An important index to evaluate the thermal performance of materials is the thermal conductivity.when the material’sthermal conductivity data smaller, the heat transfer will become slower,the material will be warmer.Still air is the best warm material,it’s Thermal conductivity is only one third of cotton,Keep warmer than any piece of clothing on your body, of course it must be still air,So that he will not convection and take away the heat.Like the heat insulation materials commonly used in northern construction materials, they use still air to insulate heat.But you could not wear only still air in the civilized society.Silk, wool, and cotton are all top natural quality to keep warn materials.But down is the most outstanding one, none of them, thanks to his special structure.
The feathers of ducks have positive feathers, slender feathers, which are also called feathers. Down feathers are also called downs, and downs are the key to keeping the down warm.There is a very small velvet core in the center of the downs, which connects dozens of velvet branches, and each velvet branch grows a large number of velvet twigs. Through the microscope, you can see that there are many triangles and forks on these velvet twigs. There are a large number of gaps and cavities inside these fibers. These structures can store a large amount of still air in the pile and reduce heat conduction. On the other hand, the pile has a large amount of still air. A small amount of electric charge repels and separates each other, thereby forming radial fluffy flowers, countless fluffy flowers, velvet branches, and velvet twigs overlap together to form a dense fiber network that can make the air static and reduce heat convection. Therefore, the essence of down happens to be a still air reservoir, which can fix as much air as possible with a limited volume and mass, so that you can feel warm in the cold winter.
A qualified down jacket need to check the amount of down filling and the down content.The amount of down filling refers to how many weight down in one jacket. Generally speaking, the higher weight amount of down filling, the jacket will be warmer , but this is not absolute,There is a maximum value for the air volume that can be stored in down. If the density of the filled down fibers is too high, it will reduce the amount of air storage, and the heat will pass through more easily.And the higher amount of down, the heavier the down jacket. If you don’t go to extreme cold places, generally choose a down jacket with a down amount of about 100-200g. Compared to the amount of down, the down quality is more important.The higher quality of the down, the warmer the down jacket.The down jacket has at least 50% down content. If the down content quality is low, the filling may have a lot of miscellaneous hairs, impurities, or crushed cashmere processed by crushing wool pieces.Regardless of their poor thermal performance, their elasticity is also poor, and some high-end down jackets will also be marked with bulkiness. It refers to the volume that a unit mass of down can fill.Under the same quality, the greater bulkiness, the more air the down can store, and the better the warmth retention performanceThe higher the bulkiness, it means that there is no need to fill too much down. Down jacket can be warm and light.The bulkiness of a medium-quality down jacket is generally 400-500in3/oz, which is enough for your daily warmth, but the down jacket you buy often does not indicate the size of the bulkiness.At this time, you can feel the elasticity of the down by pressing, the faster rebound, the better the bulkiness
As for fillings, there are mainly these categories: white goose down, gray goose down, white duck down, gray duck down, goose and duck mixed down, ducks and geese, ducks have a short growth cycle and high slaughter.Therefore, 90% of the down in China is duck down, and the price is relatively cheap. The production cycle of geese is long, the number of breeding is small, and the down core of the down in the goose down is smaller, the down is bigger, and the fluffy is high.Warmth retention is relatively better, and the price of goose down is twice that of duck down. However, studies have shown that the heat preservation rate of the same volume of goose down and duck down differs by about 5%, but the price of down jackets made by the two is several times different.
In addition, the color of down also affects the price. Gray down will show a light-colored down fabric, which affects the look and feel. It is generally used in dark down jackets, and the price is relatively cheap.
Finally, you also need to look at the warp and weft density ofthe down jacket fabric. If the density is not enough or the sewing process is not good, the fine down will pass through the needle eye, reveal the down and stick to your sweater.
So if you choose a light but well down proof fabric jacket fabric, then please contact a professional down jacket fabric company-HUIMIN TEXTILE to give you a professional answer