最近,杜邦公司研究了一种缩短薄壳制作时间的新方法。这种方法称为Calal法。其原理是:利用二种不同类型的粘结剂在交替涂刷的过程中所发生的反应来制作薄壳。这两种粘结剂名为CalalP和CalalM。前者系一种呈弱酸性的氧化铝一二氧化硅水溶液;后者系一种略呈碱性的二氧化硅水溶液。将这两种粘结剂分别与普通的 Recently, DuPont has studied a new method of shortening the production time of the shell. This method is called Calal method. The principle is: the use of two different types of adhesives in the process of alternating brushing reaction to produce thin shell. The two binders are named CalalP and CalalM. The former is a weakly acidic aqueous solution of alumina-silica; the latter is a slightly alkaline aqueous solution of silica. Separate these two adhesives with normal ones