• Fibers and Polymers
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• v.6 no.1
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• pp.6-12
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• 2005

Fiber surface morphologies and associated internal structures are closely related to its properties. Unlike other fibers including cotton, bast fibers possess transverse nodes and fissures in cross-sectional and longitudinal directions. Their morphologies and associated internal structures were anatomically examined under the scanning electron microscope. The results showed that the morphologies of the nodes and the fissures of bast fibers varied depending on the construction of the inner fibril cellular layers. The transverse nodes and fissures were formed by the folding and spiralling of the cellular layers during plant growth. The dimensions of nodes and fissures were determined by the dislocations of the cellular layers. There were also many longitudinal fissures in bast fibers. Some deep longitudinal fissures even opened the fiber lumen for a short way along the fiber. In addition, the lumen channel of the bast fibers could be disturbed or disrupted by the nodes and the spi­rals of the internal cellular layers. The existence of the transverse nodes and fissures in the bast fibers could degrade the fiber mechanical properties, whereas the longitudinal fissures may contribute to the very rapid moisture absorption and desorption.

• Fibers and Polymers
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• v.7 no.1
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• pp.26-29
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• 2006

Samples of kenaf (Hibiscus cannabinus) grown in Malaysia were examined to determine the kraft pulp and paper-making properties of their bast (or bark) fibers. Using kraft pulping process showed that bast fibers were relatively easy to cook resulting good pulp yields in the range of 45-51 %. The bast pulp produced sheets with great density, tear index and dry zero-span breaking length. Kenaf bast fiber is considered promising for production of high-grade printing, writing and specialty papers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.70-76
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• 1999

This study was to measure the potential of nonwoody fibrous material, kenaf. Whole stalk of kenaf, Hibiscus cannabinus was separated by two parts of bast and core portion, and cooked separately by alkaline method. Morphological characteristic was evaluated using confocal laser scanning microscope (CLSM) and fiber quality analyzer(FQA). The strength properties of handsheets, made by different mixing ration between kenaf base and core fibers, were measured. Cross-sectional area of bast fibers was smaller than that of core fibers, but the bast fibers had a thick cell wall and narrow lumen area. Bast fibers were longer in length than core fibers. Core fibers had thin cell walls, broad lumen areas, and short lengths, and they had collapsed shape even in water. These characteristics of core fibers affected strength properties of handsheet positively. When the amount of core fibers increased, the strength properties of handsheet were increased. When the amount of bast fibers increased, the handsheet had rougher surface and higher air permeability.

• Journal of Korea Foresty Energy
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• v.20 no.1
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• pp.6-11
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• 2001

In order to use bast fibers of mulberry tree at a pulp source of Hanji, the bast fibers were microbiologically treated with several wood rot fungi, and the microscopic characteristics of bast fibers depending on treatment days were evaluated. By wood rot fungi, Phanerochaete chrysosporium and Trametes versicolor, the weight reduction ratio was approximately 50 percent within incubation for 20 days. occurring together with decomposition of useful fibers. However, Hwterobasidion insularis and Stereum hirsutum have completely decomposed the utmost layer of black blue colored bast fibers, and not caused the damage if fibers. Until incubation for 10 days, the cellulose content of vast fibers by Stereum hirsutum was 78.9 percent with lignin content of 7.2 percent, showing an appropriate decomposition for useful fibers. By microscopic observation, the bundled fibers were separated to single fiber within treatement days 30 by Pleurotus ostreatus, and there were no damage on the surface of fiber by treatment days 50.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.47-54
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• 2009

Anatomical characteristics of kenaf were investigated in transverse, radial and tangential direction by optical and scanning electron micrograph. Kenaf was made up of bast fibers, wood fibers, vessels and parenchyma cells. Bast fibers were long slender cells with different types of pits. The shape of wood fibers were in various ways and pointed at the ends. The pits were observed on the surface of bast fibers. Kenafs were diffuse and radial porous. and composed of solitary pores and two or three radial pore multiples. Various types of vessels were observed. The pits showed alternate pitting and larger diameter than other cells. Parenchyma cells were rectangular or square with different shapes of pith parenchyma cells compared to conventional types of parenchyma cells in wood. The number of pith on the surfaces were small.

