Paper and paper making (2023)

by Chris Woodford. Last updated: October 28, 2022.

If you weren't glued to yourcomputer screen right now, you might be reading thisarticle on paper from a book; for about 2000 years until theappearance of the World Wide Web, virtually all written informationwas distributed in printed form. The idea of getting information frominked-up sheets of paper is starting to seem a little bitold-fashioned, but that doesn't mean we're going to ditch paperanytime soon. People have been predicting the arrival of the"paperless society" for decades and it still seems no nearer; ifanything, we use more paper now than ever before—and not just forprinting. Huge amounts of paper and card are still used for productpackaging, in towels and diapers, and in a wide variety of buildingmaterials. It's probably no exaggeration to say that paper is theworld's favorite material. Let's take a closer look and what it isand how it's made!

Photo: Even in the computer age, we still use vast quantities of paper. Thisphoto could have been taken yesterday; in fact, it was shot in 1943 at the huge Southland Paper Mills near Lufkin, Texas, and shows newsprint (paper for printing newspapers) madefrom wood pulp using the Kraft process. Photo by John Vachon for theOffice of War Information, courtesy of US Library of Congress.

What is paper?

Paper is a dried, compressed mat of plant fibers—nothing more, nothing less. It's a bitlike clothing you can write on. No, really! Clothes are madeby weaving together yarns such as cotton and wool spun from naturalfibers. Paper is more like the fabric we call felt, made without theweaving stage by pressing together cellulose fibers extracted fromplants and trees so they knit and fuse to form a strong, solid, butstill very flexible mat.

How is paper made?

Most paper pulp is made from trees (mainly fast-growing, evergreen conifers), though itcan also be made from bamboo, cotton, hemp, jute, and a wide range ofother plant materials. Smooth papers used for magazines or packagingoften have materials such as china clay added so they print with amore colorful, glossy finish.

Photo: Paper can be made from lots of different materials. 1) Trees felled for papermaking. Although many different tree species can be used, hardwoods provide the bulk of the fibers in paper,while softwood fibers are used more for strength. 2) Stacks of hay waiting to be made into low-gradepaper in Hebei Province, China. China and the United States are the world's leading paper makers, each producing close to 80 million tons of paper per year. Photo by Simon Tsuo courtesy of US DOE/NREL (US Department of Energy/National Renewable Energy Laboratory).

Here's the basic idea: you take a plant, bash itabout to release the fibers, and mix it with water to get a soggysuspension of fibers called pulp (or stock). Then spread thepulp out on a wire mesh so the fibers knit and bond together, squeezethe water away, dry out your pulp, and what you've got is paper!

Paper is really easy to make by hand (try it for yourself) but people use so much of it that most is nowmade by giant machines. Whichever method is used, there areessentially two stages: getting the pulp ready and then forming itand drying it into finished sheets or rolls.

Papermaking materials

As you can see from the chart below, recycled paper (green line) has long since overtaken woodpulp (brown line) as the main source of raw materials. In Europe (EU plus Norway, Switzerland, and UK), about 71 percent of paper was recycled in 2021, compared to just 40 percent in 1991. Even so, very large amounts of wood are still consumed to make paper: roughly 152 million cubic meters of wood are used by the European paper industry each year (26.4 percent hardwood and 73.6 percent softwood), but only about 40 million cubic meters of that (less than a third) finds its way into papermills as usable pulp.[Source: Key Statistics: European Pulp and Paper Industry 2021, Confederation of European Paper Industries (CEPI), 2022.]

Chart based on statistics from Key Statistics: European Pulp and Paper Industry 2021, Confederation of European Paper Industries (CEPI), 2022.

Papermaking by hand

The raw plant material is placed in a large vessel filled with water and literallybeaten to a pulp to make a thick suspension of fibers calledhalf-stuff. This is formed into sheets of paper using a verybasic frame made of two parts: a metal mesh called a mold thatsits inside a wooden frame known as a deckle (a bit like apicture frame). The mold and deckle are dipped into the half stuffand gently agitated so an even coating forms on top, with most of thewater (and some of the pulp) draining through. The deckle is thenremoved from the mold and the soggy mat of paper is placed on a sheetof felt. This process is repeated to make a number of interleavedsheets of paper and felt, which are then placed inside ascrew-operated press and squeezed under immense pressure to squashout virtually all the remaining water. After that, the sheets of paperare taken out and hung up to dry.

