本研究以CO2/O2氣體感測器及圖像分析方法，探討馬藍植物(Strobilanthes cusia)進行藍染過程的變化。本研究取自陽明山上的馬藍葉進行實驗。結果發現，測量製藍過程中CO2和O2的濃度，可以用來評估靛藍產量的多寡；溫泉水的效果比其他水質更好且水溫為30度時，產量及色澤最佳，高於40度則效果遞減；製藍反應會先產生CO2後才開始消耗O2；馬藍葉摘下後會隨著放置時間增加而尿藍素會逐漸流失；新葉製藍產量比老葉還高，葉的產量比莖高。
本研究使用連二亞硫酸鈉(Na2S2O4)當作還原劑，使用HBV圖像分析法比較pH 3-13範圍，證明在任何酸鹼度都可用來染色，在pH 13時染色效果最好，pH 11以下染色能力大幅下降；藍泥與連二亞硫酸鈉的最佳重量比為1:14，使染色效果最接近於理論藍色值；藍染時最佳溫度約30°C。使用RGB圖像分析法建立建藍染液的三個階段，為 0-25分鐘的建藍初始期，R值上升緩慢染色效果差；在25-70分鐘的建藍成長期，R值上升速度快染色能力提升，在70分時有最佳的染色能力；最後70-180分鐘的建藍衰退期，R值隨時間下降染色能力下降。藉由本研究的分析方法找出最佳反應條件。

In this study, we used CO2/O2 gas sensor and applied image analysis for exploring that Strobilanthes cusia plant varied in the indigo dyeing process. We picked the leaves from Strobilanthes cusia growing in Yangmingshan for our experiments. There were five results coming out in the end. First, it was found that measuring the density of CO2 and O2 generated in the process of indigo production can adopt to assess the production of indigo. Second, the effect of hot spring is better than other type of water and the best production and color are yielded under the condition at the water temperature of 30 degrees; however, the effect of hot spring diminishes under the condition at the water temperature higher than 40 degrees. Third, the reaction of producing indigo will first generate CO2 before consuming O2. Fourth, after leaves are picked from Strobilanthes cusia, indican will gradually lose along with the increase of storage time. Fifth, the production of indigo yielded from young leaves is higher than that yielded from old leaves, and the production of indigo yielded from leaves is higher than that yielded from stems.
In this study, sodium dithionite (Na2S2O4) was used as the reductant, and HBV image analysis was applied to compare the range for dyeing from pH 3 to pH 13. There are three findings proven after our analysis. First, we proved that dyeing can be conducted at any pH. The best dyeing effect is reached under the condition of pH 13, and the dyeing effect dramatically decline when pH value is below 11. Second, the best ratio of indigo to sodium dithionite is 1:14, which makes the dyeing effect closest to the theoretical value. Third, the best temperature for dyeing is about 30°C. Additionally, we employ the RGB image analysis to establish three stages of building solution for indigo dyeing. In the initial period during 0-25th minutes, the R value rises slowly and the dyeing effect is poor. In the growth period during 25th-70th minutes, the R value rises quickly and the dyeing effect is increase, and the dyeing effect is optimal at 70th minutes; in the decline period during the last 70th-180th minutes, the R value decreases along with time and the dyeing effect decreases as well. In conclusion, we found the best reaction conditions for dyeing through analytical methods in this study.

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