The stability and recovery of rib fabrics produced from bulked nylon yarns

Jhangiani, Sunder Bulchand (1966) The stability and recovery of rib fabrics produced from bulked nylon yarns. PhD thesis, University of Glasgow.

Abstract

With the introduction of bulked synthetic yarns, investigations into the disensional properties of plain fabrics knitted from those yarns have been made and a certain amount of information obtained. In the present work an attempt has been made to extend that investigation to the 1 x 1 rib structure, which in addition to being of considerable commercial importance, is also the basic knitted ribbed structure. For fabrics knitted from bulked yarns, it is not sufficient that they should be only dimensionally stable but that they should process also the properties of case of extensibility and subsequent recovery from that extension. Therefore, the work was designed so as to cover the broad aspect of the properties and performance of rib fabrics. The first part of this thesis is concerned with the dimensional properties of 1 x 1 rib fabrics, whereas the second part deals with the load-strain and clastic recovery charactaristics of those fabrics. All the fabrics used in this work were knitted on a Universal Power Plat Machine without employing any positive feeding device. The influence of various yarn and machine variables such as yarn denier, crisp rigidity, filament denier, method of yarn bulking and alteration of stitch can setting on the dimensional and elastic recovery properties of 1 x 1 rib fabrics have been investigated. The work is concerned with the properties of fabrics knitted from bulked nylon yarns which were processed by false twist crimping and stuffer box bulking methods. The influence of three relaxation processes, steam relaxation, wet relaxation and city tumbling, upon the dimensional stability of fabrics has been investigated. A detailed assement has been made of the various methods of measuring yarn collapsing properties of the bulked yarne used in this work. Explanations have been given for different results obtained when the measurement were made in air after the yarns were given relaxation treatment and those obtained when the measurement were made in water by the standard H.A.T.R.A. crimp rigidity test. The yarn collapsing results have been compared with the performance of those yarns when knitted into fabrics. It has been found that a number of methods used in this work for measuring yarn collapsing properties predict reasonably well the behaviour of yarns comprised of lower denier filaments when in fabric form, but none of these methods appear suitable to predict the performance of yarns composed of higher denier filaments when knitted into fabrics. For such yarns, therefore, a method is required to measure their collapsing properties which would correlate with the actual collapse of these yarns in fabric form. From the geometry of plain knitted fabrics it is known that the length of yarn in a loop and the number of loops per unit area in the fabric are the predominant factors which affect the dimension of a fully relaxed fabric. The effect of yarn and knitting variables on the loop length and stitch density of 1x1 rib fabrics is discussed in the first part of this thesis, which also deals with other fabric properties such as fabric length to width ratio, area shrinkage, thickness, fabric bulk and fabric air permeability measurements. The limited use of the air permeability test as a measure of fabric bulk is shown. In order to calculate the relationship between relaxed and measured stitch length for 1x1 rib fabric, the same method has been used as that for plain knitted fabric and it is observed that the theory developed for the latter fabric is also generally applicable to 1x1 rib fabric. From the measurement of various fabric properties, it has been found that dry tumbling causes maximum collapse of the fabric and that steam relaxation is an ineffective process in this respect.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: A W Marvin
• Keywords: Textile research
• Date of Award: 1966
• Depositing User: Enlighten Team
• Unique ID: glathesis:1966-72253
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 24 May 2019 15:12
• Last Modified: 24 May 2019 15:12
• URI: https://theses.gla.ac.uk/id/eprint/72253