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Papermaking craft in the world

 

Materials preceding invention of paper


      First of all we must askwhat is true paper? According to Bronislaw Radwan "the structure of paper differs from those of other common sheet materials in a unique way:
unlike plastic films and metal foils paper in fibrous;
unlike woven cloth, it is composed of single short fibres, arranged largery at random instead of in a regular array; unlike woven cloth or woven felt, or leather, it is laminar in that each fibre is disposed largely in plane of the sheet, and occupies a particular level within its thickness." parchment wedding invitation paper structure
The petuliar fibrous structure of paper is formed from a dilute suspension of cellulose fibres in water onto the scren that is fine enough to retain most of the fibres. A fibre may only become a part of the fibrous structure of paper if it is in contact with, at least three other fibres. The manufacture of paper must be prceded by the isolation of the cellulose fibres from vegetable raw materials. Usually, the cellulose fibres are beaten in order to facilitate the sheet formation on the screen. During the beating the fibres become more plastic and reach a considerable degree of hydration and fibrillation.This effect could not be obtained during soaking of the fibres in water, even of very long duration. Additionaly, the fibres ar shortened and create fines. Due to the above effects of beating th drainage rate of the fibre suspension on a screen becomes slower and the structure of the formed paper becomes hipogenous, with an increased surface of the contacts betwen fibres which favour the formation of bonds.After sequent stages of consolidation (pressing, drying and possibly glazing) the fibrous structure (formed on the screen) is being transformed into paper of considerable strength properties. Hydrogen bonds are now generally accepted as being the agent which holds a sheet of paper together.
      Long time ago the mn had noticed the ability of cellulose fibres to form the tough structures and began to make materials from fragments of the vegetable fibrous tissue, but without its disintegration into individual fibres. Papirus is the most famous material of this kind. The oldes of the discovered written papirus rolls date back nearly 5000 years. The secrets of papirus making by the ancient Egyptians have been rediscovered by Hassan Ragab after more than ten years of research and intensive labour (Doctoral Thesis in 1979, at Institute Nationale Polytechnique de Grenoble, France). Now in his Papirus Institute in Cairo, Egypt, the papirus is still being made. Out of the whole long stem of papirus plant only two feet cuts from the lower part are used in sheet making. The uncovered pitch is cut into thin strips which then are immersed in water. Next the strips undergo a rolling with a heavy wooden roller to increase their hydration degree. The wet strips are placed side by side on a board in two layers, one at right angle to the other, to form the sheet, which is pressed before being dried.
      Bark cloth is the lesser known another paper-like material, now generally called tapa (as used in Hawaiian region). The birth of bark cloth manufacture took place presumably about 2500 B.C. Tapa making was practised on the huge area, forming a belt around our globe (Fig 5). The barkcloth was mainly used for clothing, blankets, curtains etc. As a writing material it was used only in Mesoamerica (since 8th century), and on the isl of Java (since 17th century), and perhaps in ancient China. The raw material for the tapa are strips of inner bark (the bast layer) from trees belonging to families Moraceae and Thymelaeceae. The bast strips ar cooked in a lye from wood ash, and then the strips are rinset thoroughly in water. The fibrous strips still moist -ar beaten on the pounding board with hand-held wooden mallets or with other tools. The strips were laid out side by side an then made to cohere by pounding into small shets that were later combined to form large pieces of bark cloth.
      According to Dard Hunter, the eminent American paperhistorian, the making of tapa constitued the starting point to papermaking technology. If anyone of manufactures of tapa would proceed one stage further to disintegrate the strips of bast into the individual fibres and to form a sheet (from a dilute suspension of the fibres in water) into screen ? one would obtain true paper.

love wedding invitation

 

Ts'ai Lun ? the inventor of paper



      During the reign of Han dynasty (founded by Liu Pang) China became the powerful empire, comparable with Roman Empire. The reign of Han dynasty is devided into two periods: Western Han dynasty (206 B.C. - 9 A.D.) and Eastern Han dynasty (23-220), split by a short period of usurpation of Wang Mang. In 111 B.C. emperior Wu Ti incorporated to China for ever the southern provinces, where bark cloth making was practised. Most probably the bark cloth making began to spread on the territories situated farther northward, aherever a possibility existed to gather the inner bark of mulberry trees, feeding the silkworms with their young leaves. The coincidence may have given rise to the idea to indicate ? at a later date ? silk and paper with the same radical (phonetic transcription of the Chinese ideogram: tcheh, chih, or zhi). Presumably, the bark cloth in use for writing was indicated in antient China in the same way; the mentions are preserved dating back to the times before Ts'ai Lun. But first of all, the bark cloth was in use for lots of common purposes, such as: clothing, curtains, blankets (for the living as well as for dead), sunshades, umbrellas, and many other uses. The posterior chinese sources consider these reports as referring to paper. Additional indistinctness arises from the archeological excavations, in which paper have been found ? or rather pre-paper material (bark cloth) ? dating back to times before 105, i.e., the date of the invention of paper by Ts'ai Lun. These are the reasonswhy it is often considered that Ts'ai Lun had only summed up the experiences of his predecessors and improved the art of papermaking to produce paper of higher quality. Probably, this statement also reflects the peculiar Chinese approach to history, in which ? according to French sinologist claude Larre ? the achievements of Han people (living far northwards from River Jang-tsy) are favoured, with a tendency to neglect the accomplishments of the people who inhabited the territories arround today's Shanghai (ancient kingdom Wu) as well as the people living far to South, nearby of today's Canton (antient Kingdom Jue).     Pinterest  

 




 

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