Industry Knowledge: Identification Of Natural Fibers Such As Cotton, Wool, Silk, Hemp And So On.

At present, there are more and more new fabrics on the market. Some are made of natural fibers such as cotton, wool, silk and hemp. Some are made of chemical fibers, and others are made of several kinds of fibers. In order to maintain good textiles, prolong their service life and reasonably guide consumers' consumption, we should master the identification of textiles.

There are many methods for regional textiles, such as sensory method, combustion method, microscopic observation method, chemical reagent analysis method and specific gravity method. The following is the identification of sensory identification and combustion.

1. Sensory identification

Sensory identification refers to the identification of fabrics by hand touching, seeing, hearing and hearing. This is the easiest and most commonly used method of identification. Sensory identification is mainly based on hand feeling, visual recognition of fabric softness, elasticity, gloss and crease, and then observe the length, intensity, thickness and bending characteristics of fibers extracted from fabric yarn.

(1) cotton fabric: there are NEP impurities on the surface of the ordinary fabric. Carefully observe the surface is furry, and hand clenched fabric has crepe; draw out the fibers in the yarn to observe, the fibers are very short, irregular, generally not more than 38 millimeters; hand touching fabric has a warm feeling, elasticity is worse than wool.

(2) woolen fabric: wool feels slippery and waxy, rubbing with less crepe, good elasticity, light softness, no Aurora; pulling out the fibers observed in the fabric, wool is usually curly (commonly known as Mao Bo) state, longer than cotton, usually more than 40 millimeters, and hand touching fabric feels warm and warm.

(3) silk fabric: silk fabric is thin, soft, smooth and glossy; the silk drawn from the fabric is long, thin and strong, and the hands touch the feeling of sticky hands.

(4) linen fabric: the fabric feels rough and hard, lacks elasticity and luster. The fibers in the fabric are observed, fiber is thick, long and flaky, and the intensity is strong.

(5) viscose fiber fabric: the fabric has no impurities on the surface, gloss is good, rubbing when the crepe is more; draw out the fabric in the fiber observation, fiber neat, longer than cotton (usually more than 40 millimeters), after the water is thicker (thick) hard, easy to break, broken fiber is more neat, but there are scattered cilia. In addition, viscose fiber is colourful, so all kinds of flowery and colorful slippery are usually made of viscose fiber.

Viscose fabric and cotton fabric difference: viscose fiber fabric strength is low, especially after the water wet strength is lower, and the rapid expansion, thickening and hard, easy to tear in the water wet place, and cotton fabric has no such characteristics, viscose fiber impurities, fiber length, neat, gloss, yarn yarn dry uniform; touch viscose fiber fabric with cold and hard hair feeling, but after rubbing, there is a soft feeling of soft, fabric after wearing, easy to hair, wrinkle more, easy to deformation. Cotton fabrics are better than them.

The difference between viscose fiber fabric and silk fabric: viscose fiber strength is smaller than silk, silk fabric moisture after wet strength, hardness and dry no obvious changes, so the strength of its fabric, whether in dry or wet when it is larger than viscose fiber fabrics; the two quickly relax after holding tight, crepe is more viscose fabric, less is silk fabric; in addition, after two pieces of fabric soaked, thickened and hard, easy to tear is viscose fiber fabric.

(6) synthetic fiber fabrics: the strength and elasticity of general synthetic fabrics are good, the handle is smooth and bright, but not too soft. Except for acrylic fabric, the squeaky field can be produced when hand rubbing. The rest of the fabrics are difficult to distinguish by sensory methods.

2. Combustion identification

Combustion identification is based on the different characteristics of the fabric during combustion, such as the size of the flame, the speed of the combustion and the color of the flame, the smell of burning, the shape and color of the ashes.

(1) cotton fabric: the yarn thread is extracted from the fabric and ignited. The burning speed is fast and the flame is yellow. When the flame goes out, Mars can continue, the smell is similar to the burning paper, and the ashes are very few and gray.

(2) woolen fabric: curl when burning, slow burning rate, smoking, firing, leaving fire, and smelling like burning hair, ash is massive and fragile.

(3) silk fabric: when it is burning, it is curled into clusters, and the flame is orange. It is extinguished from the fire. The smell is just like the singeing hair, and the ashes form a black block with slight hardness.

(4) linen fabric: the speed of burning is slightly slower than that of cotton fabric, and the flame can not continue to burn after the flame is extinguished.

(5) viscose fabric: the characteristics of combustion are the same as that of cotton.

(6) nylon fabric: when it burns, it first curl up, melt, smoke white, and then slowly burn. The flame is small and smoky, the flame edge is blue, and there are drops of melted matter, and there is a sound. It can take heat while spinning, and smoke black smoke. The smell is similar to the smell of burning paint, the ashes are black, and the bright and hard spheres are not easy to crush.

