Paper made of wood: from which it is made

Paper is consumed by people in huge quantities. One person per year accounts for one hundred and fifty kilograms. From what and how to make paper, read in the article.

Historical background

For a long time, in 105 BC, Tsai Lun -Imperial national from China, made paper from mulberry tree. He made a mixture of his wood, hemp, rags, added wood ash and all this was laid out on a sieve to dry. After that, the stone was polished by the dried mass.

The paper was made of wood, and the Chinese eunuchTsai Lun became the first author of her technology. So the Chinese think. But scientists have a different opinion. This is due to the fact that archeologists often find in the territory of China paper scraps, which date back to an earlier period.

Raw materials

Paper is made from wood pulp, othersfibers of plant origin: reeds, rice, straw, hemp, as well as rag waste, waste paper and other materials. To produce cellulose, wood of different tree species is used. Wood pulp can be obtained in several ways.

The most economical is mechanicalmethod. At the woodworking enterprise, the wood is crushed, the crumb is obtained. It is mixed with water. Paper made from cellulose, obtained in this way, is unstable, newspapers are produced from it. High quality paper is made from cellulose, which is obtained using a chemical method. For this, small chips are cut from the wooden beam. It is sorted by size. Then they are immersed in a solution with chemical preparations and boiled in a special machine. After that, it is filtered and washed, as a result of which excess impurities are removed. So it turns out paper raw materials, which is called wood pulp. It produces paper for magazines, books, brochures, wrapping materials of great strength.

Paper from sawdust by one's own hands

Sawdust of pine or spruce is filled with water andthey cook exactly one day. Caustic soda is added to the water. In the absence of such, you can use food soda. After cooking, the mixture is washed with water and wrung out. Then again, the sawdust is poured into a pot of water and put on fire. Once boiled, the pan is removed from the fire, its contents are ground with a mixer. It turns out a mushy mass of a homogeneous consistency.

While sawdust is cooked, a frame is made, put onpallet, gauze is stretched on it. The mass is poured onto the prepared frame and distributed evenly over the entire surface. Extra water will drain into the pan. But to quickly remove moisture, it should be dipped in absorbent napkins. Then the frame is turned over and the sheet obtained from the mass is easily separated from it.

The sheet must be covered on both sides with paper ornewspaper and put between boards, from above to press something heavy. Under this press, he must lie for about five minutes. After that, the sheet is carefully placed on the foil and dried in the sun, in the oven, near the battery.

Composition

Paper made of wood is made on the basis ofWood pulp obtained using a mechanical method of production. Sometimes other materials are used as a basis. Such a paper can be made even at home. But it will be of poor quality.

Nowadays, cellulose is chemically produced using technological processes. For the production of high quality paper, the following ingredients should be included in its composition:

• Sizing is hydrophobic, which prevents spreading of ink on paper. They do not show on the reverse side of the sheet. As a sizing we use rosin glue.
• Resin, glue or starch. Thanks to these substances paper made of wood becomes more durable and resistant to various influences on it.
• Kaolin, talc or chalk make the paper less transparent, increase its density.

Types of wood

It can be hard and soft. The first type of wood is obtained from coniferous tree species: pine, fir, spruce, sequoia and zug. Softwood is obtained from broad-leaved species: beech, maple, poplar, birch, oak. In regions with tropical climate - from teak, black and mahogany.

Paper made of wood of these species is highly valued. But they, unfortunately, grow slowly. They cut down more than reproduce. Therefore, in the tropical forests of trees, valuable species becomes less.

Paper production today

The real paper is the one that is producedfrom the mass, the individual fibers of which are obtained by diluting the cellulosic material. The mass is first mixed with water, and then scooped out by the form on which the net is stretched. Excess water drains, the mass dries, a sheet of paper is obtained. This is how the Chinese citizen Cai Lun received his first piece of paper. During this time, although it took about two thousand years, no significant changes occurred.

Today, paper production is carried out onModern factories with huge shops, on the equipment of which different operations are performed. After the production of wood pulp, the fibers are shaped and structured, for which the paper stock is mixed with adhesives and resins. The glue repels water from the paper, and the resin prevents spreading of the ink. Paper made of wood, the photo of which is presented for viewing, does not need such processing for printing needs, as the ink does not spread.

The next step is staining. For this, the paper is placed in a mixer with pigments or dyes. Then the pulp enters the machine, which is called papermaking. After all stages of processing in this machine, the mass becomes a paper roll, which runs through many rollers: one squeezes water, the other - drains the tape, the third - polishes.

At the next stage, the paper is sent to thewet pressing. Here, the fibers are degreased and further compacted. The result is dry paper made of white wood, rolled up into huge rolls, which are transferred to the printing press. There they are cut according to the required dimensions.