October 16, 2006

Volume 84, Number 42

Web Exclusive

Cyclodextrins Could Enhance Paint

Sugar-based molecule to help walls stay clean and pleasant smelling

Marc S. Reisch

Ring-shaped sugar-based molecules that resemble short ice cream cones may soon enable paint makers to add a pleasant fragrance to wall paints. Such a fragrance could last three or more years after the paint has dried on the wall. Marlies Regiert, business and sales development manager at Wacker Specialties, says her company has already patented the use of the sugar-based cyclodextrin molecules to deliver fragrance incorporated into paint. And once the fragrance is gone, these same molecules would still be at work on the wall absorbing unpleasant odors for years to come.

Because of their unique cone shape, cyclodextrins can host guest molecules much like a cone holds a scoop of ice cream, Regiert says. Manufactured under anhydrous conditions, cyclodextrins release their active ingredients in the presence of moisture. As hydrophobic molecules, cyclodextrins can host oils and the fragrances in perfume.

Other firms have already taken advantage of the fragrance-yielding ability of cyclodextrins. About seven years ago, consumer products maker Procter & Gamble introduced a cyclodextrin-containing fabric spray called Febreze. When sprayed on a fabric, some of the cyclodextrins in the product release a pleasant fragrance. Other unfilled cyclodextrins in Febreze go to work absorbing odors (C&EN, March 1, 1999, page 25).

The consumer products giant has a number of patents protecting its use of cyclodextrins in laundry and fabric care. But Regiert says Wacker, which manufactures cyclodextrins, has patented other potential applications for the versatile molecules that it hopes to share with customers.

For instance, cyclodextrins could incorporate mildewcides, so that bathroom paints containing them would slowly release their active ingredients to keep painted surfaces mildew free. Cyclodextrins incorporating mosquito and insect repellants could keep rooms free of pests. Other cyclodextrins infused with tea tree oil might provide fragrance as well as antifungal and antibacterial properties, Regiert says.

Some home improvement uses are already a reality, Regiert says. The German adhesives maker Tesa incorporates cyclodextrins in wallpaper paste to provide a "fresh scent." Regiert expects other similar uses to come.

[Top of Page]