Papermaking is thought to have begun in China about 100 A.D. with the use of rags, cotton, and grasses as raw materials and the initial fibre separation method of beating against stone mortars. Significant improvements in mechanization over the years, batch processing methods and agricultural fiber sources remained common until the 1800s. At the turn of the century, continuous papermaking machines were patented. Between 1844 and 1884, methods for pulping woods, a more abundant fibre supply than rags and grasses, were developed, including mechanical abrasion and chemical methods such as soda, sulphite, and sulphate (kraft).
Pulp for papermaking can be made from virgin fibre through chemical or mechanical methods, or it can be produced by repulping recycled paper. The primary initial raw material is wood. Paper makes up almost half of the recycled fibres, but straw, hemp, hay, cotton, and other cellulose-bearing materials may also be used in some situations. A fibrous raw material is first processed into pulp, and then the pulp is converted into paper in a two-step process. The harvested wood is then processed to separate the fibres from the lignin, which is an unusable component of the wood. Pulp can be processed either mechanically or chemically. After that, based on the form and quality of paper to be made, the pulp is bleached and further processed. To make paper rolls, the pulp is dried and pressed in a paper factory. After being used, a growing percentage of paper and paper items are recycled. Non-recycled paper is either disposed of or burned.
Mechanical pulping, chemical pulping, repulping waste paper, papermaking, and converting are some of the main pulp and paper making methods in use today. Similar to the kinds of goods produced, the market can be split into two major industries today. Pulp is typically produced in big mills in the same areas where fiber is harvested (i.e., mainly forest regions). Most of these mills also produce paper, such as newsprint, publishing, printing, and tissue papers, as well as paperboards. Separate converting operations are usually located near consumer markets and manufacture bags, paperboards, cans, towels, wrapping papers, decoration fabrics, business items, and so on using market pulp or paper.
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