• Journal of the Korean Wood Science and Technology
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• v.14 no.1
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• pp.55-60
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• 1986

Discoloration sensitivities of woods grown in this country haven't reported yet. Therefore we examined discoloration sensitivities of domestic wood specimens to iron (0.1 %, $FeCl_3.6H_2O$), alkali (pH 12.0, NaOH). acid (pH 1.0, $C_2H_2O_4$) and exposing to sunlight (40 hrs), Thirty-six hardwood species were collected and examined. All specimens were prepared from heartwoods of the collected species. But the specimens of 4 Betula species were divided into sapwoods and heartwoods. By iron stain, the color differences (${\Delta}E$) of 21 wood specimens including one Betula sapwood showed above 12.0, which means strong discoloration sensitivities, and of 3 specimens including one Betula sapwood showed below 2.5, which means weak discolorations. The most strong iron discoloration species was Jungkukgulpi-namu (Pterocarya stenoptera). By alkali stain, the color differences (${\Delta}E$) of 3 wood specimens showed above 9.0, which means strong discoloration sensitivities, and of 18 wood specimens including 4 Berula sapwoods showed below 2.5, which means weak discolorations. By acid stain, the color differences (${\Delta}E$) of 6 wood specimens showed above 10.0 which means strong discoloration sensitivities, and of 12 wood specimens including one Betula sapwoods showed below 2.5, which means weak discolorations. By exposing to sunlight, the color differences (${\Delta}E$) of 31 wood specimens including one Betula sapwoods showed below 6.5, which means, strong discoloration sensitivities, and of only one specimens showed below 2.5, which means weak discoloration. The most strong discoloration species by exposing to sunlight was Guirung-namu (Prunus padus). In general, it was shown that hardwoods grown in Korea were most subject to change of color by exposing to sunlight and next were by iron stain. Domestic hardwoods showed some differences in discoloration sensitivities from domestic softwoods previously reported.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.1
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• pp.105-113
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• 2001

The purpose of this study is to compare effects of denture cleansers and disinfectants on the color. surface hardness, and surface roughness of reinforced acrylic resin using polyhedral oligosilsesquioxane molecules(POSS resin) to those of common resins. According to manufacturer's instructions, 45 specimens were made from three denture resins(Luciton 199, Paladent 20, POSS resin), and polished. Five denture cleansers(distilled water, glutaraldehyde, alkaline hypochlorites, chlorhexidine, alkaline peroxides) in combination with three denture resins were evaluated before and after immersion for 7 days. Color data in $L^*a^*b^*$ system were measured with a colorimeter. Surface hardness data were measured with a microhardness tester. Surface roughness data were measured with a 3-dimensional surface analyzer. Data were analyzed with two-way ANOVA, one-way ANOVA, and t-test. The results were as follows : 1. All resins(Luciton 199, Paladent 20, POSS resin) showed significant differences in color after immersion in hypochlorites(p<0.05). 2. POSS resin showed significant differences in color compared with Paladent 20 in all denture cleansers, but no statistically significant differences with Luciton 199(p<0.05). 3. Luciton 199 showed significant differences of surface hardness in chlorhexidine, Paladent 20 showed significant differences in glutaraldehyde and chlorhexidine. POSS resin showed a little change of surface in all denture cleanser, but no statistically significant differences(p<0.05). 4. Luciton 199 and Paladent 20 showed significant differences of surface roughness in hypochlorites and glutaraldehyde, and POSS resin showed no statistically significant differences in all denture cleansers(p<0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.2
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• pp.191-202
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• 2007

