Color Difference Meter Research Articles

Aging mechanism and surface properties of Silica fluoropolymer coating and its application

The hydrothermal aging cycles experiment was carried out on synthetic Silica fluoropolymer coating (SiO2-FP). The hydrothermal aging mechanism, surface properties and protective efficacy on sandstones was studied. For comparison, the same study was conducted for commercial protective material acrylic resin Paraloid B72 (PB72). The hydrothermal aging mechanism was studied by Fourier infrared spectroscopy attenuated total reflection technique (ATR-FTIR) and x-ray photoelectron spectroscopy (XPS) technology. The surface properties were characterized by field emission scanning electron microscope (SEM), the CR-400 color difference meter, static contact angle and GMT6503 Electronic universal Tensile machine. The capillary water absorption, water absorption by complete immersion (CI) and water vapor permeability were measured to evaluate the protective efficacy on sandstones after treatment. The results of ATR-FTIR and XPS indicated that part of the ester groups in PB72 was hydrolysed and the chemical structure of SiO2-FP was not changed but only microphase separation occurred after 360 h of aging. After 360 h of aging, the PB72 film had obvious change and the SiO2-FP film only shown a minor change; the color change of PB72 film was very obvious and the color change of SiO2-FP film was within the acceptable range; the PB72 film changed from hydrophobic to hydrophilic and the SiO2-FP film still retained high hydrophobicity (119.3°); the SiO2-FP had a higher adhesive strength than PB72 at the end of aging. Compared with PB72, the SiO2-FP can obviously reduce the capillary water absorption and had a higher protective efficiency (97.25%), much lower soakage capacity (0.60%), higher water vapor permeability (267.0 ± 2) and less influence on the water vapor permeability. All the results demonstrated that the SiO2-FP has much better anti-aging ability and longer durability under hydrothermal condition. The SiO2-FP can provide adequate protection for sandstones. The SiO2-FP can be used as a suitable protective coating on sandstones.

Development of a multi-functional acrylic urethane coating with high hardness and low surface energy

This study developed multi-functional acrylic urethane coating materials with anti-graffiti, anti-contamination, and anti-adhesion properties. The newly-developed coating was synthesized by high glass transition temperature (Tg) acrylic polyol and low-viscosity single-end-type silicone oil. The coating materials were chemically bonded and reacted with isocyanate to form acrylic urethane. The hardness, surface energy, color difference value, and anti-adhesion properties were examined using nanoindentation, a contact angle analyzer, a color difference meter, and a universal tensile test machine, respectively. In addition, the degradation of the coating was evaluated using an accelerated weathering test, taking into account various degradation factors (UV, humidity, high temperature, and water). In general, the properties of the coating degraded due to the loss of silicone oil after the accelerated weathering test. However, the degradation was retarded when high Tg acrylic polyol and low-viscosity single-end-type silicone oil were chemically bonded. The newly-developed multi-functional acrylic urethane coating exhibited long-term stability against an accelerated weathering test of 120 h. The developed coating will be useful in broad applications, including harsh environments such as underground walls, heritage, facilities, and subways.

Comparative Study of Bacterial Cellulose Film Dried Using Microwave and Air Convection Heating

An investigation was conducted to analyze and compare the properties of bacterial cellulose (BC) films dried using microwave and air convection heating. Prior to the drying process, 90% of the water content inside the BC pellicles was removed through vacuum filtration. After that, the required drying time was only 3-5 min using microwave heating, 95% shorter than that observed for air convection heating. The properties of the BC sheets were characterized by Fourier transform infrared (FTIR), X-ray diffractometer (XRD), color difference meter, and tensile tester machine. The results showed that the structure of the BC films was the same for the BC films dried by microwave and air convection heating, i.e. cellulose I, as observed from FTIR spectra and XRD diagrams. Moreover, their color (L*, a*, and b* values) and mechanical properties were also almost identical. However, a slightly lower crystallinity and a higher swelling degree were observed for the BC film dried using microwave heating. These results suggest that microwave heating could be an alternative method of drying BC pellicles in order to shorten the processing time and reduce energy consumption when compared to air convection heating.

