• 한국표면공학회지
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• 제49권6호
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• pp.549-554
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• 2016

Low melting metals are difficult to weld because it is vaporized. But epoxy resin make bonding possible using low melting material and dismissal materials. This study is to improve the bonding strength of epoxy and substrate by mechanical and electrochemical methods. In case of mechanical work, bonding strength is 17.6MPa and in case of pre-work, bonding strength is 15.3MPa. When anodizing and mechanical work is applied, bonding strength is 25.3Mpa is increased 165%. When anodizing is applied, bonding strength is 27.6Mpa.

• 대한치과교정학회지
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• 제35권6호
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• pp.433-442
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• 2005

본 연구의 목적은 브라켓 접착 시 산부식과 전처리 과정을 결합하여 접착 단계를 단순화시킨 self-etching primer (SEP)를 차용하는 경우 접착제 종류와 타액의 존재 유무에 따른 전단결합강도의 차이에 관하여 비교 연구 하는 것이다. 소의 하악 영구 전치를 포매하여 만든 시편을 접착제의 종류에 따라 레진 접착제와 레진 강화형 글래스 아이오노머 접착제를 이용한 군으로 나누었고 각각 37% 인산으로 산부식 후 기존의 본딩용 프라이머를 사용하여 접착한 군과, SEP를 사용하여 접착한 군으로 분류하고, 타액 오염 유무에 따라 다시 각 군을 분류하여 전단결합 강도를 측정하였다. 그 결과 레진 접착제로 브라켓을 부착한 경우 SEP를 사용하여 접착한 군의 전단결합강도는 인산 처리군에 비해 낮은데 비해 레진 강화형 글래스 아이오노머를 사용한 경우, 전처리법에 따른 전단결합강도는 통계적으로 유의한 차가 없었으며, 접착제의 종류에 관계없이 타액 오염이 존재 시에는 SEP를 사용한 군이 인산처리군에 비해 높은 전단결합강도를 보였다. 이상의 결과에서 SEP를 사용 시 레진 접착제와 레진 강화형 글래스 아이오노머 접착제 모두 임상적으로 사용 가능한 전단결합강도를 보였으며, 특히 타액에 오염된 치면에서도 SEP를 사용하여 브라켓을 접착하는 것은 적절한 결합강도를 얻을 수 있으므로 임상적으로 유용할 것으로 생각된다.

• 접착 및 계면
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• 제7권4호
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• pp.1-9
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• 2006

The single lap joint is the most studied joint in the literature in terms of both theory and practice. It is easy to manufacture and the lap shear strength is a useful value for strength assessment and quality control. Simple design rules exist such as the one present in standard ASTM 1002 or in a recent paper by Adams and Davies. The main factors that have an influence on the lap shear strength are the type of adhesive, i.e. ductile or brittle, the adherend yield strength and the overlap length. The overlap increases the shear strength almost linearly if the adhesive is sufficiently ductile and the adherend does not yield. For substrates that yield, a plateau is reached for a certain value of overlap corresponding to the yielding of the adherend. For intermediate or brittle adhesives, the analysis is more complex and needs further investigation. In order to quantify the influence of the adhesive, the adherend and the overlap on the lap shear strength, the experimental design technique of Taguchi was used. An experimental matrix of 27 tests was designed and each test was repeated three times. The influence of each variable could be assessed as well as the interactions between them using the statistical software Statview. The results show that the most important variable on the lap shear strength is the overlap length followed by the type of adherend.

• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.381-391
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• 1999

