Tyvek

Tyvek house wrap

Tyvek coveralls

Tyvek USPS Express Mail envelope

Tyvek (Template:Pron-en) is a brand of flashspun high-density polyethylene fibers, a synthetic material; the name is a registered trademark of DuPont. The material is very strong; it is difficult to tear but can easily be cut with scissors or any other sharp object. Water vapor can pass through Tyvek (highly breathable), but not liquid water, so the material lends itself to a variety of applications: medical packaging, envelopes, car covers, air and water intrusion barriers (housewrap) under house siding, labels, wristbands, mycology, and graphics. Tyvek is sometimes erroneously called "Tyvex".

History

Tyvek is a nonwoven product consisting of spunbond olefin fiber. It was first discovered in 1955 by DuPont researcher Jim White who saw polyethylene fluff coming out of a pipe in a DuPont experimental lab. It was trademarked in 1965 and was first introduced for commercial purposes in April 1967.

According to DuPont's website, the fibers are 0.5–10 µm (compared to 75 µm for a human hair). The nondirectional fibers (plexifilaments) are first spun and then bonded together by heat and pressure, without binders.

Properties

• Light weight
• Flammability
• Chemical resistance
• Dimensional stability
• Opacity
• Neutral pH

Uses

Tyvek is used by the United States Postal Service for some of its Priority Mail and Express Mail packages. New Zealand used it for its driver's licenses from 1986 to 1999, and Costa Rica, the Isle of Man, and Haiti have made banknotes from it. These banknotes are no longer in circulation and have become collectors' items. The UK online rental company lovefilm uses it for its DVD Cases.

Some backpackers are now using homemade Tyvek ground cloths, finding that they are lighter, cheaper, and pack smaller than polypropylene tarpaulins.

Tyvek coveralls are one-piece garments made of Tyvek, usually white in color. They are often worn by mechanics over their clothes to avoid contact with oil and fuel. They can also be worn for painting to protect skin and clothes from splattered paint, for installation of fiberglass insulation, by workers in laboratories and cleanrooms, and any other use where a disposable, one-time use coverall is needed. Tyvek coveralls are also used for some light hazardous materials applications, but do not provide the level of protection of a full hazmat suit. Tychem is a sub-brand of Tyvek rated for a higher level of protection. DuPont makes Tyvek clothing in different styles from laboratory coats and aprons to complete head-to-toe coveralls with hoods and booties.

In 1976, fashion house Fiorucci made an entire collection out of Tyvek. More recently fashion retailer and manufacture American Apparel have included white Tyvek shorts as part of their range. While rock band Devo is known for wearing large, two-piece Tyvek suits with black elastic belts and 3-D glasses. In 1979 Devo appeared with Tyvek leisure suits and shirts made specifically for the band, with designs and images from the band.

Large sheets of Tyvek are frequently used as "house wrap", to provide a water barrier between the outer cladding of a structure and the frame, insulation, etc., allowing water vapor to pass, yet restricting air infiltration.

Tyvek can also be used to make protective sleeves for Compact Discs and DVDs.

It also makes a strong and waterproof motorcycle or automobile cover.

Comic book creator Neal Adams' company, Continuity Comics, utilized Tyvek covers for their comic books.

Tyvek is manufactured at the Spruance plant in Richmond, Virginia, and in Luxembourg.

Recycling

Though Tyvek superficially resembles paper (for example, it can be written and printed on), it is plastic, and it cannot be recycled with paper. And despite the fact that some Tyvek products are marked with the #2 resin-code for HDPE, it is not usually collected with plastic bottles as part of municipal curbside recycling programs. Instead, DuPont runs a program in the United States where disposable clothing, coveralls, lab coats, and other Tyvek disposable garments can be recycled, as well as providing a mail-in recycling program for envelopes.

External links

• DuPont™ Tyvek®
• DuPont home page
• Tyvek FAQ at DuPont
• Tyvek Envelope Recycling Program
• Tyvek Hard Structure and Soft Structure — What’s the difference?
• FAQ on how to recycle Tyvek coveralls and disposable clothing.
• The Mighty Wallet, a wallet made entirely of Tyvek.