Hemp fibers

A cross-sectional view of hemp fiber is shown in Figure 3b. It has a Z twist in contrast to the S twist of flax. Hemp is regarded as a substitute for flax in yam and twine. Its eadier use in ropes has been replaced by leaf and synthetic fibers. Hemp fiber is used in Japan, China, CIS, and Italy to make specialty papers, including cigarette paper, but bleaching is difficult. The fiber is coarser and has less flexibiUty than flax. 

Hanf-dichtung, /. hemp packing, -faden, m. hemp fiber hemp twine, -korn, n. hemp-seed. 

C. sativa is cultivated for several purposes. Actually, the main legal purpose is the production of hemp fibers and pulp. From these materials paper, clothes and ropes are made [12] and several Western coimtries have already legalized the cultivation of C. sativa for these purposes. In research, the drug-type of C. sativa is also cultivated, however, only for the investigation and determination of forensic studies for chemotype separation. The growth for medicinal purposes is hardly performed, hi the Netherlands C. sativa is cultivated for medicinal purposes under strictly controlled regulations by the company Bedrocan. In this chapter we discuss basic aspects of the cultivation of C. sativa and the optimization of THC content in the plant. 

In 1923 one of Mark s superiors handed him a piece of hemp and asked that he study its molecular structure. Hemp was one of the many natural materials we now recognize as macromolecules which to then defied structural analysis. After much thought and work, also including X-ray studies, he concluded that the hemp fiber contained crystals. On examination, so also did cotton, wood and flax. 

Cannabis is one of civiiization s oidest cuitivated nonfood plants, and does not seem to exist anymore in its wiid form (figure 10.1). In addition to its psychoactive effects, the cannabis plant has also been used for its fibers. Hemp fibers have been found in China dating from 4000 B.C.E., and hemp ropes were dated to 3000 B.C.E. in Turkestan, but it is not certain that cannabis was used for psychoactive purposes at those piaces and times (Schuites and Hofman 1992). 

C. M. Barber, and A. D. Curran. Respiratory symptoms, lung function, and cell surface markers in a group of hemp fiber processors. Am J Ind Med 2001 39(4) 419-425. 

Hemp Fiber (Chanvre in French). The bast-fiber obtained from the plant Cannabis indica or C sativa, which is a perennial herb (Ref 1). The plant is native of western and central Asia, but has long been cultivated in Brazil and tropical Africa, and is now extensively cultivated in many countries. Its fiber is used for preparation of ropes and paper, but was also proposed by Trench (Ref 2), in 1877 to be nitrated to an explosive Refs 1) Daniel (1902), 773 2) Webster s 7th New Collegiate Diet (1969), 388... 

Lignin Nitrate (Nitrolignin). A general term employed to designate nitrated products contg lignin, such as wood, straws, jute, esparto grass, flax and hemp fibers (Ref 1)... 

Waxes from grasses include bamboo leaf wax, esparto wax. and hemp fiber wax. Esparto wax is a hard, tough wax with a melting point of 73-78°C, and is the most important grass wax. Most of the esparto wax produced is consumed In the British Isles. It is chiefly useful as a substitute for camauba. Waxes obtained from roots of various species of plan ts are minute in quantity and of no economic importance. 

Corde a feu or Meche a canon (Fr.) A device used in Europe before the introduction of fulminate primers for igniting BkPdr chges. It consisted of flax or hemp fibers, impregnated with coned solns of substanc es(such as Pb acetate or K dichromate) which would impart, after drying, increased combustibility to the fibers Refs Daniel (1902), 156... 

Charring is known to preserve aspects of the physical structure of wood, seeds, and fruit (42). Srinivasan and Jakes (43) have shown that in charring some aspects of the physical shape of Indian hemp fiber are retained. In the carbonization of wood, Ercin et al (44) report the loss of cellulose, hemicellulose and lignin infrared absorbance bands in the range of 1300-1000 cm-1 and the appearance of two new bands at 1250 cm 1 attributed to the asymmetric C-O-C and at 1450 cm-1 attributed to aliphatic C-H bending. 

Bedstraw dyed common milkweed Indian hemp, charred 10,20 and 30 minutes Indian hemp fiber mineralized for 6 mos. Etowah Mound C 840, partially mineralized bast... 

The comparison between charred and uncharred Indian hemp fibers is more readily apparent in Figure 8, which compares only the 10-minute charred sample and uncharred Indian hemp. It can be seen that some features are lost but some sense that the material is cellulosic can still be observed. 

As the Indian hemp fibers were mineralized in the laboratory, not only did they become encrusted with a green-colored deposit, but their interiors were replaced with copper compounds as well. This is supported by the change in the infrared spectra (45). As the fibers became increasingly mineralized, the infrared absorbance peaks became sharper, and the 817 cm 1, 881 cm 1 and 1045 cm 1 and 1384 cm 1 peaks increased in relative size. 

