• 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.

• 한국포장학회지
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• 제11권1호
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• pp.33-40
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• 2005

This study was carried out for effective utilization of recycling resources to investigate the repulping conditions of car air filter waste paper and to evaluate the application into corrugating medium papermaking by blending these repulped pulps. Car air filter waste paper was made of virgin BKP and it was dipped into phenol resin solution. It was well disintegrated by laboratory Valley beater with 10%(basis on oven-dried pulp weight) NaOH addition and defoamer usage. The optimal temperature, beating consistency and treatment time were mainly $40^{\circ}C$, 1% and $30{\sim}40$ minutes, respectively. Handsheets were prepared with various blending ratios between air filter recycled pulp and KOCC. In the case of $10{\sim}20%$ substitution with air filter recycled pulp, physical properties reductions as compressive strength and burst strength of sheets were lower than others. These results showed more favour than the partial substitution of KOCC for corrugating medium even though some strength reduction of paper. It was also observed that the waste water of air filter recycling was not affective to environmental problems.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.181-190
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• 2006

This study was conducted to develop dry forming technology and evaluate the properties of dry formed paper made from Hw-BKP. A dry forming mold (DFM) was developed to observe the phenomena of dry forming and evaluate the properties of formed papers. To upgrade the DFM a dry forming system (DFS) was developed. This DFS was designed to improve the formation of dry formed papers and enhance the productivity of dry forming. Dry forming gave papers with greater bulk and opacity than wet forming. Tensile strength of dry formed paper was greater than that of conventional wet formed handsheet when they were made from the same dry disintegrated fibers. But tensile strength of conventional wet formed handsheet made from beaten fiber was much greater than that of dry formed paper made from dry disintegrated fibers. When solvent dried beaten fibers were used in dry forming, the tensile strength of dry formed papers reached 73.5% of the wet formed handsheets made from beaten fiber. It showed that dry forming has a significant potential in improving strength properties when proper preparation of fibers and appropriate humidification, pressing, and drying processes are employed.

• 펄프종이기술
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• 제46권3호
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• pp.50-57
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• 2014

In this study, we investigated the physical properties of kraft pulps made from rice husk, peanut husk and garlic stems. These agricultural byproducts were collected individually, and then various pulps were manufactured from them by controlling active alkali, sulfidity, reaction time and the liquor ratio in the kraft pulping process in order to analyze the applicability of these agricultural byproducts as raw materials for kraft pulps. After kraft pulping, we measured yield, flake content, fiber length, fiber width and freeness of pulps, and the fiber shapes of the pulps were observed by using an optical microscope. When the higher active alkali, longer reaction time and lower liquor ratio were applied in kraft pulping process, reject content decreased and fiber yield increased. The pulp from garlic stems had the longest fiber length and that from rice husk showed the highest intial freeness. All of the pulps from agricultural byproducts showed higher initial freeness, shorter fiber length and the similar fiber width compared to OCC, BCTMP and hardwood BKP. The fibers of the pulps made from agricultural byproducts showed a similar shape to those of commercial pulps. It was concluded that these agricultural byproducts had a potential as raw materials to produce an alternative pulp to the commercial pulps.

• 펄프종이기술
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• 제46권6호
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• pp.71-77
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• 2014

Despite the ubiquity of electronic media, paper is still the most generally readable carrier of information. Because paper materials are deteriorated by chemical, biological and physical factors over time, there have been major concerns about the decay of large collections of books, publications, old maps, historical artifacts, and written records. Therefore, manufacture of permanent paper has been a highly debated issue in paper conservation research. Through the use of permanent paper, our new records, journals, library books, art works, and all culturally and historically important documents can be preserved. In this study, handsheets were made of mixture of hemp bast fiber produced by soda pulping and HwBKP varying the amount of hemp. Physical, mechanical and optical properties of each handsheet were examined. As the ratio of hemp bast fiber increased, mechanical properties were improved significantly, but opacity decreased. After aging, the optical properties of the handsheets mixed with the hemp bast fiber more decreased than those of the non-mixed handsheet. The more mixture ratio of hemp bast fiber increased, the more decreasing rate of optical properties increased. As a result, it was confirmed that hemp bast fiber is a very promising resource for the manufacturing of permanent paper.

• 펄프종이기술
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• 제39권1호
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• pp.16-24
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• 2007

