Outdoor sleeping bags are divided into down, hollow cotton, ordinary cotton, polar fleece, etc. by the warm layer material. We roughly divide them into down and cotton. Folding sleeping bags are just two ways of filling and rolling at will, but due to the characteristics of the material, their folding and storage methods are different. Let us discuss each method in detail below.
Down sleeping bag is an air warm layer formed by the expansion of down to achieve the purpose of heat preservation. It can be seen from the above structure introduction that no matter which folding method is used, the three-dimensional space in the sleeping bag is actually flat, so theoretically speaking, down sleeping bags can use any folding method. However, according to our actual experience, randomly filled sleeping bags have better compressibility than rolled up sleeping bags. In theory, the folding position of the randomly inserted sleeping bag is very random, and due to long-term repeated folding, some parts will not age. On the contrary, a tumbling sleeping bag will have relatively fixed creases, making it easier to age. However, you must not be too strict, because theoretically speaking, aging is nothing more than that. In actual use, the sleeping bag cannot be used because the zipper will be damaged or scratched due to the aging of the sleeping bag due to folding. In addition, when the down sleeping bag is not used for a long time, it should be stored in a bag twice the size of the original sleeping bag cover.
The hollow cotton sleeping bag is produced with the development of man-made fiber technology. In addition to keeping warm through enlarged fiber gaps, hollow fibers can also keep the interior warm. Therefore, it is superior to the down sleeping bag because it still has a certain warmth retention performance when wet, but its compressibility and weight are not as good as down materials, so it cannot completely replace down products. Similar to down sleeping bags, most hollow cotton sleeping bags also use a three-dimensional structure, so two folding methods can also be used. Here we do not recommend you which method is better, I believe you will gradually develop a fixed usage habit.