scholarly journals Influence of UV Radiation on the Color Change of the Surface of Steamed Maple Wood with Saturated Water Steam

Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 217
Author(s):  
Ladislav Dzurenda ◽  
Michal Dudiak ◽  
Eva Výbohová
Keyword(s):  
Uv Radiation ◽  
Color Change ◽  
Color Space ◽  
Color Stability ◽  
Color Difference ◽  
Saturated Steam ◽  
Water Steam ◽  
Saturated Water ◽  
Red Color ◽  
Uv Lamp

The wood of maple (Acer Pseudopatanus L.) was steamed with a saturated steam-air mixture at a temperature of t = 95 °C or saturated steam at t = 115 °C and t = 135 °C, in order to give a pale pink-brown, pale brown, and brown-red color. Subsequently, samples of unsteamed and steamed maple wood were irradiated with a UV lamp in a Xenotest Q-SUN Xe-3-H after drying, in order to test the color stability of steamed maple wood. The color change of the wood surface was evaluated by means of measured values on the coordinates of the color space CIE L* a* b*. The results show that the surface of unsteamed maple wood changes color markedly under the influence of UV radiation than the surface of steamed maple wood. The greater the darkening and browning color of the maple wood by steaming, the smaller the changes in the values at the coordinates L*, a*, b* of the steamed maple wood caused by UV radiation. The positive effect of steaming on UV resistance is evidenced by the decrease in the overall color difference ∆E*. While the value of the total color diffusion of unsteamed maple wood induced by UV radiation is ∆E* = 18.5, for maple wood steamed with a saturated steam-air mixture at temperature t = 95 °C the ∆E* decreases to 12.6, for steamed maple wood with saturated water steam with temperature t = 115 °C the ∆E* decreases to 10.4, and for saturated water steam with temperature t = 135 °C the ∆E* decreases to 7.2. Differential ATR-FTIR spectra declare the effect of UV radiation on unsteamed and steamed maple wood and confirm the higher color stability of steamed maple wood.

scholarly journals Changes in the Physical and Chemical Properties of Alder Wood in the Process of Thermal Treatment with Saturated Water Steam

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 898
Author(s):  
Michal Dudiak ◽  
Ladislav Dzurenda
Keyword(s):  
Thermal Treatment ◽  
Chemical Properties ◽  
Alnus Glutinosa ◽  
Color Difference ◽  
Average Density ◽  
Saturated Steam ◽  
Water Steam ◽  
Color Changes ◽  
Saturated Water ◽  
Range Of Values

The paper presents changes in color and selected physico-chemical properties of alder (Alnus glutinosa) wood during the process of thermal treatment of the wood with a saturated steam-air mixture or saturated water steam in the temperature range t = 95–125 °C for τ = 3 to 12 h. During the process of thermal treatment of alder wood, the original light white-gray color changes depending on the temperature and time of modification to soft reddish-brown to dark brown color shades. Color changes of alder wood expressed in the form of the total color difference are in the range of values ∆E* = 2.7–31.7. Measurements of the density of thermally treated alder wood in the dry state indicate that due to the thermal treatment of alder wood, the density decreases by ρ ≤ 4.6% compared to the average density of native alder wood. Due to the hydrolysis of hemicelluloses, in the process of thermal treatment of wet alder wood, its acidity changes in the range of values: pH = 4.9 to 3.1. Analyzes of ATR-FTIR spectroscopy indicate changes in alder wood extractants and hemicellulose degradation. A decrease in unconjugated and an increase in conjugated carbonyls was observed at all temperatures of thermal modification of alder wood. Measurements indicate changes in the lignin of alder wood and the fact that as the temperature increases, the formation of new carbonyls increases, which is reflected in the change of the chromophoric system.

