By Matt Ruggle
Note: In this article, the term “cardboard” is used somewhat interchangeably with “corrugated”. See the Wikipedia definition to understand the technical difference.
Where Does Cardboard Come From?
In the mid 1880’s, a Swedish chemist gave the world a very friendly gift. Dr. Carl F. Dahl invented the chemical process by which we get kraft paper from wood pulp, and by the early 20th century, paperboard (as it is known) was being produced widely throughout the world.
Corrugated is basically layers of this kraft paperboard – a layer of crimped kraft glued to flat kraft surfaces. This corrugated cardboard can then be folded and bound into packing boxes, and can sustain multicolor custom print jobs. (See a previous post about corrugated cardboard for finer details on various styles.)
Where Does Cardboard Go?
In the recycling process, cardboard is broken down with heat and water into pulp to remove dirt and printing ink – the pulp is very much like the pulp made from wood in the original kraft process – and, similarly, is flattened and formed into paperboard, which can become the inner and outer layers of corrugated cardboard.
Not all cardboard can be recycled, of course – coated cardboard containers like milk cartons cannot be reduced to the right kind of pulp again, nor can cardboard that’s been soaked with food grease (like pizza boxes), but recycling centers always perform filtering out of non-recyclable materials, so when uncertain, it’s better to err on the side of recycling.