I've always been told not to put our quilts into plastic for any length of time as they can't breath. When I give a quilt as a gift, I try to make a pillowcase that matches with the leftover fabrics and I give them their quilt inside this pillowcase and tell them to store it in the case when not in use. It will keep the quilt clean and let it breath. Now that I think about it after reading about the sleeping bag I think I might have one in a plastic case a blanket or sheets came in. Will remedy that situation pronto. Thanks for the tip.