bluuebunny/crossref_metadata_2025 huggingface dataset:
Water Absorption and Mechanical Properties of Pile-Knit Fabrics Based on Conjugate N/P Microfibers
Authors: Seong Hun Kim  , Seong Joo Kim  , Kyung Wha Oh
Published: March 2008

The effect of chemical splitting on the water absorption and mechanical properties of a split-type nylon/polyester (N/P) microfiber pile knit is investigated under various alkaline hydrolysis treatment conditions. Weight loss of the hydrolyzed pile knit increases as hydrolysis time, temperature, and concentration of sodium hydroxide increase. Areal density decreases with increased weight loss. Maximum water absorption (%) is 28.1 % of weight loss. In terms of mechanical properties measured by KES-FB, deformation of the shape of the knit is easy due to decreased tensile strength. Bending and shearing values diminish, which leads to increased drapability and flexibility. Surface properties vary with changes in weight loss. The morphological study reveals that the fineness of the split polyester microfibers decreases with increased weight loss.
Simultaneous Heat and Moisture Transfer with Moisture Sorption, Condensation, and Capillary Liquid Diffusion in Porous Textiles
Authors: Yi Li  , Qingyong Zhu
Published: March 2008

A dynamic model of liquid water transfer coupled with moisture sorption, condensa tion, and heat transfer in porous textiles is developed by incorporating the physical mechanism of liquid diffusion in porous textiles into a coupled heat and moisture transfer model developed previously. An equation describing liquid diffusion behavior is devel oped in the form of the diffusion coefficient, and a numerical computational scheme to solve the coupled equations involves a fractional volume of fluid method. Experiments measuring fabric surface temperature are conducted to validate the model, and there is reasonable agreement between the predictions and the measurements.
Practical Engineering Calculations for Working Cylinders on Carding Machines
Authors: Stadnicki Jacek , Wrobel Ireneusz
Published: March 2008

Textile engineering processes require increased accuracy of the carding machines' working cylinders. In engineering calculations for designing the cylinders, the models should take into account flexibility and joint type. Moreover, the tolerances of manufac turing the component parts of the cylinders should be tighter. A continuous model and a discrete (finite element model) model that consider these factors of the working cylinder are presented in this paper. The results of the model analyses are compared with experimental measurements.
Deformation Analysis of 3D Braided Structural Composites
Authors: Tang Zheng-Xue , Postle Ron
Published: March 2008

A nonlinear finite element technique is used to simulate and analyze the deformation behavior of 3D braided composites. The finite element displacement formula is derived from the geometric nonlinear behavior of braided composites. The integral relevant to the element stiffness matrix is simplified by selecting a 20-node hexahedral solid element. The Gauss-Legendre quadrature is used to compute the element matrix. A program referred to as SNLFEDA (Simulation of Nonlinear Finite Element Deformation Analysis) is developed. Tension, compression, and bending of 3D braided composites is simulated, and the results' of these simulations are supported by the experimental data and the values predicted by previously published elastic modulus models.
Effects of Mold Porosity on Fiber Distribution in a 3D Nonwoven Process
Authors: Ravirala N. , Gong R.H.
Published: March 2008

3D nonwovens can be formed using the air-laying principle. The fibers are deposited onto a porous mold and the web is then consolidated. Distribution of the fibers on the 3D mold must be regulated to produce a final product with the desired fabric evenness. This can largely be achieved by varying the local mold porosity. CFD modeling is used to calculate the required porosity in different regions of the mold in order to achieve an even fiber distribution, and the results are experimentally validated.
Weathering of Polyaniline-Treated Polyester Filter Fabrics
Authors: Järvinen Kimmo , Puolakka Arja
Published: March 2008

During shipping and storage operations, a filter medium may be subjected to UV light, cold, humidity, and even direct wetting. Hence, it is of utmost importance that the medium and semi-finished fabric is tested against all foreseeable stresses it may encounter before it reaches its final destination. In this work, polyaniline-treated polyester filter fabrics are subjected to an intensive water shower, humidity, cold, and ultraviolet light on a labora tory scale. Weathered fabrics are measured before and after weathering for electrical resistivity in both the lateral and pass-through directions. The results indicate that polyaniline-treated woven polyester fabrics have good tolerance for all tested conditions, and electrical resistance is not significantly affected by weathering.
Structural Characteristics of New and Conventional Regenerated Cellulosic Fibers
Authors: Kreze Tatjana , Malej Sonja
Published: March 2008

Comparative investigations of the new lyocell and conventional viscose and modal fibers attempt to explain the reasons for differences in the molecular and fine structure of these fibers. This research is a systematic analysis of structural characteristics (molecular and fine structure) and their influence on fiber properties. The analysis shows that lyocell fibers consist of longer molecules, they have a greater degree of crystallinity, their slighter but rather longer crystallites are oriented in the fiber axis direction, and their void structure is similar to that of viscose fibers. Differences in the molecular and fine structure of these fibers cause different mechanical and sorption properties. Good mechanical properties are a function of the structure of lyocell fibers, especially with the highest orientation factor and crystallinity index. Sorption properties place lyocell fibers somewhere between viscose and modal fibers. Our results demonstrate that the adsorption properties of cellulosic fibers depend, except for the less ordered amorphous regions, predominantly on the void fraction.
Simulating the Flow Dynamics in Hydroentangling Nozzles: Effect of Cone Angle and Nozzle Aspect Ratio
Authors: Tafreshi H. Vahedi , Pourdeyhimi B.
Published: March 2008

