HOME

TheInfoList



OR:

Paper is a thin sheet
material Material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified on the basis of their physical and chemical properties, or on their geolo ...
produced by mechanically or chemically processing
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell w ...
fibres derived from
wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin ...
,
rags Rag, rags, RAG or The Rag may refer to: Common uses * Rag, a piece of old cloth * Rags, tattered clothes * Rag (newspaper), a publication engaging in tabloid journalism * Rag paper, or cotton paper Arts and entertainment Film * ''Rags'' (1915 ...
,
grasses Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns ...
or other vegetable sources in
water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...
, draining the water through fine mesh leaving the fibre evenly distributed on the surface, followed by pressing and drying. Although paper was originally made in single sheets by hand, almost all is now made on large machines—some making reels 10 metres wide, running at 2,000 metres per minute and up to 600,000 tonnes a year. It is a versatile material with many uses, including
printing Printing is a process for mass reproducing text and images using a master form or template. The earliest non-paper products involving printing include cylinder seals and objects such as the Cyrus Cylinder and the Cylinders of Nabonidus. The ...
, painting, graphics, signage, design, packaging, decorating,
writing Writing is a medium of human communication which involves the representation of a language through a system of physically inscribed, mechanically transferred, or digitally represented symbols. Writing systems do not themselves constitute h ...
, and
cleaning Cleaning is the process of removing unwanted substances, such as dirt, infectious agents, and other impurities, from an object or environment. Cleaning is often performed for aesthetic, hygienic, functional, environmental, or safety purposes ...
. It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, or currency and security paper, or in a number of industrial and construction processes. The papermaking process developed in east Asia, probably China, at least as early as 105 CE, by the
Han Han may refer to: Ethnic groups * Han Chinese, or Han People (): the name for the largest ethnic group in China, which also constitutes the world's largest ethnic group. ** Han Taiwanese (): the name for the ethnic group of the Taiwanese p ...
court
eunuch A eunuch ( ) is a male who has been castrated. Throughout history, castration often served a specific social function. The earliest records for intentional castration to produce eunuchs are from the Sumerian city of Lagash in the 2nd millenni ...
Cai Lun, although the earliest archaeological fragments of paper derive from the 2nd century BCE in China. The modern pulp and paper industry is global, with China leading its production and the United States following.


History

The oldest known archaeological fragments of the immediate precursor to modern paper date to the 2nd century BCE in China. The pulp papermaking process is ascribed to Cai Lun, a 2nd-century CE
Han Han may refer to: Ethnic groups * Han Chinese, or Han People (): the name for the largest ethnic group in China, which also constitutes the world's largest ethnic group. ** Han Taiwanese (): the name for the ethnic group of the Taiwanese p ...
court
eunuch A eunuch ( ) is a male who has been castrated. Throughout history, castration often served a specific social function. The earliest records for intentional castration to produce eunuchs are from the Sumerian city of Lagash in the 2nd millenni ...
. It has been said that knowledge of papermaking was passed to the Islamic world after the Battle of Talas in 751 CE when two Chinese papermakers were captured as prisoners. Although the veracity of this story is uncertain, paper started to be made in Samarkand soon after. In the 13th century, the knowledge and uses of paper spread from the
Middle East The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (Europ ...
to
medieval Europe In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...
, where the first water-powered paper mills were built. Because paper was introduced to the West through the city of Baghdad, it was first called ''bagdatikos''. In the 19th century, industrialization greatly reduced the cost of manufacturing paper. In 1844, the Canadian inventor
Charles Fenerty Charles Fenerty (January 1821 – 10 June 1892), was a Canadian inventor who invented the wood pulp process for papermaking, which was first adapted into the production of newsprint. Fenerty was also a poet (writing over 32 known poems). Early ...
and the German inventor
Friedrich Gottlob Keller Friedrich Gottlob Keller (born 27 June 1816 in Hainichen, Saxony; died 8 September 1895 in Krippen, Saxony) was a German machinist and inventor, who (at the same time as Charles Fenerty) invented the wood pulp process for use in papermaking. He i ...
independently developed processes for pulping wood fibres.


Early sources of fibre

Before the industrialisation of paper production the most common fibre source was recycled fibres from used textiles, called rags. The rags were from hemp, linen and
cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...
. A process for removing printing inks from
recycled paper The recycling of paper is the process by which waste paper is turned into new paper products. It has a number of important benefits: It saves waste paper from occupying homes of people and producing methane as it breaks down. Because paper fib ...
was invented by German jurist
Justus Claproth Justus Claproth (28 December 1728 – 20 February 1805) was a German jurist and inventor of the deinking process of recycled paper. See also *German inventors and discoverers ---- __NOTOC__ This is a list of German inventors and discovere ...
in 1774. Today this method is called
deinking Deinking is the industrial process of removing printing ink from paperfibers of recycled paper to make deinked pulp. The key in the deinking process is the ability to detach ink from the fibers. This is achieved by a combination of mechanical ac ...
. It was not until the introduction of
wood pulp Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw mate ...
in 1843 that paper production was not dependent on recycled materials from ragpickers.


