The Soles Of My Husband's Feet Are Peeling Off Huge

The soles of my husband's feet are peeling off huge patches of skin. There is no redness or itching. It looks the way skin does when you've had a big blister, and the thick dead skin above the blister sloughs off, but it's the entire ball joint area, up the sides of his toes. It looks gross, but the skin underneath is perfectly healthy looking. He had that happen one time before about ten years ago.