Cr3+ Effect on the Correlation between Lightness Difference and Color Difference of Ruby Red

2010 ◽  
Vol 177 ◽  
pp. 624-627 ◽  
Author(s):  
Ying Guo ◽  
Xiang Li ◽  
Li Tian
Keyword(s):  
Correlation Analysis ◽  
Partial Correlation ◽  
Color Index ◽  
Color Change ◽  
Color Space ◽  
Color Difference ◽  
Partial Correlation Analysis ◽  
Significance Level ◽  
Red Color ◽  
The Impact

The correlations between of lightness, chroma, Cr3+ and color index were studied to analyze the impact of all these three elements on ruby red color; and with the color difference research, the lightness difference is testified to be the key affecting color appearance. Based on the uniform color space CIE 1976L*a*b*, the ruby displays the best red color when the content of Cr3+ is within (1555, 5183ppm), L* (32.64, 44.25) and ho  (354.14, 0.7). With the help of partial correlation analysis of color difference, it is illustrated that the correlation between L* and E* (r=0.999) is relatively higher than that between L* and E* (r=0.948); and with high significance level ( = 0.129) of H* and E*, it shows that H* has little impact on E*. It is concluded that the color change of ruby from red to purple are mostly affected by lightness change; lightness difference should be considered as the most important factor when evaluating the red color of ruby, and then followed by the chroma and hue jointly.

scholarly journals Evaluation of the process thermal treatment of maple wood saturated water steam in terms of change of pH and color of wood

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 2550-2559
Author(s):  
Ladislav Dzurenda ◽  
Anton Geffert ◽  
Jarmila Geffertová ◽  
Michal Dudiak
Keyword(s):  
Thermal Treatment ◽  
Color Change ◽  
Ph Value ◽  
Statistical Processing ◽  
Color Difference ◽  
Acer Pseudoplatanus ◽  
Water Steam ◽  
Saturated Water ◽  
Before And After ◽  
Total Color Difference

Changes in maple wood’s pH and color (Acer pseudoplatanus) were evaluated before and after thermal treatment process with saturated water steam. Maple wood was thermally treated at temperatures: tI = 105 ± 2.5 °C, tII = 125 ± 2.5 °C, and tIII = 135 ± 2.5 °C for τ ≤ 12 hours. Direct pH measurement of maple wood with a moisture content above the fiber saturation point (FSP) was performed using a pH-meter SI 600 with a Lance FET + H puncture probe. The polynomial dependence of pH and total color difference ∆E* on temperature t time τ was calculated by statistical processing of measured results. The correlation between the total color difference ∆E* of maple wood in the process of thermal color modification and the pH value is expressed y the equation: ∆E* = 4.5516∙(pH)2 – 48.405∙(pH) + 134.35. This dependence is a suitable tool for assessing the achieved color change based on the change of wood pH in the technological process.

scholarly journals Effects of Acidic Beverages on Color Stability of Bulk-Fill Composites with Different Viscosities

2021 ◽  
pp. 338-347
Author(s):  
Soner Şişmanoğlu ◽  
Görkem Sengez
Keyword(s):  
Orange Juice ◽  
Color Change ◽  
Color Space ◽  
In Vitro Study ◽  
Color Stability ◽  
Color Difference ◽  
Composite Resins ◽  
Distilled Water ◽  
Acidic Beverages

The aim of this in vitro study is to investigate the effects of acidic beverages on the discoloration of bulk-fill composites with different viscosities. 144 disc-shaped specimens (8mm diameter × 2mm thick) were prepared from four different composite resins including a nanohybrid (Filtek Ultimate), two packable bulk-fill (Filtek Bulk Fill, Tetric N Ceram Bulk Fill), and a flowable bulk-fill composite (Tetric N Flow Bulk Fill). The specimens of each group were divided into 3 subgroups and submerged in distilled water, orange juice and coke (n=12). Color difference (∆E) were measured using CIELab color space and a compact spectrophotometer (VITA Easyshade) at baseline and after 30 days of immersion. Data were analyzed using two-way ANOVA and Tukey's HSD post-hoc tests (P<0.05). Two-way ANOVA revealed that both material type and staining solution significantly influenced ∆E values (P<0.001). Immersion in orange juice resulted in greater and significant discoloration over time in comparison to distilled water and coke (P<0.05). Tetric N Ceram (∆E=7.0) and Tetric N Flow (∆E=7.7) bulk-fill restoratives showed highest color change values after 30 days of immersion in orange juice. This study suggests that a discoloration above the clinically acceptable threshold (∆E>2.7) was observed for all bulk-fill composites tested. It can be speculated that orange juice has a more negative effect on the color stability compared to coke. Additionally, flowable bulk-fill composite was more prone to discoloration than condensable bulk-fill composites.

