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Terms and Definitions for Scrapbookers
These terms and definitions are my own. I am not a chemist and I am
not a professional conservator. These terms and definitions are a result of the research
and reading I have done. To the best of my knowledge these terms and definitions are
accurate.
Scrapbooking is a strange hobby. It is being sold by independent
consultants as if it were cosmetics or kitchenware and it is being sold in craft stores as
if it were quilting supplies. The fact is scrapbooking is a craft or hobby that is
intertwined inextricably with science. Unless we are taking precautions to ensure that we
are using safe materials, we might as well place our beautiful scrapbook pages in a
magnetic album. Few of us would do that, but many of us do not know very much about photo
preservation, what is safe, what is unsafe and WHY certain materials should be used or
avoided. I hope that these terms and definitions will help you gain a better basic
knowledge. If after reading this page, you still want or need more information, a
suggested reading list follows.
- Acid - In chemistry, a substance capable of forming
hydrogen ions when dissolved in water. Acids can weaken cellulose in paper, board, and
cloth, leading to embrittlement. Acids may be introduced in the manufacture of materials
and left in intentionally (as in the addition of certain sizing, like starch or glue) or
incidentally. Acids may also be introduced by migration from other materials or from
atmospheric pollution. Discoloration and embrittlement are attributed to acid.
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- Acid-free - In chemistry, materials that have a pH
of 7.0 or higher are acid-free. This term is sometimes used incorrectly as a synonym for
alkaline or buffered.
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- Acid migration - the transfer of acid from an acidic
material to a less acidic material or pH neutral material. Remember, acid always migrates
to neutral; NEVER does neutral migrate to acid. Acid migration may occur directly, when
two materials are in intimate contact. For instance, acid may migrate from boards, end
papers and protective tissues, as well as the paper covers of albums, and from memorabilia
to less acidic paper.
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- Archival quality - In "An Ounce of
Prevention," author Craig Tuttle defines archival-quality as follows:
"Archival-quality/conservation-quality are terms used to indicate that a material is
chemically stable, and therefore, has a stronger resistance to adverse environmental
conditions". Archival quality is a non-technical term that suggests that a material
or product is permanent, durable or chemically stable, and that it can therefore safely be
used for preservation purposes. The phrase is not quantifiable; no standards exist that
describe how long an 'archival' or 'archival quality' material will last.
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- Buffered Paper- A paper that is pH neutral to begin
with and then has a reserve of Alkaline to neutralize additional acids as they migrate to
the paper. Just because you are using buffered pages or buffered papers do not assume that
you can add an unlimited number of acidic materials to your album and the acid will be
absorbed. A 1% or 3% buffer is just a small buffer and not meant to absorb large amounts
of acid. In fact many papers are buffered only because the materials used in their own
manufacture are known to become acidic over time, therefor the buffer is added solely to
protect that paper from becoming acidic in the future and is not capable of absorbing any
"extra" acids.
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- Buffering - Craig Tuttle: "The addition of
calcium carbonate, a colorless or white alkaline chemical, to paper and storage boxes to
inhibit the formation and migration of acids". My note: Please be
aware that there are differing opinions among the experts on buffering and its
desirability. Henry Wilhelm is well known to be of the opinion that buffering should not
be used around color photos. (Since Wilhelm is now affiliated with CM and CM's pages are
buffered, it should be interesting to see what changes, if any will be made in the
future.)
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- Chemical stability -Again, from Craig Tuttle:
"The ability of certain chemical bonds to resist changes in their composition when
exposed to other chemicals. Paper and photographs which are chemically stable are more
resistant to deterioration". Materials which are chemically stable are not easily
decomposed or otherwise modified chemically. This is a desirable characteristic for
materials used in preservation since it suggests an ability to resist chemical degradation
such as the embrittlement of paper over time and/or upon exposure to various conditions
during use or storage.
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- Lignin - A component of the cell walls of plants
that occurs naturally, along with cellulose. Lignin is largely responsible for the
strength and rigidity of plants, but its presence in paper and board is believed to
contribute to chemical degradation. It can be, to a large extent, removed during
manufacture. No standards exist for the term 'lignin-free' and additional research is
needed to determine the precise role lignin plays in the durability and permanence of
paper. Please note: currently most photo preservationists believe lignin
to be more harmful to photos than acid.
Mylar- Mylar (polyester) is used as a protective
clear covering for photos and album pages. Mylar is currently regarded as the highest
quality material used for this purpose.
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- Permanent paper - Craig Tuttle: "Paper
compliant with the Permanent Paper Standard ANSI Z39.48-1984 (Permanence of Paper for
Printed Library Materials), a standard created by a committee composed of the federal
government and the paper industry. To be considered permanent, and to comply with Standard
ANSI Z39.48-1984, paper must meet the following requirements:
- Must have a pH level of 7.5 or greater.
- Must contain an alkaline buffer of calcium carbonate or another
alkaline.
- Must be free of chemical impurities and, optimally, contain cotton or
other rag fibers.
- Must be resistant to tears and folding.
- Such materials may be produced from virtually any cellulose fiber
source (cotton and wood, among others), if measures are taken during manufacture to
eliminate active acid from the pulp. However free of acid a paper or board may be
immediately after manufacture, over time, the presence of residual chlorine from
bleaching, aluminum sulfate from sizing, or pollutants in the atmosphere may lead to the
formation of acid unless the paper or board has been buffered with an alkaline
substance".
pH Neutral- Many manufacturers are using this term
instead of acid free. pH neutral is more definitive than acid free. An acid free product
could be extremely alkaline. Since is is also undesirable to be highly alkaline because of
damages, pH neutral is a desirable quality.
Photo Safe- A term used very loosely by many
companies to indicate that they feel their products to be safe. I feel that there are
several problems with this term. There is no regulation of the term by a legally
enforceable standard. Because of ignorance, lack of photo preservation knowledge or a
desire to deceive, this term is used in many instances when a product is not in fact safe
to be used near photos. When a product is simply labeled photo safe, I will never take it
home and use it without first calling the manufacturer and making further inquiries.
Polypropylene-
- Preservation - Activities associated with
maintaining library, archival, or museum materials for use, either in their original
physical form or in some other format.
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Now that you've finished all of that dry reading, you ask
"Isn't acid free enough?" The answer is no, acid free isn't enough and I'll
explain why.
1) Think about all of the chemicals that you have in your home. You
know, the ones that are under your kitchen sink with a baby safe lock on them. Most of
them contain toxic chemicals. Would you want any of them near your photos? Acid is NOT the
only material that damages photos.
Papers should be acid free, lignin free, bleach free, chemically
stable. Permanent inks should be used for writing and stamping.
I hate to end here, but more will have to be added later.....
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