• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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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.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.69-81
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• 1997

Up to now 5 Voith Sulzer paper machines with multi-layer headbox and Gapfor-mer are sucessfully running on papckaging papers. Linerboard, testliner and corugating medium is produced in the basis weight range from 105 to 275 $g/m^2$ at machine speeds up to 900 m/min. The nest one, starting up in Oct. ｀96 in Germany, will be the world＇s fastest paper machine for packaging papers. The 5.6 m wide machine is designed for a maximum operating speed of 1200 m/min. Approx. 220.000 tons of corrugating medium and testliner based on 100% waste paper in the basis weight range from 90 to 160 $g/m^2$ will be produced each year. An expansion stage planned for the future is intended to increase annual output to 280.000 tons. This machine will not only be the fastest one for packaging papers, it also comprises all described innovative key components which are available today in order to fulfill growing demands of the future with regard to quality and productivity. The concept of this advanced machine is shown in Fig. 9.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.4 s.107
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• pp.1-8
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• 2004

Linerboards and corrugating mediums are being produced using recycled old corrugated containers (OCC) as major raw materials. The utilization rate of recycled fibers is ex­pected to increase further in the future to reduce raw material cost. Use of recycled fibers as raw materials for linerboard, however, causes many problems for papermakers. As the utilization rate of recycled fiber and number of recycling of fibers increases, quality and process problems including strength reduction and deterioration of machine runn­ability will increase. To overcome the problem of strength reduction associated with the use of recycled fibrous materials for producing quality linerboards, diverse extensive research efforts and new technological approaches have been taken. In this study, disintegration characteristics of aee was evaluated by determining the unslushed contents. The amount of unslushed content of KOCC was lower than AOCC. But contaminants content of KOCC was higher than AOCC. As the consistency in disintegration increased, the amount of unslushed fiber content decreased.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.1
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• pp.44-51
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• 2009

Proper test methods and instruments for evaluating score or creasing crack have not been provided, although score crack trouble occurs frequently in manufacturing corrugated containers. Because existing creasability tester has the limitation of the available thickness of test piece and folding rate, it cannot be used for corrugated fiberboards with high thickness. In this study, we developed the laboratory test instrument and the method to determine the score or creasing crack of corrugated fiberboard. This instrument can evaluate folding resistance of corrugated board without restriction on the folding rate and thickness of specimen. Corrugated fiberboard had the different folding behavior from linerboard when it was creased. By using this test machine, score crack can be objectively determined by folding test piece to the certain folding angle with constant folding rate.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.1
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• pp.24-29
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• 2001

The base paper of corrugated board is mainly produced from Korean old corrugated container (KOCC), and thus the recycling rate of KOCC is very high. However, there is a problem that the pulp quality is very low while the recycling rate of OCC is high. The fines content in KOCC, the main source of the corrugated board, amounts to nearly the half of the total stock, and its formation increases as recycling process repeats due to the hornification of fiber. There have been attempts to improve the drainage property of OCC by increasing the headbox concentration of the paper machine or by applying drainage-promoting polymer additives. However, these conventional methods have problems of weakened paper strength and lowered converting fitness caused by paper formation hindrance. The strength of linerboard could not be increased in case KOCC is used, because hornified OCC pulp can-not be sufficiently refined due to the lowered drainage property caused by fines formation. We studied about a new technique consisting of froth-flotation for fractionating pulp stock into a long fiber portion and fines fraction. This study will be developed in order to enhance the drainage and strength properties of a recycled OCC pulp by selective treatment of flocculant on fractionated OCC Fines.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.59-65
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• 2005

There are accumulations of remained chemical additives and contaminants in the process water of semi-closed linerboard mill. High temperature of the process water aggravates the anaerobic digestion of contaminated process water and causes the generation of hazardous gases, which are from the biological reaction of varied additives and contaminants. The hydrogen sulfide in the gases easily combine with moisture in the air, and become sulfuric acid, which causes corrosion of paper machinery. This hydrogen sulfide is from the reduction of sulfate ions in the process water, and the sulfate ions are mostly from the alum. We changed the alum to PAC (Poly Aluminum Chloride). The results were preventing generation of hydrogen sulfide, and equivalent sizing effect by the use of PAC.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.14-22
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• 2016

