How is Corrugated Cardboard Made?

Corrugated cardboard is the term given to a special kind of cardboard used to make shipping boxes. It differs from regular cardboard because it contains a corrugated sheet in between 2 flat liners. The resulting product is a light-weight, strengthened barrier that can withstand the weight of the products inside and the wear and tear of transportation.

The process begins with a “Medium” roll. The medium is the thick, flat paper. This paper is sent through a flute roller to be pressed into waves. From this point on, the medium role is referred to as a “flute.” Glue is applied to each side of the flute and pushed forward to meet an outer liner and an inner liner. Using a hot box, the glue seals the flute to its outer and inner liners to produce a sturdy board, ready for the wear and tear of shipping.

The flute does two things for the board. For one, it adds an extra layer of box to protect the products inside. For another, it allows air to help cushion and support the products inside.

In instances when the box needs to handle more than the average corrugated box, the machine will double layer the final product. Two sheets of flute will be pressed and placed between three. The corrugated cardboard has the following make-up: outside liner, flute, inside liner, flue, inside liner. The result is a sturdy, durable box for heavy duty products and shipping.

Cardboard was first discovered by accident by a printer and bag maker named Robert Gair in the late 1800’s. In an odd turn of events, he accidentally cut a paper bag he was trying to crease with a metal ruler. He discovered that he could both cut and bend his paper into a box. As time went on, he got into corrugated shipping and made himself an empire for the time. His invention has shaped the way America has shipped its products for a century.