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 4

Unit 4:

• Encapsulation• Disaster recovery• Use and Handling

Encapsulation

• If you have single sheets that are handled frequently you may to choose to encapsulate them to provide the items with extra support and to help keep in clean.

Encapsulation • Encapsulation is when two pieces of polyester (like Mylar or Melinex) are bound in some way around an item like a capsule. The electrostatic nature of the polyester keeps the item in place. The polyester should not have plasticizers or coatings.

• You can use 2-6 mil polyester depending on size and bulk of item. On large items, use 5 mil on back for more support. 3 mil is most typically used and only for thin items. Bulky items will not keep their static.

Encapsulation More to Know

• Encapsulation is reversible. Cutting the polyester along a weld or tape line will allow the you to remove the sheet from encapsulation.

• Encapsulation will increase your bulk by 2 and weight by 3 times. Do have sufficient storage space?

Encapsulation More to Know

• Do not encapsulate friable material such as pastels or charcoal as the media may come away from the substrate and adhere to the polyester.

• Items should be deacidified before being encapsulated as the deterioration of acidic materials is accelerated by complete enclosure.

Encapsulation Methods• We will address each of these methods in

the following slides.

• Ultrasonic Welding

• Edge or Heat Welding

• Double-sided Tape

• L-sleevesPictured is an ultrasonic welder

Encapsulation Methods• Ultrasonic Welding: This process creates

a bond at the molecular level using sound waves.

• Advantages:– Does not create “pillow” effect. Flat seams– Good for doing internal and free form welds

permanent- uses no harmful materials or harmful processes

– Fast to construct

• Disadvantages:– Very expensive machine (20k +) – Skill needed to use and maintain machine

Encapsulation Methods• Edge or Heat Welding: creates bond

using heat to melt the polyester.• Advantages:

– No harmful material used– Permanent – Less expensive then ultrasonic welders

• Disadvantages:– Planar distortion- creates a bubble along the edge

making it more likely to lose its static hold – Heat and vapor can be harmful to item – Polyester must be cut and placed very accurately to

get a good weld – Not consistent

Encapsulation Methods• Double-sided Tape: an example is

3M Scotch Brand Double sided tape#415

• Advantages:– Easy, quick – Lower skill level needed

• Disadvantages:– Can lose static hold causing the item to

shift into the tape; the adhesive is harmful to the encapsulated sheet and is hard to remove

– Not permanent; tape may lose adhesion depending on storage and handling

Encapsulation Methods• L-sleeves: not encapsulation• Advantages:

– Easy to remove item – Good alternative– Provides some protection– Can buy pre-made

• Disadvantages:– Item not completely protected– Item may have tendency to slip in an L-

sleeve, depending on size and bulk.

Water Disaster Case Study

• Lets take a look at some lessons learned by the University of Hawaii, Manoa after they were hit by a flash flood.

• University of Hawaii, Manoa had a flash flood in 2004.

• Library had extensive amounts of water and mud pouring through the building. The map collection was hit especially hard.

Water Disasters: A Case Study

• Folders absorbed some of the damage, protecting items more than those that were not foldered.

• Items near the top and bottom of drawer suffered more than items in the middle Items in the middle were relatively protected, usually only suffering mud damage on their edges.

• Non-encapsulated maps often more damaged than properly encapsulated maps, BUT some of the most damaged items were encapsulated, with severe staining and cockling. This was in part due to poor encapsulation techniques.

Water Disasters: A Case Study

Lessons learned at U of H

• Double-stick tape failed and as the waterlogged paper expanded, it adhered to the edges of the adhesive.

• Ultrasonic welds had breaks in the seams, which provided an opening for water and mud to enter. Seams should also have been examined, looking for any potential breaks and tested for strength by pulling the polyester in opposite directions.

Water Disasters: A Case StudyLessons learned at U of H

Test Your Disaster Recovery Savvy:

In a water disaster, water has streamed into your map cases. Some of the materials are in folders made from blue cloth. Others are encapsulated but water has penetrated the seal.

What should you do?

Test Your DisasterRecovery Savvy:

• Remove items from cloth folders to prevent staining

• Remove from encapsulation and air dry on blotter paper

• A big challenge is going to be material resources and space!!

Flattening• Flattening may be

necessary for items that have rolled for so long they no longer lie flat.

• This can be done for items in GOOD condition.

Flattening• For items in good condition, you can

often flatten by placing under large sheet of plexiglas or acid-free sheet of paper or blotter and uniformly distributed weights. Leave out for a week or so and the natural humidity in the air will take care of most modern oversized materials in decent shape.

Flattening• What do we mean by GOOD?

Items that are NOT:– brittle – photographs– friable media– fragile

• Flattening can be tricky sometimes, so it’s a good idea to have some training in this before you attempt it, and to avoid problematic materials. When in doubt leave it alone and send it to a conservator.

Flattening• Humidification and flattening is

another way to do this—basically, you introduce moisture into paper so that it can be returned to a flat plane from a rolled or folded state—if done incorrectly, you can damage your oversized material forever, so hands-on training is recommended.

Flattening• WARNING WHEN FLATTENING ITEMS:• Coated papers, parchment, vellum, and

items with moisture-sensitive inks are all moisture reactive. Photographs have so many layers and each layer may react differently to moisture, you should not try to flatten unless you know what you are doing—otherwise you could damage the emulsion or cause the layers to separate.

• Send these items to a conservator!

New Version of the Old• We have been talking about how to

handle the physical items, but you may find that the best way to protect some popular oversized materials while still providing access is to digitize them.

Scanning Oversized Items• For oversize objects, you have few

options that protect the original—you can make a surrogate with a film or digital camera, or you could purchase a scanner that is meant for oversized objects.

• DO NOT use scanner that is smaller than size of original object. You have the potential to permanently harm the original.