Flow behavior in various nozzle shapes from the hydroentangling cone-capillary family is modeled in this paper. The work studies the effects of cone angle and nozzle aspect ratio (the ratio of the capillary section to its diameter) on water-jet formation. In particular, two sets of nozzles are considered. The first set consists of nozzles that have an aspect ratio of one and cone angles of 19, 15, 11, 7, and 3°, respectively. The nozzles in the second set have their inlet and outlet diameters fixed, but their aspect ratios vary from 1 to 6. The results from a two-phase axisymmetric steady-state model of turbulent nozzle flow reveal that decreasing the cone angle or increasing the nozzle aspect ratio does not affect the hydroentangling water-jet characteristics. The computational scheme is validated by comparing part of the results with the available experimental data in the literature.
An Energy Model of Plain Knitted Fabric
Authors: Choi K.F. , Lo T.Y.
Published: March 2008

A new mathematical model describing a plain knitted fabric is proposed in this paper. One major feature of this model is that the yarn in the fabric can be naturally curved with nonlinear mechanical properties. The new model is able to describe the dimensions and also the low stress mechanical properties of a plain knit. Based on an energy analysis, the inadequacy of the classic k-values is explained. Complex dimensional behavior and problems associated with relaxation of knitted fabric are discussed. A more precise prediction of fabric dimensions is possible by including the degree of set as one of the parameters. The paper also explains why most of the studies of knitted fabric dimensional properties in the past have been empirical.
Experiment and Analysis of Combined Heat and Water Vapor Transfer Through Clothes with Condensation
Authors: Fukazawa T. , Kawamura H. , Tochihara Y. , Tamura T.
Published: March 2008

A series of experiments is performed on the combined heat and water vapor transfer through fabric at simulated high altitudes. A considerable water vapor concentration difference is imposed between the water vapor source and the environment, so that condensation takes place in the specimen. A new analytical expression for the rate of condensation in textile materials is derived by considering the combined heat and mass transfer between the specimen and the environment. Although the amount of condensation in textiles can not be correlated well by primitive parameters such as temperature or water vapor concentration differences, good agreement can be obtained between the condensa tion mass flux measured experimentally and that calculated by means of the derived expression.
Drafting Force of Twin Spun Yarn
Authors: Su Ching-Iuan , Liu Chih-Hsiang , Jiang Jau-Yuan
Published: March 2008

To determine the optimum drafting conditions of twin spun yam spinning, the drafting force must be investigated. In this work, we conduct a drafting force experiment based on Lyocell twin roving of to investigate the influence of the roller gauge, draft ratio, and roving spacing. The experimental results show that the drafting force of the Lyocell twin roving has a high value with a wider plateau. In addition, twin roving spacing affects drafting behavior. Consequently, the 1.2 break draft ratio and 54 mm back roller gauge corresponding to 10 mm roving spacing used in conjunction with 1.2 denier Lyocell roving of 120g/30yd are the optimum conditions to obtain the best yarn quality for 19.7 tex twin spun yams.
Variations in Sensibility to Fabric Frictional Sound by Fiber Type and Subject
Authors: Na Youngjoo , Cho Gilsoo
Published: March 2008

We have investigated sensation responses to fabric frictional sounds according to fiber type, subject's nationality, age, gender, and acoustic sensitivity. Twenty-six American and thirty- two Korean adults participated in this study, and answered questions on seventeen adjectives describing sensations upon hearing the frictional sounds of eight fabrics, including "feeling good," "harsh to ear," "sharp," "deep," "loud," and "strong," etc. The structural concept of sound sensation has four dimensions: "height," "feeling good," "dimension," and "rustling." Americans identified the sound of wool fabric better than Koreans, while Koreans identified the sound of silk fabric better than Americans. The percent contributions of five variables of subject and fiber type to each sound sensation were calculated by ANOVA. Fiber type affected the four sound sensations most, followed by the subject's age and nationality. Other variables were hearing sensitivity and subject's gender.
Influence of Varying Structural Parameters on the Properties of 50/50 Wool/Polyester Blended Fabrics
Authors: Önder Emel , Kalao Fatma , Özipek Bülent
Published: March 2008

This paper deals with the mechanical properties and air permeability of lightweight wool blend apparel fabrics. We have studied mechanical responses in uniaxial tensile and tear tests of gray-state fabrics, and low deformation characteristics (i.e., bending rigidity, shear rigidity, and extensibility) in FAST tests of finished fabrics. We also measure fabric drape coefficients and node numbers using Cusick's method and fabric air permeabilities. Effects obtained by changing polyester and yarn type are analyzed for three groups of fabrics with different constructions using a statistical approach and are found to be significant; however, using novel polyester with a special cross-sectional shape and varying fineness in the wool blend, we successfully obtain fabrics with low rigidities, better drape characteristics, and quite sufficient tensile and tear performance. The behavior of fabrics woven with Sirospun yams is quite satisfactory in many respects. Polyester and yarn type also significantly affect fabric air permeability.
Effect of Gray Fabric Properties on Flame Resistance of Knitted Fabric
Authors: Ozcan Gulay , Dayioglu Habip , Candan Cevza
Published: March 2008

