bluuebunny/crossref_metadata_2025 huggingface dataset:
The Optics of the Wool Fiber Diameter Analyzer
Authors: Glass M. , Dabbs T.P. , Chudleigh P.W.
Published: March 2008

The optics underlying the operation of the wool fiber diameter analyzer ( FDA ) is explained in terms of the formation of a Fresnel diffraction shadow behind a strip mask. Consequently, the measurement technique is sensitive only to fiber diameter and is independent of internal properties such as color or refractive index. Using an approximate technique, the Huygens-Fresnel theory of diffraction is modified to account for a finite sized source with non-uniform illumination. This allows the FDA optics to be modeled using a new technique of modified Fresnel integrals. The method, which applies a one-dimensional approach to a two-dimensional problem, is computationally simple and gives an accurate description of optical phenomena encoun tered in the FDA. The model provides a powerful design and analysis tool for this class of instrument and has proved useful in elucidating potential sources of error.
A Computer-Aided Grading System for Both Basic Block and Adapted Clothing Patterns
Authors: Liu Z. , Harlock S.C.
Published: March 2008

Part I described the derivation of a grade rule data file. This paper explains algorithms that use the data file to automatically grade both basic block patterns and adapted patterns. A technique of "nearest point" is proposed whereby a new or displaced point on an adapted pattern derives its grade rules from the point on the basic block pattern closest to it. This technique facilitates, automatically, the grading process of both a basic block pattern and an adapted pattern. Some special treatments are considered to improve grading quality and meet special requirements.
A Developmental Study of Single Fiber Strength: Greenhouse Grown SJ-2 Acala Cotton
Authors: Hsieh Y.-L. , Honik E. , Hartzell M.M.
Published: March 2008

Single fiber strengths (breaking force in grams and breaking tenacity in g/tex) are reported for greenhouse grown SJ-2 Acala cotton fibers during growth and development. The developmental stages, which are defined by the age of the boll in the number of days post-anthesis (dpa) include primary wall formation, primary-to-secondary wall transition, secondary wall thickening, and maturity. A total of 54 bolls from 12 plants were used. Fiber properties were measured on the middle sections of fibers sampled from the middle section of the most developed ovules or seeds at the specific development stages. The most significant increases in single fiber breaking forces and fiber linear densities occurred up to 35 dpa and were correlated to seed fibers weighing up to 150 mg. Maximum breaking strength or tenacity of the SJ-2 cotton fibers is reached at 21 dpa. The absolute forces required to break individual fibers continue to increase with fiber development beyond 21 dpa without further increases in fiber tenacity. Dried seed fiber weight, fiber thickness, lengths between adjacent twists, and linear density (tex) have shown close relationships with the developmental stages and can serve as indicators for fiber development. Positional effects on single fiber strength were not revealed for bolls above the fourth fruiting branch.
Applying an Artificial Neural Network to Pattern Recognition in Fabric Defects
Authors: Tsai I-Shou , Lin Chung-Hua , Lin Jeng-Jong
Published: March 2008

In this paper, we evaluate the efficiency and accuracy of a method of detecting fabric defects that have been classified into different categories by a neural network. Four kinds of fabric defects most likely to be found during weaving were learned by the network. Based on the principle of the back-propagation algorithm of learning rule, fabric defects could be detected and classified exactly. The method used for processing image feature extraction is a co-occurrence-based method, by which six feature parameters are obtained. All of them consist of contrast measurements, which involve three spatial displacements (i.e., 1, 12, 16) and four directions (0, 45, 90, 135 degrees) of fabric defects' images used for classification. The results show that fabric defects inspected by means of image recognition in accordance with the artificial neural network agree approximately with initial expectations.
Multilamellar Liposomes Including Cholesterol as Carriers of Azobenzene Disperse Dyes in Wool Dyeing
Authors: De La Maza A. , Manich A.M. , Coderch L. , Parra J.L.
Published: March 2008

We have investigated multilamellar lipid vesicles (MLV) of defined size (400 nm) containing increasing amounts of cholesterol (CH ) as carriers of azobenzene disperse dyes to wool fibers. The liposomes are made from egg phosphatidylcholine (PC) and contain CI Disperse Orange 1 at different PC : CH relative concentrations. The physical stability of these systems is assessed by measuring the mean vesicle size distribution of the vesicle suspensions after preparation and during the dyeing process. Kinetic aspects involve dye adsorption and bonding on untreated wool samples by means of MLV liposomes at different PC : CH ratios. This process leads to the controlled ex haustion of dye in wool samples, which depends on the liposome lipid concentration. Increasing amounts of CH in bilayers result in a slight decrease in the dye exhaustion, although improving the total amounts of dye bonded to wool fibers. The optimum balance is reached for the maximum concentration of CH in bilayers, using the dye/ lipid weight ratio corresponding to the maximum encapsulation efficiency of the dye. This technological application also improves the dispersing efficiency of these systems with respect to the use of conventional dispersing agents.
Tensile Properties of Textured Polyester Woven Fabrics: Theoretical Model for Plain Weave Fabric
Authors: Salem Elsaid H. , Johnson Roy H. , Mohamed Mansour H.
Published: March 2008

