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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Korea Technical Association of The Pulp and Paper Industry
Journal Basic Information
Journal DOI :
Korea Technical Association of the Pulp and Paper Industry
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Volume & Issues
Volume 32, Issue 5 - Dec 2000
Volume 32, Issue 4 - Dec 2000
Volume 32, Issue 3 - Sep 2000
Volume 32, Issue 2 - Jun 2000
Volume 32, Issue 1 - Apr 2000
Selecting the target year
Effect of Beating and Pressing on Fracture Toughness of Paper
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 1~9
As the speed of the paper machine and printing press increases, the dependency of the production efficiency upon the frequency of web break increases. It is believed that flaw or crack that presents in paper is one of the most important for web break. Runnability of papers on the paper machine could be evaluated by measuring fracture toughness. In this paper the effect kof beating and pressing on the runnability was investigated using handsheets made from softwood bleached kraft pulp beaten to different freeness. Pressing pressure was also varied to obtain different levels of sheet consolidation. Density, tensile strength, and J-integral of the handsheets were evaluated. For measuring J-integral either a single specimen method or RPM method was employed. Results showed that the density and tensile strength were improved as beating and pressing increased because of increased interfiber bonding. J-integral increased with beating until the CSF reached 400mL. No significant difference in J-integral, however, was observed afterward with the increase of beating. And it appeared to be due to acceleration of the stress concentration around the crack that exists on the fiber wall of the sheet when cracks exists.
Effect of Refining Load on the Drainage Characteristics of Pulp
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 10~17
The change of fiber length, freeness, initial forming drainage velocity, specific filtration resistance, final drainage time and wet web dryness were measured to investigate the effect of the refining load on the drainage characteristics of pulp. The arithmetic average fiber length after refining with higher refining load was shorter than that obtained with lower refining load. Higher refining load decreased initial forming drainage velocity, final drainage time and wet web dryness. The refining load also affected the relationship between freeness and specific filtration resistance, initial forming drainage velocity, final drainage time. It was found that the specific filtration resistance is better than freeness to predict the drainage characteristics of pulp and the wet dryness.
Recycling of Wastepaper(IX) -The Effect of Flotation Conditions on the Efficiency of KOCC Fractionation and Principles of Fines Fractionation-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 18~26
In order to investigate the influencing factors in flotation fractionation, flotations were performed at varied conditions. The selectivity of fines fractionation was mainly affected by long fiber flocculation degree and if there were not sufficient flocculation of long fibers, more loss of long fibers could not be avoided. The amount of flotation rejects were totally dependent on the stability of froth floated on the stock surface. Only small size fines could stabilize the froth as they hindered the drainage of liquid lamella in flotation-froth. More flotation reject and better flocculation of long fibers were two important factors for improving flotation. Changing a flotation flux or an air-mixing ratio to increase the flocculation of fibers increased long fiber ratio in the reject. In order to satisfy the both conditions of reducing long fiber loss and of increasing flotation reject, search of fractionation promoter is needed.
Recycling of Wastepaper(X) -Improvement of Fines Fractionation through Multi-Stage Froth-Flotation and Addition of Cationic Polyelectrolyte as a Fractionating Promoter for OCC Flotation-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 27~33
A new technique for fractionating pulp stock into a long fiber portion and fines fraction was developed by KRICT in order to enhance the drainage and strength properties of recycled OCC pulp. In order to investigate the effect of fines contents in stock and stages of flotation on fractionation efficiency, flotations were performed at varied fines contents and flotation stages. Based on the result of multi-stage flotation fractionation it could be said that fines smaller than 15
stabilize flotation froth of OCC. Although the amounts and the fines contents of flotation reject could be increased by multi-stage flotation fractionation of OCC, flotation stages more than 3 times were found to be inefficient in terms of fines concentrating degree. In order to satisfy the both conditions of reducing long fiber loss and of increasing flotation reject, several kinds of fractionating promoters were searched and investigated. And high molecular weight cationic polyacrylamide was chosen as a long fiber flocculating and flotation froth-stabilizing agent.
