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Material science
Daunen Wärmeisolation

Why do down have very good heat-insulating properties?

The quilt and the filling themselves do not keep the body warm. The feathers and down make sure that the heat of the body does not disappear, i. e. they store the heat.
 
Down are significantly lighter than feathers. With the same weight they offer a much larger volume. Due to their three-dimensional structure like a flake down are able to store large amounts of air which is not a good heat conductor. The countless air-filled buffers make up the high capacity in terms of heat insulation.
The quilt and the filling themselves do not keep the body warm. The feathers and down make sure that the heat of the body does not disappear, i. e. they store the heat.
 
Down are significantly lighter than feathers. With the same weight they offer a much larger volume. Due to their three-dimensional structure like a flake down are able to store large amounts of air which is not a good heat conductor. The countless air-filled buffers make up the high capacity in terms of heat insulation.
In contrast to the feather, the down is multi-dimensional. Due to its three-dimensional structure and the ability to continuously recover its original shape, a down traps large amounts of air in proportion to its weight.
 
Air is not a good heat conductor. This property works for instance with double glazed windows and cavity bricks to the effect that air forms a protective buffer from cold.
 
A good down filling contains about 2 millions of interweaved and fluffy barbs. Hence, a layer of air is formed which is a poor heat conductor and protects from cold. Due to their resiliency down can be crushed or compressed. If they are thoroughly fluffed up, they will quickly recover their old shape.
 
Daunen Decken

Why are duvets filled with eiderduck down so expensive?

Especially eiderduck down are of high quality. They come from the species eiderduck that are living as protected birds in the wild on the coasts of the Northern Seas. Eiderduck down must be picked from the abandoned nests after the breeding period.
Especially eiderduck down are of high quality. They come from the species eiderduck that are living as protected birds in the wild on the coasts of the Northern Seas. Eiderduck down must be picked from the abandoned nests after the breeding period.
They provide excellent fill power figures which almost double the fill power values of top-quality goose down. One kilogramme contains about 500 000 single eiderdown but only 300 000 goose down. Eiderduck down are even more delicate and lighter than goose or duck down and have a natural brownish colour. They have scarcity value and are difficult to process, respectively, which leads to stiff prices.
 
Eiderducks mainly live in Iceland, Greenland, Scandinavia and the Northern regions of Canada. They breed in hollows on the ground or on rocks and pad out the nests with down they plucked out from their bodies themselves.
Eiderducks are protected birds since they are a critically endangered bird species and cannot be bred.
 
After the young birds left the nest the eiderdown are collected. Only personnel that was well technically trained, is permitted to climb on the rocks to pick the down from the nests after the breeding period. Thus, there is tight supply, but great demand (Saudi-Arabia, Japan).

Eiderduck down have excellent heat-insulating capacities. The barbules are larger than goose and duck down and have countless ramifications. In spite of their size they are even lighter and more delicate than usual goose or duck down. The barbules of eiderduck down are twinned. Their barbs are frizzed and form prongs at their ends which make the down stick together. If they did not form a cohesive pad, the wind would blow the single down out of the nest.
 
The sticky structure of the eiderduck down makes the processing difficult. Bedding articles filled with eiderdown have to be cleaned and processed manually.

 


Further information on the internet:

 

Federn Daunen Herkunft

Why are most down and feathers imported?

Down and feathers are a by-product of meat production. Consequently, their production depends strongly on the nutritional habits of the respective country. A high consumption of geese and duck meat means a large amount of down and feathers. This is the case in most Asian countries where poultry meat plays a dominant role in the diet.
 
Down and feathers are a by-product of meat production. Consequently, their production depends strongly on the nutritional habits of the respective country. A high consumption of geese and duck meat means a large amount of down and feathers. This is the case in most Asian countries where poultry meat plays a dominant role in the diet.
 
Wärmeisolation Austausch

Suddenly the duvet does not keep the body warm any longer. Why?

