• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.188-192
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• 2007

In this work, the effects of chemical treatment of polyimide films were studied by FT-IR, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angles. The adhesion characteristics of the films were also investigated in the peel strengths of polyimide/aluminum films. The increases of surface functional groups of KOH-treated polyimide films were greatly correlated with the polar component of surface free energy. The peel strength of polyimides to metal substrate was also greatly enhanced by increasing the KOH treatment time, which can be attributed to the formation of polar functional groups on the polyimide surfaces, resulting in enhancement of the work of adhesion between polymer film and metal plate.

• Journal of the Korean institute of surface engineering
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• v.39 no.4
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• pp.166-172
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• 2006

Metallized Polyimide films are extensively used as base materials in microelectronics, optical and automotive applications. However it is difficult to deposit metals on those because of their structural stabilities. In this work, polyimide films are modified by a wet process with alkalinemetalhydroxide and additives to introduce functional groups. The surface molecular structures of polyimide are investigated using X-ray photoelectron spectroscopy(XPS), fourier transform infrared reflection spectroscopy(FTIR-ATR), atomic force micro-scopic(AFM). XPS spectra and FTIR spectra show that the surface structure of polyimide is converted into potassium polyamate. AFM image and AFM cross-sectional analyses reveal the increased roughness on the modified surface of polyimide films. As a result, it is shown that the adhesion strength between polyimide surface and electroless nickel layer is increased by the nano-anchoring effect.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.7.1-7.1
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• 2011

Nanoporous templates have been widely used for the development of new functional nanostructured materials suitable for electronics, optics, magnetism, and energy storage materials. We have prepared nanoporous templates by using thin films of mixtures of polystyrene-block-poly (methyl methacrylate) (PS-b-PMMA) and PMMA homopolymers. These templates have cylindrical nanoholes spanning the entire thickness of the film. Some applications of nanoporous templates are introduced: a) anti-reflective coating, b) the preparation of conducting polymer nanowires of poly (pyrrole), poly (3,4-ethylenedioxy-thiopene) onto a glass coated with indium-tin-oxide, and c) the separation membranes for biomaterials. We found that when the pore fraction of nanoholes in the film was ~0.68, almost zero reflectance at a specific wavelength, which can be changed with film thickness, was achieved at visible wavelengths Furthermore, ultra high density array of conducting nanowires was successfully prepared onto various substrates including flexible polymer. Due to highly alignment of polymer chain along the nanowire direction, the conductivity was much increased. Furthermore, these nanoporous films were found to be very effective for the separation of human Rhinovirus type 14 (HRV 14), major pathogen of a common cold in humans, from the buffer solution. We also found that when the pore size was effectively controlled down to 6 nm, a single file diffusion was observed.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.48-56
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• 2015

The film music in the 1940s is characteristic of its functional role of afterward crime movie and for expressed theme of scene to causing tension by encompassing the situational description of the scenes as well as psychological struggles of characters within the realm of musical techniques. This study demonstrates the process of change of theme music that expresses time-dependent plot development in Double Indemnity in which Miklos Rozsa participated as a music director and the result verifies the hypothesis that stimulate the senses and induces increased for the absorbed in the scene musical elements can be adopted as a symbolic means to emotions in movies.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.160-160
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• 1999

To reduce the fouling of heat exchangers, the plasma polymerized films was coated on the heat exchangers, and an effect of plasma polymerized film on fouling of heat exchangers was investigated. Monomer and reactive gases were used as the precursors of plasma polymerization. Plasma polymerized films were deposited with process parameters of pressure, power, and ratio of gases. Plasma polymerized films could be served as functional layers of good wettability and high resistance to corrosion. Wettability of plasma polymerized film could be controlled by the ratio change gas mixture. Hydrophilicity of plasma polymerized films on heat exchanger in air conditioner can provide improvement in performance of heat exchanger which results from good water drainage, decrease of pressure drop. DC-plasma polymerized films improve resistance to corrosion whcih is related to deposit formation in heat exchangers. The difference in the build up of fouling deposits between bare substrate and plasma polymerized substrate was investigated by scanning electron microscopy (SEM). An effect of plasma polymerized film on fouling of heat exchangers was discussed in terms of surface properties such as wettability, surface chemical state.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.129-132
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• 1999

