Why Do Pages of Books and Newspapers Turn Yellow Over Time?


It is generally thought that paper was invented
around 100 BC in China. Originally made from wet hemp that was, then,
beaten to a pulp, tree bark, bamboo, and other plant fibers were eventually used. Paper soon spread across Asia, first only
being used for official and important documents, but as the process became more efficient and
cheaper, it became far more common. Paper first arrived in Europe likely around
the 11th century. Historians believe the oldest known paper
document from the “Christian West” is the Missal of Silos from Spain, which is essentially
a book containing texts to be read during Mass. This paper was made out of a form of linen. While paper, books, and printing would evolve
throughout the next eight hundred years, with the Gutenberg printing press coming in the
mid-15th century, paper was normally made out of linen, rags, cotton, or other plant
fibers. It wouldn’t be until the mid-19th century
when paper was made out of wood fiber. So what changed? In 1844, two individuals invented the wood
paper-making process. On one end of the Atlantic Ocean was Canadian
inventor Charles Fenerty. Growing up, his family owned a series of lumber
mills in Nova Scotia. Knowing the durability, cheapness, and availability
of wood, he realized it could be a good substitute for the much more expensive cotton used in
paper. He experimented with wood pulp and on October
26, 1844, he sent his wood pulp paper to Halifax’s top newspaper, The Acadian Recorder, with
a note touting the durability and cost-effective spruce wood paper. Within weeks, the Recorder used Fenerty’s
wood pulp paper. At the same time, German binder and weaver
Friedrich Gottlob Keller was working on a wood-cutting machine when he discovered the
same thing as Fenerty – that wood pulp could act as a cheaper paper than cotton. He produced a sample and, in 1845, received
a German patent for it. In fact, some historians credit Keller for
the invention more than Fenerty simply due to the fact that he received a patent and
the Canadian did not. Within thirty years, wood pulp paper was all
the rage on both sides of the pond. While wood pulp paper was cheaper and just
as durable as cotton or other linen papers, there were drawbacks. Most significantly, wood pulp paper is much
more prone to being effected by oxygen and sunlight. Wood is primarily made up of two polymer substances
– cellulose and lignin. Cellulose is the most abundant organic material
in nature. It is also technically colorless and reflects
light extremely well rather than absorbs it (which makes it opaque); therefore, humans
see cellulose as white. However, cellulose is also somewhat susceptible
to oxidation, although not nearly as much as lignin. Oxidation causes a loss of electron(s) and
weakens the material. In the case of cellulose, this can result
in some light being absorbed, making the material (in this case, wood pulp) appear duller and
less white (some describe it as “warmer”), but this isn’t what causes the bulk of the
yellowing in aged paper. Lignin is the other prominent substance found
in paper, newspaper in particular. Lignin is a compound found in wood that actually
makes the wood stronger and harder. In fact, according to Dr. Hou-Min Chang of
N.C. State University in Raleigh, “Without lignin,
a tree could only grow to about 6 ft. tall.” Essentially, lignin functions as something
of a “glue,” more firmly binding the cellulose fibers, helping make the tree much stiffer
and able to stand taller than they otherwise would, as well able to withstand external
pressures like wind. Lignin is a dark color naturally (think brown-paper
bags or brown cardboard boxes, where much of the lignin is left in for added strength,
while also resulting in the bags/boxes being cheaper due to less processing needed in their
creation). Lignin is also highly susceptible to oxidation. Exposure to oxygen (especially when combined
with sunlight) alters the molecular structure of lignin, causing a change in how the compound
absorbs and reflects light, resulting in the substance containing oxidized lignin turning
a yellow-brown color in the human visual spectrum. Since the paper used in newspapers tends to
be made with a less intensive and more cost-efficient process (since a lot of the wood pulp paper
is needed), there tends to be significantly more lignin in newspapers than in, say, paper
made for books, where a bleaching process is used to remove much of the lignin. The net result is that, as newspapers get
older and are exposed to more oxygen, they turn a yellowish-brown color relatively quickly. As for books, since the paper used tends to
be higher grade (among other things, meaning more lignin is removed along with a much more
intensive bleaching process), the discolorization doesn’t happen as quickly. However, the chemicals used in the bleaching
process to make white paper can result in the cellulose being more susceptible to oxidation
than it would otherwise be, contributing slightly to the discolorization of the pages in the
long run. Today, to combat this, many important documents
are now written on acid-free paper with a limited amount of lignin, to prevent it from
deteriorating as quickly. As for old historic documents, there may not
be a way to reverse the damage already done, but one can prevent further damage. It is important to store the documents, books,
or newspaper in a cool, dry, dark place, just like how museums store historic documents
in a temperature-controlled room with low-lighting. Additionally, do not store them in an attic
or basement; those places can get humid and can have significant temperature swings. If one would like to display the newspaper
or document out in the open, put it behind UV protected glass to deflect harmful rays. Most importantly, limit the handling of said
document or newspaper – nothing destroys a valuable piece of paper like frequent handling. Bonus Fact:
Ever wonder why blueprints are blue? Well, wonder no more: Making copies of architectural
drawings hasn’t always been the easiest thing in the world to do. For the majority of human history, the most
economical solution was simply to have someone make a tracing of the original plans. In the mid-nineteenth century, the process
abruptly became much quicker and easier thanks to famed polymath Sir John Herschel. In 1842, Herschel invented a method to easily
copy drawings using potassium ferrocyanide and ammonium iron citrate. The exact method, called cyanotype, is performed
as follows. First, you take a drawing of the plans done
on relatively translucent tracing paper or cloth and place it on top of and attach it
to paper (or sometimes linen, Mylar, etc.) that has been previously soaked in a mixture
of the aforementioned two chemicals, then dried. Next, you expose the papers to a bright ultra-violet
light source, such as the Sun, for several minutes. The result is that the paper soaked in the
chemicals ends up turning blue as the chemicals react to the light and form a compound called
blue ferric ferrocyanide, also known as “Prussian Blue.” This wouldn’t be very helpful for making
a copy of a document except for the fact that where the light cannot penetrate the translucent
paper, namely where the drawing marks are, the coated paper remains the original color
of the paper, usually white, effectively making a nice copy. You might see a potential problem here in
that you then can’t expose the un-blued bits to any bright light source at first,
but this problem is easily solved by simply washing the chemicals off, then allowing the
paper to dry. At this point, the copy is complete. Within a few decades of the discovery of this
method of copying (as well as other blue-printing methods such as one developed by Alphonse
Louis Poitevin in 1861 using ferro-gallate), the price dropped to about one-tenth the cost
of having someone simply trace the original plans, helping the popularity of blueprints
explode. In the mid-twentieth century, copying methods
such as as diazo prints, and then later xerographic prints, finally supplanted blueprints. Much more recently, simply sticking with digital
versions of plans has become popular, with these having the advantage of being easy to
modify and distribute as needed during the construction process. Despite the technological changes and the
fact that these plans usually aren’t on blue paper anymore, in popular vernacular
the term “blueprints” has stuck around anyways.

