• 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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• 제46권6호
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• pp.63-70
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• 2014

Part of SB latex in pre-coating color was substituted with newly developed starch-based bio-binder in order to investigate the effect of starch-based bio-binder in pre-coating color on the properties of coating color and coated paper. Smoothness and gloss of coated paper were decreased with the increase of bio-binder substitution ratio. Brightness and whiteness did not show the significant changes, but stiffness was improved with bio-binder. Ink set-off, dry-pick and wet pick were decreased with the increase of bio-binder substitution ratio. In general, when all SB latex is substituted with bio-binder, ink set-off, dry- and wet-pick were deteriorated. However, it was found that if the bio-binder substitution ratio is controlled below 50%, similar qualities with coated paper manufactured by the use of SB latex binder can be obtained.

• 펄프종이기술
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• 제33권3호
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• pp.29-36
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• 2001

This paper was made to evaluate the effect of the blending ration of GCC and No. 1 clay on the printability by investigating the structure of pore such as the pore rate, the number of pores, pore size and distribution of coated paper. The coated structure is mainly depended on the results of correlation between pigment and binder. It means that the structure of the pore occurred is chiefly affected by the blending ratio of GCC and No. 1 clay. This physical properties of the pore have a close relation with ink set-off associated with the drying rate and the penetration in ink into base paper and with printing gloss. Therefore it was needed to find out how the pore structure and the printability will be changed by modifying the blending ratio of GCC and No. 1 clay to vary the pore structure of coated paper. Below are the results of measurement: As the blending ratio of clay going up, water retention, sedimentation volume. smoothness, and paper gloss were increased, but relatively brightness and opacity were decreased. Pore rate was the highest at the blending ratio of No. 1 clay to GCC, 70:30. In this case, average pore radius was also increased. Ink receptivity and K&N ink receptivity were improved with the increase of the blending ratio of GCC, where was, ink setting was vice versa. No difference was observed in the weight of ink, but ink repellance decrease with the decrease of blending ratio of GCC.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2008년도 제33회 펄프종이기술 국제세미나
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• pp.47-70
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• 2008

Cost efficiency is today the primary requirement in the paper and board industry. This has led therefore, to a greater preponderance of products with specifically designed functionality to take account of current industry needs. Continually increasing machine coating speeds together with these new coating colour components have put more emphasis on the importance of the correct rheology and water retention of the coating colours to achieve good runnability and end product quality. In the coating process, some penetration of the aqueous phase, to the base paper or board must occur to anchor the pre-coating to the base or the topcoat to the pre-coat. The aqueous phase acts as a vehicle not only for the binder, but also for the other components. If this water or material penetration is not controlled, there will be excessive material shift from the coating colour to the base, before immobilization of the coating colour will stop this migration. This can result in poor machine runnability, unstable system and uneven coating layer, impacting print quality. The performance of rheology modifiers or thickeners on the coating color have tended to be evaluated by the term, "water retention". This simple term is not sufficient to explain their performance changes during coating. In this paper we are introducing a new concept of "material retention", which takes note of the total composition of the coating colour material and therefore goes beyond the concept of only water retention. Controlled material retention leads to a more uniform z-directional distribution of coating colour components. The changes that can be made to z-directional uniformity will have positive effects on print quality as measured by surface strength, ink setting properties, print gloss, mottling tendency. Optical properties, such as light scattering, whiteness and light fastness delivery should also be improved. Additionally, controlled material retention minimizes changes to the coating colour with time in re-circulation giving less fluctuation in quality in the machine direction since it more closely resembles fresh coating for longer periods. Use of the material retention concept enables paper and board producers to have more stable runnability (i.e. lower process costs), improved end product quality (i.e. better performance of used chemicals) and/or optimized use of coating colour components (i.e. lower total formulation cost)

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.164-165
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• 2021

To prepare the good-adherent and weather-resistant acrylic resin coatings, acrylic resin was prepared by a radical polymerization. Glass transition temperature(Tg) of the acrylic copolymer was fixed at 30℃ and the contents of tertiary amine monomer(DMAEMA) was varied to be 5, 10, 15, 20 wt% respectively. γ-Glycidoxypropyltrimethoxysilane(GPTMS) containing epoxy group was used for curing agents and di-n-butyltindilaurate(DBTDL) was used for drying accelerator. The equivalent ratio of amine to epoxy was 1:1. The prepared coatings exhibited excellent adhesion to various substrates, and various physical properties of the coatings were satisfactory. The gloss retention and color difference were improved at low tertiary amine concentration. The coatings containing 10wt% tertiary amine concentration have especially good weather resistant properties.