A new single solution source MOCVD technique for the deposition of YBCO film has been developed, using a ultrasonic atomizer to feed the precursors into an evaporation zone. This method being investigated as a basis for future long wire fabrication, for example the electric power use, the magnatic applications, etc.. YBCO films were prepared on MgO(100) substrate, using mixture of Y, Ba, and Cu ${\beta}$ -diketonate chelate was dissolve in tetrahydrofuran as a solution sources. X-ray diffraction measurement indicated that the thin film grew epitaxially with the c-axis orientation perpandicular to the surface of the surface.

• Progress in Superconductivity
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• v.3 no.1
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• pp.120-124
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• 2001

To establish the deposition condition of YBCO thin film on MgO single crystal substrates, processing parameters of deposition temperature, chemical composition and oxygen partial pressure were controlled. When using a Ba-deficient composition of YB $a_{1.8}$ $Cu_3$$O_{x}$, non-superconducting phase like CuO, $CuYO_2$ were formed, but BaCu02 was formed together with Yl23 phase when the starting composition was Ba-rich ($YBa_{2.3}$ $Cu_3$ $O_{x}$). The epitaxially grown Yl23 phase was formed at 760-$810^{\circ}C$ and $P_{O2}$=0.29-0.91 Torr.r.r.r.

• Journal of the Korean institute of surface engineering
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• v.49 no.2
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• pp.178-185
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• 2016

In this study, we have fabricated light guide plates (LGPs) in thin film form for edge type back light unit (BLU) by using UV imprint lithography. In the LGPs, the pattern of functional resins on PC and PMMA substrates were successfully transferred from original master mold through PVC stamp. Optimized pattern arrays with slowly-sloped density were designed to obtain high brightness and uniformity. We could obtain a relatively improved brightness of $950cd/m^2$ and a uniformity of 87.3% by using the NP-S20 functional resins at an input power of 1.3 W because NP-S20 resin could show high formability after UV hardening process. The LGP prepared on polymethylmethacrylate (PMMA) substrate exhibited higher brightness than that on polycarbonate (PC) substrate because PMMA has lower refractive index resulting in more refraction toward the vertical direction.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.271-276
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• 2011

We investigated the possibility of introducing functional groups without damaging surface polymeric chains through the treatment of a polypropylene(PP) film immersed in liquid phase using an atmospheric pressure plasma with large area. The ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate: $[BMIM]^{+}[BF_{4}]^{-}$- was successfully applied for generating stable plasmas in the plasma-solution system. We successfully treated the film surface using the plasma-solution system and confirmed various oxygen-containing functional groups formed on the surface of PP film. The surface free energy of PP film was increased with increasing plasma treatment time and power. It also showed a maximum value at the PP sample treated in the ionic liquid solution of 1.5 M. ATR-FTIR analyses revealed the increase of various carbonyl groups(1,726 $cm^{-1}$, 1,643 $cm^{-1}$) and OH groups$(3,100{\sim}3,500\;cm^{-1})$ after plasma treatment of PP film, and XPS also supported the ATR-FTIR result.

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.59-64
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• 2009

This study investigated the surface characteristics of polylactic acid (PLA) film after one atmospheric pressure plasma treatment. We used de-ionized water and diiodomethane as polar and non-polar solvents, respectively, for measuring contact angles, and subsequently calculated the surface free energy of PLA film. The contact angle and free energy of PLA surface were optimized at the treatment time of 30 sec, RF-power of 70 W, Ar gas flow rate of 6 lpm and air exposure time of 5 min. We analyzed the change of chemical functional groups on the surface of PLA film through XPS and were able to observe the change of polar functional groups such as -C=O, -CO, -COO on the surface of PLA film after one atmospheric pressure plasma treatment.