• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.172-177
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• 1999

Effect of fiber treatment with cellulase (Liftase A40), and with two refining methods (Valley beating and impact refining) on wood fiber and handsheet properties were investigated at three refining levels (300, 400, and 500ml) for two furnishes (NBKP and LBKP). Part of the treated furnishes were classified by 150 mesh screen into fine-free fiber, and fines. Fiber length analysis, WRV, zero-span strength, and other handsheet mechanical properties were compared. The study showed that Liftase A40 lowered the zero-span and the folding endurance of both furnishes (NBKP much more and LBKP much less). Pretreatment with Liftase A 40 followed by refining significantly lowered the fiber length and refining energy to reach to the target freeness. Impact refining, which is done by hitting the fibers vertically with rod at 20% solid content, kept the fiber length increased WRV, and improved handsheet mechanical properties much more than valley beating. Properties of fines from different sources were compared in detail in the study.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.18-23
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• 1999

This study examined the effects of multiple recycling on deinkability and properties of recycled paper from laser computer printout(LCPO). First, alkaline paper with a 20% printed area was disintegrated by TAPPI standard disintegrator. After dewatering , the pulp was followed by flotation, handsheet making, and drying at room temperature, in order. A sequence of printing , disintegrating, flotating , handsheet making and drying was one recycling cycle and this cyclic treatment was repeateed from zero to five times. The residual ink content in recycled handsheets by SEM-EDXA and Py-GC analyseswas increased slightly as recycling number increase. After five cycles of recycling the ISO brightness of recycled handsheets dropped to about 90% of the original brightness. However, it had a gain of 10% in opacity. The most of physical properties of recycled handsheets were decreased as recycling numbers increase except of for tear strength.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.54-59
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• 1999

This study was to quantify fiber distributions in thickness direction of kenaf handsheets as a fiber distribution index (FDI) and to analyze the relationship between FDI and the handsheet properties. The images of fiber distribution in z-direction were obtained by Confocal Laser Scanning Microscope (CLSM) and analyzed by image analysis technique. The proposed FDI had a good correlation with high R2 vlaues with various properties of paper, such as apparent density, scattering coefficient , burst index, tear index, tensile index, and folding endurance. The proposed FDI was shown as a good index to quantify paper properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.67-74
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• 2004

This study was carried out to investigate the characteristics of handsheets made from nonwoody New-Zealand hemp (Phormium tenax) fibers that was not used before in Korea. The results were as follows : 1. Physical properties of bleached phormium fiber were satisfactory for handsheet forming. Specially, tensile strength was improved by adding bleached phormium fiber. 2. Opacity of handsheet with phormium pulp was fine, therefore it can be useful fiber to improve opacity of light-weight printing paper. 3. Filler retention rate was improved when phormium pulp was added, while drainage time was increased. 4. Phormium fiber has good characteristics as pulp for paper manufacture. So it can be valuable non-wood fiber resource if drainage problem is solved.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.153-159
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• 2006

Red algae were used to make bleached pulp, from which paper handsheet samples were made. Red algae consists of rhizoidal filaments, epidermal tissues whose color were reddish, mucous carbohydrates, and other minor elements. Rhizoidal filaments of high brightness were obtained after extracting out mucous carbohydrates, and bleaching the remainder by using bleaching chemicals. The sizes and shapes of several rhizoidal filaments (or red algae pulp) from different red algae species were examined, and their handsheet properties were compared. Transparent and transluscent high density paper samples were made without applying refining process from the red algae pulp. White paper samples with good printability and excellent formation were made. We are developing pilot scale pulping and papermaking facilities at this time.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.8-15
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• 2000

This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, SW-BKP, White ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strehgth properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and White ledger no increase except tear index. In Hobart mixer pre-treatment, HW-BKP and White ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and White ledger were 0.837 mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mm and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.70-70
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• 2000

This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, Sw-BKP, white ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strength properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and white ledger no Increase except tear index. In Hobart mixer pre-treatment, HW-BKP and white ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and white ledger were 0.837mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mn and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.71-77
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• 2014

Despite the ubiquity of electronic media, paper is still the most generally readable carrier of information. Because paper materials are deteriorated by chemical, biological and physical factors over time, there have been major concerns about the decay of large collections of books, publications, old maps, historical artifacts, and written records. Therefore, manufacture of permanent paper has been a highly debated issue in paper conservation research. Through the use of permanent paper, our new records, journals, library books, art works, and all culturally and historically important documents can be preserved. In this study, handsheets were made of mixture of hemp bast fiber produced by soda pulping and HwBKP varying the amount of hemp. Physical, mechanical and optical properties of each handsheet were examined. As the ratio of hemp bast fiber increased, mechanical properties were improved significantly, but opacity decreased. After aging, the optical properties of the handsheets mixed with the hemp bast fiber more decreased than those of the non-mixed handsheet. The more mixture ratio of hemp bast fiber increased, the more decreasing rate of optical properties increased. As a result, it was confirmed that hemp bast fiber is a very promising resource for the manufacturing of permanent paper.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.04a
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• pp.322-323
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• 2008

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.5
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• pp.56-63
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• 2013

In this study, paper mill applicability of two kinds of cotton pulps which have different initial freeness, fiber length and intrinsic fiber strength were investigated. Basic properties such as CED viscosity, fiber length, and crystallinity of major two kinds of cotton pulps were analyzed, and beatability of cotton pulps and physical properties of handsheet made from two kinds of cotton pulps were compared. Laboratory beating was performed at different refining conditions such as refining loads and freenesses. Relationship between beating degree and physical properties of handsheet were compared to seek optimum condition of refining for different cotton pulps application to paper mill.