In this study, knitted fabrics that have been used extensively in recent years are chosen to investigate the effects of their properties on flame resistance. Physical parameters (fiber type and composition, yarn count, yarn twist coefficient, fabric design, weight per unit area, air permeability, fabric thickness, cover factor, loop density) that affect fabric flammability are defined and an experimental study is designed. The burning behavior of the all fabrics is evaluated using the BS 5438 vertical flammability test method because its results are very similar to real fabric burning behavior and it is more responsive than other test methods. Finally, experimental results are evaluated according to a MANOVA analysis using an SPSS statistical program. How and at which level knitted fabric param eters affect a fabric's burning behavior is defined, and regression models of these parameters are obtained. Using these regression models, the burning behavior of knitted fabrics is evaluated, and it is possible to rank them according to their burning character istics.
Modifying Dew-Retted Flax Fibers and Yarns with a Secondary Enzymatic Treatment
Authors: Evans Jeff D. , Akin Danny E. , Morrison W. Herbert , Himmelsbach David S. , Mcalister David D. , Foulk Jonn A.
Published: March 2008

Preliminary studies by atomization test the application of various kinds of enzymes as a means of tailoring dew-retted flax fibers in a low moisture atmosphere. A series of chemical and physical tests determines the effect of enzymes on fibers and blended yarns (50:50 flax : cotton). GLC analysis of post-treatment fiber washes shows that lipase and cellulase release the most sugars, likely due to structural disorganization of the fiber matrix. Glucose is the sugar most released by enzyme treatment. Mid-infrared spectros copy of fibers indicates the loss of carbohydrates and the presence of absorbed proteins following all enzyme treatments. All treatments reduce fiber strength and elongation compared to untreated fibers, with cellulase reducing fiber strength the most at 56% of the untreated control. Treatments reduce the occurrence of thick and thin places but reduce yarn strength as well. In general, lipase and arabinanase treatments influence yarn properties the most by increasing strength over the buffer-only treatment, increasing elongation over untreated and buffer-treated yams, and reducing neps and thick/thin places. These preliminary results suggest strategies to optimize enzyme treatments for improved textile properties.
Determining an Optimum Opening Roller Speed for Spinning Polyester/ Waste Blend Rotor Yarns
Authors: Duru Pinar N. , Babaarslan Osman
Published: March 2008

The opening roller, which is one of the three most important items in the OE rotor spinning system, influences yarn quality and spinning performance. In addition to the raw materials, roller speed and type are critical. In this work, seven different polyester/waste (cotton noil, recycled fibers, flat waste, etc.) rotor yams are produced at seven different opening roller speeds on a laboratory-type OE rotor spinning machine (Quickspin), and the influence of opening roller speed on yarn quality is examined. A high opening roller speed is recommended, while spinning waste content does not provide the expected results.
Noncellulosic Constituents on Raw Cotton and Their Relationship to Fiber Physical Properties
Authors: Brushwood Donald E.
Published: March 2008

Raw cottons contain a number of noncellulosic materials that are generally considered to be surface related and may therefore affect fiber quality. Chemical tests are conducted on cottons originating from different U.S. growing locations to determine reducing sugars, wax, metal contents, and total alcohol extractable materials. Relationships between concentrations of these constituents and conventional fiber physical property measure ments are investigated. Increases in HVI and Stelometer fiber strength and RotorRing fiber-to-fiber friction and decreases in Suter-Webb short fiber content are highly related to increases in alcohol extractable materials, fiber ash residues, and total light metal contents. Conversely, increases in the metal calcium correlate with decreases in both fiber strength and fiber-to-fiber friction and increases in short fiber content. Increases in HVI Rd and + b color measurements correlate positively with increasing levels of the metals potassium and magnesium.
Modeling Permeability in Homogeneous Three-Dimensional Nonwoven Fabrics
Authors: Mao N. , Russell S.J.
Published: March 2008

A simplified three-dimensional structural model for a series of nonwoven fabrics is presented. The corresponding directional permeabilities of the fabrics are calculated based on the measured two-dimensional fiber orientation distribution. The influences of fiber diameter, fabric porosity, and fiber orientation distribution on the directional permeabili ties are considered.
Effect of Yarn Hairiness on Energy Consumption in Rotating a Ring-Spun Yarn Package
Authors: Lingli Chang  , Tang Zheng-Xue , Xungai Wang
Published: March 2008

The effect of yarn hairiness on energy consumption when rotating a ring-spun yarn package is investigated theoretically and experimentally. A theoretical model is developed to calculate the energy required to rotate hair fibers, based on hair length and number as well as package speed and size. A single spindle test rig is used to verify the theoretical prediction. The experimental results confirm the theoretical prediction that the package power increases with increased yarn hairiness level and spindle speed.
Structural Characterization and Properties of Lyocell Fibers After Fibrillation and Enzymatic Defibrillation Finishing Treatments
Authors: Carrillo F. , Colom X. , Valldeperas J. , Evans D. , Huson M. , Church J.
Published: March 2008

