Papers by Keyword: Color Difference

Abstract: This paper discusses the effects of different retention agent such as: CPAM, APAM, PAE+CPAM, cationic starch with high degree of substitution and modified starch on the reversible thermochromism materials in anti-counterfeiting paper retention rate, and then determined the optimum dosage of retention agent in the slurry. According to the anti-counterfeit paper color value, the mechanism of reversible thermochromism paper was studied. The experimental results show that when the slurry with retention agent, the reversible thermochromism materials in the anti-counterfeit paper retention increased significantly. This suggests that retention agent in pulp fiber has played the role of bridge and link, thus ensuring the security of reversible thermochromism paper.

Abstract: 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.

Abstract: Digital camera which has the advantage of real-time image transferring and easily processing is more and more widely used in the packaging and printing industry with the rapid development of high-tech electronics industry. However, the color in digital camera is not accurate which affect the application. To minimize the color difference between the color in the digital camera and the real color, the color reproduction methods is developing. The field comparative experiment is carried out to compare the performance of color reproduction methods, such as polynomial regression algorithm in different color space, and color checker passport. The results show that fourth order polynomial regression color reproduction in XYZ color space has the best performance.

Abstract: Digital camera is widely used in the data collection of objective and background in the field of pattern design and supervisory controlling. However, the color in digital photo copied from camera is not in accord with the actual color of objective, which affects the accuracy of design pattern. The polynomial regression algorithm is widely used in color reproduction of image input and output area. The accuracy of color reproduction is related to the different order. Therefore, the field experiment is developed. The application indicates that the performance of four order polynomial regression color reproduction is the best algorithms and it can be used in color reproduction.

Abstract: Three different plastic packaging (CPP, LDPE and HDPE) were researched on preservation of carp in this study, and the indicatiors of color difference and sensory evaluation were tracked. Color difference of carp block muscle was analyzed by CR-400 chroma meter, and the value of L*, a* and b* were measured at different stage of storage. At the same time, sensory evaluation was conducted. The results showed that the value of L* a* and b* all increased along with storage days, which indicated that the color of the carp block skin turning lighter, redder and yellower. The material of High Density Polyethylene (HDPE) could be better for keeping muscle color of carp during storage. However, the results of sensory evaluation showed that Cast Polypropylene (CPP) was better for keeping shelf quality of carp block. There was negative correlation between color difference and sensory evaluation. The value of b* could better represent sensory score in MAP, for it was correlate significantly with sensory evaluation in all three types of packaging.

Abstract: The freshness of red sea bream stored under 0°C was analyzed by physical methods, the indicators including the texture, color difference and water holding capacity. The hardness, springiness and cohesiveness showed fluctuant decrease during the storage of 21 days. All of them correlated negatively with the storage time (r=-0.61, -0.60 and-0.68, respectively). While the gumminess and chewiness did not show evident correlations with time. The values of resilience were decreased significantly with storage time (r=-0.81). The L* values kept increasing within the first 12 days of storage, and then decreased until the end of storage. The a* values decreased with the over time, while the increase of b* values were observed. The water holding capacity decreased within 9 days and then increased in the following 6 days. However, 15 days later, it decreased again. The results showed that the resilience, b* values and water holding capacity significantly correlated with the storage time.

Abstract: PE/thermochromic composite membrane is a kind of new functional materials which is composited by PE and thermochromic membrane.PE/thermochromic composite films retain the thermochromic membrane performance of changing the color by absorbing the heat. The composite film cannot be dissolved by water because of the structure which PE film is attached to the both sides of thermochromic film.The effect of the composite film and Nylon/low density polyethylene (LDPE) film on quality of fresh pork meat stored were investigated respectively. The treated meat samples were analyzed periodically for color difference. The results indicate that preservation effect of both films has no significant difference when the fresh pork are stored at 3-5°C, but PE/thermochromic composite films has better preservation effect at 30°C in compared to the Nylon/ LDPE. filmsfilms