scholarly journals The Role of Scale Adjustment in Color Change Evaluation

Instruments ◽  
2019 ◽  
Vol 3 (3) ◽  
pp. 42 ◽  
Author(s):  
Gueli ◽  
Pasquale ◽  
Politi ◽  
Stella
Keyword(s):  
Color Change ◽  
High Reliability ◽  
Research Work ◽  
Color Space ◽  
Color Difference ◽  
Color Measurement ◽  
Cielab Color Space ◽  
Archaeological Excavations ◽  
Cielab Color

The aim of this research work was to assess the influence of different scale adjustment conditions on both color measurement and color difference quantification and, in particular, to determine the best procedure to follow for a high-reliability protocol. This issue is very important in the Cultural Heritage field and, above all, in color measurement, which is carried out at different times during conservation and restoration campaigns or during archaeological excavations. Color change evaluation, performed by way of spectrophotometric measurements under different scale adjustment procedures on selected samples represented by colored reflectance standards and colored paintings, aimed to obtain results not only on ideal samples (certified standards) but also on real case studies (paintings). The study was conducted by focusing on the coordinates of the CIELAB color space and, in particular, on the calculation of the ΔE*ab quantity. The results show the introduction of nonsystematic variation with different scale adjustment procedures independent of materials and hue.

Fluorescent-Based Temperature Measurement with Simple Compensation of Photo-Degradation Using Hydrogel-Tool and Color Space Conversion

2013 ◽  
Vol 25 (4) ◽  
pp. 596-602 ◽  
Author(s):  
Hisataka Maruyama ◽  
◽  
Taisuke Masuda ◽  
Fumihito Arai
Keyword(s):  
Color Space ◽  
Color Difference ◽  
Temperature Measurements ◽  
Blue Color ◽  
Photo Degradation ◽  
Color Space Conversion ◽  
System A ◽  
Red Color ◽  
Brightness Fluctuation ◽  
Increasing Temperature

We developed a method to obtain stable and longlifetime temperature measurements using a fluorescence micromeasurement system. A hydrogel tool containing nano-semiconductor quantum dots (Q-dots) was developed as a fluorescent temperature indicator. We used image processing to convert RGB information to other color information to compensate for photodegradation. The temperature was calibrated using the hydrogel tool in several color spaces, includingRGB(R: red,G: green,B: blue),HSV(H: hue,S: saturation,V: value (brightness)), andYCrCb(Y: brightness,Cr: red color difference,Cb: blue color difference). The calibration results showed thatR,G,B,Y, andCrdecreased monotonically with increasing temperature, whereasHandCbdid not decrease monotonically. The photodegradation analysis showed thatCrwas robust against the brightness fluctuation; however,R,G, andBstrongly affected the brightness fluctuation because these values included the brightness information. These results show that temperature measurements based onCrvalues are suitable to compensate for photodegradation and have a sensitivity of -1.3%/K and an accuracy of 0.3 K. These values are the same as those obtained using the fluorescence intensity method.

scholarly journals Color Stability of the Bulk-Fill Composite Resins with Different Thickness in Response to Coffee/Water Immersion

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Sayna Shamszadeh ◽  
Seyedeh Mahsa Sheikh-Al-Eslamian ◽  
Elham Hasani ◽  
Ahmad Najafi Abrandabadi ◽  
Narges Panahandeh
Keyword(s):  
Composite Resin ◽  
Color Change ◽  
Imaging System ◽  
Water Immersion ◽  
Color Space ◽  
Color Stability ◽  
Composite Resins ◽  
Distilled Water ◽  
Color Changes ◽  
Post Hoc

