Drake wearing Canada Goose down jacket
For centuries, humans across the globe have used down feathers for insulation. The down feathers of various species of wildfowl, gulls and other seabirds have historically been used for insulation, most now come from domestic geese. Some 70 percent of the world's supply comes from China, typically from birds killed for their meat. Most of the rest comes from Europe and Canada, from birds harvested for meat or pâté.
In the United States, Federal Trade Commission regulations require that any product labeled "100% Down" must contain only down feathers, while products labeled simply "Down" can contain a mixture of fiber and feathers. In addition, products labeled as "Goose Down" must contain at least 90% goose feathers. Down insulation is rated by fill power, which is the number of cubic inches displaced by a given ounce of down (in3/oz). To measure fill power, an ounce of down is placed into a graduated cylinder, and a small weight is dropped in on top of it; the volume below the weight indicates the fill power. Eider down has the highest fill power, at 1200. However, even down with a fill power as low as 550 still provides reasonably good insulation. Higher fill-power downs will thus insulate better than lower fill-power downs of the same weight. Insulation in most outdoor equipment ranges from about 400 to 900 in3/oz (230–520 cm3/g). Down rated 500-650 in3/oz (290–375 cm3/g) is warm enough and light enough for most conditions, and 800-900 in3/oz (460–520 cm3/g) fill is used for very lightweight and/or very cold-weather gear.
Down is warm, lightweight and packable. If well cared for, it retains its loft up to three times longer than do most synthetics. However, when it is wet, the thermal properties of down are virtually eliminated. Down forms clumps if exposed to dampness or moisture, and will mildew if left damp. In addition, it will absorb and retain odors.
Down feathers tend to become more allergenic as they age, as they become contaminated with molds and dust mites. Pillows provide the most common source of exposure, though mattresses, comforters, outerwear and upholstery can also cause problems. A Finnish study has shown that true feather allergies are rare, with most issues caused by dust mites.
Types of Down
Goose down: The down clusters harvested from geese are larger and possess more loft than down from many other birds. Hungarian goose down: Widely considered to be the finest quality down clusters, they are larger than the norm and are mostly pure white in color.
Duck down: The clusters of down harvested from ducks are smaller and more coarse than those of geese. Duck down is usually collected from ducks raised for food, so they're slaughtered at a young age and the down is not fully mature. Duck down is considered low quality and is sometimes mixed with goose down.
Eider down: This is considered to be the ultimate in duck down; it's collected from the breast feathers of the female eider duck and has the largest duck down clusters.
Feather-down combinations: Down compacts with age and is not appropriate for some applications; most down-filled pillow forms are stuffed with a combination of down and feathers. The presence of feathers adds weight, stability and bulk. Therefore, a mixture with more down will be lighter and fluffier than a pillow with a higher feather ratio.
編排整理 Edited: ACOTEX Fabric Talks 布料指南