Why did most Song emperors wear red robes?

At present, in our China people's cognition, the emperor is the son of heaven, and we are all descendants of the dragon. Therefore, the clothes of ancient emperors were all covered with dragons, and one of the colors of the clothes must be yellow. This is basically a deep-rooted idea of everyone. If they suddenly wear other colors, we will feel particularly strange. Then someone was curious. Why did they wear red robes instead of yellow in the Song Dynasty? Why is this? Is there anything special?

In fact, at the beginning, the color of the robe was not yellow or red, but black. After Qin Shihuang unified the world, the robes he wore were black, not only what he wore, but also the color of the military flag. Of course, it is not that he has any obsession with this color. It was only because a dyeing technology in the Qin Dynasty was not very developed at that time that it was said that no matter whose clothes were, they tended to be dark, and among these colors, only cyan was a little more advanced, so before the Zhou Dynasty, the emperor's clothes were all cyan.

Black dye didn't appear until the Warring States period. Black is more serious and solemn than cyan, and it lasts longer, so Qin Shihuang chose this color. Later, in the period of Emperor Wen of Han Dynasty, dyeing technology began to develop and mature slowly. At this time, people will try many kinds of fresh colors, and they will dye their clothes yellow on a large scale. It was found that yellow was more durable and beautiful than black. In addition, according to some previous statements, Emperor Wendi decided to change the dragon robe of a different color to yellow, and he became the first emperor to wear yellow dragon robe in history.

In the Song Dynasty, the dyeing technology improved again, and red appeared again, which became popular and became people's favorite color. People have been wearing red robes since Zhao Kuangyi.