History of paper

According to the tradition, the first paper was made by  Ts’ai Lun,  eunuch in the  Eastern Han courtyard of Chinese Emperor Ho Ti, in 105 AD. Likely as the material used in this was mulberry tree bark, and the paper was produced on the form, made of bamboo slats.

 

Paper production

 

The oldest of the surviving paper was made from a piece of cloth around 150 AD. During the first 500 years the paper produced only in China, but in 610 production penetrated in Japan, and about 750  in Central Asia. In Egypt, the paper appeared about year 800 but it was started to be produced it only after 900.

In Europe, the Moors first started using paper, and the first production of the paper appeared in Spain around 1150. In later centuries, this craft spread to most European countries. The appearance of movable type in the middle of the XV century, contributed to the development of printing, which in its turn significantly stimulated the production of paper. In England, the first paper mill appeared in 1495, and in America in 1690.

Paper production

 

The only satisfactory raw material for production of paper, known in Europe at the time, was a piece of cloth, and in the XVII and XVIII centuries, the increasing use of paper has led to a shortage of material. At the same time there were attempts to invent replacement for this raw material, but none proved satisfactory from a commercial point of view. In addition, at the same time one tried to reduce the cost of paper, designing a machine that could replace the manual process of molding used at the time for making paper. The first machine, which had successfully applied in practice, was created in 1798 by a French inventor Nicolas Louis Robert. Then the machine was improved Robert British traders of stationery, brothers Henry and Sealy Fordriners who in 1803 built the first machine that bears their name. Cheap raw materials for the production of paper was found when, around 1840, the process of making pulp from wood pulp was invented, and ten years later the process of pulp chemical production.

Paper production

 

Manual manufacturing of paper

For more than 2000 years the basic process of paper production has not changed. It includes two steps: grinding the raw material in the water to form a slurry of individual fibers, and the formation of the fibers matted fabric by applying a slurry of a suitable porous surface through which excess water is removed.

Paper production

In the manual paper production, the raw material – straw, leaves, bark, rags, or other fibrous material – is placed in a vat or trough, and pounded with a help of heavy pestle or hammer to separate fibers. In the initial phase of the operation material is washed under running water to remove impurities, but after the fibers are sufficiently separated, they are kept in suspension and the water in the tank will not change. At this stage the liquid material, also called a half, is ready for  the papermaking process. The main instrument of paper manufacturing is a form of reinforced sheet metal mesh having a structure that forms a square cell, the so-called vellum, or the structure formed by a rare longitudinal wires, which are connected together by thin cross-wire, the so-called laid paper (corrugated). The structure of the form is printed on the finished sheet of paper, and so paper made by hand, if it is not subjected to further processing, is of two types, laid paper or vellum, depending on the form of the grid structure. The form is placed inside a removable wooden frame called a deckle, which forms a low rim around the grid. Then shape and deckle are dipped into a vat of half-stuff, when the form and deckle are retrieved from the vat, mold surface is coated with a thin film of a mixture of fiber and water. Then the device is shaken in the longitudinal and transverse direction. This shake has a double effect. On the one hand, the mixture is evenly distributed over the surface of the mold. On the other hand, the individual fibers are intertwined with its neighbors, giving the canvas necessary strength. During the shake most of the water from the mixture goes through the cell shape. After this device with the generated blade wet paper is put aside. You should  wait as long as the paper web is sufficiently related in order  the deckle could be removed. Since the deckle was removed from the form, it is inverted and paper sheet is evenly shift on the woven rug (cloth). The other cloth is placed on the top of the paper web and the process is repeated. This process of shifting paper with cloth is called gauching. When the large stack of paper with cloth appears , it is placed in a hydraulic press and subjected to a pressure of 100 or more tons, thus removing most of the water  which paper contains. Then the sheets are separated from the cloth, put in a pack and pressed. Compression of  the paper stack is repeated several times, and each time sheets in the stack are folded in a different order so that individual sheets turn to be in a new position in the reference to each other. This is called a permutation, and the process of repeating  improves the surface quality of the finished paper. The final stage of paper manufacturing is drying. Paper is hung on a clothesline in a special drying room in groups of four or five sheets and remains there until almost all the moisture evaporates.

Paper production

Paper for writing or printing requires further treatment after drying, because without this treatment it will absorb the ink and the letters will be blurred. This treatment consists of sizing paper by immersion in a solution of animal glue, drying sized paper and final pressing operation between sheets of metal or smooth cardboard. Number and press force determine the structure of the surface of the finished paper. Grades of paper with a rough surface are pressed with a light load in a relatively short time, and with a smooth surface – with a heavy load during  long time.

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