Different Types Of Fabrics Research Articles

Development of Flax Fibre based Textile Reinforcements for Composite Applications

Most developments in the area of natural fibre reinforced composites have focused on random discontinuous fibre composite systems. The development of continuous fibre reinforced composites is, however, essential for manufacturing materials, which can be used in load-bearing/structural applications. The current work aims to develop high-performance natural fibre composite systems for structural applications using continuous textile reinforcements like UD-tapes or woven fabrics. One of the main problems in this case is the optimisation of the yarn to be used to manufacture the textile reinforcement. Low twisted yarns display a very low strength when tested dry in air and therefore they cannot be used in processes such as pultrusion or textile manufacturing routes. On the other hand, by increasing the level of twist, a degradation of the mechanical properties is observed in impregnated yarns (e.g., unidirectional composites) similar to off-axis composites. Therefore, an optimum twist should be used to balance processability and mechanical properties. Subsequently, different types of fabrics (i.e., biaxial plain weaves, unidirectional fabrics and non-crimp fabrics) were produced and evaluated as reinforcement in composites manufactured by well established manufacturing techniques such as hand lay-up, vacuum infusion, pultrusion and resin transfer moulding (RTM). Clearly, as expected, the developed materials cannot directly compete in terms of strength with glass fibre composites. However, they are clearly able to compete with these materials in terms of stiffness, especially if the low density of flax is taken into account. Their properties are however very favourable when compared with non-woven glass composites.

Effect of the fiber diameter and porosity of non-woven PET fabrics on the osteogenic differentiation of mesenchymal stem cells

The proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) was investigated in three-dimensional non-woven fabrics prepared from polyethylene terephthalate (PET) fiber with different diameters. When seeded into the fabrics of cell scaffold, more MSC attached in the fabric of thicker PET fibers than that of thinner ones, irrespective of the fabric porosity. The morphology of cells attached became more spreaded with an increase in the fiber diameter of fabrics. The rate of MSC proliferation depended on the PET fiber diameter and porosity of fabrics: the bigger the fiber diameter of fabrics with higher porosity, the higher their proliferation rate. When the alkaline phosphatase (ALP) activity and osteocalcin content of MSC cultured in different types of fabrics was measured to evaluate the ostegenic differentiation, they became maximum for the non-woven fabrics with a fiber diameter of 9.0 μm, although the values of low-porous fabrics were significantly high compared with those of high porous fabrics. We concluded that the attachment, proliferation and bone differentiation of MSC was influenced by the fiber diameter and porosity of non-woven fabrics as the scaffold.

The persistence of human scalp hair on clothing fabrics

This study reports the persistence behaviour of human scalp hairs under a number of different circumstances. The effects of artificial dyeing of hairs, the presence or absence of roots and different types of fabrics on the persistence of hair on a variety of garments were investigated. The garments were made from cotton, polycotton, cotton/acrylic, polyester and wool. The results indicated that neither artificial dyes nor the presence or absence of roots had statistically significant effects on the persistence of hair. In contrast, the type of fabric had a major impact and it was found that, generally, hairs persist longer on rougher fabrics. The rate of loss of hairs from non-woollen fabrics during normal wear was found to follow an exponential decay curve. In contrast, the rate of loss from the woollen garments was quite linear, indicating a constant, even loss, and thus suggests that a different process is involved in the persistence of hairs on woollen garments from that on non-woollen garments. The speed at which hair was lost from fabrics decreased in the order polyester, cotton/acrylic, polycotton, cotton, smooth wool, rough wool, so that wool gives the best chance of recovering samples of hair. Due to the uniqueness of each case, it is advised that caution be used when making any interpretations and before drawing any conclusions.

Fabric-staining properties and washability of a novel liposomal dithranol formulation

AIM: To test the staining potential of a novel liposomal dithranol gel on different types of fabrics and compare it with the only commercially available dithranol preparation in India, DerobinA. METHODS: Pure cotton, pure polyester and four blends of the two fabrics were tested for staining and washability. RESULTS : Both products showed the least staining and spreading on pure cotton with progressively worse stains as the proportion of polyester in the fabric increased. When compared with each other the liposomal dithranol gel showed markedly lighter staining than Derobin on all fabrics. It also washed off completely with water whereas the Derobin stains could not be washed off, even with detergent. CONCLUSION: The liposomal gel due to its superior staining properties may potentially increase the acceptability of dithranol amongst psoriasis patients.

