Silk is protein fiber, more similar to wool than to cotton. It is very similar to human hair. Remembering this will help when you think about how to wash or clean it.
Silk is extremely strong, butrepeated exposure to the sun will erode the fiber. As a result, silk fabrics are poor choices for curtains and draperies.
In general, silk can stand heat (it is subjected to very high temperatures when the gum is removed, and most silk dyes are steam set), but does not do well in extreme changes of temperatures, or in overheating through excessive drying.
Some silk yardage and clothing can he hand washed if done carefully. For best results use a mild detergent (like Woolite, or even shampoo) and lukewarm water, then roll the fabric in a towel to absorb the water. Do not twist just as you wouldn't twist or pull your hair. Iron dry on a low setting. If you're unsure about washing, check with the manufacturer when possible. Many manufacturers will tell you to dry-clean because it is simpler and yields better results. Where ever possible, you may want to check a swatch first.
Structured silk garments and fragile fabrics should be dry-cleaned to prevent damage. Multi-color prints or hand-dyed scarves may need to he dry-cleaned to prevent running. You may wish to dry-clean your garment the first time. The steaming process used at the dry-cleaners many also help to further set the dyes.
Moths will attack silk, as well as wool. Store your silk clothing appropriately. As with all fine fabrics, if you plan to store for a long time, you will do best to store in a cotton pillowcase or otherwise surround the silk with a fabric that can breathe. Avoid storing in plastic since this can trap moisture, which can lead to yellowing or the accumulation of mildew.
Never use chlorine bleach on silk. It will yellow the fiber and may cause it to breakdown more quickly.
The colors in your silk will undoubtedly fade over time, even when permanent dyes have been used and they have been professionally set. Reds are particularly sensitive to running and fading. Store your silk away from exposure to light, especially direct sunlight. Washing silk may also cause excess dye to discharge. When in doubt, dry-clean the garment or item.