Cotton Flannel can be woven in plain weave and napping can hide the weave
Flannel fabric is a soft, warm, loosely woven material, produced with a twill weave and featuring a napped surface. Flannel is believed to have originated in Wales sometime in the 16th Century, and was traditionally made from carded wool, although modern flannel can be derived from cottons, wool or a synthetic blend. Flannel is widely used for shirts and overcoats, as well as sheets for baby, pyjamas and long underwear. You can easily find tartan clothing, blankets, and bed sheets made of flannel fabric. Flannel is machine washable, and should be tumble dried on low.
Cotton flannel is a cotton fabric napped on one side or two sides. Flannel may be brushed to create extra softness or remain un-brushed. The brushing process is a mechanical process where a fine metal brush rubs the fabric to create fine fibres from the loosely spun yarns. Looking at the history, both the insulating warmth of the flannel material and the loose, non tailored appearance of flannel garments have appealed to various people such as musicians, tradesmen and skateboarders alike. Typically, flannel has either a single- or double-sided nap. Double-napped flannel refers to a fabric that has been brushed on both sides. If the flannel is not napped, it gains its softness through the loosely spun yarn in its woven form. Cotton Flannel can be woven in plain weave which napping can hide.