A force-geometric model is developed to predict the stress-strain relationship of textured polyester woven fabrics for small strains. The model is based on yarn param eters, fabric geometry, and force equilibrium principles. Strains due to removal of weave crimp, removal of textured yarn crimp, and extension of textured yam filaments are assumed to be in series and then summed to yield total predicted fabric strain as a function of stress. Only two strain components are considered: strain due to weave crimp removal and to textured yarn crimp removal. The analysis adopted by Johnson is used to derive the weave crimp component. Predicted stress-strain curves are com pared to experimental curves for eight different fabrics representing two levels of feed yarns and four levels of textured yarns; the fabrics are in the dyed state, having been woven and hot water bulked prior to jet dyeing. In this state, these textured woven fabrics have maximum stretch potential resulting from yarn crimp in the woven fabric and textured filament crimp generated during wet finishing. There is good agreement between experimental and predicted stress-strain curves for low modulus fabrics, but agreement between predicted and experimental values is not good in all cases.
Introductory Study of Structures of Cotton Motes and Mote Fibers
Authors: Goynes W.R. , Ingber B.F. , Thibodeaux D.P.
Published: March 2008

Abnormalities in cotton fibers and seed formation produce materials that cause defects during production of textiles. The source of some of these defects has been traced to motes and mote, or undeveloped, fibers. Structures of motes and mote fibers are shown using light and electron microscopy. Bolls collected from normal. stressed, and diseased plants are compared for numbers and kinds of motes. Small motes are difficult to separate from fiber bundles after boll opening. Large motes have undevel oped embryos and break apart more readily than do normally developed seeds. Mote fibers may develop into long, hollow tubes without secondary cellulose layers. These flat fibers contain little cellulose compared to fully developed fibers. Both the chemical and physical structures of motes and mote fibers contribute to defects in textile products.
Near-IR Spectrophotometric Technique for Fast Identification of Carboxycellulose in Linen Fibers—A Preliminary Report
Authors: Kouznetsov Dmitri A. , Ivanov Andrey A.
Published: March 2008

Near-infrared ( NIR ) reflectance spectrophotometry has been successfully used for rapid, efficient identification of carboxylated cellulose in whole (nondisintegrated) linen textile samples subjected to a thermal treatment in the presence of high CO and CO2 concentrations. Mass spectrometric analysis of enzymatic hydrolysates of the treated textiles demonstrates the existence of carboxylated D-glucose residues produced by this procedure. Near-infrared spectrophotometry proves to be an accurate and simple approach to fast identification and characterization of these carboxylated cel lulose derivatives in whole textile samples.
Probability Failure Modeling of Woven Fiber Networks
Authors: Laumakis P.J. , Harlow D.G.
Published: March 2008

A probability model is developed to describe the failure of a biaxially loaded woven fiber network. The system under consideration consists of fibers arranged in a mutually orthogonal, simple weave pattern. The primary goal is to estimate the cumulative distribution function for failure of the network as a function of the fiber properties and the failure mechanism. The two-dimensional load sharing model is applicable to systems consisting of different fibers and various biaxial loading conditions. An al gorithm that explicitly computes the distribution function is developed and evaluated numerically. Results are qualitatively consistent with other lattice models.
Liquid Transport in Fabric Structures
Authors: Hsieh You-Lo
Published: March 2008

Liquid movement in any porous medium is driven by capillary action, which is governed by the liquid's properties, liquid-medium surface interaction, and geometric configurations of the pore structure in the medium. Pore structures of media, partic ularly fibrous materials, are complex and difficult to quantify. This paper discusses wetting and capillary theories and applications of these principles to the analysis of liquid wetting and transport in capillaries and fibrous materials. The derivations for external wetting contact angle and internal liquid transport are confirmed by micro balance measurements of glass capillaries and woven fabrics. The pore area responsible for liquid transport can be derived from mass transport data. This paper reports on the contribution of fiber surface properties and fabric pore structure to liquid transport and retention phenomena in 100% cotton and polyester fabrics.
Conductivity Measurement—A Simple Method for Determining Dye / Surfactant Interaction
Authors: Jocić Dragan
Published: March 2008

Surfactants present in the dyebath are responsible for a considerable change in the state of dye in solution, predominately caused by interactions between dye and sur factant. Among several known methods for investigating these interactions, the con ductivity measurement is a simple and accessible method for determining the degree of interaction between direct or acid dye and nonylphenolethoxylates. In order to explain the results conveniently, a fraction named the conductance ratio is defined and used as a measure of the degree of dye /surfactant interaction. The kind of surfactant does indeed exert significant influence on the degree of interaction.
An Integrated Approach to Dynamic Analysis of the Ring Spinning Process
Authors: Batra Subhash K. , Ghosh Tushar K. , Zeng Q. , Robert Kearny Q. , Fraser W. Barrie
Published: March 2008

This paper will show that the theory of ring spinning developed by Batra et al. and subsequently by Fraser can be used to explain recent experimental results obtained at the SRRC. In particular, Fraser showed that the quasi-stationary, nonlinear equations of motion relevant to ring spinning, including the effect of centripetal acceleration and air drag force, developed earlier by several investigators exhibit a bifurcation phe nomenon typical of many other nonlinear systems in mathematical physics. This investigation shows that the bifurcation analysis applied in a way that simulates for mation of the bobbin, even a chase of the bobbin, reveals meta-stability in parametric space, which can be used to explain the instabilities in free (no control rings) balloon profiles observed experimentally.
Biodeterioration of Nonwoven Fabrics
Authors: Goynes Wilton R. , Moreau Jerry P. , Delucca Anthony J. , Ingber Bruce F.
Published: March 2008

