Is satin ruined if it gets wet?

Satin is not automatically ruined if it gets wet, but the risk depends entirely on the fiber content. Polyester satin, which makes up the vast majority of satin clothing, lingerie, and bedding sold today, is not ruined by water at all. Polyester is a synthetic plastic fiber that is hydrophobic, meaning it repels water, does not shrink, does not lose strength when wet, and dries very quickly. You can machine wash polyester satin in cold water and it will be fine, though hard water can leave marks and high heat can damage the weave. Silk satin, however, is much more vulnerable to water. Real silk is a delicate protein fiber. Water can cause permanent water spots, make dyes bleed or create tide lines, cause slight shrinkage, and weaken the fibers if you rub or wring it while wet. Chlorinated water, perfume, and sweat can also stain silk satin. That does not mean a little rain instantly destroys it, but improper washing can ruin its luster and texture. For silk satin, you should dry clean or hand wash in very cold water with a silk-safe detergent, never wring, and air dry away from direct sunlight to avoid damage.