Before Four Treasures of the Study appeared, people first carved words on tortoise shells, which was Oracle Bone Inscriptions. Later, figures were cast on bronzes. This is a bronze inscription, or Zhong Dingwen. Pens appeared in the Spring and Autumn Period, and both knives and pens were used to engrave or write on bamboo slips and wooden slips. The earliest pen was called "Yu", which was dipped in paint to write. With a pen, there will soon be an inkstone for paint mixing. Meng Tian, the general guarding the Great Wall in Qin Dynasty, improved the pen in Cai Lun to make it an ordinary writing brush. Soon after the pen was improved, ink appeared. It is much more convenient to grind ink with an inkstone and write with a brush dipped in ink than to use pigments. But wooden slips and bamboo slips are too heavy, so people write on silk. During the Qin and Han dynasties, silk books and bamboo slips were used together. Although silk is light, it also has the disadvantage of high price, so people have been looking for something as light and cheap as silk to write. In the Western Han Dynasty, paper made of hemp appeared. This kind of hemp paper is rough and not suitable for writing. On the basis of using hemp to make paper, Cai Lun continued to carry out new experiments.
Cai Lun, whose name was Zhong Jing, was a eunuch from Liu Zhao to Liu Hu in the Eastern Han Dynasty. He was honest, dared to give advice to the emperor, and won the trust of Han and Emperor. Cai Lun is good at inventing. Seeing that bamboo slips used for writing are too heavy, silk is too expensive, and the existing hemp paper is not suitable for writing, he made up his mind to make a cheap and easy-to-write paper.
Cai Lunxian carefully studied the previous paper-making experience and learned that the original process of making hemp paper was to mash hemp fibers and press them into thin sheets. Because the process is simple, the paper made is very rough. Cai Lun thinks that if the craft is fine, the paper may be exquisite and easy to write. So he began to pound marijuana so hard that it was pressed into thin paper. This paper is more delicate, but it is not ideal, because there are still a lot of crude fibers in hemp that cannot be crushed, so the paper made is still not suitable for writing, and the cost of making paper with hemp that can weave linen is not cheap.
Cai Lun further believes that hemp can make paper because it has fibers, so rags, broken fishing nets, bark, hemp and other worthless things also contain fibers. Can it also be used to make paper? So he began to do experiments again. He collected rags, broken fishing nets, bark, hemp and other things, soaked them in water first, washed away the dirt, then pounded them into pulp in a stone mortar, and then pressed them into pieces to make paper. In this way, paper is produced by using worthless things as raw materials, and the cost is reduced. However, the previous shortcomings still exist. There are also some unbreakable fibers mixed in, and the paper made is not smooth enough, which is still not suitable for writing.
In order to smash the fiber worse and make the paper more delicate and smooth, Cai Lun added corrosive lime and other materials to the rags, broken fishing nets, bark, hemp and other raw materials used for papermaking, and put them together in a stone mortar for spring ramming. As a result, not only the raw materials were stirred worse, but also the bleaching effect unexpectedly appeared, which made the mashed pulp white. However, the paper directly pressed with this pulp can't remove the coarse fibers that can't be crushed, and because of lime and other things, there are many fine particles in the paper.
Cai Lun continued to do the experiment. He diluted the mashed pulp with water, put it in a big wooden trough, and then caught the thinner pulp floating on it with a thin curtain. After the thin curtain forms a thin and uniform layer of pulp, it is dried and removed, and it becomes a white and delicate paper. In this way, Cai Lun's experiment of improving papermaking was finally successful, and the paper convenient for writing was made. This is the first year of Emperor Xing of Han and Yuan Dynasties (A.D. 105).
Cai Lun played the role of Emperor Wu of the Han Dynasty in the process of improving papermaking. Han and Emperor were very happy and told Cai Lun to continue to improve, expand the scale of papermaking and produce more and better paper. Cai Lun lived up to the trust of Han and Emperor, and made more and better papers. Cai Lun was named Long Tinghou when he was in Emperor Han 'an, so people called the paper made by Cai Lun "Cai Hou Paper".
Cai Lun's experiment of improving papermaking was successful. Later, people constantly improved and perfected it, making the paper more and more exquisite. The raw materials for papermaking are also expanded because of the different output in different places. For example, where rattan is produced, rattan bark is used as raw material for papermaking; Where bamboo is produced, it is used as a raw material for paper making; Where there are many trees, paper is made of paper bark; In coastal areas, seaweed is used to make paper.
With the progress of papermaking, the requirements for pens, inks and inkstones have also increased, which leads to a very close relationship between Four Treasures of the Study. With the improvement of papermaking, writing is easier, more and more people write books and articles, and culture develops more rapidly. The improvement of papermaking greatly promoted China's art of painting and calligraphy. Before the Eastern Han Dynasty, there were some painters and calligraphers in China. After the Eastern Han Dynasty, there were more successful painters and painters.
With the development of social productive forces, people's lives are getting richer and richer, and the uses of paper are gradually increasing. It is not only one of Four Treasures of the Study, but also used for packaging food and other items. In daily life, even people without culture can't live without paper.
Cai Lun's improved papermaking first spread to Korea in the East and then to Japan through Korea. About the Tang Dynasty, papermaking spread to Europe through the Western Regions. Papermaking, one of China's four great inventions, has finally spread all over the world and made great contributions to the development of world culture.