DLI’s Garment Analysis Laboratory has seen many white silks that are yellowed from alkaline spotters and detergents. The lab had two cases in which off-white silk wedding gowns were wetcleaned in an alkaline detergent. The gowns were very badly yellowed and in one case the yellowing was permanent.
Whether you are cleaning wedding gowns worth thousands or a blouse worth twelve dollars, the basics for wetcleaning and spotting silks are the same.
- Use neutral detergents for wetcleaning and spotting.
- Alkaline spotters can be used on silk and wool if they are rinsed thoroughly and neutralized with a mild acid such as a tannin formula or 28% acetic acid.
- All prespotted/spotted areas must be thoroughly dry before cleaning.
- If bleaching is necessary, use hydrogen peroxide oxidizing bleach for organic stains (beverages, perspiration, urine, etc.) or any reducing bleach for dye stains.
- Digesters are preferred for heavy build up of albumin stains (blood, milk, cream, etc.).
For more information on removing stains from silk see DLI Bulletin Fabrics and Fashion 494: Stain Removal Procedures for Silk Fabrics in DLI's Drycleaning Encyclopedia.