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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Korea Technical Association of The Pulp and Paper Industry
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Journal DOI :
Korea Technical Association of the Pulp and Paper Industry
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Volume & Issues
Volume 47, Issue 6 - Dec 2015
Volume 47, Issue 5 - Oct 2015
Volume 47, Issue 4 - Aug 2015
Volume 47, Issue 3 - Jun 2015
Volume 47, Issue 2 - Apr 2015
Volume 47, Issue 1 - Feb 2015
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Studies on Application of Spray of Nano-fibrillated Cellulose to Papermaking Process
Lee, Kwang Seob ; Kim, Chang Geun ; Lee, Jae Hoon ; Lee, Tai Ju ; Ryu, Jeong Yong ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 5~12
DOI : 10.7584/ktappi.2015.47.4.005
In recent years, it had focused on the improvement of paper properties by addition of NFC (Nano-fibrillated Cellulose). Although the addition of NFC to wet-end of papermaking process could be suggested as a new solution to improve the strength properties of paper, it was not possible to avoid the bad drainage caused by the added NFC's chocking pores of wet web. Instead of the direct addition to wet-end, spraying of NFC to web in wire-section was tried in this study and evaluated by checking various paper properties including surface smoothness, tensile strength, folding endurance and stiffness. According to the increase of spraying amount of NFC, above mentioned paper properties were enhanced without excessive deterioration of drainage. Compared with direct introduction to wet-end, spraying could be regarded as a more proper method to enhance the surface smoothness and strength properties of paper.
Chlorine Dioxide Bleaching Properties of Sugarcane Bagasse Pulp and Oil Palm Trunk Pulp
Lee, Jai-Sung ; Shin, Soo-Jeong ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 13~20
DOI : 10.7584/ktappi.2015.47.4.013
Soda-AQ pulp made from sugarcane bagasse (SCB) and oil palm trunk (OPT) were bleached in element chlorine free (ECF) sequence. Bleached SCB and OPT pulp was achieve higher brightness than 85.0% ISO. Viscosity of SCB bleached pulp and OPT bleached pulp were achieved 18-27 cPs and 18-26 cPs. In 7.8% active chlorine dioxide addition, bleached SCB pulp was shown 88.7% ISO brightness and 20.4 cPs viscosity. And bleached OPT pulp was shown 88.5% ISO brightness and 18.8 cPs viscosity with 7.8% active chlorine dioxide addition.
Evaluation of Pitch Pine for Bioethanol Production by Organosolv Pretreatment
Youe, Won-Jae ; Kim, Yong Sik ; Kang, Kyu-Young ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 21~29
DOI : 10.7584/ktappi.2015.47.4.021
In this study, the feasibility of utilizing wood chips from pitch pine (Pinus rigida) was evaluated for bioethanol production by an organosolv pretreatment and enzymatic saccharification. When wood chips from pitch wood were pretreated with 75% (v/v) ethanol and 1.7% sulfuric acid as a catalyst at H-factor 2000, average pulp yield was 43.3%, which pretreated wood fibers showed higher glucan (55.8%) and lower lignin (12.2%) contents than untreated control (43.9% glucan and 27.8% lignin). After enzymatic saccharification, the organosolv pulps with 56.2% delignification rate reached above 97% conversion rate of cellulose to glucose. These results indicated that increasing the delignification rate causes micro pores on the surface of organosolv pulps resulting in improved the accessibility of enzyme onto the substrate. Moreover, it was in agreement with the SEM examination of wood fibers.
Development of Hybrid Calcium Carbonate for High Loading Paper (I) - Manufacture and Application of Hybrid Calcium Carbonate -
Jung, Jae Kwon ; Seo, Yung Bum ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 30~37
DOI : 10.7584/ktappi.2015.47.4.030
Needs for high ash loading in printing paper increase as green house gas (GHG) emission regulation becomes more stricter and pressure of lowering paper production cost increases. To meet the needs, a new type of filler was developed. The mixture of ground calcium carbonate (GCC) and calcium oxide was pre-floccuated with polyelectrolyte and further treated with carbon dioxide to form new calcium carbonate between GCCs. The final products were called as hybrid calcium carbonate (HCC), and its properties were compared to the GCC and the pre-flocculated GCC. Results showed increase in tensile, smoothness, opacity, and bulk for HCC.