Scanning Oversized Items• Digital cameras may be a more cost

effective way to digitize oversized material. They are also have less potential to harm three dimensional materials or fragile objects.

• Make sure that you purchase a digital camera that has a high resolution—your typical mass market cameras will probably not provide enough detail to meet your needs.

Scanning Oversized Items• The camera that is appropriate for most

institutions is a DSLR—that stands for digital single lens reflex. These cameras function like a traditional 35 mm camera and have double the capture area of a traditional point and shoot camera.

• These cameras can be purchased through retail and professional camera stores.

Scanning Oversized Items• Extremely large materials may require

a Scanback camera—they are great for very large materials and for items that need impeccable color details. They produce VERY large file sizes and are more expensive that DSLR’s.

• If you need that level of detail, most institutions will be better served to outsource the digitization rather than purchasing extremely expensive equipment.

Exhibits

• Consider the condition of the item - this will affect decisions about exhibition, treatment, and storage.

• Items should not be exposed to light for more than three months at a time. If you are planning on displaying your oversized material for longer than that, you should consider using a facsimile.

• Limit light exposure to 15 foot-candles or 150 lux., measurable with a light meter.

Thinking about exhibiting your item?

Exhibits

• Because some inks are not lightfast, they are even more vulnerable to light damage.

• To protect oversized materials from ultraviolet light, filter it out using filtered glass or plexiglas. You can also purchase a film for windows that blocks the light, but this can be tricky to apply and will have to periodically be replaced.

• Display items close to flat as possible and make sure that the entire document is supported

Thinking about exhibiting your item?

Exhibits• Use high quality archival matting materials

from a reputable dealer.– see NEDCC document on matting and

hinging• http://www.nedcc.org/free-resources/

preservation-leaflets/7.-conservation-procedures/7.4-how-to-do-your-own-matting-and-hinging

– see NEDCC document on framing• http://www.nedcc.org/free-resources/

preservation-leaflets/4.-storage-and-handling/4.10-matting-and-framing-for-art-and-artifacts-on-paper

Use and Handling PoliciesGood use and handling policies and

practices will:• Reduce wear and tear • Will prevent damage from improper

handling techniques.• Help avoid security issues and reduce

theft• Should be written down and posted in

work areas! This is especially important if oversized materials are accessible to the public for browsing.

Handling by Staff• Clean hands often, and do not use

lotions before handling items.• Pull folders out one at a time to

access folders in the bottom of the drawer.

• Do not allow staff to slide folders out from under other folders. – At the very least remove all folders on

top of the folder that you need and replace them in the drawer once the folder you need has been removed.

Handling by Staff• Lift items by lifting opposite corners

– if item is encapsulated and heavily used, be aware that this practice may wear out the weld

• Larger items may need two people

Handling by Staff• Use Proper Enclosures

– Maps should be transported in folders. You may want empty folder around if you have multiple items in a folder and do not want to take the entire folder to the researcher.

– Reserve space for maneuvering large folders.

– Make sure you can transport materials safely from storage to reading room. You may want to get an oversize cart- just be sure the doors are wide enough to push it through!!

Map Cart

This is a specially made map cart. It’s gentle curve allows the cart to get through a narrower space than if the objects were placed completely flat on the cart.

Special Handling for Photographs

• Use cotton gloves – photographic images are very sensitive to oils from hands.

• Store collections by type and size if possible.

• Isolate and support brittle or damaged material.

• Use enclosures that pass the Photographic Activity Test (PAT).

• Don’t try to flatten rolled photographs- send to a conservator to flatten.

Use & Handling For Patrons

• The reading room must have furniture large enough to support larger items, or materials will be at risk from bent corners and torn edges.

• Patrons should not unroll or unfold brittle paper- this is a very slow and tricky process that should not be left to users with no or little experience.

• Be aware of dangling jewelry, loose clothing, i.d. tags, etc. They can tear and scratch surfaces.

Use & Handling For Patrons

• Do not allow use of tracing or drafting tape that can damage materials.

• Encapsulate or create facsimile for high-use or damaged items to prevent further damage.

• These rules also pertain to the staff!

Section 4 Quiz

What did you learn?

Section 4 QuizQuestion 1:Which of these is not a form of

Encapsulation?• A. Ultrasonic Welding• B. Edge or Heat Welding• C. Double-sided Tape• D. L-sleeves

Section 4 QuizQuestion 1:Which of these is not a form of Encapsulation?• A. Ultrasonic Welding• B. Edge or Heat Welding• C. Double-sided Tape• D. L-sleeves

Answer : D. L-SleevesL-Sleeves are a protective enclosure, but they are open on two sides and do not encapsulate the item within.

Section 4 QuizQuestion 2:You can flatten an oversized item

by• A. placing it under a large sheet

of plexi or a sheet of acid free paper and uniformly distributed weight.

• B. humidifying the item.• C. putting it between your

mattress and boxspring.

Section 4 QuizQuestion 2:You can flatten an oversized item by• A. placing it under a large sheet of plexi or

a sheet of acid free paper and uniformly distributed weight.

• B. humidifying the item.• C. putting it between your mattress and

box spring.

Answer : A & B. Both are methods that could be used to flatten an item in good condition.

Section 4 Quiz

Question 3:The sun is the best source of lighting for an exhibition of your oversized posters.

True or False

Section 4 QuizQuestion 3:The sun is the best source of lighting for an exhibition of your oversized posters.

Answer : False – Many inks are not light fast and will fade with prolonged exposure to light. UV radiation from sunlight can also damage the substrate. Use reduced light levels and UV filters for all your exhibits.

Thank You!

Contact us if you have any questions.

LYRASIS Preservation Servicespreservation@lyrasis.org

1-800-999-8558