• 보존과학회지
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• 제5권1호
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• pp.94-104
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• 1996

This study was carried on paper mulberry bast fibers, which were cut in the length of it's chip by three kinds. And they cooked by sodium hydroxide (NaOH) and ammonium oxalate (AMOX), and pulping process was studied to inquire some properties of hand made papers. The results were as follows. AMOX pulps had $10\~17\%$ higher than NaOH, but amounts of the residual lignin of it's pulps and residual ash were high, and it surely can't be superior. In the freeness of pulps, AMOX pulps were higher than that of NaOH, but they showed tendency to opposite in view of relation of chip's length kinds. For the AMOX pulps, the physical characteristics test results were higher long fiber pulps than short fiber pulps. Specially, in folding endurance long fiber pulps were a very strong. NaOH pulp's physical characteristics test had shown results that were opposite of there of the AMOX pulps, if the length of the fiber is longer, the strengthts generally decreased. To get the optimum fiber's length according to use of paper and pulping method, they must be fractionate chip's length. The long fibers in NaOH pulps affected the paper quality greatly to length of chips.

• 대한화학회지
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• 제55권1호
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• pp.86-91
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• 2011

수산화나트륨과 과산화 무기산을 사용하여 흑색 액체로부터 수산화 리그닌과 과산화 리그닌을 얻었다. 과산화 리그닌을 10% HCl을 사용하여 가수분해하여 가수분해 리그닌을 얻었다. 카르복실화와 인산화과정을 거쳐 카르복시 리그닌과 인산화 리그닌을 얻었다. 에피클로르히드린을 사용하여 가교 리그닌도 얻었다. 이들 얻어진 리그닌들을 적외선분광법, 열김량분석, 시차열분석법으로 분석 하였다. 이들 얻어진 리그닌의 금속이온 흡착효과를 조사하였다. 과산화 리그닌이 수산화된 리그닌 보다 흡착 능력이 우수하였다.

• Journal of the Korean Wood Science and Technology
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• 제21권3호
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• pp.67-73
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• 1993

This study was attempted to develop the Special Sheet Former for Hanji (Korean Traditional Paper), which could be easily used anyone who has no any special skill, and to evaluate its sheet forming characteristics. The sheet former for Hanji was designed, manufactured and tested its sheet forming features. This former was resulted in superior even basis weights and good formation of sheets without any special technological experiences, but poor consolidation according to the difficulty of web pressing during dewatering process. Sulfomethylated pulping resulted in the superior pulp with high yield and better quality compared to those of alkali and alkali-peroxide pulps. Since the pulp was so bright, there was almost no need additional bleaching.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.169-169
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• 2011

Xylans are polysaccharides present in large amounts in cell walls of land plants. However, during kraft cooking, a high portion of hemicelluloses including xylans are dissolved in the cooking liquor. In the current trend for a more effective utilization of biomass, attention has been paid to the exploitation of xylans as strength-enhancing additives for paper. It is believed that surface xylan adds flexibility to the cell wall/fiber surface, resulting in stronger fiber-fiber joints or greater contact area between the fibers. Accordingly, there is proposal for a new pulping process involving the extraction of xylan prior to pulping, followed by their re-adsorption on the unbleached pulp. A suitable bleaching process should be employed then, which ought to does not only improve the brightness of the pulp, but also remain the effect of the adsorption of xylan on pulp fibers. The objective of this research was to investigate the impact of hydrogen peroxide bleaching on the properties of unbleached hardwood kraft pulp pretreated with birchwood xylan by measuring optical properties (brightness, post color number, opacity) as well as physical properties (tensile index, tearing index, bulk) of handsheets made from the bleached pulp. In the meantime, the influence of process variables of peroxide bleaching including bleaching temperature, time, initial pH and $MgSO_4$ dosage were studied.

• 펄프종이기술
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• 제36권2호
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• pp.33-38
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• 2004

Toner particles used in laser and xerographic printing process is fused on paper surface so strongly that they tend not to detach easily from the recylced paper surface during pulping. Furthermore, the removal efficiency of detached toner particles by conventional screening and flotation process has limitation due to the platy shape and large size of detached toner particles. It has been shown that the removal efficiency of toners in the screening process can be increased by agglomerating the toner particles with fatty alcohol. It is not possible, however, to remove small and platy toner particles by screening process. These small and platy toner particles should be removed by flotation process. In this study the effect of fatty alcohol that used for toner agglomeration on flotation efficiency has been examined. It was shown that flotation efficiency decreased when fatty alcohol was used most probably due to its effect of reducing hydrophobicity of toner particles.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.151-156
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• 2011

• Fibers and Polymers
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• 제7권1호
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• pp.26-29
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• 2006

Samples of kenaf (Hibiscus cannabinus) grown in Malaysia were examined to determine the kraft pulp and paper-making properties of their bast (or bark) fibers. Using kraft pulping process showed that bast fibers were relatively easy to cook resulting good pulp yields in the range of 45-51 %. The bast pulp produced sheets with great density, tear index and dry zero-span breaking length. Kenaf bast fiber is considered promising for production of high-grade printing, writing and specialty papers.

