Cotton is a natural fiber extracted from cotton plants. It is widely used. Every family has cotton clothes. It is closely related to people's lives. But do you really know cotton? Did you know that it was used in five thousand years BC? Let us have a deep understanding of cotton together.
Cotton is a kind of fiber. Cotton fiber is a seed fiber formed by the elongation and thickening of the epidermal cells of the fertilized ovule, which is different from ordinary bast fiber. Its main constituent material is cellulose. Cellulose is a natural polymer compound with a chemical structure of (C6H10O5)n. The cellulose content of normal mature cotton is about 94%. In addition, it contains a small amount of pentoses, waxes, proteins, fats, water-soluble substances, ash and other accompanying organisms. Because cotton fiber has many excellent economic properties, it has become the most important raw material for the textile industry.
The world's major cotton producing countries include China, the United States, India, Uzbekistan, and Egypt. China currently has the largest unit output and is also the largest consumer of raw cotton. In terms of raw cotton exports, the United States is still the world's number one.
Regionally, China has three main cotton-producing regions, namely Xinjiang cotton area, Yellow River cotton area, and Yangtze River cotton area. Xinjiang cotton area mainly includes Xinjiang and Gansu, and Xinjiang cotton is mainly used in China.
Xinjiang's cotton production accounts for about 50% of my country's cotton production. This area is an irrigated cotton area with sufficient sunshine, arid climate and sparse rainfall; the farming system is one crop a year, the cotton fields are concentrated, the planting scale is large, and the degree of mechanization is high; the yield level is high, and the raw cotton color is good. Xinjiang is the only main producing area of long-staple cotton in China, and its total output currently accounts for more than 30% of the world's total. Different from the decline in the production scale of the world's major long-staple cotton producing countries, Xinjiang long-staple cotton yield/total output has shown a steady increase in recent years. Xinjiang long-staple cotton has excellent quality, and all quality indicators exceed Chinese standards. It is a very top textile raw material.
According to the length of cotton fiber, cotton can be divided into three categories, coarse-staple cotton, long-staple cotton and fine-staple cotton.
Coarse cotton, also called Asian cotton, is native to India. Due to low output and short fibers, they are not suitable for machine weaving and have become obsolete.
Long-staple cotton, also called sea island cotton, is native to South America. Long fiber and high strength are its characteristics, and it is suitable for spinning high-count yarn. The fiber is thin and long, generally the length is more than 33mm, the linear density is about 1.54~1.18dtex (6500~8500 dtex), and the strength is more than 4.5cN. It is of good quality and is mainly used for weaving high-quality cotton yarn finer than 10 tex. Good long-staple cotton also includes Egyptian cotton and horse cotton.
Fine-staple cotton is also called upland cotton, originated in Central America, so it is also called American cotton. Wide adaptability, high output, longer fiber and better quality are its characteristics. It can be spun medium count yarn. The general length is 25~35mm, the linear density is about 2.12~1.56dtex (4700~6400 public branch), and the strength is about 4.5cN. Most of the cotton grown in China falls into this category.
Cotton also has different colors, if we classify cotton by color, there are white cotton, yellow cotton, grey cotton and colored cotton.
White cotton is normally mature and normally spitting, no matter the color of the raw cotton is white, milky white or light yellow, it is called white cotton. Most of the raw cotton used in cotton spinning mills is white cotton.
Yellow cotton is generally low-grade cotton, and only a few applications are used in cotton spinning mills. In the late stage of cotton growth, the boll dies after frostbite, and the pigment on the boll shell is dyed to the fiber, making the raw cotton yellow.
Gray cotton has low strength and poor quality, and is rarely used in cotton spinning mills. The cotton fiber that grows in rainy areas. During the growth and development process or after spitting, if there is more rainfall, less sunshine, and low temperature, the maturity of the fiber will be affected. The raw cotton appears grayish white. This kind of raw cotton is called gray cotton.
Colored cotton refers to cotton that has natural colors. It is cultivated on the basis of the original colored cotton with biological technology such as distant hybridization and genetic modification. Natural colored cotton still maintains the original softness, comfort, and breathability of cotton fiber. The made cotton fabric can reduce a little printing and dyeing process and processing cost, and can avoid pollution to the environment. However, the hue is lacking and the color fastness is not enough. Under observation of stable inheritance.
There are different opinions on the origin of cotton. Some say it originated in India, some say Arab, and some say Mexico. In fact, no one knows exactly the age of cotton. Scientists searching for open bolls in Mexico found boll fragments and cotton cloth fragments that are at least 7,000 years old.
In Pakistan’s Indus River Basin, cotton was grown, spun and woven into cloth dating from 3,000 BC. At about the same time, the indigenous people of the Nile Valley in Egypt were making and wearing cotton clothes.