• Elastomers and Composites
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• 제45권3호
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• pp.199-205
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• 2010

실내 건축내장재로 medium density fiberboard (MDF)는 널리 사용되는 재료이지만, MDF 합판과 표면재의 바인더로 사용되는 포름알데히드 수지의 유리 포름알데히드와 휘발성 유기화합물의 방산 문제점이 있다. 이를 해결하기위해 본 연구에서는 포름알데히드 흡착성능이 있는 축합형 탄닌을 활용하여 표면재에 적용 하였다. 표면재에 사용되는 수지는 멜라민-포름알데히드 수지와 축합형 탄닌을 사용하여 합성하였으며 반응여부는 FT-IR 스펙트럼으로 확인하였다. 또한 전단응력, 충격강도, 테이프에 의한 접착력 실험, 연필경도, 광택도 그리고 접촉각 등과 같은 표면물성을 측정하였고 미반응 포름알데히드를 분석하기 위하여 유리 포름알데히드 분석법과 소형챔버법이 이용되었다. 결과에 따르면 전단응력과 충격강도는 축합형 탄닌의 함유량이 10 wt.% 일 때 가장 우수한 접착물성을 나타내었지만, 연필경도와 광택도의 경우에는 축합형 탄닌의 함유량이 20 wt.% 일 때 최적의 물성을 발현하였다. 또한 포름알데히드 방산량은 59 ${\mu}g/m^2{\cdot}h$ 로 축합형 탄닌의 첨가에 의해 포름알데히드 방산량을 약 3배 정도 감소 시킬 수 있었다.

• 펄프종이기술
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• 제44권5호
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• pp.32-38
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• 2012

This study was carried out to elucidate the potential in substitution of SB latex with eco-friendly starch based bio-binder as a coating binder. The part of SB latex in coating color of pre- and top layer was substituted with starch based bio-binder in order to evaluate the characteristics of coating color and coated paper, and printability. The viscosity and water retention of coating color were increased by substitution of SB latex with starch based bio-binder. Roughness of coated paper was increased by substitution with starch based bio-binder, although there was not significant changes in roughness when SB latex is used as a binder in pre-coating color. Brightness and whiteness of coated paper were not affected, but opacity and print mottle were improved by substitution with starch based bio-binder. The interesting result observed was that dry-pick did not affected significantly, and ink set-off was improved by starch based bio-binder. It is expected that starch based bio-binder can be commercialized if the systematic further research works are carried out.

• 펄프종이기술
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• 제33권2호
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• pp.41-48
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• 2001

This paper was made to evaluate the effect of the type of latex for coating on the printability by investigating the structure of pore such as the pore fraction, the number of pores, pore size and distribution of coated paper. The coated structure is mainly depend on the results of interaction between pigment and binder. It means that the structure of pore formed is chiefly affected by the type of latex. This physical properties of pore have a close relation with ink set-off associated with the drying rate, the speed of penetration of ink into base paper and printing gloss. Therefore it was necessary to find out the relationship between pore structure and the performance of printability by modifying the type of latex to vary the pore structure of coated paper. Acrylic latex was superior to S/B latex in the sedimentation volume, compressibility, smoothness, pore fraction and its number, the weight of transferred ink onto the coated paper and ink repellance. In contrast, water retention and ink setting were not good. in the comparison of anionic and amphoteric latex, amphoteric latex showed better performance in the thickness, smoothness, pore fraction and its number, pore size, the weight of ink transmitted and K&N ink receptivity, etc.

• 펄프종이기술
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• 제41권3호
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• pp.1-7
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• 2009

Talc as a coating pigment has been developed in order to replace GCC and clay for matte grade and has received much attention due to various advantages including good gravure printability. In order to elucidate the effects of talc on gravure printability, model papers were produced with three kinds of coating talc whose particle size and brightness are different. Physical properties related to surface and structure and the gravure printability of the sample were tested. Coating color with talc showed lower viscosity than that with clay. For both matte and art grades, talc tended to give lower gloss than day. The smaller the particle size of talc, the better properties in the coating color viscosity and water retention. When the particle size of talc was small enough, the surface roughness of the coated paper produced with talc was similar to that with clay while larger talcs produced rougher surface than clay. On top of that, application of talc improved compressibility and gravure printability of coated paper.

• 펄프종이기술
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• 제41권3호
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• pp.8-12
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• 2009

According to a previous study, talc as a coating pigment can improve the viscosity and the water retention of coating color, the compressibility of coating layer, and hence gravure printability. Talc is also well known for its larger particle size than other pigments, which implies that less binder may be need due to its smaller specific surface area. This study investigated the possibility of reducing binder content for matte grade paper. Coating color was prepared with the Cotalc-2000, which showed the best properties in the previous study. The binder content was varied and the effect of binder content on the physical properties of coated paper and the gravure printability was investigated. It was shown that binder content could be reduced when talc was used as a coating pigment. The reduction in binder content did not influence gloss, roughness and the print density of coated paper but showed improvement in paper porosity, compressibility and missing dot.