It is made from wood, from which cellulose fibers are extracted, converted into paper after a series of industrial processes. What few people know is that it was not always this way. Paper was invented in China in the 2nd century, but for over 1500 years the most common raw material for making it was not wood, but cotton fibers extracted from old clothes, cloths and rags.
After printing machines began to develop, starting in the 15th century, paper consumption increased a lot and the world realized that there were not enough old clothes to publish books, magazines, newspapers… Some kings of Europe even tried to limit the trade in rags, fearing running out of paper. Although the Frenchman René Antoine de Reaumour came up with the idea of using fibers extracted from wood in 1719, it was only after 1850 that several inventors, such as the German Friedrich Keller, the Englishman Hugh Burgess and the American Benjamin Tilghman, made this feasible. .
It was necessary to perfect a method of “digesting” the wood with chemical products, in order to extract the cellulose and obtain a paper of acceptable quality. Among the chemicals used are certain sulphites (sulphur compounds) – this is where the name, for example, of paper “sulfite” comes from. Today, with advanced methods, it is possible to take advantage of up to 98% of the wood from a tree in a paper factory, using the bark and other previously discarded parts as fuel for the industrial process itself. In essence, however, the manufacturing method is still the same, since its invention by the Chinese.
From wood to sheet Manufacturing process begins with a “stew” of tree chips1 – The main raw material for paper production is wood logs. In the factories, after being cut, they pass through a peeler and chopper, from where they come out in the form of small chips (chips)
2 – In a tank called a digester, the chips are cooked in a liquid composed of water and some chemical agents, such as sulphites. The result of this cooking is called pulp.
3 – The pulp undergoes a washing process, in tanks and centrifuges, where the chips that did not dissolve and other impurities are extracted. Afterwards, it is left to rest in other tanks, in a step called bleaching, to separate the cellulose from other residues.
4 – Unused wood residues are burned in boilers and transformed into electricity in steam turbogenerators. The energy generated here feeds the papermaking process itself.
5 – The cellulose pulp, still with a high water content, passes through a machine called a flat table, which transforms this wet mass into a large continuous and smooth sheet, resting on a felt conveyor belt
6 – The large sheet, moved by the conveyor belt, passes through pressing rollers and drying with hot air, which remove excess water, compact the paper and smooth the sheet. Depending on the type of product you want, it still goes through the coater (coater), a roller that applies a film that protects or adds shine to the paper – as in the case of coated paper, for example.
7 – Finally, the sheet passes through a device called a winder and through rewinding rollers, where the paper is detached from the conveyor belt and forms huge rolls – or coils -, being ready for cutting and packaging
China business Paper emerged in the 2nd century, replacing papyrus and parchment.4000 BC – Egyptian CREATIVITY
The ancient Egyptians discovered that they could assemble soft writing sheets from the pith of the cane that grew in the swamps of the Nile River. After being cut, the canes (Cyperus papyrus) were arranged side by side in two perpendicular rows of fibers, were pressed and put out to dry. Papyrus was the great medium for writing in antiquity, being used by Greeks, Romans, Persians and Arabs for many centuries.
2nd Century BC – Animal Idea
Unlike papyrus, which has a vegetable origin, parchment was made with the leather of animals (such as sheep, goats and calves), which was cleaned, tanned, sanded and stretched on wooden frames. It is believed that it was invented in the Greek colony of Pergamum (present-day Bergama, Turkey), hence its name. After the year 700, when the Arabs conquered Egypt, the main supplier of papyrus in the world, parchment became the most important means of writing in Europe
2nd century AD- Recycled clothing
In the year 105, the Chinese T’sai Lun, wise man of the Han emperor’s court, mixed clothes rags, ropes and cork in a vat, put it to cook and collected the pulp formed in smooth wooden trays. Afterwards, he pressed the trays to remove excess liquid and hung the leaves to dry in the sun, on a clothesline. Paper was invented, which would still take a thousand years to reach Europe. Europeans learned to manufacture it from the Arabs, who in turn had learned from the Chinese.
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