It’s to wash something completely. About a futon, it means to remove futon covers first and then wash the futon with a large-sized washing machine. In the past, the cotton batting and the outer and lining fabrics of futons needs to be washed separately, however, it became possible to wash the whole futon because of the improved laundry techniques. By washing a futon completely, you can remove stains on cotton batting and dirt such as mite dead bodies, mite droppings and germs. And as a result of it, the elasticity of futons will get back.