• The Journal of Advanced Prosthodontics
• /
• 제8권1호
• /
• pp.16-20
• /
• 2016

PURPOSE. Polymer infiltrated ceramic network (PICN) materials, also called hybrid ceramics, are new materials in dental market. The manufacturer of the PICN material VITA Enamic suggests 3 different finishing procedures for this new material. In the present study, surface roughness and color differences caused from different finishing procedures of VITA Enamic were investigated. MATERIALS AND METHODS. 120 specimens were prepared in dimensions $2{\times}10{\times}12mm$ from VITA Enamic hybrid ceramic blocks with 'high translucency' and 'translucency 2M2' shades. The specimens were divided into 8 groups. For each group, different finishing procedures suggested by the manufacturer were performed. Surface roughness values were determined by a tactile portable profilometer. Color changes were evaluated using a clinical spectrophotometer. The data were analyzed using one-way ANOVA and Tukey's post-hoc comparison. The significance level was set at ${\alpha}=0.05$. RESULTS. The roughest surfaces were observed in Glaze Groups. Their surface roughness values were similar to that of the control group. Clinical Kit and Technical Kit groups did not show a statistically significant difference regarding surface roughness (P>.05). The largest color difference regarding ${\Delta}E_{00}$ was observed in Clinical Kit finishing groups. There were also statistically significant color changes between the groups (P<.05). However, all the groups showed clinically acceptable color change (${\Delta}E_{00}$<2.25) except Clinical Kit Groups (${\Delta}E_{00}$>2.25). CONCLUSION. Within the limitations of the present study, it may be suggested that finishing the VITA Enamic restorations by Technical Kit instead of Glaze and Clinical Kit gives better clinical performance in regard to surface roughness and shade matching.

• 한국세라믹학회지
• /
• 제47권4호
• /
• pp.312-318
• /
• 2010

Chulwha pieces collected from Hakbong-ri site in Keryong mountain were studied whether there is reactions or not in each layer to investigate firing condition of glaze, body, Chulwha, engobe of Buncheong ware in the early Chosun Dynasty, 15th~16th Century. As a result of XRD analysis of a Chulwha piece, a main crystal phase was $\alpha$-Quartz and a second was Mullite. It was assumed the firing temperature would be around $1200^{\circ}C$ because a little amount of Mullite was formed in the body and there was no phase transition $\alpha$-Quartz to cristobalite. As a result of ICRM analysis, Chulwha and glaze didn't react and the melted glazes were sunk into the Chunwha particles. The thin layer of glaze was found on the Chulwha layer. As a result, the color of Chulwha layer always came to vivid black. Moreover, Chulwha painting didn't spread over the Buncheong ware, because Chulwha and engobe didn't react. The boundary interface of engobe and body was not clear because they had similar compositions. This shows engobe was composed of more $Al_2O_3$ than body.

• 한국세라믹학회지
• /
• 제48권4호
• /
• pp.298-302
• /
• 2011

This study developed a pigment by doping Cr to Pyrochlore-type stannate crystals and investigated the chromogenic relationship in a glaze. Crystal phases of the pigment according to firing temperatures were analyzed by XRD, and the doping relationship was analyzed by Raman Spectroscopy. Color and reflection rate of the pigment were measured by UV-vis Spectrophotometer. Consequently, stannate characteristic band appeared at 307, 408, 505 and $755cm^{-1}$ until 0.1 mole substitution of $Cr_2O_3$. However, as amount of $Cr_2O_3$ increased, the stannate characteristic peak was decreased and shift happened at the left hand side due to Cr-dope. In composition of 0.12~0.14 mole substituted, the unreacted $Cr_2O_3$ stannate characteristic peak, which was not engaged, was shown. This result shows the maximum limit of solid solution was 0.1 mole $Cr_2O_3$. The color of the glaze, which was produced by adding 6 wt% of $Y_2Sn_{1.94}Cr_{0.06}O_7$ pigment in a lime or a lime-magnesia glaze and fired the mixture at $1260^{\circ}C$, was grayish pink with $L^*$ 70.29, $a^*$ 5.68 and $b^*$ 6.27. It showed gray with $L^*$ 68.82, $a^*$ 3.07and $b^*$ 8.13 for $Y_2Sn_{1.9}Cr_{0.1}O_7$.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2013년도 춘계학술대회 논문집
• /
• pp.180-180
• /
• 2013