Etymology

The word ''paper'' is etymologically derived from
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
, which comes from the
Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...
(), the word for the plant.
Papyrus Papyrus ( ) is a material similar to thick paper that was used in ancient times as a writing surface. It was made from the pith of the papyrus plant, '' Cyperus papyrus'', a wetland sedge. ''Papyrus'' (plural: ''papyri'') can also refer to a ...
is a thick, paper-like material produced from the pith of the ' plant, which was used in ancient Egypt and other
Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western Europe, Western and Southern Europe and Anatolia, on the south by North Africa ...
cultures for
writing Writing is a medium of human communication which involves the representation of a language through a system of physically inscribed, mechanically transferred, or digitally represented symbols. Writing systems do not themselves constitute h ...
before the introduction of paper. Although the word ''paper'' is etymologically derived from ''papyrus'', the two are produced very differently and the development of the first is distinct from the development of the second. Papyrus is a lamination of natural plant fibre, while paper is manufactured from fibres whose properties have been changed by maceration.


Papermaking


Chemical pulping

To make pulp from wood, a
chemical pulping process Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw mat ...
separates lignin from
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell w ...
fibre. A cooking liquor is used to dissolve the lignin, which is then washed from the
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell w ...
; this preserves the length of the cellulose fibres. Paper made from chemical pulps are also known as
wood-free paper Wood-free paper is paper created exclusively from chemical pulp rather than mechanical pulp. Chemical pulp is normally made from pulpwood, but is not considered wood as most of the lignin is removed and separated from the cellulose fibers during ...
s (not to be confused with
tree-free paper Tree-free paper or tree-free newsprint described an alternative to wood-pulp paper by its raw material composition. It is claimed to be more eco-friendly considering the product's entire life cycle. Sources of fiber for tree-free paper includ ...
); this is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres. Chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose. There are three main chemical pulping processes: the sulfite process dates back to the 1840s and was the dominant method before the second world war. The kraft process, invented in the 1870s and first used in the 1890s, is now the most commonly practised strategy; one of its advantages is the chemical reaction with lignin produces heat, which can be used to run a generator. Most pulping operations using the kraft process are net contributors to the electricity grid or use the electricity to run an adjacent paper mill. Another advantage is that this process recovers and reuses all inorganic chemical reagents.
Soda pulping Soda pulping is a chemical process for making wood pulp with sodium hydroxide as the cooking chemical. In the ''Soda-AQ'' process, anthraquinone (AQ) may be used as a pulping additive to decrease the carbohydrate degradation. The soda process gives ...
is another specialty process used to pulp straws,
bagasse Bagasse ( ) is the dry pulpy fibrous material that remains after crushing sugarcane or sorghum stalks to extract their juice. It is used as a biofuel for the production of heat, energy, and electricity, and in the manufacture of pulp and building ...
and
hardwoods Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from ...
with high silicate content.


Mechanical pulping

There are two major mechanical pulps: thermomechanical pulp (TMP) and groundwood pulp (GW). In the TMP process, wood is chipped and then fed into steam-heated refiners, where the chips are squeezed and converted to fibres between two steel discs. In the groundwood process, debarked logs are fed into grinders where they are pressed against rotating stones to be made into fibres. Mechanical pulping does not remove the lignin, so the yield is very high, > 95%; however, lignin causes the paper thus produced to turn yellow and become brittle over time. Mechanical pulps have rather short fibres, thus producing weak paper. Although large amounts of electrical energy are required to produce mechanical pulp, it costs less than the chemical kind.


De-inked pulp

Paper recycling processes can use either chemically or mechanically produced pulp; by mixing it with water and applying mechanical action the
hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...
bonds in the paper can be broken and fibres separated again. Most recycled paper contains a proportion of virgin fibre for the sake of quality; generally speaking, de-inked pulp is of the same quality or lower than the collected paper it was made from. There are three main classifications of recycled fibre: * Mill broke or internal mill waste – This incorporates any substandard or grade-change paper made within the paper mill itself, which then goes back into the manufacturing system to be re-pulped back into paper. Such out-of-specification paper is not sold and is therefore often not classified as genuine reclaimed recycled fibre; however most paper mills have been reusing their own waste fibre for many years, long before recycling became popular. * Preconsumer waste – This is offcut and processing waste, such as guillotine trims and envelope blank waste; it is generated outside the paper mill and could potentially go to landfill, and is a genuine recycled fibre source; it includes de-inked preconsumer waste (recycled material that has been printed but did not reach its intended end use, such as waste from printers and unsold publications). * Postconsumer waste – This is fibre from paper that has been used for its intended end use and includes office waste, magazine papers and newsprint. As the vast majority of this material has been printed – either digitally or by more conventional means such as lithography or rotogravure – it will either be recycled as printed paper or go through a de-inking process first. Recycled papers can be made from 100% recycled materials or blended with virgin pulp, although they are (generally) not as strong nor as bright as papers made from the latter.


