• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.425-430
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• 2002

The needs of the times, a cement plays an important roll in the materials field. So, in this research we would like to study on the properties of Photocatalytic Cement for waste gas reduction. The fundamental phenomena of the Photocatalytic Cement were observed by the NOx Analyzer, Bonding strength, SEM, Flow and Surface hardness(Pencil tester). As a result of this study, the Photocatalytic Cement used Photocatalytic powder, admixture and other materials can obtain its physical properties, also photocatalytic efficiency. If we have added a various experiment, we could have to develop the Photocatalytic Cement.

• 한국표면공학회지
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• 제28권5호
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• pp.289-299
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• 1995

The effects of phosphate coating have been studied on physical properties and corrosion resistance of painted aluminum alloy sheet for automobile body. The physical properties (surface roughness, paint adhesion, impact resistance and pencil hardness) and corrosion resistance(cyclic corrosion and filiform corrosion) were investigated. Phosphate coatings enhanced the physical properties of painted Al alloy sheet, especially paint adhesion after the 240hours water immersion test. Phosphate coating also markedly improved the resistance for cyclic corrosion and filiform corrosion of painted cold rolled steel and Zn-Ni plated steel sheet as well as painted Al alloy sheet. The corrosion resistance of painted Al sheets was varied with the concentration of free fluoride ion and metal additives like Ni and Mn in the phosphating bath. A maximum corrosion resistance was obtained at about 300ppm of fluoride ion and additives of Ni and Mn obviously increased the corrosion resistance of painted specimens.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.265-270
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• 2001

Nowadays, like any other areas we have asked that the concrete would get more and more properties to increase there performance. So, in this research we are intended to develop the Photocatalytic Concrete which is one of the High Performance Concrete with waste gas reduction and self-cleaning. The fundamental phenomena of the Photocatalytic Concrete were observed by the residue water-weight, SEM, flow and surface hardness(Pencil tester). As a result of this study, the Photocatalytic Concrete used Photocatalytic powder, OPC admixture and other materials can obtain its properties, also photocatalytic efficiency. Last of all, we are convinced of the Photocatalytic Concrete possibility and make an effort to develop its properties added a various study.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.575-580
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• 2002

The most recent, like any other field we have requested that the concrete would increase more a performance. So, in this research we are intended to study on the property of Photocatalytic Concrete which is one of the High Performance Concrete. The fundamental phenomena of the Photocatalytic Concrete were observed by the NOx Analyzer, Bonding strength, SEM, Flow and Surface hardness(Pencil tester). As a result of this study, the Photocatalytic Concrete used Photocatalytic powder, admixture and other materials can obtain its properties, also photocatalytic efficiency(NOx reduction). Also, we have convinced of the Photocatalytic Concrete possibility and put on a spurt to improve its properties added a various experiment.

• 한국인쇄학회지
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• 제26권1호
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• pp.73-85
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• 2008

We have manufactured a photoresist which has excellent dispersity and good applying property due to 330cps of viscosity for environment-friendly and economical maskless screen plate making. And the photoresist applied on the screen stretched was exposed without mask by beam projector with CRT light source. Then it was developed by air spray with $1.7kgf/cm^2$ of injection pressure. The pencil hardness and solvent resistance of curing photoresist film were worse than those of conventional photoresist film and the maximum resolution of line image formed by maskless screen plate making was 0.5 mm since the exposure system for maskless plate making has weak light intensity and the diffusion of light. But we could obtain maskless screen plate which has sharp edges of line image and confirm a possibility of dry development process by air spray method.

• Journal of the Korean Wood Science and Technology
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• 제32권6호
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• pp.23-35
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• 2004

The goal of study was to investigate the influence of the acrylated urethane oligomer on mechanical properties, the chemical resistance and thermal resistance of the UV curable urethane acrylate coatings for fancy veneer overlayed plywood flooring. The pencil hardness and abrasion resistance of the coated fancy veneer overlayed plywood floorings increased with increasing the acrylate functionality of the acrylated urethane oligomer. In the case of the UV cured film containing hexa-functional acrylated aliphatic urethane oligomer, high discoloration of the coated fancy veneer overlayed plywood flooring was observed near the cracks at the beginning of the chemical treatment. In this study, it was found that the degradation of the UV cured film caused by an alkaline reagent was higher than that of the UV cured film caused by an acidic treatment.

