Thread
Presented by
Md. Nur-E-Alam
B.Sc. (L. Products), MBA (Marketing),
M.Sc. (Env. Eng.), Ph.D. (Applied Chem.)
Senior Scientific officer
LRI, BCSIR
1
Thread is a tightly twisted strand of two or more plys of yarn that are circular when cut in
cross section. It is a closing material used to join the components.
The thread should have sufficient strength and suppleness to withstand needle heat
forming during stitch formation.
Thread provides both joining purposes and also gives satisfactory seam appearance to
the product.
There are main three types thread
1. Natural threads---- Come from plants and animals and are spun or
twisted into yarns, e.g., Cotton, silk, wool, jute, ramie, hemp, linen,
etc.
2. Synthetic threads--- are made from various chemicals or
regenerated from cellulose such as wood pulp and cotton waste, e.g.,
nylon, polyester.
3. Blended threads ---- these are the combination of natural and
synthetic threads.
nalam1980@yahoo.com 3
Thread Twist
There are two types of thread twist.
1. “Z” twist--- Anti-clockwise/ Twist-way/ Reverse/ Right.
2. “S” twist----Clockwise/ Weft-way/ Ordinary/ Left.
Thread sizing system
1. Direct system (Fixed Length)------ Higher the number, coarser the thread.
Example: 50 Tex is coarser than the 20 Tex thread.
2. Indirect System (Fixed weight)---- Higher the number, the finer the yarn.
Example: Nm 30 is finer than the Nm 10 thread.
nalam1980@yahoo.com 4
Thread Twist Determination
Holding a thread between the thumb and forefinger of the left hand. With the thumb and
forefinger of the right hand, twist the thread towards yourself.
If the thread tightens it will be a “Z” twist, if the thread loosens or unwinds, the thread will
be “S” twist.
nalam1980@yahoo.com 5
Properties of Threads.
Tensile strength---- The tension at which a thread break. The higher the tensile strength, the
better is the sewing thread.
Seam strength / loop strength-----This is the strength exhibited when one length of
the sewing thread is looped through another and the loops are stressed.
Abrasion Resistance--- Means the sewing thread in seams resists abrasion during the life of
the product.
Mildew Resistance--- A good sewing thread is completely resistant to mildew, fungus
and bacteria, and will not rot even in wet conditions.
Uniform diameter--- Means no variation in thickness.
nalam1980@yahoo.com 6
Shrink Resistance--- Means a sewing thread must remain stable on drying after wash.
Colour fastness--- A good thread gives excellent colour fastness and which is freedom from bleeding and
migration.
Heat Resistance--- During sewing needle generates heat which can burn the thread and the material.
Resistance to high temperature of thread is a desirable property.
Cost---It is not always wise to go for the cheapest available.
nalam1980@yahoo.com 7
Thank You
nalam1980@yahoo.com 8