Additives

Besides the fibres, pulps may contain fillers such as
chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Ch ...
or
china clay Kaolinite ( ) is a clay mineral, with the chemical composition Al2 Si2 O5( OH)4. It is an important industrial mineral. It is a layered silicate mineral, with one tetrahedral sheet of silica () linked through oxygen atoms to one octahedra ...
, which improve its characteristics for printing or writing. Additives for sizing purposes may be mixed with it or applied to the paper web later in the manufacturing process; the purpose of such sizing is to establish the correct level of surface absorbency to suit ink or paint.


Producing paper

The
pulp Pulp may refer to: * Pulp (fruit), the inner flesh of fruit Engineering * Dissolving pulp, highly purified cellulose used in fibre and film manufacture * Pulp (paper), the fibrous material used to make paper * Molded pulp, a packaging material ...
is fed to a paper machine, where it is formed as a paper web and the water is removed from it by pressing and drying. Pressing the sheet removes the water by force. Once the water is forced from the sheet, a special kind of felt, which is not to be confused with the traditional one, is used to collect the water. When making paper by hand, a blotter sheet is used instead. Drying involves using air or heat to remove water from the paper sheets. In the earliest days of papermaking, this was done by hanging the sheets like laundry; in more modern times, various forms of heated drying mechanisms are used. On the paper machine, the most common is the steam-heated can dryer. These can reach temperatures above and are used in long sequences of more than forty cans where the heat produced by these can easily dry the paper to less than six percent moisture.


Finishing

The paper may then undergo sizing to alter its physical properties for use in various applications. Paper at this point is ''uncoated''. Coated paper has a thin layer of material such as calcium carbonate or
china clay Kaolinite ( ) is a clay mineral, with the chemical composition Al2 Si2 O5( OH)4. It is an important industrial mineral. It is a layered silicate mineral, with one tetrahedral sheet of silica () linked through oxygen atoms to one octahedra ...
applied to one or both sides in order to create a surface more suitable for high-resolution halftone screens. (Uncoated papers are rarely suitable for screens above 150 lpi.) Coated or uncoated papers may have their surfaces polished by calendering. Coated papers are divided into matte, semi-matte or silk, and gloss. Gloss papers give the highest optical density in the printed image. The paper is then fed onto reels if it is to be used on web printing presses, or cut into sheets for other printing processes or other purposes. The fibres in the paper basically run in the machine direction. Sheets are usually cut "long-grain", i.e. with the grain parallel to the longer dimension of the sheet. Continuous form paper (or continuous stationery) is cut to width with holes punched at the edges, and folded into stacks.


Paper grain

All paper produced by paper machines as the
Fourdrinier Machine A paper machine (or paper-making machine) is an industrial machine which is used in the pulp and paper industry to create paper in large quantities at high speed. Modern paper-making machines are based on the principles of the Fourdrinier Mach ...
are wove paper, i.e. the wire mesh that transports the web leaves a pattern that has the same density along the paper grain and across the grain. Textured finishes,
watermark A watermark is an identifying image or pattern in paper that appears as various shades of lightness/darkness when viewed by transmitted light (or when viewed by reflected light, atop a dark background), caused by thickness or density variations ...
s and wire patterns imitating hand-made ''laid'' paper can be created by the use of appropriate rollers in the later stages of the machine. Wove paper does not exhibit "laidlines", which are small regular lines left behind on paper when it was handmade in a mould made from rows of metal wires or bamboo. Laidlines are very close together. They run perpendicular to the "chainlines", which are further apart. Handmade paper similarly exhibits "deckle edges", or rough and feathery borders.


Applications

Paper can be produced with a wide variety of properties, depending on its intended use.


