Paper that has been smoothed and polished between sets of rollers, called a calendar. This process is mostly done at the dry end of a papermaking machine.



See Thickness.



A thin tissue paper coated on one side with coloring agent or carbon black that is conveyed to a sheet of paper underneath when pressure in applied.



This consists of two sheets of paper. The underside of the top sheet is coated with colorless dye in minute gelatin capsules; the bottom sheet is coated with a reactive chemical that turns blue or black when mixed with the colorless dye. Pressure from a pen or typewriter on the top sheet causes the gelatin capsules to break, the dye and chemicals mix, and the blue or black copy appears on the bottom sheet.



A receptacle usually made of relatively thin carton or folding board, but sometimes partially or totally of plastic. The carton manufacturer delivers it to the user in either flat or collapsed form.



Slightly rough-coated or uncoated printing appear on the surface paper used for a variety of graphic purposes such as envelops. The name comes from the original use for the paper, which was for forming the tube section of a shotgun shell.



Large boxes made of board that are used as receptacles for packages. Cases are mainly used for transit and storage purposes.



A method of drying coated paper by contact of the freshly coated surface with a highly polished, chromium-plated, heated metal platform.



Regular Protect fragile or sensitive items with this economical cushioning. Multi-layers of lightweight, absorbent wadding conform to any shape and fill excess space to prevent items from shifting during transport. It absorbs liquids and won’t scratch delicate finishes. Expandable Use this absorbent wadding to protect a variety of items that require different densities of cushioning. As this highly compressed wadding expands, its density decreases. Taking up less space than equal amounts of other cushioning, it’s easier to store.



During the incunabula period, Europeans used rags to make paper by the following method: the rags were cut into small pieces; fermented; ground by watermill; and scooped into a mould to dry. Therefore handmade paper does not have a uniform thickness; it varies in thickness according to the mesh of the mould. If held against the light, the thinner part of handmade paper appears brighter, and it is possible to detect thick lines spaced several centimeters apart, as well as thin lines closely spaced crossing the thick lines at a right angle. The thick lines are referred to as the “chain line” and the thin lines the “wire line.”



Defect in reels due to variations in thickness across the width, resulting in the slack areas assuming a chain-like pattern around the outer border.



The ready removal, in the form of a powder, of an insufficiently bound layer of pigment on the paper surface resulting from the soaking up into the paper of too high a proportion of the vehicle of an ink.



Estimation of the oxygen demand, caused by all impurities in the water when oxidizing a sample with a strong oxidant.



See Pulp.



A natural mineral, consisting mostly of hydrated silicate of alumina, used as a filler or as a component in a coating slip.



An inexpensive board grade commonly manufactured from the lower grades of wastepaper.



A term used to describe both papers and boards used for subsequent brush coating. The different qualities are determined both by the actual grade of base material used and the quality of the coating, which may be gummed. Coating may be applied to one or both sides, depending on end use.



Material coated on one or both sides with a mixture of china clay, latex and other loadings to fill up surface pits and improve the printing surface. The process can be completed either on-line on the papermaking machine or away from the papermaking machine as a separate operation. There are a variety of coating methods, these include: roll coating, blade coating, air-knife coating and brush coating, or combinations of these types. A very high-quality form of off-machine coating is cast coating.



A layer of minerals applied to one or both sides of paper or board to improve brightness, gloss and printability. The mineral commonly used is china clay (hydrated aluminum silicate), but calcium carbonate and titanium dioxide are also used. The coating is held together and stuck to the paper by a binder.



Local distortion of a sheet of paper due to unequal shrinkage giving it a slightly crumpled appearance.



See Chemical Oxygen Demand.



A planographic printing process capable of producing high-fidelity continuous tone color reproductions, i.e., no screen is used in producing the negatives from which the plates are prepared.



Paper that has been processed in the mill by exposure to hot, moist air to increase the moisture content of the paper to what is considered to be an optimum level for flatness and stability.



These boards are made to provide a variety of product containers and are made from waste materials. They may, however, be lined with bleached or unbleached kraft, or other papers, relies on end use. Some of these boards may also be treated with plastic to provide special characteristics.



A grade widely used on modern high-speed accounting and similar machines. The paper is supplied in reel form and, along with the printing process, many finishing techniques can also be used, such as perforation and special folds. A unique use is for invoices, statements and similar documents, when it is normally fan-folded.



An image in which tonal progress is produced by changes in density.



Unsuitable material found in wastepaper that must be eliminated from the pulp before making it into paper, e.g., paperclips, string, plastics, etc.



A company that specializes in converting reels and sheets of paper and board into packaging or finished goods for sale to the public.



Treatment of fibrous raw material by heat in the attendance of water, usually with added chemicals.



Lightweight grade of good quality, used for copying correspondence and documents. May be glazed or unglazed. Most copier papers are laser eligible and special grades are made for color copying.



Board consisting of one or more sheets of grooved paper stuck to a flat sheet of paper or between several sheets. The following are the main classifications:

(a) Single face corrugated fiberboard. Board consisting of one sheet of grooved paper stuck to one sheet of facing.

(b) Single wall corrugated fiberboard (also known as double-faced). Board consisting of one sheet of grooved paper interposed between and stuck to two facings.

(c) Double wall corrugated fiberboard (also known as double-double-faced). Board consisting of two sheets of grooved paper interposed between and stuck to three facings.

(d) Triple wall corrugated fiberboard. Board consisting of three sheets of grooved paper interposed between and stuck to four facings.



Couch is the section of the wet end of the paper or board machine at which the wet web leaves the vat machine cylinder or Fourdrinier wire part or other forming surface.



The Process of crinkling paper from a roll or cylinder in order to increase its stretch and softness. This process may be carried out on or off the papermaking machine. Two types are recognized:

(a) Dry creping

An on-machine operation carried out on a dried web.

(b) Wet creping

On- or off-machine operation carried out on a wet or partially dried web.



The direction of a machine-made paper, which is at right angles to the machine direction, i.e., the direction across the direction in which the web travels. The cross direction of paper generally has less strength and folding endurance than the machine direction, although, in some papers, after aging, the opposite may be true. The cross direction has greater tearing resistance, and paper also expands more in the cross than in the machine direction when the moisture content of the paper increases.



See Thermo Mechanical Pulp.



The procedure of slitting and cutting watermarked paper without regard to where the design falls in each sheet. The design(s) may fall in different places in successive sheets and some may be cut.



The procedure of slitting and cutting watermarked paper so that the design falls approximately in a given position in each sheet.


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