Comments 100

  • Lignin Deez nuts

  • Love this one too! Thought I knew but didn't. Now I do and am better for it.

  • Bonus Fact: Prussian blue, also known as potassium ferric hexacyanoferrate, is used as a medication to treat thallium poisoning or radioactive cesium poisoning, I only know this because I just wanted an episode of NCIS (it was in Season 4) that talked about it

  • Simon,
    Not sure about the proper English pronunciation of Raleigh (named for Sir Walter), but we here in North Carolina pronounce it as "Rah-lee."

  • I love how you say Raleigh lol

  • this process keeps me in business. i build and service cranes in paper mills all over the US. cool to learn

  • Episode idea: Where did the myth that says "dinosaur bones are planted and dinosaurs never existed" come from?

  • Bonus fact: Malaclypse the Younger advised to never consume acid free paper

  • Our town has a paper mill & it stinks so bad! We’ve been lucky enough to always live outside the downtown area, a few miles away you don’t smell it unless it’s really wet outside &/or windy

  • A shout out to Mimeograph would be s bonus fact

  • I thought he said ligma

  • This channel is everystoners 3 am thoughts. I love it

  • Because it looks cool

  • It is actuallly bad for you to watch tv upside down.

  • When we buying an old house I found a Sears-Roebuck catalog in a basement from 1908. I tried to pick it up and put my thumb through it! 
    Acid-based paper made from wood pulp has a limited lifetime.

  • If you can get to, say, an academic library with large holdings of old journals, go and look at the old periodicals from the 1920's or so. They look fine. Then figure out when marijuana was made illegal and look at those from after that. The paper is disintegrating because they stopped making it with hemp. This is extremely noticeable and quite a headache for librarians.

  • I think learning about Prussian Blue was the highlight of the video

  • Hey Daven, Simon et al., I'd LOVE to hear you talk about the invention and success of the Fleshlight.

  • Why are most Italian dishes made with Tomatoes if tomatoes aren't native to Italy?

  • Hey guys, can you tell us about the polls and petitions that show up on Facebook? You know, the political ones that way "we only need 199 more signatures to be able to do McConnell into a dunk tank" for example. Does 'signing' or joining or whatever really do anything besides give them your info? If some are legit, how do we tell?

