The warmest, lightest jackets and sleeping bags all have one thing in common: down insulation. Down, the soft underlayer of a goose’s or duck’s feathers, traps body heat when it’s dry, but flattens into a soggy mass when it’s wet. This year, three companies developed methods of waterproofing the feathers without losing loft.
Down Decor, based in Ohio, provides the fill for the Brooks-Range Mojave, one of the first jackets to feature the treated feathers. Down Decor mists the down with a layer of perfluoroalkyl acrylate, a hydrophobic polymer that forces water to bead up. The company says its insulation absorbs one quarter of the moisture of untreated down and dries five times as quickly.
Care: Machine wash
To measure the water resistance of Down Decor’s insulation, we set up a side-by-side test against untreated down. We poured a half cup of water into jars with a quarter cup of fill and left both samples to sit for five minutes. We then removed the fill and timed how long it took each sample to dry naturally.
When removed, the Down Decor fill retained only a couple of drops of water; the untreated down held on to about 5 milliliters. The Down Decor fill dried within an hour and lost none of its loft, while the sticky, wet blob of untreated down took a full weekend to dry completely.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.