lyrasis mammoth materials unit1

Mammoth MaterialsHow to Preserve Posters,

Maps & Drawings

LYRASIS Preservation Services

Funded in part by a grant from the National Endowment for the

Humanities, Division of Preservation and Access

Unit 1

This class was created by LYRASIS Preservation

Services• Education and training: full-day workshops, live online

and self-paced classes• Information and referral: call us with your preservation

questions!• Loan services: we have environmental monitoring

equipment available for loan • Publications: all types of preservation publications,

downloadable for free• Disaster assistance: We are available 24/7 to assist you• Consulting: personalized assistance for your specific

preservation needs.

For more information: www.lyrasis.org/preservation

Learning Outcomes• To identify types of oversized

materials,• To understand how to properly

house and store items, and• To create use and handling

guidelines to minimize damage.

IntroductionThis class is divided into 4 main sections:Unit 1:• Longevity and stability factors of oversize

materials• Looking at substrates• Stability of inksUnit 2:• Architectural and map reproductions• Guide to identification• Silver processes

IntroductionThis class is divided into 4 main sections:Unit 3:• Storage basics• Supply terminology• Flat vs. rolled storage• General rules for oversized storageUnit 4:• Encapsulation• Disaster recovery• Use and Handling

Oversized Materials• Maps and Posters

−Handwritten or printed, can have soluble and non-soluble inks and pigments.

• Art on Paper−Includes watercolors,

pastels, charcoal, etchings, engravings

Photo courtesy of the Georgia Archives

Oversized Materials• Architectural Drawings

−There are a variety of formats and printing techniques used in architectural drawings and reproductions.

• Photographic Material−Includes aerial, large format photography,

composite photographs, old copying processes (these also fall under architectural reproductions).

• Although oversized materials present some challenges, they also provide some really unique material—for example, this photograph is of an elaborate drawing of an alligator and a wild cat on a district plat map of Georgia.


Section l• Longevity and stability factors of

oversize materials• Looking at substrates• Stability of inks

Factors Affecting the Longevity

of Collections• Chemical and Physical Composition• Storage Conditions

• Use and Handling


of Collections• Chemical and Physical Composition• Knowing the composition of items in

your collections helps to make informed decisions on their care, storage environment and handling.


of Collections

• Storage Conditions• These conditions include

environmental conditions and the physical containers that house our materials.

More on this in Section lll


of Collections• Use and Handling• Oversized material are more

susceptible to damage due to their size. Careful handling during use reduces wear and damage to collections.

More on this in Section IV

Chemical and Physical Composition of Collections

• Let’s look at this first factor affecting the longevity of a collection.

Chemical and Physical Composition of Collections

• All the items in your collections are made up of combinations of organic and inorganic materials.

• All of these materials deteriorate at different rates over time.

• This concept is called Inherent Vice.

• Inherent Vice : The tendency of material to deteriorate due to the essential instability of the components or interaction among components.

» SAA Glossary of Archival and Records Terms

• This inherent vice, when relating to various components of an item, affects the overall stability of the item.– The more layers or materials of which an object

is comprised, the greater the chance one or more of those materials may have problematic reactions with other surrounding components.

Stability of Oversized Materials

Substrate

• The substrate is the base material that images are printed on — in the case of oversized materials, the substrate is usually paper, but it can be plastic, cloth, animal skins, etc. Each will have a different chemical make up.


Stability of the media• Is the media lightfast?

Does it resist fading? Or is it sensitive to light, like silk or color photographs?


Adhesion of the media to the paper/substrate

• Is the information/writing sitting on top of the paper or is it absorbed into the paper? Is the media friable? – Friable media = powdery media

such as pastels, charcoal or pencil that is applied mechanically without a binder and may crumble or be removed if touched.


• We will define these terms and address these questions.

Let’s start by looking at substrates.

