• Journal of Adhesion and Interface
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• v.12 no.3
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• pp.99-104
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• 2011

Currently, automotive pre-primed coatings has been developed to overcome environmental regulations and to reduce manufacturing cost in automotive industry. By these reasons, an automotive pre-primed system has been investigated to remove the wash and pre-treatment process using a roll coating application. It is required to develop non-weldable pre-primed system for automotive structural adhesives, because pre-primed sheet coated with organic compounds is hard to be assembled by welding process. Primer 1 (polyester type) and primer 2 (urethane type) were designed to satisfy flexibility and formability for non-weldable pre-primed system. According to the results of physical property test of the primers, adhesion test such as single-lap shear test and T-peel test, primer 1 (polyester type) had better physical properties such as pencil hardness, solvent resistance, flexibility and adhesion with automotive adhesive than that of primer 2 (polyurethane type). In addition, the possibility of the non-weldable pre-primed system was applicable to automotive assembly process in place of welding process.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.166-171
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• 1997

IBED is a very promosing thin film deposition method because of its many advantages, such as excellent adhesion property of films to substrates, room temperature processing, ease of control over the composition and thickness of films, and so on, over the conventional techniques, It has been widely applied in the field of surface modification of materials in the last decade. In our laboratory, many kinds of thin films, such as wear-resistant hard coatings, corrosion and oxidation protective coatings, biomaterial films, buffer layer for high temperature superconductor films, and oxygen sensitive film, have been synthesized by IBED, and several industrial applications of the IBED films have been conducted.

• Ceramist
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• v.21 no.2
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• pp.83-88
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• 2018

There is close relation between the heat generation and the performance of electronic device. The durability and efficiency of the device are degraded due to heat generation. It is necessary to release the generated heat from an electronic device. Based on demands of the printed circuit board (PCB) manufacturing, the robust and reliable plating technique of PCB is necessary. In this study, we review various methods for improving the heat sink property. These methods were considered to enhance the adhesion between ceramic substrate as heat sink and metal layer as electrode.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.135-136
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• 2010

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.123-123
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• 2009

In our experiment, a PTFE was sputter-coated on substrates to induce water-repellent properties and the RF-magnetron sputtering method for fabrication of PTFE film is used due to the advantages of the simple process, time saving, environmentally friendly, insulating property, and a good adhesion property to substrates. As a result of the correlation between surface roughness of PTFE films and contact angle with water, we found that the roughness surfaces are proportioned to contact angles related to low interfacial energy.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1104-1110
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• 2003

There are many applications of nanostructures, have been suggested by lots of researchers. It is highly required to measure the properties of nano-sized materials for design and fabrication of the nanostructures. In this paper, several techniques for measuring the mechanical properties of nano-structures are presented laying emphasis on the activity of Nano Property Measurement Team in KIMM. Some advanced applications of nano-indenter are described for measuring elastic, visco-elastic, frictional and adhesive properties as well as the standard methods of it. Micro-tensile test technique with accurate in-plane strain measurement method is also presented and its role in the property measurement of nanostructures is discussed.

• Corrosion Science and Technology
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• v.11 no.1
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• pp.15-19
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• 2012

Both electrogalvanized and hot-dip galvanized steel sheets have been finally produced via organic-inorganic surface coating process on the zinc surface to enhance corrosion resistance and afford additional functional properties. Recently, POSCO has been developed a variety of chromate-free coated steels that are widely used in household, construction and automotive applications. New organic-inorganic hybrid coating solutions as chromate alternatives are comprised of surface modified silicate with silane coupling agent and inorganic corrosion inhibitors as an aqueous formulation. In this paper we have prepared new type of hybrid coatings and evaluated quality performances such as corrosion resistance, spot weldability, thermal tolerance, and paint adhesion property etc. The electrogalvanized steels with these coating solutions exhibit good anti-corrosion property compared to those of chromate coated steels. Detailed components composition of coating solutions and experimental results suggest that strong binding between organic-inorganic hybrid coating layer and zinc surface plays a key role in the advanced quality performances.

• Corrosion Science and Technology
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• v.6 no.2
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• pp.68-73
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• 2007

The toxicity of chromium that is used to impart corrosion resistance to galvanized steel created environmental and health-related concerns and generated a great deal of interest in developing chrome-free treatment coatings. In the present work, organic-inorganic composite coatings were used to coat electrogalvanized steel (EG) sheets for corrosion protection without degrading its weldability property. The new coatings composed of specially modified polyurethane dispersion hybridized with silicate and unique inorganic-organic inhibitors were developed during this work. It was found that about $1{\mu}m$ thickness of coating layer is secure enough in corrosion resistance of flat and formed part even after alkaline degreasing. Overall chemical resistances including fingerprint resistance and paint adhesion property were satisfied with the test specification of Sony technical standard of SS-00260-2002. Therefore, it is concluded that the newly developed chrome-free product can replace the conventional chromated product.

• Molecules and Cells
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• v.41 no.5
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• pp.373-380
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• 2018

Synapses and neural circuits form with exquisite specificity during brain development to allow the precise and appropriate flow of neural information. Although this property of synapses and neural circuits has been extensively investigated for more than a century, molecular mechanisms underlying this property are only recently being unveiled. Recent studies highlight several classes of cell-surface proteins as organizing hubs in building structural and functional architectures of specific synapses and neural circuits. In the present minireview, we discuss recent findings on various synapse organizers that confer the distinct properties of specific synapse types and neural circuit architectures in mammalian brains, with a particular focus on the hippocampus and cerebellum.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.6-9
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• 2010

Surface properties of polytetrafluoroethylene(PTFE) films fabricated by rf-magnetron sputtering system with UV surface treatment were investigated to increase water contact angle for their hydrophobic property. We found that the surface morphology and water contact angles of PTFE film modified as a function of the UV treatment times using UV-irradiation were influenced. The water contact angle of PTFE film with optimized UV treatment time for 15 minute showed a high hydrophobicity compared with the film without any surface treatment. We thought that it was due to the energy change of PTFE surface with an adhesion improvement to the glass surface as a smoothing a rough surface with needle-shape and/or the enhancement of an interface property as a removing some defects on the surface like a cleaning effect.