Science Information

Paper - More than Meets the Eye


We are surrounded by so much paper and card that it is easy to forget just how complex it is. There are many varieties and grades of paper materials, and whilst it is fairly easy to spot the varieties, it is far more difficult to spot the grades.

It needs to be understood that most paper and card is manufactured for a specific purpose, so that whilst the corn-flake packet may look smart it is clearly not something destined for the archives. It is made to look good, but only needs a limited life span. It is also much cheaper to manufacture than high grade card.

Paper can be made from an almost endless variety of cellulose based material which will include many woods, cottons and grasses or which papyrus is an example and from where we get the word 'paper'. Many of these are very specialized, but the preponderance of paper making has been from soft wood and cotton or rags, with the bulk being wood based.

Paper from Wood.

In order to make wood into paper it needs to be broken down into fine strands. Firstly by powerful machinery and then boiled with strong alkalies such as caustic soda, until a fine pulp of cellulose fibres is produced. It is from this pulp that the final product is made, relying on the bonding together of the cellulose into layers. That, in a very small nutshell, is the essence of paper making from wood. However, the reality is rather more complicated. In order to give us our white paper and card the makers will add bleach and other materials such as china clay and additional chemicals.

An further problem with wood is that it contains a material that is not cellulose. Something called Lignin. This is essential for the tree since it holds the cellulose fibres together, but if it is incorporated into the manufactured paper it presents archivists with a problem. Lignin eventually breaks down and releases acid products into the paper. This will weaken the bond between the cellulose fibres and the paper will become brittle and look rather brown and careworn. We have all seen this in old newspapers and cheap paperback books. It has been estimated that most paper back books will have a life of not greater than fifty years. Not what we need for our archives.

Since the lignin can be removed from the paper pulp during manufacture the obvious question is 'why is it left in the paper?' The answer lies in the fact that lignin makes up a considerable part of the tree. By leaving the lignin in the pulp a papermaker can increase his paper yield from a tree to some 95%. Removing it means a yield of only 35%. It is clearly uneconomic to remove the lignin for many paper and card applications.

It also means, of course, that lignin free paper is going to be more expensive, but that is nevertheless what the archivist must look for in his supplies. There is no point whatsoever in carefully placing our valuable artifacts in paper or card that is going to hasten their demise. Acid is particularly harmful to photographic materials, causing them to fade and is some cases simply vanish!

So, how do we tell a piece of suitable paper or card from one that is unsuitable? You cannot do it by simply looking, and rather disappointingly, you cannot always rely on the label. 'Acid free' might be true inasmuch as a test on the paper may indicate that it is a neutral material at this time. But lignin can take years before it starts the inevitable process of breaking down, and in the right conditions it will speed up enormously.

Added to this, as I have indicated earlier, paper may also contain other materials added during manufacture such as bleach, china clay, chemical whiteners and size. This looks like a bleak picture, and it would be but for the fact that there are suppliers who will guarantee the material that they sell. If you want to be absolutely sure that you are storing in, or printing on, the correct material then this is probably the only way.

Incidentally, acids can migrate from material to material. Lining old shoe boxes with good quality acid free paper will do little to guard the contents. The acid will get there in the end.

Paper from Rag.

Paper is also commonly made from cotton and rag waste. This has the advantage of being lignin free, but because there is much less cotton and rag than trees, it also tends to be much more expensive than wood pulp paper. You will still need to purchase from a reliable source though, since even rag paper and card can contain undesirable additives.

A reliable source for quality rag papers is a recognised art stockist. Many water colour artists insist on using only fine quality rag paper and board.

The main lesson to learn from this information is that you cannot rely on purchasing archival materials from the high street. The only safe solution is to purchase from specialist suppliers. It may cost rather more, but in the end you will know that your important and valuable data and images have the best home possible.

Copyright Peter C. Amsden 2005

Peter C. Amsden (amsden@btinternet.com) has many years experience in photography, film and television. An Associate of both The Royal Photographic Society and of the British Institute of Professional Photographers. He had made a special study of conserving and archiving imaging media and is author of "Images for the Future". Runs consultancy and web design business, for more info. see http://www.ASAT.biz


MORE RESOURCES:
This RSS feed URL is deprecated, please update. New URLs can be found in the footers at https://news.google.com/news


CNN

Trump's administration's seven banned words are an attack on science
CNN
Despite these denials, it's not hard to believe the Washington Post story. After all, this would not be the Trump administration's first attack on scientists or their abilities to communicate to the public. Since his days on the campaign trail, Donald ...
Trump's Censorship of Science Will Kill PeopleNewsweek
Reported CDC ban on terms such as 'fetus,' 'science-based' alarms health leadersSyracuse.com
Trump administration gives CDC list of banned words, including 'science-based,' 'fetus,' 'transgender'Q13 FOX
Engadget -Vox -Washington Post
all 350 news articles »


LA Daily News

Torrance Unified takes science standards seriously
LA Daily News
As schools nationwide take on the most comprehensive overhaul of science standards in 20 years, Torrance Unified has become a pace-setter. Without relying on outside funding, or major grant money, the South Bay's largest school system has trained more ...



The Verge

Read an excerpt from Eliot Peper's new science fiction thriller, Bandwidth
The Verge
A couple of years ago, I read Cumulus, a self-published book by Eliot Peper. The novel follows three characters in a near-future San Francisco, which is divided into a super-wealthy tech elite and the downtrodden customers who use their services. It's ...



Savannah Grove Elementary to become computer science immersion school
SCNow
FLORENCE, S.C. – Savannah Grove Elementary School will become a computer science immersion school, and the program is set to launch in January. Students will have the opportunity to learn fundamentals of computer coding as part of their daily ...



7 Science-Backed Ways That Show Coffee Can Actually Be Good For You
ScienceAlert
7 Science-Backed Ways That Show Coffee Can Actually Be Good For You. Coffee addicts, rejoice! KEVIN LORIA, BUSINESS INSIDER. 17 DEC 2017. Caffeine is the most commonly used psychoactive drug in the world - for good reason. It wakes us up, helps us stay ...

and more »


Study finds humanities and social science Ph.Ds working outside academe are happier than their tenure-track peers ...
Inside Higher Ed
With the dearth of available tenure-track faculty positions, professional organizations and others are working to change how Ph.D. programs prepare students for the careers they're likely to have outside academe. In good news for those efforts, a new ...



NBCNews.com

Is Star Wars' 'The Last Jedi' science fiction? It's time to settle this age-old argument.
NBCNews.com
"The Last Jedi" is built around magic and mysticism and backwards-looking nostalgia for a time of knights and royal houses. Those are tropes of fantasy, not of future-obsessed science fiction. Or is it? To figure out whether Star Wars is science ...

and more »


The Guardian

Heinz Wolff obituary
The Guardian
Heinz Wolff, who has died aged 89, was one of a long line of distinguished British scientists who became even more distinguished television presenters and apostles of science. With his trademark bow tie, quizzical look, characteristic pronunciation ...

and more »


The Verge

A century after Arthur C. Clarke's birth, science fiction is still following ...
The Verge
At some point, most science fiction readers come across the “Big Three” authors from its so-called Golden Age: Robert A. Heinlein, Isaac Asimov, and Arthur C. Clarke. Over the course of his lifetime, Clarke witnessed the birth of the space age, and ...

and more »


The Guardian

Playing God: should we revive extinct species?
The Guardian
Critics claim that although you can breed for similar appearance, you cannot recreate the animal's behaviour and ecology. The same may be true of a project to revive the woolly mammoth, which has yet to progress beyond the early stages. So what next? I ...


Google News

home | site map | Xray Photography
© 2006