• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.109-114
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• 2015

In this study, the effects of chlorine dioxide (D) bleaching conditions on the delignification of hemp bast fiber were elucidated. Chlorine dioxide bleaching was carried out through three stages (DED) and five stages (DEDED), respectively. Applied amounts of chlorine dioxide at $D_1$ and $D_2$ stages were varied to find the optimum bleaching condition. It was found that the optical properties of its handsheet as well as the delignification of hemp bast fiber increased as the concentration of chlorine dioxide at $D_1$ stage increased. It was also notable that the bleachability of the DEDED bleaching stages was slightly more effective than that of the DED bleaching stages. The burst index of the handsheets made with bleached hemp bast fiber was higher than that of the unbleached samples, but the burst index of these samples decreased as their delignification increased. These results indicated that the higher concentration of chlorine dioxide at $D_1$ stage was major factor to improve the bleaching efficiency of hemp bast fiber.

• The Research Journal of the Costume Culture
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• v.22 no.1
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• pp.16-27
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• 2014

This study investigated the characteristics of and changes in hemp textile production practices at Gurye in Jeollanam-do in modern times. To do this, in this study, both a literature review and fieldwork research were utilized as research methods. The literature review focused on Gurye's hemp data, and the fieldwork research involved two separate trials. Male and Female residents of Gurye who had experience in the area of hemp production from the 1920s to the 1980s participated in this study. The results were as follows. First, regarding hemp fiber cultivation in Gurye, hemp cultivation continued to the 1970s and there were no changes in hemp cultivation practices during the Japanese colonial-era. Second, there have been very important changes in hemp kilns over time. In the 1950s, there were both single-body kilns and separate-body kilns in Gurye. Later, specifically in the 1950s, a new type of kiln using an iron pot appeared, and the most modern kilns were concrete structures. Third, in Gurye, women cooperatively removed hemp husks immediately after stemming, subsequently bleaching the hemp by soaking it in lye or caustic soda. Over time, there have been changes in ash types and in soaking periods. Fourth, loom types changed from the traditional Korean back-strap loom to the treadle loom in the 1930s- to 1940s. Fifth, since the 1970s, the hemp textile output levels of Gurye have been reduced due to the westernization of clothing styles, the inflow of Chinese hemp fiber and government regulations pertaining to hemp cultivation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.67-74
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• 2004

This study was carried out to investigate the characteristics of handsheets made from nonwoody New-Zealand hemp (Phormium tenax) fibers that was not used before in Korea. The results were as follows : 1. Physical properties of bleached phormium fiber were satisfactory for handsheet forming. Specially, tensile strength was improved by adding bleached phormium fiber. 2. Opacity of handsheet with phormium pulp was fine, therefore it can be useful fiber to improve opacity of light-weight printing paper. 3. Filler retention rate was improved when phormium pulp was added, while drainage time was increased. 4. Phormium fiber has good characteristics as pulp for paper manufacture. So it can be valuable non-wood fiber resource if drainage problem is solved.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.157-160
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• 2005

The surface energies and acid-base interaction between the untreated and treated Jute or Hemp fibers and different matrix compositions of polypropylene-maleic anhydride polypropylene copolymers (PP-MAPP) were investigated using dynamic contact angle measurement. The contribution of the acid-base property into the interfacial adhesion of the natural fibers/matrix systems were characterized by calculating the work adhesion coming from the acid-base interaction. On the other hand, microfailure mechanism of both single Jute and Hemp fiber bundles were investigated using the combination of single fiber tensile test and acoustic emission. Distinctly different micro failure modes of the different natural fiber/polypropylene systems wet ε observed using optical microscope and determined indirectly by AE and their FFT analysis.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.221-224
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• 2008

We made densified wood pellet by hemp woody core as replacing wood resource. Hemp was separated into the bast fiber and the woody core by hot steaming treatment. The hemp woody core had a similar lignin content and carbohydrate composition with hardwood. Also, the hemp had a low ash content, which resulted in a low ash formation in pellet burning. Heating value of the hemp pellet had a very similar to the pellet made by hardwoods. The hemp woody core can replace hardwood for densified wood pelletmaking.

