Wicking fabrics

Manufacturers are also redesigning the interior of welding gloves. A variety of linings — such as moisture wicking fabrics, channeled foam and aluminized materials — are incorporated to provide heightened protection and enhance user comfort. 

Since fungi thrive in warm, moist environments, the practitioner should encourage patients to wear loose-fitting clothing and socks, preferably garments made of cotton or other fabrics that wick moisture away from the body. Avoid clothing made with synthetic fibers or wool. 

One instrument for determining the relative humidity of the atmosphere. It consists of a pair of thermometers, the bulb of one of which is surrounded by a fabric wick kept moist from a small water reservoir. Due to evaporation the temperature indicated by the wet bulb thermometer is lower than that of the other. The difference in the readings compared to the dry bulb reading enables the relative humidity to be obtained from tables. 

Aravamudhan, Rahman, and Bhansali. [70] developed a micro direct ethanol fuel cell with silicon diffusion layers. Each silicon substrate had a number of straight micropores or holes that were formed using microelec-tromechanical system (MEMS) fabrication techniques. The pores acted both as microcapillaries/wicking structures and as built-in fuel reservoirs. The capillary action of the microperforations pumps the fuel toward the reaction sites located at the CL. Again, the size and pattern of these perforations could be modified depending on the desired properties or parameters. Lee and Chuang [71] also used a silicon substrate and machined microperforations and microchannels on it in order to use it as the cathode diffusion layer and FF channel plate in a micro-PEMFC. 

The behavior of liquids in narrow tubes is one of the most common examples in which capillary forces are involved. It will be shown later how important this phenomenon is in many different parts of everyday life and technology. In fact, liquid curvature is one of the most important physical surface properties that requires attention in most of the application areas of this science. The range of these applications is from blood flow in the veins to oil recovery in the reservoir. Properties of fabrics are also governed by capillary forces (i.e., wetting, etc.). The sponge absorbs water or other fluids where the capillary forces push the fluid into the many pores of the sponge. This is also called wicking process (as in candlewicks). 

The luminol detector is based on the sensitive chemiluminescent reaction between N02 and luminol in solution. The luminol in alkaline solution reacts with N02 to produce intensive CL centred on 425 nm. The detector cell itself is a 15 cm x 8 cm x 2 cm rectangular block, with inlets and outlets for the carrier gas and luminol flows. The reaction cell contains a fabric wick that is wetted with the luminol solution (1 x 10-4M luminol, 0.2MNa2SO3, 0.05M NaOH, 1.5 x 10 4 ethylenediaminetetraacetic acid and 0.1% surfactant). The wick is viewed by a PMT through an acrylic window, which is transparent to the chemiluminescent light at 425 nm. When a N02 peak enters the cell, a fraction of the N02 dissolves in the solution on the surface of the wick, which then reacts with luminol to ultimately yield a strong CL. The results described indicate that this detector may be successfully used for the sensitive and selective detection of any nitrogen-containing species that may thermally decompose to yield N02, with a potential use for the detection of explosives (2,4-DNT and TNT). 

It is important that individual fibers be used rather than yams, batts, or fabrics. Such assemblages of fibers interact with liquids by wicking, a phenomenon which depends as much on geometrical factors as on the CST of the fiber surface. The present method is thus sharply distinguished from those utilizing fiber assemblages (I, 3). 

Many film adhesives have a supporting carrier or reinforcement fabric incorporated into the adhesive to improve handling of the film and provide control of bond line thickness. The carriers are usually glass, polyester, or nylon fabrics of knitted, woven, or nonwoven construction. The difficulty with such carriers is that they can provide an effective way of moisture entering the bulk of the adhesive. Moisture can wick along the fiber-adhesive interface. Nylon carriers should especially be reviewed since they have a strong tendency to absorb moisture. 

Compare the molecular stmetures of cotton and polypropylene, the two major components of thermal underwear. One of these gets wet easily and holds the water in contact with the skin. The other one does not get wet, but wicks the water away from the skin and feels relatively dry to the touch. Explain the difference in how these two fabrics respond to moisture. 

