• Journal of Forest and Environmental Science
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• 제18권1호
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• pp.97-105
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• 2001

The main objective of this study was to investigate effects of pigment mixed with different ratio on the double coated paper. Mineral pigments such as clay and ground calcium carbonate(GCC) as well as hollow sphere plastic pigment were used to evaluate the physical, optical properties and printabilities of double coated paper. The physical properties such as gloss and smoothness, and the printability(ink gloss) of double coated paper were measured to evaluate the effects of the bottom layer on improving the properties of top layer. The data indicated that the usage of hollow sphere plastic pigment for the bottom layer coating improved the surface properties of double coated paper, and that ink gloss was significantly influenced by the structure of bottom layer even when hollow sphere plastic pigment was used for the bottom layer coating.

• 현장농수산연구지
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• 제12권1호
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• pp.53-62
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• 2010

사과 홍로품종에서 칼슘이 코팅된 포장지의 수확 후 저장기간 연장에 미치는 효과를 알아보기 위해 과실을 포장한 후 저장 조건을 달리하여 과실의 품질, 감모율과 부패과율, 이산화탄소와 에틸렌 발생량을 조사한 결과는 다음과 같다. 칼슘 포장지는 다른 포장지에 비하여 당도(가용성고형물)가 상온저장(20~25℃)에서 4주후 약간 높았으며 저온저장(0~1℃)에서는 14주 후 높았다. 과실 경도는 상온저장에서 4주후까지 저온저장에서 14주까지 유지되었다. 총산함량 및 과피의 적색도(Hunter a값)는 오히려 감소되는 경향을 보였다. 감모율은 왁스 및 칼슘 포장지는 다른 처리에 비하여 낮아 상품성 과실이 많게 나타났으나, 저온저장에서는 큰 차이를 인정할 수 없었다. 부패과율과 이산화탄소 발생량은 칼슘포장지가 가장 낮았다. 에틸렌 발생량은 포장지 종류, 저장조건에 따라 차이는 없었다.

• 펄프종이기술
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• 제44권3호
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• pp.1-8
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• 2012

The effects of several factors including organic pigment blending and calending conditions on the surface and optical properties of coated paper were investigated. When clay and calcium carbonate are blended in the ratio of 7 to 3, highest smoothness and relative sediment volume were obtained. When organic pigments were added to the mixture of clay and calcium carbonate, the relative sediment volume did not changed significantly. However, when organic pigments were added to calcium carbonate, sheet gloss and smoothness were improved, and showed the better results than that obtained from the mixture of organic pigment and clay. When organic pigment is blended with clay, the particles of organic pigment are buried in the packing structure of coating layer. However, the particle shape of calcium carbonate is quite different from that of clay, and the aspect ratio of calcium carbonate is similar to that of organic pigment. Thus organic pigment particles are not buried and improved effectively the physical characteristics of coating layer. When the hollow sphere pigment was blended, opacity and sheet gloss were improved significantly. Even though the coating color applied was reduced, the similar level of opacity was maintained. Also, if particle size and void volume are increased, gloss is improved, because coating layer is easily transformed in calendering. Therefore, even though lower pressure was applied during calendering, the smoothness of surface of coating layer was improved, and the decrease of void volume in coating layer was reduced, and the quality of coated sheet can be improved.

• 펄프종이기술
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• 제44권4호
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• pp.91-98
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• 2012

This study was carried out in order to evaluate the effects of ultra fine precipitated calcium carbonate (UFPCC) on properties of coating color, coated paper and off-set printability. It was found that blending of UFPCC increased the low-shear viscosity and water retention of coating color. The smaller the particle size, the more significant the effect of it. When the blending ratio of UFPCC was increased, brightness, whiteness and opacity of the coated paper were improved, while paper gloss was decreased due to the increase in roughness. When the UFPCC with the average particle size of $0.12{\mu}m$ was used, the ink receptivity during off-set printing was improved while print gloss was maintained or a little decreased. It was also observed that the dry-pick and wet-pick strength of coated paper were improved by the use of UFPCC. In conclusion, it is possible to produce the low gloss matt paper with the use of UFPCC since it could improve the optical properties and ink receptivity of coated paper.

• 생물환경조절학회지
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• 제17권4호
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• pp.312-318
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• 2008

추황배'에서 칼슘이 코팅된 이중봉지를 이용하여 봉지 물성, 미기상, 과실로의 칼슘 축적 및 과실품질에 미치는 영향을 조사하였다. 칼슘처리봉지는 관행봉지와 비교하여 투광율, 인장강도, 온도 및 상대습도는 차이가 없었다. 그러나 칼슘처리 봉지의 과피내 칼슘 함량은 만개 후 65일 부터 160일 까지 관행 봉지보다 현저히 많았다. 그러나 과육에서는 160일에서만 증가되었다. 칼슘처리 농도별 과실내 칼슘함량은 과피에서는 황색이중봉지 12%, 신문이중봉지 9, 12%에서 높았고 과육에서는 황색이중봉지 3%, 신문이중봉지 6, 9, 12%에서 현저히 높았다. 방사성 등위원소를 이용한 과피 및 과실로의 칼슘 축적은 과피는 처리 후 60시간까지 증가였으나 과육 조직은 무처리 과피와 큰 차이는 없었다. 수확시 과실경도는 황색이중봉지는 농도 간 큰 차이는 없었으나, 칼슘 6, 12%처리 신문이중봉지에서 현저한 차이를 보였다. 가용성고형물은 칼슘 6, 9%처리 황색이중봉지와 3, 6, 9%처리 신문이중봉지에서 현저히 높았다. 그러나 봉지내 칼슘처리에 따른 과중 및 과피색 변화는 차이가 없었다.

