• 펄프종이기술
• /
• 제40권1호
• /
• pp.1-8
• /
• 2008

It is essential to use base papers having proper surface characteristics in coating operation for improving coated paper quality and coater runnability. To fulfill these purposes, surface sizing of coating base stock with oxidized starch is commonly practiced. Use of cationic starch for surface sizing improves coated paper quality since cationic starch penetrates less into paper structure. The immediate objective of this study was to examine the influence of surface sizing with starch solutions containing cationic polymers on the rheology of coating colors and the effect on physical properties of coated papers. Changes of rheological characteristics of coating colors placed on the plastic substrate surface sized with cationic and anionic starch were determined. Results of rheological test showed that cationic polymer surface sizing agent increased electrostatic interaction with coating colors and increased storage modulus. This new technology of using cationic polymer as surface sizing additive was considered to be advantageous for base papers at low basis weights since it would improve the coverage and optical properties of coated papers.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
• /
• pp.19-29
• /
• 2006

Drying is the least developed of all unit operations of paper and board manufacture. While groundbreaking developments were Introduced during the several past decades in forming, pressing and calendering, no radical changes occurred in drying. The cylinder-drying technology is now more than 200 years old and, while it was subject to many incremental improvements, many of its inherent problems persist. We believe that conventional drying is now approaching the end of its life and the industry is ready for a major breakthrough in drying. Indeed several innovative technologies already exist at various stages of development or commercialization. In general, the novel drying technologies are striving to increase the drying rate, improve the product quality and boost the energy efficiency of drying. A novel, drying method, $Papridry^{TM}$, which combines conductive and convective heat transfer to obtain very high drying rates, is at an advanced stage of development at Paprican. The results obtained when drying printing paper ana board on a self-standing pilot $Papridry^{TM}$ machine and on the pilot paper machine equipped with a tandem of two $Papridry^{TM}$ units demonstrate both, the high drying rate and improved product quality achieved by using this drying method. A mathematical model of this operation has been developed and the software compiled with this model was used to calculate the effect of installing a $Papridry^{TM}$ unit into an existing dryer section. The model also allows to calculate the z-direction distribution of moisture and temperature at various points of the dryer section.

• 한국염색가공학회지
• /
• 제19권2호
• /
• pp.24-31
• /
• 2007

This paper addresses factors of line image quality on grain leather printed via inkjet printer. Lines were printed onto coated leather media, and line width, edge blurriness, and edge raggedness were evaluated for line image quality. Various factors influenced to wetting and capillary wicking were studied and found out that wicking through capillary between fibers causes significant feathering on leather surface similar with pulp capillary in copy Paper. Polyurethane and acrylic resin coating resulted good image qualify by reducing capillary wicking. The mixture of polyurethane and acrylic resin applied on grain leather satisfied with both image quality and surface hand. $AllWrite^{TM}$ ink brought best results of image quality, comparing with $VeraPrint^{TM}$ ink and $JetWrite^{TM}$ ink.

• 동아시아식생활학회지
• /
• 제17권2호
• /
• pp.227-233
• /
• 2007

The purpose of this research was to study the effects of the feeding of dietary citrus byproducts on the physicochemical properties and palatability of Hanwoo rump (HR). The samples for experimental samples consisted of the HR not fed without citrus byproducts pulp (CBP-0) and the HR rump fed with citrus byproducts pulp during the fattening period (CBP-1). The control (CBP-0) HR rump was fed by general practical feeding (roughages and concentrates were fed separately), while the CBP-1 was fed in the same manners as CBP-0 until 17 months but with citrus byproducts then fed fer the next 10 months. There were no significant differences in the $L^*$ (tightness), $a^*$ (redness) and $b^*$ (yellowness) of the HR between the CBP-0 and CBP-1 fed groups. There were no significant differences in the pH, VBN content and EDA between the samples, but the TBARS value of the CBP-1 fed group was lower than that of the CBP-0 fed group (p<0.05). There were no significant differences in the water holding capacity, freezing loss, thawing loss, boiling and roasting logs between the CBP-0 and CBP-1 fed groups. There were no significant differences in the hardness, cohesiveness, chewiness and shear force between the samples, but the springiness of the CBP-1 fed group was higher than that of the CBP-0 fed group (p<0.05). There were no significant differences in the sensory scores for the roasted beef between the CBP-0 and CBP-1 fed groups. There were no significant differences in the taste, flavor, juiciness and palatability of roasted beef the between samples, but the tenderness of the CBP-1 fed group was superior to that of the CBP-0 fed group.

