• 펄프종이기술
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• 제47권1호
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• pp.93-101
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• 2015

The purpose of this study is to examine the reusability of the fluff pulp recycled from paper diaper. To do this, the physical and optical properties of each handsheet made from these fluff pulp sample as well as the properties of the fiber recycled from paper diaper were analyzed and compared with those of non-recycled diaper fluff pulp samples and conventional pulp samples. These comparisons show that the characteristics of fiber such as length, width, curl, kink of the pulp recycled from paper diaper were similar to those of non-recycled diaper fluff pulp as well as to those of commercial pulp. The fine content of recycled diaper fluff pulp was lower than that of other pulp samples, while the ash content of the former was higher than that of the latter. Furthermore, it was also found that the bulk of handsheets made from the recycled fluff pulp was higher than that of other pulp samples, while the formation of the former was worse than that of the latter. The mechanical properties of the handsheet sample made from the recycled diaper fluff pulp was higher than those of the unused diaper fluff pulp and was lower that those of commercial fluff pulp and softwood tissue pulp handsheet. But, it was higher than that of hardwood tissue pulp handsheet. The optical properties of recycled diaper fluff pulp handsheet was lower than those of each handsheet samples made from other pulps due to its low fine content.

• Journal of the Korean Wood Science and Technology
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• 제48권5호
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• pp.581-590
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• 2020

Pulp refining is the major way to alter the properties of fibers and formed paper. Different combinations of the bar profile of the rotor and stator during low consistency refining processes directly affect the properties of the paper. In this study, a mixture of softwood and hardwood pulp was refined by varying the bar angle of the stator while that of the rotor is fixed at 0º. The pulp samples were collected at different refining times. Then, the pulp and paper properties, such as beating degree, fiber external fibrillation, and tensile and tear indexes were measured to explore the effects of the combined refining plates at different bar angles on paper properties. The results of the experiment show that the combined refining plate of 0º and 5º recorded the most significant improvement in the pulp beating degree and fiber external fibrillation. This consequently increased the fiber bonding area, which in turn, improved both the tensile and the tear indexes of the paper. Also, the influence of the combined refining plates with a larger bar angle on the paper properties was weaker compared to that of smaller angles. This study not only provides ideas for the bar profile design but also improves the optimal selection of refining plates.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2003년도 추계학술발표논문집
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• pp.139-147
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• 2003

Coater runnability of the paper coating and final product properties can be affected by the immobilization of coating color and the dewatering into the base paper. During the dewatering, the rheological properties and solids content of a coating are dramatically changed. For the purpose of obtaining better coater runnability and high quality of coater paper many papermakers are trying to improve the water retention of paper coatings by using some additives such as thickener and co-binder. In this study, we tried to investigate the rheological properties and the immobilization point of coatings with immobilization cell during the dewatering of coatings.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Pre-symposium of the 10th ISWPC Recent Advances in Paper Science and Technology
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• pp.227-231
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• 1999

Condebelt drying provides opportunities not only of improving the strength properties and saving of drying energy but also of reducing the basis weight or increasing the utilization of recycled furnishes. In this paper general overview of the Condebelt press drying will be described and the effects of the process variables in Condebelt press drying including drying temperature, pressure, drying time and moisture content of the sheets on the paper properties is discussed. The experiment was performed with a static rig and Korean OCC was used as a principal raw material. Significant improvement in sheet density, compression strength, tensile strength, surface smoothness, etc. was obtained when Condebelt drying was applied. Control of pressure and inlet dryness was found to be very critical in improving sheet properties. Mill experiences from Dong Il Paper Mfg. Co., Ltd is briefly described.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.445-450
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• 2006

The stress and strain properties of KOCC were modified to improve the performance of KOCC as a packaging raw material. The refining consistency, refining degree and the grammage of handsheet were varied. The stress strain properties, tensile energy absorption were measured for prepared handsheets. The refining improved significantly the stress and strain properties of paper, especially at lower refining consistency. The increase of grammage also had contributed to improve the stress and strain of paper. It was also found that both refining and grammage contributed to the improvement of tensile energy absorption. However, it is strongly recommended to introduce the combination of refining consistency, refining degree and mechanical treatment.