The use of nonwoven fabrics in disposable, convenience products generates high quantities of wastes that are not biodegradable. Synthetic fibers provide a major source of materials for these disposable products. Because synthetics are generally less bio degradable than natural fibers, it appears that for maximum degradability, natural fibers are a likely choice of materials for disposable goods. To compare rates of bio deterioration for natural and synthetic fibers, we examined changes in the structure and strength of nonwoven fabrics containing cotton and polypropylene, a synthetic fiber widely used in nonwovens, after controlled exposure of fabrics to fungi normally found in soil. Fungi grew extensively only on cotton fibers. Fungal growth rates were highest on 100% cotton and decreased to zero on 100% polypropylene. Significant losses in strength occurred only in samples with a high cotton content. Progression of cotton fiber deterioration was followed using the microscope until only polypropylene . fibers remained in the fabrics.
Yarn Strength Prediction Using Neural Networks
Authors: Luo Cheng  , Adams David L.
Published: March 2008

Over the past several years, numerous relationships between fiber properties and yarn performance have been developed. The classical method for predicting yam performance is statistical analysis such as linear multiple regression. Neural networks are now a subject of interest in many fields and a tool for many areas of problem solving. This study investigates the application of neural networks to yarn strength prediction. HVI test results of the 1989 crop are used to train the neural nets and performance is discussed.
X-Ray Photoelectron Spectroscopic Study of Wool Modified by Gaseous Fluorine
Authors: Kidd B. , Carr C.M. , Dodd K.J. , Vickerman J. , Byrne K.
Published: March 2008

X-ray photoelectron spectroscopy (XPS) is used to investigate the chemical mod ification of wool fibers arising from gaseous fluorination. Oxidation of the disulphide bond occurs together with a concomitant decrease in felt shrinkage.
Quality Measurement of Knitted Apparel Fabrics
Authors: Gong R.H.
Published: March 2008

The possibility is investigated of objectively measuring and controlling the quality of knitted garments during finishing. Results of an industry-based study on the quality and hand of knitted garments are reported. The association of the hand of knitted garments with KES-FB parameters is discussed, along with the requirements for an objective testing technique suitable for routine quality control in the finishing factory.
Influence of Waste Polymer Inclusion on the Performance of Oriented Polypropylene Geotextile Tapes
Authors: Horrocks A. Richard , Richards Andrew F. , Ghosh Subhas
Published: March 2008

Changes occurring in the tensile properties of oriented polypropylene tapes have been investigated following the addition of recycled process waste at various concen trations. In addition, the effects on resulting tape properties of adding stabilizers to blends of virgin polymer and waste prior to extrusion are determined. A significant loss in tape strength occurs when recycled or waste polypropylene is added because of thermooxidative degradation, as indicated by MFI and GPC studies. Our results demonstrate that useful tapes with acceptable tenacities in excess of 0.5 Ntex-1 can be achieved using up to 25% w/w of some recycled waste polymers in the absence of stabilizers. However, simultaneous introduction of a specified antioxidant system per mits waste polymer additions as high as 75% while maintaining acceptable tensile properties.
Crosslinking Cotton Fabric with DMDMDHEU Using Water /Methanol Mixtures as Solvents
Authors: Hsiung Han-Hsing , Chen Cheng-Chi
Published: March 2008

Cotton fabric is finished with dimethylodimethyldihydroxyethyleneurea using the pad-dry-cure process and different weight ratios of H2O/MeOH mixtures as solvents. Relationships between physical properties and weight ratios of H2O/MeOH show that WCRA and TSR values for the H2O/MeOH mixtures are higher than the theoretical values, but DCRA, nitrogen content, and formaldehyde content values for the H2O/ MeOH mixtures are lower than the theoretical values. WCRA values of the fabric samples treated using H20/MeOH = 40/60 mixtures are higher than those using the 100% water and methanol at the same DCRA and TSR values; in addition, WCRA values of the fabric samples treated using 100% methanol are higher than those using 100% water at the same DCRA and TSR values. The H2O/MeOH = 40/60 mixture gives higher WCRA values than the 100% methanol and water at the same CL/AGU, and the H 2O/MeOH = 0/100 gives higher WCRA values than the H2O/MeOH = 100/0 at the same CL/AGU. For a given CL/AGU, the TSR values of the treated fabric using the three different H2O/MeOH mixtures as solvents are ranked 0/100 > 40/60> 100 / 0, but DCRA values show an opposite trend. At the same CL /AGU, the CL lengths of the samples treated with mixtures of H2O/MeOH as solvents are ranked 0/100 > 40/60 > 100/0.
Structural Modeling of Double-Braided Synthetic Fiber Ropes
Authors: Wu Hwai-Chung , Seo Moon Hwo , Backer Stanley , Mandell John F.
Published: March 2008

