A simple method to identify the composition of clothing fabric is combustion method. The method is to draw a strand of cloth yarn containing warp and weft at the sewing edge of the garment, ignite it with fire, observe the state of the combustion flame, smell the smell of the cloth yarn after combustion, and see the residue after combustion, so as to judge whether it is consistent with the fabric composition marked on the garment durability label, so as to distinguish the authenticity of the fabric composition.

1、 Cotton fiber and hemp fiber

Both cotton fiber and hemp fiber burn immediately near the flame, burning rapidly, with yellow flame and blue smoke. The difference between the two in the smell of burning and the ash after burning is that cotton burning gives off the smell of paper and hemp burning gives off the smell of plant ash; After burning, cotton has little powder ash, which is black or gray, while hemp produces a small amount of gray white powder ash.

2、 Wool fiber and silk

When the hair is on fire, it smokes and bubbles when burning. The burning speed is slow and emits the burning smell of burning hair. After burning, the ash is mostly shiny black spherical particles, which are broken when pressed by fingers. In case of fire, the silk shrinks into a ball shape. The burning speed is slow, accompanied by a hissing sound. It emits a burning smell of hair fever. After burning, it forms small black brown spherical ashes, which can be broken when twisted by hand.

3、 Nylon and polyester

The scientific name of nylon is polyamide fiber. It is rapidly rolled and melted into white colloid near the flame. It melts and burns in the flame, drops and bubbles. There is no flame during combustion, so it is difficult to continue combustion without leaving the flame, emitting celery flavor. After cooling, the light brown melt is not easy to grind. The scientific name of polyester fiber is polyester fiber, which is easy to ignite. It melts and shrinks near the flame. When burning, it emits black smoke while melting. It is yellow flame and emits aromatic smell. The ash after burning is black brown hard block, which can be broken by fingers.

4、 Acrylic and polypropylene

The scientific name of acrylic fiber is polyacrylonitrile fiber. It softens and shrinks near the fire. After the fire, it emits black smoke and the flame is white. After leaving the flame, it burns rapidly and emits the bitter smell of burning meat. The ashes after burning are irregular black hard blocks, which are fragile by hand. The scientific name of polypropylene fiber is polypropylene fiber. It melts and shrinks near the flame. It is flammable. It burns slowly from the fire and emits black smoke. The upper end of the flame is yellow and the lower end is blue, emitting oil smell. The ash after burning is hard round light yellowish brown particles, which are fragile by hand.

5、 Vinylon and nylon

The scientific name of vinylon is polyvinyl formal fiber. It is not easy to ignite. It melts and shrinks in the near flame. There is a little flame at the top during combustion. When the fibers are melted into colloidal shape, the flame becomes larger, there is thick black smoke and emits bitter smell. After combustion, there are small black bead particles left, which can be crushed by fingers. The scientific name of chloroprene fiber is polyvinyl chloride fiber. It is difficult to burn and extinguishes immediately after leaving the fire. The flame is yellow, with green and white smoke at the lower end. It emits pungent, pungent and sour taste. After burning, the ash is black brown, irregular hard blocks, and the fingers are not easy to twist.

6、 Spandex and fluorine fiber

The scientific name of spandex is polyurethane fiber. It melts and burns near the fire. When burning, the flame is blue. When leaving the fire, it continues to melt and burn, emitting a special pungent odor. After burning, the ash is soft and fluffy black ash. The scientific name of fluorine fiber is polytetrafluoroethylene fiber. ISO organization calls it fluorite fiber. It only melts near the flame, which is difficult to ignite and does not burn. The edge flame is blue-green carbonized, melted and decomposed. The gas is toxic, and the melt is hard round black beads. Fluorine fiber is often used to make high-performance sewing thread in textile industry.

7、 Viscose fiber and copper ammonium fiber

Viscose fiber is inflammable and burns fast. The flame is yellow and emits the smell of burning paper. After burning, there is less ash, which is smooth and twisted ribbon light gray or gray white fine powder. Copper ammonium fiber is commonly known as hukapok. It burns near the flame, with fast combustion speed. The flame is yellow and emits ester sour taste. There is very little ash after burning, only a small amount of gray black ash.