ORGANIC POLYMER MATERIAL CONTAINING XANTHENE-2,7-DIOL COMPOUND

PROBLEM TO BE SOLVED: To prevent an organic polymer material from the deterioration of its quality such as the change of a physical property even when it experiences thermal history over time during being processed or used by compounding one or more organic compounds having a specific structure with an organic polymer. SOLUTION: A compound combined with an organic polymer is represented by the formula, wherein each of R1, R2 and R3 is hydrogen atom, a 1-4C straight- or branched-chain alkyl group and these may be the same or different to each other. R4 is hydrogen atom, a 1-18C linear, branched or cyclic alkyl group or a (un)substituted aryl group. Preferably, an organic polymer material further comprises a phenolic antioxidant and/or phosphorous antioxidant together with a compound of the formula. The amount of the compound of the formula is preferably 1-20 wt.% relative to the total amount of the polymer material and said antioxidant.