Down is an animal protein fiber and the best natural material for warmth retention. Its products are deeply loved by consumers because of their softness, fluffiness and superior thermal performance. The penetration rate of down products in many developed countries has reached 100%.
In the eyes of many people, down is pure and flawless, and other colors are inferior and fake.
The author once heard many merchants say: "After purchasing down products, customers found gray down under the fabric and immediately returned the products. The reason is that the products are inferior and dirty, and no explanation is helpful."
Are the feathers all white?
Down can be divided into white down and different-color down according to the color. Different-color down is down other than white down. There is no 100% pure white down in nature. If you want to achieve 100% pure white down, you can only do it artificially. Picking, the cost is very high.
Compared with white velvet, due to the limited use of gray, black, and yellowish velvet, the price is low. In order to increase its economic value and sell it at a good price, "bleached velvet" came into being.
Common velvet bleaching uses oxidant treatment and reducing agent treatment. Oxidative bleaching mainly uses H2O2 as the oxidant. The bleaching process requires a higher pH value, a higher water bath temperature and a longer oxidation time. This method is difficult to control, prone to over-oxidation or incomplete oxidation, resulting in brittle down, easy yellowing and serious color change after bleaching. The oxidized down is strongly acidic, and the use of this kind of down by consumers will cause certain harm to the body.
The reducing agent mainly plays a role in chemical setting of down and down, rather than decolorization and bleaching.
Down that has been bleached with chemicals feels hard, brittle, and has low bulkiness. The down content will drop significantly in the next year, and the quality will be greatly reduced. Strongly acidic sewage after bleaching contains a large amount of metal ions, even if it is discharged after treatment, it will pollute the environment.
It is difficult for natural things to be perfect. Different-color velvet is not an impurity or dirt, and has no effect on the quality. The national standard stipulates that the content of different-color velvet should be within 1%. Consumers love down because it is a natural protein fiber, which is light and has excellent thermal performance. However, some consumers pay more attention to the aesthetics of down and cannot bear a little bit of flaws in different-colored down, which is a bit of a waste. Blindly pursuing pure white down, you may end up using "bleached down"!