I had a quilt stored in a box of some kind of wood and it stained so I looked into the subject. Now, to store quilts esp long-term, I got some cardboard tubes from Joann's for free (2-3" in diameter and used two together for longer quilts), wrapped muslin over the tube first, then rolled the quilt (top up) over the tubing and rolled another layer of muslin over that. The quilts are stored in a closet where they are at an even temp. Seems to work fine and they can be shown off easily, no folds to worry about. Plastic, metal and wood seem to be risky.