• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2007년도 춘계학술대회논문집
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• pp.206-218
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• 2007

• 펄프종이기술
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• 제39권4호
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• pp.29-37
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• 2007

The effects of latex particle size, basis weight of base paper and coating color concentration on the printing quality of coated paper were investigated. Coating colors were prepared with five types of latexes having different particle sizes. Coated papers were produced with high solid coating colors and with low solid coating colors in a industrial coater, respectively. In high solid coating colors, rheology modifier was used and GCC content was high. It was concluded that, in order to control binder migration and hence print mottle, latex particle sizes shall be controlled as well as formation, sizing degree and roughness of basis paper.

• 펄프종이기술
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• 제44권3호
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• pp.22-33
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• 2012

This study was carried out to investigate the characteristics of the lining papers which had been separated from six pieces of paintings and calligraphic works of the 18th and the 20th century. A total 20 kinds of lining papers were examined on the physical properties, colors, fiber morphology, and color reactions. The grammage and thickness of lining papers which had been used hanging-scroll type works were higher than those of folder types. On the other hand, the grammage and thickness of the first layer lining papers which had been separated from silk ground works were lower than those of paper ground works. All kinds of lining papers were colored from yellow to yellowish red because of unbleaching and deterioration. Through the examination on fiber morphology and color reactions, lining papers were verified that all of those were made from paper mulberry bast fiber but the first layer of the Mukjukdo. The lining paper which of the first layer of the Mukjukdo was verified that it was made from mixture of paper mulberry, hemp, and spruce pulps.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2002년도 추계학술발표논문집
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• pp.36-46
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• 2002

The accurate characterization of paper structure may provide critical information for ideal selection of raw materials and papermaking processes as well as for predicting the behavior and the quality of final paper products. In this study, local paper structure and the relationship among the structural parameters, thickness, grammage, apparent density and surface roughness of various handsheet and commercial paper samples were evaluated by using recently developed methods. A new concept of surface roughness was also introduced. The results demonstrate that there is significant overestimation in the measured thickness when using the conventional caliper method that originates from the surface roughness and poor paper formation. A novel non-contact thickness tester, referred to as the twin laser profilometer(TLP), provided results that were not subject to these artifacts and thus provided the local intrinsic thickness and consequently the local intrinsic apparent density.

• 펄프종이기술
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• 제41권5호
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• pp.50-58
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• 2009

Periodic variation of local paper structure was evaluated using two-dimensional fast Fourier transform (FFT) and spectral analysis. Since the periodic variation could originate from various sources and have different magnitudes and patterns depending on the origins, a complete analysis of local paper structure properties such as local grammage, local thickness, local apparent density and surface topography was proposed in this study. For a commercial copy paper, the individual periodic patterns for each local structural property were identified by using inverse FFT spectrums of the filtered spectrum. The spectral analysis of newsprint sample provided the period of variation quantitatively, which was useful in comparing the origins of the individual periodic patterns of the local structural properties.

• 펄프종이기술
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• 제46권1호
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• pp.11-17
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• 2014

This study analyzed the effects of specific factors on the fluorescence index of the fluorescent whitening agent (FWA) that is used for internal addition. The specific factors were identified by the literature review, and a statistical survey was carried out to analyze the effects of those factors on the fluorescence index. Bulk, grammage, fillers and internal sizing agents were selected as the specific factors. The paper samples were prepared with internal FWA in a laboratory. The fluorescence indices of the model papers were measured, and p-values of the specific factors on the fluorescence index were calculated by the SPSS program. Most of p-values were greater than 0.05, so the specific factors do not have a significant impact on the internal FWA fluorescence index.

• 펄프종이기술
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• 제40권5호
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• pp.36-41
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• 2008

Multi-ply sheet forming has many advantages including the possibility of using wide range of materials in a given structure, lowering production cost, making higher grammage products and so on. But, incorrect structure of sheet makes flow resistance higher so that it shows poor dewatering in press section. One of major factors that affect sheet structure and dewatering property is fines content in each layer. We, therefore, examined the press dewatering of multi-ply sheet that has the different fines content in each layer and the effect of fines distribution on physical properties of sheet to find a technology for optimum utilization of raw materials. In case of two layered sheet, the sheet which was composed of layers with the different flow resistance showed higher dewatering rate than one which has the same flow resistance. And the more difference in fines content for layers existed, the more dewatering occurred. For three layered sheets, dewatering is mainly dependent on fines content of bottom layer. Strength properties were affected by dewatering degree and multi-ply sheet structure.

• 펄프종이기술
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• 제46권6호
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• pp.78-86
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• 2014

Since cellulose nanofibrils (CNF) has large specific surface area and high water holding capacity, it is very difficult task to remove water from the CNF suspension. However, dewatering of CNF suspension is a prerequisite of following processes such as mat forming and drying for the application of CNF. In this study, we evaluated the drainage of cellulose fibers suspension under vacuum and pressure conditions depending on the number of grinding passes. Also, the effect of the addition of cationic polyelectrolyte on dewatering ability of CNF suspension was investigated. Regardless of dewatering condition, the total drained water amount as well as the drainage rate were decreased with an increase in the number of grinding passes. Pressure dewatering equipment enables us to prepare wet CNF mat with relatively higher grammage. The cationic polyelectrolytes improved the dewatering ability of CNF suspension by controlling the zeta potential of CNF. The fast drainage was obtained when CNF suspension had around neutral zeta potential.

• 펄프종이기술
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• 제39권3호
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• pp.30-35
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• 2007

Folding performance is very important in box manufacturing process using paperboard. To evaluate the folding performance of various paperboards, we measured the folding moment and folding behavior at the different folding angle and rate conditions. When linerboard with grammage of $300\;g/m^2$ was folded up to $90^{\circ}$, the compression break and delamination of sheet were observed. The maximum folding moment was little affected by folding angle, but it was increased logarithmically with folding rate. And the effect of paperboard thickness was significant. The maximum folding moment of MD sample was higher than one of CD sample by 40%.

• 펄프종이기술
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• 제43권1호
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• pp.17-22
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• 2011

The conventional coated paper has many functional problems for printed RFID tag. This study was carried out in order to evaluate the effect of coating color components on conductivity of printed coated paper. It has been well known that the efficiency of printed RFID tag is influenced by surface properties of substrate. The required properties for suitable substrate of printed RFID tag are high smoothness and waterproof property. In this study high grammage base paper surface sized with PVA was used. Coated paper was manufactured with five different formulations. Types of coating pigments and dosage of latex were varied. It was obtained high smoothness and also less binder demand with clay than GCC. On the other hand, suitable surface resistance and smoothness of coated paper for RFID tag was obtained with 20% of latex. Besides it shows the possibility of using coated paper for printed RFID tag.