Ceramic glaze has been developed by numerous experiences and knowhow of potters for a long time. It has offered curiosity and beauty to many people with a variety of colors. This study first verifies the color difference according to clays and glazing used for the coloration experiment based on generation process and chemical reaction of cobalt sulfate, and determines the effect of a dilution ratio with water on changes in coloration concentration. The cobalt-aluminate spinel and the cobalt-silicate olivine are the strongest of the ceramic pigment, producing a very pure, navy blue color.

• 대한안전경영과학회지
• /
• 제9권6호
• /
• pp.197-204
• /
• 2007

Ceramic pigments were developed by using 4 kinds of Brass scraps. Each Brass scraps were mixed with same weight-ratio of Husk ash, and fine-ground by Rotate ring mill(RRG-120, Armstech industrial. co. Ltd, Korea) after firing at $900^{\circ}C$, $1000^{\circ}C$ and $1100^{\circ}C$. As a result, analysis of particle size of synthetic pigments by particle size analyser, they are $3{\mu}m$ as average. The resulting pigments were characterized by using XRD, FT-IR, SEM Structure of the crystals are Zn2SiO4,, and ZnO, Cu2O, CuO, and cristobalite are existed and particles' shape are plate or needle. As a result of analysis of chemical composition by XRF, synthetic pigments have high SiO2 and CuO content and have SnO2, ZnO and NiO, too. 1wt%, 3wt% and 5wt% pigments were added in each lime glaze, lime-barium glaze and lime-magnesia glaze, and fired at oxidation and reducing atmosphere to figure hue in glazes out. As a result of analysis of color, chroma and brightness by UV, colors of glazes fired at oxidation atmosphere turned into green from sky blue, and colors of glazes fired at reducing atmosphere turned into pink and red.

• 보존과학회지
• /
• 제38권4호
• /
• pp.301-313
• /
• 2022

We made a Korean white porcelain or Joseon Baekja jar and based on the raw materials used and reproductions of each stage, we aimed to compare and analyze the physicochemical changes of the raw materials such as clay at each manufacturing stage, as well as identify the characteristics and correlations. Although the basic main components of clay and glaze material are similar, their texture becomes denser in the process of bisque firing pottery (Chobeol-pyeon) and glaze firing pottery (Jaebeol-pyeon), and we confirmed that in addition to the tendency of increasing vitrification, low-temperature minerals such as mica and illite gradually disappeared, while high-temperature minerals such as cristobalite were newly created. This phenomenon has also been verified by the rapid decrease in absorption rate while the change in specific gravity was small. In addition, the color was greatly affected by the firing atmosphere, and the yellow-red chromaticity of the raw materials was higher during bisque firing but showed a rapidly decreasing characteristic during glaze firing. The value of magnetic susceptibility, which is related to iron (Fe) component, showed a tendency to decrease in glaze firing pottery. CT images were confirmed as a method that can indirectly estimate the change in the material properties of the object step-by-step for the entire object. In conclusion, the study of manufacturing stages of reproduction can provide basic data for scientific research on the estimation of porcelain and pottery making technology and changes in raw materials.

• 한국산학기술학회논문지
• /
• 제14권6호
• /
• pp.3102-3107
• /
• 2013

$Al_2O_3$, CoO, $Cr_2O_3$, ZnO, $SrO_2$ 및 Kaolin을 이용하여 무기안료를 제조하였다. 제조방법은 원료분말들을 일정비율로 배합하고 분쇄한 후 소성을 시키고 분쇄 및 건조과정을 거쳐 제조하였다. 안료의 원료 중 $Cr_2O_3$의 비율이 증가할수록 청색에서 녹색으로 발현되는 것을 알 수 있었으며 안료의 조성에 관계없이 소성시킨 안료의 입자크기가 작아질수록 색도가 밝아지는 것을 알 수 있었다. 그리고 소성시 최고온도는 $1,250^{\circ}C$정도가 가장 적합한 것으로 조사되었다. 안료의 유약적합성 실험에서는 안료 성분 중 $Cr_2O_3$의 비율이 증가할수록 녹색에 가까워졌으며 CoO의 비율이 증가할수록 청색감이 증가하였다.