Published, written, or informational items

* For representing value:
paper money A banknote—also called a bill (North American English), paper money, or simply a note—is a type of negotiable promissory note, made by a bank or other licensed authority, payable to the bearer on demand. Banknotes were originally issued ...
,
bank note A banknote—also called a bill (North American English), paper money, or simply a note—is a type of negotiable promissory note, made by a bank or other licensed authority, payable to the bearer on demand. Banknotes were originally issued ...
,
cheque A cheque, or check (American English; see spelling differences) is a document that orders a bank (or credit union) to pay a specific amount of money from a person's account to the person in whose name the cheque has been issued. The pers ...
,
security" \n\n\nsecurity.txt is a proposed standard for websites' security information that is meant to allow security researchers to easily report security vulnerabilities. The standard prescribes a text file called \"security.txt\" in the well known locat ...
(see ''
security paper Security paper is a paper used in security printing that incorporates features that can be used to identify or authenticate a document as original, e.g., watermarks or invisible fibres in paper, or features that demonstrate tamper evidence when f ...
''),
voucher A voucher is a bond of the redeemable transaction type which is worth a certain monetary value and which may be spent only for specific reasons or on specific goods. Examples include housing, travel, and food vouchers. The term voucher is also ...
,
ticket Ticket or tickets may refer to: Slips of paper * Lottery ticket * Parking ticket, a ticket confirming that the parking fee was paid (and the time of the parking start) * Toll ticket, a slip of paper used to indicate where vehicles entered a tol ...
* For storing information:
book A book is a medium for recording information in the form of writing or images, typically composed of many pages (made of papyrus, parchment, vellum, or paper) bound together and protected by a cover. The technical term for this physi ...
, notebook, graph paper,
punched card A punched card (also punch card or punched-card) is a piece of stiff paper that holds digital data represented by the presence or absence of holes in predefined positions. Punched cards were once common in data processing applications or to di ...
, photographic paper * For published materials, publications, and reading materials: books, newspapers, magazines, posters, pamphlets, maps, signs, labels, advertisements, billboards. * For individual use:
diary A diary is a written or audiovisual record with discrete entries arranged by date reporting on what has happened over the course of a day or other period. Diaries have traditionally been handwritten but are now also often digital. A personal ...
, notebooks, writing pads, memo pads journals, planners, note to remind oneself, etc.; for temporary personal use: scratch paper * For business and professional use: copier paper, ledger paper, typing paper, computer printer paper. Specialized paper for forms and documents such as invoices, receipts, tickets, vouchers, bills, contracts, official forms, agreements. * For
communication Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inqui ...
: between individuals and/or groups of people:
letter Letter, letters, or literature may refer to: Characters typeface * Letter (alphabet), a character representing one or more of the sounds used in speech; any of the symbols of an alphabet. * Letterform, the graphic form of a letter of the alphabe ...
, post cards, airmail, telegrams, newsprint,
card stock Card stock, also called cover stock and pasteboard, is paper that is thicker and more durable than normal writing and printing paper, but thinner and more flexible than other forms of paperboard. Card stock is often used for business cards, ...
* For organizing and sending documents: envelopes, file folders, packaging, pocket folders, partition folders. * For artistic works and uses; drawing paper, pastels, water color paintings,
sketch pads Sketch or Sketches may refer to: * Sketch (drawing), a rapidly executed freehand drawing that is not usually intended as a finished work Arts, entertainment and media * Sketch comedy, a series of short scenes or vignettes called sketches Fi ...
,
charcoal drawings Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, cal ...
, * For special printed items using more elegant forms of paper; stationery, parchment,


