Abstract: The amorphous inorganic anion exchanger of the present invention is represented by Formula (1) and has an average primary particle size observed with an electron microscope of at least 1 nm but no greater than 500 nm and an NO3 content of no greater than 1 wt % of the whole: BiO(OH)??Formula (1).

Abstract: The object is to provide an amorphous inorganic anion exchanger having excellent anion exchangeability and suppressed corrosivity toward metals and to provide a production process that can produce an amorphous bismuth compound having excellent anion exchangeability and suppressed corrosivity toward metals. The amorphous inorganic anion exchanger of the present invention is represented by Formula (1) and has an average primary particle size observed with an electron microscope of at least 1 nm but no greater than 500 nm and an NO3 content of no greater than 1 wt % of the whole. The process for producing an amorphous bismuth compound of the present invention includes a precipitate formation step of forming a precipitate by subjecting an acidic aqueous solution containing trivalent Bi ions to a temperature in the range of higher than 0° C. but less than 20° C.

Abstract: An epoxy resin composition for use in sealing semiconductors, having enhanced moisture resistance reliability is disclosed, which comprises an epoxy resin and an oxyacid bismuth oxyhydroxide represented by the following formula (1):Bi.sub.x O.sub.y (OH).sub.p (Y.sup.-a).sub.q (NO.sub.3).sub.r.nH.sub.2 O (1)wherein Y.sup.-a represents a residue of an oxyacid other than nitrate; a represents the ionic valence, absolute value, of the residue of the oxyacid; and x, y, p, q, r and n each represents a value satisfying the following:1.ltoreq.x 1.ltoreq.y O.ltoreq.n0.08 x.ltoreq.p.ltoreq.0.92 x0.02 x.ltoreq.aq.ltoreq.0.92 x0.ltoreq.r.ltoreq.0.