• 공업화학
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• 제9권4호
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• pp.529-535
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• 1998

탈묵공정에서 고지 배합처리, 온도, 양품 배합처리 등의 해리 공정조건 변동에 의한 탈묵펄프의 영향을 조사하였다. 실험계획법으로써 탈묵펄프에 주된 영향을 미치는 유의한 인자를 선정하였으며, 통계분석기법 중 하나인 분산분석 및 다중비교를 통해 공정조건의 최적수준조합을 결정하고 이에 따른 백색도 및 강도적 특성의 추정치 및 신뢰구간을 구하였다. 백색도는 $Na_2SiO_3$ 2.0%, $H_2O_2$ 0.5%, 고지 배합처리 (국내신문고지 : 수입신문고지 : 매거진 = 40 : 30 : 30 wt %)의 조건에서 가장 높은 추정치 50.5%와 90% 신뢰구간 (49.0, 52.0)을 얻을 수 있었다. 인장지수는 $H_2O_2$ 0.5%, 해리 온도 $50^{\circ}C$의 조건에서 가장 높은 추정치 $35.7N{\cdot}m/g$과 90% 신뢰구간 (34.6, 36.6)을 얻을 수 있었다. 파열지수는 계면활성제 0.1%, 해리 온도 $50^{\circ}C$의 조건에서 가장 높은 추정치 $0.129kPa{\cdot}m^2/g$과 90% 신뢰구간 (0.125, 0.133)을 얻을 수 있었다.

• 펄프종이기술
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• 제33권2호
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• pp.8-16
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• 2001

To manufacture toilet tissue with ONP (old newspaper), the effect of fractionation fiber (R150, R100, R70 mesh) and bleaching(P, PY), blending (70/30) with MOW(mixed office wastepaper) or WL(white ledger) and the addition of softener on the optical and mechanical properties were studied. Considering the pulp yield, brightness and strengths, fibers of R100 mesh fraction were proper to be produced to toilet paper from ONP. This pulp showed the pulp yield of 76.8%, brightness of 50.2% ISO and tensile index of 21.1 Nm/g. By the bleach with P and PY stages, the brightness of the pulps increased up to 60.3% ISO and 61.8% ISO, respectively. When blended with MOW (57.3% ISO) or WL (76.2% ISO), the brightness of the former increased up to 58.5% ISO, the latter up to 63.6% ISO. The strengths of pulp blended with WL were higher than those of fractionated pulp from 100% ONP, however there was no difference in strengths between fractionated pulp and blended pulp wth MOW. While the addition of softener improved the softness of paper, but it decreased strengths of pulp and extended dispersing time in water.

• 펄프종이기술
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• 제33권2호
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• pp.24-31
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• 2001

As a novel method to improve strength properties of recycled test liner, Condebelt press drying system was introduced and adopted into Korea. New press drying treatment could enhance the surface and strength properties in accordance with the increase of sheet density. However, Condebelt drying can not increase the density of repeatedly recycled test liner as much as that of virgin UKP and at the same density condition, the strength of Condebelt press dried UKP is greater than that of press dried test liner. In order to increase the strength of test liner, two attempts were tried in this study. First, addition of polyelectrolytes, dry strength agent was investigated with a view to promote the fiber bonding potential of reclaimed corrugated container pulp. Second, blending effect of fines were analyzed in an aims of increasing density and strength of test liner. The results were as follows; Even in the case of test liner densified by Condebelt press dryer, addition of amphoteric PAM as a dry strength agent was effective in increasing strength properties and so the effect of dry strength agent on improving bonding potential of recycled OCC fiber could be confirmed. As an appropriate addition level of amphoteric PAM, below 1% based on dry pulp weight was suggested. Different from virgin UKP, density of recycled test liner can be increased by the blending of OCC fines and strength properties also can be improved. However, excessive blending of OCC fines could result in decreasing of density and serious weakening of test liner. The best blending ration of fines in test liner can be determined as about 30%. Taking into account the fines content in general OCC pulp as 50%, excessive 20% of fines were supposed to be fractionated and removed in order to achieve the best strength of Condebelt press dried test liner.