• Journal of the Korean Wood Science and Technology
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• 제44권1호
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• pp.135-146
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• 2016

국내에서는 열기계펄프 생산을 국내산 소나무(Pinus densiflora)만을 사용하고 있다. 가격적 측면에서 장점이 있지만 지속적인 수급이나 피치와 같은 문제점이 내재되어 있기 때문에 주원료를 대체할 수 있는 방안이 강구되어야 한다. 열기계펄프의 원료로서 국내산 소나무를 대체할 수 있는 수종으로 러시아산 가문비(Picea jezoensis), 러시아산 낙엽송(Larix leptolepis), 그리고 미얀마산 대나무(Phyllostachys bambusoides)를 선정하여 열기계펄프 특성을 분석하였다. 이들 원료들은 동일한 조건 하에서 열기계펄프로 제조되었다. 러시아산 낙엽송과 미얀마산 대나무는 펄프화 공정에 부정적인 영향을 미칠 수 있는 추출물 함량이 과량 검출되었다. 러시아산 가문비는 다른 수종들과는 달리 shive와 피치의 함량이 가장 적게 정량되었고, 리파이닝 에너지도 국내산 소나무에 수준으로 매우 적게 소모되었다. 열기계펄프의 백색도면에서는 가문비가 가장 높은 백색도를 나타내어 표백 약품의 절감에 기여할 수 있을 것으로 기대되었다. 결론적으로 러시아산 가문비가 공정 에너지 절감과 펄프 품질 향상 측면에서 국내산 소나무를 대체할 수 있는 가장 우수한 수종인 것으로 나타났다.

• 펄프종이기술
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• 제46권2호
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• pp.1-7
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• 2014

Causticizing calcium carbonate (CCC) is produced as a by-product in the causticization step of the kraft pulping process. It is often calcined in a rotary lime kiln after being dewatered and reused in the causticizing process. But for the China mill, the conventional recycled way is difficult because the CCC is mainly obtained from non-wood pulping materials, which higher silicon content led to serious silicon obstacle. So it is often discarded as solid waste or used in landfill after dewatering and secondary pollution is brought. In order to prevent its secondary pollution, recent years, the CCC is used as a filler in China papermaking industry. In mill trials, the CCC can be used to replace an amount of precipitated calcium carbonate (PCC). Unfortunately, the application scope and dosage of CCC have been limited due to its lower sizing efficiency than PCC. In this study, the reason for the lower sizing efficiency of alkyl ketene dimer (AKD) when CCC was used as a filler was investigated. The results showed that the materials in green liquid, such as insoluble matter in green liquid, silicon and metal ions, were a little influence on the sizing efficiency of AKD. The higher BET and BJH pore volume of the CCC were the main reason for lower sizing efficiency of AKD when it was used as filler.

• Journal of the Korean Wood Science and Technology
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• 제8권3호
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• pp.64-76
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• 1980

Fig. 8 summarizes the present status of high yield pulp production and the directions of research on modification. A thick line indicates pulping process presently in use. As mentioned previously, one kind of modification is to introduce hydrophilic groups onto the pulp. Still unsolved is whether or not the introduction of hydrophilic groups should be restricted to lignin only. Goring (28) reported that middle lamella lignin has fewer phenolic hydroxyl groups than cell wall lignin and suggested that such a difference in the lignin may be useful in the removal of middle lamella lignin. The introduction of hydrophilic groups onto pulp may not be enough to modify high yield pulp. The removal of some portion of carbohydrate may be also necessary from the standpoint of softening of pulp fibers. There is no information at what lignin and carbohydrate, and how much should be removed. The combination with synthetic high polymers may also be important in modifying high yield pulp. Prof. C. Schuerch of the State University of New York who was a visiting professor at the University of Tokyo in 1974, mentioned that the hydrophilicity of lignin would be promoted, if phenolic hydroxyl or carboxyl groups could be introduced into the aromatic nucleus of lignin. If this were possible. this process would also mean a pulp yield of more than 100%. This idea is just one example of the expectation made possible through lignin chemistry. Instead of the introduction of hydrophilic group, the oxidative degradation of aromatic nucleus of lignin may also be useful in promoting the hydrophilicity of pulp. In this case, ozone may be an excellent chemical. However, there are a lot of problems to be solved such as homogeneity of reaction and selectivity of ozone for lignin. The above ideas are summarized in Fig. 9. There are many problems to be solved in the production of an excellent high yield pulp which is comparable to chemical pulp. The information from wood chemistry hopefully will elucidate some of the problems mentioned above.