• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.1-16
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• 1995

The purpose of this study was to investigate the effect of dentin bonding agents on the bond strength of composite resin restorations in case of applying the dentin bonding agents to acid etched enamel surfaces. Freshly extracted 364 bovine anterior teeth were selected as a adherents. 320 enamel specimens were divided into two groups(unetched group (1) and etched group (2) for testing the shear bond strength, 40 specimens were used for the hardness testing, and 4 specimens of rest were to observe the resin-tag formation into etched enamel surfaces. All surfaces of enamel specimens were polished with 320~1500 SiC paper under continuous running water. In Group (1), 100 enamel specimens were polished and unetched. 220 polished enamel specimens in Group (2) were etched with 37 % phosphoric acid solution for 60 seconds, washed with water for 20 seconds, and dried with a light air pressure for 60 seconds. Three kinds of dentin bonding agents(Gluma, Prisma, Scotchbond 2) were evaluated the effect on the bond strength to conditioned enamel surfaces. Shear bond strengths were measured on the three cases such as a coating of primer only, a coating of sealer only, and a sequential coating of primer and sealer to acid etched enamel surfaces were compared with the bond strengths measured by the coating of enamel bonding agent followed by the bonding of composite resin (Photo clearfil bright, Kuraray, Japan) to unetched and acid etched enamel surfaces. In addition, the hardness tested on the adhesive fractured surface between composite resin enamel as a mean of evaluation of a factor whether the mechanical bond strengths were affected and the penetration of dentin bonding agents into etched enamel surfaces was also observed. Bond strengths were measured using the method of shear bond strength by a universal testing machine (Instron-4467, USA), statistical test were applied to the results using a one way analysis variance(ANOVA), and hardness was measured by the Vicker's Hardness Tester(MHT-i, Matsuzawa, Japan) and the penetration of the resins were observed by the SEM (Hitachi, S-2300, Japan). The following conclusions were drawn; 1. Enamel bonding agent showed to affect the improvement of bond strength of composite resin to enamel surface both unetched and etched. 2. Dentin bonding agents could be resulted in increase of bond strength to unetched enamel surface, but there were no statistical significances. 3. Bond strengths to etched enamel surface were significantly decreased with a coating of dentin primer only. 4. Coating of sealer only and coating of primer and sealer noticed the similar bond strengths of composite resin to etched enamel using the enamel bonding agents. 5. The applying method proved to be more effective than the kinds of dentin bonding agents on the bond strength of composite resin to etched enamel than the kind of dentin. 6. Vicker's hardness numbers of dentin bonding agents were lower than that of composite resin, but the degree of penetration of dentin bonding agents into etched enamel surfaces was excellent.

• 폴리머
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• 제38권5호
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• pp.573-579
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• 2014

탄소나노튜브(CNT), 불소계 아크릴레이트 2,2,2-trifluoroethylmethacrylate(3FMA) 및 유-무기 조성비와 같은 합성조건을 달리하여 제조된 자외선 경화형 유-무기 하이브리드 코팅 막의 표면특성 및 내오존성에 대해 연구하였다. 코팅 막은 금속 알콕사이드 전구체인 tetraethoxysilane(TEOS)와 실란 커플링제인 methacryloyloxypropyltrimethoxysilane (MPTMS)로 구성된 유-무기 혼성 용액에 탄소나노튜브 및 3FMA와 자외선 경화를 위한 유기물을 첨가하여 제조된 코팅제를 자외선 경화시켜 제조하였다. 제조된 코팅 막의 내오존성 및 기재와의 접착력은 TEOS, 3FMA 및 CNT의 함량에 크게 영향을 받는다는 것을 확인하였다. 특히, 탄소나노튜브가 첨가된 코팅 막은 우수한 내오존성 및 접착력 뿐만 아니라 높은 표면경도를 나타내었다. TEOS의 경우, 함량이 증가할수록 표면경도 및 내오존성은 향상되었지만, 기재와의 접착력은 감소되었다. 불소아크릴레이트 3FMA의 경우, 함량이 증가할수록 내오존성은 향상되었지만 표면경도는 감소하였다.

