Soak in sodium percarbonate (oxygen bleach)

Dissolve 2-3 tablespoons of sodium percarbonate per liter of hot water (50-60°C) and soak yellowed cotton or linen for 1-6 hours. For heavily yellowed items, soak up to 12-24 hours, stirring occasionally. Wash normally afterward.

Why It Works

Sodium percarbonate breaks down into hydrogen peroxide and washing soda in water. The hydrogen peroxide releases active oxygen that oxidizes the chromophores causing yellowing, while the alkaline washing soda boosts the reaction. Unlike chlorine bleach, it does not attack cellulose fibers.

Tips

• Water must be above 50°C for full activation
• Safe for both cotton and linen at recommended concentrations
• Pure sodium percarbonate is available in bulk and is more economical than branded products
• Rinse thoroughly after soaking to remove all residue