The mechanical, structural, and dyeing properties of solvent-spun lyocell fibers in a plain weave fabric are studied before and after industrial treatments of mechanical fibrillation and enzymatic defibrillation. Stress-strain relationships, surface morphology, crystallinity, and dye uptake are assessed for each of the samples and compared. Both treatments significantly decrease the tensile failure properties of the yarns. There are no appreciable changes in the Young's modulus, nor are there significant differences in yarn linear density or fiber diameter. Fourier transform infrared spectroscopy and x-ray diffraction results identify the crystalline morphology of the lyocell fibers as cellulose II. Spectroscopy results indicate that a small decrease in crystallinity takes place with industrial processing. The rate of decreased fiber crystallinity during ball milling is facilitated by the fibrillation and enzymatic treatments. Compared to the untreated fabric, both treated fabrics exhibit increased dye uptake rates, which appear to be greatest after fibrillation.
Cellulase Treatment of Durable Press Finished Cotton Fabric: Effects on Fabric Strength, Abrasion Resistance, and Handle
Authors: Yang Charles Q. , Zhou Wenlong , Lickfield Gary C. , Parachura Krishna
Published: March 2008

Enzyme washing is commonly used as a wet process technique to improve textile handle, appearance, and other surface characteristics of cottons in the industry. In this research, we have studied the effects of cellulase treatment on tensile strength, flex abrasion resistance, and handle of cotton fabric crosslinked by a polycarboxylic acid. The fabric is first treated with cellulase (pre-curing treatment), then crosslinked by 1,2,3,4- butanetetracarboxylic acid (BTCA). The fabric is also crosslinked by BTCA first then treated with cellulase (post-curing treatment). We compare the performance of the durable press (DP) finished cottons treated with cellulase using these two different procedures, and we find that the pre-curing cellulase treatment has a more positive influence on fabric handle than the post-curing treatment, but it also causes significantly higher fabric strength loss than the post-curing treatment. We also find that the difference in wrinkle resistance of the DP finished cotton fabrics with the two treatments is not significant. Considering the fact that a DP finishing process reduces fabric strength, the pre-curing cellulase treatment method should be used only for heavy cotton fabrics with high original strength.
Estimating Single Cotton Fiber Tensile Properties from the Load-Elongation Curves of Slack Bundles
Authors: Cui Xiaoliang , Suh Moon W. , Sasser Preston E.
Published: March 2008

A method has been developed to estimate single cotton fiber tensile properties from load-elongation curves of slack fiber bundles. The method is applied to bundle load- elongation curves from HVI tests to estimate the averages of fiber breaking strength, elongation, and crimp. The estimated values are compared with single fiber tensile properties obtained from a Mantis® single fiber tester.
Frictional Behavior of Synthetic Yarns During Processing
Authors: Lang Jun , Zhu Sukang , Pan Ning
Published: March 2008

The frictional behavior of synthetic yams during various textile processes is investi gated in this paper. The main advance of this work over previous research is that the deformation of the oil film lubricating the fibers is taken into consideration. The thickness of the oil film decreases due to pressure, which causes changes in the friction mechanism. To account for the transition, the effective hydrodynamic friction length during the process is defined, calculated, and discussed in this paper. The theoretical results can be used to validate and explain the findings from existing experiments made available by other researchers.
Simulating Anisotropic Woven Fabric Deformation with a New Particle Model
Authors: Dai Xiaoqun , Li YI , Zhang Xin
Published: March 2008

This paper reports the development of a new particle model to simulate fabric mechan ical behavior. A particle model of square meshes, which is close to the orthotropic structure of a woven fabric, is used to represent the fabric. In addition to the separation, bending, and shearing springs, a twist spring is introduced into the particle model to simulate the tension/compression, bending, shearing, and twisting behavior of the fabric. The forces and torques acting on the springs are derived according to fundamental elasticity mechanical laws. Experiments of the heart-loop test involving various fabric behaviors are conducted to validate the model. Comparisons between heart loops gener ated by the model and corresponding actual experimental results verify that the model is able to simulate fabric mechanical behavior with satisfactory accuracy. The anisotropy of woven fabric is shown by different heart loops formed by specimens in different direc tions, and is illustrated by the distributions of various inner stresses.
Dyeing Chitin/Cellulose Composite Fibers with Reactive Dyes
Authors: Shimizu Yoshiaki , Dohmyou Mihoko , Yoshikawa Masatoshi , Takagishi Toru
Published: March 2008

The dyeing properties of chitin/cellulose composite fibers—Crabyon® (CR)—for four reactive dyes are examined and compared with those of viscose rayon and partially deacetylated chitin. The CR fibers show high fixation for dyeing with CI Reactive Blue 5 with a monochlorotriazinyl group in a weakly acidic solution and with CI Reactive Blue 19 with a sulfatoethylsulfonyl group from weakly acidic to weakly alkaline solutions. The CR fibers can be dyed with CI Reactive Blue 19 in wide pH ranges, compared with viscose rayon, which cannot be dyed at these same pH ranges.
Effect of Crystal Melting on Water Vapor Permeability of Shape-Memory Polyurethane Film
Authors: Ding X.M. , Hu J.L. , Tao X.M.
Published: March 2008