• 폴리머
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• 제37권5호
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• pp.587-591
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• 2013

Poly(3,4-ethylenedioxythiophene)(PEDOT)은 높은 전기 전도도, 광학적 투과성 및 좋은 화학적 안정성을 가지고 있는 반면 낮은 물리화학적 물성을 가지고 있다. 본 연구의 목적으로 PEDOT의 내용제성 및 필름경도와 같은 물리화학적 특성을 향상시키고자 하였다. 음이온성 수성폴리우레탄(WPU)이 가지는 카르복실기는 아지리딘 존재 하에서 효과적인 가교반응이 일어나 물리화학적 특성이 개선된 WPU/PEDOT 혼성 전도성 박막을 제조할 수 있다. 다양한 WPU 및 고형분 함량별로 WPU/PEDOT 유기-유기 혼성 박막을 제조하여 전기적/물리화학적 특성을 비교하였다. 고형분 함량이 증가할수록 투과율과 표면저항은 감소하였다. WPU/PEDOT 혼성 전도성 박막의 연필경도와 내용제성이 WPU가 가지는 카르복실기의 가교반응에 인해 효과적으로 증가하였다.

• 접착 및 계면
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• 제13권1호
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• pp.38-44
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• 2012

본 연구는 왁스를 함유한 자외선 경화형 코팅제의 경화 물성, 표면 모폴로지, 코팅 표면 물성을 Photo-DSC, SEM, 진자경도, 연필경도 및 광택도를 이용하여 평가하였으며, 특히 왁스의 종류(파라핀 왁스, PE 왁스)에 따른 제반 코팅 물성을 조사하였다. 그 결과 왁스의 종류는 코팅 도막의 광택도와 표면 경도에 큰 영향을 주는 것으로 나타났으며, 유동성이 우수하며 부드러운 고체상의 파라핀 왁스를 사용한 경우에는 저광택의 소광성을 보여주었다. Photo-DSC의 ${\Delta}H$는 왁스를 함유한 코팅 시스템이 함유하지 않은 시스템 보다 높게 나타났는데, 특히 파라핀 왁스를 사용한 경우의 ${\Delta}H$가 PE 왁스를 사용한 경우에 비해 높게 나타났다. 이는 파라핀 왁스가 PE 왁스에 비해 더 효과적으로 공기 중의 산소를 차단하여 경화성이 높아진 것임을 의미한다. 또한 왁스의 산소 차단 효과는 경화속도와 밀접한 관계가 있는 것으로 확인되었다.

• 한국초전도ㆍ저온공학회논문지
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• 제11권1호
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• pp.1-4
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• 2009

Mechanical and electrical properties of silver stabilizer layer of coated conductor, which as prepared with nano silver paste as starting materials, have been investigated, Nano silver paste was coated on a YBCO film by dip coating process at a diping speed of 20m/min. Coated film was dried in air and heat treated at $400{\sim}700^{\circ}C$ in an oxygen atmosphere. Adhesion strength between YBCO and silver layer was measured by a tape est(ASTM D 3359). Hardness and electrical conductivity of the samples were measured by pencil hardness test (ASTM D 3363) and volume resistance test by LORESTA-GP (MITSHUBISHD, respectively. The sample heat-treated at $500^{\circ}C$ showed poor adhesion 1B, but samples heat treated at higher than $600^{\circ}C$ showed enhanced adhesion of 5B. The silver layer heat-treated at $700^{\circ}C$ showed the high hardness value larger than 9 H, low volume resistance, surface resistance value as well as superior current carrying capacity compared to sputtered silver. SEM observations showed that a dense silver layer was formed with a thickness of about $2{\mu}m$. Dip coated silver layer prepared by using nano silver paste showed superior electrical and mechanical characteristics.

• Korean Chemical Engineering Research
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• 제55권5호
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• pp.586-592
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• 2017

본 연구에서는 n-butyl acrylate (BA), methyl methacrylate (MMA), 2-hydroxypropyl methacrylate (HPMA) 및 acetoacetoxyethyl methacrylate(AAEM) 단량체를 부가 중합시켜 고형분이 75%인 아크릴수지를 합성하였다. 이때, 아크릴수지의 유리전이온도($T_g$)를 20, 30, $40^{\circ}C$로, 수산기가(OH value)를 60, 90, 120으로 변화시켰다. 그 결과, 아크릴수지의 점성도는 $T_g$와 수산기가가 증가할수록 증가하였다. 합성된 아크릴수지는 높은 가교밀도를 갖도록 설계되어 고탄력성과 고내구성을 유지하였다. 가교된 아크릴수지는 블록이소시아네이트(Desmodur BL-3175)와 경화 반응시켜 아크릴 우레탄 투명 도료를 제조하는데 사용되었다. 도료에 대하여 점성도, 접착성, 연필경도 및 $60^{\circ}$ 경면광택도 등의 측정을 통해 물리적 특성을 분석하였고, 아크릴 우레탄 투명 도료는 코일코팅용 상도 도료로서 적용되기 위하여 시편으로 제조되어 다양한 특성이 평가되었다. 제조된 도료는 접착력이 뛰어났고, $60^{\circ}$ 경면광택도와 연필경도에서 우수한 특성을 나타내었으며, 환경 친화적이었다.