Sleeping-bags
Thermal isolate properties
The most important qualities of isolate filling are influenced by its quantity and construction of boxes. The qualities of filling are ability to take the maximum of capacity or height of box of sleeping-bag in imaginary cut its own. Isolate medium are feathers or synthetic fibres and air, which only form the space for air to engage. The ability to engage maximum of capacity is influenced by compressibility and stability of shape for the isolate filling. The ideal result is enough warm sleeping-bag with low weight and small capacity after packing up.
Isolate fillings
Feathers or synthetic filling?
Chief problem that annoy interested person who wants to buy a new sleeping-bag. A few years ago the synonym of thermal sleeping-bag was anysleeping-bag with feathers. The advantage of synthetic material has dominated recently.The feather has become more exclusive material for super sleeping-bagsfor the lowest temperature. Hollow fibres with spiral shape have some or more tube different shape. The fibres are manufacturing as fleece and then they cancombine together. Characteristics of quality are compressibility and stability of shape. For example inland producer Condor use fleece with very thin fabrics in the middle. It makes next fragmentation of isolate filling, which reach maximum of capacity after unpacking in shorter time. Most often the hollow fibres have business names like Hollofil, Quallofil, Euroloft, Terraloft, Ultraloft, Micraloft, Libeltex. The greatest world producer of these materials is company called DuPont.
How can synthetic filling captivate?
We wrong call every synthetic filling hollow fibre. Sleeping-bag with isolate filling from synthetic materials is right for universal using from spring till autumn and when I don’t wantto annoy with periodic care. Its chief advantage is reality that it almost doesn’t absorb moisture and so I can dry it easily and quickly. It can be also easily to wash in washing machine without danger devaluation of isolate properties. Synthetic fibres are solution for allergic too.
Micro-fibres against the hollow fibres exploit the air, which get stick on his surface and which is keptby microscopic structure of fleece. This forms the isolate effect. Fleeceof micro-fibres has high formative stability and minimal absorbability. The best-known micro-fibre has business name Thinsulate and they comes from transnational giant 3M.
Feather is proved competent natural material with excellent compressibility and very good formative’s stability. The most oftenused feathers come from goose. But there aren’t feathers like feathers. The qualityof feathers depends on quantity of dusty feathers and small feathers. The numbers 90/10, 80/20 or 70/30 declare proportion between dusty feathers and small feathers. The first case it is the highest quality mixture with 90% dusty feathers. It would not be practical of use only clean dusty feathers because thanks to elastic feathers it is possible to take the sleeping-bag in needed air capacity quickly after unpacking.
Next important qualitative information is so-called fullness. It expressesthe general elasticity and expansibility, so the ability of feathers to take maximum of capacity. This quantity is measured in laboratory and it is declared in cubic inches. Clean dusty feathers reach values from 950 till 1000 cuin, mixture 90/10 c. 650 cuin and 70/30 c. 500 cuin.
Waterproof and permeability
The outer fabric of sleeping-bag would prevent getting of moisture from surrounding in to the isolate filling. Sleeping-bag wouldhave enough of permeability, which let the moisture to passfreely out to the surface and to disperse in to the atmosphere. Average man perspires 0.75-1.5 litre perspiration in stream form by one night, which has to remove. Otherwise, inside the sleeping-bag the moisture is concentrating in to water. Most isolate filling can’t create such capacity for air like the dry one.
Is it good idea to ruminate still about feathers?
Definitely yes andthe most expensive synthetic isolate filling of the highest quality don’t align to dusty goose feathers. Chief disadvantage of feathers is its susceptibilityof moisture. Feathers relatively easily absorb moisture and it makes worse thermal isolate properties. The sleeping-bag is hardly and slowly dried.
Outer and inner fabric
Permeability is the chief requirement for inner material. Fabric would be so light as possible to make extensibility of the isolate filling as good as possible. Inner fabric would be except the permeable also comfortable for touch with the skin.Feathers’ filling taxes a pretension heavily for using of outer fabrics thanks to its sensibility of moisture. The fabrics must be enough dense too not to let feathers penetrate outside. The best materials for feathers’ sleeping-bag are Gore Dry Loft and Excel Dry. These materials are of high permeability, well waterproof and are absolutely windproof.
Very expended material is Pertex, which is used for feathers sleeping-bag and sleeping-bag with synthetic filling. The most current material is polyamide with various of waterproof finishings. For the cheaper sleeping-bags often used cotton as inner fabric. It is comfortable in touch but it is relatively heavy, large, easily soiling and it absorbs moisture quickly and it takes long time to make it dry.
Effect of using fabric?
If we are choosing sleeping-bag we wouldn’t be limited by question if feathers or synthetic. Quality outer and inner fibres are important too. Especially for feathers sleeping-bag the properties of all sleeping-bags depend onthe finish properties. The fabric must prevent the moisture to penetrate in to isolate filling. At the same time it must make unable the vapour to browse out.
Construction
Construction of boxes has influence for result properties of sleeping-bag. Their form,size and configuration are adapted to thermal interval for which is the sleeping-bag identified. The simplest sleeping-bag with synthetic filling has only one stitching stratum. The second possibility is so-called sandwich structure with two independent stratums. Sleeping-bags with shingle form boxes are using for lower temperatures. The strips are stitched to top of fabric on one side and to inner fibres on the other side. The boxes have to safe the equalization of feathers in sleeping-bag. The construction must exclude the connection between outer and inner fabrics. The most often construction type is “V”, more thermal sleeping-bag has type of construction “Z”.
What is it the limit of thermal comfort?
The most important data of sleeping-bag are thermal intervals for using. The lower limits of thermal comfort would interested me in the shop. Thermal comfort means if man who has on one’s strata clothes should sleep quietly all night shouldn’twake up with cold. The lowest data indicate extreme thermal limit, when man would survived the night without consequences on his health.