The Effects of Enzymatic Treatment on KOCC
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 34~40
This study was carried out to evaluate the effects of enzymatic treatment on the characteristics of KOCC. Novozym 342 and Pulpzyme HC were used for this purpose. Enzymatic treatment greatly increased the freeness of KOCC and Novozym 342 was more effective. WRV was improved only when KOCC was treated with 0.1% Pulpzyme HC. Pulpzyme HC was more effective to improve the flexibility of fiber(conformability angle) than Novozym 342. Coarseness of fiber was decreased with the enzymatic treatment. Fines content greatly decreased with 0.01% addition of enzymes. Novozym 342 was more effective than Pulpzyme HC for this purpose. Apparent density, tensile index and tear index decreased with enzymatic treatment, but stiffness increased. Especially the decrease of apparent density, tensile index and tear index by the treatment with Novozym 342 was significant than those of Pulpzyme HC. Therefore Novozym 342 will be suitable for the removal of fines and for bulky sheet, otherwise Pulpzyme HC will be good.
Studies on the Application of High-Gloss Plastic Pigment for Paper Coating(II) -Effect of Mixing Ratio of Pigment on the Packing Structure and Optical Properties of Coated Paper-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 41~48
The main objective of this study was to investigate the packing state and optical properties of coated paper prepared with different coating colors by varying the blending ratio of such pigment as clay,
, and plastic pigment. To evaluate the effect of packing state of pigment on the properties of coated paper, the coating thickness, which was theoretically calculated by specific gravity, and packing volume of pigment were used. It was found that there exists close relationship between the coating thickness and surface property of coated paper. For instance, the macro roughness(smoothness) of coated paper is closely related to bulkiness. Plastic pigments used in this research has a high finishing efficiency on the light weight coatings. Especially, hollow sphere pigment was very effective for improving the property of coated paper produced in this test. And when HSP was blended with
the surface property such as smoothness and gloss improved significantly.
Effects of Base Papers Containing Nonwood Pulp on the Properties and Printabilities of Coated Papers(II) -Rice Straw Bleached Kraft Pulp-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 49~57
This study was carried out to investigate the effect of the type of base papers containing rice straw-BKP on the properties and printabilities of coated papers. Also, it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of rice straw-BKP was observed much shorter than those of the wood pulps(Sw-BKP, Hw-BKP). This has effect on physical properties. Therefore, the results of measured physical properties were much lower than those of wood pulps. Also, physical properties tended to increase slightly with the increase of the mixing ratio of Sw-BKP. Opacity of the base paper containing rice straw-BKP, was higher than that of the wood pulps. As the mixing ratio of Sw-BKP increases the opacity tended to decrease. On the other hand, smoothness and roughness to rice straw-BKP were similar with Sw-BKP and its air permeability was lower than those of wood pulps. The optical properties of coated papers containing rice straw-BKP tended to be similar to those of other base papers. The ink receptivity of coated papers containg rice straw-BKP was higher than those of wood pulps and printing gloss was similar to wood pulps. The mixing ratio of Sw-BKP, the ink receptivity and printing gloss of rice straw-BKP were showed no difference irrespective the mixing ratio of Sw-BKP. Meannwhile, amphoteric latex improved the optical properties and printability of coated papers.
Manufacturing of Korean Traditional Handmade Paper with Reduced Fiber Damage(IV) -Effect of Pectinase Treatment on Bast Fiber of Paper Mulberry and Durability of Handmade Paper Under Heat Aging-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 58~65
Use of a pectinase during preparing handmade papers from bast fiber of paper mulberry(Broussonetia kazinoki Sieb.) was investigated in order to decrease cooking chemicals and environmental pollution. For this purpose, four kinds of commercial pectinases, Rapidase LIQ(RLP), Rapidase Press(RP), Rapidase C80L Max(RCM) and Pectinase SS Kyowa(PSK) were used. And the durability of handmade papers before and after pectinase treatment was determined. RP and PSK had higher pectinase activity ad lower cellulase activity. The bast fiber was not defibered when pectinase was used. In order to increase the efficiency of enzymes, the bast fiber were treated ammonium oxalate(AO) or
under mild conditions. The AO pretreatment with those produced by
. The RP treated pulps after mild
cooking of the bast fiber were defibrated more easily than untreated pulp. The handmade paper prepared with the RP treated pulps after mild
cooking has good strength properties such as breaking length and folding endurance. Also, it has higher durability on heat aging, though its brightness was slightly lower than that of untreated paper.
