It may depend on where the quilt will be living...

I know of areas where the bedrooms can get below freezing during a portion of winter when the outdoor temp is -40 or more. Quilts are stacked up on the beds, heads buried under the covers, and water will freeze in a glass.

Quilts taken on winter camping/hunting trips...
quilts left in semi trucks when the driver takes a day or more off, the inside can easily get below freezing...
Quilts left in cabins for the winter...

I think I will have to experiment a lot with these before trusting that they won't need ironing on a regular basis til the ink quits reappearing :D:D:D