Fold Cracking of High Grammage Coated Paper Depending on Pulp Composition and Structure of Base Paper
Sim, Kyujeong ; Youn, Hye Jung ; Oh, Kyudeok ; Lee, Hak Lae ; Yeu, Seung Uk ; Lee, Yong Min ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 38~45
DOI : 10.7584/ktappi.2015.47.4.038
Fold cracking is one of quality troubles of coated papers. In this study, the fold cracking of high grammage (
) coated paper made with the different pulp composition and layer structure of base paper was investigated. The single layered, high grammage base paper was prepared by mixing of hardwood and softwood bleached kraft pulp fibers with the different ratios. The high grammage coated paper showed the higher fold cracking than low grammage coated paper because of the increase in thickness. The increase in the content of softwood pulp fibers reduced the fold cracking in the case of high grammage coated paper. When the creasing process was conducted before folding process, the fold cracking of coated paper decreased. By manufacturing the base paper with multiply structure, the fold cracking of coated paper could be reduced significantly, especially when the BCTMP and OCC were used as a middle layer and the creasing process was carried out. The delamination of layers in base paper affected the fold cracking positively.
Effect of Dual Polymer System using Polyvinylamine for Paper Strength
Choi, Jae-Hoon ; Ryu, Jeong-Yong ; Kim, Bong-Yong ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 46~53
DOI : 10.7584/ktappi.2015.47.4.046
Paper strengthening system of PVAm (polyvinylamine) has been used with strong negative charge polymer for electrostatic neutralization due to strong positive charge of PVAm. Recently, because of the controversy caused by the possibility of remaining PAM monomers in white water, a search for paper strength agent that can substitute for PAM was suggested. Therefore, this study was carried out to evaluate a dry strength polymer of PVAm. Starch and CMC were used as a substitute for PAM. The dual polymer system of PVAm and anionic charge control agent such as anionic starch or CMC (carboxy methyl cellulose) were found to be very effective as strength agent compared to the chemicals based on acrylamide.
Effects of Kneading Concentration on Characteristics of HwBKP Fibers
Seo, Ji-Hye ; Choi, Kyoung-Hwa ; Cho, Byoung-Uk ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 54~59
DOI : 10.7584/ktappi.2015.47.4.054
In this study, effects of kneading concentration on characteristics of hardwood bleached kraft pulp (HwBKP) fibers were elucidated. A laboratory two-shaft kneader was utilized for kneading. Kneading concentration was varied in the range of 15-30% (w/w) and the number of kneading treatment was adjusted between 0 and 6 passes. It was found that kneading concentration influenced fiber characteristics. At 15% of pulp concentration, fiber length slightly increased with increasing the number of kneading passes, while other morphological properties such as fiber width and curl decreased: fiber straightening occurred. In addition, the increase in WRV and the decrease in CSF were the largest at 15% kneading concentration, meanings that fibrillation mainly occurred. In contrast, at higher kneading concentration exceeding 20%, fiber deformation like curl was mainly occurred. Also, at kneading concentration of 20% and 30%, fiber length decreased with the number of kneading passes while other morphological properties such as fiber width, and WRV increased. Severe fiber entanglement was found at 30% kneading, which shall be removed during papermaking.
Mechanical Property Variations of Handsheets by Mixing Ratios of Sw-BKP, Hw-BKP, and PVA Fibers
Yoon, Sang-Gu ; Park, Jong-Moon ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 60~65
DOI : 10.7584/ktappi.2015.47.4.060
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.
Studies on the Recovery of Useful Materials from Disposable Diaper Waste using Pilot Stock Preparation Units
Lee, Tai Ju ; Nam, Yoon Seok ; Park, Jeong Eun ; Jo, Jun Hyung ; Ryu, Jeong Yong ; Lee, Ho Sun ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 66~75
DOI : 10.7584/ktappi.2015.47.4.066
Disposable diaper waste is consisted of plastic, fiber, and SAP (Super Absorbent Polymer). They are valuable to be used as raw materials of other products including plastic blocks and pulp mold. Nevertheless, disposable diaper waste have been disposed by landfill and incineration without recycling. Due to strict environmental regulations it is necessary to develop fractionation technique to recycle the disposable diaper waste. In this study the fractionation technique using pilot-scale stock preparation units was investigated. Process for separation of plastic and fibers from disposable diaper waste was composed by the combination of pilot-scale pulper, drum screen, screen and cleaner. Recovery rate of plastics and fiber was checked according to the various operating conditions. In drum screen, recovery rate of plastic was high when the cut size of disposable diaper waste was
. The highest recovery rate of fiber was achieved with 0.3 mm slot screen. It is important to control the neutral state of SAP for improvement of recovery rate of fiber since SAP can be swelled easily in water. Therefore SAP can be controlled efficiently by the addition of calcium chloride into the pulper. Consequently recovery rates of plastics and fibers were over 90 and 80% under the optimum pilot operating conditions.