Utilization of Pine Bark(Part 6) -Alkaline Sulfite-Anthraquinone Cooking of Underground Bark and Characterization of the Spent Liquor-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 66~73
Alkaline sulfite-anthraquinone(AS-AQ) cooking process has been applied to unground pine bark. The properties of the spent liquor such as molecular weight distributions, sulfonic equivalent weights, degree of sulfonation, phenolic hydroxyl groups and kaolin dispersing ability have been investigated to evaluate the possibility of using this liquor as concrete additives or binders. In the case of ground bark meal, more than 90% delignification was achieved at the optimal cooking conditions. However, applying these conditions on unground bark the delignification was slightly retarded. The decrease in the degree of delignification may be attributed to less penetration and diffusion of chemicals during the cooking of the bark. Increasing the cooking temperature only by
improved the delignification of the bark and about 90% delignification can be achieved. These results indicate that bark can be used successfully during AS-AQ cooking without any mechanical or physical pretreatment. The properties of lignin or polyphenol sulfonates in the spent liquor after AS-AQ cooking of the bark were compared with Sunflo-R, which is commercial lignosulfonate(CLS) prepared from wood. The weight average molecular weights(Mws) estimated by gel-filteration chromatography was found to be ranging from 1,200~1,800. These are considerably lower than those in CLS. Lignin or polyphenol sulfonates in the spent liquor of bark and CLS have similar degree of sulfonation, but the phenolic hydroxyl group was 1.8 times higher than CLS. Moreover, the dispersing abilities of the spent liquors were better than that of CLS, especially after 0.1% addition to kaolin suspension.
Nitric-Acid Pulping of Municipal Wastepapers and its Spent-Liquor Utilization for Fertilizers(I) -Study on the Nitric-Acid Pulping Conditions of OCC Pulp-
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 74~80
A series of studies on nitric-acid pulping of municipal recycled waste papers were carried out to substitute the bleached chemical pulp imported for producing printing paper as well as to use its solidified spent-liquor as fertilizer. The first experiment was carried out to find the optimum treatment conditions such as pulp consistency, nitric acid charge and temperature in
-alkali pulping process. The results obtained were as follows: 1. Some selective delignification of OCC pulp was conducted by
-alkali process. The higher the temperature and concentration of nitric acid, the lower the pulp yield and kappa number of treated pulp. while its brightness was increased. 2. The higher consistency required the stronger mixing in case of more than 5% pulp. 3. In the laboratory, the suitable
-treating condition seemed to be less than 6% consistency, lower than 500%
charge on pulp and lower than
in cooking temperature. 4. The spent liquor with 1.77% N-content seemed to be slow-release nitrogen fertilizer suitable for agriculture.
Comparison of the Painting and Writing Properties of the Traditional Handmade Papers by Image Analysis
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 81~86
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.
Comparison of the Morphological Properties of the Traditional Handmade Papers Using CLSM
Journal of Korea Technical Association of The Pulp and Paper Industry, volume 32, issue 4, 2000, Pages 87~94
The morphological properties of the traditional handmade papers made in Korea, China and Japan were identified using CLSM(Confocal Laser Scanning Microscope). It was shown that the primary and secondary wall of the Hanji fibers were separated. The lumen of the fibers was not observed. Dochim, a traditional way of Hanji calendering, was turned out to accelerate the separation of the two walls, by which the unique effects of Dochim could be obtained. There were no separation of the two walls in Chinese handmade paper and Japanese handmade paper. Lumen was not observed in Senji fibers but it was observed in Whasi fibers. It was postulated that the morphological properties of the fibers are closely related with the calligraphic writings or drawings properties of handmade papers.