• Korean Journal of Materials Research
• /
• v.24 no.7
• /
• pp.370-374
• /
• 2014

Inorganic pigments have high thermal stability and chemical resistance at high temperature. For these reasons, they are used in clay, paints, plastic, polymers, colored glass and ceramics. $CoAl_2O_4$ nano-powder was synthesized by reverse-micelle processing the mixed precursor(consisting of $Co(NO_3)_2$ and $Al(NO_3)_3$). The $CoAl_2O_4$ was prepared by mixing an aqueous solution at a Co:Al molar ratio of 1:2. The average particle size, and the particle-size distribution, of the powders synthesized by heat treatment (at 900; 1,000; 1,100; and $1,200^{\circ}C$ for 2h) were in the range of 10-20 nm and narrow, respectively. The average size of the synthesized nano-particles increased with increasing water-to-surfactant molar ratio. The synthesized $CoAl_2O_4$ powders were characterized by X-ray diffraction analysis(XRD), field-emission scanning electron microscopy(FE-SEM) and color spectrophotometry. The intensity of X-ray diffraction of the synthesized $CoAl_2O_4$ powder, increased with increasing heating temperature. As the heating temperature increased, crystal-size of the synthesized powder particles increased. As the R-value(water/surfactant) and heating temperature increased, the color of the inorganic pigments changed from dark blue-green to cerulean blue.

• Journal of the Korean Ceramic Society
• /
• v.44 no.5 s.300
• /
• pp.160-165
• /
• 2007

This research studied the most suitable synthesis condition of mineral pigments of black spinel, which have a stable chromogenic characteristic also ata high temperature of $1400^{\circ}C$ (it is not currently producedin the country) to meet not only functionality of ceramics but also an individual's aesthetic. It was synthesized by the plastic synthetic method on the basis of basic formation of $Fe_2O_3,\;Cr_2O_3$, Quartz, Kaolin, CoO, $MnO_2$, and plasticity was made at $1500^{\circ}C,\;1550^{\circ}C,\;1600^{\circ}C,\;1650^{\circ}C$. We researched the most suitable condition of plasticity and composition which make crystallization of spinel system and chromogenic characteristic close to black in every composition. And for the experiment of application to Zirconia, after adding synthesized pigments to Zirconia and plasticizing them, we analyzed their color and property of matters. The most suitable synthesis conditions of mineral pigments of black spinel system require composition of $Fe_2O_3-32.01%,\;Cr_2O_3-30.47%$, Quartz-9.66%, Kaolin-18.53%, CoO-3.71%, $MnO_2-5.62%$ and condition of plasticity kept for 1 h at $1600^{\circ}C$. When we added pigments synthesized in this way to Zirconia with 5 wt% and plasticized them at $1410^{\circ}C$, the result was that the degree of $strength-32.6kgf/mm^2$, absorptance-0.108%, $luminosity-L^*:37.54,\;color-a^*:1.31,\;b^*:2.61$ and their use suited for artificial jewelry or decoration Zirconia goods.

• The Journal of the Korea Contents Association
• /
• v.10 no.2
• /
• pp.193-201
• /
• 2010

Being an element of plastic arts and a language of plastic forms, the color white has significant potential for improving the quality of physical environment. Colors are dealt with scientifically in chromatics, and also often become an interesting topic when analyzing a society and its history and culture. Thus, an in-depth study of the symbolism of color white and, of white pigment are required because the color has not only an important chromatic value and this should be understood a great deal, but also been the important symbol of a culture in a particular period. This paper examined the significance of the color white identified in Asian and Western cultures based on scientific and psychological understanding of the color. This also analyzed a few major white pigments, then demonstrated different methods of using the pigments and various techniques of expression used by Asian and Western painters. In addition, the paper attempted to raise awareness of the color white as chromatic color over non-color by examining the contrasting viewpoints on the color, and the changes in the viewpoints over time and place.

• Corrosion Science and Technology
• /
• v.12 no.1
• /
• pp.1-6
• /
• 2013

Recently Digital TV industry has drastically been moving the illuminating system, which causes an obvious product change from PDP and LCD to LED model to provide high-definition image. Due to strong competition in the digital industry, TV manufacturers make a great efforts to reduce production cost by using low-priced materials such as steels instead of aluminum and plastic etc. In this paper we have developed a new low-priced electrogalvanized steel sheet, which has a black resin composite layer, to substitute conventional high-priced PCM steel and plastic mold for rear cover panel in the digital TV. The black resin composite was prepared by mechanical dispersion of the mixture solution that consists of high solid polyester resin, melamine hardener, black pigment, micronized silica paste, polyacrylate texturing particle and miscellaneous additives. The composite solution was coated on the steel sheet using roll coater followed by induction furnace curing and cooling. Although the coated layer has a half thickness compared to the conventional PCM steels having $23{\mu}m$ thickness, it exhibits excellent quality for the usage of rear cover panel. The new steel sheet was applied to test products to get quality certification from worldwide electronic appliance customers. Detailed discussion provides in this paper including preparation of composite solution, roll coating technology, induction curing technology and quality evaluation from customers.