Photo: Look really closely at almost any ordinary paper and you'll see just how fibrousit is! The photo on the right is a closeup of the one on the left. It might look like a pile of foldedfluffy bathroom towels, but really it's sheets of paper! This is 100 percent recycled Evolve paper made by M-real.

Papermaking by machine

Although some expensive papers are still crafted by hand, most are churned outquickly, efficiently, and automatically by gigantic machines. Pulp is preparedfor papermaking machines either mechanically or chemically. Themechanical method (generally used to make lower-grades of paper) iscalled the groundwood process, because the pulpwas originally made by using huge stones to grind up logs. Nowadays, pulp isprepared by giant machines that cut, wash, chop, beat, and blendwood, rags, or other raw materials into a soggy mass of fibers. Inthe chemical method, known as the Kraft process (from theGerman word for "strength," because it produces strong paper),plant materials are boiled up in strong alkalis such as sodium sulfide orsodium hydroxide to produce fibers. At this point,loading materials (surface coatings such as clays), dyes (to makecolored paper), and sizes (to strengthen and waterproof and preventinks from spreading) can be added to the mixture to change theproperties of the finished paper (sometimes they're added later).

Photo: A small papermaking machine from the early 20th century. Photo bycourtesy of National Institute of Standards and Technology (NIST) Photographic Collection.

Once the pulp has been prepared, it's turned into paper by an enormous roller machine.The best known type of papermaking machine is called a Fourdriniermachine (named for the two English brothers who invented it atthe start of the 19th century), though there are alternatives (including thecylinder machine developed a few years afterward by John Dickinson).Wet pulp enters the machine from a trough called a headbox atone end and is spread over a moving, wire-mesh conveyor belt. Thebelt is shaken, sucked, and blown to remove water from the mat offibers, before a watermark, texture, or other finish is pressed intoit by a patterned roller called the dandy roll. The paper isthen pressed further and fully dried, looping again and again around a series of rollers, before getting its final, verysmooth pressing by large, heavy, steel rollers called calenders.The finished paper emerges as webs (very large sheets) or rolls (forprinting things like newspapers and magazines). The biggestFourdrinier machines produce paper at an astonishing rate of over 60km/h (40 mph)!

How does a Fourdrinier machine work?

Fourdrinier machines are large and complex, but I've simplified the process greatly and color-coded it so it's easier to understand. From wet pulp to finished roll, the paper passes through five key stages: it starts off in a large vat called the headbox (gray); begins to form into paper on the Fourdrinier table (blue); is pressed and dried by felt rollers (green); is further dried, shaped, and smoothed in the dryer (red); and is finally pressed and rolled into finished shape by the calenders (purple). The left side of the machine (as I've drawn it) is called the wet end; the right side is the dry end.

Photo: A detail of some of the rollers in a Fourdrinier machine. Photo by Russell Lee for theOffice of War Information, courtesy of US Library of Congress.

In a bit more detail:

1. Headbox: The soggy wet mass of pulp starts off here. It could be a mixture of wood pulp and recycled paper fibers.
2. Mesh: Sometimes called the Fourdrinier table or wire, this is where most of the water from the pulp is removed and the paperslowly starts to form.
3. Suction boxes: While some of the water simply drips through the mesh, more is removed by suction boxes (a bit like box-shaped vacuum cleaners designed to suck up water).
4. Dandy roll: This large roller puts a watermark, pattern, or texture on the paper.
5. Felt belt: The forming paper runs over a rotating felt belt that mops away further moisture.
6. Dryer: The paper loops back and forth over more felt rollers and heated dryers.
7. Calenders: The rollers at the very end smooth the paper so it's of completely uniform thickness.
8. Paper roll: The paper is all finished and ready to use.

Photo: From logs to rolls of paper via wood pulp and the whistling wheels of a Fourdinier machine. Historic photos by Jack Delano and others, U.S. Farm Security Administration/Office of War Information, courtesy ofUS Library of Congress.

