• Restorative Dentistry and Endodontics
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• 제24권3호
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• pp.473-481
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• 1999

This study evaluated the shear bond properties of IPS Empress glass ceramic to enamel and dentin surfaces with three ceramic surface treatments, and three resin cements. The influence of thermocycling was also investigated. The purpose of this study was to investigate the influences of resin cements, ceramic surface treatments, and thermocycling on shear bond properties. Ninety freshly extracted, noncarious human molars were selected for this study. The surface treatments of ceramic were etching <5.0% hydrofluoric acid, application of silane coupling agents(Tokuso Ceramic Primer, Clearfil porcelain bond, Monobond-S), and the combination of the two methods. Empress cylinders were bonded to enamel and dentin surfaces with three kinds of resin cements(Bistite resin cement, Panavia 21, Variolink). The specimens were aged in $37^{\circ}C$ distilled water for 24 hours. Half of the specimens were then thermocycled 500times between $5^{\circ}C$ and $55^{\circ}C$ with a dwell time of 15 seconds. Each specimen was debonded in shear mode and measured shear bond properties by using the universal testing machine(Zwick 020, Germany). The data were analyzed by SPSS/PC+(one-way ANOVA, Scheffe' s test and t-test). The results were as follows : 1. Without thermocyling, there was significant difference of shear bond strength to enamel surface between Bistite Resin Cement and Panavia 21 in case of etched and silane-treatment(p<0.05). 2. Without thermocyling, the shear bond strength of a group treated with silane and etching was significantly higher than that of a group treated with silane or etching with the application of Panavia 21 and Variolink(p<0.05). 3. A group treated with etching with the application of Variolink only showed a decrease of shear bond strength after thermocycling(p<0.05).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.86.1-86.1
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• 2015

As the feature size of Si-based semiconductor shrinks to nanometer scale, we are facing to the problems such as short channel effect and leakage current. One of the solutions to cope with those issues is to bring III-V compound semiconductors to the semiconductor structures, because III-V compound semiconductors have much higher carrier mobility than Si. However, introduction of III-V semiconductors to the current Si-based manufacturing process requires great challenge in the development of process integration, since they exhibit totally different physical and chemical properties from Si. For example, epitaxial growth, surface preparation and wet etching of III-V semiconductors have to be optimized for production. In addition, oxidation mechanisms of III-V semiconductors should be elucidated and re-growth of native oxide should be controlled. In this study, surface preparation methods of various III-V compound semiconductors such as GaAs, InAs, and GaSb are introduced in terms of i) how their surfaces are modified after different chemical treatments, ii) how they will be re-oxidized after chemical treatments, and iii) is there any effect of surface orientation on the surface preparation and re-growth of oxide. Surface termination and behaviors on those semiconductors were observed by MIR-FTIR, XPS, ellipsometer, and contact angle measurements. In addition, photoresist stripping process on III-V semiconductor is also studied, because there is a chance that a conventional photoresist stripping process can attack III-V semiconductor surfaces. Based on the Hansen theory various organic solvents such as 1-methyl-2-pyrrolydone, dimethyl sulfoxide, benzyl alcohol, and propylene carbonate, were selected to remove photoresists with and without ion implantation. Although SPM and DIO3 caused etching and/or surface roughening of III-V semiconductor surface, organic solvents could remove I-line photoresist without attack of III-V semiconductor surface. The behavior of photoresist removal depends on the solvent temperature and ion implantation dose.

• Elastomers and Composites
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• 제35권2호
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• pp.98-105
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• 2000

화학적 표면처리에 따른 카본블랙의 표면 관능기와 표면 자유에너지를 FT-IR과 접촉각 측정법을 이용하여 각각 관찰하였다. 산성과 염기성 용액으로 표면 처리한 카본블랙을 분석한 결과, 표면 관능기가 표면 자유에너지의 극성요소에 크게 영향을 미치는 것을 확인하였다. 반면에 무극성 용액으로 표면처리한 NCB와 염기성 용액으로 처리한 BCB의 경우 표면 자유에너지의 London 비극성 요소의 증가를 보이며 이에 따라 카본블랙/고무 복합재료의 경도, 파단신율, 그리고 인장강도와 같은 기계적 물성이 증가하는 것을 볼 수 있었다. 특히, 접촉각 측정을 통해 얻은 표면 자유에너지의 London 비극성 요소가 복합재료의 인장강도와 상관관계가 있음을 확인할 수 있었다. 이는 카본블랙의 London 비극성 요소가 카본블랙/고무 복합재료의 기본적인 기계적 물성에 크게 기여한다고 사료된다.

• 구강회복응용과학지
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• 제37권1호
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• pp.23-30
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• 2021

목적: 본연구의 목적은 다양한 산용액을 이용하여 지르코니아의 표면을 처리하여 표면의 양상과 골유착에 미치는 영향을 알아보는 것이다. 연구 재료 및 방법: 준비된 지르코니아 디스크에 다양한 산용액 및 광촉매 산부식을 이용하여 표면을 처리하였다. 각 시편을 SEM으로 관찰하고, 골유착을 관찰하기 위해 MC3T3E-1 세포를 이용하여 형광염색과 역전사 중합효소 연쇄반응을 통해 평가하였다. 결과: 처리한 방법에 따라 다양한 거칠기를 보였다. 불산처리군은 표면의 거칠기가 증가하였으나 약한 네트워크 구조를 가지고 있었다. 골유착능에서는 광촉매 산부식을 시행한 군에서 더 좋은 결과를 보였다(P < 0.05). 결론: 지르코니아를 광촉매 산부식방법으로 처리할 경우 다른 산처리방법에 비해 골유착능을 높이는데 효과적일 것으로 사료된다.