Statement of problems: Long-term success of esthetic restorations, depends on various factors, especially on color stability of the restorations. The color stability is affected by resin cements beneath the porcelain laminate veneers. Purpose: The purpose of this study was to comprehend the color stability of resin cements by comparing with 4 different kinds of resin cements (Choice, Variolink II, Nexus 2, Rely-X). Material and methods: Porcelain laminate disk samples were luted with resin cements. After thermocycling of each 1000, 2000 and 3000 cycle, specimens were measured by spectrophotometers and the color differences were. Results: 1. After thermocycling of 1000, 2000 and 3000cycle, color difference, $({\Delta}E^*)$ of all specimens were incresed, but were not statiscally significant differences. 2. In the Choice of A1 shade and the Nexus 2 of A3 shade, color difference$({\Delta}E^*)$ after thermocycling of 3000cycle was $incre^*ased$ significantly than after thermocycling of 1000cycle. However, other groups did not show any statistically significant differences (P<0.05). 3. After thermocycling of 3000cycle, color difference$({\Delta}E^*)$ between A1 shade and A3 shade of Nexus 2 showed statistically significant difference. However no statistically significant differences were observed in other groups (P<0.05). 4. The mean of color difference$({\Delta}E^*)$ is 1.0-2.06 after 3000 thermocycling and the data were ranked in the ascending order of Variolink II, Nexus 2, Choice and Rely-X in A1 shade group and Choice, Rely-X, Variolink II and Nexus 2 in A3 shade group. Conclusion: Above results revealed that, after 3000 thermocycing, the color difference $({\Delta}E^*)$ of experimental resin cements was within clinically acceptable ranges. Color stability of 4 different resin cements was comparatively excellent.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.1
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• pp.1-15
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• 1997

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.3
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• pp.360-370
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• 2012

This study investigates the interaction effects of mechanical property-based clusters and colorimetric tones on the subjective touch and color sensation of fabrics when sight and touch were simultaneously provided to humans. Each of six different silk fabrics was colored by digital textile printing to have three tones (pale, vivid, and grayish) and its mechanical properties were measured by a Kawabata Evaluation System (KES). Touch and color sensation were identified to be primarily influenced by mechanical property-based clusters and tones, respectively. In touch, 'smooth', 'warm', 'heavy', and 'soft' were found to be affected by interactive effects of mechanical property-based clusters and colorimetric tone so that the pale tone tended to make differences smaller among the clusters for the touch sensation, while the grayish tone seemed to contribute to larger differences of 'heavy'. However, an interaction effect was not found in the color sensation with touch even though the color sensation was also influenced by mechanical property-based clusters.

• Journal of the Korean Society of Costume
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• v.60 no.6
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• pp.101-116
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• 2010

The purpose of this thesis is in investigating the Korean twenties face color, according to the seasons, thus presenting a sample Korean Facial Color Map. The face is divided into 20 parts to take measures, and investigated through the four seasons. Minolta Chrome Meter CR-200 has been used for taking measures of the face color. Measuring subjects and area are, University students of both sex, living in the Suncheon. They are of ages the twenties. Classified measuring values of the skin colors are expressed following to the A. H. Munsell's color system. The result of this study is as followed. When comparing parts among male and female(make-up and no make-up) groups for changes with seasonal hue and value of a face color, differences have been sighted among these three groups following the seasons ; Spring(March), Summer(June), Autumn (September) and Winter(December). According to the result of Duncan's proof, the differences of the women group with the make-up attitude was shown only in value from Summer and Autumn, but no differences have been sighted between the make-up group and the no make-up group, concerning hue. Concerning hue, it was shown that men had a redder hue than women in all seasons. In Spring, both men and women had the strongest red hue, then from Summer to Autumn a strong yellowish hue appeared, to make place to a diverse coloring in Winter, followed by a reddish hue, to start all over again. Value number proved to be lower in the Summer and Autumn for the no make-up group when compared to the make-up group, showing an averaging high number for all seasons when putting on make-up; and men value number shows the lowest of the three groups.

• Journal of the Korean Home Economics Association
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• v.33 no.2
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• pp.168-180
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• 1995