Looking at Substrates• Lets look at three types of

substrates in the upcoming slides:–Paper–Organic Non-Paper Substrates–Plastic Film or “Mylars”

Looking at Substrates• Paper is the most common substrate used

for larger materials. May be hand or machine made. While early paper can be flexible and in good condition, most paper from the mid-1800s to the 1980s is very acidic. Stability of paper varies greatly depending on its fiber content, age, and conditions in which it has been stored.

Looking at Substrates• Rag paper is literally paper made from

linen or cotton rags. Generally, this is found in collection items pre-dating the Industrial Revolution of the 1800’s, but some limited edition books and works of art may be on rag stock. It is considered to be very stable. Since rag paper was made using a mould, these do not tend to be your largest items unless you have items made from several sheets that are glued together.

Looking at Substrates• Machine-made paper is commonly

made of wood pulp. It can also contain cotton, linen, or bamboo fibers. Generally, the higher the cotton or linen content, the higher quality the paper.

Acidic Paper• The acidic paper that was mentioned

earlier was the result of a mass production process that was developed in the mid-1800’s to turn wood pulp into paper.

• For various industrial and environmental reasons, much of the paper mass produced in North America and Europe after the mid-1980’s is acid free.

Looking at Substrates• Chemically Treated Paper:

substrates are often chemically treated. Some older copying processes require coats to the surface of the paper. Sometimes it is the residual chemicals degrading the paper, rather than the paper itself self-destructing. Some papers were impregnated with oils to make them semi-transparent like tracing-papers, but sturdier.

Looking at Substrates• Modern color printed posters are almost

always on Coated Paper, such as resin or clay coated papers—these have preservation implications because coated papers stick together in a humid environment. Photographs are often resin coated as well.

Photo courtesy of Image Permanence Institute, showing layers of a coated paper photograph.

Looking at Substrates• Organic Non-Paper Substrates

– Animal Skins (Parchment, Vellum) are very susceptible to water and humidity fluctuations. Animal skins require stable humidity and slight pressure to remain flat.

– Woven Textiles (Drafting cloth, Linen, Silk) The cloth is impregnated with starches or other compounds to stiffen for printing. Both linen and silk are also used as backing supports. In general, linen is stable, but silk is very acidic and may hasten degradation of paper.

Looking at Substrates• Plastic Film or “Mylars” can have

different chemical compositions. – (Mylar is a brand name, but it is often used as a generic term

for plastic film)

• Polyester, Polyethylene, and Polypropylene – are inert, non-reactive, stable plastics.

• Polyvinyl Chloride (PVC) – a “bad plastic” that degrades quickly, causing off gassing that will harm the other components of an item.

Looking at Substrates• Plastic Film or “Mylars” are used

on– Wash-off prints– Sepia Diazo mylars – used as ‘negatives’

for printing diazo maps (Sepia diazo also used on paper support)

– Fixed line silver Halide Prints (positives)

Plastic Film or “Mylars”• Sometimes plastic film is taped over printed images for editing/cropping notations or to protect the image surface. In this case, the plastic would not be functioning as a substrate, but it could negatively affect the image it was covering if the plastic began to degrade.

Looking at Surfaces• We have been looking at the

substrate or base materials found in oversized materials collections. Now it is time to take a look at some inks and mediums that the substrates are supporting.

Maps, Posters, ArtworkStability of Ink

• Four factors that affect the stability of inks.• Chemical composition• Lightfastness• Solubility• Acid content

Maps, Posters, ArtworkStability of Inks

Chemical composition• Ink is really pigment or dye (the

color you see) in a carrier or vehicle; the carrier of vehicle is what binds the color to the paper.

• Inks also contain additives to adjust fluidity, speed of drying, surface absorption, etc.

• Some inks are stable while others can ‘eat’ through the paper over time.


Chemical composition• A form of corrosive ink is Iron

Gall ink…. • An interesting site that

covers ink corrosion can be found here: http://irongallink.org/


• Lightfastness−This simply means that the ink

is resistant to fading. Why is this important? Oversized materials are often hung on walls or placed in exhibits—if the ink is not lightfast, it will fade quickly, especially in spaces with ultraviolet light.


