• Journal of Forest and Environmental Science
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• v.8 no.1
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• pp.67-76
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• 1992

The effects of HwBCTMP on the characteristics of paper were compared with those of HwBKP. The fiber fraction below 0.1 mm of HwBCTMP was higher than those of HwBKP. HwBCTMP was superior to the HwBKP in the improvement of opacity, apparent density and smoothness, and in the decrease of air permeability. The strength properties and stiffness obtained with the addition of HwBCTMP were better than those of HwBKP. Therefore, HwBCTMP might not only be well substituted for HwBKP but also decrease production cost and improve paper properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.41-48
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• 1999

This study was intended to investigated the effect of pulp type and intital calendering on the properties of recycled fiber. As the number of recycling is increased, at least by the fourth recycling , the freeness of the SW-BKP and HW-BKP increased. And then that decrease after the fifth recycling. Especially the freeness of CTMP increased more rapidly than any other pulp in first recycling. And there was no difference of freeness in all kind of pulp by initial calendering . The speed of dewatering in making sheet consistetly became slow by proceeding recycling on condition of all calendering. and the order of the speed of dewatering was as followed. CTMP>HW-BKP>SW-BKP. However in case of HW-BKP, which was low -yield pulp, the tendency of the speed of dewatering was similar to that of CTMP which was high-yield pulp and had high content lignin . There was no change of fiber length and no effect of calendering by recycling of HW-BKP and CTMP. Howeverfiber length of SW-BKP generally decreased, especially in calendering of high temperature and high pressure conditions. The WRV of SW-BKP diminished by proceeding recycling but that of HW-BKP and CTMP diminished in the first recycling and then there was no change of the WRV of HW-BKP and CTMP. The contents of fines of HW-BKP consistently decreased by the fourth recycling and then increased in the fifth recycling . On the other hand there was no tendency in the content of fines of SW-BKP and CTMP by the number of recycling.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.7-12
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• 2009

The effects of refining either SwBKP or HwBKP, and both of SwBKP and HwBKP on the physical properties of paper were investigated in order to elucidate if the non-conventional refining and blending method can be used for the optimizing the paper properties. The blending ratio of SwBKP and HwBKP was 15:85. The highest bulk was obtained with the refining of SwBKP only. Any differences of opacity were not observed in unfilled paper, while the highest opacity of PCC filled paper was obtained at same bulk when the only HwBKP was refined. However burst index and tensile index did not showed any differences in the relationship with bulk. Therefore this result can be applied to improve the opacity of paper without sacrificing of strength properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.4 s.117
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• pp.10-16
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• 2006

The study was carried out to investigate how the refining of pulps affects the stress-strain characteristics and physical properties of paper. SwBKP and HwBKP were refined with Hollender laboratory beater to obtain three levels of freeness(500, 400 and 300 ml CSF) at the different consistencies(0.5% and 1.0%). The effects of fines were also evaluated. The stresses and strains of papers made from SwBKP and HwBKP were increased with refining. The absolute value of strain in paper made from SwBKP was higher than those of paper made from HwBKP. We also found that the presence of fines increased the stress and strain significantly in both pulp types. The refining at lower pulp consistency gave higher stress and strain properties. Most physical properties of paper were improved with refining, but the effect of refining consistency depended on the characteristics of each physical properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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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 Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.60-65
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• 2015

In order to improve the strength of paper, mixing ratio of Sw-BKP and Hw-BKP and PVA (polyvinyl alcohol) fibers dosage were investigated. When the Sw-BKP fraction was increased, strength properties were increased because of average fibers length increased. When PVA fraction increased, paper strength was increased, but there was dissolution of PVA in water. The reason for improving handsheet strength that contained PVA was due to increased bonding action between the fibers by the PVA. The addition of PVA to kraft pulp would be helpful for packaging paper materials to increase strength and fracture toughness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.3
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• pp.39-47
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• 2000

This study was carried out to investigate the effect of the type of base papers containing Sw-BDP, HW-BDP and Bamboo-BKP on the properties and printabilities of coated papers. Also it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of Bamboo-BKP was observed longer than that of the Hw-BKP and shorter than that of the Sw-BKP. This has effect on physical properties. Therfore the results of mea-suring physical properties were higher ratio of Sw-BKP physical properties tended to be slightly higher with the increase I the mixing ratio. Considering the optical properties of base papers the highest opacity was obtained in case of the Hw-BKP and the second appeared Bamboo-BKP. On the other hand smoothness roughness and air permeability of Bamboo-BKP were lower than those of wood pulp and the optical properties of coated papers tended to show the similar with those of base papers. The ink receptivity and print gloss of the coated papers for Bamboo-BKP were lower than those of wood pulp. As the mixing ratio of Sw-BKP was increased the properties and printabilities were improved slightly. Meanwhile amphoteric latex was improved the optical properties and printability of coated papers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.3
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• pp.81-87
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• 2014

Conditions of paper manufacturing process should be changed depending on the end use and paper properties. Most of the case, mixed pulps with long softwood fibers and short hardwood fibers are used to achieve proper qualities of product with reasonable production cost. For specialty paper manufacture the wood pulp and cotton linter pulp are usually mixed together. The objectives of this study is to analyze physical, mechanical and fracture mechanical properties of paper depending on SwBKP, HwBKP and cotton linter pulp(CLP) mixing. When the mixing ratio of SwBKP was increased, strength properties, such as tensile, tear, and folding endurance, were also increased. When the mixing ratio of SwBKP and HwBKP was increased, stress concentration index was decreased and fracture toughness was increased.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.8-15
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• 2000

This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, SW-BKP, White ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strehgth properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and White ledger no increase except tear index. In Hobart mixer pre-treatment, HW-BKP and White ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and White ledger were 0.837 mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mm and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.70-70
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• 2000

This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, Sw-BKP, white ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strength properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and white ledger no Increase except tear index. In Hobart mixer pre-treatment, HW-BKP and white ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and white ledger were 0.837mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mn and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.