Crystal melting of shape memory polyurethane (SMPU) film is investigated using polarizing optical microscopy, scanning electron microscopy, differential scanning calorimetry, and temperature variable wide-angle x-ray diffractometry. Water vapor permeability (wvp) at different temperatures is measured. The results show that the SMPU film is dense with crystalline soft segments. Crystal melting of soft segments takes place when the temperature increases from 10 to 50°C. At the same temperature range, the wvp of SMPU film increases significantly. After investigating the relationship between the relative changes in amorphous area and temperature, we can conclude that crystal melting of soft segments leads to increases in the amorphous area, resulting in a significant increase in water vapor permeability.
Determining the Surface Free Energy of Cellulose Materials with the Powder Contact Angle Method
Authors: Peršin Zdenka , Stana-Kleinschek Karin , Sfiligoj-Smole Majda , Kre Tatjana , Ribitsch Volker
Published: March 2008

Different treatment processes such as alkaline washing, bleaching, and slack-mercer ization are used to improve the sorption characteristics of cellulose fibers. The differences between the sorption properties of cellulose fibers are measured with tensiometry, and their sorption velocities are measured with liquids of different polarities. From those measurements, contact angles are determined using the Washburn equation. The surface free energy of the cellulose fibers is determined from contact angle data obtained with the Owens-Wendt-Rabel-Kaeble approximation. Results show that among these treatments, slack-mercerization produces the lowest contact angle and the highest surface free fiber energy, and has therefore the largest influence on sorption ability. Viscose fibers (raw and treated) have the lowest contact angle and the highest surface free energy, and are the most hydrophilic compared to lyocell and modal fibers. This is explained by their crystalline structure and the accessibility of their surface groups to polar liquids.
Improving the Color Yield of Ink-Jet Printing on Cationized Cotton
Authors: Chen Weiguo , Zhao Shichao , Wang Xungai
Published: March 2008

This study examines the performance of digital ink-jet printing on cationized cotton treated with polyepichlorohydrin-dimethylamine (PECH-amine). The results show that the color yield of ink-jet printing with reactive inks on cationic modified cotton is much greater than that on untreated cotton. The effect on the increase of color yield by cationic modification is greater than that by preparation with alkali, urea, and thickener. The reason for this is that introducing positively charged sites increases dye uptake and dye fixation on cationized cotton. The results also show that cationic modification with PECH-amine decreases the rub fastness but increases the wash fastness of the treated cotton.
Chemical Finishing of Bast Fibers and Woods Using Hydrolyzed Keratin from Waste Wool or Down
Authors: Kawahara Yutaka , Endo Rie , Kimura Teruo
Published: March 2008

Chemical treatments using hydrolyzed keratin from waste wool or down are effective for enhancing the tensile properties of bast fibers. Treatment with hydrolyzed down keratin is also useful for suppressing shrinkage in the course of drying waterlogged archaeological wood excavated from sites. This novel treatment shows some degree of probable use for conservation treatments of such waterlogged woods.
Automatic Recognition of Fabric Weave Patterns by a Fuzzy C-Means Clustering Method
Authors: Kuo  , Shih Chung-Yang , Lee Jiunn-Yih
Published: March 2008

A new robust recognition algorithm is proposed for fabric weave pattern recognition. The gray-level images of solid woven fabrics are captured by a color scanner and converted into digital files, then enhanced images are obtained by a gray-level morpho logical operation. Based on the interstices of yarns, warp and weft crossed areas are located, and four texture features of these areas are obtained by first-order and second- order statistics. Unsupervised decision rules for recognizing warp and weft floats are developed using a fuzzy c-means clustering method. The experimental materials include plain, twill, and satin woven fabrics. Experimental results demonstrate that three basic weave patterns can be clearly identified.
Modeling the Effects of Filament Radius and Photochemical Dye Fading on the Perceived Color Depth of a Filament Array
Authors: Broadbent Arthur D. , Capistran Serge , Motamedian Farid
Published: March 2008

An optical model is used for simulating the effects of varying filament radii on the perceived color strength of an array of parallel filament layers representing a textile fabric. As the filament radius decreases, the color yield also decreases in direct proportion. The model predicts that the concentration of dye in the filaments, required to achieve a given color strength, is inversely proportional to the filament radius in agreement with practical experience in dyeing microfiber fabrics. New equations are also derived to calculate the light absorption by each individual filament layer at a given dye concentration. The degree of photochemical dye fading in each layer is simulated using these respective absorbed light intensities leading to a decrease in the overall color strength. Repeated calculations of the absorbed light intensities and decreasing dye concentration and color strength show that pale colors will fade more rapidly than deep colors and that fading will be faster when the filament radius is decreased. Both these results agree with practical observations of the light fastness of dyeings. For deep colors, the upper filament layers absorb all the incident light, and filaments in the center of the array undergo minimal fading, resulting in significant dye concentration gradients in the filament matrix.
Numerical Simulation of Fiber Motion in the Nozzle of an Air-Jet Spinning Machine
Authors: Zeng Y.C. , Yu C.W.
Published: March 2008