  • Are the yellow pages yellow because of that?

  • Simon has the perfect voice for talking about old books 😀

  • I'm trying to go to bed, damnit

  • Damn, good question. I've always wondered that too, why the paper turns yellow after a while. Thank you for answering this question for us. I was genuinely curious as to why the paper on some documents and other things turn yellow or a kind of cream color, so again, thank you for answering this question for us.

  • Today I found out, is such a perfect channel name because I'm always learning something new from watching your videos, so thank you for that. I love watching your videos because I always leave satisfied that I learned something new today, thank you. I appreciate the information that you put out there and just genuinely love your content.

  • Now I know why my parents used newspapers to beat me. Thanks lignin!

  • Even some of my plastic mecha models turn yellow over time. So they cheated me and were selling wood!

  • This is exactly what I needed at this moment

  • Cloth paper is still used a lot for money. US bills are made from cotton cloth.

  • Similar story with the vernacular CC (Carbon Copy) which was exactly that back in the days of the old typewriter. It was a physical carbon sheaf stuck between 2 sheets of paper to create a duplicate of the type.

    Still use this in E-mails which is kind of funny…

  • We had a blueprint machine in high school, and used it in an architectural drawing class. We also, however, had very easy to use architectural software that was way more fun to play with and produced better results.

  • How about a video on the origin of the phrase "grease lightening?"

  • Very good video 😀

  • Thats really interesting

  • Can an x president join the military or any emergency services and if yes what would the secret service agents do.

  • i thought it was because they were meant to be yellow

  • Can’t believe I’m watching this for entertainment on a Friday night.

  • I had a dream last night that the latest TIFO video was narrated by Amy Adams instead of Simon. But the best part was that Simon was sitting next to her the whole time, constantly interrupting and saying how much better a job he could do. I dont remember what I was supposed to learn, but I know it had something to do with Charles Darwin, pigs, and 3d printing.

    Moral of the story: Simon, don't collab with famous actors or actresses because you do just fine on your own.

  • My question is why the old book smell is so pleasant to so many of us.

  • The dreaded drooring is back again. Laura Norder's intrusive r.

  • Oxidizing. Duh.

  • In a job I had before I went to university, I worked in a drawing office. They used a kind of plastic sheet for design drawings, which were then fed into a large machine which did indeed produce actual very stinky blueprints. This was in the 1980s

  • Bonus bonus fact: blueprints are a legal contract, and a physical copy must be on the site until completion

  • Dude, it is pronounced Raleigh like Raw-lee.

  • WRONG! Paper arrived in Europe in early B.C. , NOT the 11th century! << "[paper] Scrolls were used by the ancient Greeks. In Roman usage the scrolls were written latitudinally, usually placed on podiums with roll holders from which the rolls were unwound.The Romans eventually found the scroll too cumbersome for lengthy works and developed the codex, which is a book, with individual pages bound together." -WiKi …Jeez! 00:31

  • I'm just mad about Saffron
    Saffron's mad about me
    I'm just mad about Saffron
    She's just mad about me
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    I'm just mad about Fourteen
    Fourteen's mad about me
    I'm just mad about Fourteen
    She's just mad about me
    They call me mellow yellow
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    Born high forever to fly
    Wind velocity nil
    Wanna high forever to fly
    If you want your cup our fill
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    Electrical banana
    Is gonna be a sudden craze
    Electrical banana
    Is bound to be the very next phase
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    Saffron, yeah
    I'm just mad about her
    I'm just mad about Saffron
    She's just mad about me
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow
    (Quite rightly)
    They call me mellow yellow

    Source: LyricFind
    Songwriters: Donovan Leitch

    I forget how weird these lyrics are! A lot of people thought it was about a form of LSD, probably but these things are quite often misunderstood, certainly a lot of Beatles songs seen as drug inspired had nothing to do with drugs. However on a different note the bit about "I'm just mad about Fourteen. She's just mad about me" seems pretty disturbing somehow now.
    From memory (it was all a very long time ago) Mellow Yellow acid was a blotter so yes a yellow piece of paper (got there in the end).
    Hey Simon, maybe a TopTenz 60s/70s songs that were not really about drugs!

  • Why does water make paper weaker?

  • Too much bs. Just tell me why

  • FYI – I'm sick of covering the top-left corner of the screen with my hand during these videos to avoid a glaring blue light burning my retinas the whole time. I'm probably going to stop watching them.

  • It's called "OXIDATION", Trentpx 🙄

  • Let's see…paper was invented in 100 BC. Was the band-aid invented in 99 BC? 🙂

  • first thing i thought when i saw the title was Yellow Pages lol

  • Got an idea. I’m southern. Southern but not to be confused with country or hillbilly lol. People always say when it rains and the sun is shining at the same time that the ‘devil is beating his wife’. Why on earth do they say that and when did it originate? Thank you! Love the channel!