• Development and Reproduction
• /
• v.18 no.2
• /
• pp.79-87
• /
• 2014

In Pleuronectiformes, blind-side malpigmentation (hypermelanosis) is common in cultured flatfishes, and is economically important. To understand the mechanism of blind-side hypermelanosis in flatfishes, we examined when the malpigmentation initially occurred, and studied how the symptoms proceeded during early development of the starry flounder, Platichthys stellatus. To assess quantitative pattern changes of blind-side skin, we observed morphological development of the whole body from 22 (total length [TL] $10.0{\pm}0.2$ mm and body weight [BW] $8.8{\pm}0.57$ mg) to 110 days (TL $23.4{\pm}0.7$ mm, BW $193.6{\pm}23.3$ mg) after hatching (DAH), and also examined the malpigmented area rate of blind-side skin and the malpigmented fish ratios. The experimental animals were reared in fiberglass-reinforced plastic (FRP) tanks in water at a temperature of $18.9{\pm}1.9^{\circ}C$ and salinity of $32.6{\pm}0.6$ psu and were fed with rotifer and Artemia nauplii from 22 to 48 DAH, and with A. nauplii and commercial feed from 49 to 110 DAH. As results, the first staining patch seen by the naked eye was observed around the area between the anus and pelvic fin or caudal edge of the trunk at 80 DAH (TL $20.6{\pm}0.5$ mm, BW $112.5{\pm}8.8$ mg). The pigmented area and the pigmented fish ratios were significantly increased from 80 to 110 DAH. These results indicated that malpigmentation on the blind side of starry flounder was initially observed at about 2 cm in length and 100 mg in weight, and the pigmented domain on the blind-side skin was continually broadened by the differentiation of pigmented cells (melanophores and xanthophores) with growth.

• Fashion & Textile Research Journal
• /
• v.21 no.6
• /
• pp.697-707
• /
• 2019

This review paper deals with materials, classification, and a current article investigation on smart textile sensors for wearable vital signs monitoring (WVSM). Smart textile sensors can lose electrical conductivity during vital signs monitoring when applying them to clothing. Because they should have to endure severe conditions (bending, folding, and distortion) when wearing. Imparting electrical conductivity for application is a critical consideration when manufacturing smart textile sensors. Smart textile sensors fabricate by utilizing electro-conductive materials such as metals, allotrope of carbon, and intrinsically conductive polymers (ICPs). It classifies as performance level, fabric structure, intrinsic/extrinsic modification, and sensing mechanism. The classification of smart textile sensors by sensing mechanism includes pressure/force sensors, strain sensors, electrodes, optical sensors, biosensors, and temperature/humidity sensors. In the previous study, pressure/force sensors perform well despite the small capacitance changes of 1-2 pF. Strain sensors work reliably at 1 ㏀/cm or lower. Electrodes require an electrical resistance of less than 10 Ω/cm. Optical sensors using plastic optical fibers (POF) coupled with light sources need light in-coupling efficiency values that are over 40%. Biosensors can quantify by wicking rate and/or colorimetry as the reactivity between the bioreceptor and transducer. Temperature/humidity sensors require actuating triggers that show the flap opening of shape memory polymer or with a color-changing time of thermochromic pigment lower than 17 seconds.

• Journal of Animal Environmental Science
• /
• v.15 no.2
• /
• pp.99-106
• /
• 2009

We conducted a comparison experiment of our wide-area spraying high speed fan with a fan which was developed by Japan MARUYAMA Inc. have been much recognized for it's history and skills in a field of spraying machine. In result, MARUYAMA Inc. fan sprayed up to 120 m and, on the other hand, wide-area spraying high speed fan of our own making was able to spray up to more than 160 m. Wide-area spraying machine have been supplied to domestic demands by importing from Japan, but it is determined to be possible that home products will occupy market for it's ability, price and A/S environment in future. The main research results are below. Some plastic cups which are in the open market are used for our experiment. After distributing 90 cups in a range of 10m vertically with localizing 5 cups horizontally and 18 cups vertically, spraying machine was moved and finally we make distribution charts by estimating the sprayed amounts on each cup. Vertical distance was set up to 5m and we calculated average values by using sprayed amount and data of 4 observers. In result our fan showed much sprayed amounts than MARUYAMA Inc. all over the field except situations of vehicle departing and stopping.