糯米是亞洲的主要農經產物之一,但其應用一直侷限於食品工業產品上,在造紙工業上糯 米之應用,則未有所聞。就糯米之化學組成而觀,其幾乎全為凝腦澱粉,因此糯米應可作為紙張塗 佈用之接著劑。本論文研究的實驗結果顯示,糯米確可作為紙張塗佈用接著劑,且能提供與現今紙 張塗佈常用的接著劑──玉米澱粉及大豆蛋白相近的塗佈性質。另外,若糯米經過鹼性或酸性處理 後,更可提高塗佈紙的光學和強度性質。經鹼性處理過之糯米,可提高塗佈紙張之拔蠟強度及光澤 度;而經微酸處理過之糯米,則可提昇塗佈紙之白度及不透明度。本研究共探討三種糯米:長糯米、 短糯米,和黑糯米。在未經處理前,實驗結果顯示短糯米最適合用做紙張塗佈用接著劑。而經過鹼 性處理後,則以長糯米較為優良,經酸性處理後之糯米,實驗之結論為,酸性處理之糯米應在極度 稀釋的反應條件下進行,以求塗佈紙張應有之拔蠟強度。
Sticky rice is one of the major agricultural products in Asia. Its application, however, have been limited only to the food products, and no literature reports could be found about its application to paper products. In view of its chemical composition containing almost all amylopectin, sticky rice starch should be applicable to the paper coatings. This report presents the research results on the applicability of sticky rice as the paper coating binder. Experimental results indicate that sticky rice is applicable as coating binder, since when applied in the same formulation, sticky rice provides similar paper coating properties as do corn starch and soy protein the commonly used coating binders. The coating properties can even be enhanced using sticky rice after alkaline or acid treatment. Sodium hydroxide treatment results in improved picking resistance and gloss. And light hydrogen chloride treatment provides greater brightness and opacity. Three different types of waxy rice were studied, namely, long, short, and black sticky rice. Among them, short sticky rice performs the best as a coating binder. However after the alkaline treatment, long sticky rice yields better coating properties than either short or black sticky rice. Finally, the experimental results suggest that a critically diluted concentration should be practiced with the acid treatment in order to maintain the picking resistance.