[mcgwirecom]

If you are talking about YEARS of storage I wouldn't leave them on hangers unless they are well padded with some kind of acid-free padding. Over long periods of time anything that touches something else may cause it harm. They sell acid-free boxes that you can loosely fold the jersey in. I think they have acid-free tissue paper to wrap it in also. Just make sure to keep it away from dampness and climate changes. No attics or basements unless they are controlled.

It's always good to think long term when storing expensive items. I have several guitars and in the winter I have to keep an eye on the humidity levels. I bought a bunch of cheap humidity gauges to make sure it doesn't get too dry. Guitars can dry out and crack if they get too dry over a long period of time.


I found this online...

7. Ideal textile storage is flat with as few folds as possible. Space limitations do not
always allow storage without folds. Pad all folds, puff out bodices, sleeves, and
ruffles with rolled non-buffered acid and lignin free tissue paper. Fibers tend to
break on fold lines or creases-so padding these areas and yearly refolding helps to
prolong the integrity of the textile. Knits, bias cut, and beaded garments will not
survive long term hanging storage. For large, flat items such as quilts and table
linens, a sturdy cardboard tube wrapped with mylar and covered with non-buffered
acid and lignin free tissue or washed muslin can be used to roll the item, being
careful to smooth the items as it is rolled. Never fold items before rolling. An outer
protective dust cover can be made of washed, unbleached muslin.
8. Although flat storage is preferred, some items are too bulky to store flat. If an item
must be stored on a hanger, cover the hanger with polyester batting and cover that
with washed, unbleached muslin. Use muslin or non-buffered acid and lignin free
tissue to pad sleeves and folds. To relieve shoulder stress, make cotton twill tape
suspenders tacked to the inner waist seam to evenly distribute the weight of a heavy
skirt on the hanger. Cover with a loose fitting bag made of washed, unbleached
muslin to shield the item from dust and light. Do not use metal wire, satin, or foam
covered hangers. The satin and foam are unstable and will degrade fibers. The
metal does not provide sufficient support, it might rust, and can sometimes initiate
deterioration in wool or silk items.
9. Always use acid and lignin free materials. Washed, unbleached muslin, white
100% cotton sheets, non-buffered acid and lignin free tissue and acid free boxes are
good materials to use when storing textiles. Acid free materials are available
through many archival supply companies (see supply source list). Just because a
company uses the term “archival” does not mean the products are safe. Always
check for acid and lignin free materials. Do not use colored tissue paper. The dyes
from the tissue may migrate into fabric and may be impossible to remove.
Moreover, the acids in the tissue paper (even ordinary white tissue) are very
damaging to fibers.