• 한국식품저장유통학회지
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• 제8권2호
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• pp.181-186
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• 2001

The objective of this study is to determine the effect of soy protein isolate (SPI) film coating on the color, firmness, viscosity and weight loss of Rice Cake stored at 15, 20 and $25^{\circ}C$ (RH 50%) for 30 days. Raw materials mixed with SPI and cocoa powder (10:0, 7:3, 5:5, 3:7, w/w) were prepared. After adding sugar and shortening to raw materials, the mixture were refined to 25 micron of particle size. Coating of Rice Cake were carried out at $65^{\circ}C$. SPI coated Rice Cake had higher internal and external firmness comparing to the control at $25^{\circ}C$. SPI coated Rice Cake showed smooth surface morphology and had 0.71-1.01 mm of thickness. SPI coated Rice Cake showed less weight loss for 30 days compared to controls. SPI coating solution was successfully coated on Rice Cake and extended shelf-life over 15 days at room temperature.

• 대한치과기공학회지
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• 제29권2호
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• pp.213-223
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• 2007

The success of a porcelain fused to metal (PFM) restoration depends upon the quality of the porcelain-metal bond. The adhesion between metal substructure and dental porcelain is related to the diffusion of oxygen to the reaction layer formed on cast-metal surface during firing. The purposed of this investigation was to study the effects of gold based bonding agent on Ni-Cr alloy-ceramic adhesion between porcelain matrix, gold based bonding agent and metal substructure interface. gold based bonding agent have been applied as an intermediate layer between a metal substructure and a ceramic coating. gold based bonding agent(Aurofilm NP, Metalor, Swiss) was applied on Ni-Cr alloy surface by four method. Surfaces only air abraded with 110${\beta}\neq$ Al2O3 particles were used as control. metal ceramic adhesion was evaluated by a biaxial flexure test(N=5) and volume fraction of adherent porcelain was determined by SEM/EDS analysis. Result of this study suggest that the layering sequence of gold based bonding agent is very important and can improve porcelain adherence to PFM.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.316-320
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• 2009

폴리카보네이트(polycarbonate)는 가볍고, 내충격성 및 가공성이 우수하여 광학기기의 렌즈 및 각종 건축물의 투명 소재 등에 유리의 대체품으로서 널리 이용되고 있으나 낮은 표면경도를 가지고 있어 유통 또는 사용시의 접촉으로 인하여 제품에 손상을 줄 염려가 있다. 따라서 본 연구에서는 폴리카보네이트 필름에 아크릴레이트 올리고머, 모노머, 용매, 염료, 실리콘 아크릴레이트, 그리고 광개시제 등을 다양한 함량비율에 따라 혼합한 코팅용액을 제조하고, 구성 성분의 비율에 따른 폴리카보네이트 필름의 표면 경도, 접착력, 그리고 투과율의 변화를 실험하였다. 그 결과 최대 연필 경도가 2H이고, 접착력과 가시광선 투과율이 우수한 코팅용액의 조성을 얻었다. 색상코팅 실험 결과, 기존 산화물 증착에 의해 구현하던 색상을 본 실험에서 제조한 코팅 용액을 사용하여 거의 대부분 구현할 수 있었으며, 이를 바탕으로 색상 윈도우 렌즈를 제작한 결과, 매우 깨끗하고 균일한 색상과 표면을 가졌다.

• 한국표면공학회지
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• 제41권6호
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• pp.312-324
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• 2008

In this study, the functional property as a super abrasive material was secured for CBN powder by the electroless Ni-P plating on the surface of the particle. The plating solution has been prepared to control the surface morphology by regulating surfactants and process conditions. The effects of processing parameters on the surface morphology of CBN powder was discussed. The results are summarized as follows; A stable plating tendency was achieved from 1 hour after quantitatively dropping reducing agent. It was observed that more than 50% of the weight gain was obtained by Ni-P coating on the surface of CBN super abrasive powder. The morphology of the Ni-P coating layer is consisted of botryoidal and spiky type and it could be controlled by regulating processing parameters. Superior characteristic in terms of surface morphology was found in the nonionic surfactant XL-80N. It was found that XL-80N considerably decreased surface tension of CBN powder and Ni-P alloy surface then enhance wettability as well as plating rate. Metal coated CBN powder as a raw material of resin bond wheel has been developed through this investigation.