Development of Hybrid Calcium Carbonate for High Loading Paper (II) - Comparison with GCC -
Jung, Jae Kwon ; Seo, Yung Bum ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 76~80
DOI : 10.7584/ktappi.2015.47.4.076
In filler loaded paper, the size of the filler affects its strength, optical and surface properties. As the size of the filler increases, tensile strength and bulk usually increases, opacity decreases, and smoothness becomes worse. Pre-flocculation of GCC (grounded calcium carbonate) makes large diameter flocs at aqueous medium that consists of multiple GCC particles, but they collapse to 2-dimensional shape in dried paper and makes low bulk paper. The hybrid calcium carbonate (HCC) that was made by in-situ
formation between GCC in aqueous medium made high bulk paper without harming tensile strength, bulk, opacity, and smoothness. The GCC that has equivalent size as HCC failed to make high opacity and smoothness as much as HCC.
Effect on Bleaching Efficiency by Chelating Treatment in Sugarcane Bagasse DEDP Bleaching Process
Lee, Jai-Sung ; Song, Woo-Yong ; Park, Jong-Moon ; Shin, Soo-Jeong ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 81~87
DOI : 10.7584/ktappi.2015.47.4.081
Soda-AQ pulp made from sugarcane bagasse (SCB) were bleached in element chlorine free (ECF) sequence. To reduce chlorine dioxide use, final peroxide bleaching was introduced. Prior to peroxide bleaching, different chelating chemicals were applied for comparative analysis in ISO brightness and viscosity. When using equal total chlorine dioxide usage (4.5%), bleached SCB pulp using chelate and hydrogen peroxide (DEDQP) was reached 86.8% (DTPA), 86.4% (EDTA) ISO brightness, whereas bleached pulp using only hydrogen peroxide (DEDP) reached at 81.2% ISO brightness. Viscosity of DEDQP bleached pulp was 25.6 cPs (DTPA), 25.2 cPs (EDTA), And DEDP bleached pulp was shown 18.0 cPs viscosity. Decreasing of transition metal by chelate process led to improvements in final brightness along with higher viscosity. Due to EDTA is 5-7 times cheaper than DTPA, EDTA is recommended as chelating chemical prior to peroxide bleaching.
Comparison of Froth-flotation Efficiency between Fatty Acid and Non-ionic Surfactant Added to Recovered Paper with Increased Mixing Ratio of OMG
Seo, Jin Ho ; Lee, Kwang Seob ; Lee, Tai Ju ; Lee, Myoung Ku ; Ryu, Jeong Yong ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 88~95
DOI : 10.7584/ktappi.2015.47.4.088
The main sources of recovered paper for newsprint are old newsprint (ONP) and old magazine (OMG). Recently, a lot of advertisement flyers are flowing into bales of ONP and portion of OMG is increasing in recovered paper because the consumption level of coated paper increases. In this study, nonionic surfactant and fatty acid were used as the de-inking agent for froth-flotation process of mixed recovered paper to investigate the effect of increased mixing ratio of OMG. De-inking efficiency of nonionic surfactant decreased as the mixing ratio of OMG increased; ink removal efficiency of froth-flotation is poor, however, the reject ratio increases due to ash from OMG. In comparison with nonionic surfactant, the ash from OMG had a little effect on reject ratio and optical properties of fatty acid applied flotation accept. If nonionic surfactant and fatty acid are added to pulper and flotation cell sequentially, excessive ash from OMG may not give an adverse effect on de-inking efficiency of mixed recovered paper.
