• 폴리머
• /
• 제32권5호
• /
• pp.433-439
• /
• 2008

고분자 소재에 평판형 플라즈마 전처리 방식을 적용시켜 polyurethane foam(density : 0.27)과 rubber (butadiene rubber) 소재 표면의 접촉각 및 접착력을 향상시켰다. 플라즈마 반응기의 최적의 반응조건을 조사하기 위해서 전처리기류(질소, 아르곤, 산소, 공기), 기류의 유량($30{\sim}100\;mL/min$), 그리고 전처리 시간($0{\sim}30\;s$) 등을 변화시켜 전처리하고 polyurethane foam의 경우 진공식 플라즈마처리 방식과 상호 비교하였다. 분위기 기류인 $N_2$의 유량을 100 mL/min로 설정 후 polyurethane foam은 10 s, rubber는 3 s 동안 전처리 했을 때 가장 높은 접착박리강도를 나타내었다. 전처리 후 소재의 표면 변화는 SEM과 ATR-FTIR을 이용하여 측정하였다. 결과적으로 평판형 플라즈마 조작 방식에 의한 처리로 소재 표면의 젖음성과 접착박리강도가 개선되었음을 확인하였다.

• Elastomers and Composites
• /
• 제39권1호
• /
• pp.3-11
• /
• 2004

플라즈마 표면처리는 표면 관능기 표면 활성도 등을 증가시켜 촉매적 선택성, 염색성 및 다양한 소재의 접착력을 증가시켜주는데 큰 역할을 담당한다. 본 연구에서는 dielectric barrier discharge (DBD)를 이용한 상압 플라즈마 토치로 ethylene-vinyl acetate (EVA)의 표면을 처리하였다. 이때 사용된 가스는 아르곤, 공기, 및 산소를 이용하였으며, 표면처리에 따른 EVA의 표면 특성을 제타전위와 표면자유에너지를 이용하여 관찰하였다. 그 결과, 상압 플라즈마 표면처리에 따른 EVA의 표면 관능기는 접착 에너지 ($G_{IC}$)와 비례관계를 가지며 증가하는 것을 확인하였다. 특히, 상압 플라즈마 표면처리 공정은 EVA와 polyurethane (PU) 계면의 접착력을 크게 증가시켜 주는 것을 확인하였다.

• 통합자연과학논문집
• /
• 제6권4호
• /
• pp.215-219
• /
• 2013

In this study, in order to investigate how consecutive treatments of glass surface with HF acid and water vapor/Ar plasma affect the quality of 3-aminopropyltriethoxysilane self-assembled monolayer (APS-SAM), poly(3,4-ethylenedioxythiophene) (PEDOT) thin films were vapor phase-polymerized immediately after spin coating of FeCl3 and poly-urethane diol-mixed oxidant solution on the monolayer surfaces prepared at various treatment conditions. For the film characterization, various poweful tools were used, e.g., FE-SEM, an optical microscope, four point probe, and a contact angle analyzer. The characterization revealed that a well prepared APS-SAM on a glass surface treated with water vapor/Ar plasma is very useful for uniform coating of FeCl3 and DUDO mixed oxidant solution, regardless of HF treatment. On the other hand, a bare glass surface without APS-SAM but treated with HF and water vapor/Ar plasma generally led to a very poor oxidant film. As a result, PEDOT films vapor phase-polymerized on APS-SAM surfaces are far superior to those on bare glass surfaces in the quality and electrical characteristics aspects.