Whitening effect of l-ascorbate-2-phosphate trisodium salt on solar lentigos

Little is known about the anti-pigmenting effects of whitening agents on solar lentigos (SLs), which comprise ~ 60% of hyperpigmented facial lesions of Asian subjects. Lotions with or without 6% L-ascorbate-2-phosphate trisodium salt (APS) [test lotion (TL) and placebo lotion (PL), respectively] were applied twice daily for 24 weeks in a double-blind half-face study of 27 Japanese females with SLs on both sides of their faces. Pigmentation scores were evaluated using a photo-scale and the skin colors were assessed using a color difference meter and a mexameter for SLs and the non-lesional surrounding skin (NLS). Although the pigmentation scores were not significantly different between the TL and PL-treated SLs after 24 weeks, the L values of TL-treated SLs and NLS increased significantly with a significantly higher △L value in SLs than in NLS. In contrast, the L values of PL-treated SLs and NLS remained unchanged after the treatment. The number of subjects with > 2.0 △L was 7 of 27 (TL) and 0 of 27 (PL) in SLs and 3 of 27 (TL) and 0 of 27 (PS) in NLS. In contrast, the melanin index in TL-treated SLs and NLS significantly decreased with a significantly higher △melanin index in SLs than in NLS. Similarly, the melanin index of PL-treated SLs and NLS were significantly decreased with a significantly higher △melanin index in SLs than in NLS. These findings strongly indicate that APS has a weak but significant anti-pigmenting effect on SLs and a significant whitening effect even on normally pigmented healthy skin.

New Golden Red Sodium Calcium Silicate Glasses

Traditional golden red glasses were based on K2O-PbO-SiO2 composition system. In this paper, we reported new golden red glasses based on Na2O-CaO-SiO2 system without SnO2 and PbO in them. By using a spectrophotometer and chromamter color difference meter, it was found that the new glasses had similar optical properties to the traditional ones. The diameter of the gold particles in new glasses is around 40 nm determined by scanning electron microscope. The surface plasmon resonance created by the absorption of visible light emits golden red color. The benefits of using new golden red sodium calcium silicate glasses are the reductions of gold amount, cost and lead pollution to the environment.

출토복식 유물의 재현 현황 및 제안 : 어린이 도포와 장의 재현을 중심으로

Since excavated costumes has been in the ground for a long time, most of colors is discolored into lemon yellow and excavated. The original fabric and color of excavated costumes is reappeared via historical research, but is weighted in silk fabric and no vegetable one. Therefore, it is to dye textile weaving naturally and to reappeared with needlework based on children Dopo and relic of Jang-ui, which made by cotton and mixture, in this study, and the result is as follows; First, as for present condition for reappearance of excavated costumes so far, we have weaved it by homespun based on relic from similar fabric and color, and made colors by historical research. Second, we have measured the density and color of fabric via microscope and color-difference meter regarding analysis on Dopo and Jang-ui relic, and suggested basic data by analyzing size and shape. The shell was cotton[綿] in blue, and lining was same material in white but rough. In part is using blended Tabbye textile(交織). The features of Dopo is fixing Mu to back with a band. Jang-ui had square end collar, narrow straight sleeve from underarm to end, and side panel protruded outward. Collar was made of silk tabby. Third, we have weaved cotton[綿] and blended Tabbye textil(交織) by homespun, similar with relic for fabric, during reappearance process, and reappeared the shape of dyeing by hand sewing, which similar with measured size. Dyeing was natural dyeing using indigo and sappan wood. It is meaningful that it has arranged basic data for study on reappearance of excavated vegetable fabric relic in the result of this study. Also, it has proposed the method to reappear via scientific analysis and thorough historical research in reappearing the excavated costumes of vegetable textile, and hoped that it will be utilized for further research.

The difference of sensory qualities of apple fruit among eight cultivated varieties

The differences of sensory qualities among 8 apple varieties were studied by the properties, including moisture content, color difference and texture using color difference meter and texture analyser. These three parameters had a significant effect on the sensory edible qualities of apple. The results showed that, there were great differences on fruit sensory qualities among 8 cultivated apple varieties. Water content of Ralls was the highest; the moisture contents of Orin and Indo were lower. Golden Delicious in color difference was clearly distinguished from other varieties. The hue angles of Golden Delicious, Orin and Indo all showed negative values, while other varieties showed positive values. The chromas of Golden Delicious and Indo were higher than others. In terms of texture, for Ralls, Wangshanhong, Orin and Indo, both fruit flesh hardness and peel hardness were higher, while the two indexes of Gloden Delicious were lower.

