To Preserve and Protect
Version : 2.1 (1/2)
Date : 1 February 1997
Written By : Paul Adams
e-mail : pa...@erc.msstate.edu
Confused about how to protect and store your comic books, or whether you
need to at all? I certainly was and since people in the Usenet group
rec.arts.comics.misc often post contradictory information, I went and did
a bit of research and this is what I found. Not surprisingly, there is
contradictory or incomplete information in the press as well. I have
tried to weed these out. Comments, constructive criticism, &c. are welcome.
Flames are ignored.
As always, no warranties are expressed or implied; this document may
contain errors; any action you take based off information in this
document is done at your own risk; I disclaim all liability for
direct or consequential damages resulting from use of this information.
In short, you are responsible for your own actions.
Finally a note on the price for these items. The prices quoted here
are an average price. With a little bit of looking you can find better
as well as worse deals. Generally the more you buy of an item, the less
expensive it will be. For example, acid-free boards can be bought at
about 6 cents for 1000 boards via mail order with shipping included. At
the local store acid-free-at-time-of-manufacture boards go for 10 cents
per board. In other words, shop around before buying.
Changes since version 2.0 include :
Minor correction to contributers list.
Table of Contents:
I. Protecting Your Comics ( Short Version )
II. Protecting Your Comics
III. Paper and its Deterioration
IV. Protecting Against Damage
V. Comic Bags
VII. Backing Boards
XI. Sources for Supplies
XII. Sources Consulted
I. Protecting Your Comics ( Short Version )
How do I preserve my comics?
- First, handle the books with care. More damage occurs from mishandling than
will ever occur by any other means. Secondly, store the comics a dark, cool,
dry place. Third, bag and board your comic collection.
Why bag a comic book?
- Bag your comics to protect them from damage from water, insects, and people.
What type of bag do I need?
- For long term storage use only Mylar bags. For intermediate storage,
meaning for about two years, polypropylene or polyethylene bags will do.
What type of backing board do I need?
- For long term storage use only "acid-free" boards. For intermediate
storage, "acid-free-at-time-of-manufacture" will do.
What is a good way to store the comic books?
- For long term storage buy an acid free cardboard comic book box and store
in a dark, cool place. For intermediate storage, store in a dark, cool place
using a cardboard box ( I used to use old Hammermill boxes as they are used
to carry acid-free paper ), a chest - preferably cedar, a drawer in a desk
or chest of drawers, or something similar.
Will bags harm my comic book?
- Bags made from polypropylene or polyethylene will harm your comic over time,
that is why they need to be changed every so often. Bags made from Mylar
will not harm your comics. That said, it is important to realize that
mishandling or improperly storing a comic will do more damage than a bag
What about polybags?
- Polybags, often called ploybags by those that hold them such gimmicks in
contempt, are made from polypropylene or polyethylene and thus will harm
your comic over time. They are also made thinner, at about 1.5 mil, than
regular comic bags, at about 3 mil. ( 1 mil = 1/1000 of an inch ).
Will an Archival Safe bag do?
- Archival Safe is supposed to mean that the bag or board in which you
have stored your comics will not harm the comic itself in the long term.
Many advertisers claim their bag is Archival Safe, but unless they use
Mylar D or Melinex 516, do not bet your comics on it. Many advertisers
claim their board is Archival Safe, but unless it is "acid-free" with a
3% calcium carbonate buffer, do not bet your comics on it.
II. Protecting Your Comics
Before delving into how to protect your comic books, some terms first
need to be defined so that there is no confusion by what is meant.
Preservation means those steps taken to insure that an item remains in its
current state. The steps taken are generally non-intrusive and instead deal
with changing the environment in which the item is located as well as limiting
the amount of usage the item will receive. An example of preservation is
storing comics in the dark, bagging and boarding the comics, and careful
handling of the comic when reading it.
Conservation means those steps taken to prevent any further damage from
occurring to the item. Conservation includes preservation, but is more
encompassing as well. It can include surface cleaning and deacidification
as well as changing the environment ( which is preservation ) that the item
Restoration has been sometimes used as a synonym for conservation, but it
is better said to be those steps that try to return an item to its original
or an earlier state. An example of this would be to restore a comic book that
is in good condition to one that is in very fine condition.
In general, this article will deal with the preservation of comic books
and will not deal with conservation or restoration. Those topics are beyond
the scope of this article and I refer the reader to _The Overstreet Comic
Book Grading Guide 1st edition_ for more information.
Why Even Try?
