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YARN PROPERTIES
Twist: spiral turns given to the yarn to bind
individual fibres
Spun Fibres: short length fibres measured
in inches
Filament fibres: continuous length fibres
measured in meters.
YARN
A generic term for a continuous strand
of interlocked textile fibers or
filaments, in a form suitable for
knitting, weaving, or braiding
Yarn may or may not contain twist
YARN MADE FROM STAPLE FIBRES ALWAYS CONTAINS TWIST
YARN MADE FROM FILAMENT FIBRES MAY OR MAY NOT CONTAINS TWIST
Basis of difference
Filament yarn Spun yarn
Fibre length Short Continuous
Yarn Uniformity
Filament yarns are more uniform.
Less Uniformity
Yarn Smoothness and Luster
Smoother and lustrousExample: satin
Less smooth and somewhat dullerExample: Broadcloth
Yarn Strength
Stronger Weak Strength due to staple fiber.
Yarn Twist Low twist High TPI
FILAMENT AND SPUN YARNS
DIFFERENCE BETWEEN YARN AND THREAD
The main differences are:
Thread is used for sewing Yarn is used to construct fabrics (woven or
knitted)
A yarn is processed further to make a thread. A thread is usually a ply yarn, it is finer, more
even and stronger.
Thread
Yarn
Thread is always plied and twisted. These are mainly made up of cotton, nylon, polyester, rayon.
Thread is a tightly twisted strand
of two or more plys of yarn
Yarn may be single or plied, twisted or untwisted.
Left-twist thread is always used in
the sewing machine because the
action of the stitch-forming
mechanism tends to ravel or break
right-twist thread.
YARN TWIST
Twist is defined as the spiral arrangement of the fibres around the axis of the yarn.
Twist is produced by revolving the one end of a fibre strand while the other end held stationary.
Twist binds the fibres together.
Yarn twist is measured as the number of turns
per unit of length of a yarn
Twist is expressed as turns per inch (TPI), turns
per meter (TPM) or turns per centimeter (TPC)
TPI affects durability and appearance.
Two types of Twist
S Twist – spiral run upward to the right
Z Twist – spiral run upward to the left
The amount of twist varies with:1. Length of fibres 2. Size of yarn3. Intended use
Fine yarn require more twist then coarse yarns.
More twist in a yarn provide more strength to the yarn.
Low twist in yarn results in a lofty yarn.
Warp yarns need more twist than weft yarns
BALANCED YARN
Balance yarn is one which is having sufficient amount of twist.
If the twist is balanced, the yarn won’t kink back on itself.
It is very easy to work with and does not distort the finished piece.
Balance yarn is softer in feel.
UNBALANCED YARN
Unbalance yarn is one which is generally very highly or unevenly twisted.
The unbalanced yarn generally kink back on itself.
This yarns needs special care and requirements while weaving or knitting.
Unbalanced yarn; like crimp yarn is harder in feel.