Chương trình học tiếng Anh của VOA: Special English Technology Report - Making Paper. Xin hãy vào http://www.youtube.com/user/VietSpecialEnglish để xem các bài kế tiếp.
This is the VOA Special English Technology Report.
The earliest process of making paper was done almost five thousand years ago in Egypt and the Nile Valley. In those days, paper was made from strips of the papyrus plant.
Modern papermaking began in China about two thousand years ago. This process produced paper from cloth, straw, wood or the bark of trees. The raw materials are struck over and over until they become loose. Then they are mixed with water.
After the water has been removed, the flat, thin form remaining is permitted to dry. This becomes a sheet of paper.
Large machines started to be used for making paper near the end of the sixteenth century. Today, papermaking is a big business. But it is still possible to make paper by hand, since the steps are the same as using big machines.
You should choose paper with small amounts of printing. Old envelopes are good for this reason. Colored paper also can be used, as well as small amounts of newspaper. Small pieces of rags or cloth can be added. These should be cut into pieces about five centimeters by five centimeters.
Everything is placed in a container, covered with water and brought to a boil. It is mixed for about two hours with some common chemicals and then allowed to cool. Then it is left until most of the water dries up. The substance left, called pulp, can be stored until you are ready to make paper.
When you are ready, the pulp is mixed with water again. Then the pulp is poured into a mold. The mold is made of small squares of wire that hold the shape and thickness of the paper. To help dry the paper, the mold lets the water flow through the small wire squares.
After several more drying steps, the paper is carefully lifted back from the mold. It is now strong enough to be touched.
The paper is smoothed and pressed to remove trapped air. You can use a common electric iron used for pressing clothes.
There are many other technologies for people making paper using small machines.
More information about making homemade paper can be found on the Internet. You can also order information on papermaking through the website enterpriseworks.org.