| abstract |
PURPOSE: To improve the water-resistance and coloring flexibility of the subject article, by using a filler produced by the surface-treatment of glass powder containing SiO 2 , Al 2 O 3 , CaO, MgO, B 2 O 3 , Na 2 O, As 2 O 3 , Sb 2 O 3 and Fe 2 O 3 at respective specific ranges and containing a specific amount of fluorine. n CONSTITUTION: Water-granulated glass containing 0.2-1.6pts.wt. of fluorine based on 100pts.wt. of a composition containing 22-26wt.% CaO+MgO, 51-55wt.% SiO 2 , 12-15wt.% Al 2 O 3 , 20-25wt.% CaO, 0-4wt.% MgO, 4.5-6.5wt.% B 2 O 3 , 1.5-4wt.% Na 2 O, 0-0.2wt.% As 2 O 3 , 0-0.2wt.% Sb 2 O 3 and ≤0.1wt.% Fe 2 O 3 is prepared beforehand. The prepared glass is added with a silane coupling agent or an organosiloxane (e.g., γ-methacryloxypropyltri methoxysilane) and crushed in wet state and, at the same time, surface-treated. The product is dehydrated and dried to obtain a filler for a thermosetting resin. n COPYRIGHT: (C)1989,JPO&Japio |