• Medical Lasers
• /
• 제9권1호
• /
• pp.12-24
• /
• 2020

Human fibroblast-derived multi-peptide factors (MPFs) have been used during treatments with energy-delivering modalities to enhance energy-induced tissue reactions. Human fibroblast-derived MPFs, which include a range of growth factors and chemoattractive factors, activate and recruit fibroblasts and endothelial cells, as well as promote extracellular matrix deposition, all of which are crucial to wound repair. Interestingly, fibroblasts from different species or anatomical sites exhibit distinct transcriptional properties with high heterogeneity. In addition, the patterns of MPF secretion can differ under a range of experimental conditions. Therefore, the use of allogeneic fibroblasts and proper cultivation thereof are necessary to obtain MPFs that can enhance the epithelial-mesenchymal interactions during wound repair. Moreover, energy-delivering devices should be selected according to evidence demonstrating their therapeutic efficacy and safety on a pathological skin condition and the major target skin layers. This paper reviewed the histologic patterns of post-treatment tissue reactions elicited by several energy sources, including non-ablative and ablative fractional lasers, intense focused ultrasound, non-invasive and invasive radiofrequency, picosecond-domain lasers, and argon and nitrogen plasma. The possible role of the immediate application of human fibroblast-derived MPFs during wound repair was proposed.

• 한국식품영양학회지
• /
• 제31권2호
• /
• pp.301-307
• /
• 2018

In this study, a relatively effective process is used to sterilize Escherichia coli on the surface of micro-sized calcium citrate powder using nitrogen and argon as process gases in a low-temperature vacuum plasma treatment. The purpose of this study is to confirm and to introduce the effectiveness of homogeneous surface treatment for the sterilization of fine inorganic powder by the rotatable low-temperature RF plasma system designed by ourselves. The results of the test using 3M petrifilm showed that there were no remarkable spots in the case of the surface of plasma treated powder, whereas the untreated powder showed many blue spots, which indicating that the E. coli was alive. After 5 days, in the same samples, the blue spots were seen to be larger and darker than before, while the plasma-treated powder showed no changes. The results from FE-SEM analysis showed that the E. coli was damaged and/or destroyed by reactive species generated in the plasma space, resulting in the E. coli being sterilized. Furthermore, the sterilization effects according to the selected parameters ($N_2$ and Ar; flow rate 30 and 50 sccm) adapted in this study were mutually similar, regardless of such different process parameters, and this indicates that homogeneous treatment of powder surfaces could be more effective than conventional methods. Therefore, the plasma apparatus used in this study may be a practical method to use in a powerful sterilization process in powder-type food.

• Korean Chemical Engineering Research
• /
• 제48권5호
• /
• pp.556-560
• /
• 2010

부타디엔 고무 소재의 접착력을 향상시키기 위하여 대기압 표면개질방식을 적용시켰다. 평판형 플라즈마반응기의 최적의 반응조건을 구하기 위하여 반응기체(질소, 아르곤, 산소, 공기), 기체유량(30~100 mL/min), 플라즈마 처리시간(0~30초) 및 선처리제의 개질방법(GMA, 2-HEMA)을 변화시켜 실험하였다. 처리 전후의 소재의 표면변화는 SEM과 ATR-FTIR로 측정하였다. 기체의 유량과 처리시간이 증가함에 따라 접촉각이 감소하였고, 반응 기체는 공기로 유량 60 mL/min, 처리시간 5초 및 2-HEMA 첨가 선처리제를 사용하였을 때 최대의 접착박리강도를 나타내었다. 결과적으로 대기압식 평판형 플라즈마 처리방식으로 고무소재 표면의 젖음성과 접착박리강도가 개선되었음을 확인하였다.

• KSBB Journal
• /
• 제27권5호
• /
• pp.308-312
• /
• 2012

Argon-plasma jet (Ar-PJ) is generated by ionizing Ar gas, and the resulting Ar-PJ consists of a mixture of neutral particles, positive ions, negative electrons, and various reactive species. Although Ar-PJ has been used in various biomedical applications, little is known about the biological effects on cells located near the plasma-exposed region. Here, we investigated the effects of the Ar-PJ on actin cytoskeleton of mouse embryonic fibroblasts (MEFs) in response to indirect as well as direct exposure to Ar-PJ. This Ar-PJ was generated at 500 mL/min of flow rate and 100 V electric power by our device mainly consisting of electrodes, dielectrics, and a high-voltage power supply. Because actin cytoskeleton is the key cellular machinery involved in cellular movement and is implicated in regulation of cancer metastasis and thus resulting in a highly desirable cancer therapeutic target, we examined the actin filament architectures in Ar-PJ-treated MEFs by staining with an actin-specific phalloidin labeled with fluorescent dye. Interestingly, the Ar-PJ treatment causes destabilization of actin filament architectures in the regions indirectly exposed to Ar-PJ, but no differences in MEFs treated with Ar gas alone and in untreated cell control, indicating that this phenomenon is a specific cellular response against Ar-PJ in the live cells, which are indirectly exposed to Ar-PJ. Collectively, our study raises the possibility that Ar-PJ may have potential as anti-cancer drug effect through direct destabilization of the actin cytoskeleton.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.544-545
• /
• 2013