Who invented paper and papermaking?

• 3000 BCE: Ancient Egyptians begin writing on papyrus, made from rushes growing on the banks of the Nile River.It's the first lightweight, portable writing surface.
• 105 CE: Chinese Ts'ai Lun (c.50–121 CE; also written Cai Lun) invents paper based on tree bark for the Emperor of China. Papermaking technology gradually spreads throughout Asia.
• 1100s: The Moors introduce papermaking technology to North Africa and Spain, from where it passes to the rest of Europe. Their paper is made from hemp and linen.
• 1450s: German Johannes Gutenberg (c.1400–1468) invents movable metal type and themodern printing press, and prints around 180 copies of his famous Gutenberg Bible. Thisinvention greatly increases the demand for paper.
• 1790s: Papermaking machines are invented by Frenchman Nicholas Louis Robert (1761–1828), then improved by British brothersHenry Fourdrinier (1766–1854) and Sealy Fourdrinier(1774–1847) around 1803. (The National Portrait Gallery hasa painting of the Fourdrinier family.)
• 1804: Englishman Andrew Wilson produces the first book on machine-made paper. Wilson is a London-based printer employed by Charles Mahon, 3rd Earl of Stanhope, inventor of the first iron printing press (the Stanhope press).
• 1809: Several years after the Fourdiniers, Englishman John Dickinson (1782–1869) invents and patents an alternative papermaking apparatus called the cylinder machine.(You can see a great model of Dickinson's 1809 machine on theScience and Society Picture Library website.)
• 1840: The Groundwood method of making wood pulp is developed in Germany.
• 1883: German inventor Karl Dahl develops a chemical method for making strong paper pulp called the Kraft ("strength") process.
• 1890: US-company Scott Paper of Philadelphia, Pennsylvania produces the first paper toilet roll; in 1907, it develops paper bathroom tissues for improved public hygiene. In 1931, Scott produces the first paper towels, ScottTowels, and sells them in grocery stores.

Find out more

On this website

• Inkjet printers
• Printing

On other sites

• The Environmental Impact of Paper Production: Planet Ark has a good graphic and some useful facts and figures. Archived via the Wayback machine.
• Paper: Shocking statistics: How much paper can you get from a tree? How much do people use on average each year? Lots of statistics like that on this handy page. [Archived via the Wayback Machine.]
• Environmental Paper Network: A group of organizations working to reduce the impact of papermaking on our planet (and particularly on forests).

Books

For older readers

• Paper: Paging Through History by Mark Kurlansky. W.W. Norton, 2017. A sweeping history of paper and papermaking.
• Papermaking: the history and technique of an ancient craft by Dard Hunter, Courier Dover Publications, 1978. Originally produced in the 1940s, this classic book is still available today.
• Paper by Jeanette Bakker. Murdoch Books, 2006. A brief introduction to paper and its history, followed by a guide to making your own paper, and lots of craft projects you can use it for.

For younger readers

• The Story Behind Paper by Barbara A. Somervill. Raintree, 2012. A 32-page introduction for ages 6–8.
• Papermaking (Step-by-step) by David Watson. Search Press, 2008. Another short (32-page) guide for ages 6–8, based around simple activities. It opens with a history of paper, followed by nine easy-to-make paper-based projects, from birthday cards and picture frames to string books and lampshades.

Articles

• The Circular Economy of Recycled Paper by Christopher F. Schuetze. The New York Times, November 18, 2014. Is recycling the future of paper production?
• Is digital really greener than paper? by Alison Moodie, The Guardian, 24 February 2014. The paper industry is challenging assumptions that email and other forms of digital technology are automatically better for the environment.
• Can a Papermaker Help to Save Civilization? by Mark Levine, The New York Times, 17 February 2012. A look at the life and work of Tim Barrett.
• Burnham artist makes paper from organic materials: BBC News, 21 July 2010. How Charles Bran learned to make paper from environmental materials such as leaves and seaweed.
• China's recycling 'saves forests': BBC News, 13 July 2007. Extensive paper recycling in China is helping to save the world's forests, though much of the paper is imported from the US, Japan, and Europe and is shipped a considerable distance.