Sewing thread is the thread required for knitted clothing products. Sewing thread can be divided into three categories according to raw materials: natural fiber, synthetic fiber sewing thread and mixed sewing thread. With the development of the polyester industry, more and more pure polyester fibers are used as raw materials for sewing threads.
　　Polyester fiber is a kind of high-quality synthetic fiber. It is used to make sutures with high strength. It ranks second only to nylon threads in all kinds of sutures, and it does not reduce the strength when wet. Its shrinkage rate is very small, and the shrinkage is less than 1% after proper shaping, so the sewing stitches can always remain flat and beautiful without shrinkage. Abrasion resistance is second only to nylon. Low moisture regain, good high temperature resistance, low temperature resistance, light resistance and water resistance. Therefore, polyester thread is an extremely widely used variety, replacing cotton sewing thread in many occasions. Polyester thread has a wide range of uses, and can be used for garment sewing of cotton fabrics, chemical fiber fabrics and blended fabrics, as well as for sewing knitted outerwear. The special polyester thread is also an excellent thread for the shoe and hat leather industry.
　　Polyester is also called high-strength thread, nylon sewing thread is called nylon thread, usually called (pearl thread) polyester sewing thread is twisted with polyester long fiber or short fiber, wear-resistant, low shrinkage, and good chemical stability. However, the melting point is low, and it is easy to melt at high speed, block the needle eye, and easily break the thread. Due to its high strength, good wear resistance, low shrinkage rate, good moisture absorption and heat resistance, polyester thread is resistant to corrosion, not easy to mildew, and not moth-eaten, etc. It is widely used in garment sewing of cotton fabrics, chemical fibers and blended fabrics due to its advantages. In addition, it also has the characteristics of complete color and luster, good color fastness, no fading, no discoloration, and sunlight resistance. The difference between polyester sewing thread and nylon sewing thread: polyester ignites a lump, emits black smoke, smells not heavy, and has no elasticity, while nylon sewing thread also ignites a lump, emits white smoke, and has a stretchy smell when pulled. Heavier. High wear resistance, good light resistance, mildew resistance, coloring degree of about 100 degrees, low temperature dyeing. It is widely used because of its high seam strength, durability, flat seam, and can meet the needs of a wide range of different sewing industrial products.
　　The specifications of sewing thread are 202203302303402502403602604606209, etc. Among them, 202604 is the same product (basically the same thickness), 203 and 206 are also the same product (basically the same thickness), What is the standard called? For example, the 402 standard is 40S/2, the 604 standard is 20S/2, and so on.
　　Sewing thread refers to the thread used for sewing textile materials, plastics, leather products and sewing books and periodicals. Sewing thread is characterized by sewability, durability and quality appearance. Sewing threads are generally divided into three types due to their different materials: natural fiber type, chemical fiber type, and mixed type; the characteristics of sewing threads also have their unique properties due to their different materials:
　　Cotton sewing thread---good heat resistance, poor elasticity, abrasion resistance, moisture resistance and antibacterial ability, suitable for high-speed sewing and durable pressing. The most used is the long-staple pure cotton thread: it is made of long-staple cotton, which is combed, singeed, mercerized, and twisted at a high density, so the tensile force is better than that of ordinary combed pure cotton. Often used for pure cotton clothing and other pure cotton fabrics for sewing purposes Specifications 20/2 (60/4), 20/3 (60/6) 40/2, 40/3, 20/9 pure cotton threads: generally divided into common Combed and combed two parts, the real 100% cotton thread can be used for sewing is fully combed cotton. Generally, 402, 202, and 203 are used. It is combed and singeed from high-quality cotton in the cotton area. Pure cotton thread is often used for sewing of pure cotton clothing and other pure cotton fabrics.
　　Polyester sewing thread---high strength, flat and beautiful stitches, wear-resistant; no mildew or rot, low price, rich colors, not easy to fade, not shrinkage.
　　Polyester-cotton sewing thread---It is made of 65% polyester staple fiber and 35% cotton fiber blend. The thread has high strength, good wear resistance, small shrinkage rate, good flexibility and elasticity, and good heat resistance. Various garments can be sewn.
　　Nylon sewing thread---Strong elongation, good elasticity, smooth texture, silky luster, excellent wear resistance.
　　Nylon thread---high breaking strength, good wear resistance, low hygroscopicity, high elasticity, but not enough heat resistance, generally controlled at about 120 ℃. Generally used for sewing chemical fiber fabrics, woolen wool, sweaters, etc.
　　Vinylon thread---low price, high breaking strength, lower abrasion resistance than nylon thread, good chemical stability, mainly for sewing all kinds of flour bags, cloth rubber shoe uppers, canvas, buttonholes, buttons, etc.
　　Silk thread---smooth surface, soft luster, good elasticity and high temperature resistance. It is used to sew woolen garments and satin fabrics; rayon has bright colors, but has poor strength, poor hygroscopicity and relatively cheap price. Mostly used for machine embroidery.

Sewing thread is a basic raw material for giving desired shape to a garment and holding the body parts together by creating seams. Sewing thread is a very important item for tailoring shops, industrial garment manufacturers and fashion houses. It has both functional and aesthetic properties.

Besides, sewing thread is also used in the automotive industries for making car seats, airbags, seat belts and the vehicle interior design. Sewing thread is used in the footwear industries and embroidery industries as well.

Sewing thread can be made of staple fibre or continuous filaments by twisting hardly or slightly. Two or more filament yarns are twisted together to make sewing threads. Sometimes single filament is also used. Natural or synthetic or blended fibers can be used to make sewing threads too.

If we talk about closing and top stitch seams then core spun sewing threads are perfect which can give outstanding quality seams. For over locking or cover stitch seams continuous bulk filament sewing threads are perfect. For high quality denim garment, natural and synthetic fibre blended core spun sewing threads are perfect for closing seams. For achieving perfect seam strength for leather goods, continuous filament sewing threads are perfect.