• 한국산학기술학회논문지
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• 제11권9호
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• pp.3615-3620
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• 2010

본 연구는 건축자재로 널리 사용되는 PVC바닥상재 표면에 내오염성과 항균성을 증가시키기 위한 광경화형 코팅액 개발에 관한 것이다. PVC 바닥상재용으로 사용되는 우레탄-아크릴 수지에 수용성대전방지제와 항균제를 배합하여 오염 및 정전기로부터 상재를 보호하고 미생물에 의한 전염성질환을 예방할 수 있는 광경화형 내오염/항균 코팅액에 관한 실험을 수행하였다. 연구결과, 수지에 수용성대전방지제 15%와 항균제 1%를 혼합하여 제조한 코팅액을 bar-coater No.12로 코팅한 표면이 전기저항($10^9{\Omega}/cm^2$), 내오염도(매직 Test, 먼지부착 Test) 및 부착력(100%) 양호, 항균성(99.99%)로 가장 좋은 물성을 보였다.

• 한국안전학회지
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• 제27권3호
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• pp.96-103
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• 2012

The purpose of this study is evaluate the ability of coating materials developed in order to prevent the durability deterioration of the concrete structure. Neutralization test, freezing and thawing test, and sulfate resistance test were performed in this study. Test results show that the developed coating material is effective against durability deterioration.

• 보존과학회지
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• 제33권3호
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• pp.203-214
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• 2017

본 연구에서는 야외 플라스틱 작품에 많이 사용되고 있는 유리섬유강화플라스틱(FRP)을 대상으로 자외선에 의한 색도 및 광택도, 접촉각 변화, 적외선 분광분석을 통해 열화 특성을 확인하였으며, FRP의 열화를 예방하고자 자외선 차단 코팅제를 제조하여 코팅제의 성능 평가를 진행하였다. 자외선 열화 결과, FRP의 표면변화는 기공 이외에 다른 변화는 관찰되지 않았다. 색차는 열화 초기에 급격히 증가하였는데 이는 적외선 분광분석 결과와도 유사하였다. 광택도 및 접촉각의 경우 뚜렷한 변화는 확인되지 않았다. 코팅제 처리에 따른 특정한 표면 변화는 관찰되지 않았으나 색차 비교 결과, 미처리 시편보다 색 변화가 낮게 측정되어 변색 제어가 가능함을 확인하였다. 코팅제 도포 후 열화에 따른 광택도 및 접촉각 변화가 일부 관찰되었으나 자외선 차단 코팅제는 상대적으로 안정한 것으로 나타났다. 적외선 분광분석 결과, 화학적 변화가 미미함에 따라 코팅제가 일정 기간 동안 열화를 지연시키는 것으로 보인다. 본 연구를 통해 작품 재료로써 FRP의 자외선 열화 양상을 파악하였으며, 제조한 자외선 차단 코팅제의 성능 평가를 통해 야외 FRP 작품의 보존 방안으로써 적용 가능성을 확인하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.81-82
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• 2022

Al and Zn are used to protect the steel structures from corrosion. In the present studies, 15Al-85Zn alloy wires has been used for the deposition of coating by arc thermal spray process. Moreover, this process of coating exhibited severe defects formation, therefore, this coating was post-treated with different concentrations i.e. 0.05, 0.1 and 0.5M sodium hexa meta phosphate (Na6[(PO3)6]: SHMP) to fill to defects of deposited coatings and assessed their corrosion resistance in 3.5 wt.% NaCl solution with exposure periods. After the treatment, the porosity of the coating reduced significantly by formation of composite oxide films onto the coating surface. Initially, 0.5 M SHMP treated coating exhibited highest in total impedance due to significant reduction of porosity but once the exposure periods are extended, the composite oxides are dissolved, thus, total impedance is decreased.