Paper production begins with wood, which is processed by stripping the bark, shredding it and turning it into pulp. (Photo by Michael Milner/Getty Images)
Paper is present in our daily lives, but how exactly is it created and where does it come from?
The ancient Egyptians created an early form of plant paper from papyrus, which is where the word “paper” comes from. They extracted fibers from the stems of the papyrus plant (Cyperus papyrus), a marsh reed that can grow up to 5 meters (16 feet) tall. The Egyptians layered the fibers, moistened them, and then pressed them to make sheets. These sheets were used to write letters, record administrative documents, and create stories and religious texts.
More than 2,000 years ago, a process closer to modern papermaking was developed in China: hemp plants were boiled into a pulp, formed into sheets, and dried. The method moved west to Baghdad about 1,400 years ago, where the city became known for its papermaking and began selling paper and books.
Paper then made its way to Europe, where medieval Europeans made it from linen and cotton rags that were soaked and processed. The first rag paper factory opened in the North American colonies in 1690.
Over time, paper mills experienced a shortage of rags, and manufacturers turned to a more accessible and cheaper material – wood.
The first newspaper in the United States printed on paper made from wood was the Boston Weekly Journal, which appeared in January 1863.
Today, the papermaking process begins with loggers cutting down trees and transporting them to paper mills: these can be conifers such as pine, spruce, and fir, or deciduous trees such as oak, birch, and eucalyptus. Machines strip the bark, the inner wood is shredded into small pieces, and these pieces are boiled into a sticky pulp. How much and how the pulp is boiled depends on the desired characteristics of the final product: if the paper needs to be stronger or less opaque, the pulp is boiled and processed more intensively.
Cell walls of wood cells are an important component of cellulose: the cell walls of all plants contain cellulose, known to chemists as a linear polysaccharide. These molecules are very strong and flexible. Cellulose fibers are also excellent at absorbing water while remaining strong. These properties make them ideal for papermaking.
Once prepared, the pulp is suspended in water, filtered through a woven sieve to form a sheet, pressed to remove excess water, and then dried. Previously, the entire process was done one sheet at a time, but now it is mechanized and much faster.
Paper Making Process – YouTube
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Different types and grades of paper depend on the type of pulp used, how finely it is ground or refined, added components, sheet-forming characteristics such as thickness, and chemical treatments applied at the end of the process, says Erica Redmond, a paper chemist and engineer at the State University of New York's School of Environmental and Forestry Sciences.
Sourse: www.livescience.com