With this background, the first question that needs to be answered is
"Why even try to preserve comic books when they are going to turn yellow
eventually since they are printed on cheap paper?" In the humid climates
such as the Southeastern United States, comic book pages will turn yellow
in about 10 years. In an average climate, the pages may turn yellow in
about 15 years. However, when preserved in a dry, cool climate inside
Mylar bags, preventing the pages from turning yellow can be stretched
to 40 years or more! When talking about how long it takes for the pages
to begin browning , the difference is even more astounding. In a warm,
humid climate they begin browning in about 20 years; in an average climate
it will take about 30 years; when preserved in a dry, cool climate in Mylar
bags they will begin browning in about 90 years or more! Thus by preserving
preserving your comic you can extend their lifespan by over four-fold.
Now, before looking at how to preserve comic books, one needs to
understand a bit about how paper is made and what causes it to degrade over
time. Understanding how this degrading process occurs will help you in
knowing how to protect your entertainment and monetary investment in your
III. Paper and its Deterioration
Paper is generally made from wood pulp that is suspended in water and
matted into sheets. This can be done in one of two ways. The first way
is take logs, shred them, and form pulp. This is the cheaper of the two
ways and is thus used most often in newsprint and comic books, but it
leaves impurities in the paper. Up to one-third of the paper can be
composed of these impurities such a lignin, a complex woody acid. Lignin
breaks down in the presence of oxygen and ultraviolet light. This
light-induced oxidation of lignin is what turns newsprint yellow.
The second method has the wood fibers being prepared by digesting wood
chips in chemicals. During this process, much of the lignin and other
impurities are removed. This process is more expensive and is thus used
most often in stationary and hard cover books.
Other ways paper can deteriorate, other than light-induced oxidation
of lignin, is by oxidation of cellulose and acid hydrolysis. Oxidation
of cellulose occurs when oxygen molecules in the air attack the cellulose
fibers in the paper causing the paper to darken and increase in acidity.
Acid hydrolysis is a reaction involving heat and acids. The acids can
come from the lignin, the air itself, oxidation by-products, &c. Finally,
there is evidence that links light to the start of biological processes
that lead to brown or rust colored spots, more commonly known as foxing.
Acidity and alkalinity are measured in units of pH on a scale from 0 to 14.
A pH of 0 is the most acidic; a pH of 7 is neutral; a pH of 14 is the most
alkaline. The pH scale is based on powers of ten, thus a pH of 3.5 is 10
times more acidic than a pH of 4.5. Newsprint usually has a pH of around 4.5
when it is new while degraded paper may have a pH of 3.5. Although some
paper today is being made acid-free, the paper from which comic books are
currently being made are not.
Finally, extremes of humidity and temperature, insects, rodents, mold,
small children, careless friends, &c. can cause a comic book and the paper
it is printed on to deteriorate.
IV. Protecting Against Damage
Simply storing comic books upright or flat in a cool, dry, dark place and
properly handling them will go a long way towards preserving them. A cool
place helps prevent acid hydrolysis; a dry place protects against humidity
damage; a dark place will help prevent light-induced oxidation of lignin.
Outside of proper handling of a comic, the easiest way to preserve it is
to limit the amount of light the comic gets, both in terms of quantity and
quality. The quantity of light is how long the comic is exposed to the light.
The quality of light refers to the type of light that a comic receives. It is
simple to see how to limit the quantity of light, but what type of lighting is
of the best quality? Incandescent bulbs are the best quality light to expose
comics to when reading - and they are meant to be read and enjoyed, not locked
away in some dark hole forever. Natural light from the sun has, and
fluorescent lighting fixtures produce, ultraviolet spectrums. The ultraviolet
spectrums ( both A and B components ) provide the energy needed to cause
damage. It is also important to remember that light damage will occur every
time you read a comic and that the damage is cumulative.
Temperature and Humidity
More difficult is controlling the temperature and humidity of your
collection. What is desired is that the comics undergo no wild swings in
temperature or humidity. For every 10 degree drop in temperature, it is
estimated that paper life will double. Lower temperature will also inhibit
the growth of molds and fungi.
However, as the temperature drops, the relative humidity rises. Therefore
simply throwing your collection into a deep freeze will damage the comics
from the higher relative humidity. When paper absorbs moisture from air with
high relative humidity, the paper fibers expand. Similarly, air with low
relative humidity ( below 35% ) will cause the paper to lose its moisture and
the comic will contract. Thus cycling between low and high humidity will
put stress on the comic book's paper fibers and damage will occur.
One way to keep humidity from being a problem is to use silica gel to
reduce the moisture in the air. Small packets of silica gel can be found
in shipments of cameras, electronics, guns, pharmaceuticals, &c. Another
way to obtain silica gel is to order it. Ads can be found in coin magazines
for such products. One manufacturer (Hydrosorbent Co.) claims that once the
silica gel has been saturated by water, a built in indicator turns from
blue to pink. Bright blue silica gel indicates as close to 0% relative
humidity (RH) as can be obtained. Turning from blue to violet indicates
a RH between 20 and 40 percent; from violet to rose indicates a RH between
40 and 60 percent; from rose to pale pink indicates a RH between 80 and
100 percent. The device can then be reactivated in any oven.
