DuPont™ TYVEK®

Manufactured by a fl ash-spinning process, Tyvek® fabric is made of strong, continuous, high density polyethylene fi bres. The fi bres are thermally bonded into a tight, homogeneous and soft fabric that is intrinsically breathable, does not shed fi bres ( linting ) and has inherent barrier properties i.e. not reliant on a thin applied coating or layer. This unique combination of barrier protection and inherent breathability makes Tyvek® an ideal fabric for a wide range of protective applications.

MICROPOROUS FILM (MPF)

MPF fabrics are a bi-laminate material comprising a thin microporous fi lm bonded to a spunbound polypropylene base. These fabrics offer limited durability since all barrier protection is lost when the protective fi lm layer is abraded. In addition, their low air-permeability characteristics make then much less breathable than other fabrics with all this implies in terms of poor wearer-comfort and heat control.

SPUNBOUND/MELTBLOWN/SPUNBOUND (SMS)

The performance of SMS fabrics relies on a meltblown polypropylene layer sandwiched between two open polypropylene layers. This inner polypropylene layer functions as the main fi lter for particles. However SMS fabrics tend to suffer from limited durability and relatively weak barrier performance due to their relatively open fi bre structure. In addition, their high air permeability characteristics signifi cantly compromise the barrier properties of the fabric making it only really appropriate for very basic protection and as a dirt barrier.

ANNEXE 3: FABRICS - TYPES AND PROPERTIES

Annexe 3

1:500 Source: DuPont.

1:500 Source: DuPont.

1:500 Source: DuPont.

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