• Fibers and Polymers
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• v.5 no.3
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• pp.171-176
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• 2004

Fiber fineness characteristics are important for yarn production and quality. In this paper, degummed bast fibers such as hemp, flax and ramie have been examined with the Optical Fiber Diameter Analyzer (OFDA100 and OFDA2000) systems for fiber fineness, in comparison with the conventional image analysis and the Wira airflow tester. The correlation between the results from these measurements was analysed. The results indicate that there is a significant linear co-relation between the fiber fineness measurement results obtained from those different systems. In addition, the mean fiber width and its coefficient of variation obtained from the OFDA100 system are smaller than those obtained from the OFDA2000 system, due to the difference in sample preparation methods. The OFDA2000 system can also measure the fiber fineness profile along the bast fiber plants, which can be useful for plant breeding.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.3
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• pp.49-59
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• 2009

The bast fibers of paper mulberry were dyed by using sappan wood, gardenia, and gallnut extracted under various extraction conditions. The surface absorption rates, color, and sunlight fastness of the dyed fibers were compared to those of the dyed cotton and silk. The K/S values of silk showed the highest values, followed by gallnut, gardenia, and sappan wood. The optimum extraction conditions of the dye materials were 20 g/L (input amount of dye materials per liter), $90^{\circ}C$ (extraction temperature), and 30 minutes (extraction time). The values of saturation were observed to increase with the increase of the amount of dye materials, extraction time, and extration temperature. However, no effect were found on the values of hue and lightness. In all samples, the developed colors dyed by sappan wood and gardenia were the series of YR, and Y, respectively. The colors of dyed cotton and bast fibers of paper mulberry by gallnut were the series of Y and the dyed silk showed the series of YR. The values of saturation of the bast fibers of paper mulberry by sappan wood and gardenia showed the highest values of saturation, followed by cotton, and silk. In the case of gallnut, cotton showed the highest values of saturation, followed by the bast fibers of paper mulberry, and silk. The sunlight fastness were not improved in all dyeing conditions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.44-50
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• 2002

This research was performed to investigate the physical properties and color appearance of Hanji manufactured using bast fibers dyed separately by two reactive dyes with different colors. The breaking length of color Ha was above 7 km. The fastness was five grade; the use of reactive dyes made the color of the Hanji not to be faded away. The Hanji manufactured by mixing uniformly two types of bast fibers separately dyed showed the mixed color of two different colors. However, the shives showed their original colors, resulted in irregular color patterns all over the sheets. The color of color Hanji with different colors in the front and back side of sheets showed color difference between front and back side of the sheets. Accordingly, the color of the sheet has a reflection from the backside, resulted in Pink. The colors of the Hanji appeared in this study could not be found from the Hanji manufactured by traditional methods.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.154-163
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• 2015

Because of acute or chronic intoxication by carbon disulfide, viscose rayon industry is strictly subjected to environment regulatory approval. Recently, non-wood fibers are frequently considered as a raw materials for the manufacture of specialty paper for the higher physical strength and functionality. Among the non-wood fibers, hemp bast fiber is one of the most widely used materials in viscose rayon yarn industries. In this study, the handsheet for manufacturing the viscose rayon yarn was prepared with wood pulp fibers and hemp bast fibers. The proper mixing ratio of wood fibers and hemp bast fibers with dry-strength agent and nano-celluloses was analysed in terms of physical and mechanical strength of sheet for viscose rayon yarn. The papermaking conditions for high mechanical strength of sheet were obtained by mixing the SwBKP and HwBKP fibers with freeness level of 200 mL CSF. The dual polymer system by controlling the addition ratio of PVAm and anionic PAM was also important. The addition of nano-cellulose into wet-end furnishes increased the physical strength of sheet, and improved the paper structure for the production of viscose rayon yarn.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.51-61
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• 2012

The new alkali pulping process combined with electron beam treatment was applied to utilize hemp bast tissues as a new valuable fibrous resource. Hemp bast tissues have some chemical properties with high lignin contents and holocellulose not to be defiberized by alkali pulping only, compared with the bast tissue of paper mulberry. To make up for the weakness of traditional alkali pulping process, electron beams were directly irradiated into the swelled bast tissue of hemp in NaOH solution and distilled water, and then facilitated the defiberization of hemp bast tissues. The papermaking from hemp bast fibers manufactured by the combination pulping process showed good apparent density, formation structure and air permeability, and had some mechanical properties with lower tensile, tear, burst strength and folding endurance. It is finally concluded that the combination pulping process with electron beam treatment could be suggested a new alternative for non-woody fibers.