열처리 방법에 따른 가공 인삼 열수추출물의 이화학적 품질 특성

The present study was carried out to investigate the physicochemical properties of hot water extracts of red ginseng powder prepared by two-stage hot air drying method using steamed ginseng and steaming liquid for 2.5 h under high-temperature and high-pressure autoclave condition. The total polyphenols, total flavonoids, total sugar, acid polysaccharides and crude saponin in hot water extracts from red ginseng powder were analyzed and determined, and the flavor components of ginseng were measured using color difference meter and an electronic tongue. The total polyphenol, total flavonoid, total polysaccharide, and acid polysaccharide of the red ginseng hot water extract obtained by autoclaving (ARG) were 9.06 mg GAE/g, 3.38 mg NE/g, 35.22 g/100 g, and 10.90 g/100 g, respectively. The final contents of the total polyphenols, total flavonoids, crude saponin were higher than those determined using other red ginseng methods; the time required for steamed red ginseng production reduced. The total ginsenoside content of ginseng including Rb1 was 10.69 mg/g, which is the lowest ARG. The processing conditions affected the conversion to ginsenosides unique to red ginseng. Red ginseng and steaming liquid obtained from the autoclave are expected to be in need for non-food materials and products as well as foods by improving the flavor components through conversion of red ginseng components into low molecular weight.

In vitro study of white spot lesion: Maxilla and mandibular teeth.

AimThe aim of the study was to evaluate the effect of resin infiltration on colour changes and surface roughness of artificial white spot lesions (WSLs) on maxillary and mandibular premolar.Materials and methodsSixty (60) extracted sound Maxilla (Mx) and Mandibular (Mn) premolars were randomly divided into 2 groups (test and control). Artificial WSLs were produced on buccal surface of teeth and were immersed in artificial saliva for 8 weeks. Colour components (L∗, a∗, b∗) and surface roughness (Sa∗) were assessed on 40 teeth using colour difference meter RD-100 and Alicona® Infinite Focus profilometer respectively. The measurements were done at baseline (T1), directly after artificial WSLs (T2), after 24 hours immersed in saliva and application of resin (T3) and immersion in artificial saliva for 1 (T4), 2 (T5), 4 (T6), 6 (T7) and 8 (T8) weeks. SEM images analysis were carried out on 20 teeth in four time points.ResultsThe values of L∗ (lightness), b∗ (yellow/blue) and Sa∗ (surface roughness) are gradually reduced to the baseline value. Whereas, the value of a∗ gradually increased with distinct treatment time to achieve the baseline value. The higher value of L∗ and Sa∗, the whiter the lesion suggesting higher degree of enamel demineralization and surface roughness. Lower L∗ values suggest a masking colour effect.ConclusionThe material produced favorable esthetics on colour and the surface roughness of teeth at distinct treatment times. It is recommended to be used to improve WSL post orthodontic treatment.

The effect of molecular weight on light scattering of photonic poly styrene-block-poly-2-vinyl pyridine nano-structure

ABSTRACTOne dimensional structures often limit viewing angle as well as reflection color changes [1]. We report a simple strategy to fabricate the ellipsoidal block copolymer nanoparticles [2], which have a wider viewing angle. The photonic crystals were made with the polystyrene-block-poly-2-vinyl pyridine (PS-b-P2VP) dispersed in chloroform. When the PS-b-P2VP was sonicated in polyvinyl alcohol (PVA), it became white emulsion. The photonic crystals were formed by self-assembly of block copolymers. We observed particle structure variations(color of viewing angle) according to the difference in molecular weight, which were 57k–57k, 75k–66.5k. The swelling and nature of light scattering from structured particles changed by the addition of ethanol. The color was measured by color-difference meter [3–5]. The particles with low molecular weight showed the short wavelength reflection [6–9].

