Why Do White Clothes Turn Yellow in Storage?

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The mysterious yellowing of clothing in storage remains a common conundrum among archivists and housewives alike. Clothes may be freshly washed and pressed before storage, but several months or years later display unsightly yellow stains or a dingy hue. Despite the seemingly dormant season of storage, ongoing invisible chemical reactions and decay change the bright white to a yellow cast.

Too Much Bleach

Household bleach will whiten clothing, but too much bleach will cause them to yellow. Bleach is a harsh disinfectant; too much of the chemical in the wash load will cause fabrics to deteriorate and yellow over time. Dan Eisen, former chief garment analyst for the Neighborhood Cleaners Association recommends an application of distilled vinegar to the rinse cycle of a bleached load will neutralize the bleach and prevent yellowing.

Insufficient Detergent and Washing

Insufficient washing or detergent during the launder cycle will allow dirt and debris to remain embedded in the small fibers of the clothing. In storage, this debris may decompose, leaving behind unsightly stains or spots. Thorough cleaning and drying before storage of whites will help eliminate yellowing.

Insufficient Rinsing

Most clothing laundered with a washing machine endures a cold-water rinse cycle. Cold water may cause soap scum to congeal and form a thin coating on the clothing. In storage, this coating may cause the white fabric to turn a light yellow color. A special laundry additive called "bluing" may be added to the final cold-water rinse cycle to prevent the yellowing of clothing.

Whitening Agent Decay

White is a dye; clothing manufacturers dye white clothing white with whitening agents. These whitening agents may decompose while in storage, leaving behind a yellowish cast to the clothing. Usually the white color can be restored with a new treatment of a commercially available whitening agent through a wash load.

Acids in Storage Containers

Inert compounds in storage containers such as plastic boxes, cardboard boxes, wood containers and plastic bags may cause the yellowing of clothing. These storage boxes emit gases and other by-products. Over time, these by-products can seep into clothing, causing yellow stains. Acid-free storage papers and containers are available for protecting white clothes in storage.