Tyvek

Tyvek ® is a registered trademark of DuPont for a nonwoven fabric of high density polyethylene ( HDPE ), which builds up from fibrillated, closely connected to networks Feinstfilamenten in the diameter range of 0.5 to 10 microns. Two different solidification process of the deposited Feinstfaserschichten with calenders with smooth rollers or with engraving rolls once created area-based products with paper- or foil-like, slightly stiffer character ( type 10) for example, the packaging and office supplies industry or point- linked products with fabric, softer character (type 14 ), eg for protective clothing in a clean room or as a base material for chemical-resistant coatings for the manufacture of chemical protective suits. In addition, a Type 16, which is perforated with holes of 0.13 and 0.51 mm diameter, resulting in an even better textile character at elevated air and moisture permeability exists. The different types are manufactured in different surface materials.

Production

The manufacture of Tyvek nonwoven fabrics is performed after the flash - spinning technology (evaporation spunbond process ), an exclusive method of the company DuPont. Intensive development work began in 1955 and this led in 1959 to a first pilot plant and finally in 1967 to commercial production recording. Tyvek is produced at locations in Richmond, Virginia / USA and Contern / Luxembourg. A packaging company DuPont is located in Shenzhen, China.

In this method, HDPE is mixed with a solvent (e.g., methylene chloride), and heated under high pressure in an autoclave at high temperature (25 ° C or more above the boiling point of the solvent). The solution mixture is then performed with extreme precision control through nozzles and relaxed in an explosive reaction. The solvent evaporates, and it is a three-dimensional network of thin fibrillated filaments present in a strand form through an oscillating storage device to a deposit belt, which simultaneously serves as a conveyor belt placed. The result is an isotropic fiber arrangement, which has a positive effect on the tear strength. Also increased strength values ​​contributes a minimum length of the fibrillated filaments of about 120 mm, as shown in one of the basic patents of this particular non-woven fabric manufacturing process. As already mentioned, the fiber layers are solidified with calenders of different types of heat and pressure. Other treatments such as an anti-static equipment or a pressure pre-treatment by corona irradiation can join.

Properties

Tyvek acts of its deformability ago about like paper, but is more durable. As a material for protective clothing, it is safe, because Tyvek one hand even loses very few fibers, on the other hand can come out through the web almost no separated from the body cells from the suit. Thus, sterile working conditions, as they are needed in the above areas of work, be maintained.

Recycling

Although specifically the Tyvek series equals 10 external of paper, it is a plastic, it can not be recycled in the same way as paper. The company are numerous reuses available on their website. It must be noted that Tyvek, which is used for protective clothing, depending on the type of contamination may be subject to recycling special rules.

Production States

Production takes place in:

  • USA the Richmond, Virginia / USA
  • Luxembourg at the site Contern

A packaging company DuPont is located in Shenzhen, China.

Use

  • Protective clothing for clean areas or protection against pollution ( painting)
  • In the area of ​​sports sponsorship Tyvek was used in the advertising media " rotational band ", including in the matches of the German national football team
  • Packaging materials for sterile ( aseptic package for plasma sterilization)
  • Due to the vapor diffusion openness, while water resistance it is also used as a second roof skin.
  • Because of its tensile strength Tyvek is also often used as a material for control and inlet Bracelets ( party band) at festivals.
  • CD-/DVD or packaging material for shipping the media in the post. Used eg for DVD-rental service.
  • For the construction of kites Tyvek is because it is good paint, glue and sew leaves and is weatherproof.
  • Attempts around 1980 to use Tyvek for the production of plastic bank notes, however, have not been widely used except on small islands.
  • As Tyvek HomeWrap it is used for weather protection especially in houses made ​​of wood, as they are built particularly on the American continent. To this end, the house will be up to the doors and windows almost wrapped ( wrapped ). As a result, liquid water can not penetrate, but inside emergent water vapor ( gas) diffuse outward.
  • As a packaging material for art, for example, for transportations at exhibitions or for storage.
  • As a material for rain -resistant maps, useful for (motor ) cycling, ski tours, water sports.
  • Ladies handbags, purses and laptop bags
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