These subsequently evolved into round portable cushions woven from rush or straw into round spiral shapes and then in the middle of the Edo Period zabuton made from cotton stuffed into material bags were created.
これが後に円座（イグサや藁を綱とし、円形・渦巻状に編み上げた物）のような持ち運びに簡便な道具に代わり、江戸時代中期に布の袋に綿を入れる様式となったとされる。