(7) polyester: when first burned, it first curled and melted into a glassy state, taking advantage of the potential to draw silk. Later, the flame was bigger. At the same time, the black brown melts were produced at the base, producing sparking sparks and squeaks. The smoke and dust in the black smoke came down, and the ashes formed black balls. The texture was hard and hard to crush.

(8) acrylic fiber: when burning, it first melted, the speed of combustion was fast, the flame was bigger, there were flashes and noises, black smoke and spicy smell, and then became black and lumpy and crushed easily after burning.

(9) vinylon: when burning, the edges shrink and burn, and the burning material changes from white to yellow to brown. When the initial combustion occurs, the flame is smaller and smoke-free, and then the flame gradually increases. The base is flashing, emitting black smoke and pungent odor, which is similar to the smell of calcium carbide. The ash is black and massive and easy to crush.

(10) polypropylene: slowly burning along the melting side, with candle odor, small flame, no ashes; the remaining part is transparent ball, and it is not easy to crush.

Identification of several major textiles

(1) silk

Silk is divided into two kinds: raw silk and chemical fiber. Silk fabric is made from silk. Its common characteristics are high moisture absorption, good air permeability, smooth and soft texture, elasticity, natural luster and bright and soft silk. Ignite silk fibers with slow burning speed and burning hair. The thread is twisted and the filament is continuous. It's comfortable and cool. Commercially available synthetic silk fabrics are made of synthetic fibers, some of which are synthetic fibers and silk blended, or pure man-made fibers and synthetic fabrics. After special treatment, the surface is similar to silk. Silk fabrics are easy to wash, dry and shrink, and have poor breathability and hygroscopicity. Rayon silk fabric feels sticky and rough, silk surface is wrinkled, glossy and dazzling, colorful, low shrinkage, monofilament is thicker and flat, when broken, the head is neat, wetter, easier to tear, ignited fiber burning paper or vinegar taste. Synthetic fiber silk fabric is smooth, elastic, bright and dazzling. It is not easy to wrinkle. The shrinkage rate is less than 5%, the thickness of the monofilament is uniform, and it is not easy to tear. The smell of igniting fibers is different from that of silk fabrics.

(two) cashmere

Cashmere is a fine fuzz from cashmere goats (also known as cashmere goats). It looks natural, glossy, soft, soft, light, warm, slippery, elastic and glossy, and is known as "the king of fibers". As the output of cashmere is only 1% of the whole world, the price of cashmere is more than ten times that of wool. It is the most precious animal fiber.

Cashmere fiber is short in length and low in strength. The scales covered by fiber surfaces are thin and thin, closely attached to each other. Because the number of fibers is less than that of wool, the friction coefficient is less than wool, so the cohesion between fibers is poor, fiber is smoother, and the shrinkage is less than wool. Cashmere fiber curls less, but the crimp depth is large, so cashmere products are better than wool in terms of warmth retention. Cashmere is easier to absorb moisture than wool under the same temperature and humidity. Within a few seconds of water, cashmere fibers can be soaked and the wool will take a few minutes.

Because cashmere fiber is thinner than wool, cashmere fabric is easy to pilling, cashmere yarn is low in strength, and fastness is less than wool. When wearing, it should avoid contact with hard objects. Because cashmere fiber is easy to absorb moisture and is easily moth eaten, it should be washed and stacked and stored in plastic bags with insect repellent or several holes.

The "sheep cashmere" sold in the market has nothing to do with cashmere. "Sheep's hair" is actually wool, fineness of 20~40 micron, length of 50~200 microns, but only a little more than ordinary wool, sheep only produce wool instead of velvet.

(three) identification of flax and ramie

Flax fiber is the first natural County Committee that people have discovered and used. Because of its natural texture and elegant and simple colors, and its anti ultraviolet function, it has no irritating effect on human skin, and has good heat dissipation function and certain inhibition of bacterial function. It is favored by consumers from wearing and using. The higher the yarn of linen products, the more smooth and bright the surface is, the less the grain on the surface, the better the sense of draping, the more slippery, the better the quality.

Some linen garments are very stiff on the body and harden after launching. This is the characteristic of ramie products. Distinguish between the two can be tested from three aspects: first, appearance, ramie products are obvious wrinkles, sharp edges, flax products wrinkled larger, naturally, and will slowly disperse; two is cloth, ramie structure is very loose, the gap between the warp and weft lines is large, flax fabric structure is full, draping is particularly good; three, when water is encountered, ramie products harden, and linen products are very soft. Linen fabrics can absorb ultraviolet rays, but not for long time. Wash with washing machine, but do not dehydrate, so as to prevent wrinkles from ironing.