• Journal of the Korean Ceramic Society
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• v.47 no.3
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• pp.249-255
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• 2010

To investigate optical properties of (V, Pr)-doped $ZrSiO_4$ green pigments, samples were prepared by the ceramic method using NaF and NaCl as mineralizers. They were characterized by X-ray diffraction, UV-Vis spectroscopy and Raman spectroscopy. The changes of color in the samples during heating and effect of mineralizers were studied in terms of valence of the vanadium and praseodymium in the zircon matrix. (V, Pr)-doped $ZrSiO_4$ pigments give rise to green coloration in $800^{\circ}C$. The oxidation state of V and Pr ions of pigments in the glazed samples were confirmed by UV-Vis absorption spectra. This absorption spectra showed three typical bands of trivalent Pr at the 445, 480~490, 592 nm due to f-f transitions and two broad bands of 302~380, 400~500 nm due to f-d transitions of tetravalent Pr. According to the increasing amounts of $Pr_6O_{11}$, the two broad bands showed decreasing intensity at 290, 640 nm due to d-d transitions of tetravalent V.

• Fashion & Textile Research Journal
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• v.11 no.2
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• pp.337-343
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• 2009

This study systematically investigated a method for extraction of safflower (Carthamus tinctorius Linnaeus) colorants by ultrasonic treatment. Compared to pigments productivity and cell wall structures of safflower after general and ultrasonic method, the ultrasonic method showed high extraction efficiency of safflower pigments due to destruction of safflower cell wall caused by high vibration energies. Microscopic analysis confirmed the hypothesis that the ultrasonic treatment of safflower caused its cell wall structure loosened and made efficient extraction of safflower pigments. And also, LC-MS/MS analysis revealed that productivities of the yellow and red safflower pigments by ultrasonic method were 21.9% and 14.6% higher, respectively, than those of pigments extracted by general method. The ultrasonic extracted yellow and red colorants could be used to dye not only natural fibers like cotton, silk and wool, but also synthetic fiber like nylon, and generally gave a better color tone than the general extracted colorants from safflower due to the affinities of red and yellow colorant on different fibers. As the yellow and red colorant were extracted by ultrasonic treatment in water, the K/S value on of 550/440nm of cotton and rayon was increased but in the case of silk and wool the change of this value was almost not detected. Finally, this technique might provide a solution to establish reproducibility and standardization for the extraction and dyeing methods on fabrics.

• Journal of Conservation Science
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• v.27 no.3
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• pp.269-276
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• 2011

We have suggested effective P-XRF analysis method for pigment painting layer by calculating penetration depth of X-ray. This experiment calculated that X-ray generated from P-XRF was possible penetration until 1.17mm deep in the pigment painting. Based on the experimental results, analysis for eight color pigments on wall paintings in Ssanggyesa Main Hall, most pigments were painted traditional pigments. However pigments on recently restorated wall painting were used synthetic modern pigments.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.72-74
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• 2004

The color change of lead-containing pigments is one of the most serious diseases in watercolor, oil paintings and wall paintings. These pigments have a tendency to darken or brighten. It was proved that oxidation of lead containing pigments in the formation of brown-colored lead dioxide is a photochemical reaction under high humidity conditions. Therefore, we carried out some analogic experiments on the color change of three typical lead containing pigments ; $Pb_3O_4$, Pbo and $PbCo_3{\cdot}Pb(OH)_2$ at the conditions of illuminations under the high humidity ($2PbCo_3{\cdot}Pb(OH)_2$ R. H.). The reason for the chemical reactions are discussed and the results of these experiments are shown in some spectrograms, micrographs and X-ray micro-diffraction patterns. Important conclusions were drawn in our research. Due to the formation of brown $PbO_2$, red lead $(Pb_3O_4)$ and massicot (PbO) turned brown or dark when they were illuminated light under high humidity. We noticed that the brightening of red lead occurred d to admixture with chalk or lead white in egg yolk or linseed oil medium on exposure to light. Lead white used in oil paintings turned yellowish on dark.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.682-688
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• 2009

Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heat treatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at $55^{\circ}C$, while the brightness and yellowness changed a little. Significant increase in 'a' and 'b' values of tea liquor was observed at $95^{\circ}C$. Color change of liquor at $55^{\circ}C$ was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, and an increase in the pheophytins and ${\beta}-carotene$ levels. However, all pigments except ${\beta}-carotene$ decreased with time extension at $95^{\circ}C$. Significant correlation was found between pigments and color difference index. The browning of fresh green tea liquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of $Zn^{2+}$ at 1.6 ${\mu}mol/L$ could partially alleviate the decrease in greenness during heat treatment.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.1-5
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• 2003

This study was carried out to investigate the anthocyanin pigments in the fruits of mulberry and grape. The anthocyanin pigments in the fruits of mulberry and grape were extracted with l% methanolic hydrochloric acid. The cyanidin-3-glu-coside (C3G) was separated and quantified by HPLC system using a Nova-Pack C$\sub$18/ column. The cyanidin-3-glucoside (C3G) contents of mulberry fruits were higher than that of grapes. Especially, anthocyanin pigments of mulberry fruits showed only C3G peak, but anthocyanin pigments of grapes showed some species peaks.

• Korean Journal of Metals and Materials
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• v.49 no.5
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• pp.367-373
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• 2011

This paper studies the experimental method that uses the homogeneous precipitation method to prepare mica flakes coated with anatase-type titania pearlescent pigment with urea as precipitant. The optimum technology parameters, the chemical composition, the microstructure, and the color property of resulting pigments are discussed. The coating principle of mica coated titania with various coating thickness is analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy(TEM) and tested by spectrophotometer analysis. The colored nanocrystalline pigments with different morphology and coating thickness 45-170 nm were prepared by homogeneous precipitation treatment of $TiOSO_4$(titanum oxysulfate) aqueous solutions. Characterizations on the pigments show that the pearlescent effects of the pigments depend mainly on mica size, thickness of the metal oxide deposit, its chemical composition, and crystal structure.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.197-199
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• 2002

Samples of enamel wear for kitchen works were made at the Kordco Enamel Co. We analyzed the colors of enamel wears with Color Meter (JS555). The colors of enamel wears could be controled by mixing ratio of frits and pigments. Many kinds of frits and pigments were tested, and colors of enamel wears could be changed by variable frits. Colors were weakly changed by several mixing ratio of pigments.

• Journal of Plant Biotechnology
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• v.1 no.2
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• pp.69-77
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• 1999

Safflower is an important medicinal plant that has been used in China, Korea and Japan for thousands of years. The red and yellow pigments obtained from the petals of safflower can invigorate blood, release stagnation and promote menstruation. In addition, these pigments are used safely in processed foods and soft drinks as naturally harmless rotor additives. On the other hand, the seed of safflower contains 30-40% oil with higher level of mono- and poly-unsaturated fatfy acid profiles and elevated levels of $\alpha$-tocopherol. In this paper, we describe advances in the production of pigments and $\alpha$-tocopherol by cell culture in safflower.

• Journal of the Korean Ceramic Society
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• v.45 no.8
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• pp.453-458
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• 2008

New inorganic red pigments based on Cr-doped $Y_2O_3$ and $Al_2O_3$ were synthesized by solid state method and characterization of their pigments were characterized by using XRD, FT-IR, SEM and UV-Vis spectrophotometer. The single perovskite phase revealed at $1450^{\circ}C{\sim}1550^{\circ}C$ for 6 h due to using mineralizers. The color of pigment powders resulted out various red-shades depending on the compositions of used materials and temperatures. Glazed tiles painted with pigment powders showed red color in oxidation and reduction firing. The best red colour was obtained when the $Cr_2O_3$ was used 0.04 mole at $1450^{\circ}C$ for 6 h.