Development of New Organic Filler Made from Rice Husk by Paperboard Mill Trials
Lee, Ji Young ; Kim, Young Hun ; Kim, Chul Hwan ; Sung, Yong Joo ; Wi, Sang Wook ; Park, Jong-Hea ; Kim, Eun Hea ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 96~101
DOI : 10.7584/ktappi.2015.47.4.096
In the previous study, we investigated the physical properties of new organic fillers made from major agricultural byproducts, including rice husks, peanut husks and garlic stems, and we estimated that rice husk was the best candidate for use as new organic fillers in paperboard. In this study, an organic filler prototype was produced with rice husk and the mill trials were carried out in a white liner chipboard (duplexboard) mill. The rice husk organic filler was added to the middle ply of SC
to determine the optimal conditions for the manufacture of rice husk organic fillers. The mill trials were performed three times and the bulk improvement and drying energy reduction were measured to identify the functionality of the rice husk organic filler compared to that of the commercial wood powder. In the first mill trial, the test failed because the surface roughness of the duplexboard had deteriorated after the rice husk organic filler was added to the OCC stock. As all of the particles remaining on the 60 mesh sieves were removed and the particle size was decreased by increasing the length of the grinding process, the surface roughness of the duplexboard did not be deteriorated in the second mill trial. However, the bulk improvement and drying energy reduction were not observed. In the final mill trial, as the particle size of the rice husk organic filler was controlled by increasing the portion of particles passing through the 60 mesh sieves and remaining 100 mesh sieves, higher bulk improvement and drying energy reduction were acquired compared to the commercial wood powder.
Application of Agricultural Cultivation Paper Treated with Water Repellent
Kim, Kang-Jae ; Jung, Jin-Dong ; Ahn, Eun-Byeol ; Eom, Tae-Jin ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 102~108
DOI : 10.7584/ktappi.2015.47.4.102
Agricultural cultivation papers treated with water repellent were investigated in order to analyse mechanical properties and durability. The water repellency was optimal when papers are treated with Wb and Sa water repellents. Also, WCPs with 5% water repellent were more effective than those of 3 and 10%. In addition, water repellency of WCPs with Wb and Sa water repellents were kept constant in correlation with aging time. Finally, WCP with Wb water repellent possesses efficiency in terms of mechanical properties and durability.
Bleachability of Hemp Bast Fiber by Chlorine Dioxide
Kim, Jun-Kyu ; Choi, Kyoung-Hwa ; Seo, Jin-Ho ; Lee, Myoung-Ku ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 109~114
DOI : 10.7584/ktappi.2015.47.4.109
In this study, the effects of chlorine dioxide (D) bleaching conditions on the delignification of hemp bast fiber were elucidated. Chlorine dioxide bleaching was carried out through three stages (DED) and five stages (DEDED), respectively. Applied amounts of chlorine dioxide at
stages were varied to find the optimum bleaching condition. It was found that the optical properties of its handsheet as well as the delignification of hemp bast fiber increased as the concentration of chlorine dioxide at
stage increased. It was also notable that the bleachability of the DEDED bleaching stages was slightly more effective than that of the DED bleaching stages. The burst index of the handsheets made with bleached hemp bast fiber was higher than that of the unbleached samples, but the burst index of these samples decreased as their delignification increased. These results indicated that the higher concentration of chlorine dioxide at
stage was major factor to improve the bleaching efficiency of hemp bast fiber.
Effect of Ground Calcium Carbonate Modified by Washless Multilayering of Polyelectrolytes on Paper Quality
Lee, Jegon ; Im, Wanhee ; Sim, Kyujeong ; Lee, Hak Lae ; Youn, Hye Jung ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 115~126
DOI : 10.7584/ktappi.2015.47.4.115
In this study, we investigated influence of ground calcium carbonate (GCC) modified by washless multilayering of polyelectrolytes on paper quality. Three layers of polyelectrolytes (cationic starch/anionic polyacrylamide/cationic starch) were formed on the surface of GCC using laboratory inline washless polyelectrolytes multilayering system, which was called inline LbL GCC. Base papers were prepared with untreated GCC or inline LbL GCC using a laboratory handsheet former. These handsheets were coated with rod coater, and then printed by black ink. Properties of base paper and fold crack of coated paper were evaluated. Base paper with inline LbL GCC showed much higher mechanical strength in terms of tensile index, strain, internal bond strength, and folding endurance. The fold crack of coated paper with inline LbL GCC occurred more frequently compared to coated paper with untreated GCC. This might be due to highly improved internal bond strength of base paper, which resulted in smaller delamination that played a role of stress dissipation. It would be recommended to design a proper coating layer in order to prevent fold crack.