This study is primarily concerned with the performance of double-braided ropes. widely used in marine applications. The mechanical properties of such ropes are ob tained by combining their structural features and the constitutive behavior of individual rope components. Emphasis in this study is on the tensile behavior of straight ropes as well as bent ropes, either an eye splice or in a continuous loop around a bollard- like pin. In the former case, precycling and water effects on the model predictions are discussed. For new small ropes, bending rigidity is negligible, so the bending effect is considered by modifying the geometry of the rope to allow for variation of helix periods and change of cross-sectional shapes from circular to elliptical ( flattened ) . For two extreme frictional conditions considered, i.e., infinite and zero friction, predictions of small nylon rope behavior agree well with experimental results for both simple tension and tension plus bending. There is less agreement for small PET ropes, par , ticularly in bending tests.
An Algorithm for Optimizing Color Prediction in Blends
Authors: Amirshahi S.H. , Pailthorpe M.T.
Published: March 2008

Some suggestions are presented in this paper for optimizing color matching in blends of pre-colored fibers. The proposed algorithm suggests an initial spectrophotometric trial for color matching with all selected colored fibers. If the initial spectrophotometric match does not satisfy the colorimetric conditions, the data will be applied in a later colorimetric attempt. In that attempt, by applying the pseudoinverse algorithm in the iterative process, it is not necessary to limit the number of colored fibers to four, as Allen suggested for the two-constant theory.
Influence of Opening Force During OE Spinning on Fiber Geometry
Authors: Nikoli Momir , Bukošek Vili
Published: March 2008

This paper deals with the dynamics of sliver separation into flocks, little flocks, and individual fibers during the OE spinning process. A functional dependence is deter mined for the opening force exerted on a clamped sliver tuft. The influence of the opening force on fiber geometry simulated with a double helix model is established. Fiber coiling is simulated with a primary helix and fiber crimping with a secondary helix. The decoiling and decrimping forces and the degrees of fiber extendedness as a function of the tensile force during gradual loading are measured for cotton, regenerated cellulose-viscose, and cotton-type PAN and PES fibers. The function of the opening roller rotation speed and the degrees of fiber extendedness during the OE spinning process are established.
Electrokinetic Properties of Modified Polyester Fibers
Authors: Teli M.D. , Rao B.R.
Published: March 2008

Electrokinetic properties of easily dyed cationic dyeable polyester (ED-CDPET) fibers of different deniers and cationic dyeable polyester (CDPET) fibers containing varying numbers of sulfonic groups are examined when cationic dye solutions are streamed through their plugs. There is a decrease in the negative zeta potential with more sulfonic groups in the chemical composition of fibers. This may be attributed to enhanced adsorption of dye cations by the increased number of polar sulfonic groups on the fibers. Of the two fibers, ED-CDPET exhibits lower negative zeta potential compared to CDPET with identical sulfonic group content, which may be attributed to the im proved accessibility of the sulfonic groups to the dye cations. Maximum denier ED- CDPET shows the least negative zeta potential of the samples of various deniers studied. Heat setting (at 180°C, 90 seconds) lowers the negative zeta potential, which may be due to decreased surface area. Results in surface charge density and surface conductivity are also discussed.
Effects of Fiber Opening on the Uniformity of Rotor Spun Yarns
Authors: Kong L.X. , Platfoot R.A. , Wang X.
Published: March 2008

We have studied the dependency of rotor spun yam uniformity on variations of rotor speed, opening roller speed, and twist level. The number of points per fiber (ppf), which reflects the level of fiber opening, is useful in evaluating the effects of spinning parameters on yarn uniformity. Experiments based on a 60 tex yam indicate that the properties of yarn unevenness and incidence of imperfections improve as ppf increases due to improved fiber separation. A critical value of the ppf is identified for CV% values and other measures of imperfections. Beyond this critical value, further increases in the ppf do not lead to any significant improvement in those yam properties. This is due to the high level of fiber breakage at high ppf values.
Sorption of Azo Disperse Dyes by Nylon 6 from Water
Authors: Shibusawa Takao
Published: March 2008

Sorption isotherms of purified azo disperse dyes and their model compounds on nylon 6 from water are measured in a temperature range of 40-90°C. Most isotherms are curved, convex upward, in the range of low dye concentration in water. Analysis of the isotherms using Freundlich sorption and a dual-mode sorption model shows that the isotherms follow the latter, in which Nemst-type partitioning and simple Langmuir sorption are concurrently operative. The amount of dye ( CL) on the polymer sorbed by Langmuir sorption is usually much smaller than that ( Cp) by partitioning. Dyes with the hydrogen atom capable of forming an intermolecular hydrogen bond show high substantivity for nylon 6. The hydrogen bond between nylon 6 and the hydrogen atom of the amino group or the 4- N-substituted-(2-hydroxyethyl) group in the dye seems to be involved in Langmuir sorption. For dyes with 4-amino and two 4- N-substituted-(2-hydroxyethyl) groups, the number of Langmuir sorption sites ( S) decreases gradually with increasing temperature, while for dyes with only one 4- N- substituted-(2-hydroxyethyl ) group, S decreases abruptly with increasing temperature. In some cases, the Langmuir sorption mode seems to diminish at a high temperature: the sorption isotherms become almost linear.
Low Stress Mechanical Behavior of Cotton / Polyester Yarns and Fabrics in Relation to Fiber Distribution Within the Yarn
Authors: Radhakrishnaiah P. , Sawhney A.P.S.
Published: March 2008

