• 펄프종이기술
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• 제31권2호
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• pp.42-49
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• 1999

Although many researches have been made on the adsorption of cationic starches onto chemical pulp fibers, only limited studies have been reported for deinked pulp(DIP) and thermomechanical pulpI(TMP). In this experiment, the adsorption behavior of the cationic starches onto DIP and TMP fibers investigated. Almost complete adsorption of cationic starches onto the pulp fibers were observed when the addition rate of starch was low. Adsorption ratio decreased abruptly when 3.5% and 4.0% of cationic starches were adsorbed onto deinked pulp and thermomechanical pulp, respectively. Adsorption of cationic starches increased as the degree of substitution decreased and as the pH of the pulp slurry increased. TMP fibers adsorbed more cationic starches than DIP because of its greater charge density, and this led to greater improvement in strength properties for the TMP sheets.

• Fibers and Polymers
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• 제7권1호
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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.

• 펄프종이기술
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• 제46권4호
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• pp.11-20
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• 2014

The objective of this study was to investigate the beating properties of two types of cotton pulps such as "cotton lint mixed pulp" and "cotton linter pulp". In order to improve refining characteristics, the effects of carboxymethyl-cellulose (CMC) pre-treatment, mixing ratio changes of cotton lint mixed pulp and cotton linter pulp, and refining load changes were analyzed. In mill application, it was possible to improve the refining characteristics and maintained the strength properties of the paper by applying increasing ratio of cotton linter pulp mixing and controlling the refining methods.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Proceedings of Pre-symposium of the 10th ISWPC
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• pp.84-89
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• 1999

Treatment with the enzyme pectinase has been reported to lower the cationic demand of thermomechanical pulp(TMP) bleached with alkaline peroxide in the laboratory. We have extended this discovery to bleached TMP produced industrially, and shown that commercial enzyme preparations can treat pulp within 15 minutes at the at the temperature and pH values prevalent in paper mills. About half of the cationic demand in the bleached pulp can be destroyed by pectinase. Dynamic drainage jar experiments show that the enzyme treatment improves the effectiveness of several cationic polymers to increase retention in the absence of retention aids or with non-ionic polymers, and does not damage the strength properties of the pulp. Pectinase could be easily incorporated into paper machine stock preparation systems to lower the charges of cationic retention aids needed in furnishes containing peroxide-bleached mechanical pulp.

• 펄프종이기술
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• 제47권6호
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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.

• 펄프종이기술
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• 제39권4호
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• pp.45-52
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• 2007

Whole, bast and core fibers of kenaf cultivar Tainung-2 were pulped under different pulping methods, thermomechanical and kraft pulping methods. The physical and optical properties of kenaf TMP(thermomechanical pulp) and KP(kraft pulp) handsheets were investigated and the results from the study are summarized as follows: Yields of TMP and KP were $77{\sim}87%\;and\;43{\sim}52%$, respectively. There was no significant change in apparent density between kenaf KP and USKP(unbleached softwood kraft pulp) but TMP showed a little lower apparent density. Bast pulp had the lowest apparent density regardless of pulping methods. Tensile strength of kenaf KP was higher than that of TMP but similar to that of USKP. Both TMP and KP handsheets of bast fraction showed the highest tear strengths among whole, bast, and core fractions. Core fraction showed the lowest tear strengths under different pulping methods. In general burst strength of kenaf pulp under different pulping methods was lower than that of USKP, and kenaf pulp had better stiffness than USKP. Brightness of kenaf KP and TMP was higher than that of USKP. There was no significant variation in opacity between kenaf pulp and USKP even though kenaf pulp showed a little lower opacity. The main difference in paper quality between the core fiber and bast fiber is derived from the fact that bast fiber is long and thin, whereas core fiber is short and thick.

• 펄프종이기술
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• 제47권3호
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• pp.55-62
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• 2015

Paper mulberry fibers have been used as fibrous raw materials for manufacturing traditional handmade paper, hanji for a long time. Compared to wood pulp fibers, pulp fibers from mulberry bast tissue have some benefits in physical and chemical properties due to their high D.P (degree of polymerization), M.W (molecule weight) and long fiber length. Specially, Korean handmade hanji shows outstanding characteristics in mechanical tensile strength, folding endurance, flexibility and long sustainable conservation properties. Therefore, hanji is widely applied to daily supplies, hygienic goods, medical supplies, clothing industries and so on. Recently, the potential demand of mulberry pulp fibers is more and more increased on the strength of high application fields. This study was focused on the possibility of wastewater recycling in unit operation systems for the development of automated mass production line. The properties and environmental loads of wastewater from debarking, cooking, bleaching and screening process were analyzed by means of COD, conductivity, turbidity and solid materials. The wastewater from debarking and cooking process was comparatively high in pollution load, and would be treated by additional approaches of chemico-physical method.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Proceedings of Pre-symposium of the 10th ISWPC
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• pp.186-191
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• 1999

Results are shown on the preparation and characterization of homopolymer of 2-methacryloyloxyethyl isocyanate(MOI) ad copolymers of MOI with styrene synthesized by radical polymerization. The significant effectiveness of the polymers as additives for paper dry and wet strength was found. Dry strength can be increased by 75% and wet strength retention of sheets can reach 30% based on the increased dry strength and about 50% based on the dry strength of untreated sheet. Based on isocyanate group consumption, copolymers containing less isocyanate can give better effect than homopolymer in sheet wet strength improvement. Furthermore, the base paper containing a small amount of polyallylamine hydrochloride was used for polymer treatment and got higher wet strength improvement.

• 펄프종이기술
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• 제35권1호
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• pp.1-6
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• 2003

This study was carried out to investigate the effect of internal fibrillation on the pulp and paper properties. The internal fibrillation was introduced into the SwBKP and recycled SwBKP by the mechanical treatment with Hobart mixer. WRV and physical properties of SwBKP were improved by the internal fibrillation. However the mechanical treatment of recycled SwBKP resulted in the decrease of strength properties of paper except for the tear index, although it was observed that WRV was somewhat increased by the mechanical treatment. The decrease of strength properties of recycled SwBKP might be caused by the hornification of fiber and the decrease of fiber strength.

• 펄프종이기술
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• 제31권1호
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• pp.10-16
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• 1999

Air froth flotation was applied to OCC recycling process as a new pulp fractionation method and the effects of strength and drainage properties of testliner were also investigated. Fines including inks, stickies, and inorganic substances in OCC stock furnish were efficiently separated by the flotation. After the flotation, selective enzymatic treatment on the flotation reject was separately preformed, and then, the refined long fiber(flotation accept) portion was combined again with the fines(flotation reject) fraction for papermaking. This combination process was found to be effective in improving strength and drainage properties of testliner based on 100% OCC.