Types of nonwovens

A website named TexGuide describes various ways of producing nonwovens. The methods are  

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The various types of nonwoven processes will be described in this chapter, with a special attention given to the polymer extrusion processes due to their importance for polyolefin-based nonwovens. Nonwoven processes are versatile and can be grouped under the following separate types (or a combination of them) ... 

The nonwoven brics used for encapsulation of webs in diCferent samples were of two types, i.e. parallel laid viseose (type A - 20 g/m ) and random laid viscose (type B -60 g/m ) (made out of waste fito) to get the absorbent cores. Nine different combinations of viscose/SAF blended carded webs (type 1-9) were prepared and those webs were sandwiched between two types of nonwoven fabric layers, i.e. total 18 absorbent cote samples were developed for study. The details of the samples are givoi in Table 1. This absorbent core was then swapped widi that of an available sample (market sample) and the product was tested using the developed core. The nomenclature of the sample (e.g. Al) implies a sandwiched absorbent core sample of falnic type A and web type 1. 

Nonwoven fabrics account for more PP usage than any other single fiber application. There are three types of nonwoven fabrics thermobonded, from staple fibers spunbonded and melt-blown. The spunbonded and melt-blown processes are discussed below. The fabrics from each process differ from each other in properties and appearance, and often combinations of two types are used together. Spunbonded fabrics are strong, whereas melt-blown fabrics are soft and have high bulk. 

Comparison of the procedures for the thickness measurement in three types of nonwoven fabrics defined in the test standards (BS EN ISO 9703-2 1995) can be found in other book. In comparison with the measurement of thickness of woven fabrics, the measurement of nonwoven fabric thickness requires a different sampling procedure, specific pressures at which to test normal and bulky nonwovens, a specific area for the size of the presser foot, and a shorter time to note the gauge reading. 

Several types of nonwovens can meet these requirements. Spunlaced materials, SMS (consisting of three thermally bonded layers, generally based on polypropylene) or SMMS (spunbond-meltblown-meltblown-spunbond) can be used. (Midha, Dakuri, Midha, 2012). 

Clothing products, which include articles worn by both nursing staff and patients, have no specific requirements other than comfort and durability. In isolation wards and intensive care units, disposable protective clothing is worn to minimize cross infection. A wide range of designs in various types of nonwoven fabric is available as head coverings for male and female staff. These articles are made from composite fabrics that consist of tissue reinforced with a polyester or PP spunlaid web. SMS and wet-laid are the major nonwoven types used in sterilization wrap, laboratory coats, jackets and coveralls. 

This was just one of the conclusions drawn from a study of the role different types of nonwovens play in day-to-day living carried out by the Bmssels-based organisation. 

Nonwoven filter media are usually produced by using one of six major types of nonwoven web formation methods air-laid, wet-laid, spunbonding, melt blowing,... 

A significant reason for the majority of oil and fuel system failurcs is the presence of high water levels as dissolved, dispersed, and free water, which degrades the fuels and oils. There are mainly four types of nonwoven filter media fiequently used for the removal of water contaminations contained in a wide range of fuel and oil products, such as aviation fuel, automotive diesel, and hydraulic oils. They include ceUulosic pulp filter, man-made fibre filter, glass fibre media, water adsorption (eg. 

Comparison among the different types of nonwoven fabrics on the basis of their iimitations... 

Types of nonwovens used for disposable hygiene products... 

In addition, a bieomponent filamentary bundle ean be easily eonverted into an intereoimeeted parallel web by proper thermal treatment. There are also eomposite sheets eomposed of intereonneeted parallel webs and burst fiber sheets used for a new type of nonwoven. 

The specihc stmcture of each type of nonwoven geotextile, which is a result of the manufacturing process, has a direct impact on the capacity of the geotextile to perform its function in the soil. Table 3.5 shows in greater detail the main relationships of the manufacturing process, the structure of the geotextile and its performance in the functions for which it is adapted. 

To produce a nonwoven out of a fiber web produced in the web-forming process, the fiber web has to be compacted. This can be done mechanically (needles, water jet), chemically, or thermally (Fig. 6.22). A typical example for this type of nonwoven is a woolen felt. 

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