Flame propagation in a tent camp

This paper presents an experimental study leading to the understanding and modelling of the effect of air speed and its direction on flame propagation in tent fabrics in addition to fire propagation in a tent camp. The study was conducted on burning fabrics of different densities subjected to wind speeds ranging between zero (stagnant) and 1.4 m s−1. Moreover, several air directions with respect to the flame were considered in the study to cover the cases of vertically upward, downward, horizontally aiding and opposing, and inclined directions. These cases were used in simulating actual flame propagation in a tent. It is found that there is a logarithmic relation between the time of burning a tent and air speed and the density of tent fabrics. Two different types of fabric are considered; waterproof and non-waterproof. It is also observed that the surface flame temperature is invariant with air speed or fabric density and it reaches about 650°C. The results show that denser fabrics require more time for burning. The maximum flame propagation speed is observed for vertically upward flame concurrent with air direction. On the other hand, minimum flame propagation is observed for vertically downward flames opposing the air direction. A model is derived for predicting the time required for flame propagation in a known camp area. Copyright © 2001 John Wiley & Sons, Ltd.

Compression in the processing of polymer composites 1. A mechanical and microstructural study for different glass fabrics and resins

This paper focuses on the compression of fibre reinforcements during the processing of polymer composites, covering a range of fabrics, namely a plain weave, a twill, a satin and a non-crimped, stitch-bonded fabric. The compression of assemblies of fabrics has been studied in both dry and wet states where, in the latter case, the fabrics were impregnated with three alternative resins: a non-Newtonian polyester of relatively high viscosity, a non-Newtonian polyester of relatively low viscosity, and a Newtonian epoxy of equally low viscosity. Investigations of mechanical behaviour included the influence of compression speed, type of fabric and viscosity and type of resin. Microstructural studies of laminates produced under different degrees of maximum compression elucidated further the results of mechanical compression and provided data of average area porosity (resin-rich areas), area pore structure, average area voidage and voids for the different types of fabrics.

Penetration of household insecticides through different types of textile fabrics

Six different types of fabrics were compared for their ability to protect against human exposure to three different commercial household aerosol insecticides. Fabrics used in this investigation were, 100% cotton, cotton-polyester thermal underwear, cotton-polyester blend (twill), 100% acrylic, 100% wool and artificial silk (rayon). The household insecticides were, Black Flag ®( Ant and Roach Killer), Raid ® (Ant and Roach Killer) and Hot Shot ®(Wasp and Hornet Killer) containing propoxur, permethrin/pyrethrins and chlorpyrifos/allethrins as their active ingredients respectively. A fluorescent tracer, 4-methyl-7-diethyl amino coumarin was mixed with the aerosol (or equivalent aliquot) and sprayed onto cloth squares fitted on Whatman paper patches . The percentage of penetration through the cloth was quantified by the intensity of the fluorescence spectrum of each patch extract and the amount of the tracer recovered was calculated. The extract was concentrated to 1 10 th of the volume to measure the content of each of the insecticides by supercritical fluid chromatography (SFC) using electron capture (ECD) and diode array detectors. Scanning electron microscope (SEM) images of the fabrics showed the geometry of the yarn. The results obtained from the fluorescence spectra, SFC and SEM showed that cotton-polyester (twill), cotton, wool and cotton thermal underwear were the least penetrable materials for the aerosols. On the other hand, acrylic and artificial silk (rayon) were the most penetrable cloth types.

Discussion of "Development of a microwave clothes dryer" [and reply

In the original paper (see ibid., vol. 32, p. 47-50, 1996), Kesselring and Smith presented several results regarding laboratory tests of a prototype of a microwave clothes dryer. For the three distinct operating modes (i.e., cool drying, fast drying, and efficient drying), the authors discuss how the microwave dryer compares to the performance of a standard electric dryer with respect to: (1) kWh consumption; and (2) noise level. Despite the lower drying temperatures obtained in the case of the microwave model, they question whether an assessment been made with respect to any eventual influence on the useful life of different types of fabrics. They also query whether a sample of prospective users surveyed about their opinions on the quality of the drying job and if the authors have new developments to present. They argue that a description of possible impacts on the urban/rural electrical distribution systems due to these future loads would also be valuable.