Pulping is a stage that can change fibrous raw materials into pumpable slurry. Recovered paper can be defibrated to individual fibers by shear stress generated by rotation of a rotor and water. Disintegration of recovered paper is more complicated than that of chemical pulp. When disintegration of recovered paper is poor, screening and cleaning efficiency will be worse and properties of paper will also be deteriorated. Therefore, pulping is an important treatment for improvement of availability of recovered paper and process runnability. In this study, degrees of disintegration of KOCC obtained from a linerboard mill was analyzed with a pilot-scale screen. Flake removal of KOCC slurry was performed by a pilot screen. Simple pumping action gave a positive effect on disintegration of KOCC. After pumping for 10 minutes, paper strength increased without the change of water retention value and fibrillation of KOCC slurry. This phenomena can be explained by modification of hornified surface of KOCC fibers by shear stress generated by pumping. Consequently, disintegration efficiency of KOCC can be enhanced by control of retention time at pulper or an agitation power at chests of papermaking process.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.69-75
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• 1999

This study was performed to investigated the application of mixed resins for corrugated container board. The corrugated container board yields a sandwich structure in which a linerboard material is glued to a corrugated medium . Now, manufacturing corrugated container boards don't provide sufficient strength, and result in box failure during shipping . Therefore improvement of box strength is necessary . In this study, we intend to improve box strength by improving corrugated medium strength with mixed resins and to find the optimum treatment condition of this resins. First, we tried to mixed resins as Starch+CMC, Starch_Irea, CMC+Urea, Second, investigated to applicability of this resins for corrugated medium , and the third, measured tensile index, burst index, and edgewise compression index on liner, medium paper, and single faced corrugated container board. In this test results, we obtained that the improvement ratios of tensile index in liner and medium paper were approximately 80-185%, 60-118% , respectively. The respecting improvement ratios of edgewise compression index of single faced corrugated container board was approximately 91-124%, relatively. In addition, we concluded that optimum condition in mixing ratio was 1 :3 with CMC + Urea and the ap[plication amounts was 9% on materials. Fro manufacture of corrugated container board, optimum condition in mixing ratio was 1 : 3 with 5% CMC +Urea , because of considering to improvement of strength on cost.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.25 no.3
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• pp.131-137
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• 2019

Carton clamps, one of forklift attachments, allow users to quickly handle shipping units such as unitized loads, large shipping cases, or crates without the requirement of pallets. As the use of palletless handling by clamp trucks increases, so does the need for simulation research on clamp truck handling. The frictional characteristics for various contact conditions of corrugated paperboards and their constituent boards were analyzed to obtain the data needed in the computer simulation for the handling of carton clamp truck. The overall mean of static-frictional coefficients between selected corrugated paperboards was 0.38 (±0.01), which was 1.3~1.6 times greater than 0.23~0.29 of the frictional coefficients between boards. The overall mean of static-frictional coefficients between the corrugated paperboards and the rubber contact pad was 0.82 (±0.02), which was about 1.1 to 2.8 times greater than 0.29~0.78 of the static-frictional coefficient between the linerboard and the rubber contact pad. The overall mean of kinetic-frictional coefficients between the corrugated paperboards was 0.35 (±0.01), and 0.76 (±0.02) between the corrugated paperboards and the rubber contact pad.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.4 s.112
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• pp.18-25
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• 2005

The mechanical strength is the prime requisite for linerboard and corrugating mediums. Repeatedly recycled OCC fibers show less suitable property for papermaking mostly due to hornification and reduced fiber length. To overcome these problems many researches including fractionation, enzymatic treatment, and chemical or mechanical treatments of fibers have been carried out. In this study, the effect of mechanical treatment by high consistency pulping on the characteristics of recycled fibers as well as mechanical properties of sheets were investigated. Results on the strength properties of handsheets made of recycled fibers that were treated to same freeness level by beating and high consistency pulping, respectively, showed that beating treatment was more efficient in improving strength. Drainage and recycling potential of the fibers treated by high consistency pulping, however, were expected to be superior to beating because fines content and fiber length didn't change significantly.