• 펄프종이기술
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• 제29권1호
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• pp.26-35
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• 1997

A study was carried out to investigate such optical properties of coated papers as brightness, opacity and gloss affected by the coating pigment composition and coat weight using clay, ground calcium carbonate, precipitated calcium carbonate, and plastic pigment as pigments. The effects of drying methods and supercalendering on optical properties were also evaluated. Gloss increased abruptly while brightness and opacity decreased slightly by supercalendering due to surface smoothing and consolidating effects of the coating layers. Optical properties changed little by drying methods. Pigment composition showed significant influences on optical properties. Brightness of coated papers decreased or increased linearly as the coat weight was increased depending on the pigment composition, while opacity increased linearly for all formulations. Gloss increased abruptly at low coat weights for all formulations and approached a plateau value at coat weight of 15-20g/$m^2$. Third order polynomial regression equations relating the coat weight with gloss have been derived and tabulated.

• 펄프종이기술
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• 제31권3호
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• pp.26-34
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• 1999

This paper was intended to find out the relationship between optical and interior properties of coated paper and printability with the variation of particle size of ground calcium carbonate(GCC) by using Mercury Porosimeter, and to find out the pore properties of coated paper as well. The viscosity and water retention of coating color was increased and smothness, sheet gloss and porosity of coated paper were improved as the particle size of GCC was decreased. However, there was no difference in opacity and brightness of coated paper. The pore volume of coated paper was decreased, but the number of pores was drastically increased according to the decrease of the particle size of GCC. The weight of ink transferred into coated paper was increased in proportion to pore volume of coated paper. However, the weight of damping water and ink induced toward coated paper was slightly increased. Ink setting was accelerated printing gloss was not changed. Therefore, optical and interior properties of coated paper seemed to be affected by the pore property of coated paper and printability was also affected by it.

• 펄프종이기술
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• 제30권2호
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• pp.62-73
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• 1998

The aim of this work was to investigate the effects of pigment composition on the calendering response and structure of the coated paper. Calendering response of the coated paper was determined from the gloss values of the uncalendered and calendered coated papers, and the relationship between gloss and coating structure was discussed. The surface and cross section of the coating layer was observed using a scanning electron microscope to examine the coating structure. Coating layers were hardened in epoxy resin and polished with carbimet paper disc for preparing SEM samples. Maximum calendering response was obtained for the coated paper prepared from 80pph of clay and 20pph of ground calcium carbonate (GCC) as pigments. Photomicrographs of the surface and cross section of the coating layer show that clay tends to form dense coating structure, while GCC tends to form bulky coating layer.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2003년도 춘계학술발표논문집
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• pp.70-79
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• 2003

Paper coating can give smoothness surface and good printability to uncoated paper. Macro roughness of base paper would be decreasing its groove and grit in view of side. Nevertheless its improving effect for paper, some kind of problem is showing in the fine coated paper. Especially, back trap mottle is one of serious problems in printing with fine coated paper. Printers can not adjust conditions to overcome the problem. Also large amounts of paper can be rejected. There are many factors that influence back trap mottle. However it is not clear what the important parameters are in back trap mottle. Back trap mottle has some relationship with ink setting but good guidelines are not clear. Back trap mottle has been linked to non-uniform ink setting. We do not know how much variation in setting we can tolerate. Other mottle issues such as micro-picking and ink refusal are still common. This paper was prepared to identify correlation with ink setting and delta ink density obtained from experiment and then tried to find out some relationships with ink setting and back trap mottle. Basically fine calcium carbonate and ciay was used for main components and coarse calcium carbonate was mixed in two fine pigments to change its porosity and ink acceptance. Micro ink tack force at KRK printing tester was adapted to measure ink setting rate. KRK units were used for back trap mottle simulation and two printed samples were prepared to check delta ink density. Clay base coating has more fast ink setting time than calcium carbonate's though smoothness of clay was better than calcium carbonate. It could be explained by that clay has finer pore in its coating than calcium carbonate. DID(delta ink density) has shown a good correlation with ink setting time from micro ink tack. The total pore volume of coating layer did not match with ink setting and DID. From the results we might conclude coating that has fine pore size around 0.05 ${\mu}m$ can be exposed to high possibility of back trap mottle.

• 펄프종이기술
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• 제32권3호
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• pp.32-38
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• 2000

This study was carried out to determine the effect of the type of plastic pigment on the coat-ing structure and printability of coated paper. Three kinds of plastic pigments(solid-bead type binder type and hollow type) were used for hti purpose. IN this research it was observed that particle shape and structure of plastic pigment had influenced the rheology of coating color the state of packing and the properties of coated paper. Inorganic pigments used in this research were platelike kaolin clay and rhombic calcium carbonate. Three kinds of plastic pigments were blended with two inorganic pigments respec-tively. The combination of pigments were carried out(1) to determined the effect of particle structure of plastic pigment on the state of dispersion of coating color(2) to observe the effect of calendering temperature on the property of coated paper prepared with different plastic pigments. The data indicated that binder and hollow type plastic pigment gave the best results in improving the properties of coated paper such as paper gloss opacity and air pet-meability.