Hanma: Excellent Performance Makes Ideal Fiber

In recent years, we have made a thorough exploration of the functional properties of hemp fiber. Supported by a large number of experimental data, we have concluded that hemp fiber has a series of excellent properties.

In recent years, with the improvement of people's quality of life, the trend of pursuing green environmental protection and returning to nature is rising. As a green ecological fiber, hemp fabric has the properties of natural antibacterial, shielding ultraviolet radiation, moisture absorption and sweat elimination, softness and comfort, skin care and cleaning, odor absorption and wear resistance, but also has the properties of dignity, elegance, simplicity Natural and practical style. Therefore, hemp fabric is becoming the ideal fabric in the hands of senior fashion designers.

　　 Moisture absorption and quick drying better than cotton fabric

The strength of hanaf bundle is significantly higher than that of cotton and flax, slightly lower than that of ramie, and its breaking elongation is basically the same as that of other ramie fibers. The bending resistance of Han ramie fiber is between ramie and flax. The torsion resistance is equivalent to that of other hemp fibers.

The length of the single fiber of Han hemp fiber is 15-25mm, and the fineness is 15-30 microns, which is only 1/3 of that of ramie, close to that of cotton fiber.

As the single fiber of Han hemp is relatively short, the process fiber is usually used in textile application, that is, 3~10 fibers are combined together as process fibers for spinning, weaving, printing and dyeing. Although the process fiber is harder than cotton fiber, it gradually splits during processing and use with the decrease of glue between fibers, making its fiber fineness gradually close to cotton fiber, The hand feel is more and more soft, and the wearing is more and more comfortable.

From the electron microscope photos, it can be clearly seen that the end of the hemp fiber is circular, rather than the prickly shape of the ramie, so that even if the fiber is thick, there will be no scratchy feeling like ramie. After degumming, the degree of polymerization of hemp fiber molecules is small (about 70% of flax, half of cotton, and 1/8 of ramie), the fiber cavity is large (about 1/3-1/2 of the cross-sectional area, much larger than ramie, flax, and cotton), and there are a lot of micropores; There are many cracks and holes in the longitudinal direction, and they are connected with the middle cavity. Therefore, hemp fiber has excellent moisture absorption and air permeability. Taking hemp summer cloth as an example, its moisture absorption rate is 7.43mg/min, and its moisture dissipation rate is 12.6mg/min; The moisture absorption rate of hemp ramie summer cloth is 27% higher than that of hemp cotton blended cloth, and the moisture dissipation rate is 32% higher.

In the spring, autumn and winter when the climate is dry, hemp fiber has good warmth retention performance, while it is cool and pleasant in summer. On the one hand, the hydrophilic gene in hemp fiber molecules is easy to combine with water molecules and absorb water molecules. Its loose molecular structure and hollow shape can not only increase the thickness of the air layer, but also fill a large amount of capillary condensation water, making the hemp fiber absorb more and faster moisture; On the other hand, the dense cracks and holes on the surface of hemp fiber are beneficial to moisture dissipation. Therefore, hemp fiber is very suitable for use as a fiber raw material for all kinds of clothing.

The test results show that under the same environmental conditions, the moisture regain of hemp fiber is basically the same as that of cotton fiber. The standard moisture regain of hemp fiber is 7.9%~9.7%, and that of cotton fiber is 7%~8%. The moisture regain of hemp fiber is slightly higher than that of cotton fiber. When the humidity is 65%, the moisture absorption and desorption rate of hemp fiber is significantly higher than that of cotton fiber. Using the same specification of hemp and cotton fabrics, moisture absorption and drying tests were carried out at 100 ℃ and 105 ℃ using a humidity control box and an electronic balance. From the test results, we can see that the moisture absorption and drying rate of hemp and cotton fabrics is significantly higher than that of cotton fabrics.

　　 Provide protective barriers for human health

The hemp fiber has excellent antibacterial and deodorant properties, which is related to its molecular composition and morphological structure. The hemp fiber has a porous structure and strong adsorption performance. Under natural conditions, the hemp fiber will absorb more oxygen, which will damage the living environment of anaerobic bacteria, which makes the hemp fiber have antibacterial advantages in structure. At the same time, the fabric made of hemp fiber can rapidly discharge sweat from the human body, thus destroying the humid environment on which bacteria live and showing bacteriostatic performance. In addition, hemp plants contain a variety of active phenols (THC, CBD, CBN), organic acids (oleanolic acid, ursolic acid, hexadecane acid) and inorganic salts (NaCl), which have obvious killing and inhibiting effects on a variety of bacteria. The Institute of Microbiology and Epidemiology of the Chinese Academy of Military Medical Sciences tested according to the qualitative bacteriostasis method of the American AATCC, the diameter of the hemp fabric to different microorganisms were: Staphylococcus aureus 9. 1mm, Pseudomonas aeruginosa 7.6 mm, Escherichia coli 10 mm, Candida albicans 6.3 mm. At the same time, it has obvious killing and inhibiting effects on Trichophyton gypsiformis, Penicillium, Aspergillus, etc. According to relevant tests at home and abroad, the natural antibacterial rate of hemp fiber against Staphylococcus aureus, Escherichia coli and Candida albicans is more than 99%, and it remains unchanged after 50 times of washing.

After testing, the hemp fiber products also have good anti mold and anti mite properties. The hemp fiber blended towel was tested according to American AATCC30-2004, and no Aspergillus niger grew for 7 days under the temperature of 20 ℃, which has a good mildew prevention effect. The protective performance of bedding made of hemp fiber to dust mites reached 67.07%.

Therefore, hemp fiber products can bring health protection barriers to consumers. The use of hemp fiber can not only develop textile products, but also home textile products, with huge market potential.

　　 Excellent radiation resistance and adsorption performance

Hemp fiber has excellent ultraviolet radiation resistance. One hemp fiber still has a certain lignin content after degumming, which is not found in cotton fiber. Lignin is a natural ultraviolet absorber. Second, the cross section of hemp fiber is irregular triangle, quadrilateral, hexagon, oblate, waist circle or polygon, and the middle cavity is linear or oval. From the molecular structure analysis of hemp fiber, the molecular structure of hemp fiber has spiral lines, multi arris and loose. After the light wave or sound wave is injected, the light wave and sound wave will form diffuse reflection and multi-layer light refraction in the crystal area of the hemp fiber, and will be widely damaged and absorbed in the amorphous area, gaps and holes of the fiber molecules, so that the hemp fabric has a good anti ultraviolet radiation function. The Institute of Physics of the Chinese Academy of Sciences has tested that ordinary clothes can only block 30%~90% of the ultraviolet radiation, while ordinary hemp fabrics can block more than 95% of the ultraviolet radiation without special finishing, and hemp canvas can block 100% of the ultraviolet radiation.

Hanma fiber is a natural fiber, and the cellulose content of Hanma fiber used in clothing is usually more than 95%, so the antistatic performance of Hanma fiber is similar to that of cotton fiber.

Hemp fiber has excellent adsorption properties. The results showed that the adsorption capacity of hemp fiber was much stronger than that of cotton fiber under the same conditions. This is related to its single fiber structure. The porous structure of hemp fiber increases its adsorption area and greatly improves its adsorption performance.

From the analysis of the structural morphology of hemp fiber, it can be found that the hemp fiber is a porous and hollow structure with extremely irregular cross section morphology. This multi longitudinal crack and irregular morphology endows hemp with a large adsorption area, thus showing excellent adsorption performance. In addition, hemp fiber contains trace chemicals, which can react with the chemical components in total volatile organic compounds (TVOC) to improve the adsorption performance of TVOC. (China Textile News)