• 폴리머
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• 제34권1호
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• pp.52-57
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• 2010

고 신뢰도와 높은 물성을 갖는 이방성 전도성접착제(anisotropic conductive adhesive, ACA)용 레진 개발을 위하여, 환원특성을 갖는 카르복실산을 포함한 bisphenol F계열의 에폭시 레진에 저융점 솔더입자(low melting point alloys, LMPA)를 분산시켜 제조하였다. LMPA의 융점에서의 에폭시 레진의 경화특성 및 온도에 따른 유변학 특성을 동적 시차 주사 열량계(differential scanning calorimeter, DSC)와 레오미터(rheometer)로 측정하여 최적화된 ACA 접합 공정을 설계하였다. 접합 공정시 LMPA 표면에 생성되는 산화막을 제거하여 높은 전기전도도와 안정적인 전기적 특성을 얻을 수 있도록 세가지 종류의 카르복실산을 환원제로 사용하여 각각의 젖음(wetting) 특성을 확인하였다. 부틸 카르복실산은 $28^{\circ}$의 낮은 젖음각을 나타내었으나, 경화반응 중 다량의 기포가 발생하는 문제가 있었다. 그러나, 이관능성 카르복실산(1,3-bis(2-carboxypropyl)tetramethyl disaoxane(2-CTMS)) 및 1,3-bis(3-carboxypropyl)tetramethyl disiloxane(3-CTMS))의 경우, 기포의 발생 없이 각각 $18^{\circ}$와 $20.3^{\circ}$의 매우 우수한 젖음 특성을 보였다.

• 접착 및 계면
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• 제3권1호
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• pp.20-23
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• 2002

The wetting properties of an uncured epoxy resin on both clean and oiled, galvanised steel have been studied. Since the polymer is very viscous at ambient temperature, and also with an aim to simulate industrial conditions, the spreading of drops of resin during a heating cycle (temperature increase at $10^{\circ}C/min$) was recorded and analysed. On clean steel, a contact angle, ${\theta}$, vs time, t, plot shows sigmoidal behaviour, whereas on the oiled substrate, spreading almost ceases in an intermediate stage. This strange behaviour is attributed to significant oil absorption by the polymer.

• 유변학
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• 제11권1호
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• pp.34-43
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• 1999

수지 이동 성형공정에서 섬유직조가 수지에 의해 함침될 때 발생하는 기공 또는 나쁜 젖음성은 최종 성형품의 물성 저하에 심각한 영향을 미치게 된다. 본 연구에서는 수지이동 성형공정에서의 이러한 문제점을 극복하기 위한 기초 데이터를 제공하기 위하여, 실란 커플링제를 사용한 섬유의 표면 개질이 수지의 유동특성과 수지와 섬유 사이의 젖음성 및 기공함량에 미치는 영향을 조사하였다. 빔 형태의 금형을 대상으로 에폭시 수지와 평직형태의 유리섬유를 사용하여 미시적인 유동가시화 실험 및 경화실험을 수행하였다. 섬유의 표면을 개질함으로써 수지와 섬유 사이의 동적 접촉각이 감소하고 위킹속도는 증가한 것으로 나타났으며, 이러한 결과로부터 본 연구에서 사용한 화학적 표면개질이 섬유직조의 젖음성 및 미시적 흐름 거동을 향상시킬 수 있는 중요한 요인임을 확인할 수 있었다. 또한 수지의 높은 온도와 낮은 침투 속도는 동적 접촉각을 감소시키기 위한 중요한 가공 변수임을 알 수 있었다. 그러나 섬유직조의 투과성은 표면을 개질하였을 경우 오히려 감소하였는데, 이는 젖음성의 향상으로 인하여 수지와 섬유 사이의 접촉시간의 증가에 기인하는 것으로 생각된다. 마지막으로 경화공정을 통해 제조된 시편의 기공 함량을 측정 비교한 결과, 표면개질은 수지이동 성형공정에서의 기공형성에도 중요한 변수로 작용하여, 수지와 섬유 사이의 젖음성을 향상시키고, 최종 성형품의 기공함량을 감소시킴을 확인할 수 있었다.

• 마이크로전자및패키징학회지
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• 제22권1호
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• pp.35-41
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• 2015

In this study, in order to improve the reliability of ACF interconnections, solder ACF joints were investigated interms of solder joint morphology and solder wetting areas, and evaluated the electrical properties of Flex-on-Board (FOB) interconncections. Solder ACF joints with the ultrasonic bonding method showed excellent solder wetting by broken solder oxide layers on solder surfaces compared with solder joints with remaining solder oxide layer bonded by the conventional thermo-compression (TC) bonding method. When higher target temperature was used, Sn58Bi solder joints showed concave shape due to lower degree of cure of resin at solder MP by higher heating rate. ACFs with epoxy resins and SAC305 solders showed lower degree of resin cure at solder MP due to the slow curing rate resulting in concave shaped solder joints. In terms of solder wetting area, solder ACFs with $25-32{\mu}m$ diameters and 30-40 wt% showed highest wetted solder areas. Solder ACF joints with the concave shape and the highest wetting area showed lower contact resistances and higher reliability in PCT results than conventional ACF joints. These results indicate that solder morphologies and wetting areas of solder ACF joints can be controlled by adjustment of bonding conditions and material properties of solder and polymer resin to improve reliability of ACF joints.

• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.97-112
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• 1995

The purpose of this study was to evaluate the effect of wetting condition made by drying time on bonding of resin cement to dentin. Freshly extracted bovine teeth were grinded to expose flat dentin surfaces. After the exposed dentin surfaces were treated with pretreatment agents and water rinse, each wetting condition of dentin surfaces was made according to drying times and methods including slight blow bry for I-second by air syringe, blow dry for 20-second by air syringe, and 12-hour dry in desiccator respectively. and then, previously made composite resin specimens were bonded onto each conditioned dentin surface of the specimen using Panavia-21(Kuraray Co.), Bistite(Tokuso Co.), and Choice(use with All bond-2, Bisco Inc.) resin cement according as manufacturer's instruction. Bonded specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured, cohesive failure rate was calculated, and fractured dentin surfaces and acrylic rod sides were examined under scanning electron microscope. The result were as follows ; In the group of bonding with Panavia-21 resin cement, higher tensile bond strength was seen in 12-hour dry group than in I-second and 20-second dry group(p<0.01). In the group of bonding with Bistite resin cement, higher tensile bond strength was seen in 1-second dry group than in 20-second and 12-hour dry group(p<0.01). In the group of bonding with Choice resin cement, no significant differences of bond strength under given drying time were seen. Cohesive failure rates derived from the groups of bonding with Panavia-21 and Choice resin cement were increased with the increase of tensile bond strength in each drying time. On SEM examination of fractured surface, adhesive failure mode with fractured resin tags was mostly seen in wet condition with I-second drying time in the group of bonding with Panavia-21 resin cement, mixed failure mode with shortened and fractured resin tag was seen in the group of bonding with Bistite resin cement, and regardless of drying time, and cohesive-adhesive mixed failure mode with fracture of 'Hollow' typed resin tags was mainly seen in the group of bonding with Choice resin cement.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.249-252
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• 2000

To overcome problems of excavation technology far repairing or replacing underground buried pipes which are worn out or damaged, various trenchless repair-reinforcement technologies have been invented. But these trenchless technologies also have many problems in the aspect of economy and convenience of operation. In this research, the repair-reinforcement process using RTM (Resin Transfer Molding) which can solve problems of present trenchless technologies was developed. The resin wetting and void removal during RTM process to form large composite structures inside of buried pipes were experimentally investigated. From the experiment, it was found that the new technology had advantage over conventional methods by employing appropriate process parameters and void removal vents.

• Macromolecular Research
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• 제10권4호
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• pp.194-203
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• 2002

In resin infusion process(RIP), the fiber and the resin are in contact with each other for an impregnation step and often results in flow-induced defects such as poor fiber wetting and void formation. Resin flow characteristics in transverse direction and process modeling for woven fabric were studied, and the process modeling was applied to the manufacturing of hybrid composite materials. This study also considered the compressibility of woven fabrics in a series of compression force, and it was fitted well to an elastic model equation. Void formation was varied with the processing conditions in the stage of manufacturing composites using RIP. It was concluded from this study that proper combination of pressure build-up and dynamic heating condition makes important factor for flow-induced composite processing.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년 추계학술발표대회 개요집
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• pp.175-177
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• 2006

Electrically Conductive Adhesives(ECAs) with solderable particles have been developed as an alternative to Pb-free solders. Our previous study proved that good wettability of solder particle is a prerequisite for the establishment of conduction paths. In this paper, two types of ECAs were formulated and the wetting characteristic low-melting-point Sn-In solder on Cu and Ni/Au pads was investigated. It was found that Sn-In solder in the developed resin material with reduction capability shows good wettability, especially on Cu pad.

• Composites Research
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• 제30권3호
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• pp.169-174
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• 2017

유리섬유(GF) 강화 복합재료는 금속에 비해 경량화의 장점으로 인해 기체 부품 산업의 높은 성장률과 방산 산업의 발전으로 수요는 증가되고 있으며 제품의 형태를 다양하게 제작할 수 있는 RTM 공정으로 산업적으로 이용되고 있다. 본 연구에서는 경화제의 분자량에 의한 가교 밀도 차이에 따라 변화되는 RTM의 성형성과 복합재료의 기계적 물성 및 계면 물성의 차이를 관찰하고자 하였다. 이를 위해 동일한 에폭시를 사용하였으며 유사한 화학 구조의 경화제를 이용하였다. 시편은 RTM 공법으로 제작하였으며 기지의 특성을 알아보기 위해 점도 측정 및 기지 주입시간을 측정하였다. 유리 섬유/에폭시 복합재료의 기계적 물성을 실험하여 굴곡 강도를 측정하였으며 계면 물성을 평가하기 위해 층간전단강도(ILSS)와 계면전단강도(IFSS)를 측정하였다. RTM 공정 시 기지의 점도에 의해 섬유의 함침정도에 따라 복합재료의 섬유 무게 분율(wt %)은 변화되고 이에 따라 유리섬유/에폭시 복합재료의 기계적 물성의 차이가 확인되었다.

• ETRI Journal
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• 제32권2호
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• pp.342-344
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• 2010

A novel, maskless, low-volume bumping material, called solder bump maker, which is composed of a resin and low-melting-point solder powder, has been developed. The resin features no distinct chemical reactions preventing the rheological coalescence of the solder, a deoxidation of the oxide layer on the solder powder for wetting on the pad at the solder melting point, and no major weight loss caused by out-gassing. With these characteristics, the solder was successfully wetted onto a metal pad and formed a uniform solder bump array with pitches of 120 ${\mu}m$ and 150 ${\mu}m$.