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130 years ago, the American Albert L. Jones was granted a US patent for single face corrugated board and a few years later for double face corrugated board. The attributes of this material that made it great for packaging – secure, lightweight, sturdy, space-saving, cheap – guaranteed that it would become the leader in container making. In Germany alone, approximately 4.3 million tons of corrugated board were produced in 2006.

The primary raw material for corrugated is the secondary raw material recovered paper which, in the German sector of the corrugated board industry, makes up over 70% by weight (the browner the board, the more unbleached sulphate pulp - i.e. virgin pulp - it contains).

In production, a paper web is fed between two fluted rollers and, by means of heat, the paper material becomes fluted itself. Two continuous lengths of cover paper (liners) are then glued to the fluted sheet at the same facility. Modern corrugated board machines are so fast that it would take your breath away if you saw them in action. The paper runs through the machine at a speed of 200 metres per minute with the result that 500 m² of corrugated board are produced.

The designation of the flute type is based on the size of the flutes. Coarse flutes, medium flutes and fine flutes have a spacing between each flute of between 5 and 10 mm with flute heights from 2 to 5 mm. Quite new is the micro-flute, which has a spacing of about 3 mm and a height between 1 and 2 mm.

In addition, the industry makes many variations of the board available: single face corrugated board (sometimes called corrugated board rolls), double face corrugated board which also has only one fluting layer but two liners, and the multiple fluting layer boards which are those that have two fluting layers with two liner sheets plus an intermediate sheet as well as the three fluting layer version which has two liner sheets plus two intermediate sheets. But the science of corrugated boards can be even more complicated. The individual layers do not have to be made out of identical materials – depending on the requirements regarding price, stability, appearance or environmental attributes, there are innumerable combinations of material that can be chosen by the corrugated board manufacturers. The various grades are divided into classes which are defined in the DIN standard 5546 (German industry norm). Liners and intermediate layers (in multi-walled boards) are made from such materials as Kraft liner, Duplex (white test liner) or bogus paper. Fluting medium are made from wellenstoff (100% waste based material) or semi-chemical pulp.

Sturdy Kraft liner consists of chemically solubilized virgin fibres (sulphate pulp) and is only imported. White top liner is Kraft paper that has been covered with white paper (for cost and environmental reasons it is not bleached); test liner consists of a carrier layer made from recycled paper that is couched together with a sulphate pulp which serves as the cover layer (couching is a process whereby still wet paper rolls are pressed against one another thereby causing the fibres to bind to one another). Bogus paper is a low quality paper made from recovered paper. Fluting material is the inner layer that is made exclusively from recovered paper, the stronger semi-chemical pulp is fabricated out of chemically solubilized pulp derived from recovered paper.

Perpendicular to the flute direction, corrugated board is very stiff, but parallel to the flutes it will bend. The flute direction can be seen when looking at the liner and, of course, runs parallel to the resulting lineal texture of the board. The first measurement given as to the size of the board (length and width) always refers to the parallel running corrugations. Modulor´s designation should therefore be read according to the following example:
700 x 990 means that the flutes run parallel to the width of the board while 990 x 700 means that the flutes run parallel to the length of the board.

The mass per unit area is always calculated according to a predetermined constant. The constant for the E-flute is 1.25, for the B-flute it is 1.35. The mass per unit area for a single face E-flute made with a liner of 125 g/m² test liner and a 115 g/m² wellenstoff will be 268.75 g/m² (= 125 g/m² + 1.25 x 115 g/m²).

We have listed the configurations of the corrugated boards that we have on offer at each individual article. We do reserve the right to change the specifications. If a specific grade or quality is important for your satisfaction, please don’t hesitate to inquire about it.

In addition to the corrugated boards that we have in stock, we can also provide you ones that are configured differently as well as different types of board: double wall/single face corrugated board, double wall corrugated with no liners , tri-wall corrugated board, etc...

Corrugated board designation as per DIN 55468; we abbreviate flute spacing with “s”, flute height with “fh”