Thread is a tightly twisted filament of two or more plies of yarn that are circular when cutting in cross section. 95% of sewing thread is manufactured for the commercial and industrial purposes. Usually, thread is spinning on spools or large cone that is marked on their ends with the size or fineness of the thread. Currently, thread manufacturers produce several categories of thread for different purposes with thousands of colors. Various improvements of thread industry have given a wide variety of choices along with greater quality.

Types of Sewing Threads:
Sewing threads are usually produced from either natural/organic or man-made/artificial fibers in filament or staple form. On the basis of utilization sewing threads, classification has been given underneath by a sketch for easy understanding.

Thread Types
Thread Construction/Structure: There are some thread constructions produced for sewing threads:
(1) Spun sewing thread
(2) Filament sewing thread
(3) Core spun
(4) Air entangled
Spun Thread: They are made from staple fibers and undergo twisting to form single and simple yarn. They may be further twisted to generate multiply sewing thread. The number of plies may vary from two to six. It has excellent stability, but abrasion resistance varies on the type of fiber content. Spun polyester yarns are now the most popular and cheap. It is stronger than comparable cotton spun thread.
Filament Thread: Comparable filament threads are stronger than spun threads. There are three types of filament threads:
(1) Smooth multi-filament threads are made of polyester or nylon. These are very strong threads are find application where high strength is a requirement. Thus, they are suitable for sewing shoes, leather garments, leather bags etc.
(2) Textured Filament thread: It is a polyester thread and finds application in the lopper thread for cover stitches. It cannot be used as needle thread as it increases friction. QQ thread is one of the examples of this item.
(3) Mono-filament thread: This is produced from a single continuous fiber. It’s neutral and translucent color is compatible with most of the fabrics. This thread is quite strong and uninformed, but thread breakage is minimal. It has low flexibility and tends to unravel from the seam.
Core spun Thread: This thread combines staple and filament thread. It generally has multi-ply construction. The core is made up filament fiber, and staple fibers are wrapped around the core. It is an attempt to get the strength of core filament polyester and to cover contributes to sew-ability. Cotton Polyester Core spun requires two dye baths and so leads to higher cost.
Air entangled Thread: This is a very interesting thread and was designed quite recently. In this thread polyester was given no twist. So the thread allows sewing in any direction, and there is no hazard in affecting twist. This thread is compatible with other polyester thread and can be used for any apparel.
Specialty threads: These are threads which are required for special purposes. Embroidery threads, monogramming thread, heat, and flame retarding threads are examples. Rayon previously enjoyed monopoly use because of excellent luster, color, and low cost. But spun polyester has greatly replaced embroidery and monogramming threads because the latter has higher tenacity, abrasion resistance, and resistance to chemicals.
Twist: Twist is an elementary process for producing threads from the fiber. Threads are formed when a number of fibers undergo twist. Twist is the number of turns per cm of the thread.
Too low twist may make the thread break and fray while too strong twist makes the threads strong sometimes resulting in knots that make stitching difficult.
Thread Color: Thread color is very important because it must match with the piece goods. Poor color fastness may make the thread unacceptable and unusable. Thread color fastness refers to fastness to light and washing. Color fastness is also affected by abrasion, chemicals, dry-cleaning etc.
Thread lubrication: Some appropriate lubrication is used to reduce friction and build up of needle heat. The lubricant must be non-soiling, non-staining and must not affect thread color.

Thread Size: For a long time thread was measured in this country in English Count. In the US and other world markets, thread size is measured in ticket number. There are other sizes, such as Tex, Denier, Metric Count and English Count Etc. The ticket number system is multiple, traditional yarn sizing system into a single, comparable sizing system.Sewing Thread

 The finer the thread is equivalent to the higher the ticket number. The table shows the relationship between thread sizes, thread weight, and needle size.

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Usually, production process of almost all types of threads is fully automated. Product manufacturers place considerable demand on thread makers to produce something better than the quality of thread and to make suitable for a purpose on its demand of the workplace. Thread must come out from the factory with an excellent combination of performance characteristics. Thread functions are not only to make cloth but also to protect us. Moreover, we depend on the thread in products like shoes, parachutes, and automobile safety belts to protect us throughout the life of the product.

In the coming future, thread manufacturers will continue to modify and invent new types of fiber and clothing to meet the demand of fashion conscious people. Creative thinkers may guess its varieties will become antiquated, but the consumer wants to express personality through a new dimension of clothing for a variety of activities and trend. This clothing for various activities is sewn with specialized threads.