Silk is a delicate natural fabric that can be permanently ruined by harsh chemicals such as silk. Though we have been accustomed to bleaching anything white, bleach is too strong of a chemical for natural fabrics. Natural fabrics, such as cotton, silk, and linen perform best with natural ingredients.
We recommend using white vinegar for washing your Mismatch silk pillowcases (and cotton sheets) instead as a safe eco-friendly option. White vinegar is a great substitute for bleach because it contains acetic acid that works to brighten, soften, and kill odors. Just add 1/2 a cup to your load and wash and dry as usual.