A two-phase flow model is developed to simulate the fiber motion in the nozzle of an air-jet spinning machine. The computational results coincide with the images captured by high-speed photography. Three parameters, the first nozzle pressure, the jet orifice angle, and fiber flexural rigidity, are discussed in terms of their influences on wrapper formation and, consequently, on yarn structure and yarn quality. The predictions of yarn tensile properties tally with the experimental results reported by several researchers.
Contribution of Core and Sheath Components to the Tensile Properties of DREF-III Yarn
Authors: Das A. , Ishtiaque S.M. , Yadav P.
Published: March 2008

The contribution of individual core and sheath components to the tensile properties of DREF-III yarn is reported here. Three different yarn types are made by the DREF-III system: staple viscose fibers in both core and sheath, staple viscose fibers in the core and staple PVA fibers in the sheath, and staple PVA fibers in the core and staple viscose fibers in the sheath. Because PVA fibers are soluble in water, they are removed afterwards with boiling water to produce individual core and sheath components. In all samples, the core-sheath ratio is kept at 50:50. The parameters discussed here are the core contribution factor, the sheath contribution factor, the core-sheath interaction factor, and various other structure- related parameters such as yarn diameter, helix angle, helix diameter, and mean fiber extent. Process variables are the spinning drum speed and the yarn delivery rate. The paper reports the effects of these process variables on tensile properties of the parent DREF-III yarn as well as individual core and sheath components. Structural changes due to removal of either core or sheath are also reported.
Evaluating the Robustness of Objective Pilling Classification with the Two- Dimensional Discrete Wavelet Transform
Authors: Palmer Stuart , Xungai Wang
Published: March 2008

Previously, we proposed a new method of frequency domain analysis based on the two-dimensional discrete wavelet transform to objectively measure pilling intensity in sample fabric images. We have further evaluated this method, and our results indicate that it is robust to small horizontal and/or vertical translations and to significant variations in the brightness of the image under analysis, and is sensitive to rotation and to dilation of the image. These results suggest that as long as precautions are taken to ensure fabric test samples are imaged under consistent conditions of weave/knit pattern alignment (rotation) and apparent interyarn pitch (dilation), the method will yield repeatable results.
Investigating the Drape Behavior of Seamed Knit Fabrics with Image Analysis
Authors: Uçar Nuray , Kalaočlu Fatma , Bahtiyar Duygu , Blaç Ozan Emre
Published: March 2008

Drape is one of the most important fabric aesthetic properties. Although there are many studies related to the drape structure of seamless fabrics, knowledge about the drape behavior of seamed fabrics is very limited. This study analyzes the effect of five-thread overlock seams (stitch type 516, seam type Ssa-1) on the drape behavior of heavy weight knit fabrics to provide prediction equations for drape. Results are statistically analyzed. From the regression analysis, the drape coefficients of seamed heavy weight knit fabrics and the rating values obtained from a subjective analyses are predicted with 0.80 and 0.86 correlation coefficients, respectively.
Effect of Nozzle Geometry on Hydroentangling Water Jets: Experimental Observations
Authors: Begenir A. , Tafreshi H. Vahedi , Pourdeyhimi B.
Published: March 2008

This paper reports on the role of nozzle geometry on the characteristics of hydroen tangling water jets, specifically the behavior of three different conventional nozzle geometries under pressures below 3500 psi. Profiles of the water jets are digitized with a Nikon Dlx digital camera from which we extract the water-jet breakup lengths and spray angles under different operating conditions. Our preliminary data indicate that the cone-up nozzle produces water jets with considerably shorter intact lengths and slightly larger spray angles and a higher coefficient of discharge compared to the two other geometries considered. We attribute this distinct behavior to friction-induced and cavitation-induced turbulence inside the cone-up nozzles; a constricted water jet is formed by cone-down or cylindrical nozzles. Our results are in excellent agreement with previous experimental and computational data.
Numerical and Experimental Study on Reducing Yarn Hairiness with the JetRing and JetWind
Authors: Zeng Y.C. , Yu C.W.
Published: March 2008

JetRing and JetWind techniques, which use air-jet nozzles to reduce yarn hairiness, are the latest innovations in spinning and winding of staple yarns. The reduction of yarn hairiness is investigated in this paper both numerically and experimentally. A two-phase air/fiber flow model is developed to simulate the wrapping of a protruding surface hair in the nozzle. The effects of nozzle pressure and jet orifice angle on yarn hairiness are studied by both theoretical predictions and experiments. The results show the consistency of the numerical and experimental study.
A Mathematical Model for Numerical Simulation of Weft Insertion on an Air-Jet Weaving Machine
Authors: Celik Nihat , Babaarslan Osman , Bandara M.P.U.
Published: March 2008

In air-jet weft insertion, the weft yarn is moved by the frictional drag between the air stream and the yarn surface. This paper reports the computer simulation of this process in order to determine the motion of the yarn during weft insertion. Forces acting on the weft . depend on time as well as the varying position of the weft during insertion. The mathematical model of the system is implemented with a worksheet, and the results are shown using a graphics package. These theoretical results are compared with those experimentally obtained for the weft yarn. Weft positions in the reed channel in relation to machine timing in terms of shaft degrees are measured by the stroboscope of the machine for several picks, and the average value is taken for each position. Weft speed is calculated based on this measurement.
Gross Morphology and Absorption Capacity of Cell-Fibers from the Fibrous Vascular System of Loofah (Luffa cylindrica)
Authors: Bal Kheir Eddine , Bal Youcef , Lallam Abdelaziz
Published: March 2008