Microstructural features of high temperature shear zones in gabbros of the Northern Apennine Ophiolites

This paper presents preliminary data on the microstructural evolution of upper amphibolite facies mylonitic metagabbros from the Bracco Ophiolite Complex, Northern Apennines (Italy). High temperature deformation, possibly related to the initial stages of breakup and oceanization in the Ligurian Tethys, led to the development of three different types of fabrics in the coarse grained Mg-gabbros, the most widespread rock-type in this area. With progressive deformations, coarse-grained porphyroclastic mylonites (fabric type 1), banded (fabric type 2) and ‘flinty’ ultramylonites (fabric type 3) were formed. In plagioclase and clinopyroxene, the two main minerals in the studied rocks, optical microstructures and scanning electron microscopy analyses indicate crystal plasticity as the main deformation mechanism. A possible change from ‘rotation’-recrystallization regime, through grain boundary migration to diffusion-assisted high temperature grain boundary sliding, is suggested for the plagioclase grains in high temperature shear zones.

Effect of different types of textile fabric on spermatogenesis: electrostatic potentials generated on the surface of the human scrotum by wearing different types of fabric.

This study was conducted to evaluate the effect of the electrostatic potentials generated on the surface of the scrotal area when different types of textile fabric were worn. Twenty-one healthy volunteers were divided into three equal groups. The first group was dressed in underpants made of 100% polyester, the second wore underpants of 100% cotton, and the third wore a 50/50% polyester/cotton mixture. With an electrostatic kilovoltmeter, the electrostatic potentials were measured 1 h after wearing the pants once during the day and a second time at night. The test was repeated 4 times, each on a separate day. No electrostatic potentials were detected on the cotton underpants. The polyester pants showed the highest potentials (mean 338.9 +/- 25 SD V/cm2), while the mixed polyester/cotton pants produced less than half that level (mean 148.3 +/- 16 SD V/cm2). The readings during the day were higher than those at night, probably due to the higher temperature during the day. This study could explain the cause of diminished spermatogenesis in dogs dressed in polyester pants. A new theory is put forward holding that the polyester underpants create an "electrostatic field" across the scrotal sac that disturbs the testicular and/or epididymal function.

Automatic Manipulation of Fabric in the Czechoslovak Garment Industry

Examines the problems involved in mechanically lifting a cut piece of fabric from stacked layers, successfully separating the single piece, and transferring it to a precisely defined position. Grasping heads of four main types (or a combination) are commonly used: mechanical, pneumatic, adhesive and electrostatic. Describes experimental testing of mechanical heads operating with needles for different types of fabrics. Additional equipment (brushes on the edge of the cut fabric layer) always increased taking‐off reliability, as did additional pressure plates up to a certain mass.

Effect of Fabric Washing on the Presumptive Identification of Bloodstains

The purpose of this study was to investigate the retention of blood stains on twelve different types of fabrics after washing at various drying times. The findings of this study, supported by chi-square analysis, indicate that the retention of bloodstains on washed fabrics depends upon the particular fiber composition of the fabric, the specific blood screening test used, and whether or not a detergent was used in the wash. The results of this research did not reveal a significant effect of the drying time on the retention of bloodstains, as tested during the 48-h limit of this experiment. The author concludes that the forensic serologist should consider the factors investigated in this study before rendering an opinion on the retention of bloodstains on washed garments.

Reinforced Substrates: Aerospace Technology Introduces a New Concept for Industrial Fabrics

The purpose of this research and development project was to determine if an engineered system of reinforcing substrates as developed by aerospace technology is adaptable to industrial fabrics. The creation of an entirely new breed of industrial fabrics, however, also requires solid, demonstrative proof that such fabrics will satisfy an existing need better than existing materials and practices or introduce fabricators and manufacturers to an entirely new market. Very thin films used in commercial and space aircraft for insulation covering require effective reinforcement both for fabrication and strength purposes. To keep weight at a minimum, a reinforcing system of bonded, oriented, and continuous strand yarns was developed. In this system the fill yarns are coated with an adhesive, passed over the warp, and bonded to a substrate in a continuous procedure. Fill yarn spacing is variable at will. Virtually any size, type, and combination of yarns can be used. Adhesives are selected to match the end use of the reinforced product. As a part of the project, this reinforcing system was applied to many types of plastic films and to both woven and non-woven substrates. Laboratory and field work on this project began in August 1976. Over 400 different types of fabrics were constructed and evaluated for possible use in approximately 60 industrial applications.