If there is no color change, the article can be safely bleached. Oxygen bleaches are available in both a dry and liquid form. All dry oxygen bleaches contain inorganic peroxygen compounds, such as sodium perborate tetrahydrate and sodium percarbonate. Liquid oxygen bleaches contain hydrogen peroxide, which supplies the oxidizing agent directly. The hydrogen peroxide reacts with the soil and organic materials in the wash to either decolorize or break them up.
Hot water accelerates the bleaching action.
As water temperature decreases below 130 degrees F, exposure time must be increased. Powdered oxygen bleaches also contain a builder, usually sodium carbonate, which provides additional alkalinity and allows the perborate to function more effectively as a bleach. Other ingredients, such as surfactants, brighteners, bluing agents and fragrance can be incorporated into both liquid and powdered formulations. Enzymes are used in powdered bleaches. Read and follow bleach package directions.