Arab merchants brought cotton cloth to Europe around 800 AD. When Columbus discovered the United States in 1492, he discovered that the Bahamas had grown cotton. By 1500, cotton was widely known all over the world.
We cannot be sure of the origin of cotton, but we can be sure that the development of cotton is closely related to the Industrial Revolution. Because the American Eli Whitney invented the mechanical gin, it accelerated the development and production of cotton.
(1)Cotton fiber can be made into a variety of fabrics of different specifications (from light and transparent voile to thick canvas and thick velveteen can be made of cotton).
(2)Cotton can be used to make all kinds of clothes, furniture cloth and industrial cloth. Clothes and cloth made of cotton have the characteristics of being strong and wear-resistant, and can be washed and ironed repeatedly (ironing at high temperature). It can quickly absorb and dehumidify, so it will be more comfortable after wearing.
(3)Through other finishing processes, the cotton fabric can achieve anti-fouling, water-proof and mildew-proof effects, and at the same time improve the anti-wrinkle performance of the fabric (reduce the number of ironing of the cotton fabric, even so that it does not need to be ironed, but also Can reduce the shrinkage rate of the fabric when it is washed, so that the shrinkage rate does not exceed 1%).
Cotton seeds can be used to make cottonseed oil, and cottonseed oil can be used to make salad oil and edible oil. After hydrogenation, it can also be used to make ghee and margarine, and the cake residue or seed kernels after oil extraction can also be used as Feed for poultry and livestock.
Approximately 757 million liters of cottonseed oil is used to produce food such as French fries, butter, and salad dressings every year.
Cotton plants have three types of nectaries: leaf veins, bracts, and flowers (the nectaries in the veins of the plant will secrete nectar before the plant blooms), so it can be used as a nectar plant.
With the development of the times, cotton can also be used as a flower arrangement. The flower language people give to cotton is to cherish the people around you.
The reason why cotton has such a long history must have its unique characteristics, and people will continue to use it today. So what are the characteristics of it?
Cotton fiber itself is very soft, and fabrics made of it usually retain that soft feeling.
Cotton fiber has good hygroscopicity. Under normal circumstances, the fiber can absorb moisture from the surrounding atmosphere, and its moisture content is 8-10%, so it touches human skin and makes people feel soft and not stiff. If the humidity of the cotton cloth increases and the surrounding temperature is higher, all the moisture contained in the fiber will evaporate, so that the fabric can maintain a water balance and make people feel comfortable.
Because cotton fiber is a poor conductor of heat and electricity, its thermal conductivity is extremely low, and because cotton fiber itself has the advantages of porosity and high elasticity, a large amount of air can accumulate between the fibers, and air is a poor conductor of heat and electricity, so pure Cotton fiber textiles have good moisture retention. Wearing pure cotton clothing makes people feel warm.
Pure cotton fabric has good heat resistance. When the temperature is below 110°C, it will only cause moisture on the fabric to evaporate without damaging the fiber. Therefore, pure cotton fabric has no effect on the fabric at room temperature, wearing, washing, printing and dyeing. Improve the washability and wearability of pure cotton fabrics.
Cotton fiber has great resistance to alkali. The cotton fiber will not be damaged in the alkali solution. This performance is conducive to the washing of pollution after consumption, disinfection and removal of impurities, and it can also dye, print and print pure cotton textiles. Various processes are processed to produce more new varieties of cotton weaving.
Cotton fiber does not conduct electricity, because cotton fabric does not generate static electricity, it will be more comfortable to wear.
Cotton fiber has good affinity for dyes, easy to dye, complete color spectrum, and brighter color.
Cotton fiber is a natural fiber, its main component is cellulose, and a small amount of waxy substances, nitrogenous substances and pectin. The pure cotton fabric has been tested and practiced in many ways, and the fabric has no irritation or negative effect in contact with the skin. It is beneficial and harmless to the human body when worn for a long time, and has good hygiene properties.
After we have introduced the professional knowledge about cotton, we will briefly introduce how to care for our cotton products, which is closely related to our lives, that is, the washing and preservation of cotton products.
Cotton garments can be washed with various detergents. Before washing, it can be soaked in water for a few minutes, but not too long to avoid color damage.
Cotton fabrics should not be washed with a hard brush or rubbed vigorously to avoid fluffing; do not twist them hard after washing. Do not scald colored fabrics with hot water.
Cotton fabrics are generally not afraid of the sun, but exposure to the sun for a long time will reduce the fastness of the cotton fabrics and easily cause the clothing to fade or yellow. Therefore, the reverse side of the clothing should be aired. During wearing, avoid being stained with acid to cause corrosion and damage.
After washing, drying, and ironing cotton garments, they should be stacked and flat; when storing, avoid dampness, sultry heat, and no ventilation. Uncleanliness in the closet can easily cause mildew.