• Fashion & Textile Research Journal
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• v.13 no.3
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• pp.438-444
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• 2011

Bamboo leaves, as natural dye provide unartificial fresh green, are known for expert property at anti-bacterial, anti-aging, anti-oxidation, skin whitening, moisturizing, peeling of horny, deodorizing and some skin disease like as eczema and inflammation without any allergic response. Also, It is quite common to obtain bamboo leaves from our surrounding but most of them were not in use. On purpose of development the way of recycle with common material to dye, bamboo leaves were used to dye on ramie fiber which is valuable for both of apparel and industrial field and investigated their dyeing property. Using extract from bamboo leaves, dyeing property was examined with dyeability, colorimetric property, light fastness and wash fastness under different conditions by extract density, dyeing time, dyeing method and mordants. As results, dyeing was generally colored in yellowish, K/S Value was shown more higher on hemp fiber than ramie. The most optimum dyeing condition was investigated on pre-mordant treatment, dyeing temperature $60^{\circ}C$, dyeing time 30min and extract density 400%. On the treatment with mordant(Al, Fe, Cu), dyebility on both of hemp and ramie fiber were increased by mordant. Especially with Copper(Cu) as mordant, dyebility was highly increased than any other mordants and dyeings showed in deep color. Also on the fastness test which is the most important to natural dyeing, wash-fastness showed good performance with 4-5 grade but light-fastness was above 4 grade on both of hemp and ramie fiber, lower than wash-fastness overall.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.314-320
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• 2022

The function of reinforcing fibers used in building materials is to maintain resistance to bending loads and to function for cracking caused by drying shrinkage. High-density fiber-cement composites are mainly used for linear plates and are used to increase bending resistance. Therefore, tensile properties, bonding strength with cement hydrate, alkali resistance, and the like are required. Recently, as the non-combustible performance has been strengthened, a function to minimize the occurrence of sparks during high-temperature heating has been added. Therefore, the use of organic fibers is limited. In this study, a study was conducted to replace polypropylene used as reinforcing fiber with hemp fiber with excellent heat resistance. Hemp fibers have excellent heat resistance, good affinity with cement, and excellent alkali resistance. Based on the total volume of polypropylene fibers used in the existing formulation, the non-combustible performance was compared and evaluated by using hemp fibers instead of the polypropylene fibers, and basic physical properties such as flexural strength were tested. As a result of conducting a non-combustibility and physical property test using hemp fibers with a fiber length of 7 mm using 2 % and 3 % by weight, it was found that there is no remaining time of the flame, and the flexural strength can be secured at 95 % level of the existing polypropylene fiber.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.42-45
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• 2005

Interfacial evaluation of various combinations of both Flax and Hemp fibers/polypropylene were performed by using micromechanical test and nondestructive acoustic emission (AE). It can be because interfacial adhesion between the natural fiber surface and matrix plays an important role in controlling the overall mechanical properties of polymer composite materials by transferring the stress from the matrix to the fiber. It is necessary to characterize the interphase and the level of adhesion to understand the performance of the composites properly. Microfailure mechanism of single Flax fiber bundles were investigated using the combination of single fiber tensile test and nondestructive acoustic emission. Microfailure modes of the different natural fiber/polypropylene systems were observed using optical microscope and determined indirectly by AE and their FFT analysis.

• Korean Journal of Plant Resources
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• v.8 no.1
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• pp.89-94
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• 1995

The physiological variation and major characteristics of the collected hemp from Mokpo and Suwon region are studied for the basic materials of hemp dioecism's developmental rate adjustment and the physiological function. The results ate following. Female's flowering date in Aug., 10, and male’s in July, 26. In sex ratio, The collected hemp from Mokpo is $47{\sim}53%$ and Suwon in $49{\sim}51%$. The correlation between many other charaoters and sex ratio Show a negative correlation in male. Flowering date, stem diameter, fresh stem yield and hemp skin yield show a psitive correlation. Fiber leght and hemp skin yield show a negative correlation.

• 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.