Perspiration is made mostly of water, but it does contain trace amounts of minerals, lactic acid, and urea. The content makeup varies from person to person, but it, along with the materials found in anti-perspirants, in conjunction with a concentrated area (like the underarm area of shirts) leads to build up over time and with age and the heat of finishing after cleaning, causes these materials to oxidize and turn the stain yellow.
What can you do to reduce the effects? Below are some suggestions.
- Let your anti-perspiration or deodorant dry completely before dressing.
- Wash or dry clean clothing as soon as possible after wearing; the quicker you address dirty garments, the more likely stains and spills can be removed.
- Consider wearing underarm shields with your dress clothes.
- Switch from anti-perspirant, which contains aluminum chlorohydrate that tends to clump in cotton and damage garments fibers, to deodorant.
- Try soaking clothing in cold water and dish soap, which contains de-greasers, immediately after wearing.
- Finally, occasionally soak in a mild color-safe bleach. Avoid using chlorine bleach as it will cause the optical brighteners to breakdown.