• 한국의류학회지
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• 제20권3호
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• pp.467-480
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• 1996

Interactions between PET POY and solvents were estimated by the changes in microstructure and surface morphology. Changes in microstructure and surface morphology by the solvent treatments were: an increase in crystallite size, a decrease in interplanar spacing, a change in degree of orientation of crystalline region, a change in surface characteristics.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1993년도 춘계학술발표회
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• pp.45-45
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• 1993

• The Journal of Advanced Prosthodontics
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• 제10권2호
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• pp.101-112
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• 2018

PURPOSE. The purpose of this study was to investigate the effect of various surface treatments (ST) on the shear bond strength of resin composite to three bilayer dental ceramics made by CAD/CAM and two veneering ceramics. MATERIALS AND METHODS. Three different bilayer dental ceramics and two different veneering ceramics were used (Group A: IPS e.max CAD+IPS e.max Ceram; Group B: IPS e.max ZirCAD+IPS e.max Ceram, Group C: Vita Suprinity+Vita VM11; Group D: IPS e.max Ceram; Group E: Vita VM11). All groups were divided into eight subgroups according to the ST. Then, all test specimens were repaired with a nano hybrid resin composite. Half of the test specimens were subjected to thermocycling procedure and the other half was stored in distilled water at $37^{\circ}C$. Shear bond strength tests for all test specimens were carried out with a universal testing machine. RESULTS. There were statistically significant differences among the tested surface treatments within the all tested fracture types (P<.005). HF etching showed higher bond strength values in Groups A, C, D, and E than the other tested ST. However, bonding durability of all the surface-treated groups were similar after thermocycling (P>.00125). CONCLUSION. This study revealed that HF etching for glass ceramics and sandblasting for zirconia ceramics were adequate for repair of all ceramic restorations. The effect of ceramic type exposed on the fracture area was not significant on the repair bond strength of resin composites to different ceramic types.

• 한국콘텐츠학회논문지
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• 제10권11호
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• pp.243-250
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• 2010

티타늄의 표면처리방법과 저온용융도재의 글레이징 온도 변화에 따른 티타늄-세라믹 보철물의 결합강도와 색조재현성에 관해 분석하고자 하였다. 표면처리방법에 따른 결합강도를 비교한 결과, TiN 코팅 처리한 STB1시편이 가장 높게 나타났으며, 전용결합재를 사용한 SB1시편, gold 코팅 처리한 SGB1시편 순으로 나타났다. 글레이징 온도에 따른 결합강도는 글레이징 온도가 $770^{\circ}C$인 시편들이 $720^{\circ}C$에서 글레이징을 실시한 시편들에 비하여 결합강도가 증가하였으며, $810^{\circ}C$에서 글레이징을 실시한 시편들에서는 결합강도가 감소하는 것으로 관찰되었다. 색조관찰 결과 글레이징 온도가 높아질수록 명도(${\Delta}L$)가 높아졌으며, 티타늄의 표면처리에 의한 색조가 티타늄-세라믹의 색조에 영향을 주었으며, 그 결과 SB1과 SGB3이 색조재현성이 가장 우수한 것으로 평가되었다.

• 대한치과기공학회지
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• 제35권2호
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• pp.121-126
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• 2013

Purpose: The aim of this research was to investigate difference in shear bond strengths of full-contour zirconia layered with porcelain. Methods: Disk-shaped (diameter: 12.0 mm; height: 3.0 mm) zirconia were randomly divided into six groups according to the surface conditioning method to be applied (N=90, n=15 per group): group 1-contol group(ZC); group 2-airborne particle abrasion with $50-{\mu}m\;Al_2O_3(5A)$; group $3-50-{\mu}m\;Al_2O_3$ + liner(5AL), group $4-110-{\mu}m\;Al_2O_3(1A)$; group $5-110-{\mu}m\;Al_2O_3$ + liner(1AL); group 6-liner(LC). On each block, zirconia porcelain was build up according to manufacturer's instructions. All samples were fixed with measuring jigs and shear bond strength were measured with Universal testing machine. Collected data were analyzed using SPSS(Statistical Package for Social Sciences) Win 12.0 statistics program. Results: LC showed the highest value($29.92{\pm}2.55$ MPa) and ZC showed the lowest value($13.22{\pm}1.37$ MPa). Zirconia liner and Alumina oxide groups was significantly higher shear bond strength than control(p<0.05). 5A (without liner $22.18{\pm}2.37$, with liner $22.84{\pm}1.74$ MPa) was higher shear bond strength than $110{\mu}m$ (without liner $20.18{\pm}2.38$, with $20.71{\pm}2.67$). Conclusion: Surface treatments may have advantage in bond strength improvement for full-contour zirconia layered with porcelain.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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• pp.1-5
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• 2003

This paper presented the effects of accumulation of surface charges on hydrophobicity level and the surface states of silicone polymer used for outdoor insulator treated by ultraviolet irradiation and corona discharge through measuring surface voltage decay of a corona-charged specimen were investigated. The surface resistivity by the method of the surface potential decay was compared with the value by the three electrodes methods. From this study, it was found that the accumulation of surface charges above a critical surface voltage on silicone insulating materials could lead to the temporary loss of surface hydrophobicity. In addtion, uv stress lead to a longer decay time of surface charges. We could conclude that the effects of surface charges on hydrophocity level and the changes of surface state by various artificial treatments were understood through a trend of surface potential decay.