Paper is a material made mainly from wood pulp. It is used for writing, printing, and art work, to wrap things, and even to cover walls. To make paper, woodchips are heated with chemicals, a process that turns them into pulp. The pulp is strained, washed, and put through a screen to remove any unwanted material. More chemicals are added, and the pulp is beaten until it is the correct texture. It is then put through a papermaking machine to form into sheets or rolls of paper. Finally, it is passed through heated metal rollers to give it a smooth finish.
Paper has a long history. About 5,000 years ago, the Egyptians made paper from papyrus, a Marsh reed. They used it to record business transactions, religious ceremonies, or stories and for artwork.
In 105 A.D., Ts’ai-Lun of China discovered how to make paper out of cotton or flax. The process he invented is the basis of modern papermaking. His technique was known in Korea, Japan, Tibet, and India by the 7th century and in the Middle East by the 10th century.
Until the 1200s, Europeans wrote on parchment, which was made from animal skins and was expensive to produce. After the printing press was invented in 1456, printing materials were in great demand. To meet this demand, Europeans adopted the Chinese way of making paper because it was much cheaper.
In 1690, Pennsylvania became home to the first paper mill in America. By 1810, several mills existed and rags for paper production were getting harder to find. However, about the same time, Mathias Koop of England discovered how to make paper out of wood pulp and the mills switched to it. Papermaking machines were invented soon after. Today, paper is so common that it is an environmental problem and has given rise to many recycling programs.