Derived from cellulose fibers of plants, paper was initially made from flax or the same material used for linen cloth. In the early days, linen rags were recycled as paper. Paper is also one of the oldest types of flexible packaging. In contrast to other types of packaging--i.e., rigid--flexible packaging does not require as much material to wrap a product and thus contributes less weight to transport.
      Origins and Migration
Among the great inventions of ancient China, paper-making began in the Western Han Dynasty (206 B.C. to 23 A.D.), where hemp was pounded into coarse paper. According to CultureChina.org, Ts'ai Lun, a member of the court during the Eastern Han Dynasty (25 to 220 A.D.), created a thin, delicate paper out of wheat stalks, bark, hemp and other materials.
This inexpensive paper could be used for calligraphy. The invention fanned out to other parts of Asia and, by the 8th century, had found its way to the Arab world via the Silk Road. Four hundred years later, the technique of paper-making was discovered by Europe, and paper mills cropped up in Italy. Paper-making finally arrived in the United Kingdom in 1310 and then in Germantown, Penn., in 1690, reports the University of Florida.
      Wood Pulp
In the early 1700s, the demand for paper exceeded the supply of linen rags. According to the American Chemical Society, French naturalist and chemist Réné de Réaumur pointed out that if wasps can create paper from wood, then mimicking this ability may present an opportunity. His research and related studies led to the exploration of pulping techniques. By 1867, the processing of wood pulp for cellulose fiber had been successfully developed.
      Paper Bags
Although paper bags were initially made in 1844 in Bristol, England, Francis Wolle invented a machine that could produce bags in the United States in 1852. During the 19th century, progress in paper-making also included the gusset design and glued paper sacks, according to the University of Florida. By the turn of the century, machinery had evolved to manufacture in-line printed bags.
      Paperboard
Paperboard (also cardboard) or firmer paper that can be shaped into a cereal box was introduced in the United Kingdom in 1817. By the 1850s, a new type of cardboard--strong, light and inexpensive--was made of delicate wave-shaped paper layers wedged between flat sheets. Shipping cartons built of corrugated cardboard began to replace wood crates, as put forth by Ohio State University.
      Carton
Brooklyn printer and bag-maker, Robert Gair, chanced upon the invention of the carton. At the time, a metal rule was used to bend bags. While printing seed bags to fill an order, Gair's metal rule slipped from its place and sliced the bag, reports Ohio State University. Gair reasoned that creasing and cropping paperboard in a single operation would be a beneficial development. This led to the invention of semi-flexible packaging or folding cartons that are commonly used for processed foods.