• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.74-74
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• 1998

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.3
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• pp.105-110
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• 2015

The fiber-reinforced endodontic posts were prepared using a photocurable resin and a glass fiber. The mechanical property of the posts increased with increasing density of glass fiber and the micro-pores in the post were removed by a vacuum impregnation process. To improve the interfacial adhesion between glass fiber and polymer, silane coupling agent was used. The surface treatment of glass fiber increased the surface wettability of resing on glass fiber and increased the adhesion property with resin, consequently improved the mechanical property of posts.

• Journal of Periodontal and Implant Science
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• v.46 no.6
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• pp.362-371
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• 2016

Purpose: The increasing demand for esthetically pleasing results has contributed to the use of ceramics for dental implant abutments. The aim of this study was to compare the biological response of epithelial tissue cultivated on lithium disilicate ($LS_2$) and zirconium oxide ($ZrO_2$) ceramics. Understanding the relevant physicochemical and mechanical properties of these ceramics will help identify the optimal material for facilitating gingival wound closure. Methods: Both biomaterials were prepared with 2 different surface treatments: raw and polished. Their physicochemical characteristics were analyzed by contact angle measurements, scanning white-light interferometry, and scanning electron microscopy. An organotypic culture was then performed using a chicken epithelium model to simulate peri-implant soft tissue. We measured the contact angle, hydrophobicity, and roughness of the materials as well as the tissue behavior at their surfaces (cell migration and cell adhesion). Results: The best cell migration was observed on $ZrO_2$ ceramic. Cell adhesion was also drastically lower on the polished $ZrO_2$ ceramic than on both the raw and polished $LS_2$. Evaluating various surface topographies of $LS_2$ showed that increasing surface roughness improved cell adhesion, leading to an increase of up to 13%. Conclusions: Our results demonstrate that a biomaterial, here $LS_2$, can be modified using simple surface changes in order to finely modulate soft tissue adhesion. Strong adhesion at the abutment associated with weak migration assists in gingival wound healing. On the same material, polishing can reduce cell adhesion without drastically modifying cell migration. A comparison of $LS_2$ and $ZrO_2$ ceramic showed that $LS_2$ was more conducive to creating varying tissue reactions. Our results can help dental surgeons to choose, especially for esthetic implant abutments, the most appropriate biomaterial as well as the most appropriate surface treatment to use in accordance with specific clinical dental applications.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.537-542
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• 2011

Magnesium hydroxide as a non-halogen flame retardant has increasing attention due to its non-toxicity, high decomposition temperature and smoke suppressant ability during combustion. For the application of magnesium hydroxide retardant to the textile by soaking and coating method, the prerequisite for the coating is a small particle size, stable dispersion, and adhesion to the textile. The dispersion of $Mg(OH)_2$ particles and stability of the coating was checked by monitoring the change of transmittance and backscattering by varying the types of dispersion agents, binder, solvent, and $Mg(OH)_2$ source, and their compositions in the coating. The $Mg(OH)_2$ dispersion coating was applied to PET(poly(ethylene terephthalate)) non-woven textile. The physical properties are characterized by surface morphology, amount of coating, particle dispersion, and adhesion test. The flame retardant $Mg(OH)_2$ coated textile has been compared by limited oxygen index(LOI) and thermal gravimetry and differential scanning calorimetry(TG-DSC). It was found that phosphorous additive may give synergistic effect on $Mg(OH)_2$ flame retardant coating to make the flame retardant PET non-woven textile.

• Journal of the Korean Ceramic Society
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• v.53 no.1
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• pp.93-98
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• 2016

Cold plasma and heat treatment were selected as technologies to reduce unburned carbon in fly ash to less than 1.0%. Both cold plasma and heat treatment made it possible to eliminate unburned carbon to less than 1.0%. In the case of fly ash, which almost entirely eliminated unburned carbon with an ignition loss of 0.5%, heat treatment caused adhesion among particles and the BET specific surface area rapidly decreased as the mean particle size increased. On the other hand, with cold plasma, unburned carbon elimination caused the BET specific surface area to decrease and, as no adhesion occurred among particles, the mean particle size became small. Also, cold plasma treatment allowed small spherical particles confined within the unburned carbon particles to be released with the elimination of the unburned carbon frame, so that the quantity of fine particles had a tendency to slightly increase.

• Journal of the Korean Ceramic Society
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• v.31 no.7
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• pp.731-738
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• 1994

TiN films were deposited on high speed steels by plasma assisted chemical vapor deposition (PACVD), cathode arc ion plating (CAIP) and reactive magnetron sputtering (RMS). The properties of the films deposited by the three different methods were compared. The preferred oriented plane of PACVD-TiN is (200) and those of CAIP-TiN and RMS-TiN are (111). PACVD-TiN shows a dome surface and a microstructure having small grains. CAIP-TiN shows the highest microhardness and the best adhesion strength of the three because it has a dense microstructure and an ill-defined interface. But is shows the greatest surface roughness due to the Ti droplet created by the arc. RMS-TiN shows a microstructure having large voids so that its properties in microhardness and adhesion are the worst of the three.

• Journal of the Korean Ceramic Society
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• v.37 no.9
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• pp.927-932
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• 2000

Mg(NO$_3$)$_2$가 용해된 IPA 용액에서 형광 분말의 전기영동법에 의한 증착 과정을 증착 시간, Mg(NO$_3$)$_2$의 농도 및 열처리 조건에 따라 분석하였다. 전기영동법으로 가장 두께가 균일한 형광막을 얻기 위한 Mg(NO$_3$)$_2$의 최적 농도는 $10^{-3}$~$10^{-4}$ M였다. 형광체의 접착력을 향상시키기 위해 새로운 방법을 고안하였다. 즉 전기영동법으로 증착된 형광막에 B$_2$O$_3$가 용해된 IPA 용액을 분사한 후 열처리를 하였다. 그 결과 기존의 PL 특성을 그대로 유지하면서 접착력을 향상시킬 수 있었다. 그러나 CL 휘도는 약간 감소하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.529-532
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• 2005

The effects of polymer-binder ratio and ceramic powder content on the drying shringage and strength of polymer-modified pastes using redispersible polymer powders and ceramic powder are examined. As a result, the drying shrinkage of the polymer-modified pastes using redispersible polymer powders tend to decrease with increasing polymer-binder ratio and ceramic powder content. Regardless of the type of polymer powder, the tensile strength and adhesion in tension of the polymer-modified pastes with ceramic powder tend to increase with increasing polymer-binder ratio and ceramic powder content.

• Proceedings of the Korean Ceranic Society Conference
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• 2004.04b
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• pp.45.4-45.4
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• 2004

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.38.1-38
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• 2003