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本研究係利用電子掃描顯微／Ｘ射線能譜分析法 (SEM/EDX)，分析探討不同
廠牌汽車油漆樣品，以促進耐候性試驗所模擬的天候狀況，對油漆成份所造成之影響。
結果顯示以無機顏料為主的汽車油漆片，較適用於進行元素含量的差異檢定分析，而且
此類以無機顏料為主的汽車油漆片，其元素含量在經過不同促進耐候性試驗時間後，並
無顯著性差異存在，初步顯示頗適合作為自動化查詢之應用。在光澤度的變化方面，對
於結構上具有金油層的汽車油漆片而言，則隨著促進耐候試驗時間的增加，有逐漸下降
的趨勢。在色差值變化方面，也因汽車油漆片的不同，而有不同的變化。另外，將本研
究所採取的汽車油漆片元素含量之分析方法，實際應用於肇事案件中的汽車油漆磨混
(Smear) 樣品，嘗試評估其是否具有鑑別的可行性，並且為利於進行汽車油漆磨混樣品
的顯微紅外線光譜(Micro/FTIR)與電子顯微鏡／X-射線能譜之系統性分析，則在案例中
探討可兼顧兩者需要的汽車油漆磨混樣品之前處理方式。
Scanning electron microscopy/energy dispersive X-ray spectrometry
(SEM/EDX) and Micro/FTIR are two commonly used methods for the
identification of automotive paints. However to deal with real caseworks, it
was anticipated with such a Micro/FTIR system, with an emphasis on the
analysis of organic resins, may still inevitably encounter some
difficulties. To further enhance the evidential value of trace automotive
paints. SEM/EDX directed toward the analysis of inorganic elements is
recommended whenever need. In this study we especially take case of
deviations from comparison between standard and weathered samples for the
application of library searching. Five different color (green, blue, red,
white, yellow) paints were collected from four motor companies (Civic,
Ford, Toyota, Yuelong). All standard samples were artificially weathered in
the Xenon Arc Lamp Type Apparatus (JIS K 5400). However, after 600 hours on
accelerated weathering test, we find no significant difference in the
quantity of element on such automotive paint chips with inorganic pigments.
The results show inorganic pigments of automotive paint chips are more
applicable to engage the test of significant variability. As for the
variation of the gloss, every automotive paint chip with a clear layer
decays gradually by the increase of accelerated weathering time. At the same
time, the colors of different automotive paint chips also have their
variations. The method we adopted on analysis of the element quantities of
automotive point chips can be applied to evaluating the feasibility of
smear sample in actual cases. To engage the process of the systematic
analysis of Micro/FTIR and SEM/EDX, the pretreatment method in the actual
case that could give consideration to the desires of both Micro/FTIR and
SEM/EDX was discussed.
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