Packaging and industrial uses

* For packaging:
corrugated box Corrugated box design is the process of matching design factors for corrugated fiberboard boxes with the functional physical, processing and end-use requirements. Packaging engineers work to meet the performance requirements of a box while control ...
,
paper bag A paper bag is a bag made of paper, usually kraft paper. Paper bags can be made either with virgin or recycled fibres to meet customers’ demands. Paper bags are commonly used as shopping carrier bags and for packaging of some consumer go ...
,
envelope An envelope is a common packaging item, usually made of thin, flat material. It is designed to contain a flat object, such as a letter or card. Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a sh ...
,
wrapping paper Gift wrapping is the act of enclosing a gift in some sort of material. Wrapping paper is a kind of paper designed for gift wrapping. An alternative to gift wrapping is using a gift box or bag. A wrapped or boxed gift may be held closed with ri ...
,
paper string Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...
* For cleaning:
toilet paper Toilet paper (sometimes called toilet tissue or bathroom tissue) is a tissue paper product primarily used to clean the anus and surrounding anal region of feces after defecation, and to clean the perineal area and external genitalia of ur ...
,
paper towel A paper towel is an absorbent, disposable towel made from paper. In Britain, paper towels for kitchen use are also known as kitchen rolls, kitchen paper, or kitchen towels. For home use, paper towels are usually sold in a roll of perforated shee ...
s,
facial tissue Facial tissue and paper handkerchief refers to a class of soft, absorbent, disposable papers that are suitable for use on the face. They are disposable alternatives for cloth handkerchiefs. The terms are commonly used to refer to the type of pap ...
. * For food utensils and containers:
wax paper Waxed paper (also wax paper, waxpaper, or paraffin paper) is paper that has been made moisture-proof and grease-proof through the application of wax. The practice of oiling parchment or paper in order to make it semi-translucent or moisture-pro ...
,
paper plate Disposable tableware includes all disposable tableware like * disposable cups made of paper, plastic, coated paper, * plates *tablecloths, * placemats *plastic cutlery, *paper napkins, etc. These products are prevalent in fast food restaurant ...
s and paper cups,
beverage cartons A carton is a box or container usually made of liquid packaging board, paperboard and sometimes of corrugated fiberboard. Many types of cartons are used in packaging. Sometimes a carton is also called a box. Types of cartons Folding cart ...
, tea bags, condiments, food packaging, coffee filters, cupcake cups. * For construction:
papier-mâché upright=1.3, Mardi Gras papier-mâché masks, Haiti upright=1.3, Papier-mâché Catrinas, traditional figures for day of the dead celebrations in Mexico Papier-mâché (, ; , literally "chewed paper") is a composite material consisting of p ...
,
origami paper Origami paper is used to fold ''origami'', the art of paper folding. The only real requirement of the folding medium is that it must be able to hold a crease, but should ideally also be thinner than regular paper for convenience when multiple fol ...
,
paper plane A paper plane (also known as a paper airplane in American English or paper aeroplane in British English) is a toy aircraft, usually a glider made out of single folded sheet of paper or paperboard. A simple nose-heavy paper plane, thrown like ...
s,
quilling Quilling is an art form that involves the use of strips of paper that are rolled, shaped, and glued together to create decorative designs. The paper is rolled, looped, curled, twisted, and otherwise manipulated to create shapes that make up d ...
,
paper honeycomb Honeycomb structures are natural or man-made structures that have the geometry of a honeycomb to allow the minimization of the amount of used material to reach minimal weight and minimal material cost. The geometry of honeycomb structures can ...
,
sandpaper upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)). Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...
, used as a core material in
composite material A composite material (also called a composition material or shortened to composite, which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or ...
s,
paper engineering Paper engineering is a branch of engineering that deals with the usage of physical science (e.g. chemistry and physics) and life sciences (e.g. biology and biochemistry) in conjunction with mathematics as applied to the converting of raw materia ...
,
construction paper Construction paper, also known as sugar paper, is coloured cardstock paper. The texture is slightly rough, and the surface is unfinished. Due to the source material, mainly wood pulp, small particles are visible on the paper's surface. It is used f ...
,
paper yarn Paper yarn is the yarn made from paper strips chiefly with Pulp (paper), wood pulp cut into strips and then twisted to form a yarn. Germany invented Paper yarn in the late 19th century, although paper has been used in textiles in Japan for centurie ...
, and
paper clothing Paper clothing describes garments and accessories made from paper or paper substitutes. The earliest known paper clothing was made by Japanese craftspeople in the 10th century BCE, usually from washi paper, and called ''kamiko''. ''Kamiko'' becam ...
* For other uses:
emery paper Emery paper is a type of abrasive paper or sandpaper, that can be used to abrade (remove material from) surfaces or mechanically finish a surface. Operations include deburring, polishing, paint removal, corrosion removal, sizing, etc. This i ...
,
blotting paper Blotting paper, called bibulous paper, is a highly absorbent type of paper or other material. It is used to absorb an excess of liquid substances (such as ink or oil) from the surface of writing paper or objects. Blotting paper referred to as ...
,
litmus paper Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. It is a purple dye that is extracte ...
,
universal indicator __FORCETOC__ A universal indicator is a pH indicator made of a solution of several compounds that exhibits several smooth colour changes over a wide range pH values to indicate the acidity or alkalinity of solutions. Although there are several ...
paper,
paper chromatography Paper chromatography is an analytical method used to separate coloured chemicals or substances. It is now primarily used as a teaching tool, having been replaced in the laboratory by other chromatography methods such as thin-layer chromatography ...
,
electrical insulation paper Electrical insulation papers are paper types that are used as electrical insulation in many applications due to pure cellulose having outstanding electrical properties. Cellulose is a good insulator and is also polar, having a dielectric constan ...
(see also fishpaper),
filter paper Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases. The raw materials are different Pulp (paper), paper pulps. The pulp may be made from soft ...
,
wallpaper Wallpaper is a material used in interior decoration to decorate the interior walls of domestic and public buildings. It is usually sold in rolls and is applied onto a wall using wallpaper paste. Wallpapers can come plain as "lining paper" (so ...
It is estimated that paper-based storage solutions captured 0.33% of the total in 1986 and only 0.007% in 2007, even though in absolute terms the world's capacity to store information on paper increased from 8.7 to 19.4
petabyte The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable uni ...
s."The World's Technological Capacity to Store, Communicate, and Compute Information"
, especiall
Supporting online material
, Martin Hilbert and Priscila López (2011),
Science Science is a systematic endeavor that Scientific method, builds and organizes knowledge in the form of Testability, testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earli ...
, 332(6025), 60–65; free access to the article through here: martinhilbert.net/WorldInfoCapacity.html
It is estimated that in 1986 paper-based postal letters represented less than 0.05% of the world's telecommunication capacity, with sharply decreasing tendency after the massive introduction of digital technologies. Paper has a major role in the visual arts. It is used by itself to form two- and three-dimensional shapes and collages. It has also evolved to being a structural material used in furniture design.
Watercolor paper Watercolor paper or watercolour paper is paper or substrate onto which an artist applies watercolor paints, pigments or dyes. "The term “colour” is inappropriately given by common usage to material substances which convey a sense of colour t ...
has a long history of production and use.