Since down and feathers are natural materials they undergo a certain natural ageing process. In the course of time the filling gradually desiccates and you will find an increasing number of broken and damaged down and feathers. You can slow down the process by proper care (fluff up the duvet or pillow every day and air them regularly), but you cannot stop it.
 
If your duvet is not worn out, you should have it cleaned to remove residue such as sweat.
Since down and feathers are natural materials they undergo a certain natural ageing process. In the course of time the filling gradually desiccates and you will find an increasing number of broken and damaged down and feathers. You can slow down the process by proper care (fluff up the duvet or pillow every day and air them regularly), but you cannot stop it.
 
If your duvet is not worn out, you should have it cleaned to remove residue such as sweat. Besides, worn out filling components, in particular broken down and feathers are picked out and replaced by new material.
 
If your duvet has been used for a very long time, it will hardly be worthwhile to have it cleaned. You should rather consider to purchase a new one.
It is generally advised to replace a pillow after 5 years of use at the latest. You should purchase a new duvet after 8 to 10 years.

Further information at :

Füllung

What do the terms „waterfowl“ / „landfowl“ stand for?

In a wider sense, waterfowls are bird species whose habitat is especially contingent on waters. In relation to bedding products, only ducks or geese are regarded as “waterfowl”. Only their plumage is suitable as filling material for bedding products.
 
In the area of bedding products, especially chicken and turkeys are understood as landfowl (also “pawing poultry”). Their feathers – they do not posses any down – are not suitable for bedding products due to their small filling power.
 
In a wider sense, waterfowls are bird species whose habitat is especially contingent on waters. In relation to bedding products, only ducks or geese are regarded as “waterfowl”. Only their plumage is suitable as filling material for bedding products.
 
In the area of bedding products, especially chicken and turkeys are understood as landfowl (also “pawing poultry”). Their feathers – they do not posses any down – are not suitable for bedding products due to their small filling power.
 
Füllung

What is meant by fill power?

Fill power has nothing to do with filling weight. It defines the bulking capacity which means the ability to expand back to the original volume after having been exposed to pressure.
Fill power has nothing to do with filling weight. It defines the bulking capacity which means the ability to expand back to the original volume after having been exposed to pressure.
 
Down and feathers can be strongly compressed which means that they have a very small volume under pressure. When the pressure – for example through the weight of a human body – stops, they will quickly recover their old shape. One can crush them countless times and they will always recover their old shape, since they are very resilient. Thereby they constantly form air-filled pockets which ensure the heat- insulating effect.
 
There are different procedures for the measurement of the fill power:
 
The exact requirements for the measurement of the fill power are defined in the European standard EN 12130.
 
According to that, fill power is specified as “height of the volume occupied by filling material subjected to a specific pressure, expressed in millimetres”. (EN 12130).
 
The feathers and down are filled into a measuring cylinder and at first loosened by air which is blown in during a fixed period. Afterwards, a pressing plate and a measuring stick are set into the cylinder. The pressing plate compresses the feathers/down and moves downward. After a fixed period of time one can read off at which figure the pressing plate has stopped. This height (in millimetres) is read off at the measuring stick. Fill power is therefore expressed in millimetres.
 
This testing method is an important precondition for the producer to evaluate the quality of feathers and down.
 
This testing method is an important precondition for the producer to evaluate the quality of feathers and down. Fill power is the necessary prerequisite for “warmth without weight”. Therefore, a high fill power of bedding products is an especially important quality feature.
 
  Further information at DOWNAPEDIA:
Füllung

What is meant by “poultry“?

Poultry characterises “those bird species which are kept as livestock as well as pets (domestic poultry) […]”
(translated from: Brockhaus Studienausgabe, 2001, 20., revised and updated edition, volume 8, p. 230).
 
Poultry characterises “those bird species which are kept as livestock as well as pets (domestic poultry) […]”
(translated from: Brockhaus Studienausgabe, 2001, 20., revised and updated edition, volume 8, p. 230).
 