  • You just wait.. I'll come up with an amazing question! Lol hope it makes it to a video when I do

  • I love all the research you guys do! Thanks again!

  • This warms my drafting heart!

  • Real Blueprints also had a distinct smell of ammonia.

  • In Serbia, saying someone's birth certificate is getting or has gotten yellow is an idiom for getting old.

  • Viewer: why paper yellow?

    Simon: Well the long and storied history of paper begins with……

    This channel is fantastic.

  • Wood pulp is absolutely NOT as durable as cotton paper.

  • Logo for the new channel is looking proper!

  • Books don't yellow as quickly as newspapers? You've forgotten about 'pulp fiction' paperbacks. Mass produced and printed on cheap paper, they turned yellow before you reached the end.

  • When did people start hard boiling their eggs?

  • Bonus fraction: Simon was born and raised in New Jersey.

  • How long have you been wanting to say the line "beaten to a pulp"? Certainly made my morning…

  • I have books from 19th C and before and their pages are neither grey nor brittle. I imagine they were printed on cotton.

  • Why does milk make cascading bubbles when you blow into a straw into it?

  • I found the blue print part more interesting!

  • I just need to read the title to know the racist implication…

    Don't forget to say we're too meek to even care to speak.

  • Don't eat citrus fruit near books, either. I was peeling an orange near my first edition dungeon masters guide and the paper turned yellow almost overnight. The rest of the book isn't very yellow, even 30 years later.

  • Want to die? Take a shot every time he says “paper”

  • What about hemp paper?

  • That blue print trick is similar to the the test for ferric iron in tissue.

  • It seems to me that if you're going to display a document in a sealed container… removing the oxygen (replacing it with an inert gas such as argon) would be a good idea since part of the problem is oxidation

  • No wonder people think educational videos are boring

  • Took nearly 2000 years for the west to copy wood based Chinese paper

  • Why does paper turn yellow? You guys running out of legitimate content? Here’s a question for a later video…why is Simon Whistler so creepy?

  • I was a draughtsman for many years coated linen when boiled made very good white linen

  • 100B.C: Hemp beaten to a pulp by the Chinese.
    2019: Chinese protesters beaten to a pulp.

  • The word you were looking for is "discoloration" 😉

  • So basically… The paper is rusting…

  • I enjoy your videos but in this one you talked too fast and I wasn't able to understand some of the words. Still, I did enjoy what I was able to understand.

  • I'm confused, how is wood fiber not plant fiber? Wood comes from trees. Trees are plants.

  • His name is Simon and he likes to do drawrings.

  • Blue-prints are blue only in USA. Basically everyone else uses usual white paper and black drawings. Honestly, as if it was not enough of Imperial measurements units!

  • I wonder what you did that changed up the algorithm to cut half of your viewership.

  • I like to do drawrings

  • Vsause michael here

  • Wait a sec. You said that cellulose absorbs light and so appears white, and as it ages it starts to reflect yellow light. But shouldn't it be the other way around? We see something as white when it reflects all light, and black when it absorbs all light, so cellulose should reflect all light but over time it starts to absorb some blue wavelengths making the reflected light more yellow. Am I missing something?

  • I knew the talk about lignin was gonna be important because of the close up camera transition to Simon. 2:56.

  • Bonus Fact: The capital of the Tarheel State, AKA North Carolina, does not, as you have so said, sound like "rally" but basically rhymes with "Molly." If you wrote it as it is spoken, it would be "rah-lee."

  • We had a blueprint machine in high school.

  • I'm surprised I haven't found anyone making a joke along the lines of "Lignin balls" or something immature like that

    Am I the immature one for expecting something like that?

  • Dude go to the point

  • Just removing stuff my daughter grew out of, I realized a lot of white plastic yellows severely from sunlight, even when far inside the room, and with the window to the north. Not all plastic, though.

  • I have a Chevrolet parts manual from 1933 which was printed with low quality, cheap paper which is thicker than but similar to newsprint paper pages. The cover is also a thicker brown paper. The edges of some of the pages look absolutely charred but I don't believe this is from high heat but a slow oxidation. In fact the outer edges of the charred pages were so oxidized they fell off as ash. I have always attributed this to slow oxidation rather than fast oxidation, AKA burning.

  • Is this also a similar process as to why some old white plastics turn yellow after a couple of decades? Old retro computers are getting yellower and yellower

  • “A compound that makes wood harder and stronger.”

    That’s what she said.

  • Cellulose and ligma

  • How did we move from inking quills to ballpoint pens?

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