Types, thickness and weight

The thickness of paper is often measured by caliper, which is typically given in thousandths of an inch in the United States and in micrometres (µm) in the rest of the world. Paper may be between thick. Paper is often characterized by weight. In the United States, the weight is the weight of a ream (bundle of 500 sheets) of varying "basic sizes" before the paper is cut into the size it is sold to end customers. For example, a ream of 20 lb, paper weighs 5 pounds because it has been cut from larger sheets into four pieces. In the United States, printing paper is generally 20 lb, 24 lb, 28 lb, or 32 lb at most.
Cover stock Card stock, also called cover stock and pasteboard, is paper that is thicker and more durable than normal writing and printing paper, but thinner and more flexible than other forms of paperboard. Card stock is often used for business cards, p ...
is generally 68 lb, and 110 lb or more is considered
card stock Card stock, also called cover stock and pasteboard, is paper that is thicker and more durable than normal writing and printing paper, but thinner and more flexible than other forms of paperboard. Card stock is often used for business cards, ...
. In Europe and other regions using the ISO 216 paper-sizing system, the weight is expressed in grams per square metre (g/m2 or usually gsm) of the paper. Printing paper is generally between 60 gsm and 120 gsm. Anything heavier than 160 gsm is considered card. The weight of a ream therefore depends on the dimensions of the paper and its thickness. Most commercial paper sold in North America is cut to standard
paper size Paper size standards govern the size of sheets of paper used as writing paper, stationery, cards, and for some printed documents. The ISO 216 standard, which includes the commonly used A4 size, is the international standard for paper size. I ...
s based on customary units and is defined by the length and width of a sheet of paper. The ISO 216 system used in most other countries is based on the surface area of a sheet of paper, not on a sheet's width and length. It was first adopted in Germany in 1922 and generally spread as nations adopted the metric system. The largest standard size paper is A0 (A zero), measuring one square metre (approx. 1189 × 841 mm). A1 is half the size of a sheet of A0 (i.e., 594 mm × 841 mm), such that two sheets of A1 placed side by side are equal to one sheet of A0. A2 is half the size of a sheet of A1, and so forth. Common sizes used in the office and the home are A4 and A3 (A3 is the size of two A4 sheets). The
density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...
of paper ranges from for tissue paper to for some specialty paper. Printing paper is about . Paper may be classified into seven categories: * ''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 paper Ingres paper is a type of drawing paper. It is a laid finish paper of light to medium weight, and it is not as strong or as durable as Bristol paper. Laid finish refers to the imprint of regular screen pattern of a papermaker's mould. Ingres is ...
s,
Japanese paper is traditional Japanese paper. The term is used to describe paper that uses local fiber, processed by hand and made in the traditional manner. ''Washi'' is made using fibers from the inner bark of the gampi tree, the mitsumata shrub ('' ...
and tissues, all characterized by lack of grain direction. * ''Specialty papers'' including cigarette paper, toilet tissue, and other industrial papers. Some paper types include: *
Bank paper Bank paper is a thin strong writing paper of less than 50g/m2. It is commonly used for typewriting and correspondence. The term is also used for securities that are issued by banks, instead of governments. See also commercial paper, securities iss ...
*
Banana paper Banana paper is a type of paper created from banana plant bark or banana peel fibers. Banana paper has a lower density, higher stiffness, higher disposability, higher renewability, and higher tensile strength compared to traditional paper. These ...
*
Bond paper Bond paper is a high-quality durable writing paper similar to bank paper but having a weight greater than 50 g/m2. The most common weights are 60 g/m2 (16 lb), 75 g/m2 (20 lb) and 90 g/m2 (24 lb). The name comes from ...
*
Book paper A book paper (or publishing paper) is a paper that is designed specifically for the publication of printed books. Traditionally, book papers are off-white or low-white papers (easier to read), are opaque to minimise the show-through of text fro ...
* Coated paper: glossy and matte surface * Construction paper/sugar paper * Cotton paper *
Fish paper Vulcanized fibre or red fibre is a laminated plastic composed of only cellulose. The material is a tough, resilient, hornlike material that is lighter than aluminium, tougher than leather, and stiffer than most thermoplastics. The newer wood-lami ...
(
vulcanized Vulcanization (British: Vulcanisation) is a range of processes for hardening rubbers. The term originally referred exclusively to the treatment of natural rubber with sulfur, which remains the most common practice. It has also grown to inclu ...
fibres for electrical insulation) *
Inkjet paper Inkjet paper is a special fine paper designed for inkjet printers, typically classified by its weight, brightness and smoothness, and sometimes by its opacity. Manufacture Some inkjet papers are made from high quality deinked pulp or chemical ...
*
Kraft paper Kraft paper or kraft 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 packag ...
*
Laid paper Laid paper is a type of paper having a ribbed texture imparted by the manufacturing process. In the pre-mechanical period of European papermaking (from the 12th century into the 19th century), laid paper was the predominant kind of paper produced. ...
*
Leather paper Parchment is a writing material made from specially prepared untanned skins of animals—primarily sheep, calves, and goats. It has been used as a writing medium for over two millennia. Vellum is a finer quality parchment made from the skins of ...
*
Mummy paper Mummy paper is paper that is claimed to be made from the linen wrappings and other fibers (e.g. papyrus) from Egyptian mummies imported to America circa 1855. The existence of this paper has not been conclusively confirmed, but it has been widel ...
*
Oak tag paper An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...
*
Sandpaper upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)). Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...
*
Troublewit Troublewit is a specially pleated paper used for entertainment purposes. The paper is used to form various items, such as hats, fans and umbrellas by stage entertainers and illusionists. Its origins go back at least to the 17th Century. The metho ...
, specially pleated paper *
Tyvek paper Tyvek () is a brand of synthetic flashspun high-density polyethylene fibers. The name "Tyvek" is a registered trademark of the American multinational chemical company DuPont, which discovered and commercialized Tyvek in the late 1950s and earl ...
*
Wallpaper Wallpaper is a material used in interior decoration to decorate the interior walls of domestic and public buildings. It is usually sold in rolls and is applied onto a wall using wallpaper paste. Wallpapers can come plain as "lining paper" (so ...
*
Washi is traditional Japanese paper. The term is used to describe paper that uses local fiber, processed by hand and made in the traditional manner. ''Washi'' is made using fibers from the inner bark of the gampi tree, the mitsumata shrub (''E ...
*
Waterproof paper Waterproof paper uses special coatings (plastic-coated paper) and fibers to enhance durability, dimensional stability, tear resistance and resistance to changing shape or texture when exposed to water. The paper has applications for wet or damp ...
*
Wax paper Waxed paper (also wax paper, waxpaper, or paraffin paper) is paper that has been made moisture-proof and grease-proof through the application of wax. The practice of oiling parchment or paper in order to make it semi-translucent or moisture-pro ...
*
Wove paper Wove paper is a type of paper first created centuries ago in the Orient, and subsequently introduced to England, Europe and the American colonies in the mid-eighteenth century. Hand-made wove paper was first produced by using a wooden mould that ...
*
Xuan paper Xuan paper (''xuanzhi'' ), or Shuen paper or rice paper, is a kind of paper originating in ancient China used for writing and painting. Xuan paper is renowned for being soft and fine textured, suitable for conveying the artistic expression of ...