We aimed to evaluate the color stability of bulk-fill and conventional composite resin with respect to thickness and storage media. Twenty specimens of a conventional composite resin (6 mm diameter and 2 mm thick) and 40 specimens of the bulk-fill Tetric EvoCeram composite resin at two different thicknesses (6 mm diameter and 2 mm thick or 4 mm thick,n=20) were prepared. The specimens were stored in distilled water during the study period (28 d). Half of the specimens were remained in distilled water and the other half were immersed in coffee solution 20 min/d and kept in distilled water between the cycles. Color changes (ΔE) were measured using the CIEL⁎a⁎b⁎color space and a digital imaging system at 1, 7, 14, and 28 days of storage. Data were analyzed using Two-way ANOVA and Tukey’s HSD post hoc test (P<0.05). Composite resins showed significant increase in color changes by time (bulk-fill > conventional;P<0.001). Coffee exhibited significantly more staining susceptibility than that of distilled water (P<0.001). There was greater color changes with increasing the increment thickness, which was significant at 14 (P<0.001) and 28 d (P<0.01). Color change of bulk-fill composite resin was greater than that of the conventional one after coffee staining and is also a function of increment thicknesses.

The Influences of Lightness Variation of the Non-Color Background on the Color of the Blood Amber

2014 ◽  
Vol 633 ◽  
pp. 524-535
Author(s):  
Ya Xiao ◽  
Ying Guo ◽  
Da Peng Chen
Keyword(s):  
Color Space ◽  
Measurement Instrument ◽  
Color Difference ◽  
High Brightness ◽  
Color Parameters ◽  
Color Saturation ◽  
Red Color ◽  
Hue Angle ◽  
Color Background ◽  
The One

In this study, based on CIE L*a*b* uniform color space, the Color i5 measurement instrument was used to measure the color parameters of seven blood amber samples under the D65 illuminant. In addition, the influences of lightness variation of the non-color background on the lightness, the color saturation and the hue of the blood amber were also investigated and discussed. The results show that the lightness of the blood amber is significantly enhanced with the increased lightness of the non-color background and the blood amber with higher transparency is more sensitive to the change of the non-color background; the color saturation of the blood amber increases gradually with the raise of the lightness of the non-color background, which means that the blood amber on the high-lightness background looks more bright-colored than the one on the low-lightness background; the red color hue angle range of blood amber turns out to be diffusing with the increase of the lightness of the non-color background, which means that a slight difference of the hue can be more easily discriminated on the high-brightness background. Thus, it can be concluded that the blood amber with higher transparency is much easier to be influenced by the non-color background; and the increase of the lightness of the non-color background can lead to higher lightness, more bright-colored saturation and diffused hue angle range of the blood amber; and the blood amber is more bright-colored and the color difference can be more easily discriminated on the background with higher lightness.

scholarly journals The Effects of Coffee and Energy Drink on Color Stability of Hybrid Ceramics

2021 ◽  
Author(s):  
Işıl Sarıkaya ◽  
Hande Dilli
Keyword(s):  
Color Change ◽  
Color Stability ◽  
Color Difference ◽  
Ceramic Materials ◽  
Energy Drink ◽  
Control Group ◽  
Distilled Water ◽  
Color Measurements ◽  
Difference Formula ◽  
Significant Difference