A new 5th generation adhesive system(ONE-STEP) has been supplied which operators can apply to conditioned tooth surfaces by one simplified step. The purpose of this study was to determine whether different methods of adhesive application and various air drying duration after applying adhesive affect the shear bond strength of composite resin to dentin, and to evaluate the adhesive pattern of composite resin and dentin under SEM. Seventy-seven extracted human molar teeth were cleaned and mounted in palstic test tubes. The occlusal dentin surfaces were exposed with Diamond Wheel Saw and smoothed with Lapping and Polishing Machine (South Bay Technology Co., U.S.A.). Teeth were randomly divided into 7 groups (n=11), In experimental A group, adhesive was applied to dentin with agitation for 20 sec. In experimental N-A group, adhesive were continuously applied to dentin for 20 sec. Also control and experimental 1, 2, 3, 4 groups were dried for 10, 0, 5, 20, 30 seconds after applying adhesive, respectively, Adhesives were light cured for 10 sec. A gelatin capsule 5mm in diameter was filled with Aelitefil$^{TM}$ composite resin, placed on the treated dentin surface and light cured for 40 see, from three sides, All specimens were stored in distilled water at room temperature for 24 hours. The shear bond strengths were measured using a universal testing machine(AGS-1000 4D, Japan) at a crosshead speed of 5mm/min. An one-way ANOVA and LSD test were used for statistical analysis of the data. For SEM evaluation, seven specimens were made and sectioned. Representive postfracture and seven specimens were mounted on brass stubs, sputter-coated with gold and observed under SEM. The results were as follows : 1. The shear bond strength of experimental A group which adhesive were applied to dentin with agitation was higher than that of experimental N-A group (continuous application), and there was significant difference between two groups (p<0.01). 2. The interface between composite and dentin according to different application methods showed close adaptation in experimental A group and showed tinny gap in experimental N-A group. 3. The shear bond strength accoding to various air drying duration was the lowest value(7.57${\pm}$2.60 MPa) in experimental 1 group, so there was significant difference between experimental 1 group and other four groups (p<0.05). But there was no significant difference of shear bond strength between four groups (p>0.05). 4. The interface between composite and dentin according to various air drying duration showed close adaptation in control group and tinny gap in experimental 3 and 4 groups. But experimental 1 and 2 groups showed $30{\mu}$ and 6 - $10{\mu}m$ thick gaps, respectively.

• Journal of Korean Dental Science
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• 제2권2호
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• pp.5-11
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• 2009

Objectives : This study investigated the hypothesis that the dentin bond strength of self-etching adhesives (SEAs) may be improved by applying a coat of hydrophobic, neutral adhesive resin in addition to SEA. Method and Materials : The bond strengths of two SEAs - Experimental SEA (EX) and Adper Prompt (AP) - were measured with three bonding protocols. The D/E resin of All-Bond 2 was applied as the hydrophobic, neutral adhesive. Clearfil SE Bond (SE, self-etching primer system) and All-Bond 2 (AB, total etching system) were used as references. The following protocols were used: (1) EX1 (EX 1 coat); (2) EX2 (EX 2 coats); (3) EX+ (EX 1 coat + D/E resin); (4) AP1 (AP 1 coat); (5) AP2 (AP 2 coats); (6) AP+ (AP 1 coat + D/E resin); (7) SE (SE primer + SE bond); (8) SE+ (SE primer + D/E resin); (9) AB (etching + AB primer + D/E resin). Filtek Z250 composite resin was built up and the microtensile bond strength (MTBS) values of the specimens were compared. The fractured surfaces were observed using SEM. Results : When SEA was used as self-etching primer and hydrophobic, neutral adhesive was applied as well, MTBS was significantly higher than that when either one coat or two coats of SEA only were used (p < 0.05). Conclusion : The hydrophobic, neutral adhesive improved the integrity of the bonded interface obtained with SEA.

• 보존과학회지
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• 제27권3호
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• pp.261-268
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• 2011

본 연구는 문헌연구를 바탕으로 하여 전통적인 방법으로 풀을 조제하여 배접하는 경우 첨가제가 풀의 성질 및 접착특성에 미치는 영향을 고찰한 결과이다. 본 연구는 향후 회화문화재의 보존처리용 천연접착제 개발을 위한 기초자료로 제시하고자 한다. 따라서 본 연구에서는 접착제에 첨가제가 미치는 영향을 검토하기 위하여 임원경제지(林園經濟志), 거가필용사류전집(居家必用事類全集), 다능비사(多能鄙事), 죽여산방잡부(竹嶼山房雜部)에서 공통적으로 사용되고 있는 백반과 황랍을, 장황지(裝潢志)와 제민요술(濟民要術)에서 공통적으로 사용되고 있는 석회를 첨가제로 사용하여 그 특성 즉, 점도, pH, 유연성, 박리강도, 항균성, 방미성, 보존성 등을 측정하여 고찰하였다. 그 결과 첨가제 고유의 특성이 풀의 특성에 큰 영향을 미치는 것을 알 수 있었다. 백반은 유연성을 증가시켰으나, 점도, 접착강도, pH는 감소시켰으며, 황랍은 유연성, 점도, 접착강도, pH를 모두 감소시켰으며, 석회는 유연성, 점도, pH, 접착강도를 모두 증가시키는 경향을 나타내었다.

