• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.5
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• pp.26-31
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• 2007

Hanji is a traditional Korean handmade paper, which has been known in ancient Far East as excellent quality calligraphic paper for more than 1,500 year. Hanji is mostly made of Korean paper mulberry bast fibers, and if properly processed, normally lasts for more than 1,000 years with significant strength and still recognizable calligraphic writings or drawings on it. Dochim is a special way of Hanji calendering process, but is turned out to be quite different from modern calendering (machine calendering) in several aspects. In Dochim process, mechanical impacts were applied vertically to the surface of papers. Compared to the modern calendering, Dochim increased paper gloss much more, but paper smoothness a little less. By the Dochim process, densification occurred and the degree of densification was more sensitive to the fiber type in the Dochim process than in the calendering method.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.2
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• pp.73-79
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• 2008

The permanence is of great importance to library and archival paper. According to the established standardizations including ISO and ANSI, the permanence can be specified with tear strength, pH, alkali reserve and kappa number. In this study, we evaluated the permanence and durability of domestic coated and copy paper grades. Two types of coated paper grades and all kinds of copy papers which were tested in this study were satisfied with the criterion of permanence specification. However, all of the tested paper grades didn't meet the requirements of durability because of their low folding endurance.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.423-426
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• 2006

Paper has fibers and fines network structure and it is strongly affected by interface bonding between fibers. Depending on the inter-fiber bonding, paper bulk is determined. Fines play an important roll in Campbell and consolidation effect through wet pressing and drying operations. Refined Sw-BKP, Hw-BKP and BCTMP fines were used to investigate the fines effect. Wet-web strength, breaking length, scattering coefficient, and hydrodynamic specific volume were measured. According to the result of experiments, chemical and morphological compositions of fines do not strongly affect to wet-web forming, but strongly affect to drying operations which form hydrogen bonding among fiber-fines-fiber matrixes. Paper bulk should be controlled by the extent of hydrogen bonding between fibers during drying operations.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.66-72
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• 2011

The annals of Joseon Dynasty is one of UNESCO's Memory of the World Register. For the safety preservation of the waxed annals of Joseon Dynasty, the acidic and alkaline aging mechanism of beeswax and beeswaxed Hanji has been investigated. The weight loss of beeswaxed Hanji by the acidic aging was higher than those of alkaline beeswax. The acid value and relative intensity of carbonyl groups in beeswax were slowly increased with aging time. The strength of dewaxed Hanji was decreased with aging time. The significant changes of crystallinity of dewaxed Hanji by acidic and alkaline aging were not observed.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2005.11a
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• pp.115-126
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• 2005

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.3
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• pp.38-45
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• 2002

The effect of sequential oxidative-reductive bleaching on brightening of the MOWs is investigated. The improvement in brightnesses of MOWs is more effective in conventional PFAS bleaching than in P/T bleaching. There is no difference in the mechanical properties or the bleached pulps between PFAS and P/T sequences. Considering the brightness gains and bleaching chemicals cost, for the MOW A(Initial brightness: 68.3% ISO) containing 5％ ONP and 20% colored paper, the P/T bleaching is more economical than the PFAS bleaching. However for MOW B(initial brightness: 59.1％ ISO) containing 15% ONP and 35％ colored paper, there is no difference in the bleaching efficiency between PFAS and P/T bleaching.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.81-86
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• 2000

Hanji is a traditional handmade paper, which has been famous for its excellent qualities in strength, whiteness, gloss, and smooth feel in painting and writing in ancient Far East for many years. Nowadays, however, its old fame has declined and it has been used only in limited extent such as in traditional Korean brush painting and writing. In this study, 9 kinds of commercial handmade papers made in Korea, China, and Japan were collected and their printing and writing properties were evaluated by image analysis. Chinese handmade paper showed the best result in absorption area of China ink, the roundness and feathering of China ink blots, followed by Hanji. Abrasion coefficient of the Chineses papers was higher than that of the others, which was regarded to contribute to the difference in touch feeling of the writing brush on the papers. It was shown that absorption rate and blot area of China ink were increased by Dochim. Hanji which has recently been made by so called \"traditional method\" showed no quality difference from the modified Hanji.ied Hanji.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.43-49
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• 1999

Effectiveness of the microparticle retention systems in improving dramage, retention, formation has been recognized for many years (1, 2, 3, 4, 5). In this study the effectiveness of crosslinked cationic corn starches and silica-based microgels as components of Compozil system has been evaluated. It was shown that improvements in retention and strength could be achieved by employing crosslinked cationic corn starches especially at high conductivity. Silica-based microgels with better performance in retention and dramage than a commercial colloidal silica sol have been made through a reaction of sulfuric acid and sodium silicate solutions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.2 s.120
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• pp.54-59
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• 2007

Cereal, computer software, wine, small appliances, and fast foods are examples of products that have switched from folding carton to microflute corrugated paperboard. Microflute corrugated paperboards have their unique wonderful packaging characteristics that are driving forces for people to use more and more. Good strength property, excellent shock absorbing ability, and beautiful outer appearance of microflute corrugated paperboards go hand and hand with their environmental advantages. It is known that physical properties of microflute corrugated paperboards depend on not only properties of base paper but corrugator operating conditions. This study was carried out to investigate on the corrugator's optimum operating conditions for making micro flute corrugated paperboards. Lab-scaled micro flute corrugator was installed and run with systematic changes of operation conditions to investigate the effects of operation conditions on physical properties of micro flute corrugated paperboards.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.30-35
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• 2008

Mechanical properties of paper mulberry bast fiber handsheets were investigated to study the characteristics of bast fiber in terms of being suitable for modern paper making process. Tensile, tear and burst strength of handsheets made from bast fiber of paper mulberry were better than those of NBKP handsheets. Smoothness of bast fiber was higher but stiffness was lower than NBKP. Sizing performance of bast fiber were worse. 3D image analysis showed that handsheets of bast fiber had inferior formation and more pores comparing to NBKP.