Purpose: The aim of this study was to compare the color stability of two different hybrid ceramic materials. Materials & Methods: Using the precision cutting device (Micracut, Metcon, Turkey), 36 specimens (12 x 15 x 1 mm) were obtained from Vita Enamic (Vita Zahnfabrik, Germany) and Lava Ultimate (3M ESPE, St.Paul, USA) CAD / CAM blocks. After finishing procedures were completed, all specimens were stored in distilled water for 24 h. Then, the specimens were dried and the initial color measurements were made. L, a, b values were determined using a spectrophotometer (Vita Easy Shade, Vita Zahnfabrik, Germany). The specimens were then divided into 3 test groups and stored in coffee (Nescafe Classic, Turkey) (G2, G5), energy drink (Red Bull, Austria) (G3, G6), and in the distilled water as the control group (G1, G4), for 48 h. After 48 h, the specimens were washed with distilled water and dried. Second color measurements were made. ∆E00 values were calculated using the CIEDE 2000 color-difference formula. Results: Data were analyzed by two-way ANOVA. Multiple comparisons were made with Bonferroni’s test. There was a statistically significant difference between 2 ceramics (p=0.035). Generally, Lava Ultimate showed more color change than Vita Enamic. Among the beverages, coffee was significantly different for both ceramics than control and energy drink (p<0.05). Conclusion: Lava Ultimate, showed more color change than Vita Enamic. Coffee has also been determined as the most colorant drink for both hybrid ceramics.

scholarly journals Spectrophotometric Evaluation of Color Changes of Bleach-shade Resin-based Composites after Staining and Bleaching

2014 ◽  
Vol 15 (5) ◽  
pp. 587-594 ◽  
Author(s):  
Rafat Ibrahim Farah ◽  
Hytham Elwi
Keyword(s):  
Color Change ◽  
Color Space ◽  
Color Stability ◽  
Light Activation ◽  
Carbamide Peroxide ◽  
Color Changes ◽  
Stain Removal ◽  
Storage Solutions ◽  
Color Differences ◽  
Level Of Significance

ABSTRACT Spectrophotometric evaluation of color changes of Bleachshade resin-based composites after staining and bleaching. Aim The aim of this study was to evaluate the color stability of two commercially available bleach-shade resin composites (RC) after exposure to 3 storage solutions and the effect of 3 bleaching agents on the color stability and stain removal from stained RC. Materials and methods Two bleach-shade RC were evaluated in this study, including a nanofilled RC, FiltekTM Z350 XT (FZ), and a nanohybrid RC, Tetric® N-Ceram (TC), in the extra-white body (shade) (XWB) and L shades, respectively. Twenty-seven disk-shaped specimens, each measuring 12 mm in diameter and 2 mm in thickness, were prepared for each RC, with a total of 54 specimens. Specimens were randomly allocated into 3 groups of 9 specimens each and immersed in 3 storage solutions (distilled water, tea and coffee) for 7 days period. The 9 specimens in each staining group were further divided into 3 subgroups. Specimens in each subgroup (n = 3) were bleached using one of the bleaching agents (10 and 16% Zoom NiteWhite amorphous calcium phosphate (ACP), and Zoom 2 chairside with light activation) for 5 days period. The specimen colors were measured with spectrophotometer. The measurements were performed on each sample three times at baseline, after staining, and after bleaching. Color was expressed using the commission international de I'Eclairage (CIE) L*a*b* color space. The color differences (ÄE) between the three measurements were calculated and the results were statistically analyzed using Two-way and Three-way analysis of variance (ANOVA) and Tukey's posthoc tests. Level of significance was set at p < 0.05. Results Tetric® N-ceram materials demonstrated significantly less color change than the FZ and the color change, which was greater after storage in coffee compared to tea, was statistically significant. The bleaching agents significantly influence the color changes of composite specimens. All groups showed (ÄE) values below 3.3 after bleaching, except for ‘Zoom 2 chairside’ with light activation groups, which is shown clinically unacceptable lighter shade (ÄE >3.3). Conclusion Bleach-shade composites showed significant discoloration (ÄE > 3.3) after being immersed into coffee and tea solutions. Nanofilled composites discolored more than nanohybrid composites, and carbamide peroxide-based bleaching agents were effective in reducing the discoloration to a clinically acceptable value (ÄE > 3.3). How to cite this article Farah RI, Elwi H. Spectrophotometric Evaluation of Color Changes of Bleach-shade Resin-based Composites after Staining and Bleaching. J Contemp Dent Pract 2014;15(5):587-594.

Sign in / Sign up

Export Citation Format

Share Document