Carbonates and urethanes of 2,2'-alkylene or -cycloalkylene-bis-4,6-disubstituted phenols as stabilizers for organic materials

A compound of the formula, ##STR29## wherein each R.sub.1, independently, is (C.sub.1-8)alkyl, (C.sub.5-9)cycloalkyl or monomethyl(C.sub.5-9)cycloalkyl, each

• R.sub.2, independently, is (C.sub.1-8)alkyl, (C.sub.5-9)cycloalkyl, halo, phenyl or mono (C.sub.1-9)alkylphenyl, and either each
• R.sub.3 is hydrogen, (C.sub.1-18)alkyl, (C.sub.5-9)-cycloalkyl or phenyl, and each
• R.sub.4 is hydrogen or (C.sub.1-18)alkyl, or each ##STR30## unit forms a (C.sub.5-7) saturated aliphatic hydrocarbon ring, with the proviso that both groups of the formula ##STR31## are identical.