Low stress mechanical properties of cotton /polyester yams representing random fiber disposition and core-sheath construction are compared to determine the influence of fiber distribution on yam properties. The yams are converted into plain weave fabrics under identical conditions, and fabric properties are compared to understand how yam properties translate into fabric properties. The core-sheath yarn (polyester core/cotton-covered yam) shows lower values for bending rigidity, bending hysteresis, compressive resilience, and tensile elongation. The same yarn also shows higher values for compressive softness and tensile modulus. The lower tensile elongation and higher tensile modulus of the core-sheath yam is reflected in the lower elongation and higher modulus of the corresponding fabric. However, bending and compression properties of the core-sheath yarn are inversely related to bending and compression properties of the corresponding fabric. Results show that yarn bulk and compression properties exert a greater influence on the bending behavior of a plain weave fabric than yarn bending properties. Results also reveal that a closely woven plain weave fabric made from a less resilient and easily compressible yarn can prove to be more resilient to compression and more difficult to compress in the fabric stage.
A Laboratory Model for Studying Environmently Dependent Chemical Modifications in Textile Cellulose
Authors: Kouznetsov Dmitri A. , Ivanov Andrey A. , Veletsky Pavel R. , Charsky Vyacheslav L. , Beklemishev Oleg S.
Published: March 2008

We have developed a laboratory model to evaluate possible microbial impact on cellulose during long-term contact with air microorganisms. This model is based on the capillary zone electrophoretic /mass spectrometric estimation of modified glucose residues in cellulose enzymatic hydrolysates isolated from linen samples. We subjected these samples to a pump-directed air flow line for 8 days and 10 weeks. Simultaneously, we measured protein contamination of the samples followed by AMS-determination of the associated 14C and 13C values. All measurements were done in non-aseptic environments in two different geographical/ecological regions. We pre-impregnated all experimental samples with deionized water and pretreated the control samples with urea and sodium azide in order to prevent both enzymatic activity and microbial growth. Our results show that the filtration of atmospheric air through the linen samples leads to a statistically significant methylation and acetylation of textile cellulose, de pending on air volume (and therefore the amount of air bacteria cells), ecological conditions, and the presence of bacteriostatic (sodium azide) and protein denaturing ( urea ) agents. We found that the amount of alkylation in the cellulose samples correlates with the measured 14C and 13C values and protein contamination levels. A biochemical mechanism of the phenomenon and its possible application for forensic and archae ological chemistry are under discussion.
Influence of Oxidation Conditions on Polyacrylonitrile-Based, Activated Hollow Carbon Fibers
Authors: Yang Ming-Chien , Yu Da-Guang
Published: March 2008

Polyacrylonitrile hollow fibers are oxidized at three different temperatures and var ious durations, and then further carbonized in nitrogen and activated with carbon dioxide. The influence of oxidation conditions on the properties of the resulting ac tivated hollow carbon fibers is discussed. Activated hollow carbon fibers at the highest oxidation temperature have the lowest mechanical properties, and stick together on the surface due to quick heating during oxidation. The higher the oxidation temper ature, the larger the size of the pores, and the pores are almost always concentrated at the center of the wall of the hollow fiber. However, activated hollow carbon fibers at the lowest oxidation temperature have higher mechanical properties, fewer pores of large size, and larger surface areas, which exhibit greater hysteresis effects in nitrogen adsorbing at low pressure.
A Spinning Concept for Producing Woolen Carpet Yarns Directly from Card Sliver
Authors: Lawrence C.A. , Chiu S.F.
Published: March 2008

A new ring spinning concept is described, termed "disc-ring spinning," which enables woolen yams to be produced directly from a carded sliver feed. Experiments are un dertaken on a single spindle machine in order to elucidate the importance of the various design variables of the spinning system to the stability of the process and the properties of 100% wool yams. High speed photography is used to study the changes in the configuration of fibers during the spinning process, which will determine the structural characteristics of a woolen yam. The results of the work show that disc-ring spinning offers the opportunity for carpet yam manufacturers to dispense with a con denser at the woolen card, with the benefit of a more cost-effective production process.
Effect of Mutual Bonding of Textile Layers on Thermal Insulation and Thermal Contact Properties of Fabric Assemblies
Authors: Hes Lubos , De Araujo Mario , Djulay Valentin V.
Published: March 2008

This paper deals with thermal insulation and thermal contact properties of woven fabric assemblies used to produce men's jackets. An important part of the paper is the description of the new computer-controlled instrument, the Alambeta, to measure insulation and thermal contact properties of fabrics. The heat flow passing between the textile sample and measuring head during thermal contact is measured directly by a special thin sensor, whose thermal inertia is similar to that of human skin. Thus, the instrument's warm-cool feeling sensitivity aproximates human skin. Spotbonding the outer fabric interlining and lining together reduces the total thermal resistance of the assembly and simultaneously increases (makes cooler) thermal absorptivity, a new parameter used to describe the warm-cool feeling of fabric. The meaning of this pa rameter, which mainly reflects the surface properties of the fabrics and whose level does not depend on experimental conditions, is explained in detail. The effect of temperature drop on the thermal properties of the fabric assemblies is also investigated. The increased resulting thermal conductivity with the average temperature of the assembly is a consequence of the increased portion of the heat transferred through the system by radiation.
Developments in Automatic Control of Sewing Parameters
Authors: Rocha A.M. , Lima M.F. , Ferreira F.N. , Araújo M.D.
Published: March 2008

