What's Inside — Downy Coats Briefs With Horse Fat

Patrick Di Justo

* Photo: Tim Morris * Dihydrogenated tallow dimethyl ammonium chlorideA derivative of rendered fat from cattle, sheep, and horses. Just boil it down and mix with ammonium (NH4). After a series of chemical pit stops, out comes a quaternary ammonium compound, or quat—a positive ion in which the hydrogen is replaced by long-chain organic molecules. Quats effectively coat your clothing with lipids, making the fibers soft to the touch. These fats also make fabric a bit less absorbent—don't use on towels or cloth diapers—and the positive charge neutralizes static electricity. There are a few other quats in Downy, with easily pronounceable names like 1-methyl-1-tallowamidoethyl-2 -tallowimidazolinium methylsulfate.

Calcium chlorideThese water-absorbing crystals are in everything from road deicers to food additives. On a molecular level, quats tend to clump into fatty globules. CaCl draws water out of them by osmosis, keeping the goo flowing smoothly.

PEG 8000The 8000 is this polyethylene glycol's molecular weight; in this formulation, each molecule weighs as much as a small protein. Here it's an emulsifier, keeping the fats and other liquids from separating on the shelf.

Kathon CGAlso known by the catchy moniker 5-chloro-2-methyl-3-isothiazolone. So much animal fat in one place serves as a perfect medium for microbes. Without powerful antimicrobials like isothiazolones, April Fresh would quickly turn into August Rancid.

PerfumeThe sizzle that sells the steak: Research shows that scent—locked into the clothing fibers by the fatty coating—is the main reason consumers choose one detergent or fabric softener over another.

Ethanol and isopropanolDowny is shipped year round and isn't always stored at room temperature. If the quat cocktail were to drop below freezing, it would thicken and need to be dissolved in water. Alcohols act as antifreeze to keep things from solidifying into a pitcher of lard.

Deionized waterThis is added as a preservative for the various quats in the bottle. It also eliminates any ferric ions (dissolved iron) present in your laundry water, which can yellow some fabrics.

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