A balance needs to be maintained then between temperature and humidity.
Internationally recognized standards for the safe storage of paper ( including
comics ) says that a temperature range of 68 to 72 degrees Fahrenheit and
50 percent relative humidity is ideal. While this may not be possible for
all collectors, attempts should be made in keeping the environment of the
collection stable. If using silica gel, a violet to rose rose color is
Other Means of Protecting Comics
Storing comics upright or flat and proper handling will keep the comic
itself in good shape. Storage in this manner, though, will not protect
against all the possible damage nor natural aging. For that manner, even
bagging and using backing boards will not keep the comic book from natural
Since bagging and boarding comic books will not stop them from aging,
why should you bag your collection? You should bag your collection
for the simple reason that you need to protect your investment, whether
investment means enjoyment or monetary. Often comic books are damaged
by insects or water. You can protect against this by bagging. Insects
do not seem to like to chew on plastic as much as they do on the paper
that comics are made out of. Similarly, bags protect against water
damaging your comics.
Bagging, as stated earlier, will not halt the aging process. To try and
halt the aging process, one might consider deacidifying the pages of the comic
and/or sandwiching the book in lucite, but deacidifying pages is controversial,
and sandwiching the book in lucite is expensive. How controversial is
deacidification? Consider this, past efforts at deacidifying have ended up
ruining comics by turning the pages yellow faster. If you still want to do
it, then get a professional. The saying "You get what you pay for" applies
Upon deciding to bag, the next question is what kind of bag do
you need to buy? The answer to this depends on your budget. You
do not need to buy a bag for every single book if you cannot afford
it. Instead you can put two in a bag back-to-back so that both
covers show. For those on a real budget, more can be put into a
bag if needed. If money is less of an impediment, then one bag
per comic is best. But still which kind of bag do you need?
V. Comic Bags
There are three main types of plastic used in making comic bags.
Uncoated and untreated polypropylene is excellent for archival
purposes. Unfortunately the only means of sealing it is to add
polyvinyl dichloride, PVDC, a relative of polyvinyl chloride, PVC.
This is harmful to the comic book in the long run. Additionally
it contains other solvents and additives to assure clarity and to
increase the flexibility of the plastic. These are also damaging
over the long run. Eventually even the bag itself will turn yellow
and develop a film on the outside. This film is the byproduct of the
reaction between the plasticizers, additives, and coatings ( such as UV
coatings which are now popular ) bag and the McGee oils used in ink.
On the plus side, polypropylene is inexpensive, costing around 5 cents
a bag, and will prevent much of the damage discussed above.
Uncoated and untreated polyethylene is a good moisture barrier, but
has a high gas transmission rate. It also shrinks and loses its
shape under warm conditions. Additionally it contains other solvents
and additives to assure clarity and to increase the flexibility of the
plastic. These are also damaging over the long run. Still, it is
inexpensive costing around 4 cents a bag.
4 mil Mylar ( 1 mil = 1/1000th of an inch ) is the most expensive
type of bag as well as being the best for archiving your comic book.
It does not degrade or turn yellow with time except when exposed to
UV light. Thus it is inert and is very impermeable to water. Its
disadvantages, besides its expense, is that in relation to the other
polybags, it is stiff. This may damage the comic book if one is not
careful. Another disadvantage is that some do not have a sealing flap
like the prior two do, while others such as Timelocks, sold by Bill Cole
Enterprises, do. Mylar type D is made by DuPont Company and is an
uncoated polyester film. An equivalent material is Melinex 516 by
ICI Corporation. Either is the preferred material for archiving valuable
documents in according to the U.S. Library of Congress. It is expensive
at about 55 cents a bag.
In order to remove the disadvantages of 4 mil Mylar, 1 mil thick
Mylar comic bags have been introduced. Since it is thinner, it
is not as stiff and is less likely to damage the comic book.
It also has the sealing flap found in the polypropylene and
polyethylene comic bags, but it costs more at about 22 cents
a bag, though less than 4 mil Mylar.
