Design Context: OUGD504 - Design For Print: Stock

Coated
Coated paper is paper which has been coated by a compound to impart certain qualities to the paper, including weight, surface gloss, smoothness or reduced ink absorbency.
Kaolinite, calcium carbonate & Bentonite are used to coat paper for high quality printing used in packaging industry and in magazines.
The chalk or china clay is bound to the paper with synthetic viscofiers and natural organic binders such as starch.
The coating formulation may also contain chemical additives as dispersants, resins, PE: to give water resistance and wet strength to the paper or to protect against ultraviolet radiation.

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Uncoated
Uncoated paper is typically used for letterheads, copy paper, or printing paper.
Most types of uncoated paper are surface sized to improve their strength. Such paper is used in stationary and lower quality leaflets and brochures.
This type of paper is generally more absorbent than coated so isn't recommended for use of images.

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Coloured
Coloured paper is uncoated. Colour pigments are added during the production stages of making the paper.

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Duplexing
A duplex is the pasting together of two sheets of stock, making one thicker sheet in the end.
Duplexing two sheets together after printing offers a clean look if done correctly. It also makes sure the designs on each side won't be compromised by each other. This gives the opportunity for processes such as embossing or letter pressing (something with an indentation) to be used.

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The 7 categories of paper:

Printing papers of wide variety.
Wrapping papers for the protection of goods and merchandise. This includes wax and kraft papers.
Writing paper suitable for stationery requirements. This includes ledger, bank, and bond paper.
Blotting papers containing little or no size.
Drawing papers usually with rough surfaces used by artists and designers, including cartridge paper.
Handmade papers including most decorative papers, Ingres papers, Japanese paper and tissues, all characterized by lack of grain direction.
Specialty papers including cigarette paper, toilet tissue, and other industrial papers.

Cotton paper
Cotton paper is made from cotton linters or cotton from used cloths as the primary material source, hence the name rag paper.
Cotton paper is superior in both strength and durability to wood pulp-based paper, which may contain high concentrations of acids.
Cotton paper is used in some countries' modern banknotes. These banknotes are typically made from 100% cotton paper, but can also be made from a mixture of 75% or less.
Cotton bond paper can be found at most stores that sell stationery and other office products. Though most cotton paper contains a watermark, it is not necessary for it to have one.Higher quality art papers are often made from cotton.

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Hand-made paper
Paper-making, regardless of the scale on which it is done, involves making a dilute suspension of fibres in water and allowing this suspension to drain through a screen, so that a mat of randomly interwoven fibres is laid down.
Water is then removed from this mat of fibres using a press.
The method of manual paper-making changed very little over time, despite advances in technologies. The process of manufacturing handmade paper can be generalised into five steps:

Separating the useful fibre from the rest of raw materials. (e. g. cellulose from wood, cotton, etc.)
Beating down the fiber into pulp
Adjusting the color, mechanical, chemical, biological, and other properties of the paper by adding special chemical premixes
Screening the resulting solution
Pressing and drying to get the actual paper

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Kraft paper
Kraft paper is paper or paperboard (cardboard) produced from chemical pulp produced in the kraft process.
Sack Kraft Paper, or just sack paper is a porous kraft paper with high elasticity and high tear resistance, designed for packaging products with high demands for strength and durability.
Pulp produced by the kraft process is stronger than that made by other pulping processes.
Kraft pulp is darker than other wood pulps, but it can be bleached to make very white pulp. Fully bleached kraft pulp is used to make high quality paper where strength, whiteness and resistance to yellowing are important.
Kraft paper is used paper sacks for cement, food, chemicals, consumer goods, flour bags etc.
Kraft papers are used in paper grocery bags, multiwall sacks, envelopes and other packaging.
Kraft paper is an inexpensive material for lining particle boards.
The base paper for sandpaper is normally kraft paper.

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Newsprint
Newsprint is a low-cost, non-archival paper most commonly used to print newspapers, and other publications and advertising material.
Invented in 1844 by Charles Fenerty, it usually has an off-white cast and distinctive feel.
It is designed for use in printing presses that employ a long web of paper (web offset, letterpress and flexographic) rather than individual sheets of paper.
Newsprint mainly consists of wood pulp.
Newsprint is favored by publishers and printers as it is relatively low cost (compared with paper grades used for glossy magazines and sales brochures), strong and can accept four-color printing at qualities that meet the needs of typical newspapers.