Paper bag is a container made of paper that can be pulled together at the top to close. People use paper bags for a variety of purposes, such as shopping, product packaging, and shipping.
Common styles of paper shopping bags include both the flat, envelopelike bag and the square-bottom bag. Tucks in the sides of the square-bottom bag called gussets increase its capacity. Examples of square-bottom bags include paper grocery bags and popcorn bags.
Shipping bags require strength to secure heavy materials during transport. The most common of these bags, the multiwall bag, consists of several layers of paper and has a gusset. To secure a multiwall bag for shipping, manufacturers may sew the open end closed after filling the bag. Alternatively, they may insert the product into the bag through a paper valve at one of the bag’s two glued ends. Examples of multiwall bags include pet food bags and cement bags.
Widespread use of the paper bag did not begin until the 1870’s. Before that time, manufacturers shipped most goods to storekeepers in bulk (loose or unpackaged). Customers carried their purchased goods home from the store in their own containers. Customers who did not bring a container received their goods wrapped in a horn-shaped twist of paper called a cornucopia. As trade developed, many storekeepers began to make such containers in advance. They rolled up the ends of the paper to form packages ready for quick use.
In 1852, the American inventor Francis Wolle built the earliest known machine for making paper bags. The Union Company of Pennsylvania improved on the designs of early bag machines and established the Union Bag Company in 1875. Early machine-made paper bags resembled envelopes. In 1870, the American inventor Margaret Knight founded the Eastern Paper Bag Company. In 1871, Knight won a patent for a machine that cut, folded, and pasted paper into square-bottom bags.