• 대한소아치과학회지
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• 제33권3호
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• pp.377-387
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• 2006

본 연구는 자가산부식 접착시스템과 자가산부식 프라이머 접착시스템의 다층적용이 혼성층 및 adhesive layer의 형성 양상, 그리고 전단결합강도에 미치는 영향 등을 비교 평가하기 위하여 시행되었다. 영구 구치 140개의 치아를 근원심으로 분할하여 협면 혹은 설면의 상아질을 이용하였다. 각 접착시스템을 1회, 2회, 3회 도포, 그리고 1회 도포 후 광중합한 후 1회의 추가 도포한 군으로 분류하였다. 전단결합강도와 혼성층 및 adhesive layer 두께를 측정하여 분석한 결과 다음과 같은 결론을 얻었다. 1. 모든 접착제에서 도포횟수가 증가함에 따라 adhesive layer의 두께가 증가하였으며 (p<0.05), Adpor Prompt L-Pop과 Xeno III에서는 자가산부식 프라이머 시스템에서보다 작게 나타났다(p<0.05). 2. Adpor Prompt L-Pop에서 혼성층은 도포횟수에 따라 혼성층의 두께도 증가하였다(p<0.05). 3. Unifill Bond와 Clearfill SE Bond의 전단결합강도는 Scotchbond Multi-Purpose Plus와 Adpor Prompt L-Pop에서보다 높게 나타났으며 (p<0.05), Xeno III와는 유사하였다. 4. Adpor Prompt L-Pop은 접착제의 도포횟수가 증가함에 따라 전단결합강도는 유의하게 증가되었으며(p<0.05), AdheSE에서는 3회 도포한 경우 전단결합강도가 감소하는 경향을 보였다(p>0.05). 5. Adpor Prompt L-Pop과 Xeno III에서 첫 층을 중합한 후 두 번째 층을 추가 도포한 경우 전단결합강도는 감소하였다(p<0.05).

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.370-376
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• 2001

When an adhesive joint is exposed to high environmental temperature, the tensile load capability of the adhesive joint decreases because the elastic modulus and failure strength of structural adhesive decrease. The thermo-mechanical properties of structural adhesive can be improved by addition of fillers to the adhesive. In this paper, the elastic modulus and failure strength of adhesives as well as the tensile load capability of tubular single lap adhesive joints were experimentally and theoretically investigated with respect to the volume fraction of filler (alumina) and the environmental temperature. Also the tensile modulus of the fille containing epoxy adhesive was predicted using a new equation which considers filler shape, filler content and environmental temperature. The tensile load capability of the adhesive joint was predicted by using the effective strain obtained from the finite element analysis and a new failure model, from which the relation between the bonding length and the crack length was developed with respect to the volume fraction of filler.

• Journal of Microbiology and Biotechnology
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• 제21권11호
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• pp.1199-1202
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• 2011

Infection of surgical wounds is a severe problem. Conventional tissue reattachment methods have limits of incomplete sealing and high susceptibility to infection. Medical adhesives have several advantages over traditional tissue reattachment techniques, but still have drawbacks, such as the probability of infection, low adhesive strength, and high cytotoxicity. Recently, a new medical adhesive (new-adhesive) with high adhesive strength and low cytotoxicity, composed of aldehyded dextran and ${\varepsilon}$-poly(L-lysine), was developed. The antimicrobial activity of the new-adhesive was assayed using agar media and porcine skin. In the agar diffusion method, inoculated microorganisms that contacted the new-adhesive were inactivated, but this was not dependent on the amount of new-adhesive. Similar to the agar media results, the topical antimicrobial effect of new-adhesive was confirmed using a porcine skin antimicrobial assay, and the effect was not due to physical blocking based on comparison with the group whose wounds were wrapped.

• 폴리머
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• 제36권2호
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• pp.119-123
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• 2012

금속 박막 접착제로 사용되는 용제형 폴리우레탄 접착제의 라미네이팅 조건에 따른 접착 메커니즘과 이에 따른 접착력 변화를 살펴보았다. 강판에 도포된 접착제의 열처리 온도와 시간에 따라 폴리우레탄 접착제의 blocking agent로 사용된 옥심이 분해되어 이소시아네이트기가 발현되고 이들이 강판과 알루미늄 포일의 하이드록실기와 반응하여 강판 접착이 이루어짐을 알 수 있었다. 접착 강도는 접착 온도 및 시간에 따라 발생된 이소시아네이트 함량과 밀접한 관계가 있음을 확인하였다. 하지만 지나친 접착 온도 및 접착 시간의 증가는 접착제에 함유된 용매의 감소와 접착제 분해를 유발시켜 접착 강도를 감소시킴을 알 수 있었다.