Advanced sewing machines should be able to set up automatically, detect sewing faults, and self-adjust to required settings. In order to achieve this objective, a sewing machine has been instrumented with sensors, so that wave forms of needle penetration and withdrawal forces, presser-foot compression force, and sewing thread tensions can be captured and analyzed. This study makes it possible to understand the dynamics of sewing at the various interfaces—sewing thread / fabric, sewing thread / sewing ma chine, fabric/sewing machine—and to develop a computer program and adequate hardware to control the sewing operation through an "on-line adaptive control system." In addition, the equipment can also be used to develop sewing specifications, for quick set up, and to test sewability.
Description and Application of an Acoustic Pulse Detector to Nylon 6 and Polypropylene Single Fiber Fracture
Authors: Ellison Michael S. , Jindrong Dai
Published: March 2008

We have developed a microcomputer-based instrument for detecting and analyzing the acoustic frequency pulse generated upon fracture of single filaments. The current generation of instruments can determine the pulse height and width; work is underway on the next generation of equipment, which will allow further analysis of the acoustic signal and testing of a bundle of fibers. The nylon 6 (PA6) and polypropylene (PP) fibers, produced in-house with selected draw ratios and denier, are broken using stan dard tensile testing techniques; hence, the filament tensile properties of the specimens are easily compared with the characteristics of the associated acoustic pulse. The general shape of the acoustic pulse energy data distribution is skewed, such as that of a Poisson distribution; hence, we have calculated the median of the data for use in our analyses. Increasing the test gauge length increases the width of the acoustic pulse. We have found that fiber linear density has no significant direct effect on the acoustic pulse parameters. The acoustic pulse energy density (energy/unit area) correlates closely with the tensile work-to break of the fibers. There is a steeper slope to this relationship for the PP than for the PA6 fibers. From these observations, we can conclude that analyzing the acoustic pulse generated by breaking fibers provides information about the test length and, for fibers of the same polymer type, the average tensile rupture energy.
Effects of Cotton Fiber Blending and Processing on HVI Measurements—Part II
Authors: Fryer L.F. , Rust Jon P.
Published: March 2008

A review of literature about the effects of fiber property distributions and jaw place ment on HVI testing results is followed by a description of and results from an HVI computer simulator. A novel analysis of previously published data shows that mean and standard deviation of breaking load and elongation of a prepared test specimen vary with distance from the specimen clamp. Results of an HVI simulator based on theoretical considerations described here agree with experimental results. Placing jaws at different percent span lengths may introduce error into strength measurements by including a different subset of fibers with different fiber properties in each test. In addition, the MCI HVI air orifice used in strength tests may preferentially remove fiber crimp according to fiber elongation, which would result in an apparent increase in bundle strength.
Analysis of Air Flow in Single Nozzle Air-Jet Filling Insertion: Corrugated Channel Model
Authors: Adanur Sabit , Bakhtiyarov Sayavur
Published: March 2008

Air flow in air jet weaving machines is complicated: it is unsteady, turbulent, and can be compressible or incompressible depending on the velocity. A separated flow model is developed to simulate air flow through the guide channel, which is half open and corrugated. Subsonic air flow in the guide channel is investigated as a simplified model of air flow in a single nozzle air-jet filling insertion system. The drag coefficient in the guide channel and propelling force acting on the yarn are calculated. Theoretical predictions of drag coefficient and propelling force are in good agreement with ex perimental data obtained for the same conditions.
Analysis of Microfibril Orientation in Cotton Fibers by Fluorescence Polarization
Authors: Onogi Yoshihiko , Kamata Masayo , Nakao Tokie
Published: March 2008

Microfibril orientation in a cotton fiber surface is measured by the fluorescence polarization method using microphotometry. To serve as a cotton model, drawn nylon fibers are dyed with a high concentration of fluorescent probe and subjected to a twist tester to obtain certain twisting angles, which are then quantitatively determined from the angular distribution of the polarized fluorescence intensity. For naturally dried cotton fibers, this fluorescence polarization analysis shows the twisting angle to be 24.5°. The method also permits analysis of the twisting sense of fibrils in the surface of cotton fibers without needing to untwist them.
Diffusion of Disperse Dyes on Nylon 6
Authors: Shibusawa Takao
Published: March 2008

The diffusion behavior of nine azo and two anthraquinone dyes on nylon 6 film is studied by analyzing dye distribution profiles. Relations between concentrations Cf of dyes on the film and the actual diffusivities D( C) of the dyes ( Cf - D ( C) relation) are determined from the profiles using Matano's method. For most dyes, Cf - D( C) relations at 80-90°C are explained well in terms of the dual-mode sorption-diffusion model in which the dye penetrates the polymer as two distinct species: dye taken up by Nernst- type partitioning (P species) and by Langmuir sorption with one class of sorption site (L species). The actual diffusivity DP( C ) of the P species decreases gradually with de creasing Cf, from Cf at the polymer surface ( Cfsur) to Cf corresponding two to three times the saturation value of Langmuir sorption ( S). Below this Cf, D( C ) P decreases rapidly with decreasing Cf. Actual diffusivity DL(C) of the L species usually increases gradually with decreasing Cf. As a result, D ( C) values of disperse dyes are almost constant or gradually increase (or decrease) with decreasing Cf, from Cfsur to Cf corresponding to two to three times S, and then decrease rapidly with decreasing Cf. For diffusion of some dyes at low temperatures (<60°C), the C f - D( C) relations may be explained much more accurately by considering that all three sorption modes operate concur rently, i.e., Nernst-type partitioning and two classes of Langmuir sorption, one with high affinity and small S, and other with low affinity and large S.
Effects of Filament Modulus and Linear Density on the Properties of Air-Jet Textured Yarns
Authors: Sengupta A.K. , Kothari V.K. , Sensarma J.K.
Published: March 2008

The effect of filament initial modulus on textured yarn properties is studied, keeping other parameters constant. Initial modulus has a major influence on textured yarn properties. An increased initial modulus causes poor texturizability and therefore in ferior textured yarn properties such as poor bulk, stability, loop frequency, and higher nep level. A study of the effect of filament linear density on textured yarn properties shows that finer filaments produce better quality yarns as far as loop frequency, bulk, and instability values are concerned, but they also produce higher numbers of neps in the textured yarn.
Graft Polymerization onto Wool Pretreated with a Mercaptosilane
Authors: Kamshi Youichi , Arai Kozo
Published: March 2008

Wool fibers and fabrics pretreated with an isopropyl alcohol solution of 3-mercap topropyl trimthoxysilane containing various amounts of water have been grafted with 2-hydroxyethyl methacrylate in an aqueous solution of potassium peroxidisulfate. The Si atoms are evenly distributed in the radial direction of the pretreated fibers with higher water content. But for the fibers pretreated with isopropyl alcohol without water, the Si atoms are localized on the surface of the fibers. The elastic modulus in compression increases in the order: untreated wool < pretreated wool < grafted wool.
Formation of Cyclic Anhydride Intermediates and Esterification of Cotton Cellulose by Multifunctional Carboxylic Acids: An Infrared Spectroscopy Study
Authors: Yang Charles Q. , Xilie Wang
Published: March 2008

Multifunctional polycarboxylic acids have been used as nonformaldehyde cross linking agents for cotton fabrics to replace the traditional N-methylol reagents. Ester ification of cotton cellulose by seventeen aliphatic and aromatic polycarboxylic acids is studied using Fourier transform infrared spectroscopy. Five-membered cyclic an hydride intermediates formed under the curing conditions are identified on cotton fabrics treated with these acids. Only those polycarboxylic acids that form cyclic an hydride intermediates esterify cotton cellulose. Formation of the cyclic anhydride intermediates and esterification of cotton cellulose take place in the same curing tem perature regions. The infrared spectroscopy data also indicate that the second carboxyl group in a bifunctional carboxylic acid is not able to esterify cotton cellulose effectively. Therefore, we can conclude that a polycarboxylic acid esterifies cotton cellulose through the formation of a cyclic anhydride intermediate. The infrared spectroscopy data also reveal that 1,2,3,4-butanetetracarboxylic acid is the most effective crosslinking agent for cotton cellulose among the acids studied.
Comparison of Mechanical Properties of Shirting Materials Measured on the KES-F and FAST Instruments
Authors: Yick Kit-Lun , Cheng K.P.S. , Dhingra R.C. , How Y.L.
Published: March 2008

This study compares the test results of the FAST system (fabric assurance by simple testing) with those of the KES-F (Kawabata evaluation system for fabrics) for two series of twenty-two shirting materials in terms of their low-stress fabric mechanical properties of bending, shear, and tensile deformation. The first series of eighteen shirting fabrics, ranging in weight from 96 to 170 g/m2, was sampled from a leading Hong Kong shirt manufacturer. The second series of four denim shirting fabrics, ranging in weight from 199 to 217 g/m 2, was later included to test the validity of extrapolating the relationships observed for the first series of eighteen shirting materials. Despite some considerable differences in the measurement principles of the two testing systems, there are highly significant correlations between the parameters obtained from the test results of the two systems.
Wetting and Wicking
Authors: Kissa Erik
Published: March 2008

The fundamentals of wetting and wicking are reviewed. Wetting is the displacement of a fiber-air interface with a fiber-liquid interface. Wicking is the spontaneous flow of a liquid in a porous substrate, driven by capillary forces. Because capillary forces are caused by wetting, wicking is a result of spontaneous wetting in a capillary system. Fiber wettability is therefore a prerequisite for the occurrence of wicking. The inter action of liquids with textile fabrics may involve one or several physical phenomena. On basis of the relative amount of liquid involved and the mode of the liquid-fabric contact, the wicking processes can be divided into two groups: wicking from an infinite liquid reservoir (immersion, transplanar wicking, and longitudinal wicking), and wicking from a finite (limited) liquid reservoir (a single drop wicking into a fabric). According to fiber-liquid interactions, each of the four wicking processes can be divided into four categories: capillary penetration only, simultaneous capillary penetration and imbibition by the fibers (diffusion of the liquid into the interior of the fibers), capillary penetration and adsorption of a surfactant on fibers, and simultaneous cap illary penetration, imbibition by the fibers, and adsorption of a surfactant on fibers. When designing tests to simulate liquid-textile interactions of a practical process, it is essential to understand the primary processes involved and their kinetics.
Fatigue Behavior of Aramid Nonwoven Fabrics Under Hot-Press Conditions
Authors: Watanabe Akira , Miwa Minoru , Takeno Yoshiaki , Yokoi Teruyuki , Nakayama Akira
Published: March 2008

To develop heat-resistant nonwoven fabrics, nonwovens were subjected to repeated hot-press fatigue, and the mechanical properties of and configurational changes in the fabrics were examined. The mechanical properties of nonwovens depend on raw ma terials, fiber fineness, fiber length, needle punching density (numbers), fiber arrange ment, and structural differences resulting from differences in manufacturing. This paper reports on geometric structural influences on the mechanical properties of non woven fabrics after hot-press fatigue. We prepared two kinds of nonwovens using either the paper-making method or a needle punching machine, and one kind of woven fabric made on a four-ply weaving machine, and we investigated the influences of the fabrics' geometric structures on their compressive behavior. We expected that four-ply woven fabric would show better compressive behavior than the other non woven fabrics because it contains a lot of air. Our investigation showed, however, that the four-ply woven fabric behavior was very similar to that of the paper-like nonwoven fabric, while the needle-punched nonwoven behaved very differently from the others. In particular, we found that the needle-punched nonwoven fabric had good fatigue resistance and recovery properties, as shown by its small increase in compressive mod ulus and small change in compressive strain with fatigue cycles.
Effects of Molecular Weight on Melt Spinning and Mechanical Properties of High-Performance Poly(ethylene Terephthalate) Fibers
Authors: Ziabicki Andrzej
Published: March 2008

Effects of the molecular weight (intrinsic viscosity) of poly(ethylene terephthalate) on the formation of fibers and their properties are analyzed. Correlations between molecular weight and various viscosity characteristics are compared. Because of high melt viscosity, effective melt spinning is limited to polymers with intrinsic viscosities [η] not higher than 0.8-0.9 dl/g. High molecular weight polymers ([η] = 2.0-4.9 dl/ g) have been used for solution (gel) spinning. Molecular weight is not a primary characteristic responsible for mechanical properties, but it may affect tenacity and modulus indirectly. The tenacity of industrial PET fibers manufactured by a variety of processes exhibits positive correlation with intrinsic viscosity; the correlation of the modulus is less evident. Melt spun and drawn fibers exhibit tenacities of up to 12 g/ den and moduli of up to 220 g/den, while fibers solution spun from high molecular weight PET ([η] = 2.6 dl/g) subjected to deep drawing (total draw ratio = 16.4) reach a tenacity of 18.5 g/den and a modulus of 313.2 g/den. A new zone drawing and annealing process, apparently insensitive to molecular weight, yields PET fibers with a tenacity of 14 g/den and a modulus of 246 g/den. The role of molecular weight in obtaining high mechanical performance is discussed.
Modeling Mechanical Behavior of Fabric and Warp Yarn During Loom Stops
Authors: Vangheluwe Lieven , Kiekens Paul
Published: March 2008

This paper proposes a model for calculating relaxation behavior after dynamic load ing of fabric and of warp yarns. The model is based on fitting the parameters of an extended nonlinear Maxwell model to experimental data using nonlinear regression. Combining the models for fabric and warp yarns can yield the viscoelastic behavior of the fabric-yarn combination, as well as the cloth fell displacement during the re laxation period.
Heat Treatment of Cotton: Effect on Endotoxin Content, Fiber and Yarn Properties, and Processability
Authors: Rousselle Marie-Alice , Price John B. , Thomasson J.A. , Chun David T.W.
Published: March 2008

A specially designed device is used to heat several hundred pounds of cotton at temperatures previously shown to reduce endotoxin content during small-scale treat ment of cotton lint. Dust from heated and unheated (control) cotton is captured during processing in a pilot plant textile mill. The endotoxin content of fibers, bulk dust, and fine dust is reduced by the heating, compared to the unheated bale. The effect of heat treatment on fiber physical properties and processability is monitored to provide an assessment of the effect of heating on the market value of the cotton. Results from dust from heated fibers distributed to other researchers for in vivo and in vitro evaluation of physiological activity are discussed.
Measuring Fiber Orientation in Nonwovens
Authors: Pourdeyhimi B. , Ramanathan R. , Dent R.
Published: March 2008

, This paper addresses the development of an image analysis technique for direct tracking of fibers in an assembly. The algorithms are evaluated using simulated images presented in an earlier part of the series. The tracking method appears to be extremely efficient in determining fiber orientation distribution in nonwovens regardless of their structural characteristics.
Moisture Sorption and Transport in Clothing During Wear
Authors: Barnes J.C. , Holcombe B.V.
Published: March 2008

Discomfort results when sweat accumulates on the skin. The sorption of water vapor by hygroscopic clothing near the skin and its release when the clothing moves away from the body can enhance sweat removal. Such a process depends on the relative humidity being higher near the skin than in the ambient atmosphere, and may accompany heavy sweating. Experiments and theoretical models have indicated that a small effect of this kind may occur in wear.