• 펄프종이기술
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• 제40권3호
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• pp.15-22
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• 2008

Properties of pulp fibers can be modified by LbL multilayering technology. We evaluated the effect of stock composition on the polyelectrolyte multilayering performance of pulp fibers in this study. Stock composition was varied with pulp type and fines content. Three types of pulp-Hw-BKP, BCTMP and KOCC-were treated with polyelectrolytes of poly-DADMAC and PSS. Fines content of stock were controlled at 0, 10, 20, 30, and 40%. Zeta potential of pulp fibers and charge demand of filtrate were evaluated. The highest adsorption ratio was obtained for BCTMP because of its shortest fiber length and highest specific surface area. Higher fines content in the stock increased the adsorption ratio of polyelectrolyte onto pulp fiber and it required a higher amount of polyelectrolyte for charge neutralization. For the pulp stock with higher fines content, a higher level of polyelectrolyte and the increased layer number were required to modify and stabilize the electrochemical properties of pulp fibers.

• 펄프종이기술
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• 제31권2호
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• pp.86-91
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• 1999

A new test method has been developed for a quantitative evaluation of macro-stickies in recycled pulps. The method uses a fine slot screen to separate a sticky particles form fiber in the pulp samples. The obtained sticky particles were spread on filter paper and covered with silicon carbide powder in order to make the stickies area with sufficient contrast between stickies and background. The stickies are then counted by a scanner-based image analysis system. The validity of this evaluation method of stickies of KOCC, ONP and white ledger wastepaper recycling plants respectively. It is shown that this method can be applied for a quantitative determination of stickies content in various recycled pulp samples. With this testing method, reproducible and reliable data were obtained for the actual mill pulp samples.

• 펄프종이기술
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• 제43권5호
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• pp.17-26
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• 2011

Drying behavior and physical properties of HwBKP, SwBKP, and OCC handsheets depending on kneading, refining and wet pressing were analyzed. The maximum drying shrinkage velocity was newly adopted to verify the effect of mechanical treatment of pulps by evaluating drying behavior according to varying the kneading, refining and wet pressing treatments. Those various treatments were changed to evaluate the relationship between the maximum drying shrinkage velocity and handsheets properties. When the drying shrinkage and the maximum drying velocity increased by refining and wet-pressing, handsheets strength was increased. The maximum drying shrinkage velocity showed higher correlation with physical properties of paper than WRV at different refining loads at SwBKP and mixed pulp. At high wet-web dryness, drying shrinkage, the maximum drying shrinkage velocity and strength properties of handsheet were increased. It meant that drying shrinkage behavior was highly affected by not only fibers' shrinkage but also fiber bonding. Kneading pre-treatment for KOCC and SwBKP effectively modified fiber properties and increasing paper strength and drying shrinkage. The effect of kneading pre-treatment was also confirmed by the maximum drying shrinkage velocity. Strength properties of mixed pulp handsheets were not increased by the kneading pre-treatment, although the maximum drying shrinkage velocity and WRV was increased. It meant that fibers network bonding of HwBKP was limited because of ves sels and ray cells' interference for bonding. Therefore in order to improve paper strengths containing HwBKP by mechanical treatments, interference of vessels and ray cells for fiber bondings should be carefully controlled.

• Journal of the Korean Wood Science and Technology
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• 제33권3호통권131호
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• pp.79-88
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• 2005

연구는 폐표고목을 제지용 원료로 활용하기 위한 기초자료로 1년부터 5년 동안 재배한 표고골목을 이용하여 목재 성분 조성과 크라프트 펄프화 특성을 평가하였다. 그 결과 화학조성의 경우 변재에서는 재배기간이 증가함에 따라 글루코스와 자일로스의 감소가 크게 나타났으나 심재부에서는 큰 차이가 나타나지 않았으며 정선수율과 리젝트 함량 모두 재배기간이 증가함에 따라 감소하였다. 펄프 특성에서도 재배기간 증가에 따라 섬유장과 폭, 여수도는 감소하였으며 폐표고골목 크라프트 펄프를 국산 폐골판지에 첨가 시 종이의 건조 강도가 향상되었다. 이상의 결과로 폐표고목 크라프트 펄프를 다른 장섬유 펄프와 혼합사용 시 강도 향상과 고해 에너지 감소를 기대할 수 있을 것으로 사료된다.

• 펄프종이기술
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• 제42권2호
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• pp.95-101
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• 2010

For the development of higher-sizing performance of paper, a sizing agent using recycled PET was synthesised. Polyester resin was extracted from wasted PET by subcritical hydrolysis and finally modified to synthetic sizing agent by mixing water-disperse PET with triphenyl phosphite(TPP). The modified PET was considered as an internal sizing agent in different wet-end papermaking conditions. The optimum condition in sizing efficiency was obtained in initial pH of 6.5 in case of rosin+alum system, and 7.5 in case of rosin+alum+PET system, respectively, and in addition amount of PET 3%. The sizing efficiency was also closely related according to the fiber properties of wet-end slurry, such as virgin fibres from UKP and recycled fibres from KOCC. The application of modified PET was good in strength improvement of paper, specially in tensile strength.