• 펄프종이기술
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• 제42권2호
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• pp.61-66
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• 2010

Corn stalk, one of the most abundant agricultural residue in the world, was examined in this study to use it as an alternative fiber source of wood fiber. In order to find the proper way to utilize corn stalk more efficiently, the morphological properties and the papermaking properties of the, bast fibers and the corn pith, were evaluated respectively. Although the bast fiber fraction showed comparable properties to those for hardwoods in the fiber properties and the papermaking properties, the pith resulted in low brightness and low drainage rate. But the short and flexible fibers in pith fraction led to dense and compact handsheet structure, correspondingly the higher sheet strength. There big differences in properties between bast fiber and pith should be considered for the fully utilization of corn stalk.

• 펄프종이기술
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• 제36권4호
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• pp.9-15
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• 2004

To increase paper strength, refining and wet pressing are performed. Many researches were carried out to identify the origin of paper strength. Since fracture toughness was governed by stress concentration, fracture toughness reflects microscopic paper strength. The aim of this paper is to analyze how paper strength was affected by changes of refining and wet-pressing. Fiber properties and structural, tensile and fracture properties of hand­sheets were evaluated. Especially, fracture toughness was evaluated by J-integral. As the refining proceeds, stock properties maybe divided into two stages such as fibers activation and fines activation according to freeness. In fibers activation stages, about 750-450 mL CSF, the fracture toughness increased with refining and wet pressing but in fines activation stages, about 450-250 mL CSF, the fracture toughness increased only with wet pressing. It is clear that fracture toughness was affected not only by fibers properties but also by fines properties in fines activation stages.

• 펄프종이기술
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• 제48권3호
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• pp.80-90
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• 2016

The purpose of this study was to investigate the functional properties of natural dyed Hanji for cultural properties conservation and storage. To estimate functional properties of Hanji, antimicrobial, insect repellent test, and Oddy test were executed. Hanji dyed with 10% Golden thread (Coptis chinensis), a natural dye and silver nitrate mordanting showed the most excellent antifungal activities against A. niger, P. chrysogenum, and Trichoderma sp. before and after aging. The insects repellent test followed didn't indicate significant effects on treated Hanji against Lasioderma serricorne, Sitophilus zeamais, and Tribolium castaneum. According to Oddy test result, Hanji dyed with Golden thread and silver nitrate caused no significant corrosions on copper, silver, and lead after aging 28 days.

• 펄프종이기술
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• 제45권3호
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• pp.52-58
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• 2013

To evaluate the anisotropic characteristics of Korean traditional paper-Hanji, the physical and mechanical characteristics of hand-made hanji, and machine-made hanji were investigated in this research. The densities of copying paper and newsprint paper appeared to be two times higher than the densities of hand-made hanji using Ssangbal sheet forming and hanji made of paper mulberry fiber. The breaking length, and tear index of both Hanji using Owangbal sheet forming, and hand-made Hanji using Ssangbal sheet forming appeared to be different according to the directions in paper. The breaking lengths of Hanji using Owangbal sheet forming showed little differences according to the directions. Breaking length of Hanji using Ssangbal sheet were slightly higher than those of Hanji using Owangbla sheet forming. The breaking lengths of machine-made hanji, copying paper, and newsprint paper were two to four times higher than those of hand-made Hanji. The breaking length showed higher differences according to the direction than the tear index. The tensile strength according to the directions in paper showed significant differences (${\alpha}$=0.05) in all papers used in this research.

• 펄프종이기술
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• 제35권3호
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• pp.21-28
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• 2003

It is essential to use base papers having proper surface characteristics in coating operation for improving coated paper quality and coater runnability. To fulfill these purposes surface sizing of coating base stock with anionic oxidized starch is commonly practiced. It is suggested that use of cationic starch for surface sizing rather than conventional oxidized starch will improve coated paper quality since cationic starch penetrates less into paper structure because of its strong electrostatic interaction with anionically charged paper surface. Strong interaction of cationic surface sizing starch with anionic coating color is expected to promote rapid immobilization of the coating color and improve coating holdout and optical property. The immediate objective of this study was to examine the influence of surface sizing starches on the properties of coated papers. Structural characteristics of the coatings formed on the substrate surface sized with cationic and anionic starches were examined. To enhance the efficiency of cationic surface sizing starch on coated paper properties, strongly charged cationic polymers were added to the surface sizing starch and its effect on coated paper properties was evaluated. Results showed that opacity and light scattering coefficient of coated paper were higher when base paper surface sized with cationic starch was used. Addition of less than 1% of cationic poly-DADMAC to the cationic surface sizing starch improved the opacity of coated paper significantly.