Solutions for high quality stationary papers
These high-quality uncoated papers ranging from 70-250 gsm are used in copiers, for fine writing and printing, for archival copying and offset printing. Uncoated woodfree papers are found in the office environment and in books and direct mail pieces.
These papers are made to tight tolerances for book applications and for photocopiers. Strength, bulk, smoothness and brightness are important qualities. Caliper is often specified for use in photocopiers and books. Linting and dusting must be minimized to extend the life of the photocopiers and to avoid print defects in offset printing. Recently a new bar was set for these grades in brightness. 92 GE brightness is the new standard in North America, but this high level of brightness has been the case for many years in Europe and Asia. To achieve archival quality and high brightness, calcium carbonate fillers and alkaline papermaking have become the dominant technologies to produce these grades.
Globally PCCs like IMERYS’ Opti-Cal filler range are the most common type of pigments used in this segment because of the combination of brightness, opacity and bulk that they can bring to the paper. PCC is most economical for those paper mills that have a ready source of CO2 and onsite PCC plants are commonplace in all geographies. GCC based fillers like Imerys’ Intracarb products are also used for uncoated woodfree in Europe and parts of Asia because of the ready availability of ground marble.