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Minothor t1_j925704 wrote

It depends on the chemistry used in the process, amongst other things, but probably not.

Regarding the chemistry - older (and some sulphur based modern) methods of bleaching left mildly acidic residues in the page and these caused the paper to brown over time, accelerated slightly if the paper had been exposed to the fatty acids in sebum from people's skin.

Newer methods supplement bleaching with a filler material such as calcium carbonate, partly to reduce the wood pulp required, partly to reduce the amount of treatment required to achieve a white product at the end of the day.

Pages produced in this way have little, if any acid residues and should remain white for a much longer period of time, I doubt if it would do so indefinitely though - oxygen in the air, microbes on the surface or other factors could result in slow degradation and discolouration over time.

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LucyEleanor t1_j96exox wrote

What about just light and the chemicals on the paper? Like how long would modern paper be white on the moon with no atmosphere or microbes?

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Indemnity4 t1_j98g59p wrote

It still depends on the paper source.

Particularly as recycling is more popular, there are many types of paperstock available to suit all customer cost/needs.

Regular officepaper contains optical brightening agents to make it look very white and clean. That will not last more than 25 years due to residual acid stating to dissolve the paper. Pressure has little effect on that.

If you ever have to publish a thesis or a museum/archival print, they will specify certain grades of paper. In some cases, they won't even allow other grades into the same box to prevent them damaging the archival pieces.

Acid-free paper itself comes in two types: permanent and archival.

There is a whole history of cheap paperback novels that are lost to time because they were printed on cheap paper. Same issue affects museum pieces and historical libraries.

1867 is the magic year in history when paper became worse - it is when the first factory to build wood pulp paper was built and within a decade, 95% of all paper was wood pulp - it was just so cheap and plentiful. When you hear of super old documents being found in a desert or some old library cupboard, more often than not it was printed on animal hides or rag-fibre. Modern wood pulp paper has fundamental chemical differences that mean it is always slowly decaying. Additives are required to slow the decay, but eventually like fuel in a a car, the additives are exhausted.

In your lifetime the only printed material you have likely seen that isn't wood pulp paper is the US currency. That is still printed on rag paper.

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Minothor t1_j96hw79 wrote

The lack of a protective atmosphere would probably leave it far more exposed to radiation if kept on the surface or in a container that isn't lead-lined or the like, which would probably degrade the paper...

But this is getting more convoluted and more than my limited knowledge and understanding can provide for - your best bet might be to reach out to Randall Monroe of XKCD.

Heck, it's the kind of question that belongs in his book: "What If?" https://www.amazon.com/What-Scientific-Hypothetical-Questions-International/dp/0544456866

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