Construction and adhesion performance of biomass tetrahydro-geraniol-based sustainable/transparent pressure sensitive adhesives

Abstract Using the tetrahydro-geraniol acrylate (TGA) synthesized from biomass tetrahydro-geraniol, UV-cured transparent acrylic pressure sensitive adhesives (PSAs) composed of semi-interpenetrating networks were successfully fabricated. The utility for optically clear adhesive on adhesion performances according to various concentrations of TGA in the acrylic PSAs were investigated. After characterizing the photo-polymerized PSA syrups, the optical properties for the acrylic PSA films were examined using UV–vis spectroscopy, a color-difference meter, and a haze meter. The acrylic PSAs exhibited high transparency and stable weather-ability under reliability testing (85/85 test). With increasing TGA concentration in the acrylic PSAs, adhesion properties such as the 180° peel strength, shear holding power, and probe tack had decreased.

Preparation of biomass-based transparent pressure sensitive adhesives for optically clear adhesive and their adhesion performance

UV-cured transparent acrylic pressure sensitive adhesives (PSAs) composed of semi-interpenetrating networks were prepared using the menthyl acrylate (MnA) and tetrahydro-geraniol acrylate (TGA) synthesized from menthol and tetrahydro geraniol, respectively. This study investigated the adhesion performance and environmental reliability of the resulting acrylic PSAs by changing the mole ratio for MnA and TGA while fixing the mole ratio for 2-hydroxyehtyl acrylate (2-HEA) in the PSAs. Also, the optical properties of the acrylic PSAs for optically clear adhesive applications were examined by UV–Vis spectroscopy, color-difference meter, and haze meter. All acrylic PSAs exhibited high transparency (>92%) and stable weatherability under reliability testing (85/85 test), regardless of the various comonomer compositions. The resulting acrylic PSAs showed proper adhesion performance to be allowed to use as optically clear adhesive; 180° peel strength of 1.6–4.0 kgf/25mm, probe tack of 0.25–0.43 kgf, and shear holding power of 0.10–0.17mm.

Evaluation of relationship between state of wheat flour-water system and mechanical energy during mixing by color monitoring and low-field 1H NMR technique

The relationship between the mixing state of wheat flour–water systems and the mechanical energy generated using a vertical mixer was revealed. To determine the mixing state, we measured the color changes in the systems using a color difference meter by adding caramel color regent as the indicator and measured the spin-spin relaxation time (T2) by a low-field 1H NMR technique. The mixing progress was calculated and presented in terms of an “action number”. As mixing progressed, the net energy increased and the net power also increased gradually, but after reaching its maximum value of 0.8 kJ, it decreased. At the boundary of this inflection point, the state of the wheat flour–water mixture greatly changed. The relationship between the net energy and the color of the mixture, a turning point appeared at the net energy of 0.8 kJ, and this behavior was consistent with the NMR T2 relaxation data.

Synthesis Characterization and Photocatalytic Activity of SnTiO3 Prepared by Co-Precipitation Peroxide Method

The application of titanium dioxide in the field of photocatalyst was limited. Since, it was activated only a small extend under UV irradiation. While the metal doped TiO2 had shown better photocatalytic activity. The work designed to prepare tin titanate (SnTiO3) by a simple co-precipitation peroxide method. The ratio of the starting compounds, Sn and Ti was taken as 1:1. The prepared powder was calcined at 850°C. The stoichiometric ratio of the synthesized titanate was measured by using AAS. The synthesized titanate had analyzed by X- ray diffraction (XRD). FTIR was taken for confirming the bonding characteristics of Sn-O and O-Ti-O. Thermo gravimetric analysis (TGA) was used to analyze the decomposition temperature. The optical and photocatalytic activity of the synthesized powder was evaluated by Lead carbonate test by using Hunter lab color difference meter. Color difference was determined using a white medium and strength had been determined using black medium. The prepared SnTiO3 powder had exhibited better photocatalytic activity.

Contrast Investigation on Relative Translucency of Four Ultra-Transparent Dental Zirconia Materials after Veneered

The purpose of this article is to contrast the relative translucency of four ultra-transparent dental zirconia materials after veneered, including Cercon zirconia, Zenostar zirconia, Lava zirconia and Upcera zirconia. All zirconia ceramics were prepared into samples of diameter 10mm and thickness 0.5±0.01mm.The relative translucency of samples were measured with color difference meter and statistically analyzed with SPSS 17.0.This experiment confirms that the existence of statistically significant differences in the relative translucency between different zirconia ceramics. According to the numerical level, the relative translucency of zirconia materials from high to low is Zenostar ZR Translucent>Lava Plus High Translucency zirconia> Cerconht full contour zirconia > Upcera zirconia. Zenostar ZR Translucent and Lava Plus High Translucency zirconia can be used to restore adjacent teeth that are higher translucent, while Cercon ht full contour zirconia and Upcera zirconia is better for molar teeth with poor relative translucency.