• 펄프종이기술
• /
• 제45권6호
• /
• pp.17-23
• /
• 2013

The reduction of metal ion from the cotton linter for the preparation of NMMO (N-methylmorpholine N-oxide)-based dissolving pulp was investigated. The NMMO-based dissolving pulp was usually used for the manufacture of high quality fabrics, and need to have high alpha cellulose content and high brightness. NMMO, which is environmentally friendly, and reusable after recovering process, is very sensitive to the metal ions such as Cu, Fe, Mg, and Cr. Electron beam, sulfuric acid, acetic acid, and ozone treatment before bleaching were used and the concentration changes of the metal ions were compared to that of EDTA, a chelating agent. It was found that both acid treatments (sulfuric and acetic acid) were very effective and comparable to EDTA treatment at the same dosage in metal ion reduction, but electron beam and ozone treatment were not. The sulfuric acid treatment turned out to be effective in metal ion reduction, and most inexpensive.

• 펄프종이기술
• /
• 제41권1호
• /
• pp.30-36
• /
• 2009

Cracking of scored or creased lines on boards is a serious problem in converting process of corrugated fiberboard. It is important to reduce the possibility of score crack in advance by controlling the related quality factors of linerboard. To find out the key properties affecting score crack, we carried out the correlation analysis between score crack and physical properties of linerboards. Score crack was evaluated by visual rating on surface crack after folding a linerboard using laboratory folding resistance tester. Thickness of linerboard was the most important factor to score crack. The critical limits of thickness and strain can be determined by correlation analysis for reducing the possibility of score crack.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2001년도 추계학술발표논문집
• /
• pp.42-42
• /
• 2001

The rate of coating consolidation influences the operation of several coating methods and the final quality of the coating layer. The rate of coating consolidation is characterized with a dynamic gloss meter at short times for a thin coating layer applied to the base sheet of interest. During the coating consolidation process, the laser gloss meter response curve exhibits two critical turning points that indicate the two coating immobilization points defined by the traditional methods. Five base sheets with several different coating suspensions are characterized. A model is proposed to estimate the rate of consolidation based on physical properties of the coating suspension, the base paper, and the liquid phase of the coating. The paper properties, especially the contact angle, are found to be an important factor in determining rate of consolidation. The model predicts the correct trends for the different coating suspensions and base sheets. The test method, along the model, can be used to determine the filtercake resistance of the coating layer for a thin and rapidly formed filtercake.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2002년도 추계학술발표논문집
• /
• pp.36-46
• /
• 2002

The accurate characterization of paper structure may provide critical information for ideal selection of raw materials and papermaking processes as well as for predicting the behavior and the quality of final paper products. In this study, local paper structure and the relationship among the structural parameters, thickness, grammage, apparent density and surface roughness of various handsheet and commercial paper samples were evaluated by using recently developed methods. A new concept of surface roughness was also introduced. The results demonstrate that there is significant overestimation in the measured thickness when using the conventional caliper method that originates from the surface roughness and poor paper formation. A novel non-contact thickness tester, referred to as the twin laser profilometer(TLP), provided results that were not subject to these artifacts and thus provided the local intrinsic thickness and consequently the local intrinsic apparent density.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2004년도 춘계학술발표논문집
• /
• pp.56-65
• /
• 2004

The Asia Pacific papermaking giants are China, Japan and Korea followed by Indonesia. The strong trends in recent years have been the move to alkaline/neutral sizing which has assisted the move from kaolin and talc as the major filler minerals to ground calcium carbonate and precipitated calcium carbonate. Kaolin remains important as a constituent in many coating formulations and Chinese-sourced talc, due to its brightness and price will remain important especially in paper filler minerals. The need for ever increasing printing surface quality and continuing efforts by the paper manufacturers to keep costs under control will ensure minerals in papermaking will continue to be a dynamic subject in the years ahead.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2003년도 추계학술발표논문집
• /
• pp.139-147
• /
• 2003

Coater runnability of the paper coating and final product properties can be affected by the immobilization of coating color and the dewatering into the base paper. During the dewatering, the rheological properties and solids content of a coating are dramatically changed. For the purpose of obtaining better coater runnability and high quality of coater paper many papermakers are trying to improve the water retention of paper coatings by using some additives such as thickener and co-binder. In this study, we tried to investigate the rheological properties and the immobilization point of coatings with immobilization cell during the dewatering of coatings.