Showing papers in "Sen'i Kikai Gakkaishi (journal of The Textile Machinery Society of Japan) in 1986"

Relationship between Drapability and Mechanical Properties of Fabrics

Abstract: In order to evaluate formability of silhouette, drape coefficient obtained from circular specimen has been used.In this study, drape cofficient of lady's dress fabrics which are used mainly for one-piece dress or blouse is measured by FRL drape meter.And relationship between drapability and mechanical properties of fabrics is analyzed to correlate the drape coefficient with fabric mechanical property.Using mechanical parameters3√B/W, √2HB/W, 3√G/W and, √2HG/W which are derived from the analysis of bending of a cantilever of fabric having hystersis in bending and shear properties by applying the heavy elastica theory, the equation to described drape coefficient precisely is introduced.Where B, 2HB, W, G and 2 HG are bending rigidity, bending hysteresis, weight per unit area, shear stiffness and shear hysteresis respectively.As a result, it is shown that drape coefficient of lady's dress fabrics is very much influenced by√2HB/W and when the hysteresis in bending and shearing deformation of fabric is greater, the unstability in the drape shape becomes greater.Drape coefficient has high correlation with “HARI”and“SHINAYAKASA”and therefore, it is shown that drape coefficient is described also by primary hand values.

A Development in the Objective Measurement of the Quality ofKnitted Fabrics Used for Underwear

Abstract: The quality of the knitted fabrics used for underwear has been evaluated by means of hand judgement for along time by professional experts. In the series of this paper, the objective evaluation of this fabric quality isdeveloped by correlating the subjective quality judged by experts with some of measurable fabric characteristics.In the part 1, these fabric characteristics are selected and their measuring method are investigated. Thecharacteristics selected here are included in the two categories, fabric hand and the thermal/water transportproperty of the fabric.The fabric hands are those three primary hands expressed by hand values which are measured objectively, KOSHI (stiffness), NUMERI (smoothness) and FUKURAMI (fullness and bulkiness) for the quality on thecondition that these fabrics are used in winter season. On the summer season condition, SHARI (crispness) isapplied instead of NUMERI on the winter condition. These hand values are obtained objectively on the basicof fabric mechanical properties measured by KES-F system.Suitable measurement conditions of these mechanical parameters for the underwear fabrics are investigatedfirstly then the suitable equation translating these mechanical parameters into the primary hand values areselected from the translation equations which have been developed for the other type of fabrics.The thermal/water transport properties considered here are : qmax (a measure of warm/cool feeling), Qw (heat loss to air through fabric placed on a wet paper which simulates a wet skin), QD (the same measure as Qw but the fabric is placed on a dry heat plate), K' (heat conductance), MR (equilibrium regain) and WA (the maximum water content).These characteristic values of 80 comercial samples are measured and it is confirmed that these characteristicvalues well separate the fabrics of different quality.

Study on Interlaced Yarn

Abstract: The flow field in a yarn path is clarified by measuring pressure distributions at the surface of a yarn duct and flow velocity distributions near the surface of a yarn duct of an interlacer. An interlacer enlarged similarly to a real interlacer has been manufactured on the basis that the flow fields in two similar interlacers in geometry are also similar in dynamics. In this manner detailed measurements can be made and data with high accuracy can be obtained. Results are as follows.(1) With regard to the axial direction of the yarn duct, the pressure hs takes a maximum value in the neighborhood of Z=0 and a minimum in the neighborhood of |Z| =1, where Z is the axial distance from the center of the air jet nozzle non-dimensionalyzed by the diameter of the yarn path.The value of hs gradually increases with |Z|, and is identical with the atomospheric pressure at |Z| = 2. The above-mentioned tendency is independent of θ and p in the present experiment, where θ is the circumferential angle in the yarn duct from the center of the air jet nozzle and p is the air pressure in a rectification tank.(2) The variation of hs with respect to θ depends upon Z. In Z=0 the value of hs is extremely large at θ=180° and reaches a minimum in the vicinity of θ =90, 270°. In Z=1 it shows a considerably small variation, and a minus value in many regions. In Z=2 it is almost constant and nearly equal to the atomospheric pressure.(3) Comparing with p, the value of hs is almost equal to the atomospheric pressure in many parts of the surface of the yarn duct.(4) The air jetting from the air jet nozzle radially spreads after running against the wall opposite to the air jet nozzle. The air with a circumferential component of flow velocity flows along the curved wall, and two eddies which are symmetric with respect to the plane through θ =0 and 180° and rotate in opposite directions to each other are formed. With increasing |Z|, the circumferential component of flow velocity reduces and the axial component is dominant. The main flow moves from the periphery of the yarn path to its center.With regard to the circumferential direction of the yarn path, the flow is biased toward the semicircular region nearer to θ =180°.(5) The present experiment shows that the air flow pattern in a yarn path is independent of p.(6) It is considered, that the air jet causes opening and tangling actions of a yarn at the region (|Z|<1/2) where the jet directly runs against a yarn, and a yarn motion similar to a rotation at the region (|Z|<1) where the circumferential component of flow velocity is relatively dominant. (7) The influence of errors in manufacturing interlacers appears noticeably in the flow field in a yarn path.These errors are considered to cause various characteristics to yarns even when the processing conditions are the same in every interlacer.