Effect of gamma irradiation on Korean traditional multicolored paintwork

Abstract Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe 2 O 3 ), Jangdan (Minium; Pb 3 O 4 ), Whangyun (Crocoite; PbCrO 4 ), and Jidang (Rutile; TiO 2 ), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d’Eclairage (CIE) color values ( L *, a *, b *) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE * unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong.

The dual-wavelength excitation photochromic behavior of organic induced MoO3 powders synthesized via a hydrothermal route

Production of molybdenum oxide materials with dual-wavelength excitation photochromism which could be motivated by UV and visual light is attractive. Here, we have successfully synthesized the novel dual-wavelength excitation photochromic molybdenum oxide (MoO3) powders with organic inducers. The variety and amount of organic inducers have great impact on the final product morphologies. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET nitrogen physisorption apparatus, ultraviolet–visible diffuse reflectance spectroscopy (UV–vis), and color difference meter. The XRD spectrums of samples demonstrate that the as-obtained products are pure hexagonal phase. The non-induced MoO3 powders present to be neat hexagonal prisms while the induced MoO3 powders possess flower-like and yuba-like structures. In addition, we found that sample S3 got the optimized photochromic property. This could be attributed to the enhanced light harvesting from multiple light reflections and scattering in-between the cavities on the surface of spheroidal-flower structure.

Hydrothermal synthesis and studies on photochromic properties of Al doped WO3 powder

A series of pure and aluminum (Al) doped WO3 powders were synthesized at low temperature. The as synthesized materials have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible (UV–VIS) spectroscopy and color difference meter, respectively. A relation was found between the color difference and the UV–VIS photochromic activity. Moreover, the optical band gap of the as-prepared powder narrowed due to the appearance of impurity levels as the Al3+ ions migrated into the WO3 crystal lattice. Some rod-like particles have been found to decrease with the increase of Al concentration. An optimum Al concentration was found to be 0.25% to present the best UV-light induced photochromic activity. The mechanism of photochromic process of the Al-doped WO3 powders has been discussed in detail based on the characterization results.

Morphology, Mechanical and Thermal Properties of the Blends of Poly(Trimethylene Terephthalate)/Acrylonitrile-Styrene-Acrylic Copolymer

Poly (trimethylene terephthalate)/acrylonitrile-styrene-acrylic copolymer blends were prepared and their morphology, thermal aging and mechanical properties were investigated by using the polarized optical microscopy, universal material testing machine and color-difference meter, repectively. The results suggest that ASA and PTT are partially miscible in the blends, and when TPEE content is 50%, a bi-continuous phases form in the blend. The PTT’s spherulites in the blends become smaller and even microcrystallites with increasing ASA content. ASA component has good effect on toughen PTT by increasing blends’ impact strength but depresses the tensile strength of the blends. ASA has no influence on the thermal aging properties of PTT, and PTT/ASA blend has better thermal aging resistance than that of PTT/ABS blend.

Novel coral-like hexagonal MoO3 thin films: Synthesis and photochromic properties

MoO3 thin films were obtained by varying the precursor concentration (Cp) using a hydrothermal method. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), ultraviolet–visible diffuse reflectance spectroscopy and a color difference meter were employed for the characterization of synthesized thin films. With the increase of precursor concentration, the morphology of MoO3 thin films changed from hexagonal prismatic structures to coral-like structures and finally straw-like structures. XRD results showed that all samples can be indexed to the hexagonal structure of MoO3. Additionally, the band gap of all MoO3 thin films was around 3.16eV calculated from UV–vis diffuse reflectance spectrum. The as-prepared MoO3 film with coral-like structures possessed the maximum color difference value (ΔC=2.33). This result indicates that MoO3 film prepared with the precursor concentration of 0.18M exhibits excellent photochromic properties due to the large exposed surface provided by coral-like hierarchical structure.