In this study, ozone oxidation treatment was applied to improve the strength of continuous carbon fiber reinforced thermoplastic composites. This treatment was carried out using both carbon fiber fabric (CFF) and polypropylene (PP) sheet in the prepreg fabrication. (ozone concentration: 60mg/L, oxidation time: 6hours)
In comparison with the untreated ones, it was found that flexural strength was increased by 99%, and interlaminar shear strength was increased by 68%.
As the results of observing the surface of ozone oxidation treated CFF and PP sheet by XPS and FT-IR, it was confirmed that the oxygen-containing functional groups were generated on both sides. The reason for improvement in strength was considered to be because the adhesion at the interface between CFF and PP sheet by these functional groups was improved.
Furthermore, melt flow rate of PP sheet was increased to 2.4 times compared to untreated by ozone oxidation treatment and this caused an additional effect on the improvement in the strength of CFRTP.

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The exterior components are often painted with metallic color. However, painting increases the cost and environmental impact. So, manufacturing technology that makes metallic-colored plastic parts by injection molding without painting is being developed by many companies. But color unevenness hinders commercialization. In this study, we focused on the dispersion of metallic flakes that cause uneven color in metallic molding and investigated in order to evaluate the dispersion. We made test pieces with different sizes of metallic flakes by injection-molding and evaluated influence of proportion of metallic flakes on the qualities of plastic parts. We took the test pieces using a CCD microscope and compared the results of image analysis. We selected skewness (SKEW),angular second moment (ASM) and entropy (ENT) as values that indicate the features of the image. The following conclusions were obtained. (1) When the ratio of metallic flakes increased, flakes that are present at a position near surface increased. In the gray level histogram, SKEW decreased. The results of the analysis by co-occurrence matrix, ENT increased. (2) When the size of metallic flakes increased, SKEW increased. The results of the analysis by co-occurrence matrix, ASM increased. (3) It was considered that the difference of the ratio and the size of metallic flakes affected the results of image analysis. (4) It was suggested that gray level histogram and co-occurrence matrix were useful for evaluating the dispersion of metallic flakes.

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