Sateen is a cotton fabric with a satin-like finish, often found in bed sheets.
Sateen is usually made of cotton, or sometimes rayon. Better qualities are mercerized to give a higher sheen. Some are only calendared to produce the sheen but this disappears with washing and is not considered genuine sateen. Sateen may be bleached, dyed, or printed. It is difficult to make good bound buttonholes on it as it has a tendency to slip at the seams.
In Australia it is often referred to as "Moleskin".
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