Paper stability

Much of the early paper made from wood pulp contained significant amounts of alum, a variety of aluminium sulfate salt that is significantly
acidic In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a ...
. Alum was added to paper to assist in sizing, making it somewhat water resistant so that
inks Ink is a gel, sol, or solution that contains at least one colorant, such as a dye or pigment, and is used to color a surface to produce an image, text, or design. Ink is used for drawing or writing with a pen, brush, reed pen, or quill. Thicke ...
did not "run" or spread uncontrollably. Early papermakers did not realize that the alum they added liberally to cure almost every problem encountered in making their product would be eventually detrimental. The
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell w ...
fibres that make up paper are hydrolyzed by acid, and the presence of alum eventually degrades the fibres until the
acidic paper Acidic paper is paper that had some acidic substances used during the manufacture process. This type of paper, widely used since the mid-nineteenth century, turns yellow in a short time and becomes extremely brittle, which causes huge losses in lib ...
disintegrates in a process known as "
slow fire A slow fire is a term used in library and information science to describe paper embrittlement resulting from acid decay. The term is taken from the title of Terry Sanders's 1987 film ''Slow Fires: On the preservation of the human record.'' Solut ...
". Documents written on
rag paper Rag, rags, RAG or The Rag may refer to: Common uses * Rag, a piece of old cloth * Rags, tattered clothes * Rag (newspaper), a publication engaging in tabloid journalism * Rag paper, or cotton paper Arts and entertainment Film * ''Rags'' (1915 ...
are significantly more stable. The use of non-acidic additives to make paper is becoming more prevalent, and the stability of these papers is less of an issue. Paper made from
mechanical pulp Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw mate ...
contains significant amounts of lignin, a major component in wood. In the presence of light and oxygen, lignin reacts to give yellow materials, which is why newsprint and other mechanical paper yellows with age. Paper made from bleached kraft or sulfite pulps does not contain significant amounts of lignin and is therefore better suited for books, documents and other applications where whiteness of the paper is essential. Paper made from wood pulp is not necessarily less durable than a rag paper. The aging behaviour of a paper is determined by its manufacture, not the original source of the fibres. Furthermore, tests sponsored by the Library of Congress prove that all paper is at risk of acid decay, because cellulose itself produces formic, acetic, lactic and oxalic acids. Mechanical pulping yields almost a tonne of pulp per tonne of dry wood used, which is why mechanical pulps are sometimes referred to as "high yield" pulps. With almost twice the yield as chemical pulping, mechanical pulps is often cheaper. Mass-market paperback books and newspapers tend to use mechanical papers. Book publishers tend to use acid-free paper, made from fully bleached chemical pulps for
hardback A hardcover, hard cover, or hardback (also known as hardbound, and sometimes as case-bound) book is one bound with rigid protective covers (typically of binder's board or heavy paperboard covered with buckram or other cloth, heavy paper, or occa ...
and trade paperback books.


