Processed materials

Paper

Paper is a fibre-based material produced from wood, rags or organic material. The types of paper used in the packaging and graphic arts industries typically use wood and/or recycled paper and board, which is then chemically or mechanically processed to produce cellulose pulp. This pulp is bleached and processed in a paper making machine to produce reels of paper which may optionally be coated or finished to provide a better surface and/or improved visual appearance.

Paper may be between 0.07 mm and 0.18 mm thick, with paper for printing and packaging applications generally being in a range between 60 and 120 gsm. The crossover point between paper and board is normally considered to be around 160 grams per square meter (gsm), as it is only at this level that a fibrous material is likely to be stiff and rigid enough to make a container.

Paper has a wide range of industrial applications including use for the packaging of products as diverse as confectionery and cigarettes, as a component in packaging laminates, and for many commercial print uses.

Carton board

Carton board (also called cardboard, paperboard or solid board) is the name for a range of paper based materials that includes folding box board (FBB, GC or UC), solid bleached board (SBB, SBS, or GZ), solid unbleached board (SUB or SUS), white lined chipboards (WLC, GD, GT, or UD), some unlined chipboards, and certain laminated boards.

To manufacture carton board, fibrous material, either from trees, recycled paper, or a mixture of the two, is turned into pulp. It is then bleached and processed in a board making machine to create a board consisting of one or more layers, which may optionally be coated to provide a better surface and/or improved visual appearance.

The crossover point between paper and board is normally considered to be around 160 grams per square meter (gsm), as it is only at this level that a fibrous material is likely to be stiff and rigid enough to make a container.

Cartonboard is primarily used in the packaging industry to produce all types of folding cartons, but may also be used for graphics applications. For folding cartons the board used will normally be in the range 200 to 600gsm, or 350 to 800 microns.

Corrugated board

Corrugated board is manufactured by combining lining paper with a fluting medium in a unit called a single facer. The liners used may be made from recycled, test, or kraft papers, and will consequently have a brown or white surface, which may be coated or semi-coated, depending on the application they are to be used for. Fluting medium is generally recycled paper.

In the single facer unit, heat, steam, and a corrugating roller are used to corrugate the fluting medium, which then has the liner attached. This creates single face, the basic building block of all corrugated board. Single face is used 'as is' for some specific applications such as litho-lamination, but is normally combined with further liners and fluting media to produce single wall corrugated (single face plus a top liner), double wall (single wall plus single face), or multi-wall (further combinations of the above).

The thickness of the corrugated material will depend on the fluting height created by the single facer and the combination of flutings used. The range of thicknesses can vary from 0,5 mm for the finest, up to 15 mm for the thickest, and sometimes more. The most commonly used grammages are in the range from 80 gsm to 300 gsm, however for some specific applications lighter or heavier papers may be used.

Linerboard

Liner board is a paper product made up of layers of chemically and/or mechanically processed wood pulp along with added coatings.

Similar to carton board, paperboard, cardboard, kraft board, and solid board, the product is used extensively in the packaging industry.

Liner board is generally found in grammages from 120 g/m2 to 800 g/m2.

Some liner boards use solely virgin wood pulp, while others include recycled paper fibers. Liner board may be bleached or unbleached depending on the application.

Heavy solid board

Heavy solid board is a type of carton board with a high basis weight.

To manufacture heavy solid board, fibrous material, either from trees, recycled paper, or a mixture of the two, is turned into pulp. It is then bleached and processed in a board making machine to create a board consisting of one or more layers, which may optionally be coated to provide a better surface and/or improved visual appearance. The resulting board will normally be heavier than 1000 grams per square meter (gsm).

Heavy solid board is primarily used in the packaging industry for applications where a high level of mechanical strength is required, such as trays for meat products or puzzle.