• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.5
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• pp.201-208
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• 2016

Ceramic pigments, which show good thermal and chemical stabilities, have been applied for various industry with development of digital printing technology. Ceramic inkjet printing has advantages of high efficiency of ink usage and eco-friendly process. Thus, the interest of the ceramic pigments with various function and color including CMYK (cyan, magenta, yellow, black) digital primary color is increasing. Here, we investigated the thermal and chemical stabilities of white ceramic pigment for digital inkjet printing process. The microstructure and crystal structure of MgO, $Al_2O_3$, $MgAl_2O_4$, $CeO_2$ were analyzed, and the stability with glaze were evaluated. In order to evaluate the applicability for digital inkjet printing, the chemical stability of white ceramic pigments at high temperature was investigated by characterization of the mixed color properties with CMYK ceramic pigments after firing process.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.1
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• pp.1-17
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• 2023

On painting cultural properties to which Orpiment, a traditional yellow mineral pigment, is applied, the color's degeneration is frequently observed. To identify the cause of the degeneration, this study takes a look into orpiment and the various pigments that are mixed into it (Lead White, Lead Red, and Cinnabar) in powder and painting state. The pigment was mixed with Argyo glue and then applied to korean traditional paper and silk. Considering the possibility that alum causes the discoloration, it was applied to the specimen. With a UV tester, the powders and the painted specimens were subjected to a light resistance test in three phases (96 hour). Color changes were measured with a colorimeter and minerals, chemical composition and structural changes were analysed by XRD, SEM/EDS and Raman spectrometers. While the color change of pure Orpiment powder according to the light resistance test was small, the colored specimen became darker. The color change was large in the Orpiment colored on the silk and in the alum-treated specimen. In Orpiment powder was produced white arsenolite as altered orpiment after UV test. In the mixed powder of Orpiment and Lead White were detected only the constituent minerals of Orpiment and Lead White, and no altered substances were produced. Whereas after the UV test, orpiment and arsenolite, which were altered substances of orpiment, and the constituent minerals of Lead White were detected. In the case of mixing the two pigments in the powder state, darkening did not occur even by the UV test. However, the specimens colored with the mixed powder were darkened by the UV test. The color change of Orpiment was different depending on the mixed pigment and base material. The color change was greater in the case of alum treatment than in the case without alum treatment, and it was found that alum also had an influence on the color change of Orpiment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.2
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• pp.11-18
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• 1982

The binder for hot mix type colored pavement must have the same physical qualities as the straight asphalt cement, but its color must not be dark-brown. We developed a kind of synthetic resin binder with light yellow color and confirmed its possibility as a binder for colored pavement through the several comparison tests between the straight asphalt cement concrete mixture and the mixture of binder and aggregate for colored pavement. For the pigment, it has been assured through tests that home products have the possiblities to be used. The binder has come to the stage of practical use through the trial mixing by asphalt mixing plant and the trial field placing. The mixing operation and the paving method of colored mixture are same as normal asphalt concrete mixture, but the quantity of pigment replaces that of mineral filler. The required content of pigment is decided by the trial mixing with other materials to be used.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.61-69
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• 1999

The dyeing experiments were done by using tannin pigments and herbs for natural fabrics such as ramie, hemp and silk. The anti-bacterial ability and color fastness were examined for dyed fabrics. Dye materials containing tannin pigment such as oak tree leaf showed rich dyeing on ramie, hemp, and silk fabrics when the pH of dye solution is lower as well as the dyeing temperature is higher. In crimson dyeing, the colour of fabric showed red-purple when the crimson pigment was extracted at 40$^{\circ}C$, while yellow-red when extracted above 70$^{\circ}C$. The colour fastness of dye materials containing tannin pigment was excellent showing 3~4 grade or above, while most of those derived from chinese medicine showed poor colour fastness of below 3 grade. The anti-bacterial ability of dye materials derived from chinese medicine was high, since the sappan wood fabric showed low bacteria reduction rate.

• Journal of Conservation Science
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• v.30 no.1
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• pp.13-25
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• 2014

This study interpreted the chemicals of the pigments and the coloring techniques employed on Youngsan Ritual Ceremony Buddhist Painting through a nondestructive analysis method and a microscopic observation. Based on the interpretation, this study closely examined the chemical properties of the names of the coloring materials specified on the ceremonial writing of the Buddhist painting. It is estimated that lead white was used for the white pigments, orpiment and organic pigment for the yellow pigment, cinnabar/vermilion, minium, red ochre, and red dyes for the red pigments, malachite or atacamite for the green pigments, azurite and indigo for the blue pigments, and ink stick for the black pigments. The pigment names specified on the ceremonial writing are juhong, jungcheong, hayeop, whangdan, and whanggeum, and it was verified that juhong is cinnabar or vermilion, jungcheong is azurite, hayeop is malachite or atacamite, whangdan is minium, and whanggeum is a gold foil.

