When did Gleditsia sinensis come into being in history?

In the Song Dynasty, a synthetic detergent appeared, which was made by mashing and grinding natural Gleditsia sinensis (also known as Gleditsia sinensis, hanging knife and Gleditsia sinensis) and adding spices to make an orange-sized ball for washing face and bathing, commonly known as "soap ball". Song people carefully recorded in Old Wulin, Volume 6, Little Broker, that there were already merchants specializing in "Soap Troupe" in Lin 'an, Kyoto in the Southern Song Dynasty. In the Compendium of Materia Medica written by Li Shizhen in the Ming Dynasty, the production method of Gleditsia sinensis was recorded: "Gleditsia sinensis grows in high mountains, with tall trees, leaves such as sandalwood and Gleditsia sinensis, which bloom in May and June, bear three or four inches of pods, are plump and fleshy, contain several sunspots, are as big as fingers, are not round, and are edible. Picking pods in October, boiling and mashing, white flour fragrant pills, bathing the body, removing dirt and moistening, is better than Gleditsia sinensis. In addition to natural Gleditsia sinensis, plants such as Sapindus mukoraiensis have also spread among the people and become good cleaners. There is such a record in County Records of Taiwan Province Province: "Yellow-eyed trees are disease-free trees. When I was in senior two and senior three, it was really like loquat, with yellow color and wrinkled skin. It is used to wash clothes, and pulp is like soap. ",its peel will produce foam after rubbing with water, and people in Taiwan Province Province have used it for laundry for at least several hundred years. Because it contains yellow pigment, clothes should be carefully dyed yellow after washing for a long time. According to legend, washing your hair in this way can always keep your hair black and shiny, and it also has the effect of cleaning and moisturizing.

In the west, it may be traced back to an ancient Greek island called Lesbos 4,000 years ago. The local people sacrificed animals to heaven. Because wood is used when burning animals, the mixture of wood ashes and animal fat will produce a soapy yellow substance. The heavy rain washed these things into the river where local women often washed their clothes. They found that their clothes were cleaner. Although traces of using similar soap can be found from ancient Greece, a poetess named Sappho recorded these stories in history. In memory of her, people later called this process saponification, and the chemical name was soap making. In addition, in 3000 BC, Mesopotamia found that the alkaline substances in the ashes after burning plants had detergency after mixing with oil, which was also one of the sources of soap. However, Gauls should be the first to try to make soap and succeed. At that time, they called soap "sapo". At that time, soap was an ointment-like substance containing animal fat and plant ashes. When the method of making Sapo was gradually introduced to the Mediterranean, Arabs improved Sapo into hard soap made of olive oil and soda. At this time, soap began to be produced in large quantities. Soap was really widely used in18th century and19th century. At the end of 18, after the advent of the industrial revolution industry, a large amount of cheap sodium carbonate was obtained, which promoted the new development of the soap industry. But in the middle of the 20th century, the development of synthetic chemistry and petrochemical industry provided cheap chemical raw materials for detergents, promoted the rise of synthetic detergents and greatly changed the development of soap industry. However, handmade soap, which has been neglected in recent years, has risen again. Because of its natural and unique properties, handmade soap is easily biodegradable and decomposed by microorganisms in the process of sewage treatment, so it will not cause pollution problems in rivers, lakes and waterways.