It sounds like you are asking about archival storage of woolen materials.

I'm personally twitchy about the mothballs/moth crystals idea. However I don't need to do archival storage of my kilts. They get way too much use. However ... When I am storing them (not on a hanger) I use the typical suitcase roll style. (someone makes a kilt roll bag actually).

I just can't see mothballs etc being good long term for the material. (Mothballs are bad, if you are using moth crystals which are slightly less bad you put them in a piece of nylon pantyhose and then store with the clothes in question. This keeps the moth crystals off the fabric.)

M.A.C. Newsome might the among best people to ask as he is with the Scottish Tartan Museum.