• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.391-394
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• 2006

Studied that the relationship between the charge density of PAC and its alkalinity, as well as the influences of PAC in paper sizing. Study results showed that PAC with higher charge density brought higher sizing degree when the same amount of $Al_{2}O_{3}$ content was dosed. However, there was no direct relationship between PAC charge density and its alkalinity, and higher PAC alkalinity can't improve its charge density. It was also found that the admixture (PPAC) of polyamine and PAC had higher charge density than PAC. The effects of PPAC on DRS and RAKD sizing were better than PAC sizing, when dosage and other sizing condition were the same.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.39-46
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• 2000

In pulp and papermaking process, enzymatic treatment of pulp fibres has been a topic of increasing interest in last decade. Lots of patents, papers and research reports were published on the application of enzymes in the fields of enzymatic bleaching, deinking, slime control, pitch control, waste water treatment and fibre modification. Cellulase and hemicellulase are the principal enzymes used for the modification of fibre property. This study was carried out for determinating the behaviors of enzyme to pulp fibres. A commercial enzyme, Denimax BT which is consisted with cellulase and hemicellulase, was treated to the kraft pulp produced from domestic hardwood mixtures. Results were mainly concentrated on the behaviors of freeness, drainability and fines content of fibres, and physical properties of paper with enzyme treatment. The freeness levels and dewatering ability were developed, and the fines contents were decreased. The creation of fines were controlled by the method of pre-enzyme treatment prior to fibre beating. The mechanical strength of paper, like tensile, burst, tear strength and folding endurance, were remarkably improved by the pre-enzyme treatment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.6-11
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• 2003

Refining process is of critical importance unit process for papermaking that influences freeness as well as many mechanical and physical properties of paper. Refining is the process that requires extensive amount of electrical energy. Thus it is required to evaluate the refining process in terms of its influence on fiber and paper properties as well as its effect on energy consumption. In this study, to evaluate the efficiency of refining process the theory of inch contacts has been employed, and the influence of refining processes on fiber and paper properties has been determined and discussed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.4
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• pp.1-6
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• 2001

Today's paper industry tries to use greater amount of high yield pulp and recycled fiber and to close mill water system, which results in higher fines content and buildup of organic and inorganic contaminants in white water system. Researches are being focused to develop chemical additives that provide good retention and drainage in a closed papermaking system. A microparticle retention system consisted of cationic guar gum and anionic colloidal silica so has been developed to meet the requirements for improving machine speed and product quality. The objective of this investigation was to determine the effects of the degree of cationic guar gums, charge density and structure of anionic colloidal silica sols, and the degree of system closure on the performances of this microparticle retention system. Cationic guar gums and anionic colloidal silica sols with higher charge densities showed better retention performance. Particularly, wider maximum in retention was obtained when structure colloidal silica was used suggesting as mechanism of microparticle bridging is functioning in this system.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.41-48
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• 2015

Fiber identification was attempted for the early twenty century documents that were classified as national archives in Korea, as an initial step for establishing scientific preservation and restoration method. Fiber staining with C stain and a digital microscope were used for the observation. All the documents observed consisted of mostly softwood fibers from fir (Abies) and other minor supplementary fibers, and they were all deteriorated seriously by various damages and aging process. It seemed that at around 1914-1934, fir was used frequently as papermaking raw material.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.9-14
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• 2008

Agar-agar extracted from red algae was used as a surface sizing material for paper after filtering, bleaching, and viscosity adjustment by oxidative depolymerization. Oxidized starches from corn and tapioca were compared to agar-based surface size in the respects of paper surface modification, strength improvement, and printability. Agar-based surface size showed high strength improvement and good printability as much as starch-based ones except film forming ability, which may be improved by adding additives, and demonstrated its great potential to be used as inexpensive and high quality surface size in future.

• Fibers and Polymers
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• v.6 no.2
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• pp.174-179
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• 2005

The present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibers had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

• 보존과학연구
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• s.15
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• pp.137-147
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• 1994

This article is an introduction to : ICCROM PAPERCONSERVATION COURSE 1993" which I participated in, from July 28th 1993 to September 24th. The program was divided into two major sections. The first part deal with scienctific principles of paper conservation, covering structure and composition of paper and related materials, causes of deterioration and guidelines for preservation. It include chemistry for paper conservators and the history and technology of papermaking. Second part of the course emphasize practical conservation ; participants actually work together with specialists. Two weeks are dedicated to the Western approach to paper conservation. A selection of recent conservation treatments are discussed methodologically, demonstrated and performed. The same amount of time are devorted to a seminar on the conservation of fareastern paper objects. The aim is to exporse participants to different approrches and methodologies in paper consevation, to compare and discuss various tendencies and to learn lessons from other experiences that are applicable to one's own work.

• Journal of Forest and Environmental Science
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• v.23 no.2
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• pp.119-122
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• 2007

Actually, about 45% of total costs for wastewater treatment in a papermaking mill is spent for sludge disposal and the cost of chemicals used to improve the dewaterability of sludge takes much part of it. In order to reduce sludge disposal cost and to improve the efficiency of sludge treatment, it is necessary to minimize the amount of water contained within the sludge and hence to improve the dewaterability of the sludge. The objective of this study was to elucidate the way of improving the dewaterability of sludge. Three types of wastewater from a tissue paper mill, a printing paper mill and a newsprint mill were used and two types of high molecular weight flocculants (anionic PAM and cationic PAM) were used to treat the wastewater. Dewaterability of sludge was evaluated by measuring floc strength.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.49-56
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• 1993

This study was performed to investigate the pollution-free Korean traditional papermaking characteristics from paper mulberry by sulfomethylation pulping. Bast fibers were pulped by sulfomethylated cooking liquor, and by alkali and alkali-peroxide processes for the comparison. Sulfomethylated pulping resulted in the superior pulp with high yield and better quality compared to those of alkali and alkali-peroxide pulps. Since the pulp was so bright, there was almost no need additional bleaching. Pollutant loads of sulfomethylated pulping effluent were very low in terms of pH, turbidity and color compared to those of alkali. Pollution-free effluents was accomplished by simple filtering treatment with pine bark, charred rice hull and sawdust compost. Pine bark was the most effective in reduction rate of pollutants.