Paper

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Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags orgrasses, and drying them into flexible sheets.
Paper is a versatile material with many uses. Whilst the most common is for writing and printing upon, it is also widely used as a packaging material, inmany cleaning products, in a number of industrial and construction processes, and even as a food ingredient – particularly in Asian cultures.
Paper, and the pulp papermaking process, was said to bedeveloped in China during the early 2nd century AD by the Han court eunuch Cai Lun, although the earliest archaeological fragments of paper derive from the 2nd century BC in China.[1]
Contents[hide]
1 History
2 Etymology
3 Papermaking
3.1 Chemical pulping
3.2 Mechanical pulping
3.3 Deinked pulp
3.4 Additives
3.5 Producing paper
3.6 Finishing
4 Applications
5 Types, thickness andweight
6 Paper stability
7 Environmental impact of paper
8 Future of paper
9 See also
10 References and notes
11 External links
History

Main article: History of paper
Further information:Science and technology of the Han Dynasty and List of Chinese inventions


Hemp wrapping paper, China, circa 100 BCE.
The oldest known archaeological fragments of the immediate precursor to modernpaper date to 2nd century BC in China. Papermaking is considered one of the Four Great Inventions of China, and the pulp papermaking process is ascribed to Cai Lun, a 2nd century AD Han court eunuch.[1]With paper an effective substitute for silk in many applications, China could export silk in greater quantity, contributing to a Golden Age.
Paper spread from China through the Middle East tomedieval Europe in the 13th century, where the first water-powered paper mills were built.[2] In the 19th century, industrial manufacture greatly lowered its cost, enabling mass exchange of information and...
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