Influence of Animal Glues Application for Painting Restoration on Paper Characteristics
Park, Mi Seon ; Kim, Hyoung-Jin ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 127~135
DOI : 10.7584/ktappi.2015.47.4.127
Artists have been used animal glues for a long time as binding and sizing materials of paintings in many countries including Korea. Since animal glues as a binding material lose their own adhesive strength by aging, pigment particles or pigment layers are easily detached from painting surface. Restaurators prefer to use animal glues for consolidation of pigment particles or pigment layers because artists use animal glues as a binder for their painting works. It is widely known that animal glues have different characteristics such as viscosity, stability on water etc. But there are still a few requirements to consider their stabilities for the restoration of paintings. Therefore, this study was aimed to evaluate of stability and efficiency of animal glue applications. The efficiency of animal glue application was decreased with increasing the concentration of animal glue solution. This result means the simple tendency, but does not representative data for other animal glues made from same raw materials. In most cases, the surface and mechanical characteristics of animal glues are dependent on some factors, like viscosity and concentration of animal glue solution.
Effect of the Modification of PCC with NCC on the Paper Properties
Ming, He ; Lee, Yong Kyu ; Won, Jong Myoung ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 136~143
DOI : 10.7584/ktappi.2015.47.4.136
It is well known that the use of PCC as a filler for printing paper making brought about the serious deterioration of strength properties of paper, although PCC could be helpful to reduce the energy consumption. The use of modified PCC with NCC was tried to solve and/or reduce the strength deterioration problem. NCC was prepared from SwBKP by the acid hydrolysis. There was no significant changes in chemical properties and crystalline structure. However the cyrstallinity of NCC was higher than those of SwBKP. The different dosage of NCC was applied to modify the properties of PCC. 0.1% of NCC dosage was enough to improve ash retention and paper properties. The use of modified PCC with NCC as a filler improved ash retention, bulk, opacity and formation without the serious deterioration of strength properties. Thus the use of modified PCC with NCC might be helpful for not only reduction of energy consumption but also increase of filler dosage without the significant sacrifice of strength properties by the optimization of retention system.
Chemical Characteristics of Cell Wall in Pinus thunbergii Parl. Grown with High Salinity
Kim, Kang-Jae ; Eom, Tae-Jin ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 144~150
DOI : 10.7584/ktappi.2015.47.4.144
Stems of Pinus thunbergii Parl. grown with high salinity were analyzed for chemical characteristics. Stem of 2 years was rich in soluble compounds and stem of 3 years reduced the amount of the soluble compound. But, the lignin content have not seen a large change. Also, Klason lignins of stem of 2 and 3 years has not changed in nitrogen and hydrogen content. In Klason process, it was significantly increased the carbon concentration due to the hydrolysis of the carbohydrate. In addition, the accumulation of xylan from Pinus thunbergii Parl. with salinity treatment were increased noticeably. Finally, functional group of Pinus thunbergii Parl. with salinity treatment were not changed.
Studies on the Accelerated Aging Characteristics of Paper Records by Gaseous Air Pollutants
Jeong, So-Yoon ; Jeon, Soo-Yeon ; Baek, So-Ra ; Jeong, Hyun-Seok ; Lee, Jin-Hee ; Kim, Hyoung-Jin ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 151~159
DOI : 10.7584/ktappi.2015.47.4.151
Paper records were generally degraded by some factors from atmospheric environments, like temperature, relative humidity or air pollutants. In this study, the degradation behavior of paper records by single or mixed gases of
, HCHO and TVOC was evaluated. The mechanical, optical and chemical properties of 4 kinds of paper (acid and neutral-based printing paper, traditional Hanji, and filter paper) were directly and indirectly affected by gaseous harmful materials. The brightness and
value in all papers were slightly increased by accelerated aging under gaseous HCHO and TVOCs, but highly decreased by conditions under gases
. The optical properties of paper records were most vulnerable in acid-based paper and high stable in filter paper and traditional Hanji by air pollutant degradation. The aging treatments under mixed gas pollutants including
resulted in decrease of physical, mechanical and optical properties of paper, so it was supposed that the concentration of
gas would be strictly controlled for optimum indoor air quality management in domestic storage centers for paper records.