• 헤리티지:역사와 과학
• /
• 제50권4호
• /
• pp.20-37
• /
• 2017

북제시기 유도 중에는 흰색 혹은 옅은 황색 유약 바탕에 녹색, 갈색, 황색 등으로 채색한 것이 있는데, 이는 "채회유도(彩繪釉陶)"로 통칭된다. 1971년 하남성(河南省) 안양시(安陽市) 홍하둔촌(洪河屯村)에 소재한 범수묘(範粹墓)에서 백유녹채삼계관(白釉綠彩三系罐)과 백유녹채장경병(白釉綠彩長頸甁)이 출토되었으나, 연구자들의 주목을 받지 못한 채 공반 출토된 백유기(白釉器)만이 중국에서 기년 자료가 확실한 가장 이른 백자의 증거로 제시되어 끊임없는 논쟁이 이루어졌다. 필자는 이 채회유도에 주목하여, 지금까지 무덤과 가마터에서 발견된 자료들을 정리하였으며, 이를 바탕으로 장식특징과 제작 기술을 파악하였다. 또한 이들이 부장된 무덤의 연대를 통한 출현 상한시점 및 피장자의 신분을 특정하여 채회유도의 사회적 가치를 알아보았다. 북제시기 채회유도는 이전 시기와 구별되는 제작특징이 확인되었는데, 구체적으로는 자토(瓷土)를 이용한 태토, 2차 소성, 유상회채(釉上繪彩) 기법이 새로 채용되었다. 이러한 특징은 이미 북위(北魏) 시기 유도에서 일부 나타난 변화로, 이것이 북제까지 이어져 백유 채회유도의 출현으로 나타났다고 볼 수 있다. 또한 채회유도의 기형은 동시기 남방지역 자기 기형과 북위시기 이래 생산된 채회의 속성이 결합되어 형성되었음을 확인하였다.

• 한국세라믹학회지
• /
• 제51권3호
• /
• pp.184-189
• /
• 2014

Electric arc furnace dust (EAFD) is a solid waste generated by the steel-scrap recycling process. It mainly consists of zinc oxides (ZnO), alumina ($Al_2O_3$), iron oxides ($Fe_2O_3$), and silica ($SiO_2$). Here we report the preparation and characterization of blue ceramic pigments using EAFD powder as a starting material. $(Zn(EAFD),Co)Al_2O_4$ blue ceramic pigment was prepared by the solid-state reaction method. The color characteristics of the pigment obtained were compared with those of pure $CoAl_2O_4$. The new pigment was characterized using XRD, CIE-$L^*a^*b^*$ color-measurements, SEM, and EDX. The XRD analysis revealed that the $(Zn(EAFD),Co)Al_2O_4$ pigment was composed of mainly the spinel phase of $(Zn,Co)Al_2O_4$. The $Zn(EAFD)_{0.25}Co_{0.75}Al_2O_4$ pigments showed a vivid blue color with a $b^*$ value of -28.64 and a good glaze stability with a transparent glaze.

• 한국세라믹학회지
• /
• 제15권2호
• /
• pp.66-71
• /
• 1978

The cobalt blue spinel stains (main composition; CoO:$Al_2O_3$=1 : 1) in CoO-NiO-$Al_2O_$3 and $CoO-Al_2O_3-Cr_2O_3$ system were prepared by the calcination of each component oxides to be adequate for the factory. The color development, the change of the lattice constnat of the spinel and its application to colored glazes were studied. The results were summarized as follows. 1) In CoO-Al_2O_3$ spinel, the excess addition of each component hardly made any variation in lattice constantand alumina-rich spinel specimens caused the brilliant blue color fade. 2) An increase of $Ni^{2+}$ in $CoO-NiO-Al_2O_3$ system, made the lattice constnat of the $CoO-Al_2O_3$ spinel smaller, and an increase of $Cr^{3+}$ in $CoO-Al_2O_3-Cr_2O_3$, larger. 3) Glazed stains under lead glaze were colored nearly same dark blue color fade.