The purpose of present study was to examine how each clothes colors on the basis of 5YR 7/3 face color affect clothes colors images as follows : (1) what general consciousness of clothes colors in, (2) how the impression of the harmony of 5YR 7/3 face color and clothes colors is, (3) when we divide clothes colors according to the property of colors- chromatic color and achromatic color, cool color.neutral color.warm color, in tone, in color colume- if there is the difference of visual evaluation, (4) image analysis of 45 clothes colors with the view of each kind of adjectives. The result of this study is as the following: 1. As a result of the analysis of general consciousness on clothes colors, when subjects chose clothes, they most considered colors and they also considered their face colors. They would choose the color of clothes, which were becoming to their having clothes colors or their face colors when they bought clothes. 2. The impressions of coordination of 5YR 7/3 face color and clothes colors consisted of three dimensions - evaluation, activity and harmony. 3. It was known that as a result of the analysis of visual evalutional differences according to dividing the clothes colors by property of colors, there were such notable differences that they might effect the coordination images of face color and clothes colors differently. 4. After arranging 45 clothes colors on the graphs in 17 adjectives, gethering them thogether in each dimension and as the result of the analysis in the evaluation dimension, estimation of yellow, light green column were low and that of achromatic colors were high. That is, it was known that the evalution dimension was concerned with hue of the color properties. In activity dimension, there were different image according to each adjectives. That is, it was known that the evalution dimension was concerned with hue of the color properties. In activity dimension, there were different image according to each adjectives. That is, it was known that the activity demension was concerned with value and chroma of the color properties. In harmony dimension, achromatic columm was high and yellow, green yellow, vivid green columm were low in harmony. That is, it was known that the harmony demension was concerned with hue of the color properties.

• Restorative Dentistry and Endodontics
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• v.49 no.1
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• pp.7.1-7.11
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• 2024

Objectives: This study aimed to evaluate the impact of substrate color and interface distance on the color adjustment of 2 single-shade composites, Vittra APS Unique and Charisma Diamond One. Materials and Methods: Dual disc-shaped specimens were created using Vittra APS Unique or Charisma Diamond One as the center composite, surrounded by shaded composites (A1 or A3). Color measurements were taken with a spectrophotometer against a gray background, recording the color coordinates in the CIELAB color space. Illumination with a light-correcting device and image acquisition using a polarizing filter-equipped cell phone were performed on specimens over the same background. Image processing software was used to measure the color coordinates in the center and periphery of the inner composite and in the outer composite. The color data were then converted to CIELAB coordinates and adjusted using data from the spectrophotometer. Color differences (ΔE₀₀) between the center/periphery of single-shade and outer composites were calculated, along with color changes in single-shade composites caused by different outer composites. Color differences for the inner composites surrounded by A1 and A3 were also calculated. Data were analyzed using repeated-measures analysis of variance (α = 0.05). Results: The results showed that color discrepancies were lowest near the interface and when the outer composite was whiter (A1). Additionally, Charisma Diamond One exhibited better color adjustment ability than Vittra APS Unique. Conclusions: Color discrepancies between the investigated single-shade composites diminished towards the interface with the surrounding composite, particularly when the latter exhibited a lighter shade.

• Clinical Endoscopy
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• v.56 no.5
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• pp.546-552
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• 2023

Techniques for upper gastrointestinal endoscopy are advancing to facilitate lesion detection and improve prognosis. However, most early tumors in the upper gastrointestinal tract exhibit subtle color changes or morphological features that are difficult to detect using white light imaging. Linked color imaging (LCI) has been developed to overcome these shortcomings; it expands or reduces color information to clarify color differences, thereby facilitating the detection and observation of lesions. This article summarizes the characteristics of LCI and advances in LCI-related research in the upper gastrointestinal tract field.

• Textile Coloration and Finishing
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• v.11 no.6
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• pp.43-50
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• 1999

Lichen had been used as dyestuffs before the discovery of synthetic dyes in Europe and by American Indians. To investigate the dyeability of Korean native lichens, 10 kinds of lichen were collected and colorants were extracted from them by boiling in water and fermenting in ammonia water. Silk fabrics were dyed with lichen extract, then the colour differences of dyed silk fabrics were measured before and after color fastness test. The most part of the lichen extracts(Fc, Hh, Me, Pl, Xm, Pr, Cj, Ld, Ry) dyed silk yellowish or reddish brown. The range of colors were 2.4Y 6.5∼10YR 6/7. Pa extract dyed silk purple(1.25RP 5/6). Color differences of laundered specimen with the silk before laundering were very small, but color of the dyed silks after exposing to light showed big differences with the specimen before exposing to light. The colors of the silks dyed with lichens changed from yellowish or reddish brown to greenish brown by laundering and by exposing to light. But the specimen dyed Pa extract changed from purple to blueish purple by laundering and reddish purple by exposing to light.