Methods for Improving the Applicability of Wood Powder Spacers to Liner Board Manufacturing
Yoon, Do-Hyun ; Sung, Yong Joo ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 160~167
DOI : 10.7584/ktappi.2015.47.4.160
The reduction of energy consumption in papermaking process has been considered as one of the major issue in the paper technology. The energy efficiency of paper mill becomes more significant for the mill which manufacture the board grade products such as linerboard with recycled paper such as OCC. The application of lignocellulose spacer to the board grade paper stock would be the feasible solution by increasing the paper bulk and the drying efficiency. The major defects originated from the application of the lignocellulose spacer could be the loss of strength properties. In this study, the ways for improving the strength properties of the spacer-added linerboard were suggested and evaluated. The effects of the addition of various types polyelectrolytes were tested and the different methods of polyelectrolytes were applied for finding the efficient way. The pretreatments of lignocellulose spacer with the polyelectrolytes during wood spacer hydration resulted in the higher strength properties than the typical application method such as the addition to the mixed stock. Multilayer treatments of the spacer with polyelectrolytes were also evaluated and leaded to the higher strength properties with the similar bulk improvement.
Historical Review on the Korean Paper Folding Crafts
Jeon, Cheol ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 168~176
DOI : 10.7584/ktappi.2015.47.4.168
The history of paper folding had continued before that the paper manufacturing technique was spread in the 3rd century and it was used for witchcrafts and rituals. Fold means as was used with the word Cheop and Jeopji. In the Three Kingdoms period, the conical hat with fabric spread as customs, then it was made of the paper that led the popularization of paper folding form the early Joseon Dynasty. Paper crafts and living things with paper are mostly derived from fabrics except the paper written for saint's name related God. In the period of the tribe nation, witchcrafts and rituals brought to Japan via the Korean Peninsula, as a result Kami which means God in Japanese that becomes the paper. The first folding fan was made to develop from the fan, Baekseopsun in the end of Goryeo Dynasty. It was an outstanding application of paper folding crafts. Since the early Joseon Dynasty, paper flower folding has considered as the virtue of savings and has developed one of the Korean traditional paper arts. Paper folding has also developed in the practical uses like the other Korean paper arts but paper folding that was developed as seasonal customs, playing or religious purpose showed a different trend from Korean paper arts.
The Principles of Fractal Geometry and Its Applications for Pulp & Paper Industry
Ko, Young Chan ; Park, Jong-Moon ; Shin, Soo-Jung ;
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 47, issue 4, 2015, Pages 177~186
DOI : 10.7584/ktappi.2015.47.4.177
Until Mandelbrot introduced the concept of fractal geometry and fractal dimension in early 1970s, it has been generally considered that the geometry of nature should be too complex and irregular to describe analytically or mathematically. Here fractal dimension indicates a non-integer number such as 0.5, 1.5, or 2.5 instead of only integers used in the traditional Euclidean geometry, i.e., 0 for point, 1 for line, 2 for area, and 3 for volume. Since his pioneering work on fractal geometry, the geometry of nature has been found fractal. Mandelbrot introduced the concept of fractal geometry. For example, fractal geometry has been found in mountains, coastlines, clouds, lightning, earthquakes, turbulence, trees and plants. Even human organs are found to be fractal. This suggests that the fractal geometry should be the law for Nature rather than the exception. Fractal geometry has a hierarchical structure consisting of the elements having the same shape, but the different sizes from the largest to the smallest. Thus, fractal geometry can be characterized by the similarity and hierarchical structure. A process requires driving energy to proceed. Otherwise, the process would stop. A hierarchical structure is considered ideal to generate such driving force. This explains why natural process or phenomena such as lightning, thunderstorm, earth quakes, and turbulence has fractal geometry. It would not be surprising to find that even the human organs such as the brain, the lung, and the circulatory system have fractal geometry. Until now, a normal frequency distribution (or Gaussian frequency distribution) has been commonly used to describe frequencies of an object. However, a log-normal frequency distribution has been most frequently found in natural phenomena and chemical processes such as corrosion and coagulation. It can be mathematically shown that if an object has a log-normal frequency distribution, it has fractal geometry. In other words, these two go hand in hand. Lastly, applying fractal principles is discussed, focusing on pulp and paper industry. The principles should be applicable to characterizing surface roughness, particle size distributions, and formation. They should be also applicable to wet-end chemistry for ideal mixing, felt and fabric design for papermaking process, dewatering, drying, creping, and post-converting such as laminating, embossing, and printing.