TREATING AGENT FOR DECOMPOSING UNSTABLE TERMINAL GROUP, STABILIZED POLYACETAL RESIN PRODUCED WITH THE SAME, PRODUCTION PROCESS, COMPOSITION, AND MOLDED OBJECT

摘要

A process for producing a stabilized polyacetal resin which comprises heating a polyacetal resin having unstable terminal groups in the presence of a treating agent for unstable-terminal-group decomposition selected from the following groups (I), (II), and (III) to thereby diminish the unstable terminal groups. Treating agents for unstable-terminal-group decomposition in group (I) Group (I): quaternary ammonium salts of acid cyclic amide compounds Treating agents for unstable-terminal-group decomposition in group (II) Group (II): quaternary ammonium salts of polycarboxylic acids having four or more carboxy groups per molecule and/or quaternary ammonium salts of aminocarboxylic acids having one or more carboxy groups per molecule Treating agents for unstable-terminal-group decomposition in group (III) Group (III): quaternary ammonium salts in which the counter anions are ones derived from at least one compound selected from the group consisting of the following (i) to (v): (i) carbonic acid monoesters and/or metal hydrogen carbonates; (ii) acid enol compounds; (iii) phenolic compounds and alcoholic compounds; (iv) acid azole compounds; and (v) at least one noncarboxylic acid compound selected from the group consisting of organosulfur compounds, organophosphorus compounds, and organoboron compounds.