Dealing with Yellowing (Yellow Discoloration) of White Clothes: Identifying the Cause and Know-How for Effective Removal Using Sodium Percarbonate

💡 The Enemy of White Clothes! Dealing with Yellowing (Yellow Discoloration): Identifying the Cause and Know-How for Effective Removal Using Sodium Percarbonate

The phenomenon of clean white clothes or white underwear suddenly turning yellow (yellowing) is a common laundry concern. Yellowing mainly occurs when organic materials such as sweat, sebum, and detergent residue remaining on the clothes oxidize during long-term storage. We share the know-how to accurately identify the cause of yellowing and effectively remove it using sodium percarbonate, etc.

🔑 Core of Yellowing Removal: Removing Oxidized Stains, Appropriate Temperature, Sufficient Soaking Time

The key is to dissolve the oxidized organic matter that caused the yellowing, utilize warm water (above 40°C) which is optimal for stain removal, and oxygen-based bleach (sodium percarbonate), and secure sufficient soaking time.

💡 3 Steps for Yellowing Removal and Prevention

1. 🧪 Identifying the Cause of Yellowing and Selecting the Remover:

Cause of Yellowing: The most common cause is sweat or sebum that was not completely removed during washing oxidizing when combined with oxygen in the air.
Remover: Chlorine bleach (e.g., Clorox) is strong but can damage fibers and make stains yellower. Therefore, using sodium percarbonate (oxygen-based bleach) is safer and more effective.

2. ♨️ Yellowing Removal Using Sodium Percarbonate:

Supplies: Yellowed clothes, basin, sodium percarbonate, hot water (50~60°C). (Water that is too hot may damage fibers)
Soaking Process: Pour warm water into the basin and dissolve about 1/2 to 1 paper cup of sodium percarbonate. Place the yellowed clothes in and soak for 1 hour up to a maximum of 4 hours. (Adjust time according to the degree of yellowing)
Rinsing and Final Wash: After confirming the yellowing has been removed, rinse several times with clean water to completely remove residue, and perform general washing once more.

3. ☀️ Storage Know-How for Yellowing Prevention:

Perfect Washing is Essential: Always wash cleanly before storing to prevent residual sweat and sebum components, which cause yellowing.
Remove Bleach/Detergent Residue: Rinse thoroughly several times after washing to ensure no detergent or bleach components remain on the clothes.
Storage Environment: When storing, keep in a dry and well-ventilated place. Use a non-woven fabric cover instead of plastic, and include a dehumidifier in the closet.

Even if white clothes do not appear sweaty, unseen organic matter may remain. Be sure to wash them with extra care before storing.