First, lists were made by hand, and the result is uneven rather coarse linen paper. In 1799 a young Frenchman, Louis-Nicolas Robert used to as a basis for pouring the pulp continuously moving grid, and the beginning of the XIX century in England, the brothers Henry and Sealy Furdrine samocherpnuyu patented machine, manufacture allows fairly good quality paper. Production of paper, depending on what type of paper must be obtained in the production process as a raw material used cellulose fibers, wood pulp or a mixture thereof. Chistotsellyuloznaya paper – the best quality and expensive, it has a high whiteness and strength. Paper made entirely from wood pulp, usually the lowest quality. The gap between the two main types of paper is a mixture of cellulose and wood pulp, which are taken in a 1:1 ratio.
The technology of modern production of paper is quite simple. Floured cellulose fibers mixed with the pulp, sizing agents (usually calcium carbonate) and close fillers. For printing paper used bleached milled kaolin, for coated – titanium dioxide, for special types of paper – zinc oxide. Fillers paper gives smoothness and flexibility, reduce its transparency and porosity. Then the pulp is fed to the grid of the papermaking machine to form a thin fibrous layer. In the press section of the machine squeezes excess water, after which the paper tape enters the dryer section. There shall drying fabric and surface sizing required for the manufacture of paper for offset printing or other moisture.
The last section of the machine is called finishing. Polished cast iron cylinder seal the paper lining the surface and then is wound tape rolls. To improve the quality of surface applied or pigmentation Coating – the application of the coating layer. In the first case, its thickness does not exceed 14 g/m2, in the second up to 40 g/m2. The urgency of office paper and its advantages over the electronic media despite the widespread use of electronic media information, office paper has not lost its relevance: many kinds of documents still are duplicated on the paper.