The Ichorcloth Leggings are armor added by Thaumic Tinkerer. They are worn in the leggings slot and they have the same protection value as the Diamond Leggings but they are unbreakable. They are also resistant to fall damage (but does not negates it completely) and have 4% vis discount.
You have found how to weave ichorcloth into clothing. These new clothes are about as effective as mundane diamond armor, when it comes to protecting the wearer from damage. However, this cloth is completely unbreakable and will never sustain as much as a scratch.