This study was performed to investigate the reaction between alkylketene dimer(AKD) and cellulose molecules in AKD-sized paper sheet. AKD was added to highly beaten($80{\pm}3^{\circ}SR$) SwBKP(ca. 0.8% on pulp) in order to have much AKD retention in the paper sheet. This AKD-sized paper sheet was aged at different temperatures, $60^{\circ}C,\;80^{\circ}C,\;105^{\circ}C\;and\;125^{\circ}C$. Changes in FT-IR spectra of AKD in paper sheet during the ageing were measured. In addition, sizing degrees of the AKD-sized paper sheet pretreated for 30 sec. at $105^{\circ}C$ were measured by HST size tester during the storage at different temperature. IR spectra of AKD-sized paper sheet preheated at $105^{\circ}C$ for 30 sec. showed unchanged spectra two absorption bands at $1849cm^{-1}\;and\;1722cm^{-1}$ which refer to the typical AKD IR bands. However, these typical AKD bands were gradually reduced with increasing ageing, completely disappeared after 6 hrs. and formed new absorption band at $1706cm^{-1}$, which refers to carbonyl stretching vibration of dialkylktone. Eventually the AKD molecule was hydrolyzed to diakylketone without formation of ${\beta}$-ketoester with cellulose in paper sheet. After 6 days ageing, a little amount of ${\beta}$-ketoester bands was identified in 6 or 7 days ageing, because of the absence of water due to long-term heating. The same tendency was observed at different ageing conditions. At the practical papermaking process, AKD reacts prevailing with water, and mostly seems to be hydrolyzed to dialkylketene. Concerned to the sizing development, AKD-sized paper sheet was shown no sizing development at the initial stage of ageing at $60^{\circ}C$ after heating treatment at $105^{\circ}C$ for 30 sec., and gradually increased the sizing degree with increasing ageing, such as Hercules Sizing Tester (HST) 130 see for 12 hr, HST 300 sec. for 3 days and HST 400 sec. for 5 days. It was concluded that hydrolyzed AKD could contributed to the sizing development of the paper sheet.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2000년도 춘계학술발표논문집
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• pp.48-48
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• 2000

효율적인 wet-end시스템의 적용으로 중성 초지시스템의 이점을 최대한 구현하고 이에 따른 초지계의 안정성 및 원가절감 등을 얻기 위해서는 중성 초지 시스템에서 사용되는 사 이즈제 및 사이징 공정에 대한 연구가 매우 중요하다. 현재 중성 사이즈제로는 AKD와 A ASA가 가장 널리 사용되고 있는데, 유럽에서는 주로 AKD가 쓰이고 있으며, 미국에서는 A ASA가 50%정도 사용되고 있다 .. AKD에 비해서 ASA는 사이즈도의 발현이 매우 빨라 사이 즈 프레스에서 사이즈도가 발현되므로 사이즈 프레스에서의 픽엽 조절 및 지절감소에 유리 한 장점을 가지고 있다. 하지만 ASA는 AKD에 비해 반웅성 높아 습부에서의 가수분해되어 초지 조업성을 악화시키는 문제점을 지니고 있다. 이러한 문제를 극복하기 위해서는 ASA 유화액의 정착성을 개선시키기 위한 연구가 시급히 요청되고 있으며 여기에는 ASA의 유화 에 사용되는 양성전분의 최적화가 가장 핵심적인 기술로 평가된다. 현재 ASA용 유화제로는 양성전분이 가장 많이 사용되고 있다. ASA 에멀션 제조에 있 어서 양성전분의 역할은 음전하를 가지고 있는 ASA 입자에 홉착되여 양전하를 부여함으로 써 콜로이드 업자의 안정성을 부여할 뿐만 아니라 섬유와의 정전기적 인력을 유도하여 정착 을 증진시키는 효과를 나타낸다. ASA 유화용으로 쓰이는 양성전분 중에서는 감자전분이 가 장 효과적인 것으로 알려져 있으며 옥수수나 타피오카 둥도 쓰이고 있다. 그러나 국내의 경 우 감자전분은 옥수수전분보다 가격이 비싸다는 단점이 있으므로 저렴한 옥수수 전분을 이 용하여 ASA 유화용 변성전분의 개발이 국내 제지산업의 경쟁력 강화를 위해 시급히 요망 되고 있다. 본 연구의 목표는 옥수수 전분을 이용한 ASA용 유화안정제를 개발하고 그 효과를 극대 화시킬 수 있는 적용기술을 확립하는데 있다. 옥수수전분을 이용한 ASA 유화용 변성전분은 외국에서 소개된 바가 있기는 하지만 사이즈도 발현이 감자전분의 절반 수준으로 효과적이 지 못한 것이 문제점으로 지적된 바 있다. A ASA 유화용 전분으로는 감자전분과 옥수수전분으로 제조된 외국산 기존 제품과 본 연 구를 통해 개발된 옥수수 전분을 이용하였다. 먼저 실험실적으로 최적의 ASA 에멸션의 유 화가 가능하도록 유화조건을 설정하여 유화액의 입도가 1µm 정도가 되도록 하였다. 이들 A ASA 사이즈제를 Hw. Sw-BKP로 조성된 지료에 투입하여 수초한 후 Hercules 사이즈도 측정기를 이용하여 수초지의 사이즈도를 측정하였다. 또 사이정 효과를 극대화시키기 위한 방안을 모색하기 위해 ASA 에말션의 입도, 제타전위, 탁도 등의 평가를 병행 실시하였다. 실험 결과 기존의 방법으로 유화한 경우 수입감자양성전분이 가장 높은 사이즈도를 보였 다. 그러나, 적절한 전분변성법과 유화조건을 개선함으로써 옥수수전분을 이용하여 수입 감 자전분이나 수입 옥수수전분보다 더 우수한 ASA 사이정 효과를 나타내는 양성전분이 개발 될 수 있음을 확인하였다.