Environmental impact

The production and use of paper has a number of adverse effects on the environment. Worldwide consumption of paper has risen by 400% in the past 40 years leading to increase in
deforestation Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated ...
, with 35% of harvested trees being used for paper manufacture. Most paper companies also plant trees to help regrow forests. Logging of
old growth forest An old-growth forestalso termed primary forest, virgin forest, late seral forest, primeval forest, or first-growth forestis a forest that has attained great age without significant disturbance, and thereby exhibits unique ecological feature ...
s accounts for less than 10% of wood pulp, but is one of the most controversial issues. Paper waste accounts for up to 40% of total waste produced in the United States each year, which adds up to 71.6 million tons of paper waste per year in the United States alone. The average office worker in the US prints 31 pages every day. Americans also use in the order of 16 billion paper cups per year. Conventional bleaching of wood pulp using elemental chlorine produces and releases into the environment large amounts of chlorinated organic compounds, including chlorinated dioxins.Pdf
Dioxins are recognized as a persistent environmental pollutant, regulated internationally by the Stockholm Convention on Persistent Organic Pollutants. Dioxins are highly toxic, and health effects on humans include reproductive, developmental, immune and hormonal problems. They are known to be carcinogenic. Over 90% of human exposure is through food, primarily meat, dairy, fish and shellfish, as dioxins accumulate in the food chain in the fatty tissue of animals. The paper pulp and print industries emitted together about 1% of world Greenhouse-gas emissions in 2010 and about 0.9% in 2012, but less than screens: digital technologies emitted approximately 4% of world Greenhouse-gas emissions in the year 2019 and the number can be two times larger by 2025.


Future

Some manufacturers have started using a new, significantly more environmentally friendly alternative to expanded plastic packaging. Made out of paper, and known commercially as PaperFoam, the new packaging has mechanical properties very similar to those of some expanded plastic packaging, but is biodegradable and can also be recycled with ordinary paper. With increasing environmental concerns about synthetic coatings (such as
PFOA Perfluorooctanoic acid (PFOA; conjugate base perfluorooctanoate; also known colloquially as C8, for its 8 carbon chain structure) is a perfluorinated carboxylic acid produced and used worldwide as an industrial surfactant in chemical processes a ...
) and the higher prices of hydrocarbon based petrochemicals, there is a focus on
zein Zein is a class of prolamine protein found in maize (corn). It is usually manufactured as a powder from corn gluten meal. Zein is one of the best understood plant proteins.Momany, Frank A.; Sessa, David J.; Lawton, John C.; Selling, Gordon W.; H ...
(corn protein) as a coating for paper in high grease applications such as popcorn bags. Also, synthetics such as
Tyvek Tyvek () is a brand of synthetic flashspun high-density polyethylene fibers. The name "Tyvek" is a registered trademark of the American multinational chemical company DuPont, which discovered and commercialized Tyvek in the late 1950s and early ...
and Teslin have been introduced as printing media as a more durable material than paper.


See also


Citations


General references

* * * "Document Doubles" i
ARCHIVED – Introduction – Detecting the Truth. Fakes, Forgeries and Trickery – Library and Archives Canada
a virtual museum exhibition at Library and Archives Canada


Further reading

*
"Paper Brightness, Whiteness & Shade: Definitions and Differences"
by David Rogers (June 26, 2015)


External links


Technical Association of the Pulp and Paper Industry
(
TAPPI TAPPI is a registered not-for-profit, international Non-Governmental Organization of about 14,000 member engineers, scientists, managers, academics and others involved in the areas of pulp, and paper. In addition to pulp and paper, the TAPPI memb ...
) official website * The Arnold Yates Paper collection at University of Maryland Libraries
"How is paper made?"
at The
Straight Dope "The Straight Dope" was a question-and-answer newspaper column written under the pseudonym Cecil Adams. Contributions were made by multiple authors, and it was illustrated (also pseudonymously) by Slug Signorino. It was first published in 1973 i ...
, 22 November 2005
Thirteen-minute video on modern paper production system
from
Sappi Sappi Limited, originally incorporated as ''South African Pulp and Paper Industries Limited'' in 1936, is a South African pulp and paper company with global operations. Products and operation South African Pulp and Paper Industries Limite ...
{{Authority control Papermaking Chinese inventions