Federn Daunen

What is the difference between down and feathers

The structure and appearance of down and feathers are quite different. A down has a soft centre from which all the light fluffy filaments protrude. Feathers have a long and curved quill which makes them resilient in a way, at the same time providing them with the ability to expand back to their original shape after having been exposed to pressure. Thus, in contrast to down feathers are perfectly suited as filling material for pillows as they softly cushion the head at the same time supporting the neck as desired.

The structure and appearance of down and feathers are quite different. A down has a soft centre from which all the light fluffy filaments protrude. Feathers have a long and curved quill which makes them resilient in a way, at the same time providing them with the ability to expand back to their original shape after having been exposed to pressure. Thus, in contrast to down feathers are perfectly suited as filling material for pillows as they softly cushion the head at the same time supporting the neck as desired.

On the other hand, down are used as filling material for down duvets ensuring opti-mum thermal insulation and rapid decrease in humidity (climate of the bed hollow). Thereby, down are pleasantly light and very resilient.


However, there is one important thing to consider: Duvets and pillows should be fluffed up in the morning to retain their shape for a long time

 
Daunen

What are down?

A down has a delicate shape like a flake. It consists of an almost invisible down core with down barbs soft as silk and endowed with delicate ramifications growing radiantly from the core. Down is a highly resilient material. For instance, if you compress a fistful of down in your hand and unhand them, the down will quickly develop and recover their original shape.

A down has a delicate shape like a flake. It consists of an almost invisible down core with down barbs soft as silk and endowed with delicate ramifications growing radiantly from the core. Down is a highly resilient material. For instance, if you compress a fistful of down in your hand and unhand them, the down will quickly develop and recover their original shape.

 
Down are lighter than feathers. Due to their three-dimensional structure they can trap large amounts of air in between. This property is measured and figured in fill power (filling volume).
 
Air-filled pockets are formed between the fine barbules of the down which protect from cold. Due to their capacity of providing “warmth without weight”, down are extremely suited for top-quality bedding products.
From experience, one single down weighs about 0.0025 g to 0.0045 g. Down show differences depending on the breed and the weight of the geese and ducks.
 
About 250 000 to 400 000 single down are required to obtain one kilogramme of goose down.
To obtain one kilogramme of eiderduck down, which are the most delicate and at the same time the lightest down, approximately 500 000 to one million of single down must be collected.
 
Valid terms and definitions for feathers and down have been stipulated in a standard (EN 1885).
Federn

What are feathers?

Feathers form the main outer protection of the bird´s body. Feathers have a flat, two-dimensional shape with a continuous quill in the middle that is basically a shaft. Fine closely spaced feather barbules grow from the shaft. These barbules are also called vane.

Feathers form the main outer protection of the bird´s body. Feathers have a flat, two-dimensional shape with a continuous quill in the middle that is basically a shaft. Fine closely spaced feather barbules grow from the shaft. These barbules are also called vane.

Feathers are heavier than down.
 
The plumage of waterfowl is suited for the use as bedfeathers, more precisely the plumage of geese and ducks. Feathers deriving from waterfowl have a strongly curved quill (the shaft of the feather with fine barbules) ensuring that feathers do not lose their resilience over time. This property, which means the capacity to recover its original shape after having been compressed, forms the basis for heat insulation. If the quilt is aired, small air-filled pockets will be formed. Since air is a poor heat conductor, the countless hollows offer protection from cold.
 
The bedfeathers used as filling material for duvets and pillows almost exclusively originate from domestic ducks and geese. Eiderducks living in the wild are an exception, since their down (eiderdown) are collected from the nests after the young leave the nest.
 
Valid terms and definitions for down and feathers have been stipulated in a standard (EN 1885).
 
Excerpts from the standard (illustrations and definitions, for instance “down”, “goose feather”, “processed feather”) are available on www.edfa.eu -> Consumer information -> Glossary.