Recently, low-temperature atmospheric-pressure plasmas have been investigated [1,2] for biomedical applications and surface treatments. Experiments for improving hydrophilicity of stainless steel (SUS 304) plate with atmospheric microwave argon and H2O2 mixture plasma jet [3] were carried out and experimental measurements and plasma simulations were conducted for investigating the characteristics of plasma for the process. After 30 s of low power (under 10 W) and low temperature (under $50^{\circ}C$) plasma treatment, the water contact angle decreased rapidly to around $10^{\circ}$ from $75^{\circ}$ and was maintained under $30^{\circ}$ for a day (24 hours). The surface free energy, calculated from the contact angles, increased. The chemical properties of the surface were examined by X-ray Photoelectron Spectroscopy (XPS) and the surface morphology and roughness were examined by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) respectively. The characteristics of plasma sources with several frequencies were investigated by Optical Emission Spectroscopy (OES) measurement and one-dimensional Particle-in-Cell (PIC) simulation and zero-dimensional global simulation [4]. The relation between plasma components and the efficacy of the surface modification were discussed.

• 한국염색가공학회지
• /
• 제1권1호
• /
• pp.7-18
• /
• 1989

The distinguishing characteristic of the glow discharge is that chemical reaction induced by partially ionized gases are limited only to the substrate surface. Most studies have been done on the plasma etching and polymerization. The graft polymerization in vapour phase by cold plasma has been rarely investigated. In this study the system of tub3ar reaction chamber with capacitively coupled electrode of alternative current of 60 Hz was employed for the graft polymerization. The graft polymerization of Acylic Acid(AA) onto the poly (ethylene terephthalate) (PET) was carried out by treatment of PET film and fabric by cold plasma (glow discharge of argon gas), followed by the supply of AA vapour. The graft yield was about 1 wt%. The surface property was determined by contact angle, the surface tension was evaluated by zisman’s plot and equation of surface tension mesurement. The results were as follows: 1. In order to obtain lower contact angle, it was effective to avoid the vicinity of electrodes for a setting position of substrate. 2. Contact angle affected on the monomer pressure and its duration of exposure to the acid vapour. 3. Polymer radical formation was influenced by the changes of the value of current density and plasma treatment time. 4. Total surface tension of plasma grafted PET film increased. With an increase in the carboxylic acid content, the dispersion force decreased, while, the polar force and hydrogen bonding force increased. 5. The contact angle decreased from $75^\circ$ to around $30^\circ$ by plasma grafting. There was no ageing effect on the contact angle after 4 months.

• 한국표면공학회지
• /
• 제47권5호
• /
• pp.227-232
• /
• 2014

In this study, we propose the application of doping process technology for atmospheric pressure plasma. The plasma treatment means the wafer is warmed via resistance heating from current paths. These paths are induced by the surface charge density in the presence of illuminating Argon atmospheric plasmas. Furthermore, it is investigated on the high-concentration doping to a selective partial region in P type solar cell wafer. It is identified that diffusion of impurities is related to the wafer temperature. For the fixed plasma treatment time, plasma currents were set with 40, 70, 120 mA. For the processing time, IR(Infra-Red) images are analyzed via a camera dependent on the temperature of the P type wafer. Phosphorus concentrations are also analyzed through SIMS profiles from doped wafer. According to the analysis for doping process, as applied plasma currents increase, so the doping depth becomes deeper. As the junction depth is deeper, so the surface resistance is to be lowered. In addition, the surface charge density has a tendency inversely proportional to the initial phosphorus concentration. Overall, when the plasma current increases, then it becomes higher temperatures in wafer. It is shown that the diffusion of the impurity is critically dependent on the temperature of wafers.