PureInsight | January 13, 2003
[PureInsight.org] The character-setting printing process is recorded in Mengxi Bitan as one of the four great inventions of ancient China. This invention appeared in China 400 years earlier than in the west. This is what is recorded in the book on character-setting printing:
Bi Sheng, a commoner during the North Song Dynasty (960-1127), invented character-setting printing. He used clay to imprint stamp seals, one seal for each character, and then fired the seals to make them hard. He suggested that before setting the characters, one should prepare an iron plate by spreading adhesives mixed by resin, wax, and the "dust of paper" on the plate. Then he affixed an iron frame to the plate before placing the specific character seals. When the seals were fully arranged on the iron plate, the plate was heated until the adhesives began to melt. A wooden board was then placed on top of the seals to make the surface of the seals flat and smooth, thereby adhering the wooden board to the iron plate. It could then be used to print. This manufacturing process is time-consuming if one wants to print two or three copies. However, it is extremely efficient if you want to print hundreds or thousands of copies.
As a rule, you should prepare two iron plates. While one is being used for the current print job, the second one can be assembled for the next. With the two used in turn, printing will be finished very fast. There are several seals for one character. There are more than twenty seals for the frequently-used characters because some characters can appear repeatedly in one printing. Seals are as thick as coins. When the seals are laid aside, they will be wrapped with paper, by order of phonetic rhyme, and kept in a sectioned wooden container. If an unprepared character is needed, it will be carved onto a seal upon demand, and fired by burning grass. It will take no time to do this. The way to remove the seal is to heat the printing plate, melting down the adhesives, and then taking them off. The seal won't be smeared by the adhesives because it is made of clay.
We can see from the process of printing described above, that this technique is very simple to use and convenient to put into storage. It is also efficient to operate. This makes the invention of printing considered to be one of epoch-making inventions. This gives us a glimpse at one of the advanced technologies used in ancient Chinese culture.
Translated from: http://www.zhengjian.org/zj/articles/2002/12/15/19642.html