Oshima tsumugi is also referred to as kasuri–a Japanese word which implies “hand-tying.” The cloth is perhaps the world’s finest double ikat: a technique of dyeing threads for a fabric with the final design before they are woven together. For Oshima tsumugi, both the warp (vertical) and the weft (horizontal) threads are resist-dyed. Even in its most simple incarnation, the ikat technique requires a great deal of skill and planning to execute.
And the website http://handeyemagazine.com/content/sustaining-tradition-0