Common laundry chemicals include bleach, sodium salt, surfactants, and enzymes. These chemicals work together to remove stains from clothing and prevent them from redepositing on those fabrics while they are still undergoing the wash cycles. The stains, once they have been neutralized by the detergent, may then be carried away out of the washing machine with the dirty water.
Bleach is a basic ingredient in laundry chemicals used to remove stains. The two types of bleach that may be included in detergent are chlorine bleach and oxygen activated bleach. Chlorine bleach tends to be harsh on fabrics and stains, and will remove color from anything it comes in contact with. This type of bleach is often added to laundry loads of white only clothing separately from the detergent to boost its stain removal capabilities. Clothing that contains color is generally manufactured in such a way as to protect the dye colors from oxygen activated bleach, which does not contain chlorine. This type of bleach only interacts, through an oxidizing process, with the non-protected stain molecules to neutralize their colors.
Many detergents also contain water neutralizers, such as sodium salt. Hard water is characterized by large amounts of calcium and magnesium, among other minerals, and can prevent soap from lathering. Sodium salt, when added to laundry chemicals, prevents the soap from solidifying when it comes in contact with hard water and allows it to remove stains on clothing. It also holds the excess dirt in the water so that it does not redeposit on fabric during the wash cycle.
Surfactants are one of the most important ingredients used in laundry chemicals that help penetrate and remove stains from fabrics. These chemical compounds affect the surface tension of a liquid, allowing it to penetrate other liquids or solids. In detergent, it can act as a wetting agent that lifts foreign stains out of clothing fibers and suspends it in the surrounding wash water. Together with the chemical neutralizers, the soils and stains are then drained out of the washing machine with the used water and do not reappear on any part of the cleaned clothing.
Laundry chemicals also include a variety of enzymes that break down proteins so that they may be lifted easily away from the fibers of the clothing. The stains that commonly appear on clothing and fabric are generally made of such proteins. Protease is one type of enzyme found in many detergents that breaks down the proteins that comprise organic stains. These often include grass, dirt, and the soil lines that appear when clothing rubs against skin repeatedly, such as near the neck and sleeves of shirts.