Semi Rigid Packaging

The use of semi rigid packaging materials began with the Chinese, They used sheets of treated mulberry bark to wrap foods as early as the first or second century B.C. During the following centuries, the Chinese also developed and refined the techniques of paper making. Knowledge of how to make paper gradually moved west across Asia and into Europe. In 1310, paper making was introduced to England. The technique arrived in America in Germantown, Pennsylvania, in 1690.

Paper is basically a thin sheet of cellulose. Cellulose is a fibrous material derived from plants. Early paper was made from cellulose fibers derived from flax, the plant that also gives fibers for linen cloth. As demand for paper grew, old linen rags were sought as a source of fiber.

In 1867, the process for deriving useful cellulose fiber from wood pulp was developed. Because wood was so cheap and plentiful, this fiber source rapidly replaced cloth fibers as the primary source of paper fiber. Today, virtually all paper has wood pulp as the source of cellulose fiber.

An important step for the use of paper in packaging came with the development of paper bags. Commercial paper bags were first manufactured in Bristol, England, in 1844. Shortly thereafter, in 1852, Francis Wolle invented the bag-making machine in the United States. Further advancements during the 1870s included glued paper sacks and the gusset design, producing the types of paper bags used today. In 1905, machinery was invented to automatically produce in-line printed paper bags.

With the development of the glued paper sack, the more expensive cotton flour sacks could be replaced. But a sturdier multiwalled paper sack for larger quantities did not replace cloth until 1925, when a means of sewing the ends was finally invented.

Another important use of paper in packaging came with the development of paperboard -- the kind of paper that packages a box of cereal. The first paperboard carton -- often called a cardboard box -- was produced in England in 1817, more than two hundred years after the Chinese invented cardboard or paperboard.

Another common form of "cardboard" based on corrugated paper appeared in the 1850s. Basically, this form of cardboard is made from thin sheets of paperboard that are molded into a wavy shape and then "faced" or sandwiched between two flat sheets of paperboard. The strength, lightness, and cheapness of this material make it very useful for shipping and storing. However, replacing wooden crates with the new paper alternative would prove to be something of a battle. Nevertheless, about 1910, after much litigation between manufacturers and the railroads, shipping cartons of faced corrugated paperboard began to replace self-made wooden crates and boxes used for trade. Today, cardboard boxes -- more accurately called "C-flute corrugated paperboard cartons" -- are used almost universally for product shipping.

As with many innovations, the development of the carton was accidental. Robert Gair was a Brooklyn printer and paper-bag maker during the 1870s. While he was printing an order of seed bags, a metal rule normally used to crease bags shifted in position and cut the bag. Gair concluded that cutting and creasing paperboard in one operation would have advantages; the first automatically made carton, now referred to as "semi-flexible packaging," was created. Such folding cartons or "tubular cartons" dominate the dried, processed food market.

The development of flaked cereals advanced the use of paperboard cartons. The Kellogg brothers were first to use cereal cartons. The Kelloggs operated a sanatorium at Battle Creek, Michigan. They developed flaked cereals as a health food for their patients, but soon began marketing this new food product on a mass scale. Their original packaging was a waxed, heat-sealed bag of Waxtite wrapped around the outside of a plain box. The outer wrapper was printed with the brand name and advertising copy. Today, of course, a plastic liner protects cereals and other products within the printed carton. Some cereal manufacturers have attempted to sell cereal in flexible pouches, like snack foods. However, U.S. consumers have only marginally accepted cereals in a pouch only, so we continue to see a bag-in-box format for cereals.

Paper and paperboard packaging increased in popularity throughout much of the 20th century. Then with the advent of plastics as a significant player in packaging (late 1970s and early 1980s), paper and its related products were replaced in many uses. Lately that trend has slowed as designers have tried to respond to the perception that plastic is environmentally unfriendly. The fact is that decreasing that amount of material in packaging is usually more important than the composition of the package to get the most environmentally friendly form of packaging.