Nonwoven fabrics distribution

Textiles. A unique combination of desirable quaUties and low cost accounts for the demand for acetate ia textiles. In the United States, acetate and triacetate fibers are used ia tricot-knitting and woven constmctions, with each accounting for approximately half the total volume. This distribution changes slightly according to market trends. The main markets are women s apparel, eg, dresses, blouses, lingerie, robes, housecoats, ribbons, and decorative household appHcations, eg, draperies, bedspreads, and ensembles. Acetate has replaced rayon filament ia liner fabrics for men s suits and has been evaluated for nonwoven fabrics (79—81). 

Tape and film adhesives are terms used loosely and interchangeably for adhesives in sheet form. More correctly, tapes are supported on a web of paper or nonwoven fabric or on an open-weave scrim of cotton or nylon. Snpporting fibers are useful in that they provide a positive stop under bonding pressure. This can be nsed to control bond line thickness and often to help distribute stresses. Films on the other hand, are free of reinforcing fibers and consist only of the adhesive in thin, sheet form. 

The structure and properties of a nonwoven fabric are determined by, in addition to the properties of the constituent fibres and bonding materials, the stmctural architecture of fibres, bonding segment structure, and their distributions. The methods for the measurement of the key structural parameters of nonwoven fabrics discussed in this section include fabric thickness, mass per unit area, fabric density, fabric uniformity fabric porosity, pore size and pore size distribution, fibre orientation distribution, bonding segment structure, and their distributions. 

The nonwoven fabric mass per unit area and thickness usually vary in different locations in the fabric plane. The variation of either nonwoven thickness and/or fabric area weight determine the variation of local fabric packing density, local fabric porosity, and pore size distribution, and it thus influences the performance of nonwoven applications, such as the appearance, tensile properties, permeability, thermal insulation, sound insulation, filtration, liquid barrier and penetration, energy absorption, light opacity, and processability of nonwoven products. 

The nonwoven fabric uniformity is originally defined as the fabric mass per unit area (or fabric density) distribution in the fabric structure. The basic statistic terms of fabric mass uniformity in nonwoven industries are the standard deviation (measured parameters (eg, fabric weight, fabric thickness, fabric density, optical levels, rays absorption amounts, grey level intensity of images, etc.) as follows ... 

The pore structure in a nonwoven fabric includes the total pore volume (or porosity), the pore size, pore size distribution, and the pore connectivity. 

The analysis of the resultant data is based on the model that the pores in the nonwoven fabric are a series of parallel nonintersecting cylindrical capillaries of random diameters (or capillary tube model)." The variables of pore stractures in nonwoven fabrics obtained in porosimetry include the total pore volume (or porosity), the pore size, pore size distribution, and the pore connectivity. 

The standard method for FOD measurement using image analysis method is defined in the latest version of NWSP standards, ie. Fiber Orientation Distribution of Nonwoven Fabrics (NWSP 407.0.R0 (15)). 

A test method was designed in NWSP 150.1.R0 (15) (equivalent to ASTM D5908-96) to analyse polyester nonwoven fabrics for resin binder distribution and binder penetration. 

A specimen of the nonwoven fabric (in full width and 0.6 m in length) was dyed in a dye (C.I. Basic Red 14) solution of 60 L with a concentration of 0.2% at 120—140°F for 15 min. After resin and dry, the stained specimen is examined and rated for binder distribution on the nonwoven fabric surface and binder penetration through the fabric thickness by comparison to photographic rating standards, using the binder... 

Absorbent hygiene prodncts a great deal of nonwoven fabrics are used in hygiene products (ie, wipes, baby diapers, feminine hygiene products, and adult incontinence products) as functional elements (eg, topsheet, acquisition and distribution layer, liquid retention layer, backsheet) to promote daily hygiene standards and human health. 

A. Konopka, B. Pourdeyhimi, H.S. Kim, In-plane liquid distribution of nonwoven fabrics Part I, experimental observations, Int Nonwovens J 11 (4) (2002). http //www.jefl]oumal. org/INJ/winter02.pdf. 

This study was performed to compare thermal properties between scrub suits and clean air suits made of woven and nonwoven fabric. Thermal manikins provide a good estimate of the total dry heat loss from the body and the distribution of heat flow over the body surface these measures were used to describe the thermal characteristics of clothing. Clothing thermal insulation differences are statistically significant (p < 0.5) which means the user will perceive thermal differences between scrub suits. Regarding to fabric thermal properties there is no suit with all ideal properties. 

The thermo-insulating properties of lofty non-woven fabrics, which have been reported in several papers, depend on the nature of pore size and distribution in a fabric, which are a function of fibre fineness and material density. Jirsak et al. compared in a more comprehensive way the thermo-insulating properties of both perpendicular-laid and conventional cross-laid nonwoven fabrics. The total thermal resistance P of a textile fabric as a function of the actual thickness of the material ... 

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