JAPAN TAPPI JOURNAL
Online ISSN : 1881-1000
Print ISSN : 0022-815X
ISSN-L : 0022-815X
Volume 45, Issue 12
Displaying 1-11 of 11 articles from this issue
  • Ikuo Momohara, Yuji Matsumoto
    1991 Volume 45 Issue 12 Pages 1297-1315
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Recent advances in the knowledge of ligninolytic enzyme system and recent trial to apply biological system to pulping and bleaching process are reviewed. Although a remarkable progress in the enzymology of lignin biodegradation was achieved in these ten years, the application of ligninolytic system to pulping and bleaching is not very successuful. Enzymatic degradation of carbohydrate, on the other hand, has been found to be useful for bleaching and fiber modification.
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  • Hidesato Shimoto, Masaki Sharyo, Taisuke Kiriyama, Hiromichi Sakaguchi
    1991 Volume 45 Issue 12 Pages 1316-1334
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Industrial enzymes have been used in numerous industrial applications for many years as a very effective natural catalyst without affecting the environment. Such catalytic power with its high specificity and reaction under mild conditions has been investigated in the area of pulp and paper and some of the applications have been successfully introduced to the real production line.
    Here industrial enzymes and the possibilities of their application in this field are introduced based on the information obtained from literature and patents, as well as from authors' application work.
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  • Mitsuhiro Sano
    1991 Volume 45 Issue 12 Pages 1335-1340
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Paper damping material made of paperbord and viscoelastic polymer has remarkable damping capacity. Particularly, combination of recycled paper and viscoelastic polymer shows superior ability. This damping material is useful not only to make good use of forest resources but also to support comfortable life.
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  • Takeshi Matsui, Akito Hamano
    1991 Volume 45 Issue 12 Pages 1341-1347
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Voids-containing synthetic paper has similar properties of natural paper: lightness, softness, etc, due to containing a large number of fine voids made in stretching process. These are useful for handling and printing. At the same time it is excellent in water resistance, dimensional stability due to moisture adsorption, surface smoothness, etc.
    Therefore, practical uses of it have been developed in recent years as base material for recording paper, etc.
    However, voids-containing synthetic paper has some disadvantages: inferior in stiffness, surface strength and productivity than those of other film-base synthetic paper. Multi-layer filming process is applicable to these problems. Mor over, it is necessary to give proper surface treatments for printing, transfering, copying and so on.
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  • Seikichi Kobayashi, Akihumi Hatta
    1991 Volume 45 Issue 12 Pages 1348-1362
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    The stock preparation refining is considered the most important stage in paper making process. Not only it affects runability of paper machine but it determines quality of paper. And it influences furnish composition and energy consumption which directly influence production cost. The Conflo refiner have a shallow cone angle and short cone. These features ensure long stock retention time inside of refining zone and stable gap clearance. As a result, fibers get gentle, homogeneous treatment which cause a better tear-tensile combination, or a better tensile strength at the same freeness. The Conflo refiner can also keep lower idling power by virtue of increasing effective refining surface area with minimum increase in outer diameter of fillings.
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  • Methodology and Practice of Gene Manupulation Technique
    Atsushi Sawatari, Shinya Kawai
    1991 Volume 45 Issue 12 Pages 1363-1374
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Methods and practice of gene manupulation technique were explained for the production of human insulin. The DNA synthesizing and DNA sequencing were outlined with a few examples. Furthermore, peculiarity in studying gene technology was also described.
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  • [in Japanese]
    1991 Volume 45 Issue 12 Pages 1375
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
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  • Tea-Jin EOM, Say-Kyoun OW
    1991 Volume 45 Issue 12 Pages 1377-1382
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    A new deinking method for old news paper was developed by using commercially available cellulase. About 300 g of old news paper was defibered at 4% pulp consistency by batch type pulper in the enzymeadded water in which pH was controlled at 4.7. And then the suspension was transferred to a laboratory floatation system. The following results were obtained with the deinked pulp from the above-described process.
