved within our lifetime. Museums have to worry about keeping things stable potentially for centuries(Some of the european museums have been active in some form long enough)
Steve B
|