Providing flame retardancy for fibre blends has proved to be a difficult task. Fibre blends, especially blends of natural fibres with synthetic fibres, usually exhibit a flammability that is worse than that of either component alone. Natural fibres develop a great deal of char during pyrolysis, whereas synthetic fibres often melt and drip when heated. This combination of thermal properties in a fabric made from a fibre blend results in a situation where the melted synthetic material is held in the contact with the heat source by the charred natural fibre. The natural fibre char acts as a candle wick for the molten synthetic material, allowing it to bum readily. This can be demonstrated by the LOl values of cotton (18-19), polyester (20-21) and a 50/50 blend of both (LOl 18), indicating ahigher flammability of the blend as described later (Section 8.11). But a rare case of the opposite behaviour is also known (modacrylic fibres with LOl 33 and cotton in blends from 40-60 % can raise the LOl to 35). 

Scenario Simmons Bedding Company unveiled its latest innovation, the HealthSmart bed, featuring a zip-off mattress top that may be laundered or dry cleaned. Its coolmax-channeled fibers wick away sweat and moisture as you sleep, and allow the fabric to dry quickly in the laundry. In the second layer, Nano-Tex (nano technology) creates a semi imperwious layer that traps fluids and particles so they can be washed away. The third layer is terry cloth treated with Teflon fabric protector that provides an extra level of protection. 

It is specifically recommended for use in resin systems when the fabric is to be printed after finishing to prevent wicking or flushing of the colors. It is not recommended for use, across the board, for all finishing operations since it is known to cause shade change of vat blues on curing. 

Quaternary compound. High purity, long chain quaternary ammonium compound used with caustic to improve fabric wicking characteristics, reduce pilling on polyester and to obtain anti-static properties on triacetate fabrics. Used to remove polyvinyl acetate and other resin esters from fabrics. 

Excellent softener for toweling and other specialty fabrics. Provides good wicking and fast rewetting properties non-yellowing--fatty amide blend. 

These devices are used to apply contact or translocated (systemic) herbicides selectively to weeds in crop areas. Wicks made of rope, rollers made of carpet or other material, or absorbent pads made of sponges or fabric are kept wet with a concentrated mixture of contact herbicide and water and brought into direct contact with weeds. The herbicide is "wiped" onto the weeds but does not come in contact with the crop. Application may be to tall weeds growing above the crop or to lower weeds between rows, depending on the way the wiper elements are designed. Pumps, control devices, and nozzles are minimal or are eliminated altogether, and tanks are quite small because of the small amount of liquid applied. 

The intrinsic affinity of fibers for water is easily quantified by measuring the sinking time of a piece of fabric carefully deposited on water. A better alternative is the dye wicking method in which a fabric strip is suspended with the extremity dipping in a 0.05% aqueous solution of methylene blue. The rise of the liquid is recorded as a function of time and compared to that of a control without softener. 

In such a case, the wicking characteristics, which determines how quickly and how widely liquid water spreads out laterally on the surface of or within the matrix of the fabric, determines the overall water vapour transport rate through the layered fabrics. 

It was also found that properties relevant to clothing on an exercising person, that is, the energy required to evaporated water from under and through a dry fabric or to dry a wet fabric and layer-to-layer wicking [60]. 

These two problems—noncondensible gas generation and corrosion—are only two of the factors to be considered when selecting heat pipe wicks and working fluids. Others include wettability of the fluid-wick combination, strength-to-weight ratio, thermal conductivity and stability, and cost of fabrication. 

No attempt has been made in this chapter to measure wicking and to correlate it directly with microviscosities, because the kinetics of sorption may be complicated by difiusion of liquid into the fibers rather than capillary movement between fibers (13). In a real printing operation, the fixation conditions and rate of drying of the print, the type of fabric used and its thickness, the twist of the yams, and the type of fibers used have a strong influence on wicking behavior (11). 

PL A fabrics exhibit the comfort and touch of natural fibres such as cotton, silk and wool while having the performance, cost, and easy care characteristics of synthetics. PLA fibres demonstrate excellent resiliency, outstanding crimp retention and improved wicking compared with natural fibres. Fabrics produced from PLA are being utilized for their silky feel, drape, durability and water vapour permeability used to create breathability suitable for sport clothing applications [195]. 

Wicking. The liner fabric should not wick or delaminate (if laminated) if a raw edge is exposed to saturated brine at up to 100 deg C. (standards need to be set on this). 

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