Etowah Mound C 842 G is a sample from the green encrustation from a very green mineralized fiber. The infrared spectra of these sample fibers show bands that are similar to the laboratory mineralized Indian hemp fibers, but they are sharper (Figure 15). Similarities in infrared spectra between this sample and malachite (IRUG 0057) (19) (Figure 16) indicate that it is primarily malachite. 

Figure 15. Infrared spectrum of Etowah Mound C 842 G green-colored mineralizedfibers compared to that of lab mineralized Indian hemp fibers.

Note The cannabis plant has been cultivated for centuries both for the production of hemp fiber and for its presumed medicinal and psychoactive properties. The smoke from burning cannabis contains many chemicals, including 61 different cannabinoids that have been identified. One of these, A9-tetrahydrocannabinol (A9-THC), produces most of the characteristic... 

After the American Revolution, American settlers continued to grow hemp of excellent quality in the land now known as Kentucky. Hemp fiber continued to be a cash crop, the source of rope that rigged many of the world s sailing ships, and the rugged fabric that covered settlers wagons as they made their way westward. Canvas, another hemp product, was widely used for sails in the shipping industry. A remarkably durable cloth, it is one of the few that seawater does not rot or mildew. (The word canvas is rooted in cannabis. )... 

Kempton, J. B., DeGaetano, D., Starrs, J. E and Rowe, W. F. (1994). Microscopic examination of exhumed wool and hemp fibers from the grave of the victims of Alferd Packer. Biodeterior. Res. 4,465-478. 

Thus, hecogenin and tigogenin are byproducts of the sisal (hemp fiber) industry, sitosterol and stigmasterol are byproducts of the large soyabean industry, and, in the late 1980s, Sarsasapogenin appeared, to Ing. Escobar, likely to become a byproduct of a fledgling Northern Mexico industry in cattle feed, Yucca oil, and other minor products. 

Strangely, the ancient Greeks and Romans paid hardly any attention to the fiber in this plant, although its use for ropes and sails had been introduced from Gaul as early as the third century B.C. It was not until the first century A.D. that Pliny the Elder outlined the grades and preparations of hemp fiber. 

Cannabis saliva, more commonly known as marijuana, is a hemp plant that grows freely throughout the world. The cannabis plant is known most commonly today as a potent psychoactive substance, but for many years it was harvested primarily for its fiber. These strong hemp fibers were employed in the production of rope, clothes, and ship -sails. Although cannabis was used for several centuries in other parts of the world for its mind-altering properties, it was not until the first third of this century that its psychoactivc properties were recognized in the United States. Then the hemp plant was more often harvested for its psychoactive effects. 

The discovery that twisted strands of fiber were much stronger than individual strands was followed by developments in the arts of spinning and weaving fibers into fabric - innovations that ended man s reliance on animal skins for clothing. Here, too, it was hemp fiber that the Chinese chose for their first homespun garments. So important a place did hemp fiber occupy in ancient Chinese culture that the Book of Rites (second century B.C.) ordained that out of respect for the dead, mourners should wear clothes made from hemp fabric, a custom followed down to modem times. 

Ma, the Chinese word for hemp, is composed of two symbols which are meant to depict hemp. The part beneath and to the right of the straight lines represent hemp fibers dangling from a rack. The horizontal and vertical lines represent the home in which they were drying. 

No one knows how Ts ai Lun finally discovered the secret of manufacturing paper from fiber. Perhaps it was a case of trial and error. However, the method he finally devised involved crashing hemp fibers and mulberry tree bark into a pulp and placing the mixture in a tank of water. Eventually, the fibers rose to the top all tangled together. Portions of this flotsam were then removed and placed in a mold. When dried in such molds, the fibers formed into sheets which could then be written on. 

As in China, hemp fiber was highly regarded among the Japanese and figured prominently in their everyday lives and legends. 

The farthest west marijuana fibers have ever been found in the ancient world is Turkey. Sifting through artefacts dating back to the time of the Phrygians, a tribe of Aryans who invaded that country around 1000 B.C., archaeologists unearthed pieces of fabric containing hemp fibers in the debris around Gordion, an ancient city located near present-day Ankara. 

Although the Scythians had contacts with the people of Babylonia, who lived to the west of the Phrygians, no hemp fiber or definite mention of hemp (Cannabis sativa) to the west of Turkey can be found until the time of the Greeks. There are some vague references, however, which may or may not be cannabis. In a letter written around 680 B.C. by an unknown woman to the mother of the Assyrian king Esarhaddon, for example, mention is made of a substance called qu-nu-bu which could be cannabis. 

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