Stabilizing fragrance in fabric softeners with fermentation-derived cellulose


Senior Technical Support & Development Manager, CP Kelco, Leatherhead, United Kingdom
Principal Scientist, Application Development, CP Kelco, Atlanta, Georgia, USA
Director, Strategic Segment, Marketing, CP Kelco, Paris, France


Globally, consumers are washing millions of loads of laundry every year – and relying on liquid fabric softener to not only combat wrinkles and static cling but add fragrance as well. Many fabric softeners today rely on cationic surfactants to bind by electrostatic attraction to the negatively charged groups on fabric fibres and smooth them, effectively lowering friction. Liquid fabric softener also delivers fragrance; but as it drains with the rinse cycle, it takes some fragrance benefits along with it. Some formulations are also not biodegradable, or they may not break down before reaching waterways and potentially harm the ecosystem (1). Any way to maximize biodegradability and minimize loss while still delivering softening and scent performance will significantly drive this market segment and help reduce aquatic pollution.
In this article, we will assess new cationic-compatible and readily biodegradable, fermentation-derived cellulose technology in the form of CELLULON® RC-76 Cellulose Liquid to stabilize biodegradable, encapsulated fragrance in liquid fabric softeners, and the effect of that stability on fragrance perception.

Almost a century ago, fabric softeners were introduced (2) to combat the mechanical stresses and friction of machine washing that result in fraying, pilling, stretching, wrinkling, roughness and static cling. Chemists understood that using a product to coat the surface of the fabric could help reduce friction and provide a softer texture. To this day, many fabric softeners contain cationic surfactants to attract the anionic fabric fibres and effectively neutralise the charge.


The most common type of fabric softener is a liquid that is added to the wash during the rinse cycle and uses a cationic quaternary ammonium compound, commonly referred to as an esterquat. These esterquat softeners must be added separately to the laundry detergent to prevent precipitation with the anionic surfactants that detergents commonly use.


In addition to fabric care, scent – as a sign of freshness and elimination of malodors – is a major part of the laundry experience (3). As you can see in Figures 1 and 2, the fabric freshening segment is a growing group even as overall fabric softener product launches and sales w ...