• Definitions:–Soluble: capable of being

loosened or dissolved.

–Solubility: the amount of a substance that will be dissolve in a given amount of another substance.

Webster’s Ninth New Collegiate Dictionary


• Solubility is usually determined by what carrier or binder is used. Oil based inks are not soluble, while some water-based inks remain soluble. Some inks, like iron-gall inks, have a dye component that is very soluble, but the iron part of the ink is not.


• Solubility– In general terms, the more soluble

an ink, the more likely it is to run when in contact with water or another liquid.

• Why do you need to know? This will affect preservation and conservation treatment decisions and may affect the object in cases of disasters involving water.


• Acid content−Acidic ink continues to erode

paper. (remember the Iron Gall ink!). Sometimes writing is transferred to adjacent objects or pages.

−These properties of inks will be noted in the next few slides.

Early Writing Inks and Their Characteristics

• Carbon Based Inks– Earliest writing ink– Permanent, lightfast, non-damaging

to paper


• Iron Gallotannate Inks (iron gall)– Range in color from light brown to

dark black– Can be highly acidic– Pre-1900 maps


• Aniline Dye - Based Inks, 1856 - 1890–First synthetic dye–Fades if exposed to light for long

periods–May be ‘fugitive’ or fade when

exposed to water or solvents

Maps, Posters, ArtworkChallenges of Inks

• One of the challenges with ink is that there isn’t a set formula for different types of ink. Before mass mechanization, people made their own inks, mixing the ingredients available. The same dilemma is true today. The ink in the pen on your desk today may not be the same formula as the ink in the same brand pen you buy in a year!

Printing Inks• Traditional Inks

−Pigments in linseed oil (much more stable than dye-based inks)

−Produces a stable, permanent image−Most common is carbon black

Printing Inks• Modern Inks

−Consist of pigments or dyes in oil, solvents, waxes or other carriers

−Often contain a drying agent−Less permanent than earlier inks−Formulations vary widely−Lightfastness varies

Other Artist Media• The most common

Paints used on paper are Watercolor & Gouache, but certainly any artist media including acrylic paints have been used. Watercolors were also used when hand coloring maps. Watercolors & Gouache – a more opaque version of watercolor - may remain water sensitive.


Other Artist Media• Drawings

– Ink drawings are generally carbon based and colorfast. Pastels & Charcoal are most common.

– Many drawings on paper can be handled like the other printed oversized materials in your collections, but there are exceptions.


Other Artist Media• Drawings

– EXCEPTIONS: Pastels, charcoals and

other friable media. They should be stored framed with glass (not Plexiglas or other acrylic) and framed with a mat to isolate the media from the glass itself. Photo courtesy of the Georgia Archives

Section 1 Quiz

What did you learn?

Section 1 QuizQuestion 1:• A substrate is

–A: a tool for drawing straight lines.–B: the base material on which

images are printed.–C: a boat passage.–D: a printing technique.

Section 1 QuizQuestion 1 A substrate isAnswer : B: the base material on

which images are printed.The substrate supports the print

media.

Section 1 QuizQuestion 2:• Inherent Vice is the tendency of

material to deteriorate due to the essential instability of the components or interaction among components.

True or False?

Section 1 QuizQuestion 2:• Inherent Vice is the tendency of

material to deteriorate due to the essential instability of the components or interaction among components. Answer : True This is the definition according to the Society of American Archivists

Section 1 QuizQuestion 3:• When an ink is described as “not

lightfast” what does that mean?– A: The ink runs slowly when exposed

to light.– B: The ink dries quickly when

exposed to light.– C: The ink fades quickly when

exposed to light.– D: The ink grows slowly when

exposed to light.

Section 1 QuizQuestion 3:• When an ink is described as “not

lightfast,” what does that mean?

Answer : C: The ink fades quickly when exposed to light. The ink does not stay fast when exposed to light.

Thank You!To continue Mammoth

Materials, View Unit 2

Contact us if you have any questions.

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