Tyvek

== Description ==
[DuPont] Initially developed in 1955, this spunbonded, olefin product was trademarked in 1967. Tyvek® is 100% high density polyethylene without any fillers or binders. The fine, white, continuous filaments (0.5-10 microns) are bonded by heat and pressure to form a dimensionally stable, opaque sheet. Tyvek® is chemically stable, lightweight, durable, strong, lint-free, and acid-free. The paper/fabric is resistant to wetting, but it allows transmission of moisture and vapors. It is widely used as a wear resistant, tear resistant, waterproof paper for banners, maps, and envelopes. Applications also include filtration, packaging, bookcovers, interleaving, clean room clothing, protective garments, and carpet backing. Tyvek® is commonly seen as a protective barrier in new housing construction. In museums, the high-strength wrapping material is used a soft, lint-free, waterproof liner in packing crates and display cases. It is available in stiff (Type 10), soft (Type 14) and perforated (Type 16) forms (PACCIN). Tyvek® envelopes are used to store archival documents, photographic negatives or other small items. Tyvek® 6060 or 1073 has been recommended for paper-like labels; however, a sample should be tested before use to ensure that the ink does not soak through and transfer to the object below (Tetreault 2017).
== Synonyms and Related Terms ==
Tyvek@; Tyvek Hardwrap; Tyvek Softwrap; Crate liner
[[[SliderGallery rightalign|MFA- Tyvek.jpg~FTIR]]]
== Applications==
* Support for textiles
* Non-abrasive, tear-resistant envelopes and media sleeves
* Moisture proof liner for cases and crates
* Cover foam pads or line cavities in contour cut foam
* Light-blocking and form-fitting dust covers
* Soft Tyvek® used to make filled bags/snakes to stabilize objects during transport
== Risks ==
* Tyvek® is degraded by direct exposure to sunlight. 
* Tyvek may generate static electricity unless treated with antistatic agents.
* Degraded by Freon, pine oil, turpentine, dichloromethane, mineral spirits, ligroin, kerosene, toluene.
* DuPont: [Safety Data sheet]
== Physical and Chemical Properties ==
* Resistant to acids, alkalis and most organic solvents. 
* Fibers are 0.5-10 microns. 
* Neutral pH. Waterproof, acid-free, lint-free, resistant to mold, mildew, and insects. 
* Shrinks at 118 oC. Melting point = 135 oC. Maintains toughness and flexibility down to -73 oC.
* Dimensional stability depends on fiber thickness. Lighter weights may elongate up to 25% before breaking.
== Working Properties ==
* Type 10= paper-like, hard structure, area-bonded, smooth pattern, stiff
* Type 14= fabric-like, soft structure, point-bonded, embossed pattern, flexible
* Tyvek® is tear resistant but is easily cut with scissors or a knife. Water vapor can pass Tyvek, but liquid water cannot.
* Tyvek® can be bonded by ultrasonic welding or dielectric bonding. Heat sealing causes puckering as it often bonds to itself.
* Dupont recommends water-based adhesives (starch, dextrin, animal glues, PVAC) over any synthetic solvent-based adhesives.
== Forms/Sizes ==
Tyvek® sheets are available as 30", 36” and 60” wide rolls in length up to 100 yds long. Thicknesses can range from 6.6 mils (1025=hard, 1443R=soft), 7.3 mills (1020=hard) and 7.6 mils (14M=soft)
Various sizes of pre-made folders, media sleeves, envelopes and expansion envelopes.
== Resources and Citations ==
* DuPont: Tyvek Website
* Rachael Perkins Arenstein, Lisa Goldberg, and Eugenie Milroy, ‘Support and Rehousing for Collection Storage’ In ‘Preventive Conservation: Collection Storage’ Lisa Elkin and Christopher A. Norris (eds.), Society for the Preservation of Natural History Collections, New York. 2019. 
* Jean Tetreault Products Used in Preventive Conservation CCI, December 2017. Link
* Preparation, Art Handling, Collections Care Information Network (PACCIN)
* Rosalie Rosso King, Textile Identification, Conservation, and Preservation, Noyes Publications, Park Ridge, NJ, 1985
* Book and Paper Group, Paper Conservation Catalog, AIC, 1984, 1989
* Pam Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002
* Meredith Montague, contributed information, 1998
* AMOL reCollections Glossary -http://amol.org.au/recollections/7/c/htm
Category:Materials database Category:MWG Category:PACCINCategory:Sheet, FabricCategory: Interleaving