    (1) Handsheet from the DIP showed a satisfactory level of brightness.
    (2) Defibering time was reduced significantly, compared to conventional method.
    (3) The Canadian standard freeness showed a reduced value for the DIP compared with that from the conventional method. Consequently, an increase in sheet strength was obtained with handsheet from the DIP.
    (4) During the defibering and floatating process by this enzymatic technique, no other additives than enzyme and buffer were required, such as NaOH, water glass, synthetic displector, carboxylic acid soap, hydrogen peroxide and DTPA. Therefore, the substantial reduction in operation cost and treating cost with the effluent liquor are estimated by adopting this enzymatic method.
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  • Effect of depression of color reversion in mechanical pulps by treatment of crude enzyme from Coriolus versicolor and Phanerchaete chrysosporium
    Tamiharu Yamashita, Uji Kage, Sanro Tachibana, Masashi Sumimoto, Kihac ...
    1991 Volume 45 Issue 12 Pages 1383-1391
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Pre-treatment of unbleaced thermomechanical pulp and unbleached groundwood pulp with extracellular crude enzyme solutions from Phanerochaete chrysosporium and Coriolus versicolor, respectively, belonging to white-rot fungi followed by alkaline hydrogen peroxide bleaching gave a remarkable effect on depression of heat-induced color reversion of thermomechanical pulp (TMP) and groundwood pulp (GP), respectively. The effect of depression of heat-induced color reversion by treatment of unbleached TMP with an extracellular crude enzyme solution from P. chrysosporium seems to be related to the pH value in the culture solution. The color reversion was greatly suppressed when the culture solution have lower pH value, especially under pH 4. 6. This suggests that the enzyme from P. chrysosporium responsible for depression of the color reversion is a kind of inducible enzyme by decrease in pH value in the culture solution during incubation. And furthermore, the enzyme responsible for depression of the color reversion was found to be strongly inhibited by heat treatment or by addition of sodium cyanide.
    Furthermore, pre-treatment of unbleached GP with an extracellular crude enzyme solution from C. versicolor, followed by hydrogen peroxide bleaching was found to be very effective to the depression of light-induced color reversion of GP. However, no effect of depression of light-induced color reversion was observed by the treatments of both, GP and TMP with the extracellular crude enzyme solution from P. cioysosporium. This suggests that TMP and GP have some different chromophores contributing to the light-induced color reversion. Based on the results of the reactivity between a model compound and extracellular crude enzymes from C. versicolor, the enzyme responsible for depression of light-induced color revesion of TMP is a kind of oxide -reductase because reduction products as well as oxidation products are recognized in the reaction products.
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  • Pulping of softwoods with acetic acid-water-phenols system
    Naoshi Kaneko, Yoshihiro Sano, Takashi Sasaya, Jyun Otani
    1991 Volume 45 Issue 12 Pages 1392-1399
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
    Acetic acid-water and acetic acid-water-phenols systems were investigated as new solvents for solvent pulping of softwoods.
    Todomatsu (Abies sachalinensis Masters) was delignified readily in 70-90% aqueous acetic acid with or without phenols as delignification accelerants at 170-180t. Karamatsu (Larix leptolepis Gord) was very difficult to delignify under the conditions without phenols, and it yielded pulps with Klason lignin content of over 15%. But the delignification of Karamatsu was improved considerably by cooking with aqueous acetic acid containing phenols. More than 85% of p-cresol as the phenols were recovered respectively from the waste liquors of todomatsu and karamatsu.
    Strength properties of the pulps were comparable to those of softwood kraft pulps except for tear factor. Acetic acid lignins were separated in greater yields from the waste liquors, but yields of sugar products were lower. Acetic acid lignins of AWL-1 were found to be useful for chemicals because of the higher contents of phenolic hydroxyl groups.
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  • 1991 Volume 45 Issue 12 Pages 1400-1407
    Published: December 01, 1991
    Released on J-STAGE: October 27, 2010
    JOURNAL FREE ACCESS
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