This paper investigates the liquid absorbency potential of the vegetal cell-fibers (CF) of Luffa cylindrica (LC) in relation to their microscopic morphology. Absorption after drainage and centrifugation, involving deionized water and saline solutions, is measured on both the raw fibers of the vegetal net and the cell-fibers previously extracted from ligneous fibrous strands (FS) with NaOH-anthraquinone alkali treatment. The microspongy structure of the raw Fs-luffa, observed in the vegetal material by scanning electron microscopy (SEM), is formed by multicellular fibers (from 250 to 500) bonded together with a large lumen (5 to 30 μm) and containing small punctuations along the fibers as interconnections. Liquid absorption results show that this original structure of these promising fibers should contribute to good absorption capacity: 18.4g/g and 22.6g/g are respectively obtained with for broken raw FS and CF-luffa fluff treated by 5 wt % NaOH. Their absorption capacity for liquid improves with an additional formaldehyde treatment.
Quantitative Fiber Mixture Analysis by Scanning Electron Microscopy
Authors: Wortmann F.-J. , Augustin P.
Published: March 2008

During the Nice 2000 meeting of the Technology and Standards Committee of the International Wool Textile Organization, the test method "Scanning Electron Microscopic Analysis of Speciality Fibres and Sheep's Wool and their Blends" was installed as full test method TM 58. The 95%-confidence range of the blend composition q was identified as a suitable measure of accuracy. Due to practical limitations, only limited data were and will be available on the variability of q when retesting samples. To gain detailed insight into this variability beyond the limits of foreseeable availability of experimental data, namely through round trials, a computer model has been developed to reflect the practice of blend analysis according to TM-58. Modeling practically relevant blends with some what extreme fiber components confirms that the accuracy of the blend analysis, calcu lated on the basis of the Wildman/Bray formula, is in fact very robust. The modeled coefficients of variation of q do not exceed 10% and are generally smaller than those found, for example, in the 1995 CCMI round trial. Allowing, within reasonable limits, a somewhat higher variability of the confidence range in practice, we can conclude that the results corroborate the statements of TM-58 with respect to the accuracy of the method ology.
Resistance to Compression Behavior of Alpaca and Wool
Authors: Liu Xin , Wang Lijing , Wang Xungai
Published: March 2008

This study compares the resistance to compression behavior of wool and alpaca fibers. It shows that alpaca fibers have a much lower resistance to compression than wool, and there is little correlation between the resistance to compression and the curvature for alpaca fibers. Yet for wool fibers, the correlation between resistance to compression and curvature is very strong and positive. The differences in fiber curvature and scale profiles of alpaca and wool, together with the test method for resistance to compression, may explain their different resistances to compression.
Relation Between Twist Amplitude and Breaking Strength of Solospun Yams
Authors: Longdi Cheng  , Peihua Fu  , Xiuye Yu
Published: March 2008

Different twist amplitudes in Solospun and ring spun yarns are analyzed. The relation between breaking strength of the two yarn types is studied using a set of structural models of the yarns and the mathematical relation between twist amplitude and breaking strength. Finally, experiments prove the theoretical results.
Approaches to Discriminate the Characteristic Generic Hand of Fabrics
Authors: Shyr Tien-Wei , Lin Jer-Yan , Lai Shin-Song
Published: March 2008

Discriminating between the hand of different fabrics is an important issue in the textile industry. This study focuses on the approaches to discriminate between fabrics with different characteristic generic hands. Four groups of woven fabrics from cotton, linen, wool, and silk are the fabric types in this study. Discriminant analysis and the neural network method are used to characterize and discriminate between the different fabric groups. The parameters for analysis are selected using a stepwise method from sixteen mechanical properties based on the KES-FB system. The results show that cotton, linen, wool, and silk groups of fabric can be characterized and discriminated by discriminant analysis and the neural network method with a 100% classification accuracy rate. There are fewer parameters with the neural network method than with the Fisher and canonical discriminant functions.
Circumferential Superdrawing of Hollow Poly(ethylene Terephthalate) Filaments
Authors: Aneja Arun Pal
Published: March 2008

Amorphous poly(ethylene terephthalate) (PET) can be stretched at low tension without causing any observable crystallization at temperatures above Tg. This resultant increased length with no measurable change in orientation is called superdrawing. Superdrawing of hollow PET fibers in the circumferential direction is demonstrated in a hot water bath accompanied by increased fiber void, which is caused by a combination of air expansion and water permeation. A three-parameter model defines the kinetics of the process. The phenomenon is characterized by a rapid rise in the fiber void with a subsequent steady state. The model parameters are obtained by a simple geometric technique. The initial fiber characteristics and morphology determine the rate of void increase and the final fiber geometry. Intrinsic fiber variability is reflected in the water permeability and energy of activation. The model predicts the total residence time required in the water bath to obtain maximum void size during the superdrawing process.
Neural Network Prediction of Human Psychological Perceptions of Fabric Hand
Authors: Hui C.L. , Lau T.W. , Ng S.F. , Chan K.C.C.
Published: March 2008