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.187-194
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• 1989

Synthesis of spinel pigment on ZnO-Fe2O3 system. The object of this research is the synthesis of new spinel pigments on the basic of ZnO-Fe2O3 system which was substituted by ZnO-Fe2O3 by MgO-Al2O3. This research was progressed by measuring the X-ray diffraction and the reflectances of the substitued ZnO-Fe2O3 group. Which was obtained by sintering at the temperature of 1,00$0^{\circ}C$, 1,10$0^{\circ}C$, 1,20$0^{\circ}C$ and 1,25$0^{\circ}C$ and them by regrinding. In order to coloring test, here basic compositions of Barium glaze, Zinc glaze, Lime glaze, Lead glaze and Talc glaze used in this experiment are obtained from the ceramic work. Adding synthetic stains in these basic glazes with 3%, mixing and glazing on the specimen. The specimens was fired at 1,28$0^{\circ}C$ in reducing and oxidizing atmosphere in the gas kiln. The results of the research as follow. 1. Many kinds of spinel pigment was produced on ZnO-Fe2O3 system that is to say, not always only spinel. 2. Spinel peak was observed strongly on the ZnO-Fe2O3 system withsubstituting by MgO-Fe2O3 and MgO-Al2O3 group(the ratio of MgO, Al2O3 being increased, observed more strongly). 3. The most effective temperature ranges was 1,20$0^{\circ}C$~1,25$0^{\circ}C$. 4. The color of spinel pigments on this system was observed by "stable YR". 5. It was yellow red in oxidizing and green in reducing atmosphere on the coloring test.ring test.

• Journal of dental hygiene science
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• v.21 no.1
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• pp.38-44
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• 2021

Background: Dental caries and periodontal disease are bacterial infectious disease, mainly caused by plaque, a bacterial colony deposited on the tooth surface and gum tissue. Dental plaque disclosants easily stain the dental plaque, making them effective for scaling and tooth brushing education. As the erythrosine typically contained in dental plaque disclosants is highly cytotoxic, a low toxicity additive is needed. In this study, we aimed to examine the natural pigments with negligible cytotoxicity but can effectively stain the dental plaques for use in dental plaque disclosants. Methods: The pigmentation of eight types of natural pigments was tested on bovine tongue and teeth, as well as on head and neck tissue sections of experimental ICR mice. The cytotoxicity of gingival epithelial cells was measured via MTT assay. Pigmentation was performed on the bovine tongue and tooth surface. Pigmentation in the oral environment was observed in four mandibular incisors. A 2 Tone was used as a control. Results: Of the eight types of natural pigments, purple and blue pigments were effective in coloring dental plaques on the enamel surface as well as in the head and neck tissue sections. Additionally, purple and blue pigments were visible on the surface of the bovine tongue. Red, pink, orange, green, purple, and yellow pigments showed strong cytotoxicity, whereas brown and blue pigments had relatively low cytotoxicity. Blue pigment was effective in staining the dental plaque of four mandibular incisors. Conclusion: We suggest that the blue pigment derived from Gardenia jasminoides Ellis (Rubiaceae), which is effective for coloring dental plaques and has low cytotoxicity, is useful as a naturally derived dental disclosant.

• Journal of Conservation Science
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• v.35 no.6
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• pp.573-587
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• 2019

In this study, reproducing specimens were made from mixing domestically produced magnetite, clay and non-plastic raw materials to reproduce the pigments used in the manufacture of traditional cheolhwa buncheong stoneware. In order to reveal the color fomation of glaze, 30 specimens with good color development were analyzed scientifically. Magnetite, which is the main raw material of the pigment, is a pigment capable of creating a dark black color in a reducing environment at 1,200℃. However, it reacts with the additionally added lime component and discolors to greenish yellow color in oxidizing environment at 1,230℃. Hematite is not significantly affected by the firing temperature and environment, but develops a dark black color when mixed with clay with iron content of more than 10%. The fluidity of the pigment is determined by R₂O₃/RO₂ value, which also affects the color development. In the microtexture observation, the color formation of the glaze layer and the iron oxide crystals identified some differences depending on the particle size of the pigment and the firing environment. Reproduced specimens made of magnetite are present in the form of aggregates of iron oxide in the interface between glaze layer and slip layer in the oxidizing environment at 1,200℃. However, in the reducing environment, aggregates of iron oxides do not exist in the reproduced specimens, and they are homogeneously distributed in the glaze layer and formed a dark black color. In contrast, hematite-based specimens form dendritic structures in the glaze layer in an oxidizing environment and develop black.

