How cardboard boxes are made

Boxes ship flat. The first pre-cut ones came from a printer's accident when a creasing ruler shifted and cut instead.

stations: 5
things upstream: 54
raw sources: 17
steps from the ground: 9

The short version

A cardboard box begins as a flat sheet of corrugated board. A printing and cutting line prints the artwork, scores the fold lines, cuts slots to make flaps and glues one edge into a joint. The box ships folded flat to the packer, who sets it up, fills it and closes it with tape.

Print the artwork

Flat sheets of board pass through a press that prints the logo and handling marks directly onto the surface, usually with flexographic plates. Fine flutes give a smoother surface for sharp graphics.

Goes in
Cardboard Ink
Crease the fold lines

Wheels or a die crush grooves into the board along every line where it will bend. The creases let the box fold cleanly without cracking.
Slot and cut the flaps

Blades cut slots between the creases, which free the flaps that will fold shut. Die cutting can score and slot in one pass.
Glue the joint

A folder-gluer machine folds the blank over on itself and glues one edge, called the manufacturer's joint. Staples or tape can do the same job.

Goes in
Adhesive
Bundle flat

The boxes are knocked down flat, counted into bundles and strapped. Shipping them flat saves enormous space until the packer opens each one.

End of the lineCardboard box Next it goes into soap, toothpaste, deodorant and 38 more.

Worth repeating

Robert Gair invented the pre-cut paperboard box in 1890 after a metal ruler that creased bags shifted during a print run and cut them instead.
The first paperboard carton was produced in England in 1817.