Even though these are the three main types of plastic used in bags, the bags
themselves come in a myriad of shapes and sizes. The different shapes that
they come in vary from your the standard bag to ones that can be placed in
a three-ring binder to others which have a Mylar sleeve so that the comic
can be read without your fingers touching the comic. There are basically five
sizes, though with a little searching other sizes can be found. The five
sizes are :
Golden Age : 7-7/8" X 10-3/8" ; Fits most pre 1950 comics
Silver Age : 7-1/2" X 10-3/8" ; Fits most 1950 - 1962 comics
Regular : 7-1/8" X 10-3/8" ; Fits most 1962 - 1972 comics
New Comic : 6-7/8" X 10-3/8" ; Fits most 1973 - current comics
Magazine : 8-5/8" X 11-1/8"
[ For those not understanding the notation the Golden Age size is seven and
seven-eighths of an inch wide and ten and three-eighths of an inch tall. ]
In a strict sense, an archival quality product is one that does not harm
your comic over the long haul. The Library of Congress and National Archives
standards state that the sleeves for archival storage be made of a
polyethylene-terepthalate (PET) polyester film. The only such film that meets
their requirements is Mylar D or Melinex 516.
Many advertisements are claiming their products are of archival quality,
contain no PVC, or are Mylar-like. The problem arises that many uninformed
people think that they are buying something as good as Mylar for a better
price. Beware of such products as generally they are not made from Mylar D
or Melinex 516 and are thus not of archival quality. They may be used for
short- to intermediate-term storage only. In general, if it says "contains
no PVC", "has UV protection", etc. it is not archival quality.
Polybags are made from either polypropylene or polyethylene and thus will
harm your comic over time. An example of polybagging a comic can be found in
X Force #1, which was bagged in a 1.5 mil polyethylene bag. The ink used on
the bag was a solvent with a low lead content.
Since it is known that the bag will harm the comic, what about the ink on
the bag? I have not yet found an answer to this, but I have written off to
get information on it. Stay tuned ...
Since the polybag will harm the comic, is it better then to take the
comic out of the bag and store it in Mylar? The simple answer is yes if you
want to preserve the comic. Will this not reduce the value of the comic?
Again the answer is a simple no. The reasoning is simple. If the comic is
left in the bag and the bag turns yellow and slowly damages the comic, who
will want to buy it? Another way of looking at this is provided by John
Danovich, an editor for Hero Illustrated.
Take a comic that the retailer is selling as "mint in the bag",
and buy it. Later, try and sell that book back to the retailer
as the comic by itself and the bag by itself. The comic will
be bought for the right price. Try and videotape the expression
on the retailer's face when you ask him to buy the bag.
The point is, the bag, box, or package is worthless *without*
what it holds. Therefore, it stands to reason that it is worthless
Now if a trading card or some such item is enclosed in the bag, be sure to
keep it as some dealers consider it part of the comic. If you are really
intent on maintaining the value of the comic and still think that the bag is
worth something, cut away enough of the top of the bag to take your comic out.
Store the comic in Mylar with an acid free backing board. Store the
promotional item with the comic. The polybag can be stored on the other side
of the backing board.
VII. Backing Boards
Backing boards are used to help support your comic books in upright storage
and thus keep them from damage by bending. Like paper, cardboard is itself
acidic and can contribute to the damage of comic books. Backing boards have
additives to protect against this. There are three basic types of backing
boards for use in protecting comic books.
"Acid Free at Time of Manufacture" Backing Boards
Such boards are generally spray coated with an alkaline substance.
This will protect the comic book for awhile, but eventually this
buffer will wear off and cause premature aging. It is best for
intermediate storage only, but it is less expensive being about
10 cents a board.
"Acid Free" Backing Boards
Such boards that have a 3% calcium carbonate buffer throughout and have
an alkaline pH of 8.5 or greater meet the U.S. government's minimum
standards. Since the entire board is alkaline and not acidic, there is
no buffer to wear off and no acid to cause premature damage. It is
more expensive costing around 25 cents a board.
"Active Charcoal Acid Free" Backing Boards
Bill Cole Enterprises, Inc. has a product called Life-X-Tenders (TM).
It has a layer of activated charcoal sandwhiched between two acid free
backing boards. The active charcoal is included to absorb any harmful
gases that an aging comic will give off, as well as any airborn
pollutants. The cost per board is $1.44 if you buy in lots of 25,
but goes down considerably to $0.72 if you buy 6,000 or more. :)
An obvious question about this product is if Life-X-Tenders (TM)
absorbes gases, will it ever give them off and how often does it
need to be replaced? Bill Cole Enterprises, Inc. claims in its
advertisement that the board will never give off the gases it
absorbes. The company also recommends replacing the boards every
five years at the most, more often for more expensive books.
Backing boards come in different sizes that mirror those for bags. The only
difference is that they are slightly smaller, about 1/16", in width so that
they will fit in the bag.
Mylar is a registered trademark of DuPont Co.
Melinex 516 is a registered trademark of ICI Corporation
Copyright 1994-1997 by Paul Adams. All rights reserved, but no harm askin'
\ ___ / Paul Adams
\ /___\ / pa...@erc.msstate.edu
\ \ / /