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This article is written by David Beech, FRPSL and published
here with his kind consent. |
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| How to look after your Collection - A Basic Guide |
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Based on a Paper given at the 87th Philatelic Congress of Great
Britain, Derby on 8th July, 2005
.....continued
Paper
Papers are complicated in form and structure. For this basic guide it is
perhaps sufficient to say that the best papers have a pH of between 6.0
and 8.5. pH is the measure of the extent to which material is acidic or
alkaline. Paper which is acidic usually goes brown like modern
newspapers and paperback books. Philatelic material may suffer from
being acidic and the most obvious examples of this are postal stationery
post cards. Many of these are so bad that they probably have a life of
only a few years, perhaps in some cases ten to twenty years. The problem
can be addressed by de acidifying the item but it is recommended that
this be undertaken by a professional conservator. Post cards that have
been used with typewriting or manuscript addresses or messages and
perhaps with additional adhesives will need special care as the process
is one where wetting is involved. The deacidification process will
arrest the acid attack at the time of treatment but it will not reverse
the browning of the paper.
Clearly album pages should be such that they cause no damage to the
material mounted on them and so need to be acid free and comply to ISO
9706 standard for permanent paper.
Gum
As I have indicated gum is often in tension with the paper it is applied
to and this can be reduced under the appropriate storage conditions that
I give in the Environment section above. If the gum becomes too dry (and
especially if it is thickly applied) it may crack and go on to crack or
damage the paper of a stamp or cover, etc. The removal of gum is
probably in the best interests of stamps in the long term. This is
controversial and further work needs to be carried out as to how this
may be achieved with the best results. Removal by water may not be the
answer in many cases and inks may be affected.
Pressure sensitive adhesives, that is self adhesives on stamps, are
emerging as a major conservation concern. Clear tapes, like Sellotape
and other similar products, are pressure sensitive and as most of us
know the adhesive turns brown and leaves a stain on just about anything
that it has been stuck to. Will this be the case with self adhesive
stamps? By the way never repair any philatelic item with a pressure
sensitive tape; it was never designed for this purpose.
Plastics
A great deal has been written about plastics in philately which are used
as mounts and protectors. Here I am only going to say that top museums,
libraries and archives only use polyester (Mylar and Melinex are
commercial names) without any anti static coatings, with paper or
similar materials. They never use PVC which can ooze plasticisers and
forms acid as it decomposes.
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