Fabric hand is commonly adopted for assessing fabric quality and prospective perfor mance in a particular end use. In general, fabric hand is primarily assessed subjectively. Subjective assessments treat fabric hand as a psychological reaction obtained from the sense of touch, based on the experience and sensitivity of humans. It is very difficult to predict such psychological perceptions of hand based on fabric properties. In this paper, we identify reliable sensory fabric hand attributes with correlated attributes of fabric properties, and we attempt a novel approach for predicting sensory hand based on fabric properties using a resilient back-propagation neural network. In this study, we assess forty woven fabrics to determine twelve significant fabric properties and fourteen reliable attributes of sensory hand. Our proposed system performs at a very low mean square error after fine tuning. Five extra woven fabrics are used to show that the performance of such a prediction system closely agrees with subjective test results. Our proposed system can allow field practitioners to evaluate their fabrics more closely to match with customers' expectations.
The Residual Electrostatic Voltage of Laminated Nonwovens with Different Surface Patterns
Authors: Lei C.H. , Lin J.H. , Chang C.H. , Lou C.W.
Published: March 2008

We have laminated polyamide nonwovens with different surface patterns and polypro pylene nonwovens of varying thicknesses and charge them in by a high voltage discharger. We then measure and analyze the remaining surface electrostatic voltage. Our results show that the patterns of nylon nonwovens can affect the residual electrostatic voltage, which increases with the thickness of the nonwovens. The increased surface area in the laminated nonwovens enhances their efficiency in dispersing electrons. These nonwovens can be used in general demands for anti-electrostatic usage.
Char Formation in Polyamides (Nylons 6 and 6.6) and Wool Keratin Phosphorylated by Polyol Phosphoryl Chlorides
Authors: Horrocks A. Richard , Sheng Zhang
Published: March 2008

Polyamides (nylon 6 and 6.6) phosphorylated by spirocyclic pentaerythritol phosphoryl chloride (SPDPC), cyclic 1,3-propanediol phosphoryl chloride (CPPC), and cyclic 2,2- diethyl-1,3-propanediol phosphoryl chloride (CDPPC) can yield phosphorus levels up to 0.7% (w/w). Calculations suggest that only primary amine groups at the end of the molecular chain are the possible phosphorylation sites. The presence of substituted 1,3-propanediol phosphonate moieties significantly increases polyamide char formation above 500°C, and scanning electron microscopy indicates that the residual char has an intumescent structure. SPDPC-phosphorylated wool keratin yields higher phosphorus levels up to 2.06%. For nylons 6 and 6.6, the presence of a methylolated triazine (as the commercial agent Lyofix MLF NEW, Ciba) in the pad-cured treatment can increase the phosphorus level further to significantly enhance char formation. SEM images suggest that the reacted substrates yield char volume expansions in wool of up to 336% compared to the control sample chars.
Anti-keratin Monoclonal Antibodies for Identifying Animal Hair Fibers
Authors: Paluzzi Silvio , Mormino Michele , Vineis Claudia , Tonin Claudio , Patrone Eligio , Barboro Paola , Balbi Cecilia
Published: March 2008

Type II keratins from cashmere are used as antigens to produce species-specific monoclonal antibodies for fiber identification purposes. Balb/c mice are immunized with the keratins purified by two-dimensional preparative gel electrophoresis. Hybridoma clones showing high immunological responses are subcloned by limiting dilution and then expanded to obtain antibodies in large amounts. When the antibodies are screened by two-dimensional immunoblotting for immunoreactivity with keratins isolated from cash mere and wool, several differences are detected, both quantitative and qualitative. Al though further work is needed to develop routine analytical protocols, the preliminary results reported in this paper appear to be extremely promising, and our approach could contribute to solving the problem of the objective identification of cashmere and other speciality animal fibers.
Modifying the UV Blocking Effect of Polyester Fabric
Authors: Gorenšek Marija , Sluga Franci
Published: March 2008

The influence of conventional acid and alkaline high temperature dyeing procedures on fabric construction is investigated. The effects of weave construction, orange, red, and blue disperse dyes, double layers of fabrics, and UV absorber on the ultraviolet protection factors (UPF) of polyester fabrics are the topics of this research. A spectrophotometer with an integrating sphere is used to measure the uv transmittance of polyester fabrics according to an AATCC test. Small differences in the weight of fabrics after blind dyeing procedures already influence the uv transmittance of fabrics. Pale orange and blue dyed fabrics show a high enough UPF, while a pale red dyed fabric does not reach such values. Deep dyed and double layered fabrics and fabrics aftertreated with a UV absorber reach high UPF values.
Mechanical Properties of Highly Elastic Complex Yarns with Spandex Made by a Novel Rotor Twister
Authors: Lin Jia-Horng , Chang Ching-Wen , Lou Ching-Wen , Hsing Wen-Hao
Published: March 2008

Elastic fibers are mostly used in elastic textiles. In this study, we develop a novel and original method to make highly elastic complex yarns using a self-designed, multi-section drawing frame and rotor twister. We examine the mechanical properties of these elastic complex yams. Their maximum breaking tenacity is high when the speed of the rotor is 4000 rpm and the wrapping count of the textured nylon filaments is either 2.5 or 3.0 turns/cm. These data are useful for the textile industry.