• Journal of Life Science
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• v.18 no.9
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• pp.1219-1224
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• 2008

The embryonic zebrafish (Danio rerio) is rapidly becoming an important model organism for studies of early events in vertebrate development. Neural crest-derived pigment cell precursors of the embryonic zebrafish give rise to melanophores, xanthophores, and/or iridophores. Cell-signaling mechanisms related to the development of pigmentation and pigment pattern formation remain obscure. In this study, zebrafish embryos were treated with various signaling-related molecules - LiCl (an inositol-phosphatase inhibitor), forskolin (a protein kinase-A activator), a combination of LiCl/forskolin, and LiCl/heparin (an IP3 inhibitor) in order to identify the mechanisms involved in pigmentation. LiCl treatment resulted in ultrastructural and morphological alterations of melanophores. To identify the possible proteins responsible for this ultrastructural and morphological change, phosphorylation patterns in vitro and in vivo were analyzed. LiCl and LiCl/forskolin treatment elicited dramatic increases in the phosphorylation of a 55-kDa protein which was inhibited by heparin treatment. LiCl treatment also induced phosphorylation of a 55-kDa protein in melanophores purified from adult zebrafish. Collectively these results suggest that a LiCl-induced 55-kDa phosphoprotein plays a role in melanophore morphology and ultrastructure and ultimately effects gross pigmentation.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.330-343
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• 1997

Extraoral maxillofacial prostheses are essential for restoring facial structures that are lost as a result of congenital missing, injuries from accidents, surgical treatments of head and neck cancer. Recently, silicone is the most useful material for this purpose and is more advantageous than other maxillofacial prosthetic materials. However, there are some problems for long-term usage of silicone prostheses due to tear and color change. These are major contributing environmental factors to those problems that are such as ultraviolet light, cleansing agents, changes in humidity and successive adhesion and removal. The aim of this study is to evaluate the physical properties and color changes of maxillofacial prosthetic silicone material by those environmental factors using A-2186 silicone material (Factor II, USA) and two pigments, cadmium yellow medium and cosmetic red. Aluminium molds were fabricated according to the ASTM No. D412 & D624 specifications and resulted specimens from molds were fabicated and treated as follows. Control group and experimental I group were fabricated with 0.1% wt. pigment mixing in silicone elastomer and II-1 group, II-2 group of experimental II group were fabricated with 0.2%, 0.3% wt. pigment mixing in silicone elastomer, respectively. Control group was kept in darkroom at room temperature, I-1 group was kept under natural sunlight during 1week, I-2 group was soaked in 20% soap water during 1wk. I-3 group was successively adhered and removed 200 times on inner region of arm using Daro adhesive-33. Experimental II groups were kept in darkroom at room temperature. Instron universal testing machine was used to measure the % elongation, tensile strength, tear strength of control, experimental I, II groups and reflectance spectrophotometer(COLOR EYE-3000, Macbeth, USA) was used to measure the color differences between control group and experimental I group. The results were as follows : 1. When compared with control group, natural weathering group and 20% soap-water soaking group had no significant differences in % elongation(p>0.05). 2. 200 times successive adhesion and removal group, 0.2% wt. pigment group and 0.3% wt. pigment group had significant decreases in % elongation(p<0.05). 3. Natural weathering group, 20% soap-water soaking group and 200 times successive adhesion and removal group had no significant differences in tensile strength (p>0.05). 4. 0.2%, 0.3% wt. pigment groups had significant decreases in tensile strength(p<0.05). 5. Values of all experimental groups were decreased in tear strength. and 200 times successive adhesion and removal group had significant decrease in tear strength(p<0.05). 6. Natural weathering group and 20% soap-water soaking group had significant color differences(${\Delta}E$) and it could be detectable to naked eye(p<0.05). 7. Color differences between control group and 200 times adhesion and removal group were not detectable to the naked eye (${\Delta}E<1.0$).