I don't know about using Dawn or even Ivory dish washing detergents for washing fabrics-especially quilts. Or even the most favorite stated preference here, Synthrapol. I always use the Arm and Hammer laundry products for all my regular and fine laundry wash. Including the quilts. Especially considering the rather harsh hard mineral deposit water that is locally available where I live. They work and work well all things considering. Plus these products are very affordable. I believe that the "secret" ingredient is baking soda (Sodium Bicarbonate) that I use liberally. I buy a box of "baking soda" just for rinse cycles ending in the final rinse as well as an extra one for the wash cycle if extra dirty. Your grandma's quilts were washed with this product, why not your own as well?
Sensitive Skin-Perfume & Dye Free
http://www.armandhammer.com/fabric-c...-dye-free.aspx
Delicare:
http://www.armandhammer.com/fabric-care/fine-fabric-wash/Products/delicare-fine-fabric-wash.aspx