Experienced graphic design and production professionals understand that there is a great deal to know about paper if you want to get the best possible combination of price and performance. A good start is to simply get command of the basic paper types, their characteristics and uses.
Paper in its initial state is uncoated. Although certain grades can be used as is (i.e. newsprint, offset, …), some customers prefer one of its two possible transformations:
- supercalendered paper
- coated paper
Newsprint is the preferred choice for most newspaper publishers because it combines low cost and high strength. It's an uncoated groundwood paper with an average brightness of 56, an off-white cast and consists mainly of wood pulp. It also has the ability to accept four-colour printing inks with final quality that is suitable for the needs of most newspaper advertisers.
Offset paper is an uncoated paper with an average brightness between 88 and 96. It has reasonable rigidity, good opacity and a smooth surface, giving excellent printing results even over long runs. An example of a paper in this category is Enviro 100, which is a recycled paper containing 100% post-consumer fibre, made from de-inked pulp and is FSC certified.
Supercalendered Paper (SNC/SCB/SCA/SCA+/SCA++)
One way of making paper easier to print on is using steel rollers (also called calenders) to apply pressure and heat to the paper. The calenders can be either hot or cold depending on the desired texture. The more calenders the paper goes through, the thinner and glossier it becomes. SNC paper usually goes through two sets of calendar rolls and has a gloss level of 63. SCA+/SCA++ paper goes through five or more sets of rolls, thus achieving a gloss level of up to 73. One existing trend is to use supercalendered papers (ex. SCB+) for special sections inside a newspaper
The Supercalendering Process
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About 40% of papers used for printing and writing are coated. Coated paper is divided into two sub-categories: coated groundwood and coated freesheet. In both cases, the base paper is coated with a latex pigment to impart certain qualities to it. This transforms the rough and macro-porous surface of the paper into a more uniform one to improve certain characteristics (gloss, for example) and the final printing quality. After the coating has been applied, calenders are used to impart the surface characteristics (finish) to the paper. This finish can either be gloss, dull, satin or matte.
To learn more about paper stocks, contact us.