Analysis of Tightening Tension Wave in Single-Needle Lockstitch Sewing Machine

Abstract: In sewing with a single-needle lockstitch sewing machine, the tightening tension wave in needle thread affects evidently the tightening situation of stiches. An attempt was made to clarify by the computer simulation, the basic mechanism of generation of the tightening tension wave.This stugy consists of two parts. This paper is the first of them. In the present paper, the method of computer simulation is proposed for the tightening tension wave at a very low sewing speed. The outline of this method is as follows : Simulation was done by using a simplified model for sewing mechanism. The calculation of tension in the model is based on the law of elasticity, where the calculation is classified into the following two cases depending on the effect of friction of thread take-up lever thread eyelet : 1) the thread take-up lever thread eyelet behaves as a fixed end at which the needle thread does not move due to the friction and 2) the needle thread moves being subjected to the friction.

Effects of Surface Active Agents and Builders on Fastness to Washing of Antibacterial Agents in the Latest Commercial Anticrobial Treatment Products

Abstract: This paper describes the effects of surface active agent and builder on the fastness to washing of antibacterial agents in commercial anticrobial treatment products.The results obtained are as follows. (1) With regard to the effects of detergents on the fastness to washing of antibacterial agents, the antibacterial activity to Staphylococcus aureus IFO 3060 with sample No. 1 was large in the order of : washing with water, light duty detergent, liquid detergent, soap powder, according to inclinations of each regression curves. Because the width of clear zone when washed with detergent having high concentration of surface active agents is smallas shown in the results of antibacterial activity test. negative correlation was recognized between the concentration of surface active agents in detergents and the inhibition percent. This tendency was similer to other three test organisms. (2) With regard to the effects of the kind of surface active agent on the fastness to washing of antibacterial agents, the antibacterial activity to three test organisms with sample No. 2 was small in the order of : marseies soap, soap, AOS, AES, LAS, control washing with water. Furthermore, the builder also influences the antibacterial activity, the degree of the effect on the antibacterial activity was lager sodium tripolyphosphate than sodium silicate. And the additive effects by combining the surface active agent with the builder were recognized .As the antibacterial activity of antibacterial agents in commercial anticrobial treatment products, therefore, is lost rapidly by washing with the detergents having high concentration of surface active agents, such as soap powder, it is necessary to use the detergents having low concentration of surface active agents and builders to keep the antibacterial and antifungal activities of antibacterial angents.

An Analysis of Dynamic Drape of Woven Fabric

Abstract: In order to investigate dynamic drape of woven fabric, vibrational property of weave was analysed theoretically and experimentally. The motion of weave was considered to be shear deformation and the shear vibrational property was analysed using differential equation. Vibration tester, which was modified KES-LABOMODEL shear tester, was used to examine the motion of the weave. It was shown that weave with buckling like sine wave (buckled-shaped weave) was considered to be equivalent to plate-shaped weave by some correction of weave characteristics such as shear stiffness and weave mass. Women's thin dress fabrics were examined their vibrational properties and their amplitude angles of vibration decreased linearly with time. This means that their shear vibration damp by frictional effect between fibres and/or between warp and weft yarns in the weave and that viscostic effect in the weave can be neglected in the range observed. Viscostic effect of air resistance is also neglected when the length of weave is small (smaller than 0.1 m), but it becomes distinct if the length is large (larger than 0.5 m).The amplitude damping angle is in proportion to 2HGo/Go which are characteristic values of weave shear property measured by KESF system.

Foam Dyeing of One Side of the Wool Blanket

Abstract: A study on the foam dyeing to wool blankets is reported with respect to the foam conditions to obtain the level dyeing without a skittery appearance and/or a sandwith effect. The foam application system is the lab-scale equipment bulit as a trial. It was possible that the dyeing solutions which contain the dyes and the foaming auxiliaries (a foamer, a stabiliser, a thickener, etc) could be suitably foamed and applied to the blanket on the foam application system. From the results on the dyed blankets using the foam of the different composition, it was found that the satisfactory level dyeing, as well as the dyeing using the coaservate system, was accomplished by the more viscouse, stable, uniform foams which are generated by adding the stabilizer and the thickener to the dyeing solution. Further, the effects of the other auxiliaries on the level dyeing were also discussed.

Wear Sensations of Wet Fabrics

Abstract: The wear sensations of wet fabrics have been examined by the wear trials. Four arm covers consisting of cotton, wool, polyester and acrylics fibers are used as specimens. The results are summarized asfollows : (1) This wear trials have been examined under three ambient conditions, i. e., 10°C/65% R.H., 20°C/65% R.H. and 30°C/65% R.H. The most significant difference of the wear sensations are found between the dry and the wet fabric at an amebient temperature of 20°C. The subjective estimation of coolness is obtained at an ambient temperature of10°C. The subjective estimation of the sence of touch and humidity is obtained at an ambient temperature of 30°C. (2) The features of various kinds of wet fabrics are found by this wear trials. It is found that a wet wool fabric is better than other textile fabrics in the subjective estimation of warmness and humidity.

Stiffness of Fabrics Made by Open End Yarns

Abstract: Open end yarns are structurally different in character from ring spun yarns. This difference in structure could affect the yarn properties and consequently the fabric properties. This paper attempts a comparison of the stiffness propeties of open end yarn fabrics and similar ring spun yarn fabrics using the SITRA Electronic Stiffness Tester. The important conclusions are that although open end fabrics show a higher stiffness than similar ring spun fabrics, there are directions in which the stiffness of open end fabrics is lower. Also comparison has been made of the stiffness behaviour of a open end fabric pile with that of the ring spun fabric pile.