To provide a stabilizer compsn. which is excellent in stabilizing org. materials, such as synthetic resins, rubbers, and coating materials by using a combination of a specific phosphite compd. with a phenolic stabilizer or a hindered amine stabilizer.
This compsn. comprises a phosphite compd. of the formula (wherein R1 to R6 are each H or 1-8C alkyl provided they other than R3 and R6 may each be 5-8C cycloalkyl, 7-12C aryl or the like; X1 is an alcohol residue; X2 is a single bond or 1-8C alkylene; and Y is hydroxyl, 1-8C alkoxy, or the like) and a phenolic or hindered amine stabilizer in a wt. ratio of (10:1)-(1:10). Pref., in the formula, R1 and R2 are each t-butyl; one of R4 and R5 is t-butyl and the other is methyl or t-butyl ; and R3 and R6 are both H or methyl. The phosphite compd. is prepd. by reacting a phenol which constitutes the left side of the formula, a phosphorus trihalide, and an alcohol which constitutes the right side of the formula by using a dehydrohalogenating agent. The stabilizer compsn. effectively stabilizes org. materials against degradation by heat or oxidation.
FUKUDA KANAKO
SASAKI MANJI
