一旦选择了未煮熟的材料 , it must be sized appropriately so that fibers are of an ideal duration. Once this has been carried out, they're "carded" (punched into) into a good web with favored loft, density, and thickness before it's miles "needled" several times with barbed needles to interlock fibers into one solid cloth that has the preferred density and thickness preferred. The wide variety of needles relies upon upon density and thickness specifications favored by the customer.