Through the experimental statistics, respectively, from the duvet drilled out more than 2mm of down, we came to the following conclusions. Down the duvet stitches out of 66%, while feather silk accounted for 26%, in addition to 6% of the wool, and 2% of the velvet. From this, it can be seen that the main components in the drilling velvet are velvet and feather filaments. This is because each duvet has a number of Geng down fibers, each of which is mutually exclusive, which is why the duvet is fluffy and keeps a lot of stationary air inside the duvet.
When the duvet is squeezed or rubbed, because of the high density of the duvet fabric, low breathability, still air from the seam pinhole overflow, when the down of the thin and pointed velvet silk, feather silk and with the air ran out, forming stitches.