Question

What are optical brighteners?

Answer 1

1. White fabrics gradually lose their whiteness with use and age. They turn yellowish in colour.
2. Optical brightening agents are colourless dyes which attach themselves to the fabric and make them appear whiter or brighter by reflectillg light.
3. They are applied to the fabric through finishing or home laundering agents (e.g., Comfort).
4. This reflected light counteracts the effect of yellowness, thus making fabrics appear whiter and brighter than before.
5. There is no chemical action involved in the process so it has no harmful effect on fabrics. Too much bleaching may also make the white clothes yellower with time, and excessive scrubbing may cause the clothes to get damaged by producing excess lint.
6. To counteract the dullness and yellowness of fabrics which come with age, the use of optical brighteners (OBAs) is recommended.
7. They make the fabric appear brighter by reflecting light and whiter due to its properties. It does this without damaging the fabric, as against bleaching or scrubbing.