Pink stain is a common problem on marine fabrics such as seating cushions, upholstery flooring and other vinyl surfaces. Once the stain happens, it cannot be cleaned. However, there are ways to prevent pink stain in the first place, through either preventing the growth of the bacteria that causes it or by sealing the substrate with a coating.
Before addressing prevention, it is important to make a distinction between “pink stain” and “pinking,” which are two separate, unrelated issues. Pink stain is caused by bacterial activity on plasticized